diff options
Diffstat (limited to 'drivers/cxl/core')
| -rw-r--r-- | drivers/cxl/core/Makefile | 13 | ||||
| -rw-r--r-- | drivers/cxl/core/core.h | 63 | ||||
| -rw-r--r-- | drivers/cxl/core/hdm.c | 865 | ||||
| -rw-r--r-- | drivers/cxl/core/mbox.c | 862 | ||||
| -rw-r--r-- | drivers/cxl/core/memdev.c | 386 | ||||
| -rw-r--r-- | drivers/cxl/core/pci.c | 702 | ||||
| -rw-r--r-- | drivers/cxl/core/pmem.c | 285 | ||||
| -rw-r--r-- | drivers/cxl/core/port.c | 1894 | ||||
| -rw-r--r-- | drivers/cxl/core/region.c | 2006 | ||||
| -rw-r--r-- | drivers/cxl/core/regs.c | 304 | ||||
| -rw-r--r-- | drivers/cxl/core/suspend.c | 24 |
11 files changed, 7404 insertions, 0 deletions
diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile new file mode 100644 index 000000000..79c7257f4 --- /dev/null +++ b/drivers/cxl/core/Makefile @@ -0,0 +1,13 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_CXL_BUS) += cxl_core.o +obj-$(CONFIG_CXL_SUSPEND) += suspend.o + +ccflags-y += -I$(srctree)/drivers/cxl +cxl_core-y := port.o +cxl_core-y += pmem.o +cxl_core-y += regs.o +cxl_core-y += memdev.o +cxl_core-y += mbox.o +cxl_core-y += pci.o +cxl_core-y += hdm.o +cxl_core-$(CONFIG_CXL_REGION) += region.o diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h new file mode 100644 index 000000000..cbee2340f --- /dev/null +++ b/drivers/cxl/core/core.h @@ -0,0 +1,63 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* Copyright(c) 2020 Intel Corporation. */ + +#ifndef __CXL_CORE_H__ +#define __CXL_CORE_H__ + +extern const struct device_type cxl_nvdimm_bridge_type; +extern const struct device_type cxl_nvdimm_type; + +extern struct attribute_group cxl_base_attribute_group; + +#ifdef CONFIG_CXL_REGION +extern struct device_attribute dev_attr_create_pmem_region; +extern struct device_attribute dev_attr_delete_region; +extern struct device_attribute dev_attr_region; +extern const struct device_type cxl_pmem_region_type; +extern const struct device_type cxl_region_type; +void cxl_decoder_kill_region(struct cxl_endpoint_decoder *cxled); +#define CXL_REGION_ATTR(x) (&dev_attr_##x.attr) +#define CXL_REGION_TYPE(x) (&cxl_region_type) +#define SET_CXL_REGION_ATTR(x) (&dev_attr_##x.attr), +#define CXL_PMEM_REGION_TYPE(x) (&cxl_pmem_region_type) +int cxl_region_init(void); +void cxl_region_exit(void); +#else +static inline void cxl_decoder_kill_region(struct cxl_endpoint_decoder *cxled) +{ +} +static inline int cxl_region_init(void) +{ + return 0; +} +static inline void cxl_region_exit(void) +{ +} +#define CXL_REGION_ATTR(x) NULL +#define CXL_REGION_TYPE(x) NULL +#define SET_CXL_REGION_ATTR(x) +#define CXL_PMEM_REGION_TYPE(x) NULL +#endif + +struct cxl_send_command; +struct cxl_mem_query_commands; +int cxl_query_cmd(struct cxl_memdev *cxlmd, + struct cxl_mem_query_commands __user *q); +int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s); +void __iomem *devm_cxl_iomap_block(struct device *dev, resource_size_t addr, + resource_size_t length); + +struct dentry *cxl_debugfs_create_dir(const char *dir); +int cxl_dpa_set_mode(struct cxl_endpoint_decoder *cxled, + enum cxl_decoder_mode mode); +int cxl_dpa_alloc(struct cxl_endpoint_decoder *cxled, unsigned long long size); +int cxl_dpa_free(struct cxl_endpoint_decoder *cxled); +resource_size_t cxl_dpa_size(struct cxl_endpoint_decoder *cxled); +resource_size_t cxl_dpa_resource_start(struct cxl_endpoint_decoder *cxled); +extern struct rw_semaphore cxl_dpa_rwsem; + +int cxl_memdev_init(void); +void cxl_memdev_exit(void); +void cxl_mbox_init(void); + +#endif /* __CXL_CORE_H__ */ diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c new file mode 100644 index 000000000..8c1db4e1b --- /dev/null +++ b/drivers/cxl/core/hdm.c @@ -0,0 +1,865 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2022 Intel Corporation. All rights reserved. */ +#include <linux/io-64-nonatomic-hi-lo.h> +#include <linux/seq_file.h> +#include <linux/device.h> +#include <linux/delay.h> + +#include "cxlmem.h" +#include "core.h" + +/** + * DOC: cxl core hdm + * + * Compute Express Link Host Managed Device Memory, starting with the + * CXL 2.0 specification, is managed by an array of HDM Decoder register + * instances per CXL port and per CXL endpoint. Define common helpers + * for enumerating these registers and capabilities. + */ + +DECLARE_RWSEM(cxl_dpa_rwsem); + +static int add_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, + int *target_map) +{ + int rc; + + rc = cxl_decoder_add_locked(cxld, target_map); + if (rc) { + put_device(&cxld->dev); + dev_err(&port->dev, "Failed to add decoder\n"); + return rc; + } + + rc = cxl_decoder_autoremove(&port->dev, cxld); + if (rc) + return rc; + + dev_dbg(&cxld->dev, "Added to port %s\n", dev_name(&port->dev)); + + return 0; +} + +/* + * Per the CXL specification (8.2.5.12 CXL HDM Decoder Capability Structure) + * single ported host-bridges need not publish a decoder capability when a + * passthrough decode can be assumed, i.e. all transactions that the uport sees + * are claimed and passed to the single dport. Disable the range until the first + * CXL region is enumerated / activated. + */ +int devm_cxl_add_passthrough_decoder(struct cxl_port *port) +{ + struct cxl_switch_decoder *cxlsd; + struct cxl_dport *dport = NULL; + int single_port_map[1]; + unsigned long index; + + cxlsd = cxl_switch_decoder_alloc(port, 1); + if (IS_ERR(cxlsd)) + return PTR_ERR(cxlsd); + + device_lock_assert(&port->dev); + + xa_for_each(&port->dports, index, dport) + break; + single_port_map[0] = dport->port_id; + + return add_hdm_decoder(port, &cxlsd->cxld, single_port_map); +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_add_passthrough_decoder, CXL); + +static void parse_hdm_decoder_caps(struct cxl_hdm *cxlhdm) +{ + u32 hdm_cap; + + hdm_cap = readl(cxlhdm->regs.hdm_decoder + CXL_HDM_DECODER_CAP_OFFSET); + cxlhdm->decoder_count = cxl_hdm_decoder_count(hdm_cap); + cxlhdm->target_count = + FIELD_GET(CXL_HDM_DECODER_TARGET_COUNT_MASK, hdm_cap); + if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_11_8, hdm_cap)) + cxlhdm->interleave_mask |= GENMASK(11, 8); + if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_14_12, hdm_cap)) + cxlhdm->interleave_mask |= GENMASK(14, 12); +} + +static void __iomem *map_hdm_decoder_regs(struct cxl_port *port, + void __iomem *crb) +{ + struct cxl_component_reg_map map; + + cxl_probe_component_regs(&port->dev, crb, &map); + if (!map.hdm_decoder.valid) { + dev_err(&port->dev, "HDM decoder registers invalid\n"); + return IOMEM_ERR_PTR(-ENXIO); + } + + return crb + map.hdm_decoder.offset; +} + +/** + * devm_cxl_setup_hdm - map HDM decoder component registers + * @port: cxl_port to map + */ +struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port) +{ + struct device *dev = &port->dev; + void __iomem *crb, *hdm; + struct cxl_hdm *cxlhdm; + + cxlhdm = devm_kzalloc(dev, sizeof(*cxlhdm), GFP_KERNEL); + if (!cxlhdm) + return ERR_PTR(-ENOMEM); + + cxlhdm->port = port; + crb = devm_cxl_iomap_block(dev, port->component_reg_phys, + CXL_COMPONENT_REG_BLOCK_SIZE); + if (!crb) { + dev_err(dev, "No component registers mapped\n"); + return ERR_PTR(-ENXIO); + } + + hdm = map_hdm_decoder_regs(port, crb); + if (IS_ERR(hdm)) + return ERR_CAST(hdm); + cxlhdm->regs.hdm_decoder = hdm; + + parse_hdm_decoder_caps(cxlhdm); + if (cxlhdm->decoder_count == 0) { + dev_err(dev, "Spec violation. Caps invalid\n"); + return ERR_PTR(-ENXIO); + } + + dev_set_drvdata(dev, cxlhdm); + + return cxlhdm; +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_setup_hdm, CXL); + +static void __cxl_dpa_debug(struct seq_file *file, struct resource *r, int depth) +{ + unsigned long long start = r->start, end = r->end; + + seq_printf(file, "%*s%08llx-%08llx : %s\n", depth * 2, "", start, end, + r->name); +} + +void cxl_dpa_debug(struct seq_file *file, struct cxl_dev_state *cxlds) +{ + struct resource *p1, *p2; + + down_read(&cxl_dpa_rwsem); + for (p1 = cxlds->dpa_res.child; p1; p1 = p1->sibling) { + __cxl_dpa_debug(file, p1, 0); + for (p2 = p1->child; p2; p2 = p2->sibling) + __cxl_dpa_debug(file, p2, 1); + } + up_read(&cxl_dpa_rwsem); +} +EXPORT_SYMBOL_NS_GPL(cxl_dpa_debug, CXL); + +/* + * Must be called in a context that synchronizes against this decoder's + * port ->remove() callback (like an endpoint decoder sysfs attribute) + */ +static void __cxl_dpa_release(struct cxl_endpoint_decoder *cxled) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_port *port = cxled_to_port(cxled); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct resource *res = cxled->dpa_res; + resource_size_t skip_start; + + lockdep_assert_held_write(&cxl_dpa_rwsem); + + /* save @skip_start, before @res is released */ + skip_start = res->start - cxled->skip; + __release_region(&cxlds->dpa_res, res->start, resource_size(res)); + if (cxled->skip) + __release_region(&cxlds->dpa_res, skip_start, cxled->skip); + cxled->skip = 0; + cxled->dpa_res = NULL; + put_device(&cxled->cxld.dev); + port->hdm_end--; +} + +static void cxl_dpa_release(void *cxled) +{ + down_write(&cxl_dpa_rwsem); + __cxl_dpa_release(cxled); + up_write(&cxl_dpa_rwsem); +} + +/* + * Must be called from context that will not race port device + * unregistration, like decoder sysfs attribute methods + */ +static void devm_cxl_dpa_release(struct cxl_endpoint_decoder *cxled) +{ + struct cxl_port *port = cxled_to_port(cxled); + + lockdep_assert_held_write(&cxl_dpa_rwsem); + devm_remove_action(&port->dev, cxl_dpa_release, cxled); + __cxl_dpa_release(cxled); +} + +static int __cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled, + resource_size_t base, resource_size_t len, + resource_size_t skipped) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_port *port = cxled_to_port(cxled); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct device *dev = &port->dev; + struct resource *res; + + lockdep_assert_held_write(&cxl_dpa_rwsem); + + if (!len) { + dev_warn(dev, "decoder%d.%d: empty reservation attempted\n", + port->id, cxled->cxld.id); + return -EINVAL; + } + + if (cxled->dpa_res) { + dev_dbg(dev, "decoder%d.%d: existing allocation %pr assigned\n", + port->id, cxled->cxld.id, cxled->dpa_res); + return -EBUSY; + } + + if (port->hdm_end + 1 != cxled->cxld.id) { + /* + * Assumes alloc and commit order is always in hardware instance + * order per expectations from 8.2.5.12.20 Committing Decoder + * Programming that enforce decoder[m] committed before + * decoder[m+1] commit start. + */ + dev_dbg(dev, "decoder%d.%d: expected decoder%d.%d\n", port->id, + cxled->cxld.id, port->id, port->hdm_end + 1); + return -EBUSY; + } + + if (skipped) { + res = __request_region(&cxlds->dpa_res, base - skipped, skipped, + dev_name(&cxled->cxld.dev), 0); + if (!res) { + dev_dbg(dev, + "decoder%d.%d: failed to reserve skipped space\n", + port->id, cxled->cxld.id); + return -EBUSY; + } + } + res = __request_region(&cxlds->dpa_res, base, len, + dev_name(&cxled->cxld.dev), 0); + if (!res) { + dev_dbg(dev, "decoder%d.%d: failed to reserve allocation\n", + port->id, cxled->cxld.id); + if (skipped) + __release_region(&cxlds->dpa_res, base - skipped, + skipped); + return -EBUSY; + } + cxled->dpa_res = res; + cxled->skip = skipped; + + if (resource_contains(&cxlds->pmem_res, res)) + cxled->mode = CXL_DECODER_PMEM; + else if (resource_contains(&cxlds->ram_res, res)) + cxled->mode = CXL_DECODER_RAM; + else { + dev_dbg(dev, "decoder%d.%d: %pr mixed\n", port->id, + cxled->cxld.id, cxled->dpa_res); + cxled->mode = CXL_DECODER_MIXED; + } + + port->hdm_end++; + get_device(&cxled->cxld.dev); + return 0; +} + +int devm_cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled, + resource_size_t base, resource_size_t len, + resource_size_t skipped) +{ + struct cxl_port *port = cxled_to_port(cxled); + int rc; + + down_write(&cxl_dpa_rwsem); + rc = __cxl_dpa_reserve(cxled, base, len, skipped); + up_write(&cxl_dpa_rwsem); + + if (rc) + return rc; + + return devm_add_action_or_reset(&port->dev, cxl_dpa_release, cxled); +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_dpa_reserve, CXL); + +resource_size_t cxl_dpa_size(struct cxl_endpoint_decoder *cxled) +{ + resource_size_t size = 0; + + down_read(&cxl_dpa_rwsem); + if (cxled->dpa_res) + size = resource_size(cxled->dpa_res); + up_read(&cxl_dpa_rwsem); + + return size; +} + +resource_size_t cxl_dpa_resource_start(struct cxl_endpoint_decoder *cxled) +{ + resource_size_t base = -1; + + down_read(&cxl_dpa_rwsem); + if (cxled->dpa_res) + base = cxled->dpa_res->start; + up_read(&cxl_dpa_rwsem); + + return base; +} + +int cxl_dpa_free(struct cxl_endpoint_decoder *cxled) +{ + struct cxl_port *port = cxled_to_port(cxled); + struct device *dev = &cxled->cxld.dev; + int rc; + + down_write(&cxl_dpa_rwsem); + if (!cxled->dpa_res) { + rc = 0; + goto out; + } + if (cxled->cxld.region) { + dev_dbg(dev, "decoder assigned to: %s\n", + dev_name(&cxled->cxld.region->dev)); + rc = -EBUSY; + goto out; + } + if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) { + dev_dbg(dev, "decoder enabled\n"); + rc = -EBUSY; + goto out; + } + if (cxled->cxld.id != port->hdm_end) { + dev_dbg(dev, "expected decoder%d.%d\n", port->id, + port->hdm_end); + rc = -EBUSY; + goto out; + } + devm_cxl_dpa_release(cxled); + rc = 0; +out: + up_write(&cxl_dpa_rwsem); + return rc; +} + +int cxl_dpa_set_mode(struct cxl_endpoint_decoder *cxled, + enum cxl_decoder_mode mode) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct device *dev = &cxled->cxld.dev; + int rc; + + switch (mode) { + case CXL_DECODER_RAM: + case CXL_DECODER_PMEM: + break; + default: + dev_dbg(dev, "unsupported mode: %d\n", mode); + return -EINVAL; + } + + down_write(&cxl_dpa_rwsem); + if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) { + rc = -EBUSY; + goto out; + } + + /* + * Only allow modes that are supported by the current partition + * configuration + */ + if (mode == CXL_DECODER_PMEM && !resource_size(&cxlds->pmem_res)) { + dev_dbg(dev, "no available pmem capacity\n"); + rc = -ENXIO; + goto out; + } + if (mode == CXL_DECODER_RAM && !resource_size(&cxlds->ram_res)) { + dev_dbg(dev, "no available ram capacity\n"); + rc = -ENXIO; + goto out; + } + + cxled->mode = mode; + rc = 0; +out: + up_write(&cxl_dpa_rwsem); + + return rc; +} + +int cxl_dpa_alloc(struct cxl_endpoint_decoder *cxled, unsigned long long size) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + resource_size_t free_ram_start, free_pmem_start; + struct cxl_port *port = cxled_to_port(cxled); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct device *dev = &cxled->cxld.dev; + resource_size_t start, avail, skip; + struct resource *p, *last; + int rc; + + down_write(&cxl_dpa_rwsem); + if (cxled->cxld.region) { + dev_dbg(dev, "decoder attached to %s\n", + dev_name(&cxled->cxld.region->dev)); + rc = -EBUSY; + goto out; + } + + if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) { + dev_dbg(dev, "decoder enabled\n"); + rc = -EBUSY; + goto out; + } + + for (p = cxlds->ram_res.child, last = NULL; p; p = p->sibling) + last = p; + if (last) + free_ram_start = last->end + 1; + else + free_ram_start = cxlds->ram_res.start; + + for (p = cxlds->pmem_res.child, last = NULL; p; p = p->sibling) + last = p; + if (last) + free_pmem_start = last->end + 1; + else + free_pmem_start = cxlds->pmem_res.start; + + if (cxled->mode == CXL_DECODER_RAM) { + start = free_ram_start; + avail = cxlds->ram_res.end - start + 1; + skip = 0; + } else if (cxled->mode == CXL_DECODER_PMEM) { + resource_size_t skip_start, skip_end; + + start = free_pmem_start; + avail = cxlds->pmem_res.end - start + 1; + skip_start = free_ram_start; + + /* + * If some pmem is already allocated, then that allocation + * already handled the skip. + */ + if (cxlds->pmem_res.child && + skip_start == cxlds->pmem_res.child->start) + skip_end = skip_start - 1; + else + skip_end = start - 1; + skip = skip_end - skip_start + 1; + } else { + dev_dbg(dev, "mode not set\n"); + rc = -EINVAL; + goto out; + } + + if (size > avail) { + dev_dbg(dev, "%pa exceeds available %s capacity: %pa\n", &size, + cxled->mode == CXL_DECODER_RAM ? "ram" : "pmem", + &avail); + rc = -ENOSPC; + goto out; + } + + rc = __cxl_dpa_reserve(cxled, start, size, skip); +out: + up_write(&cxl_dpa_rwsem); + + if (rc) + return rc; + + return devm_add_action_or_reset(&port->dev, cxl_dpa_release, cxled); +} + +static void cxld_set_interleave(struct cxl_decoder *cxld, u32 *ctrl) +{ + u16 eig; + u8 eiw; + + /* + * Input validation ensures these warns never fire, but otherwise + * suppress unititalized variable usage warnings. + */ + if (WARN_ONCE(ways_to_cxl(cxld->interleave_ways, &eiw), + "invalid interleave_ways: %d\n", cxld->interleave_ways)) + return; + if (WARN_ONCE(granularity_to_cxl(cxld->interleave_granularity, &eig), + "invalid interleave_granularity: %d\n", + cxld->interleave_granularity)) + return; + + u32p_replace_bits(ctrl, eig, CXL_HDM_DECODER0_CTRL_IG_MASK); + u32p_replace_bits(ctrl, eiw, CXL_HDM_DECODER0_CTRL_IW_MASK); + *ctrl |= CXL_HDM_DECODER0_CTRL_COMMIT; +} + +static void cxld_set_type(struct cxl_decoder *cxld, u32 *ctrl) +{ + u32p_replace_bits(ctrl, !!(cxld->target_type == 3), + CXL_HDM_DECODER0_CTRL_TYPE); +} + +static int cxlsd_set_targets(struct cxl_switch_decoder *cxlsd, u64 *tgt) +{ + struct cxl_dport **t = &cxlsd->target[0]; + int ways = cxlsd->cxld.interleave_ways; + + if (dev_WARN_ONCE(&cxlsd->cxld.dev, + ways > 8 || ways > cxlsd->nr_targets, + "ways: %d overflows targets: %d\n", ways, + cxlsd->nr_targets)) + return -ENXIO; + + *tgt = FIELD_PREP(GENMASK(7, 0), t[0]->port_id); + if (ways > 1) + *tgt |= FIELD_PREP(GENMASK(15, 8), t[1]->port_id); + if (ways > 2) + *tgt |= FIELD_PREP(GENMASK(23, 16), t[2]->port_id); + if (ways > 3) + *tgt |= FIELD_PREP(GENMASK(31, 24), t[3]->port_id); + if (ways > 4) + *tgt |= FIELD_PREP(GENMASK_ULL(39, 32), t[4]->port_id); + if (ways > 5) + *tgt |= FIELD_PREP(GENMASK_ULL(47, 40), t[5]->port_id); + if (ways > 6) + *tgt |= FIELD_PREP(GENMASK_ULL(55, 48), t[6]->port_id); + if (ways > 7) + *tgt |= FIELD_PREP(GENMASK_ULL(63, 56), t[7]->port_id); + + return 0; +} + +/* + * Per CXL 2.0 8.2.5.12.20 Committing Decoder Programming, hardware must set + * committed or error within 10ms, but just be generous with 20ms to account for + * clock skew and other marginal behavior + */ +#define COMMIT_TIMEOUT_MS 20 +static int cxld_await_commit(void __iomem *hdm, int id) +{ + u32 ctrl; + int i; + + for (i = 0; i < COMMIT_TIMEOUT_MS; i++) { + ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); + if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMIT_ERROR, ctrl)) { + ctrl &= ~CXL_HDM_DECODER0_CTRL_COMMIT; + writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); + return -EIO; + } + if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl)) + return 0; + fsleep(1000); + } + + return -ETIMEDOUT; +} + +static int cxl_decoder_commit(struct cxl_decoder *cxld) +{ + struct cxl_port *port = to_cxl_port(cxld->dev.parent); + struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev); + void __iomem *hdm = cxlhdm->regs.hdm_decoder; + int id = cxld->id, rc; + u64 base, size; + u32 ctrl; + + if (cxld->flags & CXL_DECODER_F_ENABLE) + return 0; + + if (port->commit_end + 1 != id) { + dev_dbg(&port->dev, + "%s: out of order commit, expected decoder%d.%d\n", + dev_name(&cxld->dev), port->id, port->commit_end + 1); + return -EBUSY; + } + + down_read(&cxl_dpa_rwsem); + /* common decoder settings */ + ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); + cxld_set_interleave(cxld, &ctrl); + cxld_set_type(cxld, &ctrl); + base = cxld->hpa_range.start; + size = range_len(&cxld->hpa_range); + + writel(upper_32_bits(base), hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(id)); + writel(lower_32_bits(base), hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(id)); + writel(upper_32_bits(size), hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(id)); + writel(lower_32_bits(size), hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(id)); + + if (is_switch_decoder(&cxld->dev)) { + struct cxl_switch_decoder *cxlsd = + to_cxl_switch_decoder(&cxld->dev); + void __iomem *tl_hi = hdm + CXL_HDM_DECODER0_TL_HIGH(id); + void __iomem *tl_lo = hdm + CXL_HDM_DECODER0_TL_LOW(id); + u64 targets; + + rc = cxlsd_set_targets(cxlsd, &targets); + if (rc) { + dev_dbg(&port->dev, "%s: target configuration error\n", + dev_name(&cxld->dev)); + goto err; + } + + writel(upper_32_bits(targets), tl_hi); + writel(lower_32_bits(targets), tl_lo); + } else { + struct cxl_endpoint_decoder *cxled = + to_cxl_endpoint_decoder(&cxld->dev); + void __iomem *sk_hi = hdm + CXL_HDM_DECODER0_SKIP_HIGH(id); + void __iomem *sk_lo = hdm + CXL_HDM_DECODER0_SKIP_LOW(id); + + writel(upper_32_bits(cxled->skip), sk_hi); + writel(lower_32_bits(cxled->skip), sk_lo); + } + + writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); + up_read(&cxl_dpa_rwsem); + + port->commit_end++; + rc = cxld_await_commit(hdm, cxld->id); +err: + if (rc) { + dev_dbg(&port->dev, "%s: error %d committing decoder\n", + dev_name(&cxld->dev), rc); + cxld->reset(cxld); + return rc; + } + cxld->flags |= CXL_DECODER_F_ENABLE; + + return 0; +} + +static int cxl_decoder_reset(struct cxl_decoder *cxld) +{ + struct cxl_port *port = to_cxl_port(cxld->dev.parent); + struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev); + void __iomem *hdm = cxlhdm->regs.hdm_decoder; + int id = cxld->id; + u32 ctrl; + + if ((cxld->flags & CXL_DECODER_F_ENABLE) == 0) + return 0; + + if (port->commit_end != id) { + dev_dbg(&port->dev, + "%s: out of order reset, expected decoder%d.%d\n", + dev_name(&cxld->dev), port->id, port->commit_end); + return -EBUSY; + } + + down_read(&cxl_dpa_rwsem); + ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); + ctrl &= ~CXL_HDM_DECODER0_CTRL_COMMIT; + writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); + + writel(0, hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(id)); + writel(0, hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(id)); + writel(0, hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(id)); + writel(0, hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(id)); + up_read(&cxl_dpa_rwsem); + + port->commit_end--; + cxld->flags &= ~CXL_DECODER_F_ENABLE; + + return 0; +} + +static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, + int *target_map, void __iomem *hdm, int which, + u64 *dpa_base) +{ + struct cxl_endpoint_decoder *cxled = NULL; + u64 size, base, skip, dpa_size; + bool committed; + u32 remainder; + int i, rc; + u32 ctrl; + union { + u64 value; + unsigned char target_id[8]; + } target_list; + + if (is_endpoint_decoder(&cxld->dev)) + cxled = to_cxl_endpoint_decoder(&cxld->dev); + + ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which)); + base = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(which)); + size = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(which)); + committed = !!(ctrl & CXL_HDM_DECODER0_CTRL_COMMITTED); + cxld->commit = cxl_decoder_commit; + cxld->reset = cxl_decoder_reset; + + if (!committed) + size = 0; + if (base == U64_MAX || size == U64_MAX) { + dev_warn(&port->dev, "decoder%d.%d: Invalid resource range\n", + port->id, cxld->id); + return -ENXIO; + } + + cxld->hpa_range = (struct range) { + .start = base, + .end = base + size - 1, + }; + + /* decoders are enabled if committed */ + if (committed) { + cxld->flags |= CXL_DECODER_F_ENABLE; + if (ctrl & CXL_HDM_DECODER0_CTRL_LOCK) + cxld->flags |= CXL_DECODER_F_LOCK; + if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl)) + cxld->target_type = CXL_DECODER_EXPANDER; + else + cxld->target_type = CXL_DECODER_ACCELERATOR; + if (cxld->id != port->commit_end + 1) { + dev_warn(&port->dev, + "decoder%d.%d: Committed out of order\n", + port->id, cxld->id); + return -ENXIO; + } + + if (size == 0) { + dev_warn(&port->dev, + "decoder%d.