From d31faf65b8300fa120f4b31d90270fbac36fc779 Mon Sep 17 00:00:00 2001 From: Ville Syrjälä Date: Mon, 28 Oct 2013 16:31:41 +0200 Subject: drm/i915: Fix scanoutpos calculations for interlaced modes The scanline counter counts lines in the current field, not the entire frame. But the crtc_ timings are the values for the entire frame. Divide the vertical timings by 2 to make them match the scanline counter. The rounding was carefully chosen to make it do the right thing wrt. the observed scanline counter and ISR vblank bit behaviour. Reviewed-by: mario.kleiner.de@gmail.com Signed-off-by: Ville Syrjälä --- drivers/gpu/drm/i915/i915_irq.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers') diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index b6e4a762806b..eacbb2f9e091 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -698,6 +698,12 @@ static int i915_get_crtc_scanoutpos(struct drm_device *dev, int pipe, vbl_start = mode->crtc_vblank_start; vbl_end = mode->crtc_vblank_end; + if (mode->flags & DRM_MODE_FLAG_INTERLACE) { + vbl_start = DIV_ROUND_UP(vbl_start, 2); + vbl_end /= 2; + vtotal /= 2; + } + ret |= DRM_SCANOUTPOS_VALID | DRM_SCANOUTPOS_ACCURATE; /* -- cgit v1.2.3-55-g7522