[PATCH] mmconfig: Share parts of mmconfig code between i386 and x86-64

i386 and x86-64 pci mmconfig code have a lot in common.  So share what's
shareable between the two.

Signed-off-by: Olivier Galibert <galibert@pobox.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>

4 files changed, 97 insertions, 71 deletions

diff --git a/arch/i386/pci/Makefile b/arch/i386/pci/Makefile
index 1594d2f55c8f..44650e03308b 100644
--- a/arch/i386/pci/Makefile
+++ b/arch/i386/pci/Makefile
@@ -1,7 +1,7 @@
 obj-y                           := i386.o init.o
 
 obj-$(CONFIG_PCI_BIOS)          += pcbios.o
-obj-$(CONFIG_PCI_MMCONFIG)      += mmconfig.o direct.o
+obj-$(CONFIG_PCI_MMCONFIG)      += mmconfig.o direct.o mmconfig-shared.o
 obj-$(CONFIG_PCI_DIRECT)        += direct.o
 
 pci-y                           := fixup.o
diff --git a/arch/i386/pci/mmconfig-shared.c b/arch/i386/pci/mmconfig-shared.c
new file mode 100644
index 000000000000..998e04f6d68f
--- /dev/null
+++ b/arch/i386/pci/mmconfig-shared.c
@@ -0,0 +1,86 @@
+/*
+ * mmconfig-shared.c - Low-level direct PCI config space access via
+ *                     MMCONFIG - common code between i386 and x86-64.
+ *
+ * This code does:
+ * - ACPI decoding and validation
+ *
+ * Per-architecture code takes care of the mappings and accesses
+ * themselves.
+ */
+
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/bitmap.h>
+#include <asm/e820.h>
+
+#include "pci.h"
+
+/* aperture is up to 256MB but BIOS may reserve less */
+#define MMCONFIG_APER_MIN       (2 * 1024*1024)
+#define MMCONFIG_APER_MAX       (256 * 1024*1024)
+
+/* Verify the first 16 busses. We assume that systems with more busses
+   get MCFG right. */
+#define PCI_MMCFG_MAX_CHECK_BUS 16
+
+DECLARE_BITMAP(pci_mmcfg_fallback_slots, 32*PCI_MMCFG_MAX_CHECK_BUS);
+
+/* K8 systems have some devices (typically in the builtin northbridge)
+   that are only accessible using type1
+   Normally this can be expressed in the MCFG by not listing them
+   and assigning suitable _SEGs, but this isn't implemented in some BIOS.
+   Instead try to discover all devices on bus 0 that are unreachable using MM
+   and fallback for them. */
+static __init void unreachable_devices(void)
+{
+        int i, k;
+        /* Use the max bus number from ACPI here? */
+        for (k = 0; k < PCI_MMCFG_MAX_CHECK_BUS; k++) {
+                for (i = 0; i < 32; i++) {
+                        u32 val1, val2;
+
+                        pci_conf1_read(0, k, PCI_DEVFN(i,0), 0, 4, &val1);
+                        if (val1 == 0xffffffff)
+                                continue;
+
+                        raw_pci_ops->read(0, k, PCI_DEVFN(i, 0), 0, 4, &val2);
+                        if (val1 != val2) {
+                                set_bit(i + 32*k, pci_mmcfg_fallback_slots);
+                                printk(KERN_NOTICE "PCI: No mmconfig possible"
+                                       " on device %02x:%02x\n", k, i);
+                        }
+                }
+        }
+}
+
+void __init pci_mmcfg_init(int type)
+{
+        if ((pci_probe & PCI_PROBE_MMCONF) == 0)
+                return;
+
+        acpi_table_parse(ACPI_SIG_MCFG, acpi_parse_mcfg);
+
+        if ((pci_mmcfg_config_num == 0) ||
+            (pci_mmcfg_config == NULL) ||
+            (pci_mmcfg_config[0].address == 0))
+                return;
+
+        /* Only do this check when type 1 works. If it doesn't work
+           assume we run on a Mac and always use MCFG */
+        if (type == 1 &&
+            !e820_all_mapped(pci_mmcfg_config[0].address,
+                             pci_mmcfg_config[0].address + MMCONFIG_APER_MIN,
+                             E820_RESERVED)) {
+                printk(KERN_ERR "PCI: BIOS Bug: MCFG area at %Lx is not E820-reserved\n",
+                                pci_mmcfg_config[0].address);
+                printk(KERN_ERR "PCI: Not using MMCONFIG.\n");
+                return;
+        }
+
+        if (pci_mmcfg_arch_init()) {
+                unreachable_devices();
+                pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
+        }
+}
diff --git a/arch/i386/pci/mmconfig.c b/arch/i386/pci/mmconfig.c
index 5700220dcf5f..97dcaaa0de0f 100644
--- a/arch/i386/pci/mmconfig.c
+++ b/arch/i386/pci/mmconfig.c
@@ -15,21 +15,13 @@
 #include <asm/e820.h>
 #include "pci.h"
 
