[Intel-gfx] [PATCH 43/89] drm/i915/skl: Read the Memory Latency Values for WM computation

Damien Lespiau damien.lespiau at intel.com
Thu Sep 4 13:27:09 CEST 2014


From: Pradeep Bhat <pradeep.bhat at intel.com>

This patch reads the memory latency values for all the 8 levels for
SKL. These values are needed for the Watermark computation.

v2: Incorporated the review comments from Damien on register
    indentation.

v3: Updated the code to use the sandybridge_pcode_read for reading
    memory latencies for GEN9.

v4: Don't put gen 9 in the middle of an ordered list of ifs
    (Damien)

v5 take the rps.hw_lock around sandybridge_pcode_read() (Damien)

Signed-off-by: Pradeep Bhat <pradeep.bhat at intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h |  6 ++++
 drivers/gpu/drm/i915/i915_reg.h |  9 +++++
 drivers/gpu/drm/i915/intel_pm.c | 73 +++++++++++++++++++++++++++++++++++++----
 3 files changed, 82 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index dcd1c72..32be299 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1665,6 +1665,12 @@ struct drm_i915_private {
 		uint16_t spr_latency[5];
 		/* cursor */
 		uint16_t cur_latency[5];
+		/*
+		 * Raw watermark memory latency values
+		 * for SKL for all 8 levels
+		 * in 1us units.
+		 */
+		uint16_t skl_latency[8];
 
 		/* current hardware state */
 		struct ilk_wm_values hw;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 0159f2d..bc55990 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2018,6 +2018,15 @@ enum punit_power_well {
 #define   MAD_DIMM_A_SIZE_SHIFT		0
 #define   MAD_DIMM_A_SIZE_MASK		(0xff << MAD_DIMM_A_SIZE_SHIFT)
 
+/* SKL GT Driver Mailbox registers for reading memory latencies */
+#define GEN9_MAILBOX_DATA1		0x13812C
+#define   GEN9_MAILBOX_READ_MEM_LAT	(0x6)
+#define   GEN9_MAILBOX_READ_TIMEOUT	150
+#define   GEN9_MEM_LAT_LEVEL_MASK	0xFF
+#define   GEN9_MEM_LAT_LEVEL_1_5_SHIFT	8
+#define   GEN9_MEM_LAT_LEVEL_2_6_SHIFT	16
+#define   GEN9_MEM_LAT_LEVEL_3_7_SHIFT	24
+
 /* snb MCH registers for priority tuning */
 #define MCH_SSKPD			(MCHBAR_MIRROR_BASE_SNB + 0x5d10)
 #define   MCH_SSKPD_WM0_MASK		0x3f
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index a236e77..d8c8531 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2239,11 +2239,53 @@ hsw_compute_linetime_wm(struct drm_device *dev, struct drm_crtc *crtc)
 	       PIPE_WM_LINETIME_TIME(linetime);
 }
 
