Because the HDLCD lacks a hardware counter for vsync signal, the DRM framework expects that the vsync interrupts are left running to feed the internal software counter. Currently the HDLCD is masking/unmasking the vsync interrupt on vblank enable/disable calls, which break that expectation. Fix that. Signed-off-by: Liviu Dudau <Liviu.Dudau@xxxxxxx> --- drivers/gpu/drm/arm/hdlcd_drv.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/arm/hdlcd_drv.c b/drivers/gpu/drm/arm/hdlcd_drv.c index fb172d2..3f92dfa 100644 --- a/drivers/gpu/drm/arm/hdlcd_drv.c +++ b/drivers/gpu/drm/arm/hdlcd_drv.c @@ -183,9 +183,13 @@ static int hdlcd_irq_postinstall(struct drm_device *drm) /* enable debug interrupts */ irq_mask |= HDLCD_DEBUG_INT_MASK; +#endif + + /* enable vsync interrupts */ + irq_mask |= HDLCD_INTERRUPT_VSYNC; hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, irq_mask); -#endif + return 0; } @@ -208,20 +212,11 @@ static void hdlcd_irq_uninstall(struct drm_device *drm) static int hdlcd_enable_vblank(struct drm_device *drm, unsigned int crtc) { - struct hdlcd_drm_private *hdlcd = drm->dev_private; - unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK); - - hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask | HDLCD_INTERRUPT_VSYNC); - return 0; } static void hdlcd_disable_vblank(struct drm_device *drm, unsigned int crtc) { - struct hdlcd_drm_private *hdlcd = drm->dev_private; - unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK); - - hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask & ~HDLCD_INTERRUPT_VSYNC); } #ifdef CONFIG_DEBUG_FS -- 2.8.2 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel