On Wed, Sep 16, 2015 at 5:48 AM, Xinliang Liu <xinliang.liu@xxxxxxxxxx> wrote: > > > On 16 September 2015 at 02:25, Rob Herring <robh@xxxxxxxxxx> wrote: > Hi Rob, thanks a lot for reply:-) > >> On 09/15/2015 04:37 AM, Xinwei Kong wrote: >> > If you config DRM_HISI_FBDEV optional, this patch will only support >> > fbdev >> > mode while also supporting double buffer. >> >> This is a lot of duplicated code from CMA fbdev. Is double buffering the >> only reason why CMA fbdev can't be used or are there some other >> constraints? > > Yes, double buffering is the main reason we rewrite our own fbdev. > CMA fbdev only create one buffer. But we need at least double buffer for > running Android with fbdev. > >> Double buffering in fbdev has always been a hack, so I'm >> guessing that is not a feature that should be added here. >> > If so, I think it is hard to be accepted for my cma fbdev patch to support > multi buffer. > This early week, I have sent a cma fbdev patch for supporting this. The > subject is > "[PATCH] drm/cma-helper: Add multi buffer support for cma fbdev". > We do have a strong will to support this feature. I described the reason in > the patch. Please take a look for me. Thank you very much. fwiw, drm_gralloc has support for kms. Currently it is expected to be paired w/ a mesa gpu driver, which might not work for everyone, but I suppose the display part of it could be extracted out for a gralloc.kms.so for pure sw rendering.. that might be a better approach. http://git.android-x86.org/?p=platform/hardware/drm_gralloc.git BR, -R > -Xinliang > >> Rob >> >> > Signed-off-by: Xinliang Liu <xinliang.liu@xxxxxxxxxx> >> > Signed-off-by: Xinwei Kong <kong.kongxinwei@xxxxxxxxxxxxx> >> > Signed-off-by: Andy Green <andy.green@xxxxxxxxxx> >> > Signed-off-by: Jiwen Qi <qijiwen@xxxxxxxxxxxxx> >> > Signed-off-by: Yu Gong <gongyu@xxxxxxxxxxxxx> >> > --- >> > drivers/gpu/drm/hisilicon/Kconfig | 13 + >> > drivers/gpu/drm/hisilicon/Makefile | 3 +- >> > drivers/gpu/drm/hisilicon/hisi_drm_connector.c | 4 + >> > drivers/gpu/drm/hisilicon/hisi_drm_drv.c | 9 + >> > drivers/gpu/drm/hisilicon/hisi_drm_dsi.c | 15 + >> > drivers/gpu/drm/hisilicon/hisi_drm_fb.h | 5 + >> > drivers/gpu/drm/hisilicon/hisi_drm_fbdev.c | 395 >> > +++++++++++++++++++++++++ >> > drivers/gpu/drm/hisilicon/hisi_drm_fbdev.h | 24 ++ >> > 8 files changed, 467 insertions(+), 1 deletion(-) >> > create mode 100644 drivers/gpu/drm/hisilicon/hisi_drm_fbdev.c >> > create mode 100644 drivers/gpu/drm/hisilicon/hisi_drm_fbdev.h >> > > > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/dri-devel > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
