io mapped memory should not be directly dereferenced to ensure portability. io memory should be read/written/copied using helper functions. i915_memcpy_from_wc() function was used to copy the data from io memory to a temporary buffer and pointer to the temporary buffer was passed to CRC calculation function. But i915_memcpy_from_wc() only does a copy if the platform supports fast copy using non-temporal instructions. Otherwise the pointer to io memory was passed for CRC calculation. CRC function will directly dereference io memory and would not work properly on non-x86 platforms. To make it portable, it should be ensured always temporary buffer is used for CRC and not io memory. drm_memcpy_from_wc_vaddr() is now used for copying instead of i915_memcpy_from_wc() for 2 reasons. - i915_memcpy_from_wc() will be deprecated. - drm_memcpy_from_wc_vaddr() will not fail if the fast copy is not supported but uses memcpy_fromio as fallback for copying.
Cc: Matthew Brost matthew.brost@intel.com Cc: Michał Winiarski michal.winiarski@intel.com
Signed-off-by: Balasubramani Vivekanandan balasubramani.vivekanandan@intel.com Acked-by: Nirmoy Das nirmoy.das@intel.com --- drivers/gpu/drm/i915/gt/selftest_reset.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/selftest_reset.c b/drivers/gpu/drm/i915/gt/selftest_reset.c index 37c38bdd5f47..7a455583c687 100644 --- a/drivers/gpu/drm/i915/gt/selftest_reset.c +++ b/drivers/gpu/drm/i915/gt/selftest_reset.c @@ -3,6 +3,7 @@ * Copyright © 2018 Intel Corporation */
+#include <drm/drm_cache.h> #include <linux/crc32.h>
#include "gem/i915_gem_stolen.h" @@ -82,7 +83,7 @@ __igt_reset_stolen(struct intel_gt *gt, for (page = 0; page < num_pages; page++) { dma_addr_t dma = (dma_addr_t)dsm->start + (page << PAGE_SHIFT); void __iomem *s; - void *in; + struct iosys_map src_map;
ggtt->vm.insert_page(&ggtt->vm, dma, ggtt->error_capture.start, @@ -98,10 +99,9 @@ __igt_reset_stolen(struct intel_gt *gt, ((page + 1) << PAGE_SHIFT) - 1)) memset_io(s, STACK_MAGIC, PAGE_SIZE);
- in = (void __force *)s; - if (i915_memcpy_from_wc(tmp, in, PAGE_SIZE)) - in = tmp; - crc[page] = crc32_le(0, in, PAGE_SIZE); + iosys_map_set_vaddr_iomem(&src_map, s); + drm_memcpy_from_wc_vaddr(tmp, &src_map, 0, PAGE_SIZE); + crc[page] = crc32_le(0, tmp, PAGE_SIZE);
io_mapping_unmap(s); } @@ -122,7 +122,7 @@ __igt_reset_stolen(struct intel_gt *gt, for (page = 0; page < num_pages; page++) { dma_addr_t dma = (dma_addr_t)dsm->start + (page << PAGE_SHIFT); void __iomem *s; - void *in; + struct iosys_map src_map; u32 x;
ggtt->vm.insert_page(&ggtt->vm, dma, @@ -134,10 +134,9 @@ __igt_reset_stolen(struct intel_gt *gt, ggtt->error_capture.start, PAGE_SIZE);
- in = (void __force *)s; - if (i915_memcpy_from_wc(tmp, in, PAGE_SIZE)) - in = tmp; - x = crc32_le(0, in, PAGE_SIZE); + iosys_map_set_vaddr_iomem(&src_map, s); + drm_memcpy_from_wc_vaddr(tmp, &src_map, 0, PAGE_SIZE); + x = crc32_le(0, tmp, PAGE_SIZE);
if (x != crc[page] && !__drm_mm_interval_first(>->i915->mm.stolen, @@ -146,7 +145,7 @@ __igt_reset_stolen(struct intel_gt *gt, pr_debug("unused stolen page %pa modified by GPU reset\n", &page); if (count++ == 0) - igt_hexdump(in, PAGE_SIZE); + igt_hexdump(tmp, PAGE_SIZE); max = page; }