| Message ID | 20220215165226.2738568-1-geert@linux-m68k.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | drm: Add support for low-color frame buffer formats | expand |
Hi Geert, On Tue, Feb 15, 2022 at 05:52:18PM +0100, Geert Uytterhoeven wrote: > Hi all, > > A long outstanding issue with the DRM subsystem has been the lack of > support for low-color displays, as used typically on older desktop > systems and small embedded displays. This is one of the pieces missing for a long time - great to see something done here. Thanks Geert! Sam
Am 17.02.22 um 21:37 schrieb Sam Ravnborg: > Hi Geert, > > On Tue, Feb 15, 2022 at 05:52:18PM +0100, Geert Uytterhoeven wrote: >> Hi all, >> >> A long outstanding issue with the DRM subsystem has been the lack of >> support for low-color displays, as used typically on older desktop >> systems and small embedded displays. > > This is one of the pieces missing for a long time - great to see > something done here. Thanks Geert! Absolutely! I'm looking forward to see these patches being merged. Best regards Thomas > > Sam
Hi all, A long outstanding issue with the DRM subsystem has been the lack of support for low-color displays, as used typically on older desktop systems and small embedded displays. This patch series adds support for color-indexed frame buffer formats with 2, 4, and 16 colors. It has been tested on ARAnyM using a work-in-progress Atari DRM driver, with text console operation and fbtest. Overview: - Patches 1 and 2 give a working system, albeit with a too large pitch (line length), - Patches 3 and 4 reduce memory consumption by correcting the pitch in case bpp < 8, - Patches 5 and 6 are untested, but may become useful with DRM userspace, - Patches 7 and 8 add more fourcc codes for grayscale and monochrome frame buffer formats, which may be useful for e.g. the ssd130x and repaper drivers. Notes: - I haven't looked yet into making modetest draw a correct image. - As this was used on emulated hardware only, and I do not have Atari hardware, I do not have performance figures to compare with fbdev. I hope to do proper measuring with an Amiga DRM driver, eventually. Thanks for your comments! Geert Uytterhoeven (8): drm/fourcc: Add DRM_FORMAT_C[124] drm/fb-helper: Add support for DRM_FORMAT_C[124] drm/fourcc: Add drm_format_info_bpp() helper drm/client: Use actual bpp when allocating frame buffers drm/framebuffer: Use actual bpp for DRM_IOCTL_MODE_GETFB drm/gem-fb-helper: Use actual bpp for size calculations drm/fourcc: Add DRM_FORMAT_R[124] drm/fourcc: Add DRM_FORMAT_D1 drivers/gpu/drm/drm_client.c | 4 +- drivers/gpu/drm/drm_fb_helper.c | 120 ++++++++++++++----- drivers/gpu/drm/drm_fourcc.c | 45 +++++++ drivers/gpu/drm/drm_framebuffer.c | 2 +- drivers/gpu/drm/drm_gem_framebuffer_helper.c | 12 +- include/drm/drm_fourcc.h | 1 + include/uapi/drm/drm_fourcc.h | 15 +++ 7 files changed, 160 insertions(+), 39 deletions(-)