[PATCH] x86_64: Fix swiotlb=force

It was broken before. But having it is important as possible hardware
bug workaround.

And previously there was no way to force swiotlb if there is another IOMMU.
Side effect is that iommu=force won't force swiotlb anymore even if there
isn't another IOMMU.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Andi Kleen 2006-07-29 21:42:49 +02:00 committed by Linus Torvalds
parent 355540f333
commit 65f87d8a8a
2 changed files with 5 additions and 2 deletions

View file

@ -31,9 +31,10 @@ struct dma_mapping_ops swiotlb_dma_ops = {
void pci_swiotlb_init(void)
{
/* don't initialize swiotlb if iommu=off (no_iommu=1) */
if (!iommu_detected && !no_iommu &&
(end_pfn > MAX_DMA32_PFN || force_iommu))
if (!iommu_detected && !no_iommu && end_pfn > MAX_DMA32_PFN)
swiotlb = 1;
if (swiotlb_force)
swiotlb = 1;
if (swiotlb) {
printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n");
swiotlb_init();

View file

@ -42,6 +42,8 @@ extern void swiotlb_free_coherent (struct device *hwdev, size_t size,
extern int swiotlb_dma_supported(struct device *hwdev, u64 mask);
extern void swiotlb_init(void);
extern int swiotlb_force;
#ifdef CONFIG_SWIOTLB
extern int swiotlb;
#else