Imported linux-2.6.27.39 suse/xen patches.

[ipfire-2.x.git] / src / patches / suse-2.6.27.39 / patches.drivers / acpi-pci-call-_osc-support-during-root-bridge-discovery.patch

From 990a7ac5645883a833a11b900bb6f25b65dea65b Mon Sep 17 00:00:00 2001
From: Andrew Patterson <andrew.patterson@hp.com>
Date: Mon, 10 Nov 2008 15:30:45 -0700
Subject: ACPI/PCI: call _OSC support during root bridge discovery
Patch-mainline: 2.6.29
References: bnc#438941

Add pci_acpi_osc_support() and call it when a PCI bridge is added.  This
allows us to avoid having every individual PCI root bridge driver call
_OSC support for every root bridge in their probe functions, a
significant savings in boot time.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/acpi/pci_root.c  |    9 +++++++++
 drivers/pci/pci-acpi.c   |   27 ++++++++++++++++++++-------
 include/linux/pci-acpi.h |    1 +
 3 files changed, 30 insertions(+), 7 deletions(-)

--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -31,6 +31,7 @@
 #include <linux/spinlock.h>
 #include <linux/pm.h>
 #include <linux/pci.h>
+#include <linux/pci-acpi.h>
 #include <linux/acpi.h>
 #include <acpi/acpi_bus.h>
 #include <acpi/acpi_drivers.h>
@@ -193,6 +194,7 @@ static int __devinit acpi_pci_root_add(s
 	unsigned long long value = 0;
 	acpi_handle handle = NULL;
 	struct acpi_device *child;
+	u32 flags;
 
 
 	if (!device)
@@ -210,6 +212,13 @@ static int __devinit acpi_pci_root_add(s
 
 	device->ops.bind = acpi_pci_bind;
 
+	/*
+	 * All supported architectures that use ACPI have support for
+	 * PCI domains, so we indicate this in _OSC support capabilities.
+	 */
+	flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
+	pci_acpi_osc_support(device->handle, flags);
+
 	/* 
 	 * Segment
 	 * -------
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -142,32 +142,45 @@ static acpi_status __acpi_query_osc(u32 
 	return status;
 }
 
-static acpi_status acpi_query_osc(acpi_handle handle,
-				  u32 level, void *context, void **retval)
+/*
+ * pci_acpi_osc_support: Invoke _OSC indicating support for the given feature
+ * @flags: Bitmask of flags to support
+ *
+ * See the ACPI spec for the definition of the flags
+ */
+int pci_acpi_osc_support(acpi_handle handle, u32 flags)
 {
 	acpi_status status;
-	struct acpi_osc_data *osc_data;
-	u32 flags = (unsigned long)context;
 	acpi_handle tmp;
+	struct acpi_osc_data *osc_data;
+	int rc = 0;
 
 	status = acpi_get_handle(handle, "_OSC", &tmp);
 	if (ACPI_FAILURE(status))
-		return status;
+		return -ENOTTY;
 
 	mutex_lock(&pci_acpi_lock);
 	osc_data = acpi_get_osc_data(handle);
 	if (!osc_data) {
 		printk(KERN_ERR "acpi osc data array is full\n");
-		status = AE_ERROR;
+		rc = -ENOMEM;
 		goto out;
 	}
 
 	status = __acpi_query_osc(flags, osc_data);
 out:
 	mutex_unlock(&pci_acpi_lock);
-	return status;
+	return rc;
+}
+
+static acpi_status acpi_query_osc(acpi_handle handle, u32 level,
+				  void *context, void **retval)
+{
+	pci_acpi_osc_support(handle, (unsigned long)context);
+	return AE_OK;
 }
 
+
 /**
  * __pci_osc_support_set - register OS support to Firmware
  * @flags: OS support bits
--- a/include/linux/pci-acpi.h
+++ b/include/linux/pci-acpi.h
@@ -51,6 +51,7 @@
 #ifdef CONFIG_ACPI
 extern acpi_status pci_osc_control_set(acpi_handle handle, u32 flags);
 extern acpi_status __pci_osc_support_set(u32 flags, const char *hid);
+int pci_acpi_osc_support(acpi_handle handle, u32 flags);
 static inline acpi_status pci_osc_support_set(u32 flags)
 {
 	return __pci_osc_support_set(flags, PCI_ROOT_HID_STRING);