%d: Committed with zero size\n", + port->id, cxld->id); + return -ENXIO; + } + port->commit_end = cxld->id; + } else { + /* unless / until type-2 drivers arrive, assume type-3 */ + if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl) == 0) { + ctrl |= CXL_HDM_DECODER0_CTRL_TYPE; + writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which)); + } + cxld->target_type = CXL_DECODER_EXPANDER; + } + rc = cxl_to_ways(FIELD_GET(CXL_HDM_DECODER0_CTRL_IW_MASK, ctrl), + &cxld->interleave_ways); + if (rc) { + dev_warn(&port->dev, + "decoder%d.%d: Invalid interleave ways (ctrl: %#x)\n", + port->id, cxld->id, ctrl); + return rc; + } + rc = cxl_to_granularity(FIELD_GET(CXL_HDM_DECODER0_CTRL_IG_MASK, ctrl), + &cxld->interleave_granularity); + if (rc) + return rc; + + if (!cxled) { + target_list.value = + ioread64_hi_lo(hdm + CXL_HDM_DECODER0_TL_LOW(which)); + for (i = 0; i < cxld->interleave_ways; i++) + target_map[i] = target_list.target_id[i]; + + return 0; + } + + if (!committed) + return 0; + + dpa_size = div_u64_rem(size, cxld->interleave_ways, &remainder); + if (remainder) { + dev_err(&port->dev, + "decoder%d.%d: invalid committed configuration size: %#llx ways: %d\n", + port->id, cxld->id, size, cxld->interleave_ways); + return -ENXIO; + } + skip = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_SKIP_LOW(which)); + rc = devm_cxl_dpa_reserve(cxled, *dpa_base + skip, dpa_size, skip); + if (rc) { + dev_err(&port->dev, + "decoder%d.%d: Failed to reserve DPA range %#llx - %#llx\n (%d)", + port->id, cxld->id, *dpa_base, + *dpa_base + dpa_size + skip - 1, rc); + return rc; + } + *dpa_base += dpa_size + skip; + return 0; +} + +/** + * devm_cxl_enumerate_decoders - add decoder objects per HDM register set + * @cxlhdm: Structure to populate with HDM capabilities + */ +int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm) +{ + void __iomem *hdm = cxlhdm->regs.hdm_decoder; + struct cxl_port *port = cxlhdm->port; + int i, committed; + u64 dpa_base = 0; + u32 ctrl; + + /* + * Since the register resource was recently claimed via request_region() + * be careful about trusting the "not-committed" status until the commit + * timeout has elapsed. The commit timeout is 10ms (CXL 2.0 + * 8.2.5.12.20), but double it to be tolerant of any clock skew between + * host and target. + */ + for (i = 0, committed = 0; i < cxlhdm->decoder_count; i++) { + ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(i)); + if (ctrl & CXL_HDM_DECODER0_CTRL_COMMITTED) + committed++; + } + + /* ensure that future checks of committed can be trusted */ + if (committed != cxlhdm->decoder_count) + msleep(20); + + for (i = 0; i < cxlhdm->decoder_count; i++) { + int target_map[CXL_DECODER_MAX_INTERLEAVE] = { 0 }; + int rc, target_count = cxlhdm->target_count; + struct cxl_decoder *cxld; + + if (is_cxl_endpoint(port)) { + struct cxl_endpoint_decoder *cxled; + + cxled = cxl_endpoint_decoder_alloc(port); + if (IS_ERR(cxled)) { + dev_warn(&port->dev, + "Failed to allocate the decoder\n"); + return PTR_ERR(cxled); + } + cxld = &cxled->cxld; + } else { + struct cxl_switch_decoder *cxlsd; + + cxlsd = cxl_switch_decoder_alloc(port, target_count); + if (IS_ERR(cxlsd)) { + dev_warn(&port->dev, + "Failed to allocate the decoder\n"); + return PTR_ERR(cxlsd); + } + cxld = &cxlsd->cxld; + } + + rc = init_hdm_decoder(port, cxld, target_map, hdm, i, &dpa_base); + if (rc) { + put_device(&cxld->dev); + return rc; + } + rc = add_hdm_decoder(port, cxld, target_map); + if (rc) { + dev_warn(&port->dev, + "Failed to add decoder to port\n"); + return rc; + } + } + + return 0; +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_enumerate_decoders, CXL); diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c new file mode 100644 index 000000000..0c90f1387 --- /dev/null +++ b/drivers/cxl/core/mbox.c @@ -0,0 +1,862 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2020 Intel Corporation. All rights reserved. */ +#include <linux/io-64-nonatomic-lo-hi.h> +#include <linux/security.h> +#include <linux/debugfs.h> +#include <linux/mutex.h> +#include <cxlmem.h> +#include <cxl.h> + +#include "core.h" + +static bool cxl_raw_allow_all; + +/** + * DOC: cxl mbox + * + * Core implementation of the CXL 2.0 Type-3 Memory Device Mailbox. The + * implementation is used by the cxl_pci driver to initialize the device + * and implement the cxl_mem.h IOCTL UAPI. It also implements the + * backend of the cxl_pmem_ctl() transport for LIBNVDIMM. + */ + +#define cxl_for_each_cmd(cmd) \ + for ((cmd) = &cxl_mem_commands[0]; \ + ((cmd) - cxl_mem_commands) < ARRAY_SIZE(cxl_mem_commands); (cmd)++) + +#define CXL_CMD(_id, sin, sout, _flags) \ + [CXL_MEM_COMMAND_ID_##_id] = { \ + .info = { \ + .id = CXL_MEM_COMMAND_ID_##_id, \ + .size_in = sin, \ + .size_out = sout, \ + }, \ + .opcode = CXL_MBOX_OP_##_id, \ + .flags = _flags, \ + } + +#define CXL_VARIABLE_PAYLOAD ~0U +/* + * This table defines the supported mailbox commands for the driver. This table + * is made up of a UAPI structure. Non-negative values as parameters in the + * table will be validated against the user's input. For example, if size_in is + * 0, and the user passed in 1, it is an error. + */ +static struct cxl_mem_command cxl_mem_commands[CXL_MEM_COMMAND_ID_MAX] = { + CXL_CMD(IDENTIFY, 0, 0x43, CXL_CMD_FLAG_FORCE_ENABLE), +#ifdef CONFIG_CXL_MEM_RAW_COMMANDS + CXL_CMD(RAW, CXL_VARIABLE_PAYLOAD, CXL_VARIABLE_PAYLOAD, 0), +#endif + CXL_CMD(GET_SUPPORTED_LOGS, 0, CXL_VARIABLE_PAYLOAD, CXL_CMD_FLAG_FORCE_ENABLE), + CXL_CMD(GET_FW_INFO, 0, 0x50, 0), + CXL_CMD(GET_PARTITION_INFO, 0, 0x20, 0), + CXL_CMD(GET_LSA, 0x8, CXL_VARIABLE_PAYLOAD, 0), + CXL_CMD(GET_HEALTH_INFO, 0, 0x12, 0), + CXL_CMD(GET_LOG, 0x18, CXL_VARIABLE_PAYLOAD, CXL_CMD_FLAG_FORCE_ENABLE), + CXL_CMD(SET_PARTITION_INFO, 0x0a, 0, 0), + CXL_CMD(SET_LSA, CXL_VARIABLE_PAYLOAD, 0, 0), + CXL_CMD(GET_ALERT_CONFIG, 0, 0x10, 0), + CXL_CMD(SET_ALERT_CONFIG, 0xc, 0, 0), + CXL_CMD(GET_SHUTDOWN_STATE, 0, 0x1, 0), + CXL_CMD(SET_SHUTDOWN_STATE, 0x1, 0, 0), + CXL_CMD(GET_POISON, 0x10, CXL_VARIABLE_PAYLOAD, 0), + CXL_CMD(INJECT_POISON, 0x8, 0, 0), + CXL_CMD(CLEAR_POISON, 0x48, 0, 0), + CXL_CMD(GET_SCAN_MEDIA_CAPS, 0x10, 0x4, 0), + CXL_CMD(SCAN_MEDIA, 0x11, 0, 0), + CXL_CMD(GET_SCAN_MEDIA, 0, CXL_VARIABLE_PAYLOAD, 0), +}; + +/* + * Commands that RAW doesn't permit. The rationale for each: + * + * CXL_MBOX_OP_ACTIVATE_FW: Firmware activation requires adjustment / + * coordination of transaction timeout values at the root bridge level. + * + * CXL_MBOX_OP_SET_PARTITION_INFO: The device memory map may change live + * and needs to be coordinated with HDM updates. + * + * CXL_MBOX_OP_SET_LSA: The label storage area may be cached by the + * driver and any writes from userspace invalidates those contents. + * + * CXL_MBOX_OP_SET_SHUTDOWN_STATE: Set shutdown state assumes no writes + * to the device after it is marked clean, userspace can not make that + * assertion. + * + * CXL_MBOX_OP_[GET_]SCAN_MEDIA: The kernel provides a native error list that + * is kept up to date with patrol notifications and error management. + */ +static u16 cxl_disabled_raw_commands[] = { + CXL_MBOX_OP_ACTIVATE_FW, + CXL_MBOX_OP_SET_PARTITION_INFO, + CXL_MBOX_OP_SET_LSA, + CXL_MBOX_OP_SET_SHUTDOWN_STATE, + CXL_MBOX_OP_SCAN_MEDIA, + CXL_MBOX_OP_GET_SCAN_MEDIA, +}; + +/* + * Command sets that RAW doesn't permit. All opcodes in this set are + * disabled because they pass plain text security payloads over the + * user/kernel boundary. This functionality is intended to be wrapped + * behind the keys ABI which allows for encrypted payloads in the UAPI + */ +static u8 security_command_sets[] = { + 0x44, /* Sanitize */ + 0x45, /* Persistent Memory Data-at-rest Security */ + 0x46, /* Security Passthrough */ +}; + +static bool cxl_is_security_command(u16 opcode) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(security_command_sets); i++) + if (security_command_sets[i] == (opcode >> 8)) + return true; + return false; +} + +static struct cxl_mem_command *cxl_mem_find_command(u16 opcode) +{ + struct cxl_mem_command *c; + + cxl_for_each_cmd(c) + if (c->opcode == opcode) + return c; + + return NULL; +} + +static const char *cxl_mem_opcode_to_name(u16 opcode) +{ + struct cxl_mem_command *c; + + c = cxl_mem_find_command(opcode); + if (!c) + return NULL; + + return cxl_command_names[c->info.id].name; +} + +/** + * cxl_mbox_send_cmd() - Send a mailbox command to a device. + * @cxlds: The device data for the operation + * @opcode: Opcode for the mailbox command. + * @in: The input payload for the mailbox command. + * @in_size: The length of the input payload + * @out: Caller allocated buffer for the output. + * @out_size: Expected size of output. + * + * Context: Any context. + * Return: + * * %>=0 - Number of bytes returned in @out. + * * %-E2BIG - Payload is too large for hardware. + * * %-EBUSY - Couldn't acquire exclusive mailbox access. + * * %-EFAULT - Hardware error occurred. + * * %-ENXIO - Command completed, but device reported an error. + * * %-EIO - Unexpected output size. + * + * Mailbox commands may execute successfully yet the device itself reported an + * error. While this distinction can be useful for commands from userspace, the + * kernel will only be able to use results when both are successful. + */ +int cxl_mbox_send_cmd(struct cxl_dev_state *cxlds, u16 opcode, void *in, + size_t in_size, void *out, size_t out_size) +{ + const struct cxl_mem_command *cmd = cxl_mem_find_command(opcode); + struct cxl_mbox_cmd mbox_cmd = { + .opcode = opcode, + .payload_in = in, + .size_in = in_size, + .size_out = out_size, + .payload_out = out, + }; + int rc; + + if (in_size > cxlds->payload_size || out_size > cxlds->payload_size) + return -E2BIG; + + rc = cxlds->mbox_send(cxlds, &mbox_cmd); + if (rc) + return rc; + + if (mbox_cmd.return_code != CXL_MBOX_CMD_RC_SUCCESS) + return cxl_mbox_cmd_rc2errno(&mbox_cmd); + + /* + * Variable sized commands can't be validated and so it's up to the + * caller to do that if they wish. + */ + if (cmd->info.size_out != CXL_VARIABLE_PAYLOAD) { + if (mbox_cmd.size_out != out_size) + return -EIO; + } + return 0; +} +EXPORT_SYMBOL_NS_GPL(cxl_mbox_send_cmd, CXL); + +static bool cxl_mem_raw_command_allowed(u16 opcode) +{ + int i; + + if (!IS_ENABLED(CONFIG_CXL_MEM_RAW_COMMANDS)) + return false; + + if (security_locked_down(LOCKDOWN_PCI_ACCESS)) + return false; + + if (cxl_raw_allow_all) + return true; + + if (cxl_is_security_command(opcode)) + return false; + + for (i = 0; i < ARRAY_SIZE(cxl_disabled_raw_commands); i++) + if (cxl_disabled_raw_commands[i] == opcode) + return false; + + return true; +} + +/** + * cxl_payload_from_user_allowed() - Check contents of in_payload. + * @opcode: The mailbox command opcode. + * @payload_in: Pointer to the input payload passed in from user space. + * + * Return: + * * true - payload_in passes check for @opcode. + * * false - payload_in contains invalid or unsupported values. + * + * The driver may inspect payload contents before sending a mailbox + * command from user space to the device. The intent is to reject + * commands with input payloads that are known to be unsafe. This + * check is not intended to replace the users careful selection of + * mailbox command parameters and makes no guarantee that the user + * command will succeed, nor that it is appropriate. + * + * The specific checks are determined by the opcode. + */ +static bool cxl_payload_from_user_allowed(u16 opcode, void *payload_in) +{ + switch (opcode) { + case CXL_MBOX_OP_SET_PARTITION_INFO: { + struct cxl_mbox_set_partition_info *pi = payload_in; + + if (pi->flags & CXL_SET_PARTITION_IMMEDIATE_FLAG) + return false; + break; + } + default: + break; + } + return true; +} + +static int cxl_mbox_cmd_ctor(struct cxl_mbox_cmd *mbox, + struct cxl_dev_state *cxlds, u16 opcode, + size_t in_size, size_t out_size, u64 in_payload) +{ + *mbox = (struct cxl_mbox_cmd) { + .opcode = opcode, + .size_in = in_size, + }; + + if (in_size) { + mbox->payload_in = vmemdup_user(u64_to_user_ptr(in_payload), + in_size); + if (IS_ERR(mbox->payload_in)) + return PTR_ERR(mbox->payload_in); + + if (!cxl_payload_from_user_allowed(opcode, mbox->payload_in)) { + dev_dbg(cxlds->dev, "%s: input payload not allowed\n", + cxl_mem_opcode_to_name(opcode)); + kvfree(mbox->payload_in); + return -EBUSY; + } + } + + /* Prepare to handle a full payload for variable sized output */ + if (out_size == CXL_VARIABLE_PAYLOAD) + mbox->size_out = cxlds->payload_size; + else + mbox->size_out = out_size; + + if (mbox->size_out) { + mbox->payload_out = kvzalloc(mbox->size_out, GFP_KERNEL); + if (!mbox->payload_out) { + kvfree(mbox->payload_in); + return -ENOMEM; + } + } + return 0; +} + +static void cxl_mbox_cmd_dtor(struct cxl_mbox_cmd *mbox) +{ + kvfree(mbox->payload_in); + kvfree(mbox->payload_out); +} + +static int cxl_to_mem_cmd_raw(struct cxl_mem_command *mem_cmd, + const struct cxl_send_command *send_cmd, + struct cxl_dev_state *cxlds) +{ + if (send_cmd->raw.rsvd) + return -EINVAL; + + /* + * Unlike supported commands, the output size of RAW commands + * gets passed along without further checking, so it must be + * validated here. + */ + if (send_cmd->out.size > cxlds->payload_size) + return -EINVAL; + + if (!cxl_mem_raw_command_allowed(send_cmd->raw.opcode)) + return -EPERM; + + dev_WARN_ONCE(cxlds->dev, true, "raw command path used\n"); + + *mem_cmd = (struct cxl_mem_command) { + .info = { + .id = CXL_MEM_COMMAND_ID_RAW, + .size_in = send_cmd->in.size, + .size_out = send_cmd->out.size, + }, + .opcode = send_cmd->raw.opcode + }; + + return 0; +} + +static int cxl_to_mem_cmd(struct cxl_mem_command *mem_cmd, + const struct cxl_send_command *send_cmd, + struct cxl_dev_state *cxlds) +{ + struct cxl_mem_command *c = &cxl_mem_commands[send_cmd->id]; + const struct cxl_command_info *info = &c->info; + + if (send_cmd->flags & ~CXL_MEM_COMMAND_FLAG_MASK) + return -EINVAL; + + if (send_cmd->rsvd) + return -EINVAL; + + if (send_cmd->in.rsvd || send_cmd->out.rsvd) + return -EINVAL; + + /* Check that the command is enabled for hardware */ + if (!test_bit(info->id, cxlds->enabled_cmds)) + return -ENOTTY; + + /* Check that the command is not claimed for exclusive kernel use */ + if (test_bit(info->id, cxlds->exclusive_cmds)) + return -EBUSY; + + /* Check the input buffer is the expected size */ + if ((info->size_in != CXL_VARIABLE_PAYLOAD) && + (info->size_in != send_cmd->in.size)) + return -ENOMEM; + + /* Check the output buffer is at least large enough */ + if ((info->size_out != CXL_VARIABLE_PAYLOAD) && + (send_cmd->out.size < info->size_out)) + return -ENOMEM; + + *mem_cmd = (struct cxl_mem_command) { + .info = { + .id = info->id, + .flags = info->flags, + .size_in = send_cmd->in.size, + .size_out = send_cmd->out.size, + }, + .opcode = c->opcode + }; + + return 0; +} + +/** + * cxl_validate_cmd_from_user() - Check fields for CXL_MEM_SEND_COMMAND. + * @mbox_cmd: Sanitized and populated &struct cxl_mbox_cmd. + * @cxlds: The device data for the operation + * @send_cmd: &struct cxl_send_command copied in from userspace. + * + * Return: + * * %0 - @out_cmd is ready to send. + * * %-ENOTTY - Invalid command specified. + * * %-EINVAL - Reserved fields or invalid values were used. + * * %-ENOMEM - Input or output buffer wasn't sized properly. + * * %-EPERM - Attempted to use a protected command. + * * %-EBUSY - Kernel has claimed exclusive access to this opcode + * + * The result of this command is a fully validated command in @mbox_cmd that is + * safe to send to the hardware. + */ +static int cxl_validate_cmd_from_user(struct cxl_mbox_cmd *mbox_cmd, + struct cxl_dev_state *cxlds, + const struct cxl_send_command *send_cmd) +{ + struct cxl_mem_command mem_cmd; + int rc; + + if (send_cmd->id == 0 || send_cmd->id >= CXL_MEM_COMMAND_ID_MAX) + return -ENOTTY; + + /* + * The user can never specify an input payload larger than what hardware + * supports, but output can be arbitrarily large (simply write out as + * much data as the hardware provides). + */ + if (send_cmd->in.size > cxlds->payload_size) + return -EINVAL; + + /* Sanitize and construct a cxl_mem_command */ + if (send_cmd->id == CXL_MEM_COMMAND_ID_RAW) + rc = cxl_to_mem_cmd_raw(&mem_cmd, send_cmd, cxlds); + else + rc = cxl_to_mem_cmd(&mem_cmd, send_cmd, cxlds); + + if (rc) + return rc; + + /* Sanitize and construct a cxl_mbox_cmd */ + return cxl_mbox_cmd_ctor(mbox_cmd, cxlds, mem_cmd.opcode, + mem_cmd.info.size_in, mem_cmd.info.size_out, + send_cmd->in.payload); +} + +int cxl_query_cmd(struct cxl_memdev *cxlmd, + struct cxl_mem_query_commands __user *q) +{ + struct device *dev = &cxlmd->dev; + struct cxl_mem_command *cmd; + u32 n_commands; + int j = 0; + + dev_dbg(dev, "Query IOCTL\n"); + + if (get_user(n_commands, &q->n_commands)) + return -EFAULT; + + /* returns the total number if 0 elements are requested. */ + if (n_commands == 0) + return put_user(ARRAY_SIZE(cxl_mem_commands), &q->n_commands); + + /* + * otherwise, return max(n_commands, total commands) cxl_command_info + * structures. + */ + cxl_for_each_cmd(cmd) { + const struct cxl_command_info *info = &cmd->info; + + if (copy_to_user(&q->commands[j++], info, sizeof(*info))) + return -EFAULT; + + if (j == n_commands) + break; + } + + return 0; +} + +/** + * handle_mailbox_cmd_from_user() - Dispatch a mailbox command for userspace. + * @cxlds: The device data for the operation + * @mbox_cmd: The validated mailbox command. + * @out_payload: Pointer to userspace's output payload. + * @size_out: (Input) Max payload size to copy out. + * (Output) Payload size hardware generated. + * @retval: Hardware generated return code from the operation. + * + * Return: + * * %0 - Mailbox transaction succeeded. This implies the mailbox + * protocol completed successfully not that the operation itself + * was successful. + * * %-ENOMEM - Couldn't allocate a bounce buffer. + * * %-EFAULT - Something happened with copy_to/from_user. + * * %-EINTR - Mailbox acquisition interrupted. + * * %-EXXX - Transaction level failures. + * + * Dispatches a mailbox command on behalf of a userspace request. + * The output payload is copied to userspace. + * + * See cxl_send_cmd(). + */ +static int handle_mailbox_cmd_from_user(struct cxl_dev_state *cxlds, + struct cxl_mbox_cmd *mbox_cmd, + u64 out_payload, s32 *size_out, + u32 *retval) +{ + struct device *dev = cxlds->dev; + int rc; + + dev_dbg(dev, + "Submitting %s command for user\n" + "\topcode: %x\n" + "\tsize: %zx\n", + cxl_mem_opcode_to_name(mbox_cmd->opcode), + mbox_cmd->opcode, mbox_cmd->size_in); + + rc = cxlds->mbox_send(cxlds, mbox_cmd); + if (rc) + goto out; + + /* + * @size_out contains the max size that's allowed to be written back out + * to userspace. While the payload may have written more output than + * this it will have to be ignored. + */ + if (mbox_cmd->size_out) { + dev_WARN_ONCE(dev, mbox_cmd->size_out > *size_out, + "Invalid return size\n"); + if (copy_to_user(u64_to_user_ptr(out_payload), + mbox_cmd->payload_out, mbox_cmd->size_out)) { + rc = -EFAULT; + goto out; + } + } + + *size_out = mbox_cmd->size_out; + *retval = mbox_cmd->return_code; + +out: + cxl_mbox_cmd_dtor(mbox_cmd); + return rc; +} + +int cxl_send_cmd(struct cxl_memdev *cxlmd, struct cxl_send_command __user *s) +{ + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct device *dev = &cxlmd->dev; + struct cxl_send_command send; + struct cxl_mbox_cmd mbox_cmd; + int rc; + + dev_dbg(dev, "Send IOCTL\n"); + + if (copy_from_user(&send, s, sizeof(send))) + return -EFAULT; + + rc = cxl_validate_cmd_from_user(&mbox_cmd, cxlmd->cxlds, &send); + if (rc) + return rc; + + rc = handle_mailbox_cmd_from_user(cxlds, &mbox_cmd, send.out.payload, + &send.out.size, &send.retval); + if (rc) + return rc; + + if (copy_to_user(s, &send, sizeof(send))) + return -EFAULT; + + return 0; +} + +static int cxl_xfer_log(struct cxl_dev_state *cxlds, uuid_t *uuid, u32 size, u8 *out) +{ + u32 remaining = size; + u32 offset = 0; + + while (remaining) { + u32 xfer_size = min_t(u32, remaining, cxlds->payload_size); + struct cxl_mbox_get_log log = { + .uuid = *uuid, + .offset = cpu_to_le32(offset), + .length = cpu_to_le32(xfer_size) + }; + int rc; + + rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_GET_LOG, &log, sizeof(log), + out, xfer_size); + if (rc < 0) + return rc; + + out += xfer_size; + remaining -= xfer_size; + offset += xfer_size; + } + + return 0; +} + +/** + * cxl_walk_cel() - Walk through the Command Effects Log. + * @cxlds: The device data for the operation + * @size: Length of the Command Effects Log. + * @cel: CEL + * + * Iterate over each entry in the CEL and determine if the driver supports the + * command. If so, the command is enabled for the device and can be used later. + */ +static void cxl_walk_cel(struct cxl_dev_state *cxlds, size_t size, u8 *cel) +{ + struct cxl_cel_entry *cel_entry; + const int cel_entries = size / sizeof(*cel_entry); + int i; + + cel_entry = (struct cxl_cel_entry *) cel; + + for (i = 0; i < cel_entries; i++) { + u16 opcode = le16_to_cpu(cel_entry[i].opcode); + struct cxl_mem_command *cmd = cxl_mem_find_command(opcode); + + if (!cmd) { + dev_dbg(cxlds->dev, + "Opcode 0x%04x unsupported by driver", opcode); + continue; + } + + set_bit(cmd->info.id, cxlds->enabled_cmds); + } +} + +static struct cxl_mbox_get_supported_logs *cxl_get_gsl(struct cxl_dev_state *cxlds) +{ + struct cxl_mbox_get_supported_logs *ret; + int rc; + + ret = kvmalloc(cxlds->payload_size, GFP_KERNEL); + if (!ret) + return ERR_PTR(-ENOMEM); + + rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_GET_SUPPORTED_LOGS, NULL, 0, ret, + cxlds->payload_size); + if (rc < 0) { + kvfree(ret); + return ERR_PTR(rc); + } + + return ret; +} + +enum { + CEL_UUID, + VENDOR_DEBUG_UUID, +}; + +/* See CXL 2.0 Table 170. Get Log Input Payload */ +static const uuid_t log_uuid[] = { + [CEL_UUID] = DEFINE_CXL_CEL_UUID, + [VENDOR_DEBUG_UUID] = DEFINE_CXL_VENDOR_DEBUG_UUID, +}; + +/** + * cxl_enumerate_cmds() - Enumerate commands for a device. + * @cxlds: The device data for the operation + * + * Returns 0 if enumerate completed successfully. + * + * CXL devices have optional support for certain commands. This function will + * determine the set of supported commands for the hardware and update the + * enabled_cmds bitmap in the @cxlds. + */ +int cxl_enumerate_cmds(struct cxl_dev_state *cxlds) +{ + struct cxl_mbox_get_supported_logs *gsl; + struct device *dev = cxlds->dev; + struct cxl_mem_command *cmd; + int i, rc; + + gsl = cxl_get_gsl(cxlds); + if (IS_ERR(gsl)) + return PTR_ERR(gsl); + + rc = -ENOENT; + for (i = 0; i < le16_to_cpu(gsl->entries); i++) { + u32 size = le32_to_cpu(gsl->entry[i].size); + uuid_t uuid = gsl->entry[i].uuid; + u8 *log; + + dev_dbg(dev, "Found LOG type %pU of size %d", &uuid, size); + + if (!uuid_equal(&uuid, &log_uuid[CEL_UUID])) + continue; + + log = kvmalloc(size, GFP_KERNEL); + if (!log) { + rc = -ENOMEM; + goto out; + } + + rc = cxl_xfer_log(cxlds, &uuid, size, log); + if (rc) { + kvfree(log); + goto out; + } + + cxl_walk_cel(cxlds, size, log); + kvfree(log); + + /* In case CEL was bogus, enable some default commands. */ + cxl_for_each_cmd(cmd) + if (cmd->flags & CXL_CMD_FLAG_FORCE_ENABLE) + set_bit(cmd->info.id, cxlds->enabled_cmds); + + /* Found the required CEL */ + rc = 0; + } + +out: + kvfree(gsl); + return rc; +} +EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, CXL); + +/** + * cxl_mem_get_partition_info - Get partition info + * @cxlds: The device data for the operation + * + * Retrieve the current partition info for the device specified. The active + * values are the current capacity in bytes. If not 0, the 'next' values are + * the pending values, in bytes, which take affect on next cold reset. + * + * Return: 0 if no error: or the result of the