diff options
Diffstat (limited to 'arch/powerpc/platforms/powernv/ocxl.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/ocxl.c | 485 |
1 files changed, 485 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/ocxl.c b/arch/powerpc/platforms/powernv/ocxl.c new file mode 100644 index 000000000..ecdad219d --- /dev/null +++ b/arch/powerpc/platforms/powernv/ocxl.c @@ -0,0 +1,485 @@ +// SPDX-License-Identifier: GPL-2.0+ +// Copyright 2017 IBM Corp. +#include <asm/pnv-ocxl.h> +#include <asm/opal.h> +#include <misc/ocxl-config.h> +#include "pci.h" + +#define PNV_OCXL_TL_P9_RECV_CAP 0x000000000000000Full +#define PNV_OCXL_ACTAG_MAX 64 +/* PASIDs are 20-bit, but on P9, NPU can only handle 15 bits */ +#define PNV_OCXL_PASID_BITS 15 +#define PNV_OCXL_PASID_MAX ((1 << PNV_OCXL_PASID_BITS) - 1) + +#define AFU_PRESENT (1 << 31) +#define AFU_INDEX_MASK 0x3F000000 +#define AFU_INDEX_SHIFT 24 +#define ACTAG_MASK 0xFFF + + +struct actag_range { + u16 start; + u16 count; +}; + +struct npu_link { + struct list_head list; + int domain; + int bus; + int dev; + u16 fn_desired_actags[8]; + struct actag_range fn_actags[8]; + bool assignment_done; +}; +static struct list_head links_list = LIST_HEAD_INIT(links_list); +static DEFINE_MUTEX(links_list_lock); + + +/* + * opencapi actags handling: + * + * When sending commands, the opencapi device references the memory + * context it's targeting with an 'actag', which is really an alias + * for a (BDF, pasid) combination. When it receives a command, the NPU + * must do a lookup of the actag to identify the memory context. The + * hardware supports a finite number of actags per link (64 for + * POWER9). + * + * The device can carry multiple functions, and each function can have + * multiple AFUs. Each AFU advertises in its config space the number + * of desired actags. The host must configure in the config space of + * the AFU how many actags the AFU is really allowed to use (which can + * be less than what the AFU desires). + * + * When a PCI function is probed by the driver, it has no visibility + * about the other PCI functions and how many actags they'd like, + * which makes it impossible to distribute actags fairly among AFUs. + * + * Unfortunately, the only way to know how many actags a function + * desires is by looking at the data for each AFU in the config space + * and add them up. Similarly, the only way to know how many actags + * all the functions of the physical device desire is by adding the + * previously computed function counts. Then we can match that against + * what the hardware supports. + * + * To get a comprehensive view, we use a 'pci fixup': at the end of + * PCI enumeration, each function counts how many actags its AFUs + * desire and we save it in a 'npu_link' structure, shared between all + * the PCI functions of a same device. Therefore, when the first + * function is probed by the driver, we can get an idea of the total + * count of desired actags for the device, and assign the actags to + * the AFUs, by pro-rating if needed. + */ + +static int find_dvsec_from_pos(struct pci_dev *dev, int dvsec_id, int pos) +{ + int vsec = pos; + u16 vendor, id; + + while ((vsec = pci_find_next_ext_capability(dev, vsec, + OCXL_EXT_CAP_ID_DVSEC))) { + pci_read_config_word(dev, vsec + OCXL_DVSEC_VENDOR_OFFSET, + &vendor); + pci_read_config_word(dev, vsec + OCXL_DVSEC_ID_OFFSET, &id); + if (vendor == PCI_VENDOR_ID_IBM && id == dvsec_id) + return vsec; + } + return 0; +} + +static int find_dvsec_afu_ctrl(struct pci_dev *dev, u8 afu_idx) +{ + int vsec = 0; + u8 idx; + + while ((vsec = find_dvsec_from_pos(dev, OCXL_DVSEC_AFU_CTRL_ID, + vsec))) { + pci_read_config_byte(dev, vsec + OCXL_DVSEC_AFU_CTRL_AFU_IDX, + &idx); + if (idx == afu_idx) + return vsec; + } + return 0; +} + +static int get_max_afu_index(struct pci_dev *dev, int *afu_idx) +{ + int pos; + u32 val; + + pos = find_dvsec_from_pos(dev, OCXL_DVSEC_FUNC_ID, 0); + if (!pos) + return -ESRCH; + + pci_read_config_dword(dev, pos + OCXL_DVSEC_FUNC_OFF_INDEX, &val); + if (val & AFU_PRESENT) + *afu_idx = (val & AFU_INDEX_MASK) >> AFU_INDEX_SHIFT; + else + *afu_idx = -1; + return 0; +} + +static int get_actag_count(struct pci_dev *dev, int afu_idx, int *actag) +{ + int pos; + u16 actag_sup; + + pos = find_dvsec_afu_ctrl(dev, afu_idx); + if (!pos) + return -ESRCH; + + pci_read_config_word(dev, pos + OCXL_DVSEC_AFU_CTRL_ACTAG_SUP, + &actag_sup); + *actag = actag_sup & ACTAG_MASK; + return 0; +} + +static struct npu_link *find_link(struct pci_dev *dev) +{ + struct npu_link *link; + + list_for_each_entry(link, &links_list, list) { + /* The functions of a device all share the same link */ + if (link->domain == pci_domain_nr(dev->bus) && + link->bus == dev->bus->number && + link->dev == PCI_SLOT(dev->devfn)) { + return link; + } + } + + /* link doesn't exist yet. Allocate one */ + link = kzalloc(sizeof(struct npu_link), GFP_KERNEL); + if (!link) + return NULL; + link->domain = pci_domain_nr(dev->bus); + link->bus = dev->bus->number; + link->dev = PCI_SLOT(dev->devfn); + list_add(&link->list, &links_list); + return link; +} + +static void pnv_ocxl_fixup_actag(struct pci_dev *dev) +{ + struct pci_controller *hose = pci_bus_to_host(dev->bus); + struct pnv_phb *phb = hose->private_data; + struct npu_link *link; + int rc, afu_idx = -1, i, actag; + + if (!machine_is(powernv)) + return; + + if (phb->type != PNV_PHB_NPU_OCAPI) + return; + + mutex_lock(&links_list_lock); + + link = find_link(dev); + if (!link) { + dev_warn(&dev->dev, "couldn't update actag information\n"); + mutex_unlock(&links_list_lock); + return; + } + + /* + * Check how many actags are desired for the AFUs under that + * function and add it to the count for the link + */ + rc = get_max_afu_index(dev, &afu_idx); + if (rc) { + /* Most likely an invalid config space */ + dev_dbg(&dev->dev, "couldn't find AFU information\n"); + afu_idx = -1; + } + + link->fn_desired_actags[PCI_FUNC(dev->devfn)] = 0; + for (i = 0; i <= afu_idx; i++) { + /* + * AFU index 'holes' are allowed. So don't fail if we + * can't read the actag info for an index + */ + rc = get_actag_count(dev, i, &actag); + if (rc) + continue; + link->fn_desired_actags[PCI_FUNC(dev->devfn)] += actag; + } + dev_dbg(&dev->dev, "total actags for function: %d\n", + link->fn_desired_actags[PCI_FUNC(dev->devfn)]); + + mutex_unlock(&links_list_lock); +} +DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pnv_ocxl_fixup_actag); + +static u16 assign_fn_actags(u16 desired, u16 total) +{ + u16 count; + + if (total <= PNV_OCXL_ACTAG_MAX) + count = desired; + else + count = PNV_OCXL_ACTAG_MAX * desired / total; + + return count; +} + +static void assign_actags(struct npu_link *link) +{ + u16 actag_count, range_start = 0, total_desired = 0; + int i; + + for (i = 0; i < 8; i++) + total_desired += link->fn_desired_actags[i]; + + for (i = 0; i < 8; i++) { + if (link->fn_desired_actags[i]) { + actag_count = assign_fn_actags( + link->fn_desired_actags[i], + total_desired); + link->fn_actags[i].start = range_start; + link->fn_actags[i].count = actag_count; + range_start += actag_count; + WARN_ON(range_start >= PNV_OCXL_ACTAG_MAX); + } + pr_debug("link %x:%x:%x fct %d actags: start=%d count=%d (desired=%d)\n", + link->domain, link->bus, link->dev, i, + link->fn_actags[i].start, link->fn_actags[i].count, + link->fn_desired_actags[i]); + } + link->assignment_done = true; +} + +int pnv_ocxl_get_actag(struct pci_dev *dev, u16 *base, u16 *enabled, + u16 *supported) +{ + struct npu_link *link; + + mutex_lock(&links_list_lock); + + link = find_link(dev); + if (!link) { + dev_err(&dev->dev, "actag information not found\n"); + mutex_unlock(&links_list_lock); + return -ENODEV; + } + /* + * On p9, we only have 64 actags per link, so they must be + * shared by all the functions of the same adapter. We counted + * the desired actag counts during PCI enumeration, so that we + * can allocate a pro-rated number of actags to each function. + */ + if (!link->assignment_done) + assign_actags(link); + + *base = link->fn_actags[PCI_FUNC(dev->devfn)].start; + *enabled = link->fn_actags[PCI_FUNC(dev->devfn)].count; + *supported = link->fn_desired_actags[PCI_FUNC(dev->devfn)]; + + mutex_unlock(&links_list_lock); + return 0; +} +EXPORT_SYMBOL_GPL(pnv_ocxl_get_actag); + +int pnv_ocxl_get_pasid_count(struct pci_dev *dev, int *count) +{ + struct npu_link *link; + int i, rc = -EINVAL; + + /* + * The number of PASIDs (process address space ID) which can + * be used by a function depends on how many functions exist + * on the device. The NPU needs to be configured to know how + * many bits are available to PASIDs and how many are to be + * used by the function BDF indentifier. + * + * We only support one AFU-carrying function for now. + */ + mutex_lock(&links_list_lock); + + link = find_link(dev); + if (!link) { + dev_err(&dev->dev, "actag information not found\n"); + mutex_unlock(&links_list_lock); + return -ENODEV; + } + + for (i = 0; i < 8; i++) + if (link->fn_desired_actags[i] && (i == PCI_FUNC(dev->devfn))) { + *count = PNV_OCXL_PASID_MAX; + rc = 0; + break; + } + + mutex_unlock(&links_list_lock); + dev_dbg(&dev->dev, "%d PASIDs available for function\n", + rc ? 0 : *count); + return rc; +} +EXPORT_SYMBOL_GPL(pnv_ocxl_get_pasid_count); + +static void set_templ_rate(unsigned int templ, unsigned int rate, char *buf) +{ + int shift, idx; + + WARN_ON(templ > PNV_OCXL_TL_MAX_TEMPLATE); + idx = (PNV_OCXL_TL_MAX_TEMPLATE - templ) / 2; + shift = 4 * (1 - ((PNV_OCXL_TL_MAX_TEMPLATE - templ) % 2)); + buf[idx] |= rate << shift; +} + +int pnv_ocxl_get_tl_cap(struct pci_dev *dev, long *cap, + char *rate_buf, int rate_buf_size) +{ + if (rate_buf_size != PNV_OCXL_TL_RATE_BUF_SIZE) + return -EINVAL; + /* + * The TL capabilities are a characteristic of the NPU, so + * we go with hard-coded values. + * + * The receiving rate of each template is encoded on 4 bits. + * + * On P9: + * - templates 0 -> 3 are supported + * - templates 0, 1 and 3 have a 0 receiving rate + * - template 2 has receiving rate of 1 (extra cycle) + */ + memset(rate_buf, 