diff options
Diffstat (limited to 'drivers/cxl/core/pci.c')
| -rw-r--r-- | drivers/cxl/core/pci.c | 850 |
1 files changed, 641 insertions, 209 deletions
diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index c7a7887ebdcf..5b023a0178a4 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -1,10 +1,12 @@ // SPDX-License-Identifier: GPL-2.0-only /* Copyright(c) 2021 Intel Corporation. All rights reserved. */ +#include <linux/units.h> #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 <linux/aer.h> #include <cxlpci.h> #include <cxlmem.h> #include <cxl.h> @@ -22,84 +24,52 @@ 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; +static int pci_get_port_num(struct pci_dev *pdev) +{ + u32 lnkcap; 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; + type = pci_pcie_type(pdev); + if (type != PCI_EXP_TYPE_DOWNSTREAM && type != PCI_EXP_TYPE_ROOT_PORT) + return -EINVAL; - 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, map.resource); - if (IS_ERR(dport)) { - ctx->error = PTR_ERR(dport); - return PTR_ERR(dport); - } - ctx->count++; + return -ENXIO; - return 0; + return FIELD_GET(PCI_EXP_LNKCAP_PN, lnkcap); } /** - * devm_cxl_port_enumerate_dports - enumerate downstream ports of the upstream port - * @port: cxl_port whose ->uport_dev is the upstream of dports to be enumerated + * __devm_cxl_add_dport_by_dev - allocate a dport by dport device + * @port: cxl_port that hosts the dport + * @dport_dev: 'struct device' of the dport * - * Returns a positive number of dports enumerated or a negative error - * code. + * Returns the allocated dport on success or ERR_PTR() of -errno on error */ -int devm_cxl_port_enumerate_dports(struct cxl_port *port) +struct cxl_dport *__devm_cxl_add_dport_by_dev(struct cxl_port *port, + struct device *dport_dev) { - struct pci_bus *bus = cxl_port_to_pci_bus(port); - struct cxl_walk_context ctx; - int type; + struct cxl_register_map map; + struct pci_dev *pdev; + int port_num, rc; - if (!bus) - return -ENXIO; + if (!dev_is_pci(dport_dev)) + return ERR_PTR(-EINVAL); - if (pci_is_root_bus(bus)) - type = PCI_EXP_TYPE_ROOT_PORT; - else - type = PCI_EXP_TYPE_DOWNSTREAM; + pdev = to_pci_dev(dport_dev); + port_num = pci_get_port_num(pdev); + if (port_num < 0) + return ERR_PTR(port_num); - ctx = (struct cxl_walk_context) { - .port = port, - .bus = bus, - .type = type, - }; - pci_walk_bus(bus, match_add_dports, &ctx); + rc = cxl_find_regblock(pdev, CXL_REGLOC_RBI_COMPONENT, &map); + if (rc) + return ERR_PTR(rc); - if (ctx.count == 0) - return -ENODEV; - if (ctx.error) - return ctx.error; - return ctx.count; + device_lock_assert(&port->dev); + return devm_cxl_add_dport(port, dport_dev, port_num, map.resource); } -EXPORT_SYMBOL_NS_GPL(devm_cxl_port_enumerate_dports, CXL); +EXPORT_SYMBOL_NS_GPL(__devm_cxl_add_dport_by_dev, "CXL"); static int cxl_dvsec_mem_range_valid(struct cxl_dev_state *cxlds, int id) { @@ -207,38 +177,7 @@ int cxl_await_media_ready(struct cxl_dev_state *cxlds) return 0; } -EXPORT_SYMBOL_NS_GPL(cxl_await_media_ready, CXL); - -static int wait_for_valid(struct pci_dev *pdev, int d) -{ - u32 val; - int rc; - - /* - * 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; -} +EXPORT_SYMBOL_NS_GPL(cxl_await_media_ready, "CXL"); static int cxl_set_mem_enable(struct cxl_dev_state *cxlds, u16 val) { @@ -281,9 +220,9 @@ static int devm_cxl_enable_mem(struct device *host, struct cxl_dev_state *cxlds) } /* require dvsec ranges to be covered by a locked platform window */ -static int dvsec_range_allowed(struct