mailbox command. + * + * See CXL @8.2.9.5.2.1 Get Partition Info + */ +static int cxl_mem_get_partition_info(struct cxl_dev_state *cxlds) +{ + struct cxl_mbox_get_partition_info pi; + int rc; + + rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_GET_PARTITION_INFO, NULL, 0, + &pi, sizeof(pi)); + + if (rc) + return rc; + + cxlds->active_volatile_bytes = + le64_to_cpu(pi.active_volatile_cap) * CXL_CAPACITY_MULTIPLIER; + cxlds->active_persistent_bytes = + le64_to_cpu(pi.active_persistent_cap) * CXL_CAPACITY_MULTIPLIER; + cxlds->next_volatile_bytes = + le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER; + cxlds->next_persistent_bytes = + le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER; + + return 0; +} + +/** + * cxl_dev_state_identify() - Send the IDENTIFY command to the device. + * @cxlds: The device data for the operation + * + * Return: 0 if identify was executed successfully. + * + * This will dispatch the identify command to the device and on success populate + * structures to be exported to sysfs. + */ +int cxl_dev_state_identify(struct cxl_dev_state *cxlds) +{ + /* See CXL 2.0 Table 175 Identify Memory Device Output Payload */ + struct cxl_mbox_identify id; + int rc; + + rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_IDENTIFY, NULL, 0, &id, + sizeof(id)); + if (rc < 0) + return rc; + + cxlds->total_bytes = + le64_to_cpu(id.total_capacity) * CXL_CAPACITY_MULTIPLIER; + cxlds->volatile_only_bytes = + le64_to_cpu(id.volatile_capacity) * CXL_CAPACITY_MULTIPLIER; + cxlds->persistent_only_bytes = + le64_to_cpu(id.persistent_capacity) * CXL_CAPACITY_MULTIPLIER; + cxlds->partition_align_bytes = + le64_to_cpu(id.partition_align) * CXL_CAPACITY_MULTIPLIER; + + cxlds->lsa_size = le32_to_cpu(id.lsa_size); + memcpy(cxlds->firmware_version, id.fw_revision, sizeof(id.fw_revision)); + + return 0; +} +EXPORT_SYMBOL_NS_GPL(cxl_dev_state_identify, CXL); + +static int add_dpa_res(struct device *dev, struct resource *parent, + struct resource *res, resource_size_t start, + resource_size_t size, const char *type) +{ + int rc; + + res->name = type; + res->start = start; + res->end = start + size - 1; + res->flags = IORESOURCE_MEM; + if (resource_size(res) == 0) { + dev_dbg(dev, "DPA(%s): no capacity\n", res->name); + return 0; + } + rc = request_resource(parent, res); + if (rc) { + dev_err(dev, "DPA(%s): failed to track %pr (%d)\n", res->name, + res, rc); + return rc; + } + + dev_dbg(dev, "DPA(%s): %pr\n", res->name, res); + + return 0; +} + +int cxl_mem_create_range_info(struct cxl_dev_state *cxlds) +{ + struct device *dev = cxlds->dev; + int rc; + + cxlds->dpa_res = + (struct resource)DEFINE_RES_MEM(0, cxlds->total_bytes); + + if (cxlds->partition_align_bytes == 0) { + rc = add_dpa_res(dev, &cxlds->dpa_res, &cxlds->ram_res, 0, + cxlds->volatile_only_bytes, "ram"); + if (rc) + return rc; + return add_dpa_res(dev, &cxlds->dpa_res, &cxlds->pmem_res, + cxlds->volatile_only_bytes, + cxlds->persistent_only_bytes, "pmem"); + } + + rc = cxl_mem_get_partition_info(cxlds); + if (rc) { + dev_err(dev, "Failed to query partition information\n"); + return rc; + } + + rc = add_dpa_res(dev, &cxlds->dpa_res, &cxlds->ram_res, 0, + cxlds->active_volatile_bytes, "ram"); + if (rc) + return rc; + return add_dpa_res(dev, &cxlds->dpa_res, &cxlds->pmem_res, + cxlds->active_volatile_bytes, + cxlds->active_persistent_bytes, "pmem"); +} +EXPORT_SYMBOL_NS_GPL(cxl_mem_create_range_info, CXL); + +struct cxl_dev_state *cxl_dev_state_create(struct device *dev) +{ + struct cxl_dev_state *cxlds; + + cxlds = devm_kzalloc(dev, sizeof(*cxlds), GFP_KERNEL); + if (!cxlds) { + dev_err(dev, "No memory available\n"); + return ERR_PTR(-ENOMEM); + } + + mutex_init(&cxlds->mbox_mutex); + cxlds->dev = dev; + + return cxlds; +} +EXPORT_SYMBOL_NS_GPL(cxl_dev_state_create, CXL); + +void __init cxl_mbox_init(void) +{ + struct dentry *mbox_debugfs; + + mbox_debugfs = cxl_debugfs_create_dir("mbox"); + debugfs_create_bool("raw_allow_all", 0600, mbox_debugfs, + &cxl_raw_allow_all); +} diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c new file mode 100644 index 000000000..03cf99cce --- /dev/null +++ b/drivers/cxl/core/memdev.c @@ -0,0 +1,386 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2020 Intel Corporation. */ + +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/idr.h> +#include <linux/pci.h> +#include <cxlmem.h> +#include "core.h" + +static DECLARE_RWSEM(cxl_memdev_rwsem); + +/* + * An entire PCI topology full of devices should be enough for any + * config + */ +#define CXL_MEM_MAX_DEVS 65536 + +static int cxl_mem_major; +static DEFINE_IDA(cxl_memdev_ida); + +static void cxl_memdev_release(struct device *dev) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + + ida_free(&cxl_memdev_ida, cxlmd->id); + kfree(cxlmd); +} + +static char *cxl_memdev_devnode(struct device *dev, umode_t *mode, kuid_t *uid, + kgid_t *gid) +{ + return kasprintf(GFP_KERNEL, "cxl/%s", dev_name(dev)); +} + +static ssize_t firmware_version_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + + return sysfs_emit(buf, "%.16s\n", cxlds->firmware_version); +} +static DEVICE_ATTR_RO(firmware_version); + +static ssize_t payload_max_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + + return sysfs_emit(buf, "%zu\n", cxlds->payload_size); +} +static DEVICE_ATTR_RO(payload_max); + +static ssize_t label_storage_size_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + + return sysfs_emit(buf, "%zu\n", cxlds->lsa_size); +} +static DEVICE_ATTR_RO(label_storage_size); + +static ssize_t ram_size_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + unsigned long long len = resource_size(&cxlds->ram_res); + + return sysfs_emit(buf, "%#llx\n", len); +} + +static struct device_attribute dev_attr_ram_size = + __ATTR(size, 0444, ram_size_show, NULL); + +static ssize_t pmem_size_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + unsigned long long len = resource_size(&cxlds->pmem_res); + + return sysfs_emit(buf, "%#llx\n", len); +} + +static struct device_attribute dev_attr_pmem_size = + __ATTR(size, 0444, pmem_size_show, NULL); + +static ssize_t serial_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + + return sysfs_emit(buf, "%#llx\n", cxlds->serial); +} +static DEVICE_ATTR_RO(serial); + +static ssize_t numa_node_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", dev_to_node(dev)); +} +static DEVICE_ATTR_RO(numa_node); + +static struct attribute *cxl_memdev_attributes[] = { + &dev_attr_serial.attr, + &dev_attr_firmware_version.attr, + &dev_attr_payload_max.attr, + &dev_attr_label_storage_size.attr, + &dev_attr_numa_node.attr, + NULL, +}; + +static struct attribute *cxl_memdev_pmem_attributes[] = { + &dev_attr_pmem_size.attr, + NULL, +}; + +static struct attribute *cxl_memdev_ram_attributes[] = { + &dev_attr_ram_size.attr, + NULL, +}; + +static umode_t cxl_memdev_visible(struct kobject *kobj, struct attribute *a, + int n) +{ + if (!IS_ENABLED(CONFIG_NUMA) && a == &dev_attr_numa_node.attr) + return 0; + return a->mode; +} + +static struct attribute_group cxl_memdev_attribute_group = { + .attrs = cxl_memdev_attributes, + .is_visible = cxl_memdev_visible, +}; + +static struct attribute_group cxl_memdev_ram_attribute_group = { + .name = "ram", + .attrs = cxl_memdev_ram_attributes, +}; + +static struct attribute_group cxl_memdev_pmem_attribute_group = { + .name = "pmem", + .attrs = cxl_memdev_pmem_attributes, +}; + +static const struct attribute_group *cxl_memdev_attribute_groups[] = { + &cxl_memdev_attribute_group, + &cxl_memdev_ram_attribute_group, + &cxl_memdev_pmem_attribute_group, + NULL, +}; + +static const struct device_type cxl_memdev_type = { + .name = "cxl_memdev", + .release = cxl_memdev_release, + .devnode = cxl_memdev_devnode, + .groups = cxl_memdev_attribute_groups, +}; + +bool is_cxl_memdev(struct device *dev) +{ + return dev->type == &cxl_memdev_type; +} +EXPORT_SYMBOL_NS_GPL(is_cxl_memdev, CXL); + +/** + * set_exclusive_cxl_commands() - atomically disable user cxl commands + * @cxlds: The device state to operate on + * @cmds: bitmap of commands to mark exclusive + * + * Grab the cxl_memdev_rwsem in write mode to flush in-flight + * invocations of the ioctl path and then disable future execution of + * commands with the command ids set in @cmds. + */ +void set_exclusive_cxl_commands(struct cxl_dev_state *cxlds, unsigned long *cmds) +{ + down_write(&cxl_memdev_rwsem); + bitmap_or(cxlds->exclusive_cmds, cxlds->exclusive_cmds, cmds, + CXL_MEM_COMMAND_ID_MAX); + up_write(&cxl_memdev_rwsem); +} +EXPORT_SYMBOL_NS_GPL(set_exclusive_cxl_commands, CXL); + +/** + * clear_exclusive_cxl_commands() - atomically enable user cxl commands + * @cxlds: The device state to modify + * @cmds: bitmap of commands to mark available for userspace + */ +void clear_exclusive_cxl_commands(struct cxl_dev_state *cxlds, unsigned long *cmds) +{ + down_write(&cxl_memdev_rwsem); + bitmap_andnot(cxlds->exclusive_cmds, cxlds->exclusive_cmds, cmds, + CXL_MEM_COMMAND_ID_MAX); + up_write(&cxl_memdev_rwsem); +} +EXPORT_SYMBOL_NS_GPL(clear_exclusive_cxl_commands, CXL); + +static void cxl_memdev_shutdown(struct device *dev) +{ + struct cxl_memdev *cxlmd = to_cxl_memdev(dev); + + down_write(&cxl_memdev_rwsem); + cxlmd->cxlds = NULL; + up_write(&cxl_memdev_rwsem); +} + +static void cxl_memdev_unregister(void *_cxlmd) +{ + struct cxl_memdev *cxlmd = _cxlmd; + struct device *dev = &cxlmd->dev; + + cdev_device_del(&cxlmd->cdev, dev); + cxl_memdev_shutdown(dev); + put_device(dev); +} + +static void detach_memdev(struct work_struct *work) +{ + struct cxl_memdev *cxlmd; + + cxlmd = container_of(work, typeof(*cxlmd), detach_work); + device_release_driver(&cxlmd->dev); + put_device(&cxlmd->dev); +} + +static struct lock_class_key cxl_memdev_key; + +static struct cxl_memdev *cxl_memdev_alloc(struct cxl_dev_state *cxlds, + const struct file_operations *fops) +{ + struct cxl_memdev *cxlmd; + struct device *dev; + struct cdev *cdev; + int rc; + + cxlmd = kzalloc(sizeof(*cxlmd), GFP_KERNEL); + if (!cxlmd) + return ERR_PTR(-ENOMEM); + + rc = ida_alloc_range(&cxl_memdev_ida, 0, CXL_MEM_MAX_DEVS, GFP_KERNEL); + if (rc < 0) + goto err; + cxlmd->id = rc; + + dev = &cxlmd->dev; + device_initialize(dev); + lockdep_set_class(&dev->mutex, &cxl_memdev_key); + dev->parent = cxlds->dev; + dev->bus = &cxl_bus_type; + dev->devt = MKDEV(cxl_mem_major, cxlmd->id); + dev->type = &cxl_memdev_type; + device_set_pm_not_required(dev); + INIT_WORK(&cxlmd->detach_work, detach_memdev); + + cdev = &cxlmd->cdev; + cdev_init(cdev, fops); + return cxlmd; + +err: + kfree(cxlmd); + return ERR_PTR(rc); +} + +static long __cxl_memdev_ioctl(struct cxl_memdev *cxlmd, unsigned int cmd, + unsigned long arg) +{ + switch (cmd) { + case CXL_MEM_QUERY_COMMANDS: + return cxl_query_cmd(cxlmd, (void __user *)arg); + case CXL_MEM_SEND_COMMAND: + return cxl_send_cmd(cxlmd, (void __user *)arg); + default: + return -ENOTTY; + } +} + +static long cxl_memdev_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct cxl_memdev *cxlmd = file->private_data; + int rc = -ENXIO; + + down_read(&cxl_memdev_rwsem); + if (cxlmd->cxlds) + rc = __cxl_memdev_ioctl(cxlmd, cmd, arg); + up_read(&cxl_memdev_rwsem); + + return rc; +} + +static int cxl_memdev_open(struct inode *inode, struct file *file) +{ + struct cxl_memdev *cxlmd = + container_of(inode->i_cdev, typeof(*cxlmd), cdev); + + get_device(&cxlmd->dev); + file->private_data = cxlmd; + + return 0; +} + +static int cxl_memdev_release_file(struct inode *inode, struct file *file) +{ + struct cxl_memdev *cxlmd = + container_of(inode->i_cdev, typeof(*cxlmd), cdev); + + put_device(&cxlmd->dev); + + return 0; +} + +static const struct file_operations cxl_memdev_fops = { + .owner = THIS_MODULE, + .unlocked_ioctl = cxl_memdev_ioctl, + .open = cxl_memdev_open, + .release = cxl_memdev_release_file, + .compat_ioctl = compat_ptr_ioctl, + .llseek = noop_llseek, +}; + +struct cxl_memdev *devm_cxl_add_memdev(struct cxl_dev_state *cxlds) +{ + struct cxl_memdev *cxlmd; + struct device *dev; + struct cdev *cdev; + int rc; + + cxlmd = cxl_memdev_alloc(cxlds, &cxl_memdev_fops); + if (IS_ERR(cxlmd)) + return cxlmd; + + dev = &cxlmd->dev; + rc = dev_set_name(dev, "mem%d", cxlmd->id); + if (rc) + goto err; + + /* + * Activate ioctl operations, no cxl_memdev_rwsem manipulation + * needed as this is ordered with cdev_add() publishing the device. + */ + cxlmd->cxlds = cxlds; + + cdev = &cxlmd->cdev; + rc = cdev_device_add(cdev, dev); + if (rc) + goto err; + + rc = devm_add_action_or_reset(cxlds->dev, cxl_memdev_unregister, cxlmd); + if (rc) + return ERR_PTR(rc); + return cxlmd; + +err: + /* + * The cdev was briefly live, shutdown any ioctl operations that + * saw that state. + */ + cxl_memdev_shutdown(dev); + put_device(dev); + return ERR_PTR(rc); +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_add_memdev, CXL); + +__init int cxl_memdev_init(void) +{ + dev_t devt; + int rc; + + rc = alloc_chrdev_region(&devt, 0, CXL_MEM_MAX_DEVS, "cxl"); + if (rc) + return rc; + + cxl_mem_major = MAJOR(devt); + + return 0; +} + +void cxl_memdev_exit(void) +{ + unregister_chrdev_region(MKDEV(cxl_mem_major, 0), CXL_MEM_MAX_DEVS); +} diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c new file mode 100644 index 000000000..003a44132 --- /dev/null +++ b/drivers/cxl/core/pci.c @@ -0,0 +1,702 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2021 Intel Corporation. All rights reserved. */ +#include <linux/io-64-nonatomic-lo-hi.h> +#include <linux/device.h> +#include <linux/delay.h> +#include <linux/pci.h> +#include <linux/pci-doe.h> +#include <cxlpci.h> +#include <cxlmem.h> +#include <cxl.h> +#include "core.h" + +/** + * DOC: cxl core pci + * + * Compute Express Link protocols are layered on top of PCIe. CXL core provides + * a set of helpers for CXL interactions which occur via PCIe. + */ + +static unsigned short media_ready_timeout = 60; +module_param(media_ready_timeout, ushort, 0644); +MODULE_PARM_DESC(media_ready_timeout, "seconds to wait for media ready"); + +struct cxl_walk_context { + struct pci_bus *bus; + struct cxl_port *port; + int type; + int error; + int count; +}; + +static int match_add_dports(struct pci_dev *pdev, void *data) +{ + struct cxl_walk_context *ctx = data; + struct cxl_port *port = ctx->port; + int type = pci_pcie_type(pdev); + struct cxl_register_map map; + struct cxl_dport *dport; + u32 lnkcap, port_num; + int rc; + + if (pdev->bus != ctx->bus) + return 0; + if (!pci_is_pcie(pdev)) + return 0; + if (type != ctx->type) + return 0; + if (pci_read_config_dword(pdev, pci_pcie_cap(pdev) + PCI_EXP_LNKCAP, + &lnkcap)) + return 0; + + rc = cxl_find_regblock(pdev, CXL_REGLOC_RBI_COMPONENT, &map); + if (rc) + dev_dbg(&port->dev, "failed to find component registers\n"); + + port_num = FIELD_GET(PCI_EXP_LNKCAP_PN, lnkcap); + dport = devm_cxl_add_dport(port, &pdev->dev, port_num, + cxl_regmap_to_base(pdev, &map)); + if (IS_ERR(dport)) { + ctx->error = PTR_ERR(dport); + return PTR_ERR(dport); + } + ctx->count++; + + dev_dbg(&port->dev, "add dport%d: %s\n", port_num, dev_name(&pdev->dev)); + + return 0; +} + +/** + * devm_cxl_port_enumerate_dports - enumerate downstream ports of the upstream port + * @port: cxl_port whose ->uport is the upstream of dports to be enumerated + * + * Returns a positive number of dports enumerated or a negative error + * code. + */ +int devm_cxl_port_enumerate_dports(struct cxl_port *port) +{ + struct pci_bus *bus = cxl_port_to_pci_bus(port); + struct cxl_walk_context ctx; + int type; + + if (!bus) + return -ENXIO; + + if (pci_is_root_bus(bus)) + type = PCI_EXP_TYPE_ROOT_PORT; + else + type = PCI_EXP_TYPE_DOWNSTREAM; + + ctx = (struct cxl_walk_context) { + .port = port, + .bus = bus, + .type = type, + }; + pci_walk_bus(bus, match_add_dports, &ctx); + + if (ctx.count == 0) + return -ENODEV; + if (ctx.error) + return ctx.error; + return ctx.count; +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_port_enumerate_dports, CXL); + +static int cxl_dvsec_mem_range_valid(struct cxl_dev_state *cxlds, int id) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int d = cxlds->cxl_dvsec; + bool valid = false; + int rc, i; + u32 temp; + + if (id > CXL_DVSEC_RANGE_MAX) + return -EINVAL; + + /* Check MEM INFO VALID bit first, give up after 1s */ + i = 1; + do { + rc = pci_read_config_dword(pdev, + d + CXL_DVSEC_RANGE_SIZE_LOW(id), + &temp); + if (rc) + return rc; + + valid = FIELD_GET(CXL_DVSEC_MEM_INFO_VALID, temp); + if (valid) + break; + msleep(1000); + } while (i--); + + if (!valid) { + dev_err(&pdev->dev, + "Timeout awaiting memory range %d valid after 1s.\n", + id); + return -ETIMEDOUT; + } + + return 0; +} + +static int cxl_dvsec_mem_range_active(struct cxl_dev_state *cxlds, int id) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int d = cxlds->cxl_dvsec; + bool active = false; + int rc, i; + u32 temp; + + if (id > CXL_DVSEC_RANGE_MAX) + return -EINVAL; + + /* Check MEM ACTIVE bit, up to 60s timeout by default */ + for (i = media_ready_timeout; i; i--) { + rc = pci_read_config_dword( + pdev, d + CXL_DVSEC_RANGE_SIZE_LOW(id), &temp); + if (rc) + return rc; + + active = FIELD_GET(CXL_DVSEC_MEM_ACTIVE, temp); + if (active) + break; + msleep(1000); + } + + if (!active) { + dev_err(&pdev->dev, + "timeout awaiting memory active after %d seconds\n", + media_ready_timeout); + return -ETIMEDOUT; + } + + return 0; +} + +/* + * Wait up to @media_ready_timeout for the device to report memory + * active. + */ +int cxl_await_media_ready(struct cxl_dev_state *cxlds) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int d = cxlds->cxl_dvsec; + int rc, i, hdm_count; + u64 md_status; + u16 cap; + + rc = pci_read_config_word(pdev, + d + CXL_DVSEC_CAP_OFFSET, &cap); + if (rc) + return rc; + + hdm_count = FIELD_GET(CXL_DVSEC_HDM_COUNT_MASK, cap); + for (i = 0; i < hdm_count; i++) { + rc = cxl_dvsec_mem_range_valid(cxlds, i); + if (rc) + return rc; + } + + for (i = 0; i < hdm_count; i++) { + rc = cxl_dvsec_mem_range_active(cxlds, i); + if (rc) + return rc; + } + + md_status = readq(cxlds->regs.memdev + CXLMDEV_STATUS_OFFSET); + if (!CXLMDEV_READY(md_status)) + return -EIO; + + return 0; +} +EXPORT_SYMBOL_NS_GPL(cxl_await_media_ready, CXL); + +static int wait_for_valid(struct cxl_dev_state *cxlds) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int d = cxlds->cxl_dvsec, rc; + u32 val; + + /* + * Memory_Info_Valid: When set, indicates that the CXL Range 1 Size high + * and Size Low registers are valid. Must be set within 1 second of + * deassertion of reset to CXL device. Likely it is already set by the + * time this runs, but otherwise give a 1.5 second timeout in case of + * clock skew. + */ + rc = pci_read_config_dword(pdev, d + CXL_DVSEC_RANGE_SIZE_LOW(0), &val); + if (rc) + return rc; + + if (val & CXL_DVSEC_MEM_INFO_VALID) + return 0; + + msleep(1500); + + rc = pci_read_config_dword(pdev, d + CXL_DVSEC_RANGE_SIZE_LOW(0), &val); + if (rc) + return rc; + + if (val & CXL_DVSEC_MEM_INFO_VALID) + return 0; + + return -ETIMEDOUT; +} + +static int cxl_set_mem_enable(struct cxl_dev_state *cxlds, u16 val) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int d = cxlds->cxl_dvsec; + u16 ctrl; + int rc; + + rc = pci_read_config_word(pdev, d + CXL_DVSEC_CTRL_OFFSET, &ctrl); + if (rc < 0) + return rc; + + if ((ctrl & CXL_DVSEC_MEM_ENABLE) == val) + return 1; + ctrl &= ~CXL_DVSEC_MEM_ENABLE; + ctrl |= val; + + rc = pci_write_config_word(pdev, d + CXL_DVSEC_CTRL_OFFSET, ctrl); + if (rc < 0) + return rc; + + return 0; +} + +static void clear_mem_enable(void *cxlds) +{ + cxl_set_mem_enable(cxlds, 0); +} + +static int devm_cxl_enable_mem(struct device *host, struct cxl_dev_state *cxlds) +{ + int rc; + + rc = cxl_set_mem_enable(cxlds, CXL_DVSEC_MEM_ENABLE); + if (rc < 0) + return rc; + if (rc > 0) + return 0; + return devm_add_action_or_reset(host, clear_mem_enable, cxlds); +} + +static bool range_contains(struct range *r1, struct range *r2) +{ + return r1->start <= r2->start && r1->end >= r2->end; +} + +/* require dvsec ranges to be covered by a locked platform window */ +static int dvsec_range_allowed(struct device *dev, void *arg) +{ + struct range *dev_range = arg; + struct cxl_decoder *cxld; + + if (!is_root_decoder(dev)) + return 0; + + cxld = to_cxl_decoder(dev); + + if (!(cxld->flags & CXL_DECODER_F_LOCK)) + return 0; + if (!(cxld->flags & CXL_DECODER_F_RAM)) + return 0; + + return range_contains(&cxld->hpa_range, dev_range); +} + +static void disable_hdm(void *_cxlhdm) +{ + u32 global_ctrl; + struct cxl_hdm *cxlhdm = _cxlhdm; + void __iomem *hdm = cxlhdm->regs.hdm_decoder; + + global_ctrl = readl(hdm + CXL_HDM_DECODER_CTRL_OFFSET); + writel(global_ctrl & ~CXL_HDM_DECODER_ENABLE, + hdm + CXL_HDM_DECODER_CTRL_OFFSET); +} + +static int devm_cxl_enable_hdm(struct device *host, struct cxl_hdm *cxlhdm) +{ + void __iomem *hdm = cxlhdm->regs.hdm_decoder; + u32 global_ctrl; + + global_ctrl = readl(hdm + CXL_HDM_DECODER_CTRL_OFFSET); + writel(global_ctrl | CXL_HDM_DECODER_ENABLE, + hdm + CXL_HDM_DECODER_CTRL_OFFSET); + + return devm_add_action_or_reset(host, disable_hdm, cxlhdm); +} + +static bool __cxl_hdm_decode_init(struct cxl_dev_state *cxlds, + struct cxl_hdm *cxlhdm, + struct cxl_endpoint_dvsec_info *info) +{ + void __iomem *hdm = cxlhdm->regs.hdm_decoder; + struct cxl_port *port = cxlhdm->port; + struct device *dev = cxlds->dev; + struct cxl_port *root; + int i, rc, allowed; + u32 global_ctrl; + + global_ctrl = readl(hdm + CXL_HDM_DECODER_CTRL_OFFSET); + + /* + * If the HDM Decoder Capability is already enabled then assume + * that some other agent like platform firmware set it up. + */ + if (global_ctrl & CXL_HDM_DECODER_ENABLE) { + rc = devm_cxl_enable_mem(&port->dev, cxlds); + if (rc) + return false; + return true; + } + + root = to_cxl_port(port->dev.parent); + while (!is_cxl_root(root) && is_cxl_port(root->dev.parent)) + root = to_cxl_port(root->dev.parent); + if (!is_cxl_root(root)) { + dev_err(dev, "Failed to acquire root port for HDM enable\n"); + return false; + } + + for (i = 0, allowed = 0; info->mem_enabled && i < info->ranges; i++) { + struct device *cxld_dev; + + cxld_dev = device_find_child(&root->dev, &info->dvsec_range[i], + dvsec_range_allowed); + if (!cxld_dev) { + dev_dbg(dev, "DVSEC Range%d denied by platform\n", i); + continue; + } + dev_dbg(dev, "DVSEC Range%d allowed by platform\n", i); + put_device(cxld_dev); + allowed++; + } + + if (!allowed) { + cxl_set_mem_enable(cxlds, 0); + info->mem_enabled = 0; + } + + /* + * Per CXL 2.0 Section 8.1.3.8.3 and 8.1.3.8.4 DVSEC CXL Range 1 Base + * [High,Low] when HDM operation is enabled the range register values + * are ignored by the device, but the spec also recommends matching the + * DVSEC Range 1,2 to HDM Decoder Range 0,1. So, non-zero info->ranges + * are expected even though Linux does not require or maintain that + * match. If at least one DVSEC range is enabled and allowed, skip HDM + * Decoder Capability Enable. + */ + if (info->mem_enabled) + return false; + + rc = devm_cxl_enable_hdm(&port->dev, cxlhdm); + if (rc) + return false; + + rc = devm_cxl_enable_mem(&port->dev, cxlds); + if (rc) + return false; + + return true; +} + +/** + * cxl_hdm_decode_init() - Setup HDM decoding for the endpoint + * @cxlds: Device state + * @cxlhdm: Mapped HDM decoder Capability + * + * Try to enable the endpoint's HDM Decoder Capability + */ +int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + struct cxl_endpoint_dvsec_info info = { 0 }; + int hdm_count, rc, i, ranges = 0; + struct device *dev = &pdev->dev; + int d = cxlds->cxl_dvsec; + u16 cap, ctrl; + + if (!d) { + dev_dbg(dev, "No DVSEC Capability\n"); + return -ENXIO; + } + + rc = pci_read_config_word(pdev, d + CXL_DVSEC_CAP_OFFSET, &cap); + if (rc) + return rc; + + rc = pci_read_config_word(pdev, d + CXL_DVSEC_CTRL_OFFSET, &ctrl); + if (rc) + return rc; + + if (!