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

["Rafael J. Wysocki" <rjw@sisk.pl>]

From: Rafael J. Wysocki <rjw@sisk.pl>

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.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---

Hi,

The previous versions were buggy, because they assumed that hest_init() would
be called before acpi_pci_root_init(), but that need not be the case.  This
version fixes the problem (hopefully, it's the last update of this patch).

Thanks,
Rafael

---
 drivers/acpi/apei/hest.c        |   22 +++++++++-------------
 drivers/acpi/pci_root.c         |   35 +++++++++++++++++++++++++++++++++++
 drivers/pci/pci.h               |    8 --------
 drivers/pci/pcie/aer/aerdrv.c   |    1 +
 drivers/pci/pcie/aer/aerdrv.h   |    3 ---
 drivers/pci/pcie/portdrv.h      |    3 ---
 drivers/pci/pcie/portdrv_acpi.c |   23 ++++-------------------
 include/acpi/apei.h             |    6 ++++++
 include/linux/pci-acpi.h        |    6 ++++++
 include/linux/pci.h             |   11 +++++++++++
 10 files changed, 72 insertions(+), 46 deletions(-)

Index: linux-2.6/drivers/acpi/pci_root.c
===================================================================
--- linux-2.6.orig/drivers/acpi/pci_root.c
+++ linux-2.6/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
 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(s
 	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(voi
 	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;
Index: linux-2.6/drivers/pci/pcie/portdrv_acpi.c
===================================================================
--- linux-2.6.orig/drivers/pci/pcie/portdrv_acpi.c
+++ linux-2.6/drivers/pci/pcie/portdrv_acpi.c
@@ -33,7 +33,7 @@
  */
 int pcie_port_acpi_setup(struct pci_dev *port, int *srv_mask)
 {
-	acpi_status status;
+	struct acpi_pci_root *root;
 	acpi_handle handle;
 	u32 flags;
 
@@ -44,26 +44,11 @@ int pcie_port_acpi_setup(struct pci_dev
 	if (!handle)
 		return -EINVAL;
 
-	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(&port->dev, "PCIe errors handled by BIOS.\n");
-		else
-			flags |= OSC_PCI_EXPRESS_AER_CONTROL;
-	}
-
-	status = acpi_pci_osc_control_set(handle, &flags,
-					OSC_PCI_EXPRESS_CAP_STRUCTURE_CONTROL);
-	if (ACPI_FAILURE(status)) {
-		dev_dbg(&port->dev, "ACPI _OSC request failed (code %d)\n",
-			status);
+	root = acpi_pci_find_root(handle);
+	if (!root)
 		return -ENODEV;
-	}
 
-	dev_info(&port->dev, "ACPI _OSC control granted for 0x%02x\n", flags);
+	flags = root->osc_control_set;
 
 	*srv_mask = PCIE_PORT_SERVICE_VC;
 	if (flags & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL)
Index: linux-2.6/drivers/pci/pci.h
===================================================================
--- linux-2.6.orig/drivers/pci/pci.h
+++ linux-2.6/drivers/pci/pci.h
@@ -146,14 +146,6 @@ static inline void pci_no_msi(void) { }
 static inline void pci_msi_init_pci_dev(struct pci_dev *dev) { }
 #endif
 
-#ifdef CONFIG_PCIEAER
-void pci_no_aer(void);
-bool pci_aer_available(void);
-#else
-static inline void pci_no_aer(void) { }
-static inline bool pci_aer_available(void) { return false; }
-#endif
-
 static inline int pci_no_d1d2(struct pci_dev *dev)
 {
 	unsigned int parent_dstates = 0;
Index: linux-2.6/include/linux/pci.h
===================================================================
--- linux-2.6.orig/include/linux/pci.h
+++ linux-2.6/include/linux/pci.h
@@ -993,6 +993,9 @@ extern void pci_restore_msi_state(struct
 extern int pci_msi_enabled(void);
 #endif
 
