[v3] drm/i915/skl: Retrieve the Rpe value from Pcode

Commit Message

[e-mail] June 12, 2015, 5:58 p.m. UTC

From: Akash Goel <[e-mail]>

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)
v3: Corrected the derivation of efficient frequency & shifted the
    GEN9_FREQ_SCALER multiplications downwards (Ville)

Issue: VIZ-5143
Signed-off-by: Akash Goel <[e-mail]>
---
 drivers/gpu/drm/i915/intel_pm.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

Comments

Shuang He June 28, 2015, 10:09 a.m. UTC | #1

Tested-By: Intel Graphics QA PRTS (Patch Regression Test System Contact: [e-mail])
Task id: 6601
-------------------------------------Summary-------------------------------------
Platform          Delta          drm-intel-nightly          Series Applied
ILK                                  302/302              302/302
SNB                                  312/316              312/316
IVB                                  343/343              343/343
BYT                 -1              287/287              286/287
HSW                                  380/380              380/380
-------------------------------------Detailed-------------------------------------
Platform  Test                                drm-intel-nightly          Series Applied
*BYT  igt@gem_partial_pwrite_pread@reads-display      PASS(1)      FAIL(1)
Note: You need to pay more attention to line start with '*'

Patch

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index d091fec..ff72374 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4303,18 +4303,11 @@  static void gen6_init_rps_frequencies(struct drm_device *dev)
 	dev_priv->rps.rp0_freq		= (rp_state_cap >>  0) & 0xff;
 	dev_priv->rps.rp1_freq		= (rp_state_cap >>  8) & 0xff;
 	dev_priv->rps.min_freq		= (rp_state_cap >> 16) & 0xff;
-	if (IS_SKYLAKE(dev)) {
-		/* Store the frequency values in 16.66 MHZ units, which is
-		   the natural hardware unit for SKL */
-		dev_priv->rps.rp0_freq *= GEN9_FREQ_SCALER;
-		dev_priv->rps.rp1_freq *= GEN9_FREQ_SCALER;
-		dev_priv->rps.min_freq *= GEN9_FREQ_SCALER;
-	}
 	/* hw_max = RP0 until we check for overclocking */
 	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);
@@ -4326,6 +4319,16 @@  static void gen6_init_rps_frequencies(struct drm_device *dev)
 					dev_priv->rps.max_freq);
 	}
 
+	if (IS_SKYLAKE(dev)) {
+		/* Store the frequency values in 16.66 MHZ units, which is
+		   the natural hardware unit for SKL */
+		dev_priv->rps.rp0_freq *= GEN9_FREQ_SCALER;
+		dev_priv->rps.rp1_freq *= GEN9_FREQ_SCALER;
+		dev_priv->rps.min_freq *= GEN9_FREQ_SCALER;
+		dev_priv->rps.max_freq *= GEN9_FREQ_SCALER;
+		dev_priv->rps.efficient_freq *= GEN9_FREQ_SCALER;
+	}
+
 	dev_priv->rps.idle_freq = dev_priv->rps.min_freq;
 
 	/* Preserve min/max settings in case of re-init */