(cap & CXL_DVSEC_MEM_CAPABLE)) { + dev_dbg(dev, "Not MEM Capable\n"); + return -ENXIO; + } + + /* + * It is not allowed by spec for MEM.capable to be set and have 0 legacy + * HDM decoders (values > 2 are also undefined as of CXL 2.0). As this + * driver is for a spec defined class code which must be CXL.mem + * capable, there is no point in continuing to enable CXL.mem. + */ + hdm_count = FIELD_GET(CXL_DVSEC_HDM_COUNT_MASK, cap); + if (!hdm_count || hdm_count > 2) + return -EINVAL; + + rc = wait_for_valid(cxlds); + if (rc) { + dev_dbg(dev, "Failure awaiting MEM_INFO_VALID (%d)\n", rc); + return rc; + } + + /* + * The current DVSEC values are moot if the memory capability is + * disabled, and they will remain moot after the HDM Decoder + * capability is enabled. + */ + info.mem_enabled = FIELD_GET(CXL_DVSEC_MEM_ENABLE, ctrl); + if (!info.mem_enabled) + goto hdm_init; + + for (i = 0; i < hdm_count; i++) { + u64 base, size; + u32 temp; + + rc = pci_read_config_dword( + pdev, d + CXL_DVSEC_RANGE_SIZE_HIGH(i), &temp); + if (rc) + return rc; + + size = (u64)temp << 32; + + rc = pci_read_config_dword( + pdev, d + CXL_DVSEC_RANGE_SIZE_LOW(i), &temp); + if (rc) + return rc; + + size |= temp & CXL_DVSEC_MEM_SIZE_LOW_MASK; + + rc = pci_read_config_dword( + pdev, d + CXL_DVSEC_RANGE_BASE_HIGH(i), &temp); + if (rc) + return rc; + + base = (u64)temp << 32; + + rc = pci_read_config_dword( + pdev, d + CXL_DVSEC_RANGE_BASE_LOW(i), &temp); + if (rc) + return rc; + + base |= temp & CXL_DVSEC_MEM_BASE_LOW_MASK; + + info.dvsec_range[i] = (struct range) { + .start = base, + .end = base + size - 1 + }; + + if (size) + ranges++; + } + + info.ranges = ranges; + + /* + * If DVSEC ranges are being used instead of HDM decoder registers there + * is no use in trying to manage those. + */ +hdm_init: + if (!__cxl_hdm_decode_init(cxlds, cxlhdm, &info)) { + dev_err(dev, + "Legacy range registers configuration prevents HDM operation.\n"); + return -EBUSY; + } + + return 0; +} +EXPORT_SYMBOL_NS_GPL(cxl_hdm_decode_init, CXL); + +#define CXL_DOE_TABLE_ACCESS_REQ_CODE 0x000000ff +#define CXL_DOE_TABLE_ACCESS_REQ_CODE_READ 0 +#define CXL_DOE_TABLE_ACCESS_TABLE_TYPE 0x0000ff00 +#define CXL_DOE_TABLE_ACCESS_TABLE_TYPE_CDATA 0 +#define CXL_DOE_TABLE_ACCESS_ENTRY_HANDLE 0xffff0000 +#define CXL_DOE_TABLE_ACCESS_LAST_ENTRY 0xffff +#define CXL_DOE_PROTOCOL_TABLE_ACCESS 2 + +static struct pci_doe_mb *find_cdat_doe(struct device *uport) +{ + struct cxl_memdev *cxlmd; + struct cxl_dev_state *cxlds; + unsigned long index; + void *entry; + + cxlmd = to_cxl_memdev(uport); + cxlds = cxlmd->cxlds; + + xa_for_each(&cxlds->doe_mbs, index, entry) { + struct pci_doe_mb *cur = entry; + + if (pci_doe_supports_prot(cur, PCI_DVSEC_VENDOR_ID_CXL, + CXL_DOE_PROTOCOL_TABLE_ACCESS)) + return cur; + } + + return NULL; +} + +#define CDAT_DOE_REQ(entry_handle) cpu_to_le32 \ + (FIELD_PREP(CXL_DOE_TABLE_ACCESS_REQ_CODE, \ + CXL_DOE_TABLE_ACCESS_REQ_CODE_READ) | \ + FIELD_PREP(CXL_DOE_TABLE_ACCESS_TABLE_TYPE, \ + CXL_DOE_TABLE_ACCESS_TABLE_TYPE_CDATA) | \ + FIELD_PREP(CXL_DOE_TABLE_ACCESS_ENTRY_HANDLE, (entry_handle))) + +static void cxl_doe_task_complete(struct pci_doe_task *task) +{ + complete(task->private); +} + +struct cdat_doe_task { + __le32 request_pl; + __le32 response_pl[32]; + struct completion c; + struct pci_doe_task task; +}; + +#define DECLARE_CDAT_DOE_TASK(req, cdt) \ +struct cdat_doe_task cdt = { \ + .c = COMPLETION_INITIALIZER_ONSTACK(cdt.c), \ + .request_pl = req, \ + .task = { \ + .prot.vid = PCI_DVSEC_VENDOR_ID_CXL, \ + .prot.type = CXL_DOE_PROTOCOL_TABLE_ACCESS, \ + .request_pl = &cdt.request_pl, \ + .request_pl_sz = sizeof(cdt.request_pl), \ + .response_pl = cdt.response_pl, \ + .response_pl_sz = sizeof(cdt.response_pl), \ + .complete = cxl_doe_task_complete, \ + .private = &cdt.c, \ + } \ +} + +static int cxl_cdat_get_length(struct device *dev, + struct pci_doe_mb *cdat_doe, + size_t *length) +{ + DECLARE_CDAT_DOE_TASK(CDAT_DOE_REQ(0), t); + int rc; + + rc = pci_doe_submit_task(cdat_doe, &t.task); + if (rc < 0) { + dev_err(dev, "DOE submit failed: %d", rc); + return rc; + } + wait_for_completion(&t.c); + if (t.task.rv < 2 * sizeof(__le32)) + return -EIO; + + *length = le32_to_cpu(t.response_pl[1]); + dev_dbg(dev, "CDAT length %zu\n", *length); + + return 0; +} + +static int cxl_cdat_read_table(struct device *dev, + struct pci_doe_mb *cdat_doe, + struct cxl_cdat *cdat) +{ + size_t length = cdat->length; + __le32 *data = cdat->table; + int entry_handle = 0; + + do { + DECLARE_CDAT_DOE_TASK(CDAT_DOE_REQ(entry_handle), t); + struct cdat_entry_header *entry; + size_t entry_dw; + int rc; + + rc = pci_doe_submit_task(cdat_doe, &t.task); + if (rc < 0) { + dev_err(dev, "DOE submit failed: %d", rc); + return rc; + } + wait_for_completion(&t.c); + + /* 1 DW Table Access Response Header + CDAT entry */ + entry = (struct cdat_entry_header *)(t.response_pl + 1); + if ((entry_handle == 0 && + t.task.rv != sizeof(__le32) + sizeof(struct cdat_header)) || + (entry_handle > 0 && + (t.task.rv < sizeof(__le32) + sizeof(*entry) || + t.task.rv != sizeof(__le32) + le16_to_cpu(entry->length)))) + return -EIO; + + /* Get the CXL table access header entry handle */ + entry_handle = FIELD_GET(CXL_DOE_TABLE_ACCESS_ENTRY_HANDLE, + le32_to_cpu(t.response_pl[0])); + entry_dw = t.task.rv / sizeof(__le32); + /* Skip Header */ + entry_dw -= 1; + entry_dw = min(length / sizeof(__le32), entry_dw); + /* Prevent length < 1 DW from causing a buffer overflow */ + if (entry_dw) { + memcpy(data, entry, entry_dw * sizeof(__le32)); + length -= entry_dw * sizeof(__le32); + data += entry_dw; + } + } while (entry_handle != CXL_DOE_TABLE_ACCESS_LAST_ENTRY); + + /* Length in CDAT header may exceed concatenation of CDAT entries */ + cdat->length -= length; + + return 0; +} + +/** + * read_cdat_data - Read the CDAT data on this port + * @port: Port to read data from + * + * This call will sleep waiting for responses from the DOE mailbox. + */ +void read_cdat_data(struct cxl_port *port) +{ + struct pci_doe_mb *cdat_doe; + struct device *dev = &port->dev; + struct device *uport = port->uport; + size_t cdat_length; + int rc; + + cdat_doe = find_cdat_doe(uport); + if (!cdat_doe) { + dev_dbg(dev, "No CDAT mailbox\n"); + return; + } + + port->cdat_available = true; + + if (cxl_cdat_get_length(dev, cdat_doe, &cdat_length)) { + dev_dbg(dev, "No CDAT length\n"); + return; + } + + port->cdat.table = devm_kzalloc(dev, cdat_length, GFP_KERNEL); + if (!port->cdat.table) + return; + + port->cdat.length = cdat_length; + rc = cxl_cdat_read_table(dev, cdat_doe, &port->cdat); + if (rc) { + /* Don't leave table data allocated on error */ + devm_kfree(dev, port->cdat.table); + port->cdat.table = NULL; + port->cdat.length = 0; + dev_err(dev, "CDAT data read error\n"); + } +} +EXPORT_SYMBOL_NS_GPL(read_cdat_data, CXL); diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c new file mode 100644 index 000000000..36aa5070d --- /dev/null +++ b/drivers/cxl/core/pmem.c @@ -0,0 +1,285 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2020 Intel Corporation. */ +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/idr.h> +#include <cxlmem.h> +#include <cxl.h> +#include "core.h" + +/** + * DOC: cxl pmem + * + * The core CXL PMEM infrastructure supports persistent memory + * provisioning and serves as a bridge to the LIBNVDIMM subsystem. A CXL + * 'bridge' device is added at the root of a CXL device topology if + * platform firmware advertises at least one persistent memory capable + * CXL window. That root-level bridge corresponds to a LIBNVDIMM 'bus' + * device. Then for each cxl_memdev in the CXL device topology a bridge + * device is added to host a LIBNVDIMM dimm object. When these bridges + * are registered native LIBNVDIMM uapis are translated to CXL + * operations, for example, namespace label access commands. + */ + +static DEFINE_IDA(cxl_nvdimm_bridge_ida); + +static void cxl_nvdimm_bridge_release(struct device *dev) +{ + struct cxl_nvdimm_bridge *cxl_nvb = to_cxl_nvdimm_bridge(dev); + + ida_free(&cxl_nvdimm_bridge_ida, cxl_nvb->id); + kfree(cxl_nvb); +} + +static const struct attribute_group *cxl_nvdimm_bridge_attribute_groups[] = { + &cxl_base_attribute_group, + NULL, +}; + +const struct device_type cxl_nvdimm_bridge_type = { + .name = "cxl_nvdimm_bridge", + .release = cxl_nvdimm_bridge_release, + .groups = cxl_nvdimm_bridge_attribute_groups, +}; + +struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev) +{ + if (dev_WARN_ONCE(dev, dev->type != &cxl_nvdimm_bridge_type, + "not a cxl_nvdimm_bridge device\n")) + return NULL; + return container_of(dev, struct cxl_nvdimm_bridge, dev); +} +EXPORT_SYMBOL_NS_GPL(to_cxl_nvdimm_bridge, CXL); + +bool is_cxl_nvdimm_bridge(struct device *dev) +{ + return dev->type == &cxl_nvdimm_bridge_type; +} +EXPORT_SYMBOL_NS_GPL(is_cxl_nvdimm_bridge, CXL); + +static int match_nvdimm_bridge(struct device *dev, void *data) +{ + return is_cxl_nvdimm_bridge(dev); +} + +struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct device *start) +{ + struct cxl_port *port = find_cxl_root(start); + struct device *dev; + + if (!port) + return NULL; + + dev = device_find_child(&port->dev, NULL, match_nvdimm_bridge); + put_device(&port->dev); + + if (!dev) + return NULL; + + return to_cxl_nvdimm_bridge(dev); +} +EXPORT_SYMBOL_NS_GPL(cxl_find_nvdimm_bridge, CXL); + +static struct lock_class_key cxl_nvdimm_bridge_key; + +static struct cxl_nvdimm_bridge *cxl_nvdimm_bridge_alloc(struct cxl_port *port) +{ + struct cxl_nvdimm_bridge *cxl_nvb; + struct device *dev; + int rc; + + cxl_nvb = kzalloc(sizeof(*cxl_nvb), GFP_KERNEL); + if (!cxl_nvb) + return ERR_PTR(-ENOMEM); + + rc = ida_alloc(&cxl_nvdimm_bridge_ida, GFP_KERNEL); + if (rc < 0) + goto err; + cxl_nvb->id = rc; + + dev = &cxl_nvb->dev; + cxl_nvb->port = port; + cxl_nvb->state = CXL_NVB_NEW; + device_initialize(dev); + lockdep_set_class(&dev->mutex, &cxl_nvdimm_bridge_key); + device_set_pm_not_required(dev); + dev->parent = &port->dev; + dev->bus = &cxl_bus_type; + dev->type = &cxl_nvdimm_bridge_type; + + return cxl_nvb; + +err: + kfree(cxl_nvb); + return ERR_PTR(rc); +} + +static void unregister_nvb(void *_cxl_nvb) +{ + struct cxl_nvdimm_bridge *cxl_nvb = _cxl_nvb; + bool flush; + + /* + * If the bridge was ever activated then there might be in-flight state + * work to flush. Once the state has been changed to 'dead' then no new + * work can be queued by user-triggered bind. + */ + device_lock(&cxl_nvb->dev); + flush = cxl_nvb->state != CXL_NVB_NEW; + cxl_nvb->state = CXL_NVB_DEAD; + device_unlock(&cxl_nvb->dev); + + /* + * Even though the device core will trigger device_release_driver() + * before the unregister, it does not know about the fact that + * cxl_nvdimm_bridge_driver defers ->remove() work. So, do the driver + * release not and flush it before tearing down the nvdimm device + * hierarchy. + */ + device_release_driver(&cxl_nvb->dev); + if (flush) + flush_work(&cxl_nvb->state_work); + device_unregister(&cxl_nvb->dev); +} + +/** + * devm_cxl_add_nvdimm_bridge() - add the root of a LIBNVDIMM topology + * @host: platform firmware root device + * @port: CXL port at the root of a CXL topology + * + * Return: bridge device that can host cxl_nvdimm objects + */ +struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host, + struct cxl_port *port) +{ + struct cxl_nvdimm_bridge *cxl_nvb; + struct device *dev; + int rc; + + if (!IS_ENABLED(CONFIG_CXL_PMEM)) + return ERR_PTR(-ENXIO); + + cxl_nvb = cxl_nvdimm_bridge_alloc(port); + if (IS_ERR(cxl_nvb)) + return cxl_nvb; + + dev = &cxl_nvb->dev; + rc = dev_set_name(dev, "nvdimm-bridge%d", cxl_nvb->id); + if (rc) + goto err; + + rc = device_add(dev); + if (rc) + goto err; + + rc = devm_add_action_or_reset(host, unregister_nvb, cxl_nvb); + if (rc) + return ERR_PTR(rc); + + return cxl_nvb; + +err: + put_device(dev); + return ERR_PTR(rc); +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_add_nvdimm_bridge, CXL); + +static void cxl_nvdimm_release(struct device *dev) +{ + struct cxl_nvdimm *cxl_nvd = to_cxl_nvdimm(dev); + + xa_destroy(&cxl_nvd->pmem_regions); + kfree(cxl_nvd); +} + +static const struct attribute_group *cxl_nvdimm_attribute_groups[] = { + &cxl_base_attribute_group, + NULL, +}; + +const struct device_type cxl_nvdimm_type = { + .name = "cxl_nvdimm", + .release = cxl_nvdimm_release, + .groups = cxl_nvdimm_attribute_groups, +}; + +bool is_cxl_nvdimm(struct device *dev) +{ + return dev->type == &cxl_nvdimm_type; +} +EXPORT_SYMBOL_NS_GPL(is_cxl_nvdimm, CXL); + +struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev) +{ + if (dev_WARN_ONCE(dev, !is_cxl_nvdimm(dev), + "not a cxl_nvdimm device\n")) + return NULL; + return container_of(dev, struct cxl_nvdimm, dev); +} +EXPORT_SYMBOL_NS_GPL(to_cxl_nvdimm, CXL); + +static struct lock_class_key cxl_nvdimm_key; + +static struct cxl_nvdimm *cxl_nvdimm_alloc(struct cxl_memdev *cxlmd) +{ + struct cxl_nvdimm *cxl_nvd; + struct device *dev; + + cxl_nvd = kzalloc(sizeof(*cxl_nvd), GFP_KERNEL); + if (!cxl_nvd) + return ERR_PTR(-ENOMEM); + + dev = &cxl_nvd->dev; + cxl_nvd->cxlmd = cxlmd; + xa_init(&cxl_nvd->pmem_regions); + device_initialize(dev); + lockdep_set_class(&dev->mutex, &cxl_nvdimm_key); + device_set_pm_not_required(dev); + dev->parent = &cxlmd->dev; + dev->bus = &cxl_bus_type; + dev->type = &cxl_nvdimm_type; + + return cxl_nvd; +} + +static void cxl_nvd_unregister(void *dev) +{ + device_unregister(dev); +} + +/** + * devm_cxl_add_nvdimm() - add a bridge between a cxl_memdev and an nvdimm + * @host: same host as @cxlmd + * @cxlmd: cxl_memdev instance that will perform LIBNVDIMM operations + * + * Return: 0 on success negative error code on failure. + */ +int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd) +{ + struct cxl_nvdimm *cxl_nvd; + struct device *dev; + int rc; + + cxl_nvd = cxl_nvdimm_alloc(cxlmd); + if (IS_ERR(cxl_nvd)) + return PTR_ERR(cxl_nvd); + + dev = &cxl_nvd->dev; + rc = dev_set_name(dev, "pmem%d", cxlmd->id); + if (rc) + goto err; + + rc = device_add(dev); + if (rc) + goto err; + + dev_dbg(host, "%s: register %s\n", dev_name(dev->parent), + dev_name(dev)); + + return devm_add_action_or_reset(host, cxl_nvd_unregister, dev); + +err: + put_device(dev); + return rc; +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_add_nvdimm, CXL); diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c new file mode 100644 index 000000000..1f1483a9e --- /dev/null +++ b/drivers/cxl/core/port.c @@ -0,0 +1,1894 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2020 Intel Corporation. All rights reserved. */ +#include <linux/io-64-nonatomic-lo-hi.h> +#include <linux/memregion.h> +#include <linux/workqueue.h> +#include <linux/debugfs.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/idr.h> +#include <cxlmem.h> +#include <cxlpci.h> +#include <cxl.h> +#include "core.h" + +/** + * DOC: cxl core + * + * The CXL core provides a set of interfaces that can be consumed by CXL aware + * drivers. The interfaces allow for creation, modification, and destruction of + * regions, memory devices, ports, and decoders. CXL aware drivers must register + * with the CXL core via these interfaces in order to be able to participate in + * cross-device interleave coordination. The CXL core also establishes and + * maintains the bridge to the nvdimm subsystem. + * + * CXL core introduces sysfs hierarchy to control the devices that are + * instantiated by the core. + */ + +static DEFINE_IDA(cxl_port_ida); +static DEFINE_XARRAY(cxl_root_buses); + +static ssize_t devtype_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%s\n", dev->type->name); +} +static DEVICE_ATTR_RO(devtype); + +static int cxl_device_id(struct device *dev) +{ + if (dev->type == &cxl_nvdimm_bridge_type) + return CXL_DEVICE_NVDIMM_BRIDGE; + if (dev->type == &cxl_nvdimm_type) + return CXL_DEVICE_NVDIMM; + if (dev->type == CXL_PMEM_REGION_TYPE()) + return CXL_DEVICE_PMEM_REGION; + if (is_cxl_port(dev)) { + if (is_cxl_root(to_cxl_port(dev))) + return CXL_DEVICE_ROOT; + return CXL_DEVICE_PORT; + } + if (is_cxl_memdev(dev)) + return CXL_DEVICE_MEMORY_EXPANDER; + if (dev->type == CXL_REGION_TYPE()) + return CXL_DEVICE_REGION; + return 0; +} + +static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, CXL_MODALIAS_FMT "\n", cxl_device_id(dev)); +} +static DEVICE_ATTR_RO(modalias); + +static struct attribute *cxl_base_attributes[] = { + &dev_attr_devtype.attr, + &dev_attr_modalias.attr, + NULL, +}; + +struct attribute_group cxl_base_attribute_group = { + .attrs = cxl_base_attributes, +}; + +static ssize_t start_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_decoder *cxld = to_cxl_decoder(dev); + + return sysfs_emit(buf, "%#llx\n", cxld->hpa_range.start); +} +static DEVICE_ATTR_ADMIN_RO(start); + +static ssize_t size_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_decoder *cxld = to_cxl_decoder(dev); + + return sysfs_emit(buf, "%#llx\n", range_len(&cxld->hpa_range)); +} +static DEVICE_ATTR_RO(size); + +#define CXL_DECODER_FLAG_ATTR(name, flag) \ +static ssize_t name##_show(struct device *dev, \ + struct device_attribute *attr, char *buf) \ +{ \ + struct cxl_decoder *cxld = to_cxl_decoder(dev); \ + \ + return sysfs_emit(buf, "%s\n", \ + (cxld->flags & (flag)) ? "1" : "0"); \ +} \ +static DEVICE_ATTR_RO(name) + +CXL_DECODER_FLAG_ATTR(cap_pmem, CXL_DECODER_F_PMEM); +CXL_DECODER_FLAG_ATTR(cap_ram, CXL_DECODER_F_RAM); +CXL_DECODER_FLAG_ATTR(cap_type2, CXL_DECODER_F_TYPE2); +CXL_DECODER_FLAG_ATTR(cap_type3, CXL_DECODER_F_TYPE3); +CXL_DECODER_FLAG_ATTR(locked, CXL_DECODER_F_LOCK); + +static ssize_t target_type_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_decoder *cxld = to_cxl_decoder(dev); + + switch (cxld->target_type) { + case CXL_DECODER_ACCELERATOR: + return sysfs_emit(buf, "accelerator\n"); + case CXL_DECODER_EXPANDER: + return sysfs_emit(buf, "expander\n"); + } + return -ENXIO; +} +static DEVICE_ATTR_RO(target_type); + +static ssize_t emit_target_list(struct cxl_switch_decoder *cxlsd, char *buf) +{ + struct cxl_decoder *cxld = &cxlsd->cxld; + ssize_t offset = 0; + int i, rc = 0; + + for (i = 0; i < cxld->interleave_ways; i++) { + struct cxl_dport *dport = cxlsd->target[i]; + struct cxl_dport *next = NULL; + + if (!dport) + break; + + if (i + 1 < cxld->interleave_ways) + next = cxlsd->target[i + 1]; + rc = sysfs_emit_at(buf, offset, "%d%s", dport->port_id, + next ? "," : ""); + if (rc < 0) + return rc; + offset += rc; + } + + return offset; +} + +static ssize_t target_list_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_switch_decoder *cxlsd = to_cxl_switch_decoder(dev); + ssize_t offset; + unsigned int seq; + int rc; + + do { + seq = read_seqbegin(&cxlsd->target_lock); + rc = emit_target_list(cxlsd, buf); + } while (read_seqretry(&cxlsd->target_lock, seq)); + + if (rc < 0) + return rc; + offset = rc; + + rc = sysfs_emit_at(buf, offset, "\n"); + if (rc < 0) + return rc; + + return offset + rc; +} +static DEVICE_ATTR_RO(target_list); + +static ssize_t mode_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); + + switch (cxled->mode) { + case CXL_DECODER_RAM: + return sysfs_emit(buf, "ram\n"); + case CXL_DECODER_PMEM: + return sysfs_emit(buf, "pmem\n"); + case CXL_DECODER_NONE: + return sysfs_emit(buf, "none\n"); + case CXL_DECODER_MIXED: + default: + return sysfs_emit(buf, "mixed\n"); + } +} + +static ssize_t mode_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); + enum cxl_decoder_mode mode; + ssize_t rc; + + if (sysfs_streq(buf, "pmem")) + mode = CXL_DECODER_PMEM; + else if (sysfs_streq(buf, "ram")) + mode = CXL_DECODER_RAM; + else + return -EINVAL; + + rc = cxl_dpa_set_mode(cxled, mode); + if (rc) + return rc; + + return len; +} +static DEVICE_ATTR_RW(mode); + +static ssize_t dpa_resource_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); + u64 base = cxl_dpa_resource_start(cxled); + + return sysfs_emit(buf, "%#llx\n", base); +} +static DEVICE_ATTR_RO(dpa_resource); + +static ssize_t dpa_size_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); + resource_size_t size = cxl_dpa_size(cxled); + + return sysfs_emit(buf, "%pa\n", &size); +} + +static ssize_t dpa_size_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); + unsigned long long size; + ssize_t rc; + + rc = kstrtoull(buf, 0, &size); + if (rc) + return rc; + + if (!IS_ALIGNED(size, SZ_256M)) + return -EINVAL; + + rc = cxl_dpa_free(cxled); + if (rc) + return rc; + + if (size == 0) + return len; + + rc = cxl_dpa_alloc(cxled, size); + if (rc) + return rc; + + return len; +} +static DEVICE_ATTR_RW(dpa_size); + +static ssize_t interleave_granularity_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct cxl_decoder *cxld = to_cxl_decoder(dev); + + return sysfs_emit(buf, "%d\n", cxld->interleave_granularity); +} + +static DEVICE_ATTR_RO(interleave_granularity); + +static ssize_t interleave_ways_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_decoder *cxld = to_cxl_decoder(dev); + + return sysfs_emit(buf, "%d\n", cxld->interleave_ways); +} + +static DEVICE_ATTR_RO(interleave_ways); + +static struct attribute *cxl_decoder_base_attrs[] = { + &dev_attr_start.attr, + &dev_attr_size.attr, + &dev_attr_locked.attr, + &dev_attr_interleave_granularity.attr, + &dev_attr_interleave_ways.attr, + NULL, +}; + +static struct attribute_group cxl_decoder_base_attribute_group = { + .attrs = cxl_decoder_base_attrs, +}; + +static struct attribute *cxl_decoder_root_attrs[] = { + &dev_attr_cap_pmem.attr, + &dev_attr_cap_ram.attr, + &dev_attr_cap_type2.attr, + &dev_attr_cap_type3.attr, + &dev_attr_target_list.attr, + SET_CXL_REGION_ATTR(create_pmem_region) + SET_CXL_REGION_ATTR(delete_region) + NULL, +}; + +static bool can_create_pmem(struct cxl_root_decoder *cxlrd) +{ + unsigned long flags = CXL_DECODER_F_TYPE3 | CXL_DECODER_F_PMEM; + + return (cxlrd->cxlsd.cxld.flags & flags) == flags; +} + +static umode_t cxl_root_decoder_visible(struct kobject *kobj, struct attribute *a, int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev); + + if (a == CXL_REGION_ATTR(create_pmem_region) && !can_create_pmem(cxlrd)) + return 0; + + if (a == CXL_REGION_ATTR(delete_region) && !can_create_pmem(cxlrd)) + return 0; + + return a->mode; +} + +static struct attribute_group cxl_decoder_root_attribute_group = { + .attrs = cxl_decoder_root_attrs, + .is_visible = cxl_root_decoder_visible, +}; + +static const struct attribute_group *cxl_decoder_root_attribute_groups[] = { + &cxl_decoder_root_attribute_group, + &cxl_decoder_base_attribute_group, + &cxl_base_attribute_group, + NULL, +}; + +static struct attribute *cxl_decoder_switch_attrs[] = { + &dev_attr_target_type.attr, + &dev_attr_target_list.attr, + SET_CXL_REGION_ATTR(region) + NULL, +}; + +static struct attribute_group cxl_decoder_switch_attribute_group = { + .attrs = cxl_decoder_switch_attrs, +}; + +static const struct attribute_group *cxl_decoder_switch_attribute_groups[] = { + &cxl_decoder_switch_attribute_group, + &cxl_decoder_base_attribute_group, + &cxl_base_attribute_group, + NULL, +}; + +static struct attribute *cxl_decoder_endpoint_attrs[] = { + &dev_attr_target_type.attr, + &dev_attr_mode.attr, + &dev_attr_dpa_size.attr, + &dev_attr_dpa_resource.attr, + SET_CXL_REGION_ATTR(region) + NULL, +}; + +static struct attribute_group cxl_decoder_endpoint_attribute_group = { + .attrs = cxl_decoder_endpoint_attrs, +}; + +static const struct attribute_group *cxl_decoder_endpoint_attribute_groups[] = { + &cxl_decoder_base_attribute_group, + &cxl_decoder_endpoint_attribute_group, + &cxl_base_attribute_group, + NULL, +}; + +static void __cxl_decoder_release(struct cxl_decoder *cxld) +{ + struct cxl_port *port = to_cxl_port(cxld->dev.parent); + + ida_free(&port->decoder_ida, cxld->id); + put_device(&port->dev); +} + +static