drm/i915: Bump CHV PFI credits to 63 when cdclk>=czclk

Switch from using 31 PFI credits to 63 PFI credits when cdclk>=czclk on
CHV. The spec lists both 31 and 63 as "suggested" values, but based on
feedback from hardware folks we should actually be using 63. Originally
I picked the 31 basically by flipping a coin.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Clint Taylor <Clinton.A.Taylor@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Ville Syrjälä 2015-05-26 20:22:40 +03:00 committed by Daniel Vetter
parent ac3f918d5a
commit fcc0008fd0
1 changed files with 1 additions and 1 deletions

View File

@ -6055,7 +6055,7 @@ static void vlv_program_pfi_credits(struct drm_i915_private *dev_priv)
if (DIV_ROUND_CLOSEST(dev_priv->cdclk_freq, 1000) >= dev_priv->rps.cz_freq) {
/* CHV suggested value is 31 or 63 */
if (IS_CHERRYVIEW(dev_priv))
credits = PFI_CREDIT_31;
credits = PFI_CREDIT_63;
else
credits = PFI_CREDIT(15);
} else {