DRM client buffers are permanently mapped throughout their lifetime. This prevents us from using generic framebuffer emulation for devices with small dedicated video memory, such as ast or mgag200. With fb buffers permanently mapped, such devices often won't have enougth space left to display other content (e.g., X11). This patch set introduces unmappable DRM client buffers for framebuffer emulation with shadow buffers. While the shadow buffer remains in system memory permanently, the respective buffer object will only be mapped briefly during updates from the shadow buffer. Hence, the driver can relocate he buffer object among memory regions as needed. The default behoviour for DRM client buffers is still to be permanently mapped. The patch set converts ast and mgag200 to generic framebuffer emulation and removes a large amount of framebuffer code from these drivers. For bochs, a problem was reported where the driver could not display the console because it was pinned in system memory. [1] The patch set fixes this bug by converting bochs to use the shadow fb. The patch set has been tested on ast and mga200 HW. [1] https://lists.freedesktop.org/archives/dri-devel/2019-June/224423.html Thomas Zimmermann (5): drm/client: Support unmapping of DRM client buffers drm/fb-helper: Unmap BO for shadow-buffered framebuffer console drm/ast: Replace struct ast_fbdev with generic framebuffer emulation drm/bochs: Use shadow buffer for bochs framebuffer console drm/mgag200: Replace struct mga_fbdev with generic framebuffer emulation drivers/gpu/drm/ast/Makefile | 2 +- drivers/gpu/drm/ast/ast_drv.c | 22 +- drivers/gpu/drm/ast/ast_drv.h | 17 -- drivers/gpu/drm/ast/ast_fb.c | 341 ------------------------- drivers/gpu/drm/ast/ast_main.c | 30 ++- drivers/gpu/drm/ast/ast_mode.c | 21 -- drivers/gpu/drm/bochs/bochs_kms.c | 2 +- drivers/gpu/drm/drm_client.c | 71 ++++- drivers/gpu/drm/drm_fb_helper.c | 14 +- drivers/gpu/drm/mgag200/Makefile | 2 +- drivers/gpu/drm/mgag200/mgag200_drv.h | 19 -- drivers/gpu/drm/mgag200/mgag200_fb.c | 309 ---------------------- drivers/gpu/drm/mgag200/mgag200_main.c | 61 +++-- drivers/gpu/drm/mgag200/mgag200_mode.c | 27 -- include/drm/drm_client.h | 3 + 15 files changed, 154 insertions(+), 787 deletions(-) delete mode 100644 drivers/gpu/drm/ast/ast_fb.c delete mode 100644 drivers/gpu/drm/mgag200/mgag200_fb.c -- 2.21.0 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
