PNP: disable PNP motherboard resources that overlap PCI BARs
[sfrench/cifs-2.6.git] / drivers / pnp / quirks.c
index e903b8c2b1fa5e200e2140d609deb643ea49d195..37993206ae5dd149d98672345ef5d16c6c21743c 100644 (file)
@@ -108,6 +108,77 @@ static void quirk_sb16audio_resources(struct pnp_dev *dev)
                       "pnp: SB audio device quirk - increasing port range\n");
 }
 
+
+#include <linux/pci.h>
+
+static void quirk_system_pci_resources(struct pnp_dev *dev)
+{
+       struct pci_dev *pdev = NULL;
+       resource_size_t pnp_start, pnp_end, pci_start, pci_end;
+       int i, j;
+
+       /*
+        * Some BIOSes have PNP motherboard devices with resources that
+        * partially overlap PCI BARs.  The PNP system driver claims these
+        * motherboard resources, which prevents the normal PCI driver from
+        * requesting them later.
+        *
+        * This patch disables the PNP resources that conflict with PCI BARs
+        * so they won't be claimed by the PNP system driver.
+        */
+       for_each_pci_dev(pdev) {
+               for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
+                       if (!(pci_resource_flags(pdev, i) & IORESOURCE_MEM) ||
+                           pci_resource_len(pdev, i) == 0)
+                               continue;
+
+                       pci_start = pci_resource_start(pdev, i);
+                       pci_end = pci_resource_end(pdev, i);
+                       for (j = 0; j < PNP_MAX_MEM; j++) {
+                               if (!pnp_mem_valid(dev, j) ||
+                                   pnp_mem_len(dev, j) == 0)
+                                       continue;
+
+                               pnp_start = pnp_mem_start(dev, j);
+                               pnp_end = pnp_mem_end(dev, j);
+
+                               /*
+                                * If the PNP region doesn't overlap the PCI
+                                * region at all, there's no problem.
+                                */
+                               if (pnp_end < pci_start || pnp_start > pci_end)
+                                       continue;
+
+                               /*
+                                * If the PNP region completely encloses (or is
+                                * at least as large as) the PCI region, that's
+                                * also OK.  For example, this happens when the
+                                * PNP device describes a bridge with PCI
+                                * behind it.
+                                */
+                               if (pnp_start <= pci_start &&
+                                   pnp_end >= pci_end)
+                                       continue;
+
+                               /*
+                                * Otherwise, the PNP region overlaps *part* of
+                                * the PCI region, and that might prevent a PCI
+                                * driver from requesting its resources.
+                                */
+                               dev_warn(&dev->dev, "mem resource "
+                                       "(0x%llx-0x%llx) overlaps %s BAR %d "
+                                       "(0x%llx-0x%llx), disabling\n",
+                                       (unsigned long long) pnp_start,
+                                       (unsigned long long) pnp_end,
+                                       pci_name(pdev), i,
+                                       (unsigned long long) pci_start,
+                                       (unsigned long long) pci_end);
+                               pnp_mem_flags(dev, j) = 0;
+                       }
+               }
+       }
+}
+
 /*
  *  PnP Quirks
  *  Cards or devices that need some tweaking due to incomplete resource info
@@ -128,6 +199,8 @@ static struct pnp_fixup pnp_fixups[] = {
        {"CTL0043", quirk_sb16audio_resources},
        {"CTL0044", quirk_sb16audio_resources},
        {"CTL0045", quirk_sb16audio_resources},
+       {"PNP0c01", quirk_system_pci_resources},
+       {"PNP0c02", quirk_system_pci_resources},
        {""}
 };