device *dev, void *arg) +static int dvsec_range_allowed(struct device *dev, const void *arg) { - struct range *dev_range = arg; + const struct range *dev_range = arg; struct cxl_decoder *cxld; if (!is_root_decoder(dev)) @@ -320,11 +259,13 @@ static int devm_cxl_enable_hdm(struct device *host, struct cxl_hdm *cxlhdm) return devm_add_action_or_reset(host, disable_hdm, cxlhdm); } -int cxl_dvsec_rr_decode(struct device *dev, int d, +int cxl_dvsec_rr_decode(struct cxl_dev_state *cxlds, struct cxl_endpoint_dvsec_info *info) { - struct pci_dev *pdev = to_pci_dev(dev); + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + struct device *dev = cxlds->dev; int hdm_count, rc, i, ranges = 0; + int d = cxlds->cxl_dvsec; u16 cap, ctrl; if (!d) { @@ -336,10 +277,6 @@ int cxl_dvsec_rr_decode(struct device *dev, int d, 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; @@ -355,17 +292,15 @@ int cxl_dvsec_rr_decode(struct device *dev, int d, if (!hdm_count || hdm_count > 2) return -EINVAL; - rc = wait_for_valid(pdev, d); - 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. */ + rc = pci_read_config_word(pdev, d + CXL_DVSEC_CTRL_OFFSET, &ctrl); + if (rc) + return rc; + info->mem_enabled = FIELD_GET(CXL_DVSEC_MEM_ENABLE, ctrl); if (!info->mem_enabled) return 0; @@ -374,6 +309,10 @@ int cxl_dvsec_rr_decode(struct device *dev, int d, u64 base, size; u32 temp; + rc = cxl_dvsec_mem_range_valid(cxlds, i); + if (rc) + return rc; + rc = pci_read_config_dword( pdev, d + CXL_DVSEC_RANGE_SIZE_HIGH(i), &temp); if (rc) @@ -388,10 +327,6 @@ int cxl_dvsec_rr_decode(struct device *dev, int d, size |= temp & CXL_DVSEC_MEM_SIZE_LOW_MASK; if (!size) { - info->dvsec_range[i] = (struct range) { - .start = 0, - .end = CXL_RESOURCE_NONE, - }; continue; } @@ -409,19 +344,17 @@ int cxl_dvsec_rr_decode(struct device *dev, int d, base |= temp & CXL_DVSEC_MEM_BASE_LOW_MASK; - info->dvsec_range[i] = (struct range) { + info->dvsec_range[ranges++] = (struct range) { .start = base, .end = base + size - 1 }; - - ranges++; } info->ranges = ranges; return 0; } -EXPORT_SYMBOL_NS_GPL(cxl_dvsec_rr_decode, CXL); +EXPORT_SYMBOL_NS_GPL(cxl_dvsec_rr_decode, "CXL"); /** * cxl_hdm_decode_init() - Setup HDM decoding for the endpoint @@ -450,9 +383,40 @@ int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm, */ if (global_ctrl & CXL_HDM_DECODER_ENABLE || (!hdm && info->mem_enabled)) return devm_cxl_enable_mem(&port->dev, cxlds); - else if (!hdm) + + /* + * If the HDM Decoder Capability does not exist and DVSEC was + * not setup, the DVSEC based emulation cannot be used. + */ + if (!hdm) return -ENODEV; + /* The HDM Decoder Capability exists but is globally disabled. */ + + /* + * If the DVSEC CXL Range registers are not enabled, just + * enable and use the HDM Decoder Capability registers. + */ + if (!info->mem_enabled) { + rc = devm_cxl_enable_hdm(&port->dev, cxlhdm); + if (rc) + return rc; + + return devm_cxl_enable_mem(&port->dev, cxlds); + } + + /* + * 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. Check if at least one DVSEC range is enabled and allowed by + * the platform. That is, the DVSEC range must be covered by a locked + * platform window (CFMWS). Fail otherwise as the endpoint's decoders + * cannot be used. + */ + 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); @@ -461,7 +425,7 @@ int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm, return -ENODEV; } - for (i = 0, allowed = 0; info->mem_enabled && i < info->ranges; i++) { + for (i = 0, allowed = 0; i < info->ranges; i++) { struct device *cxld_dev; cxld_dev = device_find_child(&root->dev, &info->dvsec_range[i], @@ -476,29 +440,13 @@ int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm, } if (!allowed) { - cxl_set_mem_enable(cxlds, 0); - info->mem_enabled = 0; + dev_err(dev, "Range register decodes outside platform defined CXL ranges.