[11/27] PNP: work around Dell 1536/1546 BIOS MMCONFIG bug that breaks USB

Greg KH
2012-01-23T23:45:07Z

From: Bjorn Helgaas <bhelgaas@google.com>

commit eb31aae8cb5eb54e234ed2d857ddac868195d911 upstream.

Some Dell BIOSes have MCFG tables that don't report the entire
MMCONFIG area claimed by the chipset. If we move PCI devices into
that claimed-but-unreported area, they don't work.

This quirk reads the AMD MMCONFIG MSRs and adds PNP0C01 resources as
needed to cover the entire area.

Example problem scenario:

BIOS-e820: 00000000cfec5400 - 00000000d4000000 (reserved)
Fam 10h mmconf [d0000000, dfffffff]
PCI: MMCONFIG for domain 0000 [bus 00-3f] at [mem 0xd0000000-0xd3ffffff] (base 0xd0000000)
pnp 00:0c: [mem 0xd0000000-0xd3ffffff]
pci 0000:00:12.0: reg 10: [mem 0xffb00000-0xffb00fff]
pci 0000:00:12.0: no compatible bridge window for [mem 0xffb00000-0xffb00fff]
pci 0000:00:12.0: BAR 0: assigned [mem 0xd4000000-0xd40000ff]

Reported-by: Lisa Salimbas <lisa.salimbas@canonical.com>
Reported-by: <thuban@singularity.fr>
Tested-by: dann frazier <dann.frazier@canonical.com>
References: https://bugzilla.kernel.org/show_bug.cgi?id=31602
References: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/647043
References: https://bugzilla.redhat.com/show_bug.cgi?id=770308
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/pnp/quirks.c | 42 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 42 insertions(+)

--- a/drivers/pnp/quirks.c
+++ b/drivers/pnp/quirks.c
@@ -300,6 +300,45 @@ static void quirk_system_pci_resources(s
}
}

+#ifdef CONFIG_AMD_NB
+
+#include <asm/amd_nb.h>
+
+static void quirk_amd_mmconfig_area(struct pnp_dev *dev)
+{
+ resource_size_t start, end;
+ struct pnp_resource *pnp_res;
+ struct resource *res;
+ struct resource mmconfig_res, *mmconfig;
+
+ mmconfig = amd_get_mmconfig_range(&mmconfig_res);
+ if (!mmconfig)
+ return;
+
+ list_for_each_entry(pnp_res, &dev->resources, list) {
+ res = &pnp_res->res;
+ if (res->end < mmconfig->start || res->start > mmconfig->end ||
+ (res->start == mmconfig->start && res->end == mmconfig->end))
+ continue;
+
+ dev_info(&dev->dev, FW_BUG
+ "%pR covers only part of AMD MMCONFIG area %pR; adding more reservations\n",
+ res, mmconfig);
+ if (mmconfig->start < res->start) {
+ start = mmconfig->start;
+ end = res->start - 1;
+ pnp_add_mem_resource(dev, start, end, 0);
+ }
+ if (mmconfig->end > res->end) {
+ start = res->end + 1;
+ end = mmconfig->end;
+ pnp_add_mem_resource(dev, start, end, 0);
+ }
+ break;
+ }
+}
+#endif
+
/*
* PnP Quirks
* Cards or devices that need some tweaking due to incomplete resource info
@@ -327,6 +366,9 @@ static struct pnp_fixup pnp_fixups[] = {
/* PnP resources that might overlap PCI BARs */
{"PNP0c01", quirk_system_pci_resources},
{"PNP0c02", quirk_system_pci_resources},
+#ifdef CONFIG_AMD_NB
+ {"PNP0c01", quirk_amd_mmconfig_area},
+#endif
{""}
};