diff options
Diffstat (limited to 'arch/x86/kernel/pci-swiotlb.c')
| -rw-r--r-- | arch/x86/kernel/pci-swiotlb.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c index aaa6b7839f1..7d2829dde20 100644 --- a/arch/x86/kernel/pci-swiotlb.c +++ b/arch/x86/kernel/pci-swiotlb.c @@ -42,18 +42,31 @@ static struct dma_map_ops swiotlb_dma_ops = { .dma_supported = NULL, }; -void __init pci_swiotlb_init(void) +/* + * pci_swiotlb_detect - set swiotlb to 1 if necessary + * + * This returns non-zero if we are forced to use swiotlb (by the boot + * option). + */ +int __init pci_swiotlb_detect(void) { + int use_swiotlb = swiotlb | swiotlb_force; + /* don't initialize swiotlb if iommu=off (no_iommu=1) */ #ifdef CONFIG_X86_64 - if ((!iommu_detected && !no_iommu && max_pfn > MAX_DMA32_PFN)) + if (!no_iommu && max_pfn > MAX_DMA32_PFN) swiotlb = 1; #endif if (swiotlb_force) swiotlb = 1; + + return use_swiotlb; +} + +void __init pci_swiotlb_init(void) +{ if (swiotlb) { - printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n"); - swiotlb_init(); + swiotlb_init(0); dma_ops = &swiotlb_dma_ops; } } |