[PATCH] pci bus resources, transparent bridges

Added PCI_BUS_NUM_RESOURCES as Ben suggested. Default value is 4
and can be overridden by arch (probably in asm/system.h).
pci_read_bridge_bases() and pci_assign_bus_resource() changed
accordingly. "for (i = 0 ; i < 4; i++)" in pci_add_new_bus() not
changed, as it's used _only_ for pci-pci and cardbus bridges.

diff --git a/arch/i386/pci/fixup.c b/arch/i386/pci/fixup.c
index 7165d0fd549ffd9a16ac8543a5a2cea658014e68..ca5e8fa1b9eb55efdbb24c19ee8752e63c14dcdb 100644 (file)
--- a/arch/i386/pci/fixup.c
+++ b/arch/i386/pci/fixup.c
@@ -166,6 +166,22 @@ static void __init pci_fixup_via_northbridge_bug(struct pci_dev *d)
        }
 }
 
+/*
+ * For some reasons Intel decided that certain parts of their
+ * 815, 845 and some other chipsets must look like PCI-to-PCI bridges
+ * while they are obviously not. The 82801 family (AA, AB, BAM/CAM,
+ * BA/CA/DB and E) PCI bridges are actually HUB-to-PCI ones, according
+ * to Intel terminology. These devices do forward all addresses from
+ * system to PCI bus no matter what are their window settings, so they are
+ * "transparent" (or subtractive decoding) from programmers point of view.
+ */
+static void __init pci_fixup_transparent_bridge(struct pci_dev *dev)
+{
+       if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI &&
+           (dev->device & 0xff00) == 0x2400)
+               dev->transparent = 1;
+}
+
 struct pci_fixup pcibios_fixups[] = {
        { PCI_FIXUP_HEADER,     PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_82451NX,    pci_fixup_i450nx },
        { PCI_FIXUP_HEADER,     PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_82454GX,    pci_fixup_i450gx },
@@ -183,5 +199,6 @@ struct pci_fixup pcibios_fixups[] = {
        { PCI_FIXUP_HEADER,     PCI_VENDOR_ID_VIA,      PCI_DEVICE_ID_VIA_8361,         pci_fixup_via_northbridge_bug },
        { PCI_FIXUP_HEADER,     PCI_VENDOR_ID_VIA,      PCI_DEVICE_ID_VIA_8367_0,       pci_fixup_via_northbridge_bug },
        { PCI_FIXUP_HEADER,     PCI_VENDOR_ID_NCR,      PCI_DEVICE_ID_NCR_53C810,       pci_fixup_ncr53c810 },
+       { PCI_FIXUP_HEADER,     PCI_VENDOR_ID_INTEL,    PCI_ANY_ID,                     pci_fixup_transparent_bridge },
        { 0 }
 };

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 060b94008a15bc3c3380a1860c21db7f2e6a1b13..6460e5f08eda0d4cf3b82ff9ca2a16ca714b40c6 100644 (file)
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -128,6 +128,13 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
        if (!dev)               /* It's a host bus, nothing to read */
                return;
 
+       if (dev->transparent) {
+               printk("Transparent bridge - %s\n", dev->name);
+               for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++)
+                       child->resource[i] = child->parent->resource[i];
+               return;
+       }
+
        for(i=0; i<3; i++)
                child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
 
@@ -149,13 +156,6 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
                res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
                res->start = base;
                res->end = limit + 0xfff;
-       } else {
-               /*
-                * Ugh. We don't know enough about this bridge. Just assume
-                * that it's entirely transparent.
-                */
-               printk(KERN_ERR "Unknown bridge resource %d: assuming transparent\n", 0);
-               child->resource[0] = child->parent->resource[0];
        }
 
        res = child->resource[1];
@@ -167,10 +167,6 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
                res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
                res->start = base;
                res->end = limit + 0xfffff;
-       } else {
-               /* See comment above. Same thing */
-               printk(KERN_ERR "Unknown bridge resource %d: assuming transparent\n", 1);
-               child->resource[1] = child->parent->resource[1];
        }
 
        res = child->resource[2];
@@ -197,10 +193,6 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
                res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM | IORESOURCE_PREFETCH;
                res->start = base;
                res->end = limit + 0xfffff;
-       } else {
-               /* See comments above */
-               printk(KERN_ERR "Unknown bridge resource %d: assuming transparent\n", 2);
-               child->resource[2] = child->parent->resource[2];
        }
 }
 
