Re: [PATCH v2] drm/meson: Fix atomic mode switching regression
From: Neil Armstrong
Date: Mon Jan 28 2019 - 11:21:20 EST
Hi Stable kernel team,
On 14/01/2019 16:31, Neil Armstrong wrote:
> Since commit 2bcd3ecab773 when switching mode from X11 (ubuntu mate for
> example) the display gets blurry, looking like an invalid framebuffer width.
>
> This commit fixed atomic crtc modesetting in a totally wrong way and
> introduced a local unnecessary ->enabled crtc state.
>
> This commit reverts the crctc _begin() and _enable() changes and simply
> adds drm_atomic_helper_commit_tail_rpm as helper.
>
> Reported-by: Tony McKahan <tonymckahan@xxxxxxxxx>
> Suggested-by: Daniel Vetter <daniel@xxxxxxxx>
> Fixes: 2bcd3ecab773 ("drm/meson: Fixes for drm_crtc_vblank_on/off support")
> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
This fix has landed in linus master with id ce0210c12433031aba3bbacd75f4c02ab77f2004
could it be applied to 4.19 and 4.20 stable trees ?
Thanks,
Neil
> ---
> drivers/gpu/drm/meson/meson_crtc.c | 23 ++---------------------
> drivers/gpu/drm/meson/meson_drv.c | 6 ++++++
> 2 files changed, 8 insertions(+), 21 deletions(-)
>
> Changes since v1:
> - drop the unecessary local ->enabled logic
> - use drm_atomic_helper_commit_tail_rpm as atomic_commit_tail helper
>
> diff --git a/drivers/gpu/drm/meson/meson_crtc.c b/drivers/gpu/drm/meson/meson_crtc.c
> index 75d97f1b2e8f..4f5c67f70c4d 100644
> --- a/drivers/gpu/drm/meson/meson_crtc.c
> +++ b/drivers/gpu/drm/meson/meson_crtc.c
> @@ -46,7 +46,6 @@ struct meson_crtc {
> struct drm_crtc base;
> struct drm_pending_vblank_event *event;
> struct meson_drm *priv;
> - bool enabled;
> };
> #define to_meson_crtc(x) container_of(x, struct meson_crtc, base)
>
> @@ -82,7 +81,8 @@ static const struct drm_crtc_funcs meson_crtc_funcs = {
>
> };
>
> -static void meson_crtc_enable(struct drm_crtc *crtc)
> +static void meson_crtc_atomic_enable(struct drm_crtc *crtc,
> + struct drm_crtc_state *old_state)
> {
> struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
> struct drm_crtc_state *crtc_state = crtc->state;
> @@ -108,20 +108,6 @@ static void meson_crtc_enable(struct drm_crtc *crtc)
>
> drm_crtc_vblank_on(crtc);
>
> - meson_crtc->enabled = true;
> -}
> -
> -static void meson_crtc_atomic_enable(struct drm_crtc *crtc,
> - struct drm_crtc_state *old_state)
> -{
> - struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
> - struct meson_drm *priv = meson_crtc->priv;
> -
> - DRM_DEBUG_DRIVER("\n");
> -
> - if (!meson_crtc->enabled)
> - meson_crtc_enable(crtc);
> -
> priv->viu.osd1_enabled = true;
> }
>
> @@ -153,8 +139,6 @@ static void meson_crtc_atomic_disable(struct drm_crtc *crtc,
>
> crtc->state->event = NULL;
> }
> -
> - meson_crtc->enabled = false;
> }
>
> static void meson_crtc_atomic_begin(struct drm_crtc *crtc,
> @@ -163,9 +147,6 @@ static void meson_crtc_atomic_begin(struct drm_crtc *crtc,
> struct meson_crtc *meson_crtc = to_meson_crtc(crtc);
> unsigned long flags;
>
> - if (crtc->state->enable && !meson_crtc->enabled)
> - meson_crtc_enable(crtc);
> -
> if (crtc->state->event) {
> WARN_ON(drm_crtc_vblank_get(crtc) != 0);
>
> diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c
> index 3ee4d4a4ecba..a74d861ddceb 100644
> --- a/drivers/gpu/drm/meson/meson_drv.c
> +++ b/drivers/gpu/drm/meson/meson_drv.c
> @@ -75,6 +75,11 @@ static const struct drm_mode_config_funcs meson_mode_config_funcs = {
> .fb_create = drm_gem_fb_create,
> };
>
> +
> +static const struct drm_mode_config_helper_funcs meson_mode_config_helpers = {
> + .atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
> +};
> +
> static irqreturn_t meson_irq(int irq, void *arg)
> {
> struct drm_device *dev = arg;
> @@ -266,6 +271,7 @@ static int meson_drv_bind_master(struct device *dev, bool has_components)
> drm->mode_config.max_width = 3840;
> drm->mode_config.max_height = 2160;
> drm->mode_config.funcs = &meson_mode_config_funcs;
> + drm->mode_config.helper_private = &meson_mode_config_helpers;
>
> /* Hardware Initialization */
>
>