Re: [PATCH] drm/mediatek: crtc: Make config-updating atomic

While updating config, the irq would occur and get the partial
config, so use variable config_updating to make updating atomic.

Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
---
 drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index 8b0de90156c6..870f66210848 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c

@@ -61,6 +61,7 @@ struct mtk_drm_crtc {

        /* lock for display hardware access */
        struct mutex                    hw_lock;
+       bool                            config_updating;
 };

 struct mtk_crtc_state {

@@ -97,7 +98,7 @@ static void mtk_drm_crtc_finish_page_flip(struct mtk_drm_crtc *mtk_crtc)
 static void mtk_drm_finish_page_flip(struct mtk_drm_crtc *mtk_crtc)
 {
        drm_crtc_handle_vblank(&mtk_crtc->base);
-       if (mtk_crtc->pending_needs_vblank) {
+       if (!mtk_crtc->config_updating && mtk_crtc->pending_needs_vblank) {
                mtk_drm_crtc_finish_page_flip(mtk_crtc);
                mtk_crtc->pending_needs_vblank = false;
        }

@@ -425,7 +426,8 @@ static void mtk_crtc_ddp_config(struct drm_crtc *crtc,
        }
 }

-static void mtk_drm_crtc_hw_config(struct mtk_drm_crtc *mtk_crtc)
+static void mtk_drm_crtc_update_config(struct mtk_drm_crtc *mtk_crtc,
+                                      bool needs_vblank)
 {
 #if IS_REACHABLE(CONFIG_MTK_CMDQ)
        struct cmdq_pkt *cmdq_handle;

@@ -436,6 +438,10 @@ static void mtk_drm_crtc_hw_config(struct mtk_drm_crtc *mtk_crtc)
        int i;

        mutex_lock(&mtk_crtc->hw_lock);
+       mtk_crtc->config_updating = true;
+       if (needs_vblank)
+               mtk_crtc->pending_needs_vblank = true;
+
        for (i = 0; i < mtk_crtc->layer_nr; i++) {
                struct drm_plane *plane = &mtk_crtc->planes[i];
                struct mtk_plane_state *plane_state;

@@ -472,6 +478,7 @@ static void mtk_drm_crtc_hw_config(struct mtk_drm_crtc *mtk_crtc)
                cmdq_pkt_flush_async(cmdq_handle, ddp_cmdq_cb, cmdq_handle);
        }
 #endif
+       mtk_crtc->config_updating = false;
        mutex_unlock(&mtk_crtc->hw_lock);
 }

@@ -532,7 +539,7 @@ void mtk_drm_crtc_async_update(struct drm_crtc *crtc, struct drm_plane *plane,
                return;

        plane_helper_funcs->atomic_update(plane, new_state);
-       mtk_drm_crtc_hw_config(mtk_crtc);
+       mtk_drm_crtc_update_config(mtk_crtc, false);
 }

 static void mtk_drm_crtc_atomic_enable(struct drm_crtc *crtc,

@@ -582,7 +589,7 @@ static void mtk_drm_crtc_atomic_disable(struct drm_crtc *crtc,
        }
        mtk_crtc->pending_planes = true;

-       mtk_drm_crtc_hw_config(mtk_crtc);
+       mtk_drm_crtc_update_config(mtk_crtc, false);
        /* Wait for planes to be disabled */
        drm_crtc_wait_one_vblank(crtc);

@@ -618,14 +625,12 @@ static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc,
        struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
        int i;

-       if (mtk_crtc->event)
-               mtk_crtc->pending_needs_vblank = true;
        if (crtc->state->color_mgmt_changed)
                for (i = 0; i < mtk_crtc->ddp_comp_nr; i++) {
                        mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], crtc->state);
                        mtk_ddp_ctm_set(mtk_crtc->ddp_comp[i], crtc->state);
                }
-       mtk_drm_crtc_hw_config(mtk_crtc);
+       mtk_drm_crtc_update_config(mtk_crtc, !!mtk_crtc->event);
 }

 static const struct drm_crtc_funcs mtk_crtc_funcs = {
--

2.17.1