mirror of https://gitee.com/openkylin/linux.git
996f545fbb
User-space use mappable BOs notably for fences, and expects that a value update by the GPU will be immediatly visible through the user-space mapping. ARM has a property that may prevent this from happening though: memory can be mapped multiple times only if the different mappings share the same caching properties. However all the lowmem memory is already identity-mapped into the kernel with cache enabled, so when user-space requests an uncached mapping, we actually get an "undefined caching policy" one and this has strange side-effects described on Freedesktop bug 86690. To prevent this from happening, allow user-space to explicitly specify which objects should be coherent, and create such objects with the TTM_PL_FLAG_UNCACHED flag. This will make TTM allocate memory using the DMA API, which will fix the identify mapping and allow us to safely map the objects to user-space uncached. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-by: Lucas Stach <dev@lynxeye.de> Signed-off-by: Ben Skeggs <bskeggs@redhat.com> |
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| .. | ||
| Kbuild | ||
| armada_drm.h | ||
| drm.h | ||
| drm_fourcc.h | ||
| drm_mode.h | ||
| drm_sarea.h | ||
| exynos_drm.h | ||
| i810_drm.h | ||
| i915_drm.h | ||
| mga_drm.h | ||
| msm_drm.h | ||
| nouveau_drm.h | ||
| omap_drm.h | ||
| qxl_drm.h | ||
| r128_drm.h | ||
| radeon_drm.h | ||
| savage_drm.h | ||
| sis_drm.h | ||
| tegra_drm.h | ||
| via_drm.h | ||
| vmwgfx_drm.h | ||