\n"); + return -ENXIO; } - /* - * 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 0; - - rc = devm_cxl_enable_hdm(&port->dev, cxlhdm); - if (rc) - return rc; - - return devm_cxl_enable_mem(&port->dev, cxlds); + return 0; } -EXPORT_SYMBOL_NS_GPL(cxl_hdm_decode_init, CXL); +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 @@ -516,14 +464,14 @@ EXPORT_SYMBOL_NS_GPL(cxl_hdm_decode_init, CXL); FIELD_PREP(CXL_DOE_TABLE_ACCESS_ENTRY_HANDLE, (entry_handle))) static int cxl_cdat_get_length(struct device *dev, - struct pci_doe_mb *cdat_doe, + struct pci_doe_mb *doe_mb, size_t *length) { __le32 request = CDAT_DOE_REQ(0); __le32 response[2]; int rc; - rc = pci_doe(cdat_doe, PCI_DVSEC_VENDOR_ID_CXL, + rc = pci_doe(doe_mb, PCI_VENDOR_ID_CXL, CXL_DOE_PROTOCOL_TABLE_ACCESS, &request, sizeof(request), &response, sizeof(response)); @@ -541,60 +489,72 @@ static int cxl_cdat_get_length(struct device *dev, } static int cxl_cdat_read_table(struct device *dev, - struct pci_doe_mb *cdat_doe, - void *cdat_table, size_t *cdat_length) + struct pci_doe_mb *doe_mb, + struct cdat_doe_rsp *rsp, size_t *length) { - size_t length = *cdat_length + sizeof(__le32); - __le32 *data = cdat_table; - int entry_handle = 0; + size_t received, remaining = *length; + unsigned int entry_handle = 0; + union cdat_data *data; __le32 saved_dw = 0; do { __le32 request = CDAT_DOE_REQ(entry_handle); - struct cdat_entry_header *entry; - size_t entry_dw; int rc; - rc = pci_doe(cdat_doe, PCI_DVSEC_VENDOR_ID_CXL, + rc = pci_doe(doe_mb, PCI_VENDOR_ID_CXL, CXL_DOE_PROTOCOL_TABLE_ACCESS, &request, sizeof(request), - data, length); + rsp, sizeof(*rsp) + remaining); if (rc < 0) { dev_err(dev, "DOE failed: %d", rc); return rc; } - /* 1 DW Table Access Response Header + CDAT entry */ - entry = (struct cdat_entry_header *)(data + 1); - if ((entry_handle == 0 && - rc != sizeof(__le32) + sizeof(struct cdat_header)) || - (entry_handle > 0 && - (rc < sizeof(__le32) + sizeof(*entry) || - rc != sizeof(__le32) + le16_to_cpu(entry->length)))) + if (rc < sizeof(*rsp)) return -EIO; + data = (union cdat_data *)rsp->data; + received = rc - sizeof(*rsp); + + if (entry_handle == 0) { + if (received != sizeof(data->header)) + return -EIO; + } else { + if (received < sizeof(data->entry) || + received != le16_to_cpu(data->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(data[0])); - entry_dw = rc / sizeof(__le32); - /* Skip Header */ - entry_dw -= 1; + le32_to_cpu(rsp->doe_header)); + /* * Table Access Response Header overwrote the last DW of * previous entry, so restore that DW */ - *data = saved_dw; - length -= entry_dw * sizeof(__le32); - data += entry_dw; - saved_dw = *data; + rsp->doe_header = saved_dw; + remaining -= received; + rsp = (void *)rsp + received; + saved_dw = rsp->doe_header; } while (entry_handle != CXL_DOE_TABLE_ACCESS_LAST_ENTRY); /* Length in CDAT header may exceed concatenation of CDAT entries */ - *cdat_length -= length - sizeof(__le32); + *length -= remaining; return 0; } +static unsigned char cdat_checksum(void *buf, size_t size) +{ + unsigned char sum, *data = buf; + size_t i; + + for (sum = 0, i = 0; i < size; i++) + sum += data[i]; + return sum; +} + /** * read_cdat_data - Read the CDAT data on this port * @port: Port to read data from @@ -603,75 +563,105 @@ static int cxl_cdat_read_table(struct device *dev, */ void read_cdat_data(struct cxl_port *port) { - struct cxl_memdev *cxlmd = to_cxl_memdev(port->uport_dev); - struct device *host = cxlmd->dev.parent; + struct device *uport = port->uport_dev; struct device *dev = &port->dev; - struct pci_doe_mb *cdat_doe; - size_t cdat_length; - void *cdat_table; + struct pci_doe_mb *doe_mb; + struct pci_dev *pdev = NULL; + struct cxl_memdev *cxlmd; + struct cdat_doe_rsp *buf; + size_t table_length, length; int rc; - if (!dev_is_pci(host)) + if (is_cxl_memdev(uport)) { + struct device *host; + + cxlmd = to_cxl_memdev(uport); + host = cxlmd->dev.parent; + if (dev_is_pci(host)) + pdev = to_pci_dev(host); + } else if (dev_is_pci(uport)) { + pdev = to_pci_dev(uport); + } + + if (!pdev) return; - cdat_doe = pci_find_doe_mailbox(to_pci_dev(host), - PCI_DVSEC_VENDOR_ID_CXL, - CXL_DOE_PROTOCOL_TABLE_ACCESS); - if (!cdat_doe) { + + doe_mb = pci_find_doe_mailbox(pdev, PCI_VENDOR_ID_CXL, + CXL_DOE_PROTOCOL_TABLE_ACCESS); + if (!doe_mb) { dev_dbg(dev, "No CDAT mailbox\n"); return; } port->cdat_available = true; - if (cxl_cdat_get_length(dev, cdat_doe, &cdat_length)) { + if (cxl_cdat_get_length(dev, doe_mb, &length)) { dev_dbg(dev, "No CDAT length\n"); return; } - cdat_table = devm_kzalloc(dev, cdat_length + sizeof(__le32), - GFP_KERNEL); - if (!cdat_table) - return; + /* + * The begin of the CDAT buffer needs space for additional 4 + * bytes for the DOE header. Table data starts afterwards. + */ + buf = devm_kzalloc(dev, sizeof(*buf) + length, GFP_KERNEL); + if (!buf) + goto err; - rc = cxl_cdat_read_table(dev, cdat_doe, cdat_table, &cdat_length); - if (rc) { - /* Don't leave table data allocated on error */ - devm_kfree(dev, cdat_table); - dev_err(dev, "CDAT data read error\n"); - return; - } + table_length = length; - port->cdat.table = cdat_table + sizeof(__le32); - port->cdat.length = cdat_length; + rc = cxl_cdat_read_table(dev, doe_mb, buf, &length); + if (rc) + goto err; + + if (table_length != length) + dev_warn(dev, "Malformed CDAT table length (%zu:%zu), discarding trailing data\n", + table_length, length); + + if (cdat_checksum(buf->data, length)) + goto err; + + port->cdat.table = buf->data; + port->cdat.length = length; + + return; +err: + /* Don't leave table data allocated on error */ + devm_kfree(dev, buf); + dev_err(dev, "Failed to read/validate CDAT.\n"); } -EXPORT_SYMBOL_NS_GPL(read_cdat_data, CXL); +EXPORT_SYMBOL_NS_GPL(read_cdat_data, "CXL"); -void cxl_cor_error_detected(struct pci_dev *pdev) +static void __cxl_handle_cor_ras(struct cxl_dev_state *cxlds, + void __iomem *ras_base) { - struct cxl_dev_state *cxlds = pci_get_drvdata(pdev); void __iomem *addr; u32 status; - if (!cxlds->regs.ras) + if (!ras_base) return; - addr = cxlds->regs.ras + CXL_RAS_CORRECTABLE_STATUS_OFFSET; + addr = ras_base + CXL_RAS_CORRECTABLE_STATUS_OFFSET; status = readl(addr); if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) { writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr); trace_cxl_aer_correctable_error(cxlds->cxlmd, status); } } -EXPORT_SYMBOL_NS_GPL(cxl_cor_error_detected, CXL); + +static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds) +{ + return __cxl_handle_cor_ras(cxlds, cxlds->regs.ras); +} /* CXL spec rev3.0 8.2.4.16.1 */ -static void header_log_copy(struct