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| author | Dmitry Osipenko <digetx@gmail.com> | 2019-03-07 01:55:19 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-09 09:17:22 +0200 |
| commit | 1715a46322fa17037f2b1cc05f3cf9e1046c8a9e (patch) | |
| tree | 8684e961edffbc5534d261eb43a2c13e8524d401 /drivers/gpu/drm | |
| parent | 132137d1bfa16d6b127d7b3761c07540ea42a529 (diff) | |
| download | linux-rpi3-1715a46322fa17037f2b1cc05f3cf9e1046c8a9e.tar.gz linux-rpi3-1715a46322fa17037f2b1cc05f3cf9e1046c8a9e.tar.bz2 linux-rpi3-1715a46322fa17037f2b1cc05f3cf9e1046c8a9e.zip | |
drm/tegra: gem: Fix CPU-cache maintenance for BO's allocated using get_pages()
commit 61b51fb51c01a519a249d28ec55c6513a13be5a3 upstream.
The allocated pages need to be invalidated in CPU caches. On ARM32 the
DMA_BIDIRECTIONAL flag only ensures that data is written-back to DRAM and
the data stays in CPU cache lines. While the DMA_FROM_DEVICE flag ensures
that the corresponding CPU cache lines are getting invalidated and nothing
more, that's exactly what is needed for a newly allocated pages.
This fixes randomly failing rendercheck tests on Tegra30 using the
Opentegra driver for tests that use small-sized pixmaps (10x10 and less,
i.e. 1-2 memory pages) because apparently CPU reads out stale data from
caches and/or that data is getting evicted to DRAM at the time of HW job
execution.
Fixes: bd43c9f0fa1f ("drm/tegra: gem: Map pages via the DMA API")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/gpu/drm')
| -rw-r--r-- | drivers/gpu/drm/tegra/gem.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c index 4f80100ff5f3..4cce11fd8836 100644 --- a/drivers/gpu/drm/tegra/gem.c +++ b/drivers/gpu/drm/tegra/gem.c @@ -204,7 +204,7 @@ static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo) { if (bo->pages) { dma_unmap_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents, - DMA_BIDIRECTIONAL); + DMA_FROM_DEVICE); drm_gem_put_pages(&bo->gem, bo->pages, true, true); sg_free_table(bo->sgt); kfree(bo->sgt); @@ -230,7 +230,7 @@ static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo) } err = dma_map_sg(drm->dev, bo->sgt->sgl, bo->sgt->nents, - DMA_BIDIRECTIONAL); + DMA_FROM_DEVICE); if (err == 0) { err = -EFAULT; goto free_sgt; |