From 7752d5cfe3d11ca0bb9c673ec38bd78ba6578f8e Mon Sep 17 00:00:00 2001 From: Robert Hancock Date: Fri, 15 Feb 2008 01:27:20 -0800 Subject: x86: validate against acpi motherboard resources This path adds validation of the MMCONFIG table against the ACPI reserved motherboard resources. If the MMCONFIG table is found to be reserved in ACPI, we don't bother checking the E820 table. The PCI Express firmware spec apparently tells BIOS developers that reservation in ACPI is required and E820 reservation is optional, so checking against ACPI first makes sense. Many BIOSes don't reserve the MMCONFIG region in E820 even though it is perfectly functional, the existing check needlessly disables MMCONFIG in these cases. In order to do this, MMCONFIG setup has been split into two phases. If PCI configuration type 1 is not available then MMCONFIG is enabled early as before. Otherwise, it is enabled later after the ACPI interpreter is enabled, since we need to be able to execute control methods in order to check the ACPI reserved resources. Presently this is just triggered off the end of ACPI interpreter initialization. There are a few other behavioral changes here: - Validate all MMCONFIG configurations provided, not just the first one. - Validate the entire required length of each configuration according to the provided ending bus number is reserved, not just the minimum required allocation. - Validate that the area is reserved even if we read it from the chipset directly and not from the MCFG table. This catches the case where the BIOS didn't set the location properly in the chipset and has mapped it over other things it shouldn't have. This also cleans up the MMCONFIG initialization functions so that they simply do nothing if MMCONFIG is not compiled in. Based on an original patch by Rajesh Shah from Intel. [akpm@linux-foundation.org: many fixes and cleanups] Signed-off-by: Robert Hancock Signed-off-by: Andi Kleen Cc: Andrew Morton Cc: Greg KH Signed-off-by: Thomas Gleixner Tested-by: Andi Kleen Cc: Rajesh Shah Cc: Jesse Barnes Acked-by: Linus Torvalds Cc: Andi Kleen Cc: Greg KH Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Thomas Gleixner --- arch/x86/pci/init.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'arch/x86/pci/init.c') diff --git a/arch/x86/pci/init.c b/arch/x86/pci/init.c index 3de9f9ba2da..2080b04b3bc 100644 --- a/arch/x86/pci/init.c +++ b/arch/x86/pci/init.c @@ -11,9 +11,7 @@ static __init int pci_access_init(void) #ifdef CONFIG_PCI_DIRECT type = pci_direct_probe(); #endif -#ifdef CONFIG_PCI_MMCONFIG - pci_mmcfg_init(type); -#endif + pci_mmcfg_early_init(type); if (raw_pci_ops) return 0; #ifdef CONFIG_PCI_BIOS -- cgit v1.2.3-70-g09d2