cxl_dev_state *cxlds, u32 *log) +static void header_log_copy(void __iomem *ras_base, u32 *log) { void __iomem *addr; u32 *log_addr; int i, log_u32_size = CXL_HEADERLOG_SIZE / sizeof(u32); - addr = cxlds->regs.ras + CXL_RAS_HEADER_LOG_OFFSET; + addr = ras_base + CXL_RAS_HEADER_LOG_OFFSET; log_addr = log; for (i = 0; i < log_u32_size; i++) { @@ -685,17 +675,18 @@ static void header_log_copy(struct cxl_dev_state *cxlds, u32 *log) * Log the state of the RAS status registers and prepare them to log the * next error status. Return 1 if reset needed. */ -static bool cxl_report_and_clear(struct cxl_dev_state *cxlds) +static bool __cxl_handle_ras(struct cxl_dev_state *cxlds, + void __iomem *ras_base) { u32 hl[CXL_HEADERLOG_SIZE_U32]; void __iomem *addr; u32 status; u32 fe; - if (!cxlds->regs.ras) + if (!ras_base) return false; - addr = cxlds->regs.ras + CXL_RAS_UNCORRECTABLE_STATUS_OFFSET; + addr = ras_base + CXL_RAS_UNCORRECTABLE_STATUS_OFFSET; status = readl(addr); if (!(status & CXL_RAS_UNCORRECTABLE_STATUS_MASK)) return false; @@ -703,7 +694,7 @@ static bool cxl_report_and_clear(struct cxl_dev_state *cxlds) /* If multiple errors, log header points to first error from ctrl reg */ if (hweight32(status) > 1) { void __iomem *rcc_addr = - cxlds->regs.ras + CXL_RAS_CAP_CONTROL_OFFSET; + ras_base + CXL_RAS_CAP_CONTROL_OFFSET; fe = BIT(FIELD_GET(CXL_RAS_CAP_CONTROL_FE_MASK, readl(rcc_addr))); @@ -711,13 +702,204 @@ static bool cxl_report_and_clear(struct cxl_dev_state *cxlds) fe = status; } - header_log_copy(cxlds, hl); + header_log_copy(ras_base, hl); trace_cxl_aer_uncorrectable_error(cxlds->cxlmd, status, fe, hl); writel(status & CXL_RAS_UNCORRECTABLE_STATUS_MASK, addr); return true; } +static bool cxl_handle_endpoint_ras(struct cxl_dev_state *cxlds) +{ + return __cxl_handle_ras(cxlds, cxlds->regs.ras); +} + +#ifdef CONFIG_PCIEAER_CXL + +static void cxl_dport_map_rch_aer(struct cxl_dport *dport) +{ + resource_size_t aer_phys; + struct device *host; + u16 aer_cap; + + aer_cap = cxl_rcrb_to_aer(dport->dport_dev, dport->rcrb.base); + if (aer_cap) { + host = dport->reg_map.host; + aer_phys = aer_cap + dport->rcrb.base; + dport->regs.dport_aer = devm_cxl_iomap_block(host, aer_phys, + sizeof(struct aer_capability_regs)); + } +} + +static void cxl_dport_map_ras(struct cxl_dport *dport) +{ + struct cxl_register_map *map = &dport->reg_map; + struct device *dev = dport->dport_dev; + + if (!map->component_map.ras.valid) + dev_dbg(dev, "RAS registers not found\n"); + else if (cxl_map_component_regs(map, &dport->regs.component, + BIT(CXL_CM_CAP_CAP_ID_RAS))) + dev_dbg(dev, "Failed to map RAS capability.\n"); +} + +static void cxl_disable_rch_root_ints(struct cxl_dport *dport) +{ + void __iomem *aer_base = dport->regs.dport_aer; + u32 aer_cmd_mask, aer_cmd; + + if (!aer_base) + return; + + /* + * Disable RCH root port command interrupts. + * CXL 3.0 12.2.1.1 - RCH Downstream Port-detected Errors + * + * This sequence may not be necessary. CXL spec states disabling + * the root cmd register's interrupts is required. But, PCI spec + * shows these are disabled by default on reset. + */ + aer_cmd_mask = (PCI_ERR_ROOT_CMD_COR_EN | + PCI_ERR_ROOT_CMD_NONFATAL_EN | + PCI_ERR_ROOT_CMD_FATAL_EN); + aer_cmd = readl(aer_base + PCI_ERR_ROOT_COMMAND); + aer_cmd &= ~aer_cmd_mask; + writel(aer_cmd, aer_base + PCI_ERR_ROOT_COMMAND); +} + +/** + * cxl_dport_init_ras_reporting - Setup CXL RAS report on this dport + * @dport: the cxl_dport that needs to be initialized + * @host: host device for devm operations + */ +void cxl_dport_init_ras_reporting(struct cxl_dport *dport, struct device *host) +{ + dport->reg_map.host = host; + cxl_dport_map_ras(dport); + + if (dport->rch) { + struct pci_host_bridge *host_bridge = to_pci_host_bridge(dport->dport_dev); + + if (!host_bridge->native_aer) + return; + + cxl_dport_map_rch_aer(dport); + cxl_disable_rch_root_ints(dport); + } +} +EXPORT_SYMBOL_NS_GPL(cxl_dport_init_ras_reporting, "CXL"); + +static void cxl_handle_rdport_cor_ras(struct cxl_dev_state *cxlds, + struct cxl_dport *dport) +{ + return __cxl_handle_cor_ras(cxlds, dport->regs.ras); +} + +static bool cxl_handle_rdport_ras(struct cxl_dev_state *cxlds, + struct cxl_dport *dport) +{ + return __cxl_handle_ras(cxlds, dport->regs.ras); +} + +/* + * Copy the AER capability registers using 32 bit read accesses. + * This is necessary because RCRB AER capability is MMIO mapped. Clear the + * status after copying. + * + * @aer_base: base address of AER capability block in RCRB + * @aer_regs: destination for copying AER capability + */ +static bool cxl_rch_get_aer_info(void __iomem *aer_base, + struct aer_capability_regs *aer_regs) +{ + int read_cnt = sizeof(struct aer_capability_regs) / sizeof(u32); + u32 *aer_regs_buf = (u32 *)aer_regs; + int n; + + if (!aer_base) + return false; + + /* Use readl() to guarantee 32-bit accesses */ + for (n = 0; n < read_cnt; n++) + aer_regs_buf[n] = readl(aer_base + n * sizeof(u32)); + + writel(aer_regs->uncor_status, aer_base + PCI_ERR_UNCOR_STATUS); + writel(aer_regs->cor_status, aer_base + PCI_ERR_COR_STATUS); + + return true; +} + +/* Get AER severity. Return false if there is no error. */ +static bool cxl_rch_get_aer_severity(struct aer_capability_regs *aer_regs, + int *severity) +{ + if (aer_regs->uncor_status & ~aer_regs->uncor_mask) { + if (aer_regs->uncor_status & PCI_ERR_ROOT_FATAL_RCV) + *severity = AER_FATAL; + else + *severity = AER_NONFATAL; + return true; + } + + if (aer_regs->cor_status & ~aer_regs->cor_mask) { + *severity = AER_CORRECTABLE; + return true; + } + + return false; +} + +static void cxl_handle_rdport_errors(struct cxl_dev_state *cxlds) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + struct aer_capability_regs aer_regs; + struct cxl_dport *dport; + int severity; + + struct cxl_port *port __free(put_cxl_port) = + cxl_pci_find_port(pdev, &dport); + if (!port) + return; + + if (!cxl_rch_get_aer_info(dport->regs.dport_aer, &aer_regs)) + return; + + if (!cxl_rch_get_aer_severity(&aer_regs, &severity)) + return; + + pci_print_aer(pdev, severity, &aer_regs); + + if (severity == AER_CORRECTABLE) + cxl_handle_rdport_cor_ras(cxlds, dport); + else + cxl_handle_rdport_ras(cxlds, dport); +} + +#else +static void cxl_handle_rdport_errors(struct cxl_dev_state *cxlds) { } +#endif + +void cxl_cor_error_detected(struct pci_dev *pdev) +{ + struct cxl_dev_state *cxlds = pci_get_drvdata(pdev); + struct device *dev = &cxlds->cxlmd->dev; + + scoped_guard(device, dev) { + if (!dev->driver) { + dev_warn(&pdev->dev, + "%s: memdev disabled, abort error handling\n", + dev_name(dev)); + return; + } + + if (cxlds->rcd) + cxl_handle_rdport_errors(cxlds); + + cxl_handle_endpoint_cor_ras(cxlds); + } +} +EXPORT_SYMBOL_NS_GPL(cxl_cor_error_detected, "CXL"); + pci_ers_result_t cxl_error_detected(struct pci_dev *pdev, pci_channel_state_t state) { @@ -726,13 +908,25 @@ pci_ers_result_t cxl_error_detected(struct pci_dev *pdev, struct device *dev = &cxlmd->dev; bool ue; - /* - * A