Revert mmiocfg heuristics and blacklist changes

This reverts commits 11012d419cfc0e0f78ca356aca03674217910124 and
40dd2d20f220eda1cd0da8ea3f0f9db8971ba237, which allowed us to use the
MMIO accesses for PCI config cycles even without the area being marked
reserved in the e820 memory tables.

Those changes were needed for EFI-environment Intel macs, but broke some
newer Intel 965 boards, so for now it's better to revert to our old
2.6.17 behaviour and at least avoid introducing any new breakage.

Andi Kleen has a set of patches that work with both EFI and the broken
Intel 965 boards, which will be applied once they get wider testing.

Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Edgar Hucek <hostmaster@ed-soft.at>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 87a17337c7f638a262a5e530e08c7a1a4eff249c..71d05f481727669ce88a517a3cd631988fd9c32b 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1189,8 +1189,6 @@ running once the system is up.
                                Mechanism 2.
                nommconf        [IA-32,X86_64] Disable use of MMCONFIG for PCI
                                Configuration
-               mmconf          [IA-32,X86_64] Force MMCONFIG. This is useful
-                               to override the builtin blacklist.
                nomsi           [MSI] If the PCI_MSI kernel config parameter is
                                enabled, this kernel boot option can be used to
                                disable the use of MSI interrupts system-wide.

diff --git a/arch/i386/kernel/setup.c b/arch/i386/kernel/setup.c
index 345ffb7d904d382332bf518292926288caa1c0da..f1682206d304d31fb650992bf8a1cb551b2c54ee 100644 (file)
--- a/arch/i386/kernel/setup.c
+++ b/arch/i386/kernel/setup.c
@@ -956,6 +956,38 @@ efi_memory_present_wrapper(unsigned long start, unsigned long end, void *arg)
        return 0;
 }
 
+ /*
+  * This function checks if the entire range <start,end> is mapped with type.
+  *
+  * Note: this function only works correct if the e820 table is sorted and
+  * not-overlapping, which is the case
+  */
+int __init
+e820_all_mapped(unsigned long s, unsigned long e, unsigned type)
+{
+       u64 start = s;
+       u64 end = e;
+       int i;
+       for (i = 0; i < e820.nr_map; i++) {
+               struct e820entry *ei = &e820.map[i];
+               if (type && ei->type != type)
+                       continue;
+               /* is the region (part) in overlap with the current region ?*/
+               if (ei->addr >= end || ei->addr + ei->size <= start)
+                       continue;
+               /* if the region is at the beginning of <start,end> we move
+                * start to the end of the region since it's ok until there
+                */
+               if (ei->addr <= start)
+                       start = ei->addr + ei->size;
+               /* if start is now at or beyond end, we're done, full
+                * coverage */
+               if (start >= end)
+                       return 1; /* we're done */
+       }
+       return 0;
+}
+
 /*
  * Find the highest page frame number we have available
  */

diff --git a/arch/i386/pci/common.c b/arch/i386/pci/common.c
index 1220dd828ce3e929d4d069feda59bd16d94f50b3..0a362e3aeac55aba443e5901a71bbe7e465e841a 100644 (file)
--- a/arch/i386/pci/common.c
+++ b/arch/i386/pci/common.c
@@ -237,11 +237,6 @@ char * __devinit  pcibios_setup(char *str)
                pci_probe &= ~PCI_PROBE_MMCONF;
                return NULL;
        }
-       /* override DMI blacklist */
-       else if (!strcmp(str, "mmconf")) {
-               pci_probe |= PCI_PROBE_MMCONF_FORCE;
-               return NULL;
-       }
 #endif
        else if (!strcmp(str, "noacpi")) {
                acpi_noirq_set();

diff --git a/arch/i386/pci/mmconfig.c b/arch/i386/pci/mmconfig.c
index ef5a2faa7d824728d4c44cade01a2f2c023adca2..972180f738d9ae0d15fe059953fe2985cf454c09 100644 (file)
--- a/arch/i386/pci/mmconfig.c
+++ b/arch/i386/pci/mmconfig.c
@@ -12,7 +12,6 @@
 #include <linux/pci.h>
 #include <linux/init.h>
 #include <linux/acpi.h>
-#include <linux/dmi.h>
 #include <asm/e820.h>
 #include "pci.h"
 
@@ -188,31 +187,9 @@ static __init void unreachable_devices(void)
        }
 }
 
-static int disable_mcfg(struct dmi_system_id *d)
-{
-       printk("PCI: %s detected. Disabling MCFG.\n", d->ident);
-       pci_probe &= ~PCI_PROBE_MMCONF;
-       return 0;
-}
-
-static struct dmi_system_id __initdata dmi_bad_mcfg[] = {
-       /* Has broken MCFG table that makes the system hang when used */
-        {
-         .callback = disable_mcfg,
-         .ident = "Intel D3C5105 SDV",
-         .matches = {
-                     DMI_MATCH(DMI_BIOS_VENDOR, "Intel"),
-                     DMI_MATCH(DMI_BOARD_NAME, "D26928"),
-                     },
-         },
-         {}
-};
-
 void __init pci_mmcfg_init(void)
 {
-       dmi_check_system(dmi_bad_mcfg);
-
-       if ((pci_probe & (PCI_PROBE_MMCONF_FORCE|PCI_PROBE_MMCONF)) == 0)
+       if ((pci_probe & PCI_PROBE_MMCONF) == 0)
                return;
 
        acpi_table_parse(ACPI_MCFG, acpi_parse_mcfg);
@@ -221,6 +198,15 @@ void __init pci_mmcfg_init(void)
            (pci_mmcfg_config[0].base_address == 0))
                return;
 