void cxl_endpoint_decoder_release(struct device *dev) +{ + struct cxl_endpoint_decoder *cxled = to_cxl_endpoint_decoder(dev); + + __cxl_decoder_release(&cxled->cxld); + kfree(cxled); +} + +static void cxl_switch_decoder_release(struct device *dev) +{ + struct cxl_switch_decoder *cxlsd = to_cxl_switch_decoder(dev); + + __cxl_decoder_release(&cxlsd->cxld); + kfree(cxlsd); +} + +struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev) +{ + if (dev_WARN_ONCE(dev, !is_root_decoder(dev), + "not a cxl_root_decoder device\n")) + return NULL; + return container_of(dev, struct cxl_root_decoder, cxlsd.cxld.dev); +} +EXPORT_SYMBOL_NS_GPL(to_cxl_root_decoder, CXL); + +static void cxl_root_decoder_release(struct device *dev) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev); + + if (atomic_read(&cxlrd->region_id) >= 0) + memregion_free(atomic_read(&cxlrd->region_id)); + __cxl_decoder_release(&cxlrd->cxlsd.cxld); + kfree(cxlrd); +} + +static const struct device_type cxl_decoder_endpoint_type = { + .name = "cxl_decoder_endpoint", + .release = cxl_endpoint_decoder_release, + .groups = cxl_decoder_endpoint_attribute_groups, +}; + +static const struct device_type cxl_decoder_switch_type = { + .name = "cxl_decoder_switch", + .release = cxl_switch_decoder_release, + .groups = cxl_decoder_switch_attribute_groups, +}; + +static const struct device_type cxl_decoder_root_type = { + .name = "cxl_decoder_root", + .release = cxl_root_decoder_release, + .groups = cxl_decoder_root_attribute_groups, +}; + +bool is_endpoint_decoder(struct device *dev) +{ + return dev->type == &cxl_decoder_endpoint_type; +} + +bool is_root_decoder(struct device *dev) +{ + return dev->type == &cxl_decoder_root_type; +} +EXPORT_SYMBOL_NS_GPL(is_root_decoder, CXL); + +bool is_switch_decoder(struct device *dev) +{ + return is_root_decoder(dev) || dev->type == &cxl_decoder_switch_type; +} +EXPORT_SYMBOL_NS_GPL(is_switch_decoder, CXL); + +struct cxl_decoder *to_cxl_decoder(struct device *dev) +{ + if (dev_WARN_ONCE(dev, + !is_switch_decoder(dev) && !is_endpoint_decoder(dev), + "not a cxl_decoder device\n")) + return NULL; + return container_of(dev, struct cxl_decoder, dev); +} +EXPORT_SYMBOL_NS_GPL(to_cxl_decoder, CXL); + +struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev) +{ + if (dev_WARN_ONCE(dev, !is_endpoint_decoder(dev), + "not a cxl_endpoint_decoder device\n")) + return NULL; + return container_of(dev, struct cxl_endpoint_decoder, cxld.dev); +} +EXPORT_SYMBOL_NS_GPL(to_cxl_endpoint_decoder, CXL); + +struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev) +{ + if (dev_WARN_ONCE(dev, !is_switch_decoder(dev), + "not a cxl_switch_decoder device\n")) + return NULL; + return container_of(dev, struct cxl_switch_decoder, cxld.dev); +} +EXPORT_SYMBOL_NS_GPL(to_cxl_switch_decoder, CXL); + +static void cxl_ep_release(struct cxl_ep *ep) +{ + put_device(ep->ep); + kfree(ep); +} + +static void cxl_ep_remove(struct cxl_port *port, struct cxl_ep *ep) +{ + if (!ep) + return; + xa_erase(&port->endpoints, (unsigned long) ep->ep); + cxl_ep_release(ep); +} + +static void cxl_port_release(struct device *dev) +{ + struct cxl_port *port = to_cxl_port(dev); + unsigned long index; + struct cxl_ep *ep; + + xa_for_each(&port->endpoints, index, ep) + cxl_ep_remove(port, ep); + xa_destroy(&port->endpoints); + xa_destroy(&port->dports); + xa_destroy(&port->regions); + ida_free(&cxl_port_ida, port->id); + kfree(port); +} + +static const struct attribute_group *cxl_port_attribute_groups[] = { + &cxl_base_attribute_group, + NULL, +}; + +static const struct device_type cxl_port_type = { + .name = "cxl_port", + .release = cxl_port_release, + .groups = cxl_port_attribute_groups, +}; + +bool is_cxl_port(struct device *dev) +{ + return dev->type == &cxl_port_type; +} +EXPORT_SYMBOL_NS_GPL(is_cxl_port, CXL); + +struct cxl_port *to_cxl_port(struct device *dev) +{ + if (dev_WARN_ONCE(dev, dev->type != &cxl_port_type, + "not a cxl_port device\n")) + return NULL; + return container_of(dev, struct cxl_port, dev); +} +EXPORT_SYMBOL_NS_GPL(to_cxl_port, CXL); + +static void unregister_port(void *_port) +{ + struct cxl_port *port = _port; + struct cxl_port *parent; + struct device *lock_dev; + + if (is_cxl_root(port)) + parent = NULL; + else + parent = to_cxl_port(port->dev.parent); + + /* + * CXL root port's and the first level of ports are unregistered + * under the platform firmware device lock, all other ports are + * unregistered while holding their parent port lock. + */ + if (!parent) + lock_dev = port->uport; + else if (is_cxl_root(parent)) + lock_dev = parent->uport; + else + lock_dev = &parent->dev; + + device_lock_assert(lock_dev); + port->dead = true; + device_unregister(&port->dev); +} + +static void cxl_unlink_uport(void *_port) +{ + struct cxl_port *port = _port; + + sysfs_remove_link(&port->dev.kobj, "uport"); +} + +static int devm_cxl_link_uport(struct device *host, struct cxl_port *port) +{ + int rc; + + rc = sysfs_create_link(&port->dev.kobj, &port->uport->kobj, "uport"); + if (rc) + return rc; + return devm_add_action_or_reset(host, cxl_unlink_uport, port); +} + +static struct lock_class_key cxl_port_key; + +static struct cxl_port *cxl_port_alloc(struct device *uport, + resource_size_t component_reg_phys, + struct cxl_dport *parent_dport) +{ + struct cxl_port *port; + struct device *dev; + int rc; + + port = kzalloc(sizeof(*port), GFP_KERNEL); + if (!port) + return ERR_PTR(-ENOMEM); + + rc = ida_alloc(&cxl_port_ida, GFP_KERNEL); + if (rc < 0) + goto err; + port->id = rc; + port->uport = uport; + + /* + * The top-level cxl_port "cxl_root" does not have a cxl_port as + * its parent and it does not have any corresponding component + * registers as its decode is described by a fixed platform + * description. + */ + dev = &port->dev; + if (parent_dport) { + struct cxl_port *parent_port = parent_dport->port; + struct cxl_port *iter; + + dev->parent = &parent_port->dev; + port->depth = parent_port->depth + 1; + port->parent_dport = parent_dport; + + /* + * walk to the host bridge, or the first ancestor that knows + * the host bridge + */ + iter = port; + while (!iter->host_bridge && + !is_cxl_root(to_cxl_port(iter->dev.parent))) + iter = to_cxl_port(iter->dev.parent); + if (iter->host_bridge) + port->host_bridge = iter->host_bridge; + else + port->host_bridge = iter->uport; + dev_dbg(uport, "host-bridge: %s\n", dev_name(port->host_bridge)); + } else + dev->parent = uport; + + port->component_reg_phys = component_reg_phys; + ida_init(&port->decoder_ida); + port->hdm_end = -1; + port->commit_end = -1; + xa_init(&port->dports); + xa_init(&port->endpoints); + xa_init(&port->regions); + + device_initialize(dev); + lockdep_set_class_and_subclass(&dev->mutex, &cxl_port_key, port->depth); + device_set_pm_not_required(dev); + dev->bus = &cxl_bus_type; + dev->type = &cxl_port_type; + + return port; + +err: + kfree(port); + return ERR_PTR(rc); +} + +static struct cxl_port *__devm_cxl_add_port(struct device *host, + struct device *uport, + resource_size_t component_reg_phys, + struct cxl_dport *parent_dport) +{ + struct cxl_port *port; + struct device *dev; + int rc; + + port = cxl_port_alloc(uport, component_reg_phys, parent_dport); + if (IS_ERR(port)) + return port; + + dev = &port->dev; + if (is_cxl_memdev(uport)) + rc = dev_set_name(dev, "endpoint%d", port->id); + else if (parent_dport) + rc = dev_set_name(dev, "port%d", port->id); + else + rc = dev_set_name(dev, "root%d", port->id); + if (rc) + goto err; + + rc = device_add(dev); + if (rc) + goto err; + + rc = devm_add_action_or_reset(host, unregister_port, port); + if (rc) + return ERR_PTR(rc); + + rc = devm_cxl_link_uport(host, port); + if (rc) + return ERR_PTR(rc); + + return port; + +err: + put_device(dev); + return ERR_PTR(rc); +} + +/** + * devm_cxl_add_port - register a cxl_port in CXL memory decode hierarchy + * @host: host device for devm operations + * @uport: "physical" device implementing this upstream port + * @component_reg_phys: (optional) for configurable cxl_port instances + * @parent_dport: next hop up in the CXL memory decode hierarchy + */ +struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport, + resource_size_t component_reg_phys, + struct cxl_dport *parent_dport) +{ + struct cxl_port *port, *parent_port; + + port = __devm_cxl_add_port(host, uport, component_reg_phys, + parent_dport); + + parent_port = parent_dport ? parent_dport->port : NULL; + if (IS_ERR(port)) { + dev_dbg(uport, "Failed to add%s%s%s: %ld\n", + parent_port ? " port to " : "", + parent_port ? dev_name(&parent_port->dev) : "", + parent_port ? "" : " root port", + PTR_ERR(port)); + } else { + dev_dbg(uport, "%s added%s%s%s\n", + dev_name(&port->dev), + parent_port ? " to " : "", + parent_port ? dev_name(&parent_port->dev) : "", + parent_port ? "" : " (root port)"); + } + + return port; +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_add_port, CXL); + +struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port) +{ + /* There is no pci_bus associated with a CXL platform-root port */ + if (is_cxl_root(port)) + return NULL; + + if (dev_is_pci(port->uport)) { + struct pci_dev *pdev = to_pci_dev(port->uport); + + return pdev->subordinate; + } + + return xa_load(&cxl_root_buses, (unsigned long)port->uport); +} +EXPORT_SYMBOL_NS_GPL(cxl_port_to_pci_bus, CXL); + +static void unregister_pci_bus(void *uport) +{ + xa_erase(&cxl_root_buses, (unsigned long)uport); +} + +int devm_cxl_register_pci_bus(struct device *host, struct device *uport, + struct pci_bus *bus) +{ + int rc; + + if (dev_is_pci(uport)) + return -EINVAL; + + rc = xa_insert(&cxl_root_buses, (unsigned long)uport, bus, GFP_KERNEL); + if (rc) + return rc; + return devm_add_action_or_reset(host, unregister_pci_bus, uport); +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_register_pci_bus, CXL); + +static bool dev_is_cxl_root_child(struct device *dev) +{ + struct cxl_port *port, *parent; + + if (!is_cxl_port(dev)) + return false; + + port = to_cxl_port(dev); + if (is_cxl_root(port)) + return false; + + parent = to_cxl_port(port->dev.parent); + if (is_cxl_root(parent)) + return true; + + return false; +} + +/* Find a 2nd level CXL port that has a dport that is an ancestor of @match */ +static int match_root_child(struct device *dev, const void *match) +{ + const struct device *iter = NULL; + struct cxl_dport *dport; + struct cxl_port *port; + + if (!dev_is_cxl_root_child(dev)) + return 0; + + port = to_cxl_port(dev); + iter = match; + while (iter) { + dport = cxl_find_dport_by_dev(port, iter); + if (dport) + break; + iter = iter->parent; + } + + return !!iter; +} + +struct cxl_port *find_cxl_root(struct device *dev) +{ + struct device *port_dev; + struct cxl_port *root; + + port_dev = bus_find_device(&cxl_bus_type, NULL, dev, match_root_child); + if (!port_dev) + return NULL; + + root = to_cxl_port(port_dev->parent); + get_device(&root->dev); + put_device(port_dev); + return root; +} +EXPORT_SYMBOL_NS_GPL(find_cxl_root, CXL); + +static struct cxl_dport *find_dport(struct cxl_port *port, int id) +{ + struct cxl_dport *dport; + unsigned long index; + + device_lock_assert(&port->dev); + xa_for_each(&port->dports, index, dport) + if (dport->port_id == id) + return dport; + return NULL; +} + +static int add_dport(struct cxl_port *port, struct cxl_dport *new) +{ + struct cxl_dport *dup; + int rc; + + device_lock_assert(&port->dev); + dup = find_dport(port, new->port_id); + if (dup) { + dev_err(&port->dev, + "unable to add dport%d-%s non-unique port id (%s)\n", + new->port_id, dev_name(new->dport), + dev_name(dup->dport)); + return -EBUSY; + } + + rc = xa_insert(&port->dports, (unsigned long)new->dport, new, + GFP_KERNEL); + if (rc) + return rc; + + port->nr_dports++; + return 0; +} + +/* + * Since root-level CXL dports cannot be enumerated by PCI they are not + * enumerated by the common port driver that acquires the port lock over + * dport add/remove. Instead, root dports are manually added by a + * platform driver and cond_cxl_root_lock() is used to take the missing + * port lock in that case. + */ +static void cond_cxl_root_lock(struct cxl_port *port) +{ + if (is_cxl_root(port)) + device_lock(&port->dev); +} + +static void cond_cxl_root_unlock(struct cxl_port *port) +{ + if (is_cxl_root(port)) + device_unlock(&port->dev); +} + +static void cxl_dport_remove(void *data) +{ + struct cxl_dport *dport = data; + struct cxl_port *port = dport->port; + + xa_erase(&port->dports, (unsigned long) dport->dport); + put_device(dport->dport); +} + +static void cxl_dport_unlink(void *data) +{ + struct cxl_dport *dport = data; + struct cxl_port *port = dport->port; + char link_name[CXL_TARGET_STRLEN]; + + sprintf(link_name, "dport%d", dport->port_id); + sysfs_remove_link(&port->dev.kobj, link_name); +} + +/** + * devm_cxl_add_dport - append downstream port data to a cxl_port + * @port: the cxl_port that references this dport + * @dport_dev: firmware or PCI device representing the dport + * @port_id: identifier for this dport in a decoder's target list + * @component_reg_phys: optional location of CXL component registers + * + * Note that dports are appended to the devm release action's of the + * either the port's host (for root ports), or the port itself (for + * switch ports) + */ +struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port, + struct device *dport_dev, int port_id, + resource_size_t component_reg_phys) +{ + char link_name[CXL_TARGET_STRLEN]; + struct cxl_dport *dport; + struct device *host; + int rc; + + if (is_cxl_root(port)) + host = port->uport; + else + host = &port->dev; + + if (!host->driver) { + dev_WARN_ONCE(&port->dev, 1, "dport:%s bad devm context\n", + dev_name(dport_dev)); + return ERR_PTR(-ENXIO); + } + + if (snprintf(link_name, CXL_TARGET_STRLEN, "dport%d", port_id) >= + CXL_TARGET_STRLEN) + return ERR_PTR(-EINVAL); + + dport = devm_kzalloc(host, sizeof(*dport), GFP_KERNEL); + if (!dport) + return ERR_PTR(-ENOMEM); + + dport->dport = dport_dev; + dport->port_id = port_id; + dport->component_reg_phys = component_reg_phys; + dport->port = port; + + cond_cxl_root_lock(port); + rc = add_dport(port, dport); + cond_cxl_root_unlock(port); + if (rc) + return ERR_PTR(rc); + + get_device(dport_dev); + rc = devm_add_action_or_reset(host, cxl_dport_remove, dport); + if (rc) + return ERR_PTR(rc); + + rc = sysfs_create_link(&port->dev.kobj, &dport_dev->kobj, link_name); + if (rc) + return ERR_PTR(rc); + + rc = devm_add_action_or_reset(host, cxl_dport_unlink, dport); + if (rc) + return ERR_PTR(rc); + + return dport; +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_add_dport, CXL); + +static int add_ep(struct cxl_ep *new) +{ + struct cxl_port *port = new->dport->port; + int rc; + + device_lock(&port->dev); + if (port->dead) { + device_unlock(&port->dev); + return -ENXIO; + } + rc = xa_insert(&port->endpoints, (unsigned long)new->ep, new, + GFP_KERNEL); + device_unlock(&port->dev); + + return rc; +} + +/** + * cxl_add_ep - register an endpoint's interest in a port + * @dport: the dport that routes to @ep_dev + * @ep_dev: device representing the endpoint + * + * Intermediate CXL ports are scanned based on the arrival of endpoints. + * When those endpoints depart the port can be destroyed once all + * endpoints that care about that port have been removed. + */ +static int cxl_add_ep(struct cxl_dport *dport, struct device *ep_dev) +{ + struct cxl_ep *ep; + int rc; + + ep = kzalloc(sizeof(*ep), GFP_KERNEL); + if (!ep) + return -ENOMEM; + + ep->ep = get_device(ep_dev); + ep->dport = dport; + + rc = add_ep(ep); + if (rc) + cxl_ep_release(ep); + return rc; +} + +struct cxl_find_port_ctx { + const struct device *dport_dev; + const struct cxl_port *parent_port; + struct cxl_dport **dport; +}; + +static int match_port_by_dport(struct device *dev, const void *data) +{ + const struct cxl_find_port_ctx *ctx = data; + struct cxl_dport *dport; + struct cxl_port *port; + + if (!is_cxl_port(dev)) + return 0; + if (ctx->parent_port && dev->parent != &ctx->parent_port->dev) + return 0; + + port = to_cxl_port(dev); + dport = cxl_find_dport_by_dev(port, ctx->dport_dev); + if (ctx->dport) + *ctx->dport = dport; + return dport != NULL; +} + +static struct cxl_port *__find_cxl_port(struct cxl_find_port_ctx *ctx) +{ + struct device *dev; + + if (!ctx->dport_dev) + return NULL; + + dev = bus_find_device(&cxl_bus_type, NULL, ctx, match_port_by_dport); + if (dev) + return to_cxl_port(dev); + return NULL; +} + +static struct cxl_port *find_cxl_port(struct device *dport_dev, + struct cxl_dport **dport) +{ + struct cxl_find_port_ctx ctx = { + .dport_dev = dport_dev, + .dport = dport, + }; + struct cxl_port *port; + + port = __find_cxl_port(&ctx); + return port; +} + +static struct cxl_port *find_cxl_port_at(struct cxl_port *parent_port, + struct device *dport_dev, + struct cxl_dport **dport) +{ + struct cxl_find_port_ctx ctx = { + .dport_dev = dport_dev, + .parent_port = parent_port, + .dport = dport, + }; + struct cxl_port *port; + + port = __find_cxl_port(&ctx); + return port; +} + +/* + * All users of grandparent() are using it to walk PCIe-like swich port + * hierarchy. A PCIe switch is comprised of a bridge device representing the + * upstream switch port and N bridges representing downstream switch ports. When + * bridges stack the grand-parent of a downstream switch port is another + * downstream switch port in the immediate ancestor switch. + */ +static struct device *grandparent(struct device *dev) +{ + if (dev && dev->parent) + return dev->parent->parent; + return NULL; +} + +static void delete_endpoint(void *data) +{ + struct cxl_memdev *cxlmd = data; + struct cxl_port *endpoint = dev_get_drvdata(&cxlmd->dev); + struct cxl_port *parent_port; + struct device *parent; + + parent_port = cxl_mem_find_port(cxlmd, NULL); + if (!parent_port) + goto out; + parent = &parent_port->dev; + + device_lock(parent); + if (parent->driver && !endpoint->dead) { + devm_release_action(parent, cxl_unlink_uport, endpoint); + devm_release_action(parent, unregister_port, endpoint); + } + device_unlock(parent); + put_device(parent); +out: + put_device(&endpoint->dev); +} + +int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint) +{ + struct device *dev = &cxlmd->dev; + + get_device(&endpoint->dev); + dev_set_drvdata(dev, endpoint); + return devm_add_action_or_reset(dev, delete_endpoint, cxlmd); +} +EXPORT_SYMBOL_NS_GPL(cxl_endpoint_autoremove, CXL); + +/* + * The natural end of life of a non-root 'cxl_port' is when its parent port goes + * through a ->remove() event ("top-down" unregistration). The unnatural trigger + * for a port to be unregistered is when all memdevs beneath that port have gone + * through ->remove(). This "bottom-up" removal selectively removes individual + * child ports manually. This depends on devm_cxl_add_port() to not change is + * devm action registration order, and for dports to have already been + * destroyed by reap_dports(). + */ +static void delete_switch_port(struct cxl_port *port) +{ + devm_release_action(port->dev.parent, cxl_unlink_uport, port); + devm_release_action(port->dev.parent, unregister_port, port); +} + +static void reap_dports(struct cxl_port *port) +{ + struct cxl_dport *dport; + unsigned long index; + + device_lock_assert(&port->dev); + + xa_for_each(&port->dports, index, dport) { + devm_release_action(&port->dev, cxl_dport_unlink, dport); + devm_release_action(&port->dev, cxl_dport_remove, dport); + devm_kfree(&port->dev, dport); + } +} + +static void cxl_detach_ep(void *data) +{ + struct cxl_memdev *cxlmd = data; + struct device *iter; + + for (iter = &cxlmd->dev; iter; iter = grandparent(iter)) { + struct device *dport_dev = grandparent(iter); + struct cxl_port *port, *parent_port; + struct cxl_ep *ep; + bool died = false; + + if (!dport_dev) + break; + + port = find_cxl_port(dport_dev, NULL); + if (!port) + continue; + + if (is_cxl_root(port)) { + put_device(&port->dev); + continue; + } + + parent_port = to_cxl_port(port->dev.parent); + device_lock(&parent_port->dev); + if (!parent_port->dev.driver) { + /* + * The bottom-up race to delete the port lost to a + * top-down port disable, give up here, because the + * parent_port ->remove() will have cleaned up all + * descendants. + */ + device_unlock(&parent_port->dev); + put_device(&port->dev); + continue; + } + + device_lock(&port->dev); + ep = cxl_ep_load(port, cxlmd); + dev_dbg(&cxlmd->dev, "disconnect %s from %s\n", + ep ? dev_name(ep->ep) : "", dev_name(&port->dev)); + cxl_ep_remove(port, ep); + if (ep && !port->dead && xa_empty(&port->endpoints) && + !is_cxl_root(parent_port)) { + /* + * This was the last ep attached to a dynamically + * enumerated port. Block new cxl_add_ep() and garbage + * collect the port. + */ + died = true; + port->dead = true; + reap_dports(port); + } + device_unlock(&port->dev); + + if (died) { + dev_dbg(&cxlmd->dev, "delete %s\n", + dev_name(&port->dev)); + delete_switch_port(port); + } + put_device(&port->dev); + device_unlock(&parent_port->dev); + } +} + +static resource_size_t find_component_registers(struct device *dev) +{ + struct cxl_register_map map; + struct pci_dev *pdev; + + /* + * Theoretically, CXL component registers can be hosted on a + * non-PCI device, in practice, only cxl_test hits this case. + */ + if (!dev_is_pci(dev)) + return CXL_RESOURCE_NONE; + + pdev = to_pci_dev(dev); + + cxl_find_regblock(pdev, CXL_REGLOC_RBI_COMPONENT, &map); + return cxl_regmap_to_base(pdev, &map); +} + +static int add_port_attach_ep(struct cxl_memdev *cxlmd, + struct device *uport_dev, + struct device *dport_dev) +{ + struct device *dparent = grandparent(dport_dev); + struct cxl_port *port, *parent_port = NULL; + struct cxl_dport *dport, *parent_dport; + resource_size_t component_reg_phys; + int rc; + + if (!dparent) { + /* + * The iteration reached the topology root without finding the + * CXL-root 'cxl_port' on a previous iteration, fail for now to + * be re-probed after platform driver attaches. + */ + dev_dbg(&cxlmd->dev, "%s is a root dport\n", + dev_name(dport_dev)); + return -ENXIO; + } + + parent_port = find_cxl_port(dparent, &parent_dport); + if (!parent_port) { + /* iterate to create this parent_port */ + return -EAGAIN; + } + + device_lock(&parent_port->dev); + if (!parent_port->dev.driver) { + dev_warn(&cxlmd->dev, + "port %s:%s disabled, failed to enumerate CXL.mem\n", + dev_name(&parent_port->dev), dev_name(uport_dev)); + port = ERR_PTR(-ENXIO); + goto out; + } + + port = find_cxl_port_at(parent_port, dport_dev, &dport); + if (!port) { + component_reg_phys = find_component_registers(uport_dev); + port = devm_cxl_add_port(&parent_port->dev, uport_dev, + component_reg_phys, parent_dport); + /* retry find to pick up the new dport information */ + if (!IS_ERR(port)) + port = find_cxl_port_at(parent_port, dport_dev, &dport); + } +out: + device_unlock(&parent_port->dev); + + if (IS_ERR(port)) + rc = PTR_ERR(port); + else { + dev_dbg(&cxlmd->dev, "add to new port %s:%s\n", + dev_name(&port->dev), dev_name(port->uport)); + rc = cxl_add_ep(dport, &cxlmd->dev); + if (rc == -EBUSY) { + /* + * "can't" happen, but this error code means + * something to the caller, so translate it. + */ + rc = -ENXIO; + } + put_device(&port->dev); + } + + put_device(&parent_port->dev); + return rc; +} + +int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd) +{ + struct device *dev = &cxlmd->dev; + struct device *iter; + int rc; + + rc = devm_add_action_or_reset(&cxlmd->dev, cxl_detach_ep, cxlmd); + if (rc) + return rc; + + /* + * Scan for and add all cxl_ports in this device's ancestry. + * Repeat until no more ports are added. Abort if a port add + * attempt fails. + */ +retry: + for (iter = dev; iter; iter = grandparent(iter)) { + struct device *dport_dev = grandparent(iter); + struct device *uport_dev; + struct cxl_dport *dport; + struct cxl_port *port; + + if (!dport_dev) + return 0; + + uport_dev = dport_dev->parent; + if (!uport_dev) { + dev_warn(dev, "at %s no parent for dport: %s\n", + dev_name(iter), dev_name(dport_dev)); + return -ENXIO; + } + + dev_dbg(dev, "scan: iter: %s dport_dev: %s parent: %s\n", + dev_name(iter), dev_name(dport_dev), + dev_name(uport_dev)); + port = find_cxl_port(dport_dev, &dport); + if (port) { + dev_dbg(&cxlmd->dev, + "found already registered port %s:%s\n", + dev_name(&port->dev), dev_name(port->uport)); + rc = cxl_add_ep(dport, &cxlmd->dev); + + /* + * If the endpoint already exists in the port's list, + * that's ok, it was added on a previous pass. + * Otherwise, retry in add_port_attach_ep() after taking + * the parent_port lock as the current port may be being + * reaped. + */ + if (rc && rc != -EBUSY) { + put_device(&port->dev); + return rc; + } + + /* Any more ports to add between this one and the root? */ + if (!dev_is_cxl_root_child(&port->dev)) { + put_device(&port->dev); + continue; + } + + put_device(&port->dev); + return 0; + } + + rc = add_port_attach_ep(cxlmd, uport_dev, dport_dev); + /* port missing, try to add parent */ + if (rc == -EAGAIN) + continue; + /* failed to add ep or port */ + if (rc) + return rc; + /* port added, new descendants possible, start over */ + goto retry; + } + + return 0; +} +EXPORT_SYMBOL_NS_GPL(devm_cxl_enumerate_ports, CXL); + +struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd, + struct cxl_dport **dport) +{ + return find_cxl_port(grandparent(&cxlmd->dev), dport); +} +EXPORT_SYMBOL_NS_GPL(cxl_mem_find_port, CXL); + +static int decoder_populate_targets(struct cxl_switch_decoder *cxlsd, + struct cxl_port *port, int *target_map) +{ + int i, rc = 0; + + if (!target_map) + return 0; + + device_lock_assert(&port->dev); + + if (xa_empty(&port->dports)) + return -EINVAL; + + write_seqlock(&cxlsd->target_lock); + for (i = 0; i < cxlsd->cxld.interleave_ways; i++) { + struct cxl_dport *dport = find_dport(port, target_map[i]); + + if (!dport) { + rc = -ENXIO; + break; + } + cxlsd->target[i] = dport; + } + write_sequnlock(&cxlsd->target_lock); + + return rc; +} + +static struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos) +{ + struct cxl_switch_decoder *cxlsd = &cxlrd->cxlsd; + struct cxl_decoder *cxld = &cxlsd->cxld; + int iw; + + iw = cxld->interleave_ways; + if (dev_WARN_ONCE(&cxld->dev, iw != cxlsd->nr_targets, + "misconfigured root decoder\n")) + return NULL; + + return cxlrd->cxlsd.target[pos % iw]; +} + +static struct lock_class_key cxl_decoder_key; + +/** + * cxl_decoder_init - Common decoder setup / initialization + * @port: owning port of this decoder + * @cxld: common decoder properties to initialize + * + * A port may contain one or more decoders. Each of those decoders + * enable some address space for CXL.mem utilization. A decoder is + * expected to be configured by the caller before registering via + * cxl_decoder_add() + */ +static int cxl_decoder_init(struct cxl_port *port, struct cxl_decoder *cxld) +{ + struct device *dev; + int rc; + + rc = ida_alloc(&port->decoder_ida, GFP_KERNEL); + if (rc < 0) + return rc; + + /* need parent to stick around to release the id */ + get_device(&port->dev); + cxld->id = rc; + + dev = &cxld->dev; + device_initialize(dev); + lockdep_set_class(&dev->mutex, &cxl_decoder_key); + device_set_pm_not_required(dev); + dev->parent = &port->dev; + dev->bus = &cxl_bus_type; + + /* Pre initialize an "empty" decoder */ + cxld->interleave_ways = 1; + cxld->interleave_granularity = PAGE_SIZE; + cxld->target_type = CXL_DECODER_EXPANDER; + cxld->hpa_range = (struct range) { + .start = 0, + .end = -1, + }; + + return 0; +} + +static int cxl_switch_decoder_init(struct cxl_port *port, + struct cxl_switch_decoder *cxlsd, + int nr_targets) +{ + if (nr_targets > CXL_DECODER_MAX_INTERLEAVE) + return -EINVAL; + + cxlsd->nr_targets = nr_targets; + seqlock_init(&cxlsd->target_lock); + return cxl_decoder_init(port, &cxlsd->cxld); +} + +/** + * cxl_root_decoder_alloc - Allocate a root level decoder + * @port: owning CXL root of this decoder + * @nr_targets: static number of downstream targets + * + * Return: A new cxl decoder to be registered by cxl_decoder_add(). A + * 'CXL root' decoder is one that decodes from a top-level / static platform + * firmware description of CXL resources into a CXL standard decode + * topology. + */ +struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port, + unsigned int nr_targets) +{ + struct cxl_root_decoder *cxlrd; + struct cxl_switch_decoder *cxlsd; + struct cxl_decoder *cxld; + int rc; + + if (!is_cxl_root(port)) + return ERR_PTR(-EINVAL); + + cxlrd = kzalloc(struct_size(cxlrd, cxlsd.target, nr_targets), + GFP_KERNEL); + if (!cxlrd) + return ERR_PTR(-ENOMEM); + + cxlsd = &cxlrd->cxlsd; + rc = cxl_switch_decoder_init(port, cxlsd, nr_targets); + if (rc) { + kfree(cxlrd); + return ERR_PTR(rc); + } + + cxlrd->calc_hb = cxl_hb_modulo; + + cxld = &cxlsd->cxld; + cxld->dev.type = &cxl_decoder_root_type; + /* + * cxl_root_decoder_release() special cases negative ids to + * detect memregion_alloc() failures. + */ + atomic_set(&cxlrd->region_id, -1); + rc = memregion_alloc(GFP_KERNEL); + if (rc < 0) { + put_device(&cxld->dev); + return ERR_PTR(rc); + } + + atomic_set(&cxlrd->region_id, rc); + return cxlrd; +} +EXPORT_SYMBOL_NS_GPL(cxl_root_decoder_alloc, CXL); + +/** + * cxl_switch_decoder_alloc - Allocate a switch level decoder + * @port: owning CXL switch port of this decoder + * @nr_targets: max number of dynamically addressable downstream targets + * + * Return: A new cxl decoder to be registered by cxl_decoder_add(). A + * 'switch' decoder is any decoder that can be enumerated by PCIe + * topology and the HDM Decoder Capability. This includes the decoders + * that sit between Switch Upstream Ports / Switch Downstream Ports and + * Host Bridges / Root Ports. + */ +struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port, + unsigned int nr_targets) +{ + struct cxl_switch_decoder *cxlsd; + struct cxl_decoder *cxld; + int rc; + + if (is_cxl_root(port) || is_cxl_endpoint(port)) + return ERR_PTR(-EINVAL); + + cxlsd = kzalloc(struct_size(cxlsd, target, nr_targets), GFP_KERNEL); + if (!cxlsd) + return ERR_PTR(-ENOMEM); + + rc = cxl_switch_decoder_init(port, cxlsd, nr_targets); + if (rc) { + kfree(cxlsd); + return ERR_PTR(rc); + } + + cxld = &cxlsd->cxld; + cxld->dev.type = &cxl_decoder_switch_type; + return cxlsd; +} +EXPORT_SYMBOL_NS_GPL(cxl_switch_decoder_alloc, CXL); + +/** + * cxl_endpoint_decoder_alloc - Allocate an endpoint decoder + * @port: owning port of this decoder + * + * Return: A new cxl decoder to be registered by cxl_decoder_add() + */ +struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port) +{ + struct cxl_endpoint_decoder *cxled; + struct cxl_decoder *cxld; + int rc; + + if (!is_cxl_endpoint(port)) + return ERR_PTR(-EINVAL); + + cxled = kzalloc(sizeof(*cxled), GFP_KERNEL); + if (!cxled) + return ERR_PTR(-ENOMEM); + + cxled->pos = -1; + cxld = &cxled->cxld; + rc = cxl_decoder_init(port, cxld); + if (rc) { + kfree(cxled); + return ERR_PTR(rc); + } + + cxld->dev.type = &cxl_decoder_endpoint_type; + return cxled; +} +EXPORT_SYMBOL_NS_GPL(cxl_endpoint_decoder_alloc, CXL); + +/** + * cxl_decoder_add_locked - Add a decoder with targets + * @cxld: The cxl decoder allocated by cxl_<type>_decoder_alloc() + * @target_map: A list of downstream ports that this decoder can direct memory + * traffic to. These numbers should correspond with the port number + * in the PCIe Link Capabilities structure. + * + * Certain types of decoders may not have any targets. The main example of this + * is an endpoint device. A more awkward example is a hostbridge whose root + * ports get hot added (technically possible, though unlikely). + * + * This is the locked variant of cxl_decoder_add(). + * + * Context: Process context. Expects the device lock of the port that owns the + * @cxld to be held. + * + * Return: Negative error code if the decoder wasn't properly configured; else + * returns 0. + */ +int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map) +{ + struct cxl_port *port; + struct device *dev; + int rc; + + if (WARN_ON_ONCE(!cxld)) + return -EINVAL; + + if (WARN_ON_ONCE(IS_ERR(cxld))) + return PTR_ERR(cxld); + + if (cxld->interleave_ways < 1) + return -EINVAL; + + dev = &cxld->dev; + + port = to_cxl_port(cxld->dev.parent); + if (!is_endpoint_decoder(dev)) { + struct cxl_switch_decoder *cxlsd = to_cxl_switch_decoder(dev); + + rc = decoder_populate_targets(cxlsd, port, target_map); + if (rc && (cxld->flags & CXL_DECODER_F_ENABLE)) { + dev_err(&port->dev, + "Failed to populate active decoder targets\n"); + return rc; + } + } + + rc = dev_set_name(dev, "decoder%d.%d", port->id, cxld->id); + if (rc) + return rc; + + return device_add(dev); +} +EXPORT_SYMBOL_NS_GPL(cxl_decoder_add_locked, CXL); + +/** + * cxl_decoder_add - Add a decoder with targets + * @cxld: The cxl decoder allocated by cxl_<type>_decoder_alloc() + * @target_map: A list of downstream ports that this decoder can direct memory + * traffic to. These numbers should correspond with the port number + * in the PCIe Link Capabilities structure. + * + * This is the unlocked variant of cxl_decoder_add_locked(). + * See cxl_decoder_add_locked(). + * + * Context: Process context. Takes and releases the device lock of the port that + * owns the @cxld. + */ +int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map) +{ + struct cxl_port *port; + int rc; + + if (WARN_ON_ONCE(!cxld)) + return -EINVAL; + + if (WARN_ON_ONCE(IS_ERR(cxld))) + return PTR_ERR(cxld); + + port = to_cxl_port(cxld->dev.parent); + + device_lock(&port->dev); + rc = cxl_decoder_add_locked(cxld, target_map); + device_unlock(&port->dev); + + return rc; +} +EXPORT_SYMBOL_NS_GPL(cxl_decoder_add, CXL); + +static void cxld_unregister(void *dev) +{ + struct cxl_endpoint_decoder *cxled; + + if (is_endpoint_decoder(dev)) { + cxled = to_cxl_endpoint_decoder(dev); + cxl_decoder_kill_region(cxled); + } + + device_unregister(dev); +} + +int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld) +{ + return devm_add_action_or_reset(host, cxld_unregister, &cxld->dev); +} +EXPORT_SYMBOL_NS_GPL(cxl_decoder_autoremove, CXL); + +/** + * __cxl_driver_register - register a driver for the cxl bus + * @cxl_drv: cxl driver structure to attach + * @owner: owning module/driver + * @modname: KBUILD_MODNAME for parent driver + */ +int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner, + const char *modname) +{ + if (!cxl_drv->probe) { + pr_debug("%s ->probe() must be specified\n", modname); + return -EINVAL; + } + + if (!cxl_drv->name) { + pr_debug("%s ->name must be specified\n", modname); + return -EINVAL; + } + + if (!cxl_drv->id) { + pr_debug("%s ->id must be specified\n", modname); + return -EINVAL; + } + + cxl_drv->drv.bus = &cxl_bus_type; + cxl_drv->drv.owner = owner; + cxl_drv->drv.mod_name = modname; + cxl_drv->drv.name = cxl_drv->name; + + return driver_register(&cxl_drv->drv); +} +EXPORT_SYMBOL_NS_GPL(__cxl_driver_register, CXL); + +void cxl_driver_unregister(struct cxl_driver *cxl_drv) +{ + driver_unregister(&cxl_drv->drv); +} +EXPORT_SYMBOL_NS_GPL(cxl_driver_unregister, CXL); + +static int cxl_bus_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + return add_uevent_var(env, "MODALIAS=" CXL_MODALIAS_FMT, + cxl_device_id(dev)); +} + +static int cxl_bus_match(struct device *dev, struct device_driver *drv) +{ + return cxl_device_id(dev) == to_cxl_drv(drv)->id; +} + +static int cxl_bus_probe(struct device *dev) +{ + int rc; + + rc = to_cxl_drv(dev->driver)->probe(dev); + dev_dbg(dev, "probe: %d\n", rc); + return rc; +} + +static void cxl_bus_remove(struct device *dev) +{ + struct cxl_driver *cxl_drv = to_cxl_drv(dev->driver); + + if (cxl_drv->remove) + cxl_drv->remove(dev); +} + +static struct workqueue_struct *cxl_bus_wq; + +int cxl_bus_rescan(void) +{ + return bus_rescan_devices(&cxl_bus_type); +} +EXPORT_SYMBOL_NS_GPL(cxl_bus_rescan, CXL); + +bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd) +{ + return queue_work(cxl_bus_wq, &cxlmd->detach_work); +} +EXPORT_SYMBOL_NS_GPL(schedule_cxl_memdev_detach, CXL); + +/* for user tooling to ensure port disable work has completed */ +static ssize_t flush_store(struct bus_type *bus, const char *buf, size_t count) +{ + if (sysfs_streq(buf, "1")) { + flush_workqueue(cxl_bus_wq); + return count; + } + + return -EINVAL; +} + +static BUS_ATTR_WO(flush); + +static struct attribute *cxl_bus_attributes[] = { + &bus_attr_flush.attr, + NULL, +}; + +static struct attribute_group cxl_bus_attribute_group = { + .attrs = cxl_bus_attributes, +}; + +static const struct attribute_group *cxl_bus_attribute_groups[] = { + &cxl_bus_attribute_group, + NULL, +}; + +struct bus_type cxl_bus_type = { + .name = "cxl", + .uevent = cxl_bus_uevent, + .match = cxl_bus_match, + .probe = cxl_bus_probe, + .remove = cxl_bus_remove, + .bus_groups = cxl_bus_attribute_groups, +}; +EXPORT_SYMBOL_NS_GPL(cxl_bus_type, CXL); + +static struct dentry *cxl_debugfs; + +struct dentry *cxl_debugfs_create_dir(const char *dir) +{ + return debugfs_create_dir(dir, cxl_debugfs); +} +EXPORT_SYMBOL_NS_GPL(cxl_debugfs_create_dir, CXL); + +static __init int cxl_core_init(void) +{ + int rc; + + cxl_debugfs = debugfs_create_dir("cxl", NULL); + + cxl_mbox_init(); + + rc = cxl_memdev_init(); + if (rc) + return rc; + + cxl_bus_wq = alloc_ordered_workqueue("cxl_port", 0); + if (!cxl_bus_wq) { + rc = -ENOMEM; + goto err_wq; + } + + rc = bus_register(&cxl_bus_type); + if (rc) + goto err_bus; + + rc = cxl_region_init(); + if (rc) + goto err_region; + + return 0; + +err_region: + bus_unregister(&cxl_bus_type); +err_bus: + destroy_workqueue(cxl_bus_wq); +err_wq: + cxl_memdev_exit(); + return rc; +} + +static void cxl_core_exit(void) +{ + cxl_region_exit(); + bus_unregister(&cxl_bus_type); + destroy_workqueue(cxl_bus_wq); + cxl_memdev_exit(); + debugfs_remove_recursive(cxl_debugfs); +} + +module_init(cxl_core_init); +module_exit(cxl_core_exit); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c new file mode 100644 index 000000000..5b7d848a6 --- /dev/null +++ b/drivers/cxl/core/region.c @@ -0,0 +1,2006 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2022 Intel Corporation. All rights reserved. */ +#include <linux/memregion.h> +#include <linux/genalloc.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/uuid.h> +#include <linux/idr.h> +#include <cxlmem.h> +#include <cxl.h> +#include "core.h" + +/** + * DOC: cxl core region + * + * CXL Regions represent mapped memory capacity in system physical address + * space. Whereas the CXL Root Decoders identify the bounds of potential CXL + * Memory ranges, Regions represent the active mapped capacity by the HDM + * Decoder Capability structures throughout the Host Bridges, Switches, and + * Endpoints in the topology. + * + * Region configuration has ordering constraints. UUID may be set at any time + * but is only visible for persistent regions. + * 1. Interleave granularity + * 2. Interleave size + * 3. Decoder targets + */ + +/* + * All changes to the interleave configuration occur with this lock held + * for write. + */ +static DECLARE_RWSEM(cxl_region_rwsem); + +static struct cxl_region *to_cxl_region(struct device *dev); + +static ssize_t uuid_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + ssize_t rc; + + rc = down_read_interruptible(&cxl_region_rwsem); + if (rc) + return rc; + rc = sysfs_emit(buf, "%pUb\n", &p->uuid); + up_read(&cxl_region_rwsem); + + return rc; +} + +static int is_dup(struct device *match, void *data) +{ + struct cxl_region_params *p; + struct cxl_region *cxlr; + uuid_t *uuid = data; + + if (!is_cxl_region(match)) + return 0; + + lockdep_assert_held(&cxl_region_rwsem); + cxlr = to_cxl_region(match); + p = &cxlr->params; + + if (uuid_equal(&p->uuid, uuid)) { + dev_dbg(match, "already has uuid: %pUb\n", uuid); + return -EBUSY; + } + + return 0; +} + +static ssize_t uuid_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + uuid_t temp; + ssize_t rc; + + if (len != UUID_STRING_LEN + 1) + return -EINVAL; + + rc = uuid_parse(buf, &temp); + if (rc) + return rc; + + if (uuid_is_null(&temp)) + return -EINVAL; + + rc = down_write_killable(&cxl_region_rwsem); + if (rc) + return rc; + + if (uuid_equal(&p->uuid, &temp)) + goto out; + + rc = -EBUSY; + if (p->state >= CXL_CONFIG_ACTIVE) + goto out; + + rc = bus_for_each_dev(&cxl_bus_type, NULL, &temp, is_dup); + if (rc < 0) + goto out; + + uuid_copy(&p->uuid, &temp); +out: + up_write(&cxl_region_rwsem); + + if (rc) + return rc; + return len; +} +static DEVICE_ATTR_RW(uuid); + +static struct cxl_region_ref *cxl_rr_load(struct cxl_port *port, + struct cxl_region *cxlr) +{ + return xa_load(&port->regions, (unsigned long)cxlr); +} + +static int cxl_region_decode_reset(struct cxl_region *cxlr, int count) +{ + struct cxl_region_params *p = &cxlr->params; + int i; + + for (i = count - 1; i >= 0; i--) { + struct cxl_endpoint_decoder *cxled = p->targets[i]; + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_port *iter = cxled_to_port(cxled); + struct cxl_ep *ep; + int rc = 0; + + while (!is_cxl_root(to_cxl_port(iter->dev.parent))) + iter = to_cxl_port(iter->dev.parent); + + for (ep = cxl_ep_load(iter, cxlmd); iter; + iter = ep->next, ep = cxl_ep_load(iter, cxlmd)) { + struct cxl_region_ref *cxl_rr; + struct cxl_decoder *cxld; + + cxl_rr = cxl_rr_load(iter, cxlr); + cxld = cxl_rr->decoder; + if (cxld->reset) + rc = cxld->reset(cxld); + if (rc) + return rc; + } + + rc = cxled->cxld.reset(&cxled->cxld); + if (rc) + return rc; + } + + return 0; +} + +static int cxl_region_decode_commit(struct cxl_region *cxlr) +{ + struct cxl_region_params *p = &cxlr->params; + int i, rc = 0; + + for (i = 0; i < p->nr_targets; i++) { + struct cxl_endpoint_decoder *cxled = p->targets[i]; + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_region_ref *cxl_rr; + struct cxl_decoder *cxld; + struct cxl_port *iter; + struct cxl_ep *ep; + + /* commit bottom up */ + for (iter = cxled_to_port(cxled); !is_cxl_root(iter); + iter = to_cxl_port(iter->dev.parent)) { + cxl_rr = cxl_rr_load(iter, cxlr); + cxld = cxl_rr->decoder; + if (cxld->commit) + rc = cxld->commit(cxld); + if (rc) + break; + } + + if (rc) { + /* programming @iter failed, teardown */ + for (ep = cxl_ep_load(iter, cxlmd); ep && iter; + iter = ep->next, ep = cxl_ep_load(iter, cxlmd)) { + cxl_rr = cxl_rr_load(iter, cxlr); + cxld = cxl_rr->decoder; + if (cxld->reset) + cxld->reset(cxld); + } + + cxled->cxld.reset(&cxled->cxld); + goto err; + } + } + + return 0; + +err: + /* undo the targets that were successfully committed */ + cxl_region_decode_reset(cxlr, i); + return rc; +} + +static ssize_t commit_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + bool commit; + ssize_t rc; + + rc = kstrtobool(buf, &commit); + if (rc) + return rc; + + rc = down_write_killable(&cxl_region_rwsem); + if (rc) + return rc; + + /* Already in the requested state? */ + if (commit && p->state >= CXL_CONFIG_COMMIT) + goto out; + if (!commit && p->state < CXL_CONFIG_COMMIT) + goto out; + + /* Not ready to commit? */ + if (commit && p->state < CXL_CONFIG_ACTIVE) { + rc = -ENXIO; + goto out; + } + + if (commit) + rc = cxl_region_decode_commit(cxlr); + else { + p->state = CXL_CONFIG_RESET_PENDING; + up_write(&cxl_region_rwsem); + device_release_driver(&cxlr->dev); + down_write(&cxl_region_rwsem); + + /* + * The lock was dropped, so need to revalidate that the reset is + * still pending. + */ + if (p->state == CXL_CONFIG_RESET_PENDING) + rc = cxl_region_decode_reset(cxlr, p->interleave_ways); + } + + if (rc) + goto out; + + if (commit) + p->state = CXL_CONFIG_COMMIT; + else if (p->state == CXL_CONFIG_RESET_PENDING) + p->state = CXL_CONFIG_ACTIVE; + +out: + up_write(&cxl_region_rwsem); + + if (rc) + return rc; + return len; +} + +static ssize_t commit_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + ssize_t rc; + + rc = down_read_interruptible(&cxl_region_rwsem); + if (rc) + return rc; + rc = sysfs_emit(buf, "%d\n", p->state >= CXL_CONFIG_COMMIT); + up_read(&cxl_region_rwsem); + + return rc; +} +static DEVICE_ATTR_RW(commit); + +static umode_t cxl_region_visible(struct kobject *kobj, struct attribute *a, + int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct cxl_region *cxlr = to_cxl_region(dev); + + if (a == &dev_attr_uuid.attr && cxlr->mode != CXL_DECODER_PMEM) + return 0; + return a->mode; +} + +static ssize_t interleave_ways_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + ssize_t rc; + + rc = down_read_interruptible(&cxl_region_rwsem); + if (rc) + return rc; + rc = sysfs_emit(buf, "%d\n", p->interleave_ways); + up_read(&cxl_region_rwsem); + + return rc; +} + +static const struct attribute_group *get_cxl_region_target_group(void); + +static ssize_t interleave_ways_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev->parent); + struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld; + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + unsigned int val, save; + int rc; + u8 iw; + + rc = kstrtouint(buf, 0, &val); + if (rc) + return rc; + + rc = ways_to_cxl(val, &iw); + if (rc) + return rc; + + /* + * Even for x3, x6, and x12 interleaves the region interleave must be a + * power of 2 multiple of the host bridge interleave. + */ + if (!is_power_of_2(val / cxld->interleave_ways) || + (val % cxld->interleave_ways)) { + dev_dbg(&cxlr->dev, "invalid interleave: %d\n", val); + return -EINVAL; + } + + rc = down_write_killable(&cxl_region_rwsem); + if (rc) + return rc; + if (p->state >= CXL_CONFIG_INTERLEAVE_ACTIVE) { + rc = -EBUSY; + goto out; + } + + save = p->interleave_ways; + p->interleave_ways = val; + rc = sysfs_update_group(&cxlr->dev.kobj, get_cxl_region_target_group()); + if (rc) + p->interleave_ways = save; +out: + up_write(&cxl_region_rwsem); + if (rc) + return rc; + return len; +} +static DEVICE_ATTR_RW(interleave_ways); + +static ssize_t interleave_granularity_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + ssize_t rc; + + rc = down_read_interruptible(&cxl_region_rwsem); + if (rc) + return rc; + rc = sysfs_emit(buf, "%d\n", p->interleave_granularity); + up_read(&cxl_region_rwsem); + + return rc; +} + +static ssize_t interleave_granularity_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev->parent); + struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld; + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + int rc, val; + u16 ig; + + rc = kstrtoint(buf, 0, &val); + if (rc) + return rc; + + rc = granularity_to_cxl(val, &ig); + if (rc) + return rc; + + /* + * When the host-bridge is interleaved, disallow region granularity != + * root granularity. Regions with a granularity less than the root + * interleave result in needing multiple endpoints to support a single + * slot in the interleave (possible to suport in the future). Regions + * with a granularity greater than the root interleave result in invalid + * DPA translations (invalid to support). + */ + if (cxld->interleave_ways > 1 && val != cxld->interleave_granularity) + return -EINVAL; + + rc = down_write_killable(&cxl_region_rwsem); + if (rc) + return rc; + if (p->state >= CXL_CONFIG_INTERLEAVE_ACTIVE) { + rc = -EBUSY; + goto out; + } + + p->interleave_granularity = val; +out: + up_write(&cxl_region_rwsem); + if (rc) + return rc; + return len; +} +static DEVICE_ATTR_RW(interleave_granularity); + +static ssize_t resource_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + u64 resource = -1ULL; + ssize_t rc; + + rc = down_read_interruptible(&cxl_region_rwsem); + if (rc) + return rc; + if (p->res) + resource = p->res->start; + rc = sysfs_emit(buf, "%#llx\n", resource); + up_read(&cxl_region_rwsem); + + return rc; +} +static