-/* aperture is up to 256MB but BIOS may reserve less */
-#define MMCONFIG_APER_MIN       (2 * 1024*1024)
-#define MMCONFIG_APER_MAX       (256 * 1024*1024)
-
 /* Assume systems with more busses have correct MCFG */
-#define MAX_CHECK_BUS 16
-
 #define mmcfg_virt_addr ((void __iomem *) fix_to_virt(FIX_PCIE_MCFG))
 
 /* The base address of the last MMCONFIG device accessed */
 static u32 mmcfg_last_accessed_device;
 static int mmcfg_last_accessed_cpu;
 
-static DECLARE_BITMAP(fallback_slots, MAX_CHECK_BUS*32);
-
 /*
  * Functions for accessing PCI configuration space with MMCONFIG accesses
  */
@@ -38,8 +30,8 @@ static u32 get_base_addr(unsigned int seg, int bus, unsigned devfn)
         int cfg_num = -1;
         struct acpi_mcfg_allocation *cfg;
 
-        if (seg == 0 && bus < MAX_CHECK_BUS &&
-            test_bit(PCI_SLOT(devfn) + 32*bus, fallback_slots))
+        if (seg == 0 && bus < PCI_MMCFG_MAX_CHECK_BUS &&
+            test_bit(PCI_SLOT(devfn) + 32*bus, pci_mmcfg_fallback_slots))
                 return 0;
 
         while (1) {
@@ -158,67 +150,9 @@ static struct pci_raw_ops pci_mmcfg = {
         .write =        pci_mmcfg_write,
 };
 
-/* K8 systems have some devices (typically in the builtin northbridge)
-   that are only accessible using type1
-   Normally this can be expressed in the MCFG by not listing them
-   and assigning suitable _SEGs, but this isn't implemented in some BIOS.
-   Instead try to discover all devices on bus 0 that are unreachable using MM
-   and fallback for them. */
-static __init void unreachable_devices(void)
+int __init pci_mmcfg_arch_init(void)
 {
-        int i, k;
-        unsigned long flags;
-
-        for (k = 0; k < MAX_CHECK_BUS; k++) {
-                for (i = 0; i < 32; i++) {
-                        u32 val1;
-                        u32 addr;
-
-                        pci_conf1_read(0, k, PCI_DEVFN(i, 0), 0, 4, &val1);
-                        if (val1 == 0xffffffff)
-                                continue;
-
-                        /* Locking probably not needed, but safer */
-                        spin_lock_irqsave(&pci_config_lock, flags);
-                        addr = get_base_addr(0, k, PCI_DEVFN(i, 0));
-                        if (addr != 0)
-                                pci_exp_set_dev_base(addr, k, PCI_DEVFN(i, 0));
-                        if (addr == 0 ||
-                            readl((u32 __iomem *)mmcfg_virt_addr) != val1) {
-                                set_bit(i + 32*k, fallback_slots);
-                                printk(KERN_NOTICE
-                        "PCI: No mmconfig possible on %x:%x\n", k, i);
-                        }
-                        spin_unlock_irqrestore(&pci_config_lock, flags);
-                }
-        }
-}
-
-void __init pci_mmcfg_init(int type)
-{
-        if ((pci_probe & PCI_PROBE_MMCONF) == 0)
-                return;
-
-        acpi_table_parse(ACPI_SIG_MCFG, acpi_parse_mcfg);
-        if ((pci_mmcfg_config_num == 0) ||
-            (pci_mmcfg_config == NULL) ||
-            (pci_mmcfg_config[0].address == 0))
-                return;
-
-        /* Only do this check when type 1 works. If it doesn't work
-           assume we run on a Mac and always use MCFG */
-        if (type == 1 && !e820_all_mapped(pci_mmcfg_config[0].address,
-                        pci_mmcfg_config[0].address + MMCONFIG_APER_MIN,
-                        E820_RESERVED)) {
-                printk(KERN_ERR "PCI: BIOS Bug: MCFG area at %lx is not E820-reserved\n",
-                                (unsigned long)pci_mmcfg_config[0].address);
-                printk(KERN_ERR "PCI: Not using MMCONFIG.\n");
-                return;
-        }
-
         printk(KERN_INFO "PCI: Using MMCONFIG\n");
         raw_pci_ops = &pci_mmcfg;
-        pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
-
-        unreachable_devices();
+        return 1;
 }
diff --git a/arch/i386/pci/pci.h b/arch/i386/pci/pci.h
index a0a25180b61a..0270c80d99cc 100644
--- a/arch/i386/pci/pci.h
+++ b/arch/i386/pci/pci.h
@@ -94,3 +94,9 @@ extern void pci_pcbios_init(void);
 extern void pci_mmcfg_init(int type);
 extern void pcibios_sort(void);
 
+/* pci-mmconfig.c */
+
+#define PCI_MMCFG_MAX_CHECK_BUS 16
+extern DECLARE_BITMAP(pci_mmcfg_fallback_slots, 32*PCI_MMCFG_MAX_CHECK_BUS);
+
+extern int pci_mmcfg_arch_init(void);