+extern bool pcie_ports_disabled;
+extern bool pcie_ports_auto;
+
 #ifndef CONFIG_PCIEASPM
 static inline int pcie_aspm_enabled(void)
 {
@@ -1002,6 +1005,14 @@ static inline int pcie_aspm_enabled(void
 extern int pcie_aspm_enabled(void);
 #endif
 
+#ifdef CONFIG_PCIEAER
+void pci_no_aer(void);
+bool pci_aer_available(void);
+#else
+static inline void pci_no_aer(void) { }
+static inline bool pci_aer_available(void) { return false; }
+#endif
+
 #ifndef CONFIG_PCIE_ECRC
 static inline void pcie_set_ecrc_checking(struct pci_dev *dev)
 {
Index: linux-2.6/drivers/pci/pcie/aer/aerdrv.h
===================================================================
--- linux-2.6.orig/drivers/pci/pcie/aer/aerdrv.h
+++ linux-2.6/drivers/pci/pcie/aer/aerdrv.h
@@ -132,7 +132,6 @@ static inline int aer_osc_setup(struct p
 
 #ifdef CONFIG_ACPI_APEI
 extern int pcie_aer_get_firmware_first(struct pci_dev *pci_dev);
-extern bool aer_acpi_firmware_first(void);
 #else
 static inline int pcie_aer_get_firmware_first(struct pci_dev *pci_dev)
 {
@@ -140,8 +139,6 @@ static inline int pcie_aer_get_firmware_
 		return pci_dev->__aer_firmware_first;
 	return 0;
 }
-
-static inline bool aer_acpi_firmware_first(void) { return false; }
 #endif
 
 static inline void pcie_aer_force_firmware_first(struct pci_dev *pci_dev,
Index: linux-2.6/include/linux/pci-acpi.h
===================================================================
--- linux-2.6.orig/include/linux/pci-acpi.h
+++ linux-2.6/include/linux/pci-acpi.h
@@ -40,4 +40,10 @@ static inline acpi_handle acpi_find_root
 { return NULL; }
 #endif
 
+#ifdef CONFIG_ACPI_APEI
+extern bool aer_acpi_firmware_first(void);
+#else
+static inline bool aer_acpi_firmware_first(void) { return false; }
+#endif
+
 #endif	/* _PCI_ACPI_H_ */
Index: linux-2.6/drivers/pci/pcie/aer/aerdrv.c
===================================================================
--- linux-2.6.orig/drivers/pci/pcie/aer/aerdrv.c
+++ linux-2.6/drivers/pci/pcie/aer/aerdrv.c
@@ -17,6 +17,7 @@
 
 #include <linux/module.h>
 #include <linux/pci.h>
+#include <linux/pci-acpi.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
Index: linux-2.6/drivers/pci/pcie/portdrv.h
===================================================================
--- linux-2.6.orig/drivers/pci/pcie/portdrv.h
+++ linux-2.6/drivers/pci/pcie/portdrv.h
@@ -20,9 +20,6 @@
 
 #define get_descriptor_id(type, service) (((type - 4) << 4) | service)
 
-extern bool pcie_ports_disabled;
-extern bool pcie_ports_auto;
-
 extern struct bus_type pcie_port_bus_type;
 extern int pcie_port_device_register(struct pci_dev *dev);
 #ifdef CONFIG_PM
Index: linux-2.6/drivers/acpi/apei/hest.c
===================================================================
--- linux-2.6.orig/drivers/acpi/apei/hest.c
+++ linux-2.6/drivers/acpi/apei/hest.c
@@ -195,24 +195,24 @@ static int __init setup_hest_disable(cha
 
 __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);
Index: linux-2.6/include/acpi/apei.h
===================================================================
--- linux-2.6.orig/include/acpi/apei.h
+++ linux-2.6/include/acpi/apei.h
@@ -19,6 +19,12 @@
 extern int hest_disable;
 extern int erst_disable;
 
+#ifdef CONFIG_ACPI_APEI
+void __init acpi_hest_init(void);
+#else
+static inline void acpi_hest_init(void) { return; }
+#endif
+
 typedef int (*apei_hest_func_t)(struct acpi_hest_header *hest_hdr, void *data);
 int apei_hest_parse(apei_hest_func_t func, void *data);