From f32ab7547161b9fa7ebfbc4f18ea1eb3fd49fe25 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Thu, 11 Jan 2018 14:23:29 +0100 Subject: x86/PCI: Add "pci=big_root_window" option for AMD 64-bit windows MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Only try to enable a 64-bit window on AMD CPUs when "pci=big_root_window" is specified. This taints the kernel because the new 64-bit window uses address space we don't know anything about, and it may contain unreported devices or memory that would conflict with the window. The pci_amd_enable_64bit_bar() quirk that enables the window is specific to AMD CPUs. The generic solution would be to have the firmware enable the window and describe it in the host bridge's _CRS method, or at least describe it in the _PRS method so the OS would have the option of enabling it. Signed-off-by: Christian König [bhelgaas: changelog, extend doc, mention taint in dmesg] Signed-off-by: Bjorn Helgaas --- arch/x86/include/asm/pci_x86.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/include') diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h index 7a5d6695abd3..eb66fa9cd0fc 100644 --- a/arch/x86/include/asm/pci_x86.h +++ b/arch/x86/include/asm/pci_x86.h @@ -38,6 +38,7 @@ do { \ #define PCI_NOASSIGN_ROMS 0x80000 #define PCI_ROOT_NO_CRS 0x100000 #define PCI_NOASSIGN_BARS 0x200000 +#define PCI_BIG_ROOT_WINDOW 0x400000 extern unsigned int pci_probe; extern unsigned long pirq_table_addr; -- cgit