diff options
| author | Xinliang Liu <xinliang.liu@linaro.org> | 2017-02-15 17:19:08 +0100 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2017-02-26 22:11:37 +0100 |
| commit | 5f15257689bfaacfc1ecd7d91a2e0515a5d3d104 (patch) | |
| tree | d2d9814c69e62d8322f3551183a96a9a71420156 /drivers | |
| parent | cd2523569a733d85788b6fc016e4e23cb3549a25 (diff) | |
drm/fb-helper: Add multi buffer support for cma fbdev
This patch add a config to support to create multi buffer for cma fbdev.
Such as double buffer and triple buffer.
Cma fbdev is convient to add a legency fbdev. And still many Android
devices use fbdev now and at least double buffer is needed for these
Android devices, so that a buffer flip can be operated. It will need
some time for Android device vendors to abondon legency fbdev. So multi
buffer for fbdev is needed.
Signed-off-by: Xinliang Liu <xinliang.liu@linaro.org>
[s.christ@phytec.de: Picking patch from
https://lkml.org/lkml/2015/9/14/188]
Signed-off-by: Stefan Christ <s.christ@phytec.de>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/075ffb50cc16ab055b5d47b30163401bb356ab51.1487175046.git-series.maxime.ripard@free-electrons.com
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_fb_helper.c | 10 |
2 files changed, 19 insertions, 0 deletions
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index 88e01e08e279..78d7fc0ebb57 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -99,6 +99,15 @@ config DRM_FBDEV_EMULATION If in doubt, say "Y". +config DRM_FBDEV_OVERALLOC + int "Overallocation of the fbdev buffer" + depends on DRM_FBDEV_EMULATION + default 100 + help + Defines the fbdev buffer overallocation in percent. Default + is 100. Typical values for double buffering will be 200, + triple buffering 300. + config DRM_LOAD_EDID_FIRMWARE bool "Allow to specify an EDID data set instead of probing for it" depends on DRM_KMS_HELPER diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 0dd5da8c55e5..1b068e6264d5 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -48,6 +48,12 @@ module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600); MODULE_PARM_DESC(fbdev_emulation, "Enable legacy fbdev emulation [default=true]"); +static int drm_fbdev_overalloc = CONFIG_DRM_FBDEV_OVERALLOC; +module_param(drm_fbdev_overalloc, int, 0444); +MODULE_PARM_DESC(drm_fbdev_overalloc, + "Overallocation of the fbdev buffer (%) [default=" + __MODULE_STRING(CONFIG_DRM_FBDEV_OVERALLOC) "]"); + static LIST_HEAD(kernel_fb_helper_list); static DEFINE_MUTEX(kernel_fb_helper_lock); @@ -1578,6 +1584,10 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, sizes.fb_height = sizes.surface_height = 768; } + /* Handle our overallocation */ + sizes.surface_height *= drm_fbdev_overalloc; + sizes.surface_height /= 100; + /* push down into drivers */ ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes); if (ret < 0) |