The TTM DMA only gets turned on when the SWIOTLB is enabled - but we might also want to turn it off when SWIOTLB is on to use the non-DMA TTM pool code.
In the future this parameter can be removed.
Signed-off-by: Konrad Rzeszutek Wilk konrad.wilk@oracle.com --- drivers/gpu/drm/ttm/ttm_page_alloc_dma.c | 4 ++++ include/drm/ttm/ttm_page_alloc.h | 4 ++-- 2 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c index 5a5739c..5909d28 100644 --- a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c +++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c @@ -51,6 +51,10 @@ #include <asm/agp.h> #endif
+int __read_mostly dma_ttm_disable; +MODULE_PARM_DESC(no_dma, "Disable TTM DMA pool"); +module_param_named(no_dma, dma_ttm_disable, bool, S_IRUGO); + #define NUM_PAGES_TO_ALLOC (PAGE_SIZE/sizeof(struct page *)) #define SMALL_ALLOCATION 16 #define FREE_ALL_PAGES (~0U) diff --git a/include/drm/ttm/ttm_page_alloc.h b/include/drm/ttm/ttm_page_alloc.h index a58331d..1dde3bd 100644 --- a/include/drm/ttm/ttm_page_alloc.h +++ b/include/drm/ttm/ttm_page_alloc.h @@ -103,10 +103,10 @@ extern struct ttm_page_alloc_func ttm_page_alloc_default; #ifdef CONFIG_SWIOTLB /* Defined in ttm_page_alloc_dma.c */ extern struct ttm_page_alloc_func ttm_page_alloc_dma; - +extern int dma_ttm_disable; static inline bool ttm_page_alloc_need_dma(void) { - if (swiotlb_nr_tbl()) { + if (!dma_ttm_disable && swiotlb_nr_tbl()) { ttm_page_alloc = &ttm_page_alloc_dma; return true; }