@@ -389,6 +381,10 @@ int pci_setup_device(struct pci_dev * dev)
        case PCI_HEADER_TYPE_BRIDGE:                /* bridge header */
                if (class != PCI_CLASS_BRIDGE_PCI)
                        goto bad;
+               /* The PCI-to-PCI bridge spec requires that subtractive
+                  decoding (i.e. transparent) bridge must have programming
+                  interface code of 0x01. */ 
+               dev->transparent = ((class & 0xff) == 1);
                pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
                break;
 

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index e66a3237f252083c53343563bcc650de605ee2cd..43aea3183d77bd5ae9019b8798fbf98e295d4d17 100644 (file)
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -471,6 +471,11 @@ static void __init quirk_dunord ( struct pci_dev * dev )
        r -> end = 0xffffff;
 }
 
+static void __init quirk_transparent_bridge(struct pci_dev *dev)
+{
+       dev->transparent = 1;
+}
+
 /*
  *  The main table of quirks.
  */
@@ -525,6 +530,13 @@ static struct pci_fixup pci_fixups[] __initdata = {
 
        { PCI_FIXUP_FINAL,      PCI_VENDOR_ID_AMD,      PCI_DEVICE_ID_AMD_VIPER_7410,   quirk_amd_ioapic },
        { PCI_FIXUP_FINAL,      PCI_VENDOR_ID_AMD,      PCI_DEVICE_ID_AMD_FE_GATE_700C, quirk_amd_ordering },
+       /*
+        * i82380FB mobile docking controller: its PCI-to-PCI bridge
+        * is subtractive decoding (transparent), and does indicate this
+        * in the ProgIf. Unfortunately, the ProgIf value is wrong - 0x80
+        * instead of 0x01.
+        */
+       { PCI_FIXUP_HEADER,     PCI_VENDOR_ID_INTEL,    PCI_DEVICE_ID_INTEL_82380FB,    quirk_transparent_bridge },
 
        { 0 }
 };

diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index 33efcd5717e9ddc4a264895a66170b0d4a370224..da3eb2e5f5cc3205942febb8b9bad51433eef4e8 100644 (file)
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -73,7 +73,7 @@ static int pci_assign_bus_resource(const struct pci_bus *bus,
        int i;
 
        type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
-       for (i = 0 ; i < 4; i++) {
+       for (i = 0 ; i < PCI_BUS_NUM_RESOURCES; i++) {
                struct resource *r = bus->resource[i];
                if (!r)
                        continue;

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 3c76341f02bf0d2a39bbb43ec0cccc25c835be23..b82ec8e411745a1fc212696e87f314d93a7300a9 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -386,6 +386,9 @@ struct pci_dev {
        int             ro;             /* ISAPnP: read only */
        unsigned short  regs;           /* ISAPnP: supported registers */
 
+       /* These fields are used by common fixups */
+       unsigned short  transparent:1;  /* Transparent PCI bridge */
+
        int (*prepare)(struct pci_dev *dev);    /* ISAPnP hooks */
        int (*activate)(struct pci_dev *dev);
        int (*deactivate)(struct pci_dev *dev);
@@ -406,6 +409,10 @@ struct pci_dev {
 #define PCI_ROM_RESOURCE 6
 #define PCI_BRIDGE_RESOURCES 7
 #define PCI_NUM_RESOURCES 11
+
+#ifndef PCI_BUS_NUM_RESOURCES
+#define PCI_BUS_NUM_RESOURCES 4
+#endif
   
 #define PCI_REGION_FLAG_MASK 0x0fU     /* These bits of resource flags tell us the PCI region flags */
 
@@ -415,7 +422,8 @@ struct pci_bus {
        struct list_head children;      /* list of child buses */
        struct list_head devices;       /* list of devices on this bus */
        struct pci_dev  *self;          /* bridge device as seen by parent */
-       struct resource *resource[4];   /* address space routed to this bus */
+       struct resource *resource[PCI_BUS_NUM_RESOURCES];
+                                       /* address space routed to this bus */
 
        struct pci_ops  *ops;           /* configuration access functions */
        void            *sysdata;       /* hook for sys-specific extension */