From: Ville Syrjälä <[email protected]> free_pos is in dwords, DSB_BUF_SIZE in bytes. Directly comparing the two is nonsense. Fix it up, and make sure we also account for the 8byte alignment requirement for each instruction, and also assume that each instruction normally eats two dwords.
Signed-off-by: Ville Syrjälä <[email protected]> --- drivers/gpu/drm/i915/display/intel_dsb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c index 6abfd0fc541a..fbcbf9efd039 100644 --- a/drivers/gpu/drm/i915/display/intel_dsb.c +++ b/drivers/gpu/drm/i915/display/intel_dsb.c @@ -97,7 +97,7 @@ void intel_dsb_indexed_reg_write(struct intel_dsb *dsb, u32 *buf = dsb->cmd_buf; u32 reg_val; - if (drm_WARN_ON(&dev_priv->drm, dsb->free_pos >= DSB_BUF_SIZE)) { + if (drm_WARN_ON(&dev_priv->drm, ALIGN(dsb->free_pos, 2) > DSB_BUF_SIZE / 4 - 2)) { drm_dbg_kms(&dev_priv->drm, "DSB buffer overflow\n"); return; } @@ -167,7 +167,7 @@ void intel_dsb_reg_write(struct intel_dsb *dsb, struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); u32 *buf = dsb->cmd_buf; - if (drm_WARN_ON(&dev_priv->drm, dsb->free_pos >= DSB_BUF_SIZE)) { + if (drm_WARN_ON(&dev_priv->drm, ALIGN(dsb->free_pos, 2) > DSB_BUF_SIZE / 4 - 2)) { drm_dbg_kms(&dev_priv->drm, "DSB buffer overflow\n"); return; } -- 2.37.4
