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;