// SPDX-License-Identifier: GPL-2.0-only /* Copyright(c) 2021 Intel Corporation. All rights reserved. */ #include #include #include #include #include #include #include "cxlpci.h" #include "cxl.h" static unsigned long cfmws_to_decoder_flags(int restrictions) { unsigned long flags = CXL_DECODER_F_ENABLE; if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_TYPE2) flags |= CXL_DECODER_F_TYPE2; if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_TYPE3) flags |= CXL_DECODER_F_TYPE3; if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_VOLATILE) flags |= CXL_DECODER_F_RAM; if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_PMEM) flags |= CXL_DECODER_F_PMEM; if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_FIXED) flags |= CXL_DECODER_F_LOCK; return flags; } static int cxl_acpi_cfmws_verify(struct device *dev, struct acpi_cedt_cfmws *cfmws) { int rc, expected_len; unsigned int ways; if (cfmws->interleave_arithmetic != ACPI_CEDT_CFMWS_ARITHMETIC_MODULO) { dev_err(dev, "CFMWS Unsupported Interleave Arithmetic\n"); return -EINVAL; } if (!IS_ALIGNED(cfmws->base_hpa, SZ_256M)) { dev_err(dev, "CFMWS Base HPA not 256MB aligned\n"); return -EINVAL; } if (!IS_ALIGNED(cfmws->window_size, SZ_256M)) { dev_err(dev, "CFMWS Window Size not 256MB aligned\n"); return -EINVAL; } rc = cxl_to_ways(cfmws->interleave_ways, &ways); if (rc) { dev_err(dev, "CFMWS Interleave Ways (%d) invalid\n", cfmws->interleave_ways); return -EINVAL; } expected_len = struct_size(cfmws, interleave_targets, ways); if (cfmws->header.length < expected_len) { dev_err(dev, "CFMWS length %d less than expected %d\n", cfmws->header.length, expected_len); return -EINVAL; } if (cfmws->header.length > expected_len) dev_dbg(dev, "CFMWS length %d greater than expected %d\n", cfmws->header.length, expected_len); return 0; } struct cxl_cfmws_context { struct device *dev; struct cxl_port *root_port; struct resource *cxl_res; int id; }; static int cxl_parse_cfmws(union acpi_subtable_headers *header, void *arg, const unsigned long end) { int target_map[CXL_DECODER_MAX_INTERLEAVE]; struct cxl_cfmws_context *ctx = arg; struct cxl_port *root_port = ctx->root_port; struct resource *cxl_res = ctx->cxl_res; struct cxl_root_decoder *cxlrd; struct device *dev = ctx->dev; struct acpi_cedt_cfmws *cfmws; struct cxl_decoder *cxld; unsigned int ways, i, ig; struct resource *res; int rc; cfmws = (struct acpi_cedt_cfmws *) header; rc = cxl_acpi_cfmws_verify(dev, cfmws); if (rc) { dev_err(dev, "CFMWS range %#llx-%#llx not registered\n", cfmws->base_hpa, cfmws->base_hpa + cfmws->window_size - 1); return 0; } rc = cxl_to_ways(cfmws->interleave_ways, &ways); if (rc) return rc; rc = cxl_to_granularity(cfmws->granularity, &ig); if (rc) return rc; for (i = 0; i < ways; i++) target_map[i] = cfmws->interleave_targets[i]; res = kzalloc(sizeof(*res), GFP_KERNEL); if (!res) return -ENOMEM; res->name = kasprintf(GFP_KERNEL, "CXL Window %d", ctx->id++); if (!res->name) goto err_name; res->start = cfmws->base_hpa; res->end = cfmws->base_hpa + cfmws->window_size - 1; res->flags = IORESOURCE_MEM; /* add to the local resource tracking to establish a sort order */ rc = insert_resource(cxl_res, res); if (rc) goto err_insert; cxlrd = cxl_root_decoder_alloc(root_port, ways); if (IS_ERR(cxlrd)) return 0; cxld = &cxlrd->cxlsd.cxld; cxld->flags = cfmws_to_decoder_flags(cfmws->restrictions); cxld->target_type = CXL_DECODER_EXPANDER; cxld->hpa_range = (struct range) { .start = res->start, .end = res->end, }; cxld->interleave_ways = ways; /* * Minimize the x1 granularity to advertise support for any * valid region granularity */ if (ways == 1) ig = CXL_DECODER_MIN_GRANULARITY; cxld->interleave_granularity = ig; rc = cxl_decoder_add(cxld, target_map); if (rc) put_device(&cxld->dev); else rc = cxl_decoder_autoremove(dev, cxld); if (rc) { dev_err(dev, "Failed to add decode range: %pr", res); return rc; } dev_dbg(dev, "add: %s node: %d range [%#llx - %#llx]\n", dev_name(&cxld->dev), phys_to_target_node(cxld->hpa_range.start), cxld->hpa_range.start, cxld->hpa_range.end); return 0; err_insert: kfree(res->name); err_name: kfree(res); return -ENOMEM; } __mock struct acpi_device *to_cxl_host_bridge(struct