frozen channel indicates an impending reset which is fatal to - * CXL.mem operation, and will likely crash the system. On the off - * chance the situation is recoverable dump the status of the RAS - * capability registers and bounce the active state of the memdev. - */ - ue = cxl_report_and_clear(cxlds); + scoped_guard(device, dev) { + if (!dev->driver) { + dev_warn(&pdev->dev, + "%s: memdev disabled, abort error handling\n", + dev_name(dev)); + return PCI_ERS_RESULT_DISCONNECT; + } + + if (cxlds->rcd) + cxl_handle_rdport_errors(cxlds); + /* + * A frozen channel indicates an impending reset which is fatal to + * CXL.mem operation, and will likely crash the system. On the off + * chance the situation is recoverable dump the status of the RAS + * capability registers and bounce the active state of the memdev. + */ + ue = cxl_handle_endpoint_ras(cxlds); + } + switch (state) { case pci_channel_io_normal: @@ -754,4 +948,242 @@ pci_ers_result_t cxl_error_detected(struct pci_dev *pdev, } return PCI_ERS_RESULT_NEED_RESET; } -EXPORT_SYMBOL_NS_GPL(cxl_error_detected, CXL); +EXPORT_SYMBOL_NS_GPL(cxl_error_detected, "CXL"); + +static int cxl_flit_size(struct pci_dev *pdev) +{ + if (cxl_pci_flit_256(pdev)) + return 256; + + return 68; +} + +/** + * cxl_pci_get_latency - calculate the link latency for the PCIe link + * @pdev: PCI device + * + * return: calculated latency or 0 for no latency + * + * CXL Memory Device SW Guide v1.0 2.11.4 Link latency calculation + * Link latency = LinkPropagationLatency + FlitLatency + RetimerLatency + * LinkProgationLatency is negligible, so 0 will be used + * RetimerLatency is assumed to be negligible and 0 will be used + * FlitLatency = FlitSize / LinkBandwidth + * FlitSize is defined by spec. CXL rev3.0 4.2.1. + * 68B flit is used up to 32GT/s. >32GT/s, 256B flit size is used. + * The FlitLatency is converted to picoseconds. + */ +long cxl_pci_get_latency(struct pci_dev *pdev) +{ + long bw; + + bw = pcie_link_speed_mbps(pdev); + if (bw < 0) + return 0; + bw /= BITS_PER_BYTE; + + return cxl_flit_size(pdev) * MEGA / bw; +} + +static int __cxl_endpoint_decoder_reset_detected(struct device *dev, void *data) +{ + struct cxl_port *port = data; + struct cxl_decoder *cxld; + struct cxl_hdm *cxlhdm; + void __iomem *hdm; + u32 ctrl; + + if (!is_endpoint_decoder(dev)) + return 0; + + cxld = to_cxl_decoder(dev); + if ((cxld->flags & CXL_DECODER_F_ENABLE) == 0) + return 0; + + cxlhdm = dev_get_drvdata(&port->dev); + hdm = cxlhdm->regs.hdm_decoder; + ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); + + return !FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl); +} + +bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port) +{ + return device_for_each_child(&port->dev, port, + __cxl_endpoint_decoder_reset_detected); +} +EXPORT_SYMBOL_NS_GPL(cxl_endpoint_decoder_reset_detected, "CXL"); + +int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c) +{ + int speed, bw; + u16 lnksta; + u32 width; + + speed = pcie_link_speed_mbps(pdev); + if (speed < 0) + return speed; + speed /= BITS_PER_BYTE; + + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnksta); + width = FIELD_GET(PCI_EXP_LNKSTA_NLW, lnksta); + bw = speed * width; + + for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) { + c[i].read_bandwidth = bw; + c[i].write_bandwidth = bw; + } + + return 0; +} + +/* + * Set max timeout such that platforms will optimize GPF flow to avoid + * the implied worst-case scenario delays. On a sane