LCDIF will repeatedly display data from CUR_BUF and set CUR_BUF to NEXT_BUF when done. Since we are only ever writing to NEXT_BUF the display will show an initial corrupt frame.
Fix by writing the FB paddr to both CUR_BUF and NEXT_BUF when activating the CRTC.
Signed-off-by: Leonard Crestez leonard.crestez@nxp.com Tested-by: Philipp Zabel p.zabel@pengutronix.de --- drivers/gpu/drm/mxsfb/mxsfb_crtc.c | 45 +++++++++++++++++++++--------- 1 file changed, 32 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c index e4fcbb65b969..24b1f0c1432e 100644 --- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c +++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c @@ -191,10 +191,25 @@ static int mxsfb_reset_block(void __iomem *reset_addr) return ret;
return clear_poll_bit(reset_addr, MODULE_CLKGATE); }
+static dma_addr_t mxsfb_get_fb_paddr(struct mxsfb_drm_private *mxsfb) +{ + struct drm_framebuffer *fb = mxsfb->pipe.plane.state->fb; + struct drm_gem_cma_object *gem; + + if (!fb) + return 0; + + gem = drm_fb_cma_get_gem_obj(fb, 0); + if (!gem) + return 0; + + return gem->paddr; +} + static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb) { struct drm_display_mode *m = &mxsfb->pipe.crtc.state->adjusted_mode; const u32 bus_flags = mxsfb->connector.display_info.bus_flags; u32 vdctrl0, vsync_pulse_len, hsync_pulse_len; @@ -267,12 +282,22 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb) mxsfb->base + LCDC_VDCTRL4); }
void mxsfb_crtc_enable(struct mxsfb_drm_private *mxsfb) { + dma_addr_t paddr; + mxsfb_enable_axi_clk(mxsfb); mxsfb_crtc_mode_set_nofb(mxsfb); + + /* Write cur_buf as well to avoid an initial corrupt frame */ + paddr = mxsfb_get_fb_paddr(mxsfb); + if (paddr) { + writel(paddr, mxsfb->base + mxsfb->devdata->cur_buf); + writel(paddr, mxsfb->base + mxsfb->devdata->next_buf); + } + mxsfb_enable_controller(mxsfb); }
void mxsfb_crtc_disable(struct mxsfb_drm_private *mxsfb) { @@ -283,16 +308,12 @@ void mxsfb_crtc_disable(struct mxsfb_drm_private *mxsfb) void mxsfb_plane_atomic_update(struct mxsfb_drm_private *mxsfb, struct drm_plane_state *state) { struct drm_simple_display_pipe *pipe = &mxsfb->pipe; struct drm_crtc *crtc = &pipe->crtc; - struct drm_framebuffer *fb = pipe->plane.state->fb; struct drm_pending_vblank_event *event; - struct drm_gem_cma_object *gem; - - if (!crtc) - return; + dma_addr_t paddr;
spin_lock_irq(&crtc->dev->event_lock); event = crtc->state->event; if (event) { crtc->state->event = NULL; @@ -303,14 +324,12 @@ void mxsfb_plane_atomic_update(struct mxsfb_drm_private *mxsfb, drm_crtc_send_vblank_event(crtc, event); } } spin_unlock_irq(&crtc->dev->event_lock);
- if (!fb) - return; - - gem = drm_fb_cma_get_gem_obj(fb, 0); - - mxsfb_enable_axi_clk(mxsfb); - writel(gem->paddr, mxsfb->base + mxsfb->devdata->next_buf); - mxsfb_disable_axi_clk(mxsfb); + paddr = mxsfb_get_fb_paddr(mxsfb); + if (paddr) { + mxsfb_enable_axi_clk(mxsfb); + writel(paddr, mxsfb->base + mxsfb->devdata->next_buf); + mxsfb_disable_axi_clk(mxsfb); + } }