diff options
| -rw-r--r-- | drivers/pci/hotplug/acpi_pcihp.c | 36 | ||||
| -rw-r--r-- | drivers/pci/hotplug/shpchp_core.c | 21 | ||||
| -rw-r--r-- | drivers/pci/pci-acpi.c | 19 | ||||
| -rw-r--r-- | include/linux/pci.h | 1 |
4 files changed, 42 insertions, 35 deletions
diff --git a/drivers/pci/hotplug/acpi_pcihp.c b/drivers/pci/hotplug/acpi_pcihp.c index 5bd6c1573295..6b7c1ed58e7e 100644 --- a/drivers/pci/hotplug/acpi_pcihp.c +++ b/drivers/pci/hotplug/acpi_pcihp.c @@ -74,20 +74,6 @@ int acpi_get_hp_hw_control_from_firmware(struct pci_dev *pdev) struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL }; /* - * Per PCI firmware specification, we should run the ACPI _OSC - * method to get control of hotplug hardware before using it. If - * an _OSC is missing, we look for an OSHP to do the same thing. - * To handle different BIOS behavior, we look for _OSC on a root - * bridge preferentially (according to PCI fw spec). Later for - * OSHP within the scope of the hotplug controller and its parents, - * up to the host bridge under which this controller exists. - */ - if (shpchp_is_native(pdev)) - return 0; - - /* If _OSC exists, we should not evaluate OSHP */ - - /* * If there's no ACPI host bridge (i.e., ACPI support is compiled * into the kernel but the hardware platform doesn't support ACPI), * there's nothing to do here. @@ -97,9 +83,25 @@ int acpi_get_hp_hw_control_from_firmware(struct pci_dev *pdev) if (!root) return 0; - if (root->osc_support_set) - goto no_control; + /* + * If _OSC exists, it determines whether we're allowed to manage + * the SHPC. We executed it while enumerating the host bridge. + */ + if (root->osc_support_set) { + if (host->native_shpc_hotplug) + return 0; + return -ENODEV; + } + /* + * In the absence of _OSC, we're always allowed to manage the SHPC. + * However, if an OSHP method is present, we must execute it so the + * firmware can transfer control to the OS, e.g., direct interrupts + * to the OS instead of to the firmware. + * + * N.B. The PCI Firmware Spec (r3.2, sec 4.8) does not endorse + * searching up the ACPI hierarchy, so the loops below are suspect. + */ handle = ACPI_HANDLE(&pdev->dev); if (!handle) { /* @@ -128,7 +130,7 @@ int acpi_get_hp_hw_control_from_firmware(struct pci_dev *pdev) if (ACPI_FAILURE(status)) break; } -no_control: + pci_info(pdev, "Cannot get control of SHPC hotplug\n"); kfree(string.pointer); return -ENODEV; diff --git a/drivers/pci/hotplug/shpchp_core.c b/drivers/pci/hotplug/shpchp_core.c index e91be287f292..8e3c6ce12f31 100644 --- a/drivers/pci/hotplug/shpchp_core.c +++ b/drivers/pci/hotplug/shpchp_core.c @@ -270,11 +270,30 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) return 0; } +static bool shpc_capable(struct pci_dev *bridge) +{ + /* + * It is assumed that AMD GOLAM chips support SHPC but they do not + * have SHPC capability. + */ + if (bridge->vendor == PCI_VENDOR_ID_AMD && + bridge->device == PCI_DEVICE_ID_AMD_GOLAM_7450) + return true; + + if (pci_find_capability(bridge, PCI_CAP_ID_SHPC)) + return true; + + return false; +} + static int shpc_probe(struct pci_dev *pdev, const struct pci_device_id *ent) { int rc; struct controller *ctrl; + if (!shpc_capable(pdev)) + return -ENODEV; + if (acpi_get_hp_hw_control_from_firmware(pdev)) return -ENODEV; @@ -303,6 +322,7 @@ static int shpc_probe(struct pci_dev *pdev, const struct pci_device_id *ent) if (rc) goto err_cleanup_slots; + pdev->shpc_managed = 1; return 0; err_cleanup_slots: @@ -319,6 +339,7 @@ static void shpc_remove(struct pci_dev *dev) { struct controller *ctrl = pci_get_drvdata(dev); + dev->shpc_managed = 0; shpchp_remove_ctrl_files(ctrl); ctrl->hpc_ops->release_ctlr(ctrl); kfree(ctrl); diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index 65113b6eed14..5100fd2d5a75 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -403,24 +403,7 @@ bool pciehp_is_native(struct pci_dev *bridge) */ bool shpchp_is_native(struct pci_dev *bridge) { - const struct pci_host_bridge *host; - - if (!IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC)) - return false; - - /* - * It is assumed that AMD GOLAM chips support SHPC but they do not - * have SHPC capability. - */ - if (bridge->vendor == PCI_VENDOR_ID_AMD && - bridge->device == PCI_DEVICE_ID_AMD_GOLAM_7450) - return true; - - if (!pci_find_capability(bridge, PCI_CAP_ID_SHPC)) - return false; - - host = pci_find_host_bridge(bridge->bus); - return host->native_shpc_hotplug; + return bridge->shpc_managed; } /** diff --git a/include/linux/pci.h b/include/linux/pci.h index 340029b2fb38..f776a1cce120 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -388,6 +388,7 @@ struct pci_dev { unsigned int is_virtfn:1; unsigned int reset_fn:1; unsigned int is_hotplug_bridge:1; + unsigned int shpc_managed:1; /* SHPC owned by shpchp */ unsigned int is_thunderbolt:1; /* Thunderbolt controller */ unsigned int __aer_firmware_first_valid:1; unsigned int __aer_firmware_first:1; |