[Intel-gfx] [PATCH 1/4] drm/i915: Fix cdclk bypass freq readout for tgl/bxt/glk

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

On tgl/bxt/glk the cdclk bypass frequency depends on the PLL
reference clock. So let's read out the ref clock before we
try to compute the bypass clock.

Cc: Matt Roper <matthew.d.roper at intel.com>
Fixes: 71dc367e2bc3 ("drm/i915: Consolidate bxt/cnl/icl cdclk readout")
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_cdclk.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
index 618a93bad0a8..6b75d2a91cd9 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.c
@@ -1351,6 +1351,8 @@ static void bxt_get_cdclk(struct drm_i915_private *dev_priv,
 	u32 divider;
 	int div;
 
+	bxt_de_pll_readout(dev_priv, cdclk_state);
+
 	if (INTEL_GEN(dev_priv) >= 12)
 		cdclk_state->bypass = cdclk_state->ref / 2;
 	else if (INTEL_GEN(dev_priv) >= 11)
@@ -1358,7 +1360,6 @@ static void bxt_get_cdclk(struct drm_i915_private *dev_priv,
 	else
 		cdclk_state->bypass = cdclk_state->ref;
 
-	bxt_de_pll_readout(dev_priv, cdclk_state);
 	if (cdclk_state->vco == 0) {
 		cdclk_state->cdclk = cdclk_state->bypass;
 		goto out;
-- 
2.21.0