+       if (!e820_all_mapped(pci_mmcfg_config[0].base_address,
+                       pci_mmcfg_config[0].base_address + MMCONFIG_APER_MIN,
+                       E820_RESERVED)) {
+               printk(KERN_ERR "PCI: BIOS Bug: MCFG area at %x is not E820-reserved\n",
+                               pci_mmcfg_config[0].base_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;

diff --git a/arch/i386/pci/pci.h b/arch/i386/pci/pci.h
index 49a849b3a2414712672ec97b57548df5fdf2b075..bf4e79335388b533b6149dcf403533b6ce687c7e 100644 (file)
--- a/arch/i386/pci/pci.h
+++ b/arch/i386/pci/pci.h
@@ -16,8 +16,7 @@
 #define PCI_PROBE_CONF1                0x0002
 #define PCI_PROBE_CONF2                0x0004
 #define PCI_PROBE_MMCONF       0x0008
-#define PCI_PROBE_MMCONF_FORCE 0x0010
-#define PCI_PROBE_MASK         0x00ff
+#define PCI_PROBE_MASK         0x000f
 
 #define PCI_NO_SORT            0x0100
 #define PCI_BIOS_SORT          0x0200

diff --git a/arch/x86_64/kernel/e820.c b/arch/x86_64/kernel/e820.c
index 764bf23c7103ff2de7ffcecff581910df8ae517e..d6d7f731f6f0edd78509fca24599caeec8fd9745 100644 (file)
--- a/arch/x86_64/kernel/e820.c
+++ b/arch/x86_64/kernel/e820.c
@@ -108,6 +108,35 @@ e820_any_mapped(unsigned long start, unsigned long end, unsigned type)
        return 0;
 }
 
+/*
+ * This function checks if the entire range <start,end> is mapped with type.
+ *
+ * Note: this function only works correct if the e820 table is sorted and
+ * not-overlapping, which is the case
+ */
+int __init e820_all_mapped(unsigned long start, unsigned long end, unsigned type)
+{
+       int i;
+       for (i = 0; i < e820.nr_map; i++) {
+               struct e820entry *ei = &e820.map[i];
+               if (type && ei->type != type)
+                       continue;
+               /* is the region (part) in overlap with the current region ?*/
+               if (ei->addr >= end || ei->addr + ei->size <= start)
+                       continue;
+
+               /* if the region is at the beginning of <start,end> we move
+                * start to the end of the region since it's ok until there
+                */
+               if (ei->addr <= start)
+                       start = ei->addr + ei->size;
+               /* if start is now at or beyond end, we're done, full coverage */
+               if (start >= end)
+                       return 1; /* we're done */
+       }
+       return 0;
+}
+
 /* 
  * Find a free area in a specific range. 
  */ 

diff --git a/arch/x86_64/pci/mmconfig.c b/arch/x86_64/pci/mmconfig.c
index 2d48a7941d489beff692a8abd50e1c444726e159..3c55c76c6fd5de3d262e20fd7727653cc6849750 100644 (file)
--- a/arch/x86_64/pci/mmconfig.c
+++ b/arch/x86_64/pci/mmconfig.c
@@ -9,7 +9,6 @@
 #include <linux/init.h>
 #include <linux/acpi.h>
 #include <linux/bitmap.h>
-#include <linux/dmi.h>
 #include <asm/e820.h>
 
 #include "pci.h"
@@ -165,33 +164,11 @@ static __init void unreachable_devices(void)
        }
 }
 
-static int disable_mcfg(struct dmi_system_id *d)
-{
-       printk("PCI: %s detected. Disabling MCFG.\n", d->ident);
-       pci_probe &= ~PCI_PROBE_MMCONF;
-       return 0;
-}
-
-static struct dmi_system_id __initdata dmi_bad_mcfg[] = {
-       /* Has broken MCFG table that makes the system hang when used */
-        {
-         .callback = disable_mcfg,
-         .ident = "Intel D3C5105 SDV",
-         .matches = {
-                     DMI_MATCH(DMI_BIOS_VENDOR, "Intel"),
-                     DMI_MATCH(DMI_BOARD_NAME, "D26928"),
-                     },
-         },
-         {}
-};
-
 void __init pci_mmcfg_init(void)
 {
        int i;
 
-       dmi_check_system(dmi_bad_mcfg);
-
-       if ((pci_probe & (PCI_PROBE_MMCONF|PCI_PROBE_MMCONF_FORCE)) == 0)
+       if ((pci_probe & PCI_PROBE_MMCONF) == 0)
                return;
 
        acpi_table_parse(ACPI_MCFG, acpi_parse_mcfg);
@@ -200,6 +177,15 @@ void __init pci_mmcfg_init(void)
            (pci_mmcfg_config[0].base_address == 0))
                return;
 
+       if (!e820_all_mapped(pci_mmcfg_config[0].base_address,
+                       pci_mmcfg_config[0].base_address + MMCONFIG_APER_MIN,
+                       E820_RESERVED)) {
+               printk(KERN_ERR "PCI: BIOS Bug: MCFG area at %x is not E820-reserved\n",
+                               pci_mmcfg_config[0].base_address);
+               printk(KERN_ERR "PCI: Not using MMCONFIG.\n");
+               return;
+       }
+
        /* RED-PEN i386 doesn't do _nocache right now */
        pci_mmcfg_virt = kmalloc(sizeof(*pci_mmcfg_virt) * pci_mmcfg_config_num, GFP_KERNEL);
        if (pci_mmcfg_virt == NULL) {