Re: Regression with commit f9cde5f in 2.6.30-gitX

[Yinghai Lu <yhlu.kernel@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 804 bytes --]

On Wed, Jun 24, 2009 at 3:11 PM, Yinghai Lu<yhlu.kernel@gmail.com> wrote:
> On Wed, Jun 24, 2009 at 3:04 PM, Larry Finger<Larry.Finger@lwfinger.net> wrote:
>> Yinghai Lu wrote:
>> node 0 link 0: mmio [a0000, bffff]
>> node 0 link 0: mmio [c0000000, dfffffff]
>> node 0 link 0: mmio [e0000000, efffffff]
>> node 0 link 0: mmio [f0000000, fe0bffff]
>> bus: [00,ff] on node 0 link 0
>> bus: 00 index 0 io port: [0, ffff]
>> bus: 00 index 1 mmio: [a0000, bffff]
>> bus: 00 index 2 mmio: [c0000000, fcffffffff]
>
> that is read from pci config.
>
> and only one HT chain is there. so there is no point to use _CRS for them.
>
> please let me check if we could could have patch to deselect that.
>

please try the attached patches.

applying sequence:
fix_crs.patch
use_pci_crs_early.patch

only_one.patch

YH

[-- Attachment #2: fix_crs.patch --]
[-- Type: text/x-diff, Size: 1982 bytes --]

[PATCH] x86/pci: fix boundary checking

don't touch info->res_num if we are out of space

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 arch/x86/pci/acpi.c |   27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

Index: linux-2.6/arch/x86/pci/acpi.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/acpi.c
+++ linux-2.6/arch/x86/pci/acpi.c
@@ -68,6 +68,10 @@ setup_resource(struct acpi_resource *acp
 	unsigned long flags;
 	struct resource *root;
 	int max_root_bus_resources = PCI_BUS_NUM_RESOURCES;
+	u64 start, end;
+
+	if (bus_has_transparent_bridge(info->bus))
+		max_root_bus_resources -= 3;
 
 	status = resource_to_addr(acpi_res, &addr);
 	if (!ACPI_SUCCESS(status))
@@ -84,25 +88,24 @@ setup_resource(struct acpi_resource *acp
 	} else
 		return AE_OK;
 
-	res = &info->res[info->res_num];
-	res->name = info->name;
-	res->flags = flags;
-	res->start = addr.minimum + addr.translation_offset;
-	res->end = res->start + addr.address_length - 1;
-	res->child = NULL;
-
-	if (bus_has_transparent_bridge(info->bus))
-		max_root_bus_resources -= 3;
+	start = addr.minimum + addr.translation_offset;
+	end = start + addr.address_length - 1;
 	if (info->res_num >= max_root_bus_resources) {
 		printk(KERN_WARNING "PCI: Failed to allocate 0x%lx-0x%lx "
 			"from %s for %s due to _CRS returning more than "
-			"%d resource descriptors\n", (unsigned long) res->start,
-			(unsigned long) res->end, root->name, info->name,
+			"%d resource descriptors\n", (unsigned long) start,
+			(unsigned long) end, root->name, info->name,
 			max_root_bus_resources);
-		info->res_num++;
 		return AE_OK;
 	}
 
+	res = &info->res[info->res_num];
+	res->name = info->name;
+	res->flags = flags;
+	res->start = start;
+	res->end = end;
+	res->child = NULL;
+
 	if (insert_resource(root, res)) {
 		printk(KERN_ERR "PCI: Failed to allocate 0x%lx-0x%lx "
 			"from %s for %s\n", (unsigned long) res->start,

[-- Attachment #3: use_pci_crs_early.patch --]
[-- Type: text/x-diff, Size: 2982 bytes --]

[PATCH] x86/pci: get root CRS before scan childs -v2

so we could remove adjust_transparent_bridge_resources..

and give x86_pci_root_bus_res_quirks chance when _CRS is not used or
not there.

v2: add print out if pci conf reading for res is used for root

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 arch/x86/pci/acpi.c    |   32 +++++++++-----------------------
 arch/x86/pci/amd_bus.c |    8 ++++++--
 2 files changed, 15 insertions(+), 25 deletions(-)

