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273da5a046
This partially reverts the DMA API support that was recently merged because it was causing performance regressions on older Tegra devices. Unfortunately, the cache maintenance performed by dma_map_sg() and dma_unmap_sg() causes performance to drop by a factor of 10. The right solution for this would be to cache mappings for buffers per consumer device, but that's a bit involved. Instead, we simply revert to the old behaviour of sharing IOVA mappings when we know that devices can do so (i.e. they share the same IOMMU domain). Cc: <stable@vger.kernel.org> # v5.5 Reported-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> |
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| .. | ||
| hw | ||
| bus.c | ||
| bus.h | ||
| cdma.c | ||
| cdma.h | ||
| channel.c | ||
| channel.h | ||
| debug.c | ||
| debug.h | ||
| dev.c | ||
| dev.h | ||
| intr.c | ||
| intr.h | ||
| job.c | ||
| job.h | ||
| Kconfig | ||
| Makefile | ||
| mipi.c | ||
| syncpt.c | ||
| syncpt.h | ||