From: Paulo Zanoni <[email protected]> We first set the threshold value when we're allocating the CFB, and then later at {ilk,gen7}_fbc_enable() we increment it in case we're using 16bpp. While that is correct, it is dangerous: if we rework the code a little bit in a way that allows us to call intel_fbc_enable() without necessarily calling i915_gem_stolen_setup_compression() first, we might end up incrementing threshold more than once. To prevent that, increment a temporary variable instead.
We're going to need this patch for a later rework. Signed-off-by: Paulo Zanoni <[email protected]> --- drivers/gpu/drm/i915/intel_fbc.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c index 5270dc4..1b10b06 100644 --- a/drivers/gpu/drm/i915/intel_fbc.c +++ b/drivers/gpu/drm/i915/intel_fbc.c @@ -187,14 +187,15 @@ static void ilk_fbc_enable(struct drm_crtc *crtc) struct drm_i915_gem_object *obj = intel_fb_obj(fb); struct intel_crtc *intel_crtc = to_intel_crtc(crtc); u32 dpfc_ctl; + int threshold = dev_priv->fbc.threshold; dev_priv->fbc.enabled = true; dpfc_ctl = DPFC_CTL_PLANE(intel_crtc->plane); if (drm_format_plane_cpp(fb->pixel_format, 0) == 2) - dev_priv->fbc.threshold++; + threshold++; - switch (dev_priv->fbc.threshold) { + switch (threshold) { case 4: case 3: dpfc_ctl |= DPFC_CTL_LIMIT_4X; @@ -258,14 +259,15 @@ static void gen7_fbc_enable(struct drm_crtc *crtc) struct drm_i915_gem_object *obj = intel_fb_obj(fb); struct intel_crtc *intel_crtc = to_intel_crtc(crtc); u32 dpfc_ctl; + int threshold = dev_priv->fbc.threshold; dev_priv->fbc.enabled = true; dpfc_ctl = IVB_DPFC_CTL_PLANE(intel_crtc->plane); if (drm_format_plane_cpp(fb->pixel_format, 0) == 2) - dev_priv->fbc.threshold++; + threshold++; - switch (dev_priv->fbc.threshold) { + switch (threshold) { case 4: case 3: dpfc_ctl |= DPFC_CTL_LIMIT_4X; -- 2.1.3 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
