PCI/ACPI: Request _OSC control once for each root bridge (v3)

Move the evaluation of acpi_pci_osc_control_set() (to request control of
PCI Express native features) into acpi_pci_root_add() to avoid calling
it many times for the same root complex with the same arguments.
Additionally, check if all of the requisite _OSC support bits are set
before calling acpi_pci_osc_control_set() for a given root complex.

References: https://bugzilla.kernel.org/show_bug.cgi?id=20232
Reported-by: Ozan Caglayan <ozan@pardus.org.tr>
Tested-by: Ozan Caglayan <ozan@pardus.org.tr>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

2 files changed, 44 insertions, 13 deletions

diff --git a/drivers/acpi/apei/hest.c b/drivers/acpi/apei/hest.c
index daa7bc63f1d4..4ee58e72b730 100644
--- a/drivers/acpi/apei/hest.c
+++ b/drivers/acpi/apei/hest.c
@@ -195,24 +195,24 @@ static int __init setup_hest_disable(char *str)
 
 __setup("hest_disable", setup_hest_disable);
 
-static int __init hest_init(void)
+void __init acpi_hest_init(void)
 {
         acpi_status status;
         int rc = -ENODEV;
         unsigned int ghes_count = 0;
 
         if (acpi_disabled)
-                goto err;
+                return;
 
         if (hest_disable) {
-                pr_info(HEST_PFX "HEST tabling parsing is disabled.\n");
-                goto err;
+                pr_info(HEST_PFX "Table parsing disabled.\n");
+                return;
         }
 
         status = acpi_get_table(ACPI_SIG_HEST, 0,
                                 (struct acpi_table_header **)&hest_tab);
         if (status == AE_NOT_FOUND) {
-                pr_info(HEST_PFX "Table is not found!\n");
+                pr_info(HEST_PFX "Table not found.\n");
                 goto err;
         } else if (ACPI_FAILURE(status)) {
                 const char *msg = acpi_format_exception(status);
@@ -226,15 +226,11 @@ static int __init hest_init(void)
                 goto err;
 
         rc = hest_ghes_dev_register(ghes_count);
-        if (rc)
-                goto err;
-
-        pr_info(HEST_PFX "HEST table parsing is initialized.\n");
+        if (!rc) {
+                pr_info(HEST_PFX "Table parsing has been initialized.\n");
+                return;
+        }
 
-        return 0;
 err:
         hest_disable = 1;
-        return rc;
 }
-
-subsys_initcall(hest_init);
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 96668ad09622..d9766797cd98 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -36,6 +36,7 @@
 #include <linux/slab.h>
 #include <acpi/acpi_bus.h>
 #include <acpi/acpi_drivers.h>
+#include <acpi/apei.h>
 
 #define PREFIX "ACPI: "
 
@@ -47,6 +48,11 @@ static int acpi_pci_root_add(struct acpi_device *device);
 static int acpi_pci_root_remove(struct acpi_device *device, int type);
 static int acpi_pci_root_start(struct acpi_device *device);
 
+#define ACPI_PCIE_REQ_SUPPORT (OSC_EXT_PCI_CONFIG_SUPPORT \
+                                | OSC_ACTIVE_STATE_PWR_SUPPORT \
+                                | OSC_CLOCK_PWR_CAPABILITY_SUPPORT \
+                                | OSC_MSI_SUPPORT)
+
 static const struct acpi_device_id root_device_ids[] = {
         {"PNP0A03", 0},
         {"", 0},
@@ -566,6 +572,33 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
         if (flags != base_flags)
                 acpi_pci_osc_support(root, flags);
 
+        if (!pcie_ports_disabled
+            && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) {
+                flags = OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL
+                        | OSC_PCI_EXPRESS_NATIVE_HP_CONTROL
+                        | OSC_PCI_EXPRESS_PME_CONTROL;
+
+                if (pci_aer_available()) {
+                        if (aer_acpi_firmware_first())
+                                dev_dbg(root->bus->bridge,
+                                        "PCIe errors handled by BIOS.\n");
+                        else
+                                flags |= OSC_PCI_EXPRESS_AER_CONTROL;
+                }
+
+                dev_info(root->bus->bridge,
+                        "Requesting ACPI _OSC control (0x%02x)\n", flags);
+
+                status = acpi_pci_osc_control_set(device->handle, &flags,
+                                        OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
+                if (ACPI_SUCCESS(status))
+                        dev_info(root->bus->bridge,
+                                "ACPI _OSC control (0x%02x) granted\n", flags);
+                else
+                        dev_dbg(root->bus->bridge,
+                                "ACPI _OSC request failed (code %d)\n", status);
+        }
+
         pci_acpi_add_bus_pm_notifier(device, root->bus);
         if (device->wakeup.flags.run_wake)
                 device_set_run_wake(root->bus->bridge, true);
@@ -603,6 +636,8 @@ static int __init acpi_pci_root_init(void)
         if (acpi_pci_disabled)
                 return 0;
 
+        acpi_hest_init();
+
         pci_acpi_crs_quirks();
         if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
                 return -ENODEV;