platform, all + * devices should always complete GPF within the energy budget of + * the GPF flow. The kernel does not have enough information to pick + * anything better than "maximize timeouts and hope it works". + * + * A misbehaving device could block forward progress of GPF for all + * the other devices, exhausting the energy budget of the platform. + * However, the spec seems to assume that moving on from slow to respond + * devices is a virtue. It is not possible to know that, in actuality, + * the slow to respond device is *the* most critical device in the + * system to wait. + */ +#define GPF_TIMEOUT_BASE_MAX 2 +#define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */ + +u16 cxl_gpf_get_dvsec(struct device *dev) +{ + struct pci_dev *pdev; + bool is_port = true; + u16 dvsec; + + if (!dev_is_pci(dev)) + return 0; + + pdev = to_pci_dev(dev); + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ENDPOINT) + is_port = false; + + dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL, + is_port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF); + if (!dvsec) + dev_warn(dev, "%s GPF DVSEC not present\n", + is_port ? "Port" : "Device"); + return dvsec; +} +EXPORT_SYMBOL_NS_GPL(cxl_gpf_get_dvsec, "CXL"); + +static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase) +{ + u64 base, scale; + int rc, offset; + u16 ctrl; + + switch (phase) { + case 1: + offset = CXL_DVSEC_PORT_GPF_PHASE_1_CONTROL_OFFSET; + base = CXL_DVSEC_PORT_GPF_PHASE_1_TMO_BASE_MASK; + scale = CXL_DVSEC_PORT_GPF_PHASE_1_TMO_SCALE_MASK; + break; + case 2: + offset = CXL_DVSEC_PORT_GPF_PHASE_2_CONTROL_OFFSET; + base = CXL_DVSEC_PORT_GPF_PHASE_2_TMO_BASE_MASK; + scale = CXL_DVSEC_PORT_GPF_PHASE_2_TMO_SCALE_MASK; + break; + default: + return -EINVAL; + } + + rc = pci_read_config_word(pdev, dvsec + offset, &ctrl); + if (rc) + return rc; + + if (FIELD_GET(base, ctrl) == GPF_TIMEOUT_BASE_MAX && + FIELD_GET(scale, ctrl) == GPF_TIMEOUT_SCALE_MAX) + return 0; + + ctrl = FIELD_PREP(base, GPF_TIMEOUT_BASE_MAX); + ctrl |= FIELD_PREP(scale, GPF_TIMEOUT_SCALE_MAX); + + rc = pci_write_config_word(pdev, dvsec + offset, ctrl); + if (!rc) + pci_dbg(pdev, "Port GPF phase %d timeout: %d0 secs\n", + phase, GPF_TIMEOUT_BASE_MAX); + + return rc; +} + +int cxl_gpf_port_setup(struct cxl_dport *dport) +{ + if (!dport) + return -EINVAL; + + if (!dport->gpf_dvsec) { + struct pci_dev *pdev; + int dvsec; + + dvsec = cxl_gpf_get_dvsec(dport->dport_dev); + if (!dvsec) + return -EINVAL; + + dport->gpf_dvsec = dvsec; + pdev = to_pci_dev(dport->dport_dev); + update_gpf_port_dvsec(pdev, dport->gpf_dvsec, 1); + update_gpf_port_dvsec(pdev, dport->gpf_dvsec, 2); + } + + return 0; +} + +struct cxl_walk_context { + struct pci_bus *bus; + struct cxl_port *port; + int type; + int error; + int count; +}; + +static int count_dports(struct pci_dev *pdev, void *data) +{ + struct cxl_walk_context *ctx = data; + int type = pci_pcie_type(pdev); + + if (pdev->bus != ctx->bus) + return 0; + if (!pci_is_pcie(pdev)) + return 0; + if (type != ctx->type) + return 0; + + ctx->count++; + return 0; +} + +int cxl_port_get_possible_dports(struct cxl_port *port) +{ + struct pci_bus *bus = cxl_port_to_pci_bus(port); + struct cxl_walk_context ctx; + int type; + + if (!bus) { + dev_err(&port->dev, "No PCI bus found for port %s\n", + dev_name(&port->dev)); + 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) { + .bus = bus, + .type = type, + }; + pci_walk_bus(bus, count_dports, &ctx); + + return ctx.count; +} |