The dma-mapping framework needs a IOMMU mapping to be created for the device which allocates/maps/frees the non-contig buffer. In the DRM framework, a gem buffer is created by the DRM virtual device and not directly by any of the physical devices (FIMD, HDMI etc). Each gem object can be set as a framebuffer to one or many of the drm devices. So a gem object cannot be allocated for any one device. All the DRM devices should be able to access this buffer. The proposed method is to create a common IOMMU mapping during drm init. This mapping is then attached to all of the drm devices including the drm device. [PATCH 1/7] drm/exynos: create common IOMMU mapping for DRM During the probe of drm fimd, the driver retrieves a 'sysmmu' field in the device node for fimd. If such a field exists, the driver retrieves the platform device of the sysmmu device. This sysmmu is set as the sysmmu for fimd. The common mapping created is then attached to fimd. This needs to be done for all the other devices (hdmi, vidi etc). [PATCH 2/7] ARM: EXYNOS5: add sysmmu field to fimd device node [PATCH 3/7] drm/exynos: add IOMMU support to drm fimd During DRM's probe which happens last, the common mapping is set to its archdata and iommu ops are set as its dma ops. This requires a modification in the dma-mapping framework so that the iommu ops can be visible to all drivers. [PATCH 4/7] ARM: dma-mapping: rename and export iommu_ops [PATCH 5/7] drm/exynos: attach drm device with common drm mapping Currently allocation and free use the iommu framework by calling dma_alloc_writecombine and dma_free_writecombine respectively. For mapping the buffers to user space, the mmap functions assume that the buffer is contiguous. This is modified by calling dma_mmap_writecombine. [PATCH 6/7] drm/exynos: Add exynos drm specific fb_mmap function [PATCH 7/7] Add IOMMU support for mapping gem object The device tree based patches are based on Leela's patch which was posted last week for adding DT support to DRM FIMD. The patch to add sysmmu field is for reference only and will be posted to the device tree mailing list. Same with the rename and export iommu_ops patch. These patches are tested on Exynos5250 SMDK board and tested with modetest from libdrm tests. Prathyush K (7): drm/exynos: create common IOMMU mapping for DRM ARM: EXYNOS5: add sysmmu field to fimd device node drm/exynos: add IOMMU support to drm fimd ARM: dma-mapping: rename and export iommu_ops drm/exynos: attach drm device with common drm mapping drm/exynos: Add exynos drm specific fb_mmap function drm/exynos: Add IOMMU support for mapping gem object arch/arm/boot/dts/exynos5250.dtsi | 1 + arch/arm/include/asm/dma-mapping.h | 1 + arch/arm/mm/dma-mapping.c | 5 ++- drivers/gpu/drm/exynos/exynos_drm_core.c | 3 ++ drivers/gpu/drm/exynos/exynos_drm_drv.c | 30 ++++++++++++++++ drivers/gpu/drm/exynos/exynos_drm_drv.h | 10 +++++ drivers/gpu/drm/exynos/exynos_drm_fbdev.c | 16 ++++++++ drivers/gpu/drm/exynos/exynos_drm_fimd.c | 54 ++++++++++++++++++++++++++++- drivers/gpu/drm/exynos/exynos_drm_gem.c | 35 ++++++++---------- 9 files changed, 133 insertions(+), 22 deletions(-) _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
