diff options
Diffstat (limited to 'drivers/cxl')
| -rw-r--r-- | drivers/cxl/cxlmem.h | 14 | ||||
| -rw-r--r-- | drivers/cxl/cxlpci.h | 13 | ||||
| -rw-r--r-- | drivers/cxl/pci.c | 119 |
3 files changed, 146 insertions, 0 deletions
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h index 5cf5329e13a9..00f55f4066b9 100644 --- a/drivers/cxl/cxlmem.h +++ b/drivers/cxl/cxlmem.h @@ -90,6 +90,18 @@ struct cxl_mbox_cmd { #define CXL_CAPACITY_MULTIPLIER SZ_256M /** + * struct cxl_endpoint_dvsec_info - Cached DVSEC info + * @mem_enabled: cached value of mem_enabled in the DVSEC, PCIE_DEVICE + * @ranges: Number of active HDM ranges this device uses. + * @dvsec_range: cached attributes of the ranges in the DVSEC, PCIE_DEVICE + */ +struct cxl_endpoint_dvsec_info { + bool mem_enabled; + int ranges; + struct range dvsec_range[2]; +}; + +/** * struct cxl_dev_state - The driver device state * * cxl_dev_state represents the CXL driver/device state. It provides an @@ -118,6 +130,7 @@ struct cxl_mbox_cmd { * @next_volatile_bytes: volatile capacity change pending device reset * @next_persistent_bytes: persistent capacity change pending device reset * @component_reg_phys: register base of component registers + * @info: Cached DVSEC information about the device. * @mbox_send: @dev specific transport for transmitting mailbox commands * * See section 8.2.9.5.2 Capacity Configuration and Label Storage for @@ -149,6 +162,7 @@ struct cxl_dev_state { u64 next_persistent_bytes; resource_size_t component_reg_phys; + struct cxl_endpoint_dvsec_info info; int (*mbox_send)(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd); }; diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h index 766de340c4ce..329e7ea3f36a 100644 --- a/drivers/cxl/cxlpci.h +++ b/drivers/cxl/cxlpci.h @@ -17,6 +17,19 @@ /* CXL 2.0 8.1.3: PCIe DVSEC for CXL Device */ #define CXL_DVSEC_PCIE_DEVICE 0 +#define CXL_DVSEC_CAP_OFFSET 0xA +#define CXL_DVSEC_MEM_CAPABLE BIT(2) +#define CXL_DVSEC_HDM_COUNT_MASK GENMASK(5, 4) +#define CXL_DVSEC_CTRL_OFFSET 0xC +#define CXL_DVSEC_MEM_ENABLE BIT(2) +#define CXL_DVSEC_RANGE_SIZE_HIGH(i) (0x18 + (i * 0x10)) +#define CXL_DVSEC_RANGE_SIZE_LOW(i) (0x1C + (i * 0x10)) +#define CXL_DVSEC_MEM_INFO_VALID BIT(0) +#define CXL_DVSEC_MEM_ACTIVE BIT(1) +#define CXL_DVSEC_MEM_SIZE_LOW_MASK GENMASK(31, 28) +#define CXL_DVSEC_RANGE_BASE_HIGH(i) (0x20 + (i * 0x10)) +#define CXL_DVSEC_RANGE_BASE_LOW(i) (0x24 + (i * 0x10)) +#define CXL_DVSEC_MEM_BASE_LOW_MASK GENMASK(31, 28) /* CXL 2.0 8.1.4: Non-CXL Function Map DVSEC */ #define CXL_DVSEC_FUNCTION_MAP 2 diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index c94002166084..6b3270246545 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -386,6 +386,120 @@ static int cxl_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type, return rc; } +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_dvsec_ranges(struct cxl_dev_state *cxlds) +{ + struct cxl_endpoint_dvsec_info *info = &cxlds->info; + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int d = cxlds->cxl_dvsec; + int hdm_count, rc, i; + u16 cap, ctrl; + + if (!d) + 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)) + 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) + return rc; + + info->mem_enabled = FIELD_GET(CXL_DVSEC_MEM_ENABLE, ctrl); + + 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) + info->ranges++; + } + + return 0; +} + static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) { struct cxl_register_map map; @@ -449,6 +563,11 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) if (rc) return rc; + rc = cxl_dvsec_ranges(cxlds); + if (rc) + dev_warn(&pdev->dev, + "Failed to get DVSEC range information (%d)\n", rc); + cxlmd = devm_cxl_add_memdev(cxlds); if (IS_ERR(cxlmd)) return PTR_ERR(cxlmd); |