diff options
| -rw-r--r-- | drivers/acpi/pci_root.c | 67 | ||||
| -rw-r--r-- | include/acpi/acpi_bus.h | 6 | ||||
| -rw-r--r-- | include/linux/acpi.h | 4 |
3 files changed, 63 insertions, 14 deletions
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index 57be89cb3966..1e683c115ee0 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -168,20 +168,45 @@ static void decode_osc_control(struct acpi_pci_root *root, char *msg, u32 word) ARRAY_SIZE(pci_osc_control_bit)); } +static inline bool is_pcie(struct acpi_pci_root *root) +{ + return root->bridge_type == ACPI_BRIDGE_TYPE_PCIE; +} + +static inline bool is_cxl(struct acpi_pci_root *root) +{ + return root->bridge_type == ACPI_BRIDGE_TYPE_CXL; +} + static u8 pci_osc_uuid_str[] = "33DB4D5B-1FF7-401C-9657-7441C03DD766"; +static u8 cxl_osc_uuid_str[] = "68F2D50B-C469-4d8A-BD3D-941A103FD3FC"; + +static char *to_uuid(struct acpi_pci_root *root) +{ + if (is_cxl(root)) + return cxl_osc_uuid_str; + return pci_osc_uuid_str; +} + +static int cap_length(struct acpi_pci_root *root) +{ + if (is_cxl(root)) + return sizeof(u32) * OSC_CXL_CAPABILITY_DWORDS; + return sizeof(u32) * OSC_PCI_CAPABILITY_DWORDS; +} -static acpi_status acpi_pci_run_osc(acpi_handle handle, +static acpi_status acpi_pci_run_osc(struct acpi_pci_root *root, const u32 *capbuf, u32 *retval) { struct acpi_osc_context context = { - .uuid_str = pci_osc_uuid_str, + .uuid_str = to_uuid(root), .rev = 1, - .cap.length = 12, + .cap.length = cap_length(root), .cap.pointer = (void *)capbuf, }; acpi_status status; - status = acpi_run_osc(handle, &context); + status = acpi_run_osc(root->device->handle, &context); if (ACPI_SUCCESS(status)) { *retval = acpi_osc_ctx_get_pci_control(&context); kfree(context.ret.pointer); @@ -194,7 +219,7 @@ static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 *control) { acpi_status status; - u32 result, capbuf[3]; + u32 result, capbuf[OSC_CXL_CAPABILITY_DWORDS]; support |= root->osc_support_set; @@ -202,10 +227,18 @@ static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, capbuf[OSC_SUPPORT_DWORD] = support; capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set; - status = acpi_pci_run_osc(root->device->handle, capbuf, &result); +retry: + status = acpi_pci_run_osc(root, capbuf, &result); if (ACPI_SUCCESS(status)) { root->osc_support_set = support; *control = result; + } else if (is_cxl(root)) { + /* + * CXL _OSC is optional on CXL 1.1 hosts. Fall back to PCIe _OSC + * upon any failure using CXL _OSC. + */ + root->bridge_type = ACPI_BRIDGE_TYPE_PCIE; + goto retry; } return status; } @@ -336,7 +369,7 @@ static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 s u32 req = OSC_PCI_EXPRESS_CAPABILITY_CONTROL; struct acpi_pci_root *root; acpi_status status; - u32 ctrl, capbuf[3]; + u32 ctrl, capbuf[OSC_CXL_CAPABILITY_DWORDS]; if (!mask) return AE_BAD_PARAMETER; @@ -373,7 +406,7 @@ static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 s capbuf[OSC_QUERY_DWORD] = 0; capbuf[OSC_SUPPORT_DWORD] = root->osc_support_set; capbuf[OSC_CONTROL_DWORD] = ctrl; - status = acpi_pci_run_osc(handle, capbuf, mask); + status = acpi_pci_run_osc(root, capbuf, mask); if (ACPI_FAILURE(status)) return status; @@ -452,8 +485,7 @@ static bool os_control_query_checks(struct acpi_pci_root *root, u32 support) return true; } -static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm, - bool is_pcie) +static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm) { u32 support, control = 0, requested = 0; acpi_status status; @@ -504,7 +536,7 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm, *no_aspm = 1; /* _OSC is optional for PCI host bridges */ - if ((status == AE_NOT_FOUND) && !is_pcie) + if (status == AE_NOT_FOUND && !is_pcie(root)) return; if (control) { @@ -527,7 +559,7 @@ static int acpi_pci_root_add(struct acpi_device *device, acpi_handle handle = device->handle; int no_aspm = 0; bool hotadd = system_state == SYSTEM_RUNNING; - bool is_pcie; + const char *acpi_hid; root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL); if (!root) @@ -585,8 +617,15 @@ static int acpi_pci_root_add(struct acpi_device *device, root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle); - is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0; - negotiate_os_control(root, &no_aspm, is_pcie); + acpi_hid = acpi_device_hid(root->device); + if (strcmp(acpi_hid, "PNP0A08") == 0) + root->bridge_type = ACPI_BRIDGE_TYPE_PCIE; + else if (strcmp(acpi_hid, "ACPI0016") == 0) + root->bridge_type = ACPI_BRIDGE_TYPE_CXL; + else + dev_dbg(&device->dev, "Assuming non-PCIe host bridge\n"); + + negotiate_os_control(root, &no_aspm); /* * TBD: Need PCI interface for enumeration/configuration of roots. diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index c4b78c21d793..305ebf2a3fa7 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -582,10 +582,16 @@ int unregister_acpi_bus_type(struct acpi_bus_type *); int acpi_bind_one(struct device *dev, struct acpi_device *adev); int acpi_unbind_one(struct device *dev); +enum acpi_bridge_type { + ACPI_BRIDGE_TYPE_PCIE = 1, + ACPI_BRIDGE_TYPE_CXL, +}; + struct acpi_pci_root { struct acpi_device * device; struct pci_bus *bus; u16 segment; + int bridge_type; struct resource secondary; /* downstream bus range */ u32 osc_support_set; /* _OSC state of support bits */ diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 04e5a038dd57..82d91d9ccce5 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -550,6 +550,10 @@ struct acpi_osc_context { acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context); +/* Number of _OSC capability DWORDS depends on bridge type */ +#define OSC_PCI_CAPABILITY_DWORDS 3 +#define OSC_CXL_CAPABILITY_DWORDS 5 + /* Indexes into _OSC Capabilities Buffer (DWORDs 2 & 3 are device-specific) */ #define OSC_QUERY_DWORD 0 /* DWORD 1 */ #define OSC_SUPPORT_DWORD 1 /* DWORD 2 */ |