diff options
authorFabio Estevam <fabio.estevam@nxp.com>2017-02-02 19:26:38 -0200
committerDave Airlie <airlied@redhat.com>2017-03-10 11:11:06 +1000
commitd42986b6c600da4215973878f1c889cdabbdd122 (patch)
parent7ad7a5acfb96215216f46b9848bd2d341663358f (diff)
drm: mxsfb_crtc: Fix the framebuffer misplacement
Currently the framebuffer content is displayed with incorrect offsets in both the vertical and horizontal directions. The fbdev version of the driver does not show this problem. Breno Lima dumped the eLCDIF controller registers on both the drm and fbdev drivers and noticed that the VDCTRL3 register is configured incorrectly in the drm driver. The fbdev driver calculates the vertical and horizontal wait counts of the VDCTRL3 register by doing: back porch + sync length. Looking at the horizontal and vertical timing diagram from include/drm/drm_modes.h this value corresponds to: crtc_[hv]total - crtc_[hv]sync_start So fix the VDCTRL3 register setting accordingly so that the eLCDIF controller can properly show the framebuffer content in the correct position. Reported-by: Breno Lima <breno.lima@nxp.com> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Tested-by: Breno Lima <breno.lima@nxp.com> Tested-by: Marek Vasut <marex@denx.de> Signed-off-by: Dave Airlie <airlied@redhat.com>
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
index 165abd227436..1144e0c9e894 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
@@ -221,8 +221,8 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
mxsfb->base + LCDC_VDCTRL2);
- writel(SET_HOR_WAIT_CNT(m->crtc_hblank_end - m->crtc_hsync_end) |
- SET_VERT_WAIT_CNT(m->crtc_vblank_end - m->crtc_vsync_end),
+ writel(SET_HOR_WAIT_CNT(m->crtc_htotal - m->crtc_hsync_start) |
+ SET_VERT_WAIT_CNT(m->crtc_vtotal - m->crtc_vsync_start),
mxsfb->base + LCDC_VDCTRL3);

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