diff options
Diffstat (limited to 'drivers/pci/pcie/edr.c')
| -rw-r--r-- | drivers/pci/pcie/edr.c | 28 |
1 files changed, 17 insertions, 11 deletions
diff --git a/drivers/pci/pcie/edr.c b/drivers/pci/pcie/edr.c index 5f4914d313..e86298dbbc 100644 --- a/drivers/pci/pcie/edr.c +++ b/drivers/pci/pcie/edr.c @@ -32,10 +32,10 @@ static int acpi_enable_dpc(struct pci_dev *pdev) int status = 0; /* - * Behavior when calling unsupported _DSM functions is undefined, - * so check whether EDR_PORT_DPC_ENABLE_DSM is supported. + * Per PCI Firmware r3.3, sec 4.6.12, EDR_PORT_DPC_ENABLE_DSM is + * optional. Return success if it's not implemented. */ - if (!acpi_check_dsm(adev->handle, &pci_acpi_dsm_guid, 5, + if (!acpi_check_dsm(adev->handle, &pci_acpi_dsm_guid, 6, 1ULL << EDR_PORT_DPC_ENABLE_DSM)) return 0; @@ -46,12 +46,7 @@ static int acpi_enable_dpc(struct pci_dev *pdev) argv4.package.count = 1; argv4.package.elements = &req; - /* - * Per Downstream Port Containment Related Enhancements ECN to PCI - * Firmware Specification r3.2, sec 4.6.12, EDR_PORT_DPC_ENABLE_DSM is - * optional. Return success if it's not implemented. - */ - obj = acpi_evaluate_dsm(adev->handle, &pci_acpi_dsm_guid, 5, + obj = acpi_evaluate_dsm(adev->handle, &pci_acpi_dsm_guid, 6, EDR_PORT_DPC_ENABLE_DSM, &argv4); if (!obj) return 0; @@ -85,8 +80,9 @@ static struct pci_dev *acpi_dpc_port_get(struct pci_dev *pdev) u16 port; /* - * Behavior when calling unsupported _DSM functions is undefined, - * so check whether EDR_PORT_DPC_ENABLE_DSM is supported. + * If EDR_PORT_LOCATE_DSM is not implemented under the target of + * EDR, the target is the port that experienced the containment + * event (PCI Firmware r3.3, sec 4.6.13). */ if (!acpi_check_dsm(adev->handle, &pci_acpi_dsm_guid, 5, 1ULL << EDR_PORT_LOCATE_DSM)) @@ -104,6 +100,16 @@ static struct pci_dev *acpi_dpc_port_get(struct pci_dev *pdev) } /* + * Bit 31 represents the success/failure of the operation. If bit + * 31 is set, the operation failed. + */ + if (obj->integer.value & BIT(31)) { + ACPI_FREE(obj); + pci_err(pdev, "Locate Port _DSM failed\n"); + return NULL; + } + + /* * Firmware returns DPC port BDF details in following format: * 15:8 = bus * 7:3 = device |