Currently, the vblank support is not correctly implemented in MXSFB_DRM driver. The call to drm_vblank_init is made with mode_config.num_crtc which at that time is 0. Because of this, vblank is not activated, so there won't be any vblank event submitted. For example, when running modetest with the '-v' parameter will result in an astronomical refresh rate (10000+ Hz), because of that.
Signed-off-by: Robert Chiras robert.chiras@nxp.com --- drivers/gpu/drm/mxsfb/mxsfb_drv.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c b/drivers/gpu/drm/mxsfb/mxsfb_drv.c index 2743975..829abec 100644 --- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c +++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c @@ -38,6 +38,9 @@ #include "mxsfb_drv.h" #include "mxsfb_regs.h"
+/* The eLCDIF max possible CRTCs */ +#define MAX_CRTCS 1 + enum mxsfb_devtype { MXSFB_V3, MXSFB_V4, @@ -138,6 +141,8 @@ static void mxsfb_pipe_enable(struct drm_simple_display_pipe *pipe, mxsfb->connector = &mxsfb->panel_connector; }
+ drm_crtc_vblank_on(&pipe->crtc); + pm_runtime_get_sync(drm->dev); drm_panel_prepare(mxsfb->panel); mxsfb_crtc_enable(mxsfb); @@ -164,6 +169,8 @@ static void mxsfb_pipe_disable(struct drm_simple_display_pipe *pipe) } spin_unlock_irq(&drm->event_lock);
+ drm_crtc_vblank_off(&pipe->crtc); + if (mxsfb->connector != &mxsfb->panel_connector) mxsfb->connector = NULL; } @@ -246,7 +253,7 @@ static int mxsfb_load(struct drm_device *drm, unsigned long flags)
pm_runtime_enable(drm->dev);
- ret = drm_vblank_init(drm, drm->mode_config.num_crtc); + ret = drm_vblank_init(drm, MAX_CRTCS); if (ret < 0) { dev_err(drm->dev, "Failed to initialise vblank\n"); goto err_vblank; @@ -269,6 +276,8 @@ static int mxsfb_load(struct drm_device *drm, unsigned long flags) goto err_vblank; }
+ drm_crtc_vblank_off(&mxsfb->pipe.crtc); + /* * Attach panel only if there is one. * If there is no panel attach, it must be a bridge. In this case, we