From de957628ce7c84764ff41331111036b3ae5bad0f Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Tue, 10 Nov 2009 19:46:14 +0900 Subject: x86: GART: Convert gart_iommu_hole_init() to use iommu_init hook This changes gart_iommu_hole_init() to set gart_iommu_init() to iommu_init hook if gart_iommu_hole_init() finds the GART IOMMU. We can kill the code to check if we found the IOMMU in gart_iommu_init() since gart_iommu_hole_init() sets gart_iommu_init() only when it found the IOMMU. Signed-off-by: FUJITA Tomonori Cc: chrisw@sous-sol.org Cc: dwmw2@infradead.org Cc: joerg.roedel@amd.com Cc: muli@il.ibm.com LKML-Reference: <1257849980-22640-4-git-send-email-fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Ingo Molnar --- arch/x86/kernel/aperture_64.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86/kernel/aperture_64.c') diff --git a/arch/x86/kernel/aperture_64.c b/arch/x86/kernel/aperture_64.c index 128111d8ffe0..03933cf0b63c 100644 --- a/arch/x86/kernel/aperture_64.c +++ b/arch/x86/kernel/aperture_64.c @@ -28,6 +28,7 @@ #include #include #include +#include int gart_iommu_aperture; int gart_iommu_aperture_disabled __initdata; @@ -400,6 +401,7 @@ void __init gart_iommu_hole_init(void) iommu_detected = 1; gart_iommu_aperture = 1; + x86_init.iommu.iommu_init = gart_iommu_init; aper_order = (read_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL) >> 1) & 7; aper_size = (32 * 1024 * 1024) << aper_order; -- cgit v1.2.3 From 75f1cdf1dda92cae037ec848ae63690d91913eac Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Tue, 10 Nov 2009 19:46:20 +0900 Subject: x86: Handle HW IOMMU initialization failure gracefully If HW IOMMU initialization fails (Intel VT-d often does this, typically due to BIOS bugs), we fall back to nommu. It doesn't work for the majority since nowadays we have more than 4GB memory so we must use swiotlb instead of nommu. The problem is that it's too late to initialize swiotlb when HW IOMMU initialization fails. We need to allocate swiotlb memory earlier from bootmem allocator. Chris explained the issue in detail: http://marc.info/?l=linux-kernel&m=125657444317079&w=2 The current x86 IOMMU initialization sequence is too complicated and handling the above issue makes it more hacky. This patch changes x86 IOMMU initialization sequence to handle the above issue cleanly. The new x86 IOMMU initialization sequence are: 1. we initialize the swiotlb (and setting swiotlb to 1) in the case of (max_pfn > MAX_DMA32_PFN && !no_iommu). dma_ops is set to swiotlb_dma_ops or nommu_dma_ops. if swiotlb usage is forced by the boot option, we finish here. 2. we call the detection functions of all the IOMMUs 3. the detection function sets x86_init.iommu.iommu_init to the IOMMU initialization function (so we can avoid calling the initialization functions of all the IOMMUs needlessly). 4. if the IOMMU initialization function doesn't need to swiotlb then sets swiotlb to zero (e.g. the initialization is sucessful). 5. if we find that swiotlb is set to zero, we free swiotlb resource. Signed-off-by: FUJITA Tomonori Cc: chrisw@sous-sol.org Cc: dwmw2@infradead.org Cc: joerg.roedel@amd.com Cc: muli@il.ibm.com LKML-Reference: <1257849980-22640-10-git-send-email-fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Ingo Molnar --- arch/x86/kernel/aperture_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel/aperture_64.c') diff --git a/arch/x86/kernel/aperture_64.c b/arch/x86/kernel/aperture_64.c index 03933cf0b63c..e0dfb6856aa2 100644 --- a/arch/x86/kernel/aperture_64.c +++ b/arch/x86/kernel/aperture_64.c @@ -458,7 +458,7 @@ out: if (aper_alloc) { /* Got the aperture from the AGP bridge */ - } else if (swiotlb && !valid_agp) { + } else if (!valid_agp) { /* Do nothing */ } else if ((!no_iommu && max_pfn > MAX_DMA32_PFN) || force_iommu || -- cgit v1.2.3