DEVICE_ATTR_RO(resource); + +static int alloc_hpa(struct cxl_region *cxlr, resource_size_t size) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent); + struct cxl_region_params *p = &cxlr->params; + struct resource *res; + u64 remainder = 0; + + lockdep_assert_held_write(&cxl_region_rwsem); + + /* Nothing to do... */ + if (p->res && resource_size(p->res) == size) + return 0; + + /* To change size the old size must be freed first */ + if (p->res) + return -EBUSY; + + if (p->state >= CXL_CONFIG_INTERLEAVE_ACTIVE) + return -EBUSY; + + /* ways, granularity and uuid (if PMEM) need to be set before HPA */ + if (!p->interleave_ways || !p->interleave_granularity || + (cxlr->mode == CXL_DECODER_PMEM && uuid_is_null(&p->uuid))) + return -ENXIO; + + div64_u64_rem(size, (u64)SZ_256M * p->interleave_ways, &remainder); + if (remainder) + return -EINVAL; + + res = alloc_free_mem_region(cxlrd->res, size, SZ_256M, + dev_name(&cxlr->dev)); + if (IS_ERR(res)) { + dev_dbg(&cxlr->dev, "failed to allocate HPA: %ld\n", + PTR_ERR(res)); + return PTR_ERR(res); + } + + p->res = res; + p->state = CXL_CONFIG_INTERLEAVE_ACTIVE; + + return 0; +} + +static void cxl_region_iomem_release(struct cxl_region *cxlr) +{ + struct cxl_region_params *p = &cxlr->params; + + if (device_is_registered(&cxlr->dev)) + lockdep_assert_held_write(&cxl_region_rwsem); + if (p->res) { + remove_resource(p->res); + kfree(p->res); + p->res = NULL; + } +} + +static int free_hpa(struct cxl_region *cxlr) +{ + struct cxl_region_params *p = &cxlr->params; + + lockdep_assert_held_write(&cxl_region_rwsem); + + if (!p->res) + return 0; + + if (p->state >= CXL_CONFIG_ACTIVE) + return -EBUSY; + + cxl_region_iomem_release(cxlr); + p->state = CXL_CONFIG_IDLE; + return 0; +} + +static ssize_t size_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + u64 val; + int rc; + + rc = kstrtou64(buf, 0, &val); + if (rc) + return rc; + + rc = down_write_killable(&cxl_region_rwsem); + if (rc) + return rc; + + if (val) + rc = alloc_hpa(cxlr, val); + else + rc = free_hpa(cxlr); + up_write(&cxl_region_rwsem); + + if (rc) + return rc; + + return len; +} + +static ssize_t size_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + u64 size = 0; + ssize_t rc; + + rc = down_read_interruptible(&cxl_region_rwsem); + if (rc) + return rc; + if (p->res) + size = resource_size(p->res); + rc = sysfs_emit(buf, "%#llx\n", size); + up_read(&cxl_region_rwsem); + + return rc; +} +static DEVICE_ATTR_RW(size); + +static struct attribute *cxl_region_attrs[] = { + &dev_attr_uuid.attr, + &dev_attr_commit.attr, + &dev_attr_interleave_ways.attr, + &dev_attr_interleave_granularity.attr, + &dev_attr_resource.attr, + &dev_attr_size.attr, + NULL, +}; + +static const struct attribute_group cxl_region_group = { + .attrs = cxl_region_attrs, + .is_visible = cxl_region_visible, +}; + +static size_t show_targetN(struct cxl_region *cxlr, char *buf, int pos) +{ + struct cxl_region_params *p = &cxlr->params; + struct cxl_endpoint_decoder *cxled; + int rc; + + rc = down_read_interruptible(&cxl_region_rwsem); + if (rc) + return rc; + + if (pos >= p->interleave_ways) { + dev_dbg(&cxlr->dev, "position %d out of range %d\n", pos, + p->interleave_ways); + rc = -ENXIO; + goto out; + } + + cxled = p->targets[pos]; + if (!cxled) + rc = sysfs_emit(buf, "\n"); + else + rc = sysfs_emit(buf, "%s\n", dev_name(&cxled->cxld.dev)); +out: + up_read(&cxl_region_rwsem); + + return rc; +} + +static int match_free_decoder(struct device *dev, void *data) +{ + struct cxl_decoder *cxld; + int *id = data; + + if (!is_switch_decoder(dev)) + return 0; + + cxld = to_cxl_decoder(dev); + + /* enforce ordered allocation */ + if (cxld->id != *id) + return 0; + + if (!cxld->region) + return 1; + + (*id)++; + + return 0; +} + +static struct cxl_decoder *cxl_region_find_decoder(struct cxl_port *port, + struct cxl_region *cxlr) +{ + struct device *dev; + int id = 0; + + dev = device_find_child(&port->dev, &id, match_free_decoder); + if (!dev) + return NULL; + /* + * This decoder is pinned registered as long as the endpoint decoder is + * registered, and endpoint decoder unregistration holds the + * cxl_region_rwsem over unregister events, so no need to hold on to + * this extra reference. + */ + put_device(dev); + return to_cxl_decoder(dev); +} + +static struct cxl_region_ref *alloc_region_ref(struct cxl_port *port, + struct cxl_region *cxlr) +{ + struct cxl_region_params *p = &cxlr->params; + struct cxl_region_ref *cxl_rr, *iter; + unsigned long index; + int rc; + + xa_for_each(&port->regions, index, iter) { + struct cxl_region_params *ip = &iter->region->params; + + if (!ip->res) + continue; + + if (ip->res->start > p->res->start) { + dev_dbg(&cxlr->dev, + "%s: HPA order violation %s:%pr vs %pr\n", + dev_name(&port->dev), + dev_name(&iter->region->dev), ip->res, p->res); + return ERR_PTR(-EBUSY); + } + } + + cxl_rr = kzalloc(sizeof(*cxl_rr), GFP_KERNEL); + if (!cxl_rr) + return ERR_PTR(-ENOMEM); + cxl_rr->port = port; + cxl_rr->region = cxlr; + cxl_rr->nr_targets = 1; + xa_init(&cxl_rr->endpoints); + + rc = xa_insert(&port->regions, (unsigned long)cxlr, cxl_rr, GFP_KERNEL); + if (rc) { + dev_dbg(&cxlr->dev, + "%s: failed to track region reference: %d\n", + dev_name(&port->dev), rc); + kfree(cxl_rr); + return ERR_PTR(rc); + } + + return cxl_rr; +} + +static void cxl_rr_free_decoder(struct cxl_region_ref *cxl_rr) +{ + struct cxl_region *cxlr = cxl_rr->region; + struct cxl_decoder *cxld = cxl_rr->decoder; + + if (!cxld) + return; + + dev_WARN_ONCE(&cxlr->dev, cxld->region != cxlr, "region mismatch\n"); + if (cxld->region == cxlr) { + cxld->region = NULL; + put_device(&cxlr->dev); + } +} + +static void free_region_ref(struct cxl_region_ref *cxl_rr) +{ + struct cxl_port *port = cxl_rr->port; + struct cxl_region *cxlr = cxl_rr->region; + + cxl_rr_free_decoder(cxl_rr); + xa_erase(&port->regions, (unsigned long)cxlr); + xa_destroy(&cxl_rr->endpoints); + kfree(cxl_rr); +} + +static int cxl_rr_ep_add(struct cxl_region_ref *cxl_rr, + struct cxl_endpoint_decoder *cxled) +{ + int rc; + struct cxl_port *port = cxl_rr->port; + struct cxl_region *cxlr = cxl_rr->region; + struct cxl_decoder *cxld = cxl_rr->decoder; + struct cxl_ep *ep = cxl_ep_load(port, cxled_to_memdev(cxled)); + + if (ep) { + rc = xa_insert(&cxl_rr->endpoints, (unsigned long)cxled, ep, + GFP_KERNEL); + if (rc) + return rc; + } + cxl_rr->nr_eps++; + + if (!cxld->region) { + cxld->region = cxlr; + get_device(&cxlr->dev); + } + + return 0; +} + +static int cxl_rr_alloc_decoder(struct cxl_port *port, struct cxl_region *cxlr, + struct cxl_endpoint_decoder *cxled, + struct cxl_region_ref *cxl_rr) +{ + struct cxl_decoder *cxld; + + if (port == cxled_to_port(cxled)) + cxld = &cxled->cxld; + else + cxld = cxl_region_find_decoder(port, cxlr); + if (!cxld) { + dev_dbg(&cxlr->dev, "%s: no decoder available\n", + dev_name(&port->dev)); + return -EBUSY; + } + + if (cxld->region) { + dev_dbg(&cxlr->dev, "%s: %s already attached to %s\n", + dev_name(&port->dev), dev_name(&cxld->dev), + dev_name(&cxld->region->dev)); + return -EBUSY; + } + + cxl_rr->decoder = cxld; + return 0; +} + +/** + * cxl_port_attach_region() - track a region's interest in a port by endpoint + * @port: port to add a new region reference 'struct cxl_region_ref' + * @cxlr: region to attach to @port + * @cxled: endpoint decoder used to create or further pin a region reference + * @pos: interleave position of @cxled in @cxlr + * + * The attach event is an opportunity to validate CXL decode setup + * constraints and record metadata needed for programming HDM decoders, + * in particular decoder target lists. + * + * The steps are: + * + * - validate that there are no other regions with a higher HPA already + * associated with @port + * - establish a region reference if one is not already present + * + * - additionally allocate a decoder instance that will host @cxlr on + * @port + * + * - pin the region reference by the endpoint + * - account for how many entries in @port's target list are needed to + * cover all of the added endpoints. + */ +static int cxl_port_attach_region(struct cxl_port *port, + struct cxl_region *cxlr, + struct cxl_endpoint_decoder *cxled, int pos) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_ep *ep = cxl_ep_load(port, cxlmd); + struct cxl_region_ref *cxl_rr; + bool nr_targets_inc = false; + struct cxl_decoder *cxld; + unsigned long index; + int rc = -EBUSY; + + lockdep_assert_held_write(&cxl_region_rwsem); + + cxl_rr = cxl_rr_load(port, cxlr); + if (cxl_rr) { + struct cxl_ep *ep_iter; + int found = 0; + + /* + * Walk the existing endpoints that have been attached to + * @cxlr at @port and see if they share the same 'next' port + * in the downstream direction. I.e. endpoints that share common + * upstream switch. + */ + xa_for_each(&cxl_rr->endpoints, index, ep_iter) { + if (ep_iter == ep) + continue; + if (ep_iter->next == ep->next) { + found++; + break; + } + } + + /* + * New target port, or @port is an endpoint port that always + * accounts its own local decode as a target. + */ + if (!found || !ep->next) { + cxl_rr->nr_targets++; + nr_targets_inc = true; + } + } else { + cxl_rr = alloc_region_ref(port, cxlr); + if (IS_ERR(cxl_rr)) { + dev_dbg(&cxlr->dev, + "%s: failed to allocate region reference\n", + dev_name(&port->dev)); + return PTR_ERR(cxl_rr); + } + nr_targets_inc = true; + + rc = cxl_rr_alloc_decoder(port, cxlr, cxled, cxl_rr); + if (rc) + goto out_erase; + } + cxld = cxl_rr->decoder; + + rc = cxl_rr_ep_add(cxl_rr, cxled); + if (rc) { + dev_dbg(&cxlr->dev, + "%s: failed to track endpoint %s:%s reference\n", + dev_name(&port->dev), dev_name(&cxlmd->dev), + dev_name(&cxld->dev)); + goto out_erase; + } + + dev_dbg(&cxlr->dev, + "%s:%s %s add: %s:%s @ %d next: %s nr_eps: %d nr_targets: %d\n", + dev_name(port->uport), dev_name(&port->dev), + dev_name(&cxld->dev), dev_name(&cxlmd->dev), + dev_name(&cxled->cxld.dev), pos, + ep ? ep->next ? dev_name(ep->next->uport) : + dev_name(&cxlmd->dev) : + "none", + cxl_rr->nr_eps, cxl_rr->nr_targets); + + return 0; +out_erase: + if (nr_targets_inc) + cxl_rr->nr_targets--; + if (cxl_rr->nr_eps == 0) + free_region_ref(cxl_rr); + return rc; +} + +static void cxl_port_detach_region(struct cxl_port *port, + struct cxl_region *cxlr, + struct cxl_endpoint_decoder *cxled) +{ + struct cxl_region_ref *cxl_rr; + struct cxl_ep *ep = NULL; + + lockdep_assert_held_write(&cxl_region_rwsem); + + cxl_rr = cxl_rr_load(port, cxlr); + if (!cxl_rr) + return; + + /* + * Endpoint ports do not carry cxl_ep references, and they + * never target more than one endpoint by definition + */ + if (cxl_rr->decoder == &cxled->cxld) + cxl_rr->nr_eps--; + else + ep = xa_erase(&cxl_rr->endpoints, (unsigned long)cxled); + if (ep) { + struct cxl_ep *ep_iter; + unsigned long index; + int found = 0; + + cxl_rr->nr_eps--; + xa_for_each(&cxl_rr->endpoints, index, ep_iter) { + if (ep_iter->next == ep->next) { + found++; + break; + } + } + if (!found) + cxl_rr->nr_targets--; + } + + if (cxl_rr->nr_eps == 0) + free_region_ref(cxl_rr); +} + +static int check_last_peer(struct cxl_endpoint_decoder *cxled, + struct cxl_ep *ep, struct cxl_region_ref *cxl_rr, + int distance) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_region *cxlr = cxl_rr->region; + struct cxl_region_params *p = &cxlr->params; + struct cxl_endpoint_decoder *cxled_peer; + struct cxl_port *port = cxl_rr->port; + struct cxl_memdev *cxlmd_peer; + struct cxl_ep *ep_peer; + int pos = cxled->pos; + + /* + * If this position wants to share a dport with the last endpoint mapped + * then that endpoint, at index 'position - distance', must also be + * mapped by this dport. + */ + if (pos < distance) { + dev_dbg(&cxlr->dev, "%s:%s: cannot host %s:%s at %d\n", + dev_name(port->uport), dev_name(&port->dev), + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), pos); + return -ENXIO; + } + cxled_peer = p->targets[pos - distance]; + cxlmd_peer = cxled_to_memdev(cxled_peer); + ep_peer = cxl_ep_load(port, cxlmd_peer); + if (ep->dport != ep_peer->dport) { + dev_dbg(&cxlr->dev, + "%s:%s: %s:%s pos %d mismatched peer %s:%s\n", + dev_name(port->uport), dev_name(&port->dev), + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), pos, + dev_name(&cxlmd_peer->dev), + dev_name(&cxled_peer->cxld.dev)); + return -ENXIO; + } + + return 0; +} + +static int cxl_port_setup_targets(struct cxl_port *port, + struct cxl_region *cxlr, + struct cxl_endpoint_decoder *cxled) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent); + int parent_iw, parent_ig, ig, iw, rc, inc = 0, pos = cxled->pos; + struct cxl_port *parent_port = to_cxl_port(port->dev.parent); + struct cxl_region_ref *cxl_rr = cxl_rr_load(port, cxlr); + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_ep *ep = cxl_ep_load(port, cxlmd); + struct cxl_region_params *p = &cxlr->params; + struct cxl_decoder *cxld = cxl_rr->decoder; + struct cxl_switch_decoder *cxlsd; + u16 eig, peig; + u8 eiw, peiw; + + /* + * While root level decoders support x3, x6, x12, switch level + * decoders only support powers of 2 up to x16. + */ + if (!is_power_of_2(cxl_rr->nr_targets)) { + dev_dbg(&cxlr->dev, "%s:%s: invalid target count %d\n", + dev_name(port->uport), dev_name(&port->dev), + cxl_rr->nr_targets); + return -EINVAL; + } + + cxlsd = to_cxl_switch_decoder(&cxld->dev); + if (cxl_rr->nr_targets_set) { + int i, distance; + + /* + * Passthrough decoders impose no distance requirements between + * peers + */ + if (cxl_rr->nr_targets == 1) + distance = 0; + else + distance = p->nr_targets / cxl_rr->nr_targets; + for (i = 0; i < cxl_rr->nr_targets_set; i++) + if (ep->dport == cxlsd->target[i]) { + rc = check_last_peer(cxled, ep, cxl_rr, + distance); + if (rc) + return rc; + goto out_target_set; + } + goto add_target; + } + + if (is_cxl_root(parent_port)) { + /* + * Root decoder IG is always set to value in CFMWS which + * may be different than this region's IG. We can use the + * region's IG here since interleave_granularity_store() + * does not allow interleaved host-bridges with + * root IG != region IG. + */ + parent_ig = p->interleave_granularity; + parent_iw = cxlrd->cxlsd.cxld.interleave_ways; + /* + * For purposes of address bit routing, use power-of-2 math for + * switch ports. + */ + if (!is_power_of_2(parent_iw)) + parent_iw /= 3; + } else { + struct cxl_region_ref *parent_rr; + struct cxl_decoder *parent_cxld; + + parent_rr = cxl_rr_load(parent_port, cxlr); + parent_cxld = parent_rr->decoder; + parent_ig = parent_cxld->interleave_granularity; + parent_iw = parent_cxld->interleave_ways; + } + + rc = granularity_to_cxl(parent_ig, &peig); + if (rc) { + dev_dbg(&cxlr->dev, "%s:%s: invalid parent granularity: %d\n", + dev_name(parent_port->uport), + dev_name(&parent_port->dev), parent_ig); + return rc; + } + + rc = ways_to_cxl(parent_iw, &peiw); + if (rc) { + dev_dbg(&cxlr->dev, "%s:%s: invalid parent interleave: %d\n", + dev_name(parent_port->uport), + dev_name(&parent_port->dev), parent_iw); + return rc; + } + + iw = cxl_rr->nr_targets; + rc = ways_to_cxl(iw, &eiw); + if (rc) { + dev_dbg(&cxlr->dev, "%s:%s: invalid port interleave: %d\n", + dev_name(port->uport), dev_name(&port->dev), iw); + return rc; + } + + /* + * If @parent_port is masking address bits, pick the next unused address + * bit to route @port's targets. + */ + if (parent_iw > 1 && cxl_rr->nr_targets > 1) { + u32 address_bit = max(peig + peiw, eiw + peig); + + eig = address_bit - eiw + 1; + } else { + eiw = peiw; + eig = peig; + } + + rc = cxl_to_granularity(eig, &ig); + if (rc) { + dev_dbg(&cxlr->dev, "%s:%s: invalid interleave: %d\n", + dev_name(port->uport), dev_name(&port->dev), + 256 << eig); + return rc; + } + + cxld->interleave_ways = iw; + cxld->interleave_granularity = ig; + cxld->hpa_range = (struct range) { + .start = p->res->start, + .end = p->res->end, + }; + dev_dbg(&cxlr->dev, "%s:%s iw: %d ig: %d\n", dev_name(port->uport), + dev_name(&port->dev), iw, ig); +add_target: + if (cxl_rr->nr_targets_set == cxl_rr->nr_targets) { + dev_dbg(&cxlr->dev, + "%s:%s: targets full trying to add %s:%s at %d\n", + dev_name(port->uport), dev_name(&port->dev), + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), pos); + return -ENXIO; + } + cxlsd->target[cxl_rr->nr_targets_set] = ep->dport; + inc = 1; +out_target_set: + cxl_rr->nr_targets_set += inc; + dev_dbg(&cxlr->dev, "%s:%s target[%d] = %s for %s:%s @ %d\n", + dev_name(port->uport), dev_name(&port->dev), + cxl_rr->nr_targets_set - 1, dev_name(ep->dport->dport), + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), pos); + + return 0; +} + +static void cxl_port_reset_targets(struct cxl_port *port, + struct cxl_region *cxlr) +{ + struct cxl_region_ref *cxl_rr = cxl_rr_load(port, cxlr); + struct cxl_decoder *cxld; + + /* + * After the last endpoint has been detached the entire cxl_rr may now + * be gone. + */ + if (!cxl_rr) + return; + cxl_rr->nr_targets_set = 0; + + cxld = cxl_rr->decoder; + cxld->hpa_range = (struct range) { + .start = 0, + .end = -1, + }; +} + +static void cxl_region_teardown_targets(struct cxl_region *cxlr) +{ + struct cxl_region_params *p = &cxlr->params; + struct cxl_endpoint_decoder *cxled; + struct cxl_memdev *cxlmd; + struct cxl_port *iter; + struct cxl_ep *ep; + int i; + + for (i = 0; i < p->nr_targets; i++) { + cxled = p->targets[i]; + cxlmd = cxled_to_memdev(cxled); + + iter = cxled_to_port(cxled); + while (!is_cxl_root(to_cxl_port(iter->dev.parent))) + iter = to_cxl_port(iter->dev.parent); + + for (ep = cxl_ep_load(iter, cxlmd); iter; + iter = ep->next, ep = cxl_ep_load(iter, cxlmd)) + cxl_port_reset_targets(iter, cxlr); + } +} + +static int cxl_region_setup_targets(struct cxl_region *cxlr) +{ + struct cxl_region_params *p = &cxlr->params; + struct cxl_endpoint_decoder *cxled; + struct cxl_memdev *cxlmd; + struct cxl_port *iter; + struct cxl_ep *ep; + int i, rc; + + for (i = 0; i < p->nr_targets; i++) { + cxled = p->targets[i]; + cxlmd = cxled_to_memdev(cxled); + + iter = cxled_to_port(cxled); + while (!is_cxl_root(to_cxl_port(iter->dev.parent))) + iter = to_cxl_port(iter->dev.parent); + + /* + * Descend the topology tree programming targets while + * looking for conflicts. + */ + for (ep = cxl_ep_load(iter, cxlmd); iter; + iter = ep->next, ep = cxl_ep_load(iter, cxlmd)) { + rc = cxl_port_setup_targets(iter, cxlr, cxled); + if (rc) { + cxl_region_teardown_targets(cxlr); + return rc; + } + } + } + + return 0; +} + +static int cxl_region_validate_position(struct cxl_region *cxlr, + struct cxl_endpoint_decoder *cxled, + int pos) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_region_params *p = &cxlr->params; + int i; + + if (pos < 0 || pos >= p->interleave_ways) { + dev_dbg(&cxlr->dev, "position %d out of range %d\n", pos, + p->interleave_ways); + return -ENXIO; + } + + if (p->targets[pos] == cxled) + return 0; + + if (p->targets[pos]) { + struct cxl_endpoint_decoder *cxled_target = p->targets[pos]; + struct cxl_memdev *cxlmd_target = cxled_to_memdev(cxled_target); + + dev_dbg(&cxlr->dev, "position %d already assigned to %s:%s\n", + pos, dev_name(&cxlmd_target->dev), + dev_name(&cxled_target->cxld.dev)); + return -EBUSY; + } + + for (i = 0; i < p->interleave_ways; i++) { + struct cxl_endpoint_decoder *cxled_target; + struct cxl_memdev *cxlmd_target; + + cxled_target = p->targets[i]; + if (!cxled_target) + continue; + + cxlmd_target = cxled_to_memdev(cxled_target); + if (cxlmd_target == cxlmd) { + dev_dbg(&cxlr->dev, + "%s already specified at position %d via: %s\n", + dev_name(&cxlmd->dev), pos, + dev_name(&cxled_target->cxld.dev)); + return -EBUSY; + } + } + + return 0; +} + +static int cxl_region_attach_position(struct cxl_region *cxlr, + struct cxl_root_decoder *cxlrd, + struct cxl_endpoint_decoder *cxled, + const struct cxl_dport *dport, int pos) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_port *iter; + int rc; + + if (cxlrd->calc_hb(cxlrd, pos) != dport) { + dev_dbg(&cxlr->dev, "%s:%s invalid target position for %s\n", + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), + dev_name(&cxlrd->cxlsd.cxld.dev)); + return -ENXIO; + } + + for (iter = cxled_to_port(cxled); !is_cxl_root(iter); + iter = to_cxl_port(iter->dev.parent)) { + rc = cxl_port_attach_region(iter, cxlr, cxled, pos); + if (rc) + goto err; + } + + return 0; + +err: + for (iter = cxled_to_port(cxled); !is_cxl_root(iter); + iter = to_cxl_port(iter->dev.parent)) + cxl_port_detach_region(iter, cxlr, cxled); + return rc; +} + +static int cxl_region_attach(struct cxl_region *cxlr, + struct cxl_endpoint_decoder *cxled, int pos) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(cxlr->dev.parent); + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_region_params *p = &cxlr->params; + struct cxl_port *ep_port, *root_port; + struct cxl_dport *dport; + int rc = -ENXIO; + + if (cxled->mode != cxlr->mode) { + dev_dbg(&cxlr->dev, "%s region mode: %d mismatch: %d\n", + dev_name(&cxled->cxld.dev), cxlr->mode, cxled->mode); + return -EINVAL; + } + + if (cxled->mode == CXL_DECODER_DEAD) { + dev_dbg(&cxlr->dev, "%s dead\n", dev_name(&cxled->cxld.dev)); + return -ENODEV; + } + + /* all full of members, or interleave config not established? */ + if (p->state > CXL_CONFIG_INTERLEAVE_ACTIVE) { + dev_dbg(&cxlr->dev, "region already active\n"); + return -EBUSY; + } else if (p->state < CXL_CONFIG_INTERLEAVE_ACTIVE) { + dev_dbg(&cxlr->dev, "interleave config missing\n"); + return -ENXIO; + } + + if (p->nr_targets >= p->interleave_ways) { + dev_dbg(&cxlr->dev, "region already has %d endpoints\n", + p->nr_targets); + return -EINVAL; + } + + ep_port = cxled_to_port(cxled); + root_port = cxlrd_to_port(cxlrd); + dport = cxl_find_dport_by_dev(root_port, ep_port->host_bridge); + if (!dport) { + dev_dbg(&cxlr->dev, "%s:%s invalid target for %s\n", + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), + dev_name(cxlr->dev.parent)); + return -ENXIO; + } + + if (cxled->cxld.target_type != cxlr->type) { + dev_dbg(&cxlr->dev, "%s:%s type mismatch: %d vs %d\n", + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), + cxled->cxld.target_type, cxlr->type); + return -ENXIO; + } + + if (!cxled->dpa_res) { + dev_dbg(&cxlr->dev, "%s:%s: missing DPA allocation.