[Intel-gfx] [PATCH v2] drm/i915/skl: Retrieve the Rpe value from Pcode

[akash.goel at intel.com]

From: Akash Goel <akash.goel at intel.com>

Read the efficient frequency (aka RPe) value through the the mailbox
command (0x1A) from the pcode, as done on Haswell and Broadwell.
The turbo minimum frequency softlimit is not revised as per the
efficient frequency value.

v2: Replaced the conditional expression operator with 'if' statement (Tom)

Issue: VIZ-5143
Signed-off-by: Akash Goel <akash.goel at intel.com>
---
 drivers/gpu/drm/i915/intel_pm.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index d091fec..21b22a7 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4314,16 +4314,20 @@ static void gen6_init_rps_frequencies(struct drm_device *dev)
 	dev_priv->rps.max_freq		= dev_priv->rps.rp0_freq;
 
 	dev_priv->rps.efficient_freq = dev_priv->rps.rp1_freq;
-	if (IS_HASWELL(dev) || IS_BROADWELL(dev)) {
+	if (IS_HASWELL(dev) || IS_BROADWELL(dev) || IS_SKYLAKE(dev)) {
 		ret = sandybridge_pcode_read(dev_priv,
 					HSW_PCODE_DYNAMIC_DUTY_CYCLE_CONTROL,
 					&ddcc_status);
-		if (0 == ret)
+		if (0 == ret) {
 			dev_priv->rps.efficient_freq =
 				clamp_t(u8,
 					((ddcc_status >> 8) & 0xff),
 					dev_priv->rps.min_freq,
 					dev_priv->rps.max_freq);
+
+			if (IS_SKYLAKE(dev))
+			      dev_priv->rps.efficient_freq *= GEN9_FREQ_SCALER;
+		}
 	}
 
 	dev_priv->rps.idle_freq = dev_priv->rps.min_freq;
-- 
1.9.2