Index: linux-2.6/arch/x86/pci/acpi.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/acpi.c
+++ linux-2.6/arch/x86/pci/acpi.c
@@ -118,23 +118,6 @@ setup_resource(struct acpi_resource *acp
 }
 
 static void
-adjust_transparent_bridge_resources(struct pci_bus *bus)
-{
-	struct pci_dev *dev;
-
-	list_for_each_entry(dev, &bus->devices, bus_list) {
-		int i;
-		u16 class = dev->class >> 8;
-
-		if (class == PCI_CLASS_BRIDGE_PCI && dev->transparent) {
-			for(i = 3; i < PCI_BUS_NUM_RESOURCES; i++)
-				dev->subordinate->resource[i] =
-						dev->bus->resource[i - 3];
-		}
-	}
-}
-
-static void
 get_current_resources(struct acpi_device *device, int busnum,
 			int domain, struct pci_bus *bus)
 {
@@ -161,8 +144,6 @@ get_current_resources(struct acpi_device
 	info.res_num = 0;
 	acpi_walk_resources(device->handle, METHOD_NAME__CRS, setup_resource,
 				&info);
-	if (info.res_num)
-		adjust_transparent_bridge_resources(bus);
 
 	return;
 
@@ -225,8 +206,15 @@ struct pci_bus * __devinit pci_acpi_scan
 		 */
 		memcpy(bus->sysdata, sd, sizeof(*sd));
 		kfree(sd);
-	} else
-		bus = pci_scan_bus_parented(NULL, busnum, &pci_root_ops, sd);
+	} else {
+		bus = pci_create_bus(NULL, busnum, &pci_root_ops, sd);
+		if (bus) {
+			if (!(pci_probe & PCI_NO_ROOT_CRS))
+				get_current_resources(device, busnum, domain,
+							bus);
+			bus->subordinate = pci_scan_child_bus(bus);
+		}
+	}
 
 	if (!bus)
 		kfree(sd);
@@ -241,8 +229,6 @@ struct pci_bus * __devinit pci_acpi_scan
 #endif
 	}
 
-	if (bus && !(pci_probe & PCI_NO_ROOT_CRS))
-		get_current_resources(device, busnum, domain, bus);
 	return bus;
 }
 
Index: linux-2.6/arch/x86/pci/amd_bus.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/amd_bus.c
+++ linux-2.6/arch/x86/pci/amd_bus.c
@@ -100,8 +100,9 @@ void x86_pci_root_bus_res_quirks(struct
 	int j;
 	struct pci_root_info *info;
 
-	/* don't go for it if _CRS is used */
-	if (!(pci_probe & PCI_NO_ROOT_CRS))
+       /* don't go for it if _CRS is used already */
+	if (b->resource[0] != &ioport_resource ||
+	    b->resource[1] != &iomem_resource)
 		return;
 
 	/* if only one root bus, don't need to anything */
@@ -116,6 +117,9 @@ void x86_pci_root_bus_res_quirks(struct
 	if (i == pci_root_num)
 		return;
 
+	printk(KERN_DEBUG "PCI: peer root bus %02x res updated from pci conf\n",
+			b->number);
+
 	info = &pci_root_info[i];
 	for (j = 0; j < info->res_num; j++) {
 		struct resource *res;

[-- Attachment #4: only_one.patch --]
[-- Type: text/x-diff, Size: 650 bytes --]

[PATCH] x86/pci: don't use crs for root if we only have one root bus

for AMD system, when only one PCI root, just set PCI_NO_ROOT_CRS for it

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 arch/x86/pci/amd_bus.c |    4 ++++
 1 file changed, 4 insertions(+)

Index: linux-2.6/arch/x86/pci/amd_bus.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/amd_bus.c
+++ linux-2.6/arch/x86/pci/amd_bus.c
@@ -561,6 +561,10 @@ static int __init early_fill_mp_bus_info
 		}
 	}
 
+	/* don't use _CRS if we only have one root */
+	if (pci_root_num <= 1)
+		pci_probe |= PCI_NO_ROOT_CRS;
+
 	return 0;
 }