\n", + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev)); + return -ENXIO; + } + + if (resource_size(cxled->dpa_res) * p->interleave_ways != + resource_size(p->res)) { + dev_dbg(&cxlr->dev, + "%s:%s: decoder-size-%#llx * ways-%d != region-size-%#llx\n", + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), + (u64)resource_size(cxled->dpa_res), p->interleave_ways, + (u64)resource_size(p->res)); + return -EINVAL; + } + + rc = cxl_region_validate_position(cxlr, cxled, pos); + if (rc) + return rc; + + rc = cxl_region_attach_position(cxlr, cxlrd, cxled, dport, pos); + if (rc) + return rc; + + p->targets[pos] = cxled; + cxled->pos = pos; + p->nr_targets++; + + if (p->nr_targets == p->interleave_ways) { + rc = cxl_region_setup_targets(cxlr); + if (rc) + return rc; + p->state = CXL_CONFIG_ACTIVE; + } + + cxled->cxld.interleave_ways = p->interleave_ways; + cxled->cxld.interleave_granularity = p->interleave_granularity; + cxled->cxld.hpa_range = (struct range) { + .start = p->res->start, + .end = p->res->end, + }; + + return 0; +} + +static int cxl_region_detach(struct cxl_endpoint_decoder *cxled) +{ + struct cxl_port *iter, *ep_port = cxled_to_port(cxled); + struct cxl_region *cxlr = cxled->cxld.region; + struct cxl_region_params *p; + int rc = 0; + + lockdep_assert_held_write(&cxl_region_rwsem); + + if (!cxlr) + return 0; + + p = &cxlr->params; + get_device(&cxlr->dev); + + if (p->state > CXL_CONFIG_ACTIVE) { + /* + * TODO: tear down all impacted regions if a device is + * removed out of order + */ + rc = cxl_region_decode_reset(cxlr, p->interleave_ways); + if (rc) + goto out; + p->state = CXL_CONFIG_ACTIVE; + } + + for (iter = ep_port; !is_cxl_root(iter); + iter = to_cxl_port(iter->dev.parent)) + cxl_port_detach_region(iter, cxlr, cxled); + + if (cxled->pos < 0 || cxled->pos >= p->interleave_ways || + p->targets[cxled->pos] != cxled) { + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + + dev_WARN_ONCE(&cxlr->dev, 1, "expected %s:%s at position %d\n", + dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), + cxled->pos); + goto out; + } + + if (p->state == CXL_CONFIG_ACTIVE) { + p->state = CXL_CONFIG_INTERLEAVE_ACTIVE; + cxl_region_teardown_targets(cxlr); + } + p->targets[cxled->pos] = NULL; + p->nr_targets--; + cxled->cxld.hpa_range = (struct range) { + .start = 0, + .end = -1, + }; + + /* notify the region driver that one of its targets has departed */ + up_write(&cxl_region_rwsem); + device_release_driver(&cxlr->dev); + down_write(&cxl_region_rwsem); +out: + put_device(&cxlr->dev); + return rc; +} + +void cxl_decoder_kill_region(struct cxl_endpoint_decoder *cxled) +{ + down_write(&cxl_region_rwsem); + cxled->mode = CXL_DECODER_DEAD; + cxl_region_detach(cxled); + up_write(&cxl_region_rwsem); +} + +static int attach_target(struct cxl_region *cxlr, const char *decoder, int pos) +{ + struct device *dev; + int rc; + + dev = bus_find_device_by_name(&cxl_bus_type, NULL, decoder); + if (!dev) + return -ENODEV; + + if (!is_endpoint_decoder(dev)) { + put_device(dev); + return -EINVAL; + } + + rc = down_write_killable(&cxl_region_rwsem); + if (rc) + goto out; + down_read(&cxl_dpa_rwsem); + rc = cxl_region_attach(cxlr, to_cxl_endpoint_decoder(dev), pos); + up_read(&cxl_dpa_rwsem); + up_write(&cxl_region_rwsem); +out: + put_device(dev); + return rc; +} + +static int detach_target(struct cxl_region *cxlr, int pos) +{ + struct cxl_region_params *p = &cxlr->params; + int rc; + + rc = down_write_killable(&cxl_region_rwsem); + if (rc) + return rc; + + if (pos >= p->interleave_ways) { + dev_dbg(&cxlr->dev, "position %d out of range %d\n", pos, + p->interleave_ways); + rc = -ENXIO; + goto out; + } + + if (!p->targets[pos]) { + rc = 0; + goto out; + } + + rc = cxl_region_detach(p->targets[pos]); +out: + up_write(&cxl_region_rwsem); + return rc; +} + +static size_t store_targetN(struct cxl_region *cxlr, const char *buf, int pos, + size_t len) +{ + int rc; + + if (sysfs_streq(buf, "\n")) + rc = detach_target(cxlr, pos); + else + rc = attach_target(cxlr, buf, pos); + + if (rc < 0) + return rc; + return len; +} + +#define TARGET_ATTR_RW(n) \ +static ssize_t target##n##_show( \ + struct device *dev, struct device_attribute *attr, char *buf) \ +{ \ + return show_targetN(to_cxl_region(dev), buf, (n)); \ +} \ +static ssize_t target##n##_store(struct device *dev, \ + struct device_attribute *attr, \ + const char *buf, size_t len) \ +{ \ + return store_targetN(to_cxl_region(dev), buf, (n), len); \ +} \ +static DEVICE_ATTR_RW(target##n) + +TARGET_ATTR_RW(0); +TARGET_ATTR_RW(1); +TARGET_ATTR_RW(2); +TARGET_ATTR_RW(3); +TARGET_ATTR_RW(4); +TARGET_ATTR_RW(5); +TARGET_ATTR_RW(6); +TARGET_ATTR_RW(7); +TARGET_ATTR_RW(8); +TARGET_ATTR_RW(9); +TARGET_ATTR_RW(10); +TARGET_ATTR_RW(11); +TARGET_ATTR_RW(12); +TARGET_ATTR_RW(13); +TARGET_ATTR_RW(14); +TARGET_ATTR_RW(15); + +static struct attribute *target_attrs[] = { + &dev_attr_target0.attr, + &dev_attr_target1.attr, + &dev_attr_target2.attr, + &dev_attr_target3.attr, + &dev_attr_target4.attr, + &dev_attr_target5.attr, + &dev_attr_target6.attr, + &dev_attr_target7.attr, + &dev_attr_target8.attr, + &dev_attr_target9.attr, + &dev_attr_target10.attr, + &dev_attr_target11.attr, + &dev_attr_target12.attr, + &dev_attr_target13.attr, + &dev_attr_target14.attr, + &dev_attr_target15.attr, + NULL, +}; + +static umode_t cxl_region_target_visible(struct kobject *kobj, + struct attribute *a, int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + + if (n < p->interleave_ways) + return a->mode; + return 0; +} + +static const struct attribute_group cxl_region_target_group = { + .attrs = target_attrs, + .is_visible = cxl_region_target_visible, +}; + +static const struct attribute_group *get_cxl_region_target_group(void) +{ + return &cxl_region_target_group; +} + +static const struct attribute_group *region_groups[] = { + &cxl_base_attribute_group, + &cxl_region_group, + &cxl_region_target_group, + NULL, +}; + +static void cxl_region_release(struct device *dev) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev->parent); + struct cxl_region *cxlr = to_cxl_region(dev); + int id = atomic_read(&cxlrd->region_id); + + /* + * Try to reuse the recently idled id rather than the cached + * next id to prevent the region id space from increasing + * unnecessarily. + */ + if (cxlr->id < id) + if (atomic_try_cmpxchg(&cxlrd->region_id, &id, cxlr->id)) { + memregion_free(id); + goto out; + } + + memregion_free(cxlr->id); +out: + put_device(dev->parent); + kfree(cxlr); +} + +const struct device_type cxl_region_type = { + .name = "cxl_region", + .release = cxl_region_release, + .groups = region_groups +}; + +bool is_cxl_region(struct device *dev) +{ + return dev->type == &cxl_region_type; +} +EXPORT_SYMBOL_NS_GPL(is_cxl_region, CXL); + +static struct cxl_region *to_cxl_region(struct device *dev) +{ + if (dev_WARN_ONCE(dev, dev->type != &cxl_region_type, + "not a cxl_region device\n")) + return NULL; + + return container_of(dev, struct cxl_region, dev); +} + +static void unregister_region(void *dev) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + int i; + + device_del(dev); + + /* + * Now that region sysfs is shutdown, the parameter block is now + * read-only, so no need to hold the region rwsem to access the + * region parameters. + */ + for (i = 0; i < p->interleave_ways; i++) + detach_target(cxlr, i); + + cxl_region_iomem_release(cxlr); + put_device(dev); +} + +static struct lock_class_key cxl_region_key; + +static struct cxl_region *cxl_region_alloc(struct cxl_root_decoder *cxlrd, int id) +{ + struct cxl_region *cxlr; + struct device *dev; + + cxlr = kzalloc(sizeof(*cxlr), GFP_KERNEL); + if (!cxlr) { + memregion_free(id); + return ERR_PTR(-ENOMEM); + } + + dev = &cxlr->dev; + device_initialize(dev); + lockdep_set_class(&dev->mutex, &cxl_region_key); + dev->parent = &cxlrd->cxlsd.cxld.dev; + /* + * Keep root decoder pinned through cxl_region_release to fixup + * region id allocations + */ + get_device(dev->parent); + device_set_pm_not_required(dev); + dev->bus = &cxl_bus_type; + dev->type = &cxl_region_type; + cxlr->id = id; + + return cxlr; +} + +/** + * devm_cxl_add_region - Adds a region to a decoder + * @cxlrd: root decoder + * @id: memregion id to create, or memregion_free() on failure + * @mode: mode for the endpoint decoders of this region + * @type: select whether this is an expander or accelerator (type-2 or type-3) + * + * This is the second step of region initialization. Regions exist within an + * address space which is mapped by a @cxlrd. + * + * Return: 0 if the region was added to the @cxlrd, else returns negative error + * code. The region will be named "regionZ" where Z is the unique region number. + */ +static struct cxl_region *devm_cxl_add_region(struct cxl_root_decoder *cxlrd, + int id, + enum cxl_decoder_mode mode, + enum cxl_decoder_type type) +{ + struct cxl_port *port = to_cxl_port(cxlrd->cxlsd.cxld.dev.parent); + struct cxl_region *cxlr; + struct device *dev; + int rc; + + cxlr = cxl_region_alloc(cxlrd, id); + if (IS_ERR(cxlr)) + return cxlr; + cxlr->mode = mode; + cxlr->type = type; + + dev = &cxlr->dev; + rc = dev_set_name(dev, "region%d", id); + if (rc) + goto err; + + rc = device_add(dev); + if (rc) + goto err; + + rc = devm_add_action_or_reset(port->uport, unregister_region, cxlr); + if (rc) + return ERR_PTR(rc); + + dev_dbg(port->uport, "%s: created %s\n", + dev_name(&cxlrd->cxlsd.cxld.dev), dev_name(dev)); + return cxlr; + +err: + put_device(dev); + return ERR_PTR(rc); +} + +static ssize_t create_pmem_region_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev); + + return sysfs_emit(buf, "region%u\n", atomic_read(&cxlrd->region_id)); +} + +static ssize_t create_pmem_region_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev); + struct cxl_region *cxlr; + int id, rc; + + rc = sscanf(buf, "region%d\n", &id); + if (rc != 1) + return -EINVAL; + + rc = memregion_alloc(GFP_KERNEL); + if (rc < 0) + return rc; + + if (atomic_cmpxchg(&cxlrd->region_id, id, rc) != id) { + memregion_free(rc); + return -EBUSY; + } + + cxlr = devm_cxl_add_region(cxlrd, id, CXL_DECODER_PMEM, + CXL_DECODER_EXPANDER); + if (IS_ERR(cxlr)) + return PTR_ERR(cxlr); + + return len; +} +DEVICE_ATTR_RW(create_pmem_region); + +static ssize_t region_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct cxl_decoder *cxld = to_cxl_decoder(dev); + ssize_t rc; + + rc = down_read_interruptible(&cxl_region_rwsem); + if (rc) + return rc; + + if (cxld->region) + rc = sysfs_emit(buf, "%s\n", dev_name(&cxld->region->dev)); + else + rc = sysfs_emit(buf, "\n"); + up_read(&cxl_region_rwsem); + + return rc; +} +DEVICE_ATTR_RO(region); + +static struct cxl_region * +cxl_find_region_by_name(struct cxl_root_decoder *cxlrd, const char *name) +{ + struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld; + struct device *region_dev; + + region_dev = device_find_child_by_name(&cxld->dev, name); + if (!region_dev) + return ERR_PTR(-ENODEV); + + return to_cxl_region(region_dev); +} + +static ssize_t delete_region_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev); + struct cxl_port *port = to_cxl_port(dev->parent); + struct cxl_region *cxlr; + + cxlr = cxl_find_region_by_name(cxlrd, buf); + if (IS_ERR(cxlr)) + return PTR_ERR(cxlr); + + devm_release_action(port->uport, unregister_region, cxlr); + put_device(&cxlr->dev); + + return len; +} +DEVICE_ATTR_WO(delete_region); + +static void cxl_pmem_region_release(struct device *dev) +{ + struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev); + int i; + + for (i = 0; i < cxlr_pmem->nr_mappings; i++) { + struct cxl_memdev *cxlmd = cxlr_pmem->mapping[i].cxlmd; + + put_device(&cxlmd->dev); + } + + kfree(cxlr_pmem); +} + +static const struct attribute_group *cxl_pmem_region_attribute_groups[] = { + &cxl_base_attribute_group, + NULL, +}; + +const struct device_type cxl_pmem_region_type = { + .name = "cxl_pmem_region", + .release = cxl_pmem_region_release, + .groups = cxl_pmem_region_attribute_groups, +}; + +bool is_cxl_pmem_region(struct device *dev) +{ + return dev->type == &cxl_pmem_region_type; +} +EXPORT_SYMBOL_NS_GPL(is_cxl_pmem_region, CXL); + +struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev) +{ + if (dev_WARN_ONCE(dev, !is_cxl_pmem_region(dev), + "not a cxl_pmem_region device\n")) + return NULL; + return container_of(dev, struct cxl_pmem_region, dev); +} +EXPORT_SYMBOL_NS_GPL(to_cxl_pmem_region, CXL); + +static struct lock_class_key cxl_pmem_region_key; + +static struct cxl_pmem_region *cxl_pmem_region_alloc(struct cxl_region *cxlr) +{ + struct cxl_region_params *p = &cxlr->params; + struct cxl_pmem_region *cxlr_pmem; + struct device *dev; + int i; + + down_read(&cxl_region_rwsem); + if (p->state != CXL_CONFIG_COMMIT) { + cxlr_pmem = ERR_PTR(-ENXIO); + goto out; + } + + cxlr_pmem = kzalloc(struct_size(cxlr_pmem, mapping, p->nr_targets), + GFP_KERNEL); + if (!cxlr_pmem) { + cxlr_pmem = ERR_PTR(-ENOMEM); + goto out; + } + + cxlr_pmem->hpa_range.start = p->res->start; + cxlr_pmem->hpa_range.end = p->res->end; + + /* Snapshot the region configuration underneath the cxl_region_rwsem */ + cxlr_pmem->nr_mappings = p->nr_targets; + for (i = 0; i < p->nr_targets; i++) { + struct cxl_endpoint_decoder *cxled = p->targets[i]; + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i]; + + m->cxlmd = cxlmd; + get_device(&cxlmd->dev); + m->start = cxled->dpa_res->start; + m->size = resource_size(cxled->dpa_res); + m->position = i; + } + + dev = &cxlr_pmem->dev; + cxlr_pmem->cxlr = cxlr; + device_initialize(dev); + lockdep_set_class(&dev->mutex, &cxl_pmem_region_key); + device_set_pm_not_required(dev); + dev->parent = &cxlr->dev; + dev->bus = &cxl_bus_type; + dev->type = &cxl_pmem_region_type; +out: + up_read(&cxl_region_rwsem); + + return cxlr_pmem; +} + +static void cxlr_pmem_unregister(void *dev) +{ + device_unregister(dev); +} + +/** + * devm_cxl_add_pmem_region() - add a cxl_region-to-nd_region bridge + * @cxlr: parent CXL region for this pmem region bridge device + * + * Return: 0 on success negative error code on failure. + */ +static int devm_cxl_add_pmem_region(struct cxl_region *cxlr) +{ + struct cxl_pmem_region *cxlr_pmem; + struct device *dev; + int rc; + + cxlr_pmem = cxl_pmem_region_alloc(cxlr); + if (IS_ERR(cxlr_pmem)) + return PTR_ERR(cxlr_pmem); + + dev = &cxlr_pmem->dev; + rc = dev_set_name(dev, "pmem_region%d", cxlr->id); + if (rc) + goto err; + + rc = device_add(dev); + if (rc) + goto err; + + dev_dbg(&cxlr->dev, "%s: register %s\n", dev_name(dev->parent), + dev_name(dev)); + + return devm_add_action_or_reset(&cxlr->dev, cxlr_pmem_unregister, dev); + +err: + put_device(dev); + return rc; +} + +static int cxl_region_probe(struct device *dev) +{ + struct cxl_region *cxlr = to_cxl_region(dev); + struct cxl_region_params *p = &cxlr->params; + int rc; + + rc = down_read_interruptible(&cxl_region_rwsem); + if (rc) { + dev_dbg(&cxlr->dev, "probe interrupted\n"); + return rc; + } + + if (p->state < CXL_CONFIG_COMMIT) { + dev_dbg(&cxlr->dev, "config state: %d\n", p->state); + rc = -ENXIO; + } + + /* + * From this point on any path that changes the region's state away from + * CXL_CONFIG_COMMIT is also responsible for releasing the driver. + */ + up_read(&cxl_region_rwsem); + + if (rc) + return rc; + + switch (cxlr->mode) { + case CXL_DECODER_PMEM: + return devm_cxl_add_pmem_region(cxlr); + default: + dev_dbg(&cxlr->dev, "unsupported region mode: %d\n", + cxlr->mode); + return -ENXIO; + } +} + +static struct cxl_driver cxl_region_driver = { + .name = "cxl_region", + .probe = cxl_region_probe, + .id = CXL_DEVICE_REGION, +}; + +int cxl_region_init(void) +{ + return cxl_driver_register(&cxl_region_driver); +} + +void cxl_region_exit(void) +{ + cxl_driver_unregister(&cxl_region_driver); +} + +MODULE_IMPORT_NS(CXL); +MODULE_ALIAS_CXL(CXL_DEVICE_REGION); diff --git a/drivers/cxl/core/regs.c b/drivers/cxl/core/regs.c new file mode 100644 index 000000000..39a129c57 --- /dev/null +++ b/drivers/cxl/core/regs.c @@ -0,0 +1,304 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2020 Intel Corporation. */ +#include <linux/io-64-nonatomic-lo-hi.h> +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/pci.h> +#include <cxlmem.h> +#include <cxlpci.h> + +/** + * DOC: cxl registers + * + * CXL device capabilities are enumerated by PCI DVSEC (Designated + * Vendor-specific) and / or descriptors provided by platform firmware. + * They can be defined as a set like the device and component registers + * mandated by CXL Section 8.1.12.2 Memory Device PCIe Capabilities and + * Extended Capabilities, or they can be individual capabilities + * appended to bridged and endpoint devices. + * + * Provide common infrastructure for enumerating and mapping these + * discrete capabilities. + */ + +/** + * cxl_probe_component_regs() - Detect CXL Component register blocks + * @dev: Host device of the @base mapping + * @base: Mapping containing the HDM Decoder Capability Header + * @map: Map object describing the register block information found + * + * See CXL 2.0 8.2.4 Component Register Layout and Definition + * See CXL 2.0 8.2.5.5 CXL Device Register Interface + * + * Probe for component register information and return it in map object. + */ +void cxl_probe_component_regs(struct device *dev, void __iomem *base, + struct cxl_component_reg_map *map) +{ + int cap, cap_count; + u32 cap_array; + + *map = (struct cxl_component_reg_map) { 0 }; + + /* + * CXL.cache and CXL.mem registers are at offset 0x1000 as defined in + * CXL 2.0 8.2.4 Table 141. + */ + base += CXL_CM_OFFSET; + + cap_array = readl(base + CXL_CM_CAP_HDR_OFFSET); + + if (FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, cap_array) != CM_CAP_HDR_CAP_ID) { + dev_err(dev, + "Couldn't locate the CXL.cache and CXL.mem capability array header.\n"); + return; + } + + /* It's assumed that future versions will be backward compatible */ + cap_count = FIELD_GET(CXL_CM_CAP_HDR_ARRAY_SIZE_MASK, cap_array); + + for (cap = 1; cap <= cap_count; cap++) { + void __iomem *register_block; + u32 hdr; + int decoder_cnt; + u16 cap_id, offset; + u32 length; + + hdr = readl(base + cap * 0x4); + + cap_id = FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, hdr); + offset = FIELD_GET(CXL_CM_CAP_PTR_MASK, hdr); + register_block = base + offset; + + switch (cap_id) { + case CXL_CM_CAP_CAP_ID_HDM: + dev_dbg(dev, "found HDM decoder capability (0x%x)\n", + offset); + + hdr = readl(register_block); + + decoder_cnt = cxl_hdm_decoder_count(hdr); + length = 0x20 * decoder_cnt + 0x10; + + map->hdm_decoder.valid = true; + map->hdm_decoder.offset = CXL_CM_OFFSET + offset; + map->hdm_decoder.size = length; + break; + default: + dev_dbg(dev, "Unknown CM cap ID: %d (0x%x)\n", cap_id, + offset); + break; + } + } +} +EXPORT_SYMBOL_NS_GPL(cxl_probe_component_regs, CXL); + +/** + * cxl_probe_device_regs() - Detect CXL Device register blocks + * @dev: Host device of the @base mapping + * @base: Mapping of CXL 2.0 8.2.8 CXL Device Register Interface + * @map: Map object describing the register block information found + * + * Probe for device register information and return it in map object. + */ +void cxl_probe_device_regs(struct device *dev, void __iomem *base, + struct cxl_device_reg_map *map) +{ + int cap, cap_count; + u64 cap_array; + + *map = (struct cxl_device_reg_map){ 0 }; + + cap_array = readq(base + CXLDEV_CAP_ARRAY_OFFSET); + if (FIELD_GET(CXLDEV_CAP_ARRAY_ID_MASK, cap_array) != + CXLDEV_CAP_ARRAY_CAP_ID) + return; + + cap_count = FIELD_GET(CXLDEV_CAP_ARRAY_COUNT_MASK, cap_array); + + for (cap = 1; cap <= cap_count; cap++) { + u32 offset, length; + u16 cap_id; + + cap_id = FIELD_GET(CXLDEV_CAP_HDR_CAP_ID_MASK, + readl(base + cap * 0x10)); + offset = readl(base + cap * 0x10 + 0x4); + length = readl(base + cap * 0x10 + 0x8); + + switch (cap_id) { + case CXLDEV_CAP_CAP_ID_DEVICE_STATUS: + dev_dbg(dev, "found Status capability (0x%x)\n", offset); + + map->status.valid = true; + map->status.offset = offset; + map->status.size = length; + break; + case CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX: + dev_dbg(dev, "found Mailbox capability (0x%x)\n", offset); + map->mbox.valid = true; + map->mbox.offset = offset; + map->mbox.size = length; + break; + case CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX: + dev_dbg(dev, "found Secondary Mailbox capability (0x%x)\n", offset); + break; + case CXLDEV_CAP_CAP_ID_MEMDEV: + dev_dbg(dev, "found Memory Device capability (0x%x)\n", offset); + map->memdev.valid = true; + map->memdev.offset = offset; + map->memdev.size = length; + break; + default: + if (cap_id >= 0x8000) + dev_dbg(dev, "Vendor cap ID: %#x offset: %#x\n", cap_id, offset); + else + dev_dbg(dev, "Unknown cap ID: %#x offset: %#x\n", cap_id, offset); + break; + } + } +} +EXPORT_SYMBOL_NS_GPL(cxl_probe_device_regs, CXL); + +void __iomem *devm_cxl_iomap_block(struct device *dev, resource_size_t addr, + resource_size_t length) +{ + void __iomem *ret_val; + struct resource *res; + + res = devm_request_mem_region(dev, addr, length, dev_name(dev)); + if (!res) { + resource_size_t end = addr + length - 1; + + dev_err(dev, "Failed to request region %pa-%pa\n", &addr, &end); + return NULL; + } + + ret_val = devm_ioremap(dev, addr, length); + if (!ret_val) + dev_err(dev, "Failed to map region %pr\n", res); + + return ret_val; +} + +int cxl_map_component_regs(struct pci_dev *pdev, + struct cxl_component_regs *regs, + struct cxl_register_map *map) +{ + struct device *dev = &pdev->dev; + resource_size_t phys_addr; + resource_size_t length; + + phys_addr = pci_resource_start(pdev, map->barno); + phys_addr += map->block_offset; + + phys_addr += map->component_map.hdm_decoder.offset; + length = map->component_map.hdm_decoder.size; + regs->hdm_decoder = devm_cxl_iomap_block(dev, phys_addr, length); + if (!regs->hdm_decoder) + return -ENOMEM; + + return 0; +} +EXPORT_SYMBOL_NS_GPL(cxl_map_component_regs, CXL); + +int cxl_map_device_regs(struct pci_dev *pdev, + struct cxl_device_regs *regs, + struct cxl_register_map *map) +{ + struct device *dev = &pdev->dev; + resource_size_t phys_addr; + + phys_addr = pci_resource_start(pdev, map->barno); + phys_addr += map->block_offset; + + if (map->device_map.status.valid) { + resource_size_t addr; + resource_size_t length; + + addr = phys_addr + map->device_map.status.offset; + length = map->device_map.status.size; + regs->status = devm_cxl_iomap_block(dev, addr, length); + if (!regs->status) + return -ENOMEM; + } + + if (map->device_map.mbox.valid) { + resource_size_t addr; + resource_size_t length; + + addr = phys_addr + map->device_map.mbox.offset; + length = map->device_map.mbox.size; + regs->mbox = devm_cxl_iomap_block(dev, addr, length); + if (!regs->mbox) + return -ENOMEM; + } + + if (map->device_map.memdev.valid) { + resource_size_t addr; + resource_size_t length; + + addr = phys_addr + map->device_map.memdev.offset; + length = map->device_map.memdev.size; + regs->memdev = devm_cxl_iomap_block(dev, addr, length); + if (!regs->memdev) + return -ENOMEM; + } + + return 0; +} +EXPORT_SYMBOL_NS_GPL(cxl_map_device_regs, CXL); + +static void cxl_decode_regblock(u32 reg_lo, u32 reg_hi, + struct cxl_register_map *map) +{ + map->block_offset = ((u64)reg_hi << 32) | + (reg_lo & CXL_DVSEC_REG_LOCATOR_BLOCK_OFF_LOW_MASK); + map->barno = FIELD_GET(CXL_DVSEC_REG_LOCATOR_BIR_MASK, reg_lo); + map->reg_type = FIELD_GET(CXL_DVSEC_REG_LOCATOR_BLOCK_ID_MASK, reg_lo); +} + +/** + * cxl_find_regblock() - Locate register blocks by type + * @pdev: The CXL PCI device to enumerate. + * @type: Register Block Indicator id + * @map: Enumeration output, clobbered on error + * + * Return: 0 if register block enumerated, negative error code otherwise + * + * A CXL DVSEC may point to one or more register blocks, search for them + * by @type. + */ +int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type, + struct cxl_register_map *map) +{ + u32 regloc_size, regblocks; + int regloc, i; + + map->block_offset = U64_MAX; + regloc = pci_find_dvsec_capability(pdev, PCI_DVSEC_VENDOR_ID_CXL, + CXL_DVSEC_REG_LOCATOR); + if (!regloc) + return -ENXIO; + + pci_read_config_dword(pdev, regloc + PCI_DVSEC_HEADER1, ®loc_size); + regloc_size = FIELD_GET(PCI_DVSEC_HEADER1_LENGTH_MASK, regloc_size); + + regloc += CXL_DVSEC_REG_LOCATOR_BLOCK1_OFFSET; + regblocks = (regloc_size - CXL_DVSEC_REG_LOCATOR_BLOCK1_OFFSET) / 8; + + for (i = 0; i < regblocks; i++, regloc += 8) { + u32 reg_lo, reg_hi; + + pci_read_config_dword(pdev, regloc, ®_lo); + pci_read_config_dword(pdev, regloc + 4, ®_hi); + + cxl_decode_regblock(reg_lo, reg_hi, map); + + if (map->reg_type == type) + return 0; + } + + map->block_offset = U64_MAX; + return -ENODEV; +} +EXPORT_SYMBOL_NS_GPL(cxl_find_regblock, CXL); diff --git a/drivers/cxl/core/suspend.c b/drivers/cxl/core/suspend.c new file mode 100644 index 000000000..a5984d96e --- /dev/null +++ b/drivers/cxl/core/suspend.c @@ -0,0 +1,24 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2022 Intel Corporation. All rights reserved. */ +#include <linux/atomic.h> +#include <linux/export.h> +#include "cxlmem.h" + +static atomic_t mem_active; + +bool cxl_mem_active(void) +{ + return atomic_read(&mem_active) != 0; +} + +void cxl_mem_active_inc(void) +{ + atomic_inc(&mem_active); +} +EXPORT_SYMBOL_NS_GPL(cxl_mem_active_inc, CXL); + +void cxl_mem_active_dec(void) +{ + atomic_dec(&mem_active); +} +EXPORT_SYMBOL_NS_GPL(cxl_mem_active_dec, CXL); |