0, rate_buf_size); + set_templ_rate(2, 1, rate_buf); + *cap = PNV_OCXL_TL_P9_RECV_CAP; + return 0; +} +EXPORT_SYMBOL_GPL(pnv_ocxl_get_tl_cap); + +int pnv_ocxl_set_tl_conf(struct pci_dev *dev, long cap, + uint64_t rate_buf_phys, int rate_buf_size) +{ + struct pci_controller *hose = pci_bus_to_host(dev->bus); + struct pnv_phb *phb = hose->private_data; + int rc; + + if (rate_buf_size != PNV_OCXL_TL_RATE_BUF_SIZE) + return -EINVAL; + + rc = opal_npu_tl_set(phb->opal_id, dev->devfn, cap, + rate_buf_phys, rate_buf_size); + if (rc) { + dev_err(&dev->dev, "Can't configure host TL: %d\n", rc); + return -EINVAL; + } + return 0; +} +EXPORT_SYMBOL_GPL(pnv_ocxl_set_tl_conf); + +int pnv_ocxl_get_xsl_irq(struct pci_dev *dev, int *hwirq) +{ + int rc; + + rc = of_property_read_u32(dev->dev.of_node, "ibm,opal-xsl-irq", hwirq); + if (rc) { + dev_err(&dev->dev, + "Can't get translation interrupt for device\n"); + return rc; + } + return 0; +} +EXPORT_SYMBOL_GPL(pnv_ocxl_get_xsl_irq); + +void pnv_ocxl_unmap_xsl_regs(void __iomem *dsisr, void __iomem *dar, + void __iomem *tfc, void __iomem *pe_handle) +{ + iounmap(dsisr); + iounmap(dar); + iounmap(tfc); + iounmap(pe_handle); +} +EXPORT_SYMBOL_GPL(pnv_ocxl_unmap_xsl_regs); + +int pnv_ocxl_map_xsl_regs(struct pci_dev *dev, void __iomem **dsisr, + void __iomem **dar, void __iomem **tfc, + void __iomem **pe_handle) +{ + u64 reg; + int i, j, rc = 0; + void __iomem *regs[4]; + + /* + * opal stores the mmio addresses of the DSISR, DAR, TFC and + * PE_HANDLE registers in a device tree property, in that + * order + */ + for (i = 0; i < 4; i++) { + rc = of_property_read_u64_index(dev->dev.of_node, + "ibm,opal-xsl-mmio", i, ®); + if (rc) + break; + regs[i] = ioremap(reg, 8); + if (!regs[i]) { + rc = -EINVAL; + break; + } + } + if (rc) { + dev_err(&dev->dev, "Can't map translation mmio registers\n"); + for (j = i - 1; j >= 0; j--) + iounmap(regs[j]); + } else { + *dsisr = regs[0]; + *dar = regs[1]; + *tfc = regs[2]; + *pe_handle = regs[3]; + } + return rc; +} +EXPORT_SYMBOL_GPL(pnv_ocxl_map_xsl_regs); + +struct spa_data { + u64 phb_opal_id; + u32 bdfn; +}; + +int pnv_ocxl_spa_setup(struct pci_dev *dev, void *spa_mem, int PE_mask, + void **platform_data) +{ + struct pci_controller *hose = pci_bus_to_host(dev->bus); + struct pnv_phb *phb = hose->private_data; + struct spa_data *data; + u32 bdfn; + int rc; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + bdfn = (dev->bus->number << 8) | dev->devfn; + rc = opal_npu_spa_setup(phb->opal_id, bdfn, virt_to_phys(spa_mem), + PE_mask); + if (rc) { + dev_err(&dev->dev, "Can't setup Shared Process Area: %d\n", rc); + kfree(data); + return rc; + } + data->phb_opal_id = phb->opal_id; + data->bdfn = bdfn; + *platform_data = (void *) data; + return 0; +} +EXPORT_SYMBOL_GPL(pnv_ocxl_spa_setup); + +void pnv_ocxl_spa_release(void *platform_data) +{ + struct spa_data *data = (struct spa_data *) platform_data; + int rc; + + rc = opal_npu_spa_setup(data->phb_opal_id, data->bdfn, 0, 0); + WARN_ON(rc); + kfree(data); +} +EXPORT_SYMBOL_GPL(pnv_ocxl_spa_release); + +int pnv_ocxl_spa_remove_pe_from_cache(void *platform_data, int pe_handle) +{ + struct spa_data *data = (struct spa_data *) platform_data; + int rc; + + rc = opal_npu_spa_clear_cache(data->phb_opal_id, data->bdfn, pe_handle); + return rc; +} +EXPORT_SYMBOL_GPL(pnv_ocxl_spa_remove_pe_from_cache); |