[PATCH 3/5] x86: mmconf enable mcfg early

From: Yinghai Lu
Date: Fri Feb 15 2008 - 04:26:35 EST


From: Yinghai Lu <Yinghai.Lu@xxxxxxx>

Patch
x86: validate against ACPI motherboard resources

changed the mmconf init sequence, and init MMCONF late in acpi_init.

here change it back to old sequence
1. check hostbridge in early
2. check MCFG with e820 in early
3. if all fail, will check MCFg with acpi _CRS in acpi_init

So we can make MCONF working again when acpi=off is set if hostbridge support
that.

Signed-off-by: Yinghai Lu <yinghai.lu@xxxxxxx>
Cc: Greg KH <greg@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

arch/x86/pci/mmconfig-shared.c | 106 +++++++++++++++++--------------
1 file changed, 61 insertions(+), 45 deletions(-)

Index: linux-2.6/arch/x86/pci/mmconfig-shared.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/mmconfig-shared.c
+++ linux-2.6/arch/x86/pci/mmconfig-shared.c
@@ -241,7 +241,7 @@ static int __init is_acpi_reserved(unsig
return mcfg_res.flags;
}

-static void __init pci_mmcfg_reject_broken(void)
+static void __init pci_mmcfg_reject_broken(int type, int early)
{
typeof(pci_mmcfg_config[0]) *cfg;
int i;
@@ -266,34 +266,43 @@ static void __init pci_mmcfg_reject_brok
}

for (i = 0; i < pci_mmcfg_config_num; i++) {
+ int valid = 0;
u32 size = (cfg->end_bus_number + 1) << 20;
cfg = &pci_mmcfg_config[i];
- printk(KERN_NOTICE "PCI: MCFG configuration %d: base %lu "
+ printk(KERN_NOTICE "PCI: MCFG configuration %d: base %lx "
"segment %hu buses %u - %u\n",
i, (unsigned long)cfg->address, cfg->pci_segment,
(unsigned int)cfg->start_bus_number,
(unsigned int)cfg->end_bus_number);
- if (is_acpi_reserved(cfg->address, cfg->address + size - 1)) {
+
+ if (!early &&
+ is_acpi_reserved(cfg->address, cfg->address + size - 1)) {
printk(KERN_NOTICE "PCI: MCFG area at %Lx reserved "
"in ACPI motherboard resources\n",
cfg->address);
- } else {
+ valid = 1;
+ }
+
+ if (valid)
+ continue;
+
+ if (!early)
printk(KERN_ERR "PCI: BIOS Bug: MCFG area at %Lx is not"
" reserved in ACPI motherboard resources\n",
cfg->address);
- /* Don't try to do this check unless configuration
- type 1 is available. */
- if ((pci_probe & PCI_PROBE_CONF1) &&
- e820_all_mapped(cfg->address,
- cfg->address + size - 1,
- E820_RESERVED))
- printk(KERN_NOTICE
- "PCI: MCFG area at %Lx reserved in "
- "E820\n",
- cfg->address);
- else
- goto reject;
+ /* Don't try to do this check unless configuration
+ type 1 is available. */
+ if (type == 1 && e820_all_mapped(cfg->address,
+ cfg->address + size - 1,
+ E820_RESERVED)) {
+ printk(KERN_NOTICE
+ "PCI: MCFG area at %Lx reserved in E820\n",
+ cfg->address);
+ valid = 1;
}
+
+ if (!valid)
+ goto reject;
}

return;
@@ -306,46 +315,36 @@ reject:
pci_mmcfg_config_num = 0;
}

-void __init pci_mmcfg_early_init(int type)
-{
- if ((pci_probe & PCI_PROBE_MMCONF) == 0)
- return;
-
- /* If type 1 access is available, no need to enable MMCONFIG yet, we can
- defer until later when the ACPI interpreter is available to better
- validate things. */
- if (type == 1)
- 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;
+static int __initdata known_bridge;

- if (pci_mmcfg_arch_init())
- pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
-}
-
-void __init pci_mmcfg_late_init(void)
+void __init __pci_mmcfg_init(int type, int early)
{
- int known_bridge = 0;
-
/* MMCONFIG disabled */
if ((pci_probe & PCI_PROBE_MMCONF) == 0)
return;

/* MMCONFIG already enabled */
- if (!(pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF))
+ if (!early && !(pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF))
return;

- if ((pci_probe & PCI_PROBE_CONF1) && pci_mmcfg_check_hostbridge())
- known_bridge = 1;
- else
- acpi_table_parse(ACPI_SIG_MCFG, acpi_parse_mcfg);
+ /* for late to exit */
+ if (known_bridge)
+ return;

- pci_mmcfg_reject_broken();
+ if (early && type == 1) {
+ if (pci_mmcfg_check_hostbridge())
+ known_bridge = 1;
+#if 0
+ /* check e820 in late? */
+ else
+ return;
+#endif
+ }
+
+ if (!known_bridge) {
+ acpi_table_parse(ACPI_SIG_MCFG, acpi_parse_mcfg);
+ pci_mmcfg_reject_broken(type, early);
+ }

if ((pci_mmcfg_config_num == 0) ||
(pci_mmcfg_config == NULL) ||
@@ -365,6 +364,21 @@ void __init pci_mmcfg_late_init(void)
}
}

+void __init pci_mmcfg_early_init(int type)
+{
+ __pci_mmcfg_init(type, 1);
+}
+
+void __init pci_mmcfg_late_init(void)
+{
+ int type = 0;
+
+ if (pci_probe & PCI_PROBE_CONF1)
+ type = 1;
+
+ __pci_mmcfg_init(type, 0);
+}
+
static int __init pci_mmcfg_late_insert_resources(void)
{
/*
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/