device *host, struct device *dev) { struct acpi_device *adev = to_acpi_device(dev); if (!acpi_pci_find_root(adev->handle)) return NULL; if (strcmp(acpi_device_hid(adev), "ACPI0016") == 0) return adev; return NULL; } /* * A host bridge is a dport to a CFMWS decode and it is a uport to the * dport (PCIe Root Ports) in the host bridge. */ static int add_host_bridge_uport(struct device *match, void *arg) { struct cxl_port *root_port = arg; struct device *host = root_port->dev.parent; struct acpi_device *bridge = to_cxl_host_bridge(host, match); struct acpi_pci_root *pci_root; struct cxl_dport *dport; struct cxl_port *port; int rc; if (!bridge) return 0; dport = cxl_find_dport_by_dev(root_port, match); if (!dport) { dev_dbg(host, "host bridge expected and not found\n"); return 0; } /* * Note that this lookup already succeeded in * to_cxl_host_bridge(), so no need to check for failure here */ pci_root = acpi_pci_find_root(bridge->handle); rc = devm_cxl_register_pci_bus(host, match, pci_root->bus); if (rc) return rc; port = devm_cxl_add_port(host, match, dport->component_reg_phys, dport); if (IS_ERR(port)) return PTR_ERR(port); return 0; } struct cxl_chbs_context { struct device *dev; unsigned long long uid; resource_size_t chbcr; }; static int cxl_get_chbcr(union acpi_subtable_headers *header, void *arg, const unsigned long end) { struct cxl_chbs_context *ctx = arg; struct acpi_cedt_chbs *chbs; if (ctx->chbcr) return 0; chbs = (struct acpi_cedt_chbs *) header; if (ctx->uid != chbs->uid) return 0; ctx->chbcr = chbs->base; return 0; } static int add_host_bridge_dport(struct device *match, void *arg) { acpi_status status; unsigned long long uid; struct cxl_dport *dport; struct cxl_chbs_context ctx; struct cxl_port *root_port = arg; struct device *host = root_port->dev.parent; struct acpi_device *bridge = to_cxl_host_bridge(host, match); if (!bridge) return 0; status = acpi_evaluate_integer(bridge->handle, METHOD_NAME__UID, NULL, &uid); if (status != AE_OK) { dev_err(host, "unable to retrieve _UID of %s\n", dev_name(match)); return -ENODEV; } ctx = (struct cxl_chbs_context) { .dev = host, .uid = uid, }; acpi_table_parse_cedt(ACPI_CEDT_TYPE_CHBS, cxl_get_chbcr, &ctx); if (ctx.chbcr == 0) { dev_warn(host, "No CHBS found for Host Bridge: %s\n", dev_name(match)); return 0; } dport = devm_cxl_add_dport(root_port, match, uid, ctx.chbcr); if (IS_ERR(dport)) { dev_err(host, "failed to add downstream port: %s\n", dev_name(match)); return PTR_ERR(dport); } dev_dbg(host, "add dport%llu: %s\n", uid, dev_name(match)); return 0; } static int add_root_nvdimm_bridge(struct device *match, void *data) { struct cxl_decoder *cxld; struct cxl_port *root_port = data; struct cxl_nvdimm_bridge *cxl_nvb; struct device *host = root_port->dev.parent; if (!is_root_decoder(match)) return 0; cxld = to_cxl_decoder(match); if (!(cxld->flags & CXL_DECODER_F_PMEM)) return 0; cxl_nvb = devm_cxl_add_nvdimm_bridge(host, root_port); if (IS_ERR(cxl_nvb)) { dev_dbg(host, "failed to register pmem\n"); return PTR_ERR(cxl_nvb); } dev_dbg(host, "%s: add: %s\n", dev_name(&root_port->dev), dev_name(&cxl_nvb->dev)); return 1; } static struct lock_class_key cxl_root_key; static void cxl_acpi_lock_reset_class(void *dev) { device_lock_reset_class(dev); } static void del_cxl_resource(struct resource *res) { kfree(res->name); kfree(res); } static void cxl_set_public_resource(struct resource *priv, struct resource *pub) { priv->desc = (unsigned long) pub; } static struct resource *cxl_get_public_resource(struct resource *priv) { return (struct resource *) priv->desc; } static void remove_cxl_resources(void *data) { struct resource *res, *next, *cxl = data; for (res = cxl->child; res; res = next) { struct resource *victim = cxl_get_public_resource(res); next = res->sibling; remove_resource(res); if (victim) { remove_resource(victim); kfree(victim); } del_cxl_resource(res); } } /** * add_cxl_resources() - reflect CXL fixed memory windows in iomem_resource * @cxl_res: A standalone resource tree where each CXL window is a sibling * * Walk each CXL window in @cxl_res and add it to iomem_resource potentially * expanding its boundaries to ensure that any conflicting resources become * children. If a window is expanded it may then conflict with a another window * entry and require the window to be truncated or trimmed. Consider this * situation: * * |-- "CXL Window 0" --||----- "CXL Window 1" -----| * |--------------- "System RAM" -------------| * * ...where platform firmware has established as System RAM resource across 2 * windows, but has left some portion of window 1 for dynamic CXL region * provisioning. In this case "Window 0" will span the entirety of the "System * RAM" span, and "CXL Window 1" is truncated to the remaining tail past the end * of that "System RAM" resource. */ static int add_cxl_resources(struct resource *cxl_res) { struct resource *res, *new, *next; for (res = cxl_res->child; res; res = next) { new = kzalloc(sizeof(*new), GFP_KERNEL); if (!new) return -ENOMEM; new->name = res->name; new->start = res->start; new->end = res->end; new->flags = IORESOURCE_MEM; new->desc = IORES_DESC_CXL; /* * Record the public resource in the private cxl_res tree for * later removal. */ cxl_set_public_resource(res, new); insert_resource_expand_to_fit(&iomem_resource, new); next = res->sibling; while (next && resource_overlaps(new, next)) { if (resource_contains(new, next)) { struct resource *_next = next->sibling; remove_resource(next); del_cxl_resource(next); next = _next; } else next->start = new->end + 1; } } return 0; } static int pair_cxl_resource(struct device *dev, void *data) { struct resource *cxl_res = data; struct resource *p; if (!is_root_decoder(dev)) return 0; for (p = cxl_res->child; p; p = p->sibling) { struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev); struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld; struct resource res = { .start = cxld->hpa_range.start, .end = cxld->hpa_range.end, .flags = IORESOURCE_MEM, }; if (resource_contains(p, &res)) { cxlrd->res = cxl_get_public_resource(p); break; } } return 0; } static int cxl_acpi_probe(struct platform_device *pdev) { int rc; struct resource *cxl_res; struct cxl_port *root_port; struct device *host = &pdev->dev; struct acpi_device *adev = ACPI_COMPANION(host); struct cxl_cfmws_context ctx; device_lock_set_class(&pdev->dev, &cxl_root_key); rc = devm_add_action_or_reset(&pdev->dev, cxl_acpi_lock_reset_class, &pdev->dev); if (rc) return rc; cxl_res = devm_kzalloc(host, sizeof(*cxl_res), GFP_KERNEL); if (!cxl_res) return -ENOMEM; cxl_res->name = "CXL mem"; cxl_res->start = 0; cxl_res->end = -1; cxl_res->flags = IORESOURCE_MEM; root_port = devm_cxl_add_port(host, host, CXL_RESOURCE_NONE, NULL); if (IS_ERR(root_port)) return PTR_ERR(root_port); rc = bus_for_each_dev(adev->dev.bus, NULL, root_port, add_host_bridge_dport); if (rc < 0) return rc; rc = devm_add_action_or_reset(host, remove_cxl_resources, cxl_res); if (rc) return rc; ctx = (struct cxl_cfmws_context) { .dev = host, .root_port = root_port, .cxl_res = cxl_res, }; rc = acpi_table_parse_cedt(ACPI_CEDT_TYPE_CFMWS, cxl_parse_cfmws, &ctx); if (rc < 0) return -ENXIO; rc = add_cxl_resources(cxl_res); if (rc) return rc; /* * Populate the root decoders with their related iomem resource, * if present */ device_for_each_child(&root_port->dev, cxl_res, pair_cxl_resource); /* * Root level scanned with host-bridge as dports, now scan host-bridges * for their role as CXL uports to their CXL-capable PCIe Root Ports. */ rc = bus_for_each_dev(adev->dev.bus, NULL, root_port, add_host_bridge_uport); if (rc < 0) return rc; if (IS_ENABLED(CONFIG_CXL_PMEM)) rc = device_for_each_child(&root_port->dev, root_port, add_root_nvdimm_bridge); if (rc < 0) return rc; /* In case PCI is scanned before ACPI re-trigger memdev attach */ return cxl_bus_rescan(); } static const struct acpi_device_id cxl_acpi_ids[] = { { "ACPI0017" }, { }, }; MODULE_DEVICE_TABLE(acpi, cxl_acpi_ids); static const struct platform_device_id cxl_test_ids[] = { { "cxl_acpi" }, { }, }; MODULE_DEVICE_TABLE(platform, cxl_test_ids); static struct platform_driver cxl_acpi_driver = { .probe = cxl_acpi_probe, .driver = { .name = KBUILD_MODNAME, .acpi_match_table = cxl_acpi_ids, }, .id_table = cxl_test_ids, }; module_platform_driver(cxl_acpi_driver); MODULE_LICENSE("GPL v2"); MODULE_IMPORT_NS(CXL); MODULE_IMPORT_NS(ACPI);