-static void intel_read_wm_latency(struct drm_device *dev, uint16_t wm[5])
+static void intel_read_wm_latency(struct drm_device *dev, uint16_t wm[8])
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 
-	if (IS_HASWELL(dev) || IS_BROADWELL(dev)) {
+	if (IS_GEN9(dev)) {
+		uint32_t val;
+		int ret;
+
+		/* read the first set of memory latencies[0:3] */
+		val = 0; /* data0 to be programmed to 0 for first set */
+		mutex_lock(&dev_priv->rps.hw_lock);
+		ret = sandybridge_pcode_read(dev_priv,
+					     GEN9_MAILBOX_READ_MEM_LAT,
+					     &val);
+		mutex_unlock(&dev_priv->rps.hw_lock);
+
+		if (ret) {
+			DRM_ERROR("SKL Mailbox read error = %d\n", ret);
+			return;
+		}
+		wm[0] = val & GEN9_MEM_LAT_LEVEL_MASK;
+		wm[1] = (val >> GEN9_MEM_LAT_LEVEL_1_5_SHIFT) &
+				GEN9_MEM_LAT_LEVEL_MASK;
+		wm[2] = (val >> GEN9_MEM_LAT_LEVEL_2_6_SHIFT) &
+				GEN9_MEM_LAT_LEVEL_MASK;
+		wm[3] = (val >> GEN9_MEM_LAT_LEVEL_3_7_SHIFT) &
+				GEN9_MEM_LAT_LEVEL_MASK;
+
+		/* read the second set of memory latencies[4:7] */
+		val = 1; /* data0 to be programmed to 1 for second set */
+		mutex_lock(&dev_priv->rps.hw_lock);
+		ret = sandybridge_pcode_read(dev_priv,
+					     GEN9_MAILBOX_READ_MEM_LAT,
+					     &val);
+		mutex_unlock(&dev_priv->rps.hw_lock);
+		if (ret) {
+			DRM_ERROR("SKL Mailbox read error = %d\n", ret);
+			return;
+		}
+		wm[4] = val & GEN9_MEM_LAT_LEVEL_MASK;
+		wm[5] = (val >> GEN9_MEM_LAT_LEVEL_1_5_SHIFT) &
+				GEN9_MEM_LAT_LEVEL_MASK;
+		wm[6] = (val >> GEN9_MEM_LAT_LEVEL_2_6_SHIFT) &
+				GEN9_MEM_LAT_LEVEL_MASK;
+		wm[7] = (val >> GEN9_MEM_LAT_LEVEL_3_7_SHIFT) &
+				GEN9_MEM_LAT_LEVEL_MASK;
+	} else if (IS_HASWELL(dev) || IS_BROADWELL(dev)) {
 		uint64_t sskpd = I915_READ64(MCH_SSKPD);
 
 		wm[0] = (sskpd >> 56) & 0xFF;
@@ -2291,7 +2333,9 @@ static void intel_fixup_cur_wm_latency(struct drm_device *dev, uint16_t wm[5])
 int ilk_wm_max_level(const struct drm_device *dev)
 {
 	/* how many WM levels are we expecting */
-	if (IS_HASWELL(dev) || IS_BROADWELL(dev))
+	if (IS_GEN9(dev))
+		return 7;
+	else if (IS_HASWELL(dev) || IS_BROADWELL(dev))
 		return 4;
 	else if (INTEL_INFO(dev)->gen >= 6)
 		return 3;
@@ -2300,7 +2344,7 @@ int ilk_wm_max_level(const struct drm_device *dev)
 }
 static void intel_print_wm_latency(struct drm_device *dev,
 				   const char *name,
-				   const uint16_t wm[5])
+				   const uint16_t wm[8])
 {
 	int level, max_level = ilk_wm_max_level(dev);
 
@@ -2313,8 +2357,13 @@ static void intel_print_wm_latency(struct drm_device *dev,
 			continue;
 		}
 
-		/* WM1+ latency values in 0.5us units */
-		if (level > 0)
+		/*
+		 * - latencies are in us on gen9.
+		 * - before then, WM1+ latency values are in 0.5us units
+		 */
+		if (IS_GEN9(dev))
+			latency *= 10;
+		else if (level > 0)
 			latency *= 5;
 
 		DRM_DEBUG_KMS("%s WM%d latency %u (%u.%u usec)\n",
@@ -2382,6 +2431,14 @@ static void ilk_setup_wm_latency(struct drm_device *dev)
 		snb_wm_latency_quirk(dev);
 }
 
+static void skl_setup_wm_latency(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	intel_read_wm_latency(dev, dev_priv->wm.skl_latency);
+	intel_print_wm_latency(dev, "Gen9 Plane", dev_priv->wm.skl_latency);
+}
+
 static void ilk_compute_wm_parameters(struct drm_crtc *crtc,
 				      struct ilk_pipe_wm_parameters *p)
 {
@@ -7396,6 +7453,8 @@ void intel_init_pm(struct drm_device *dev)
 
 	/* For FIFO watermark updates */
 	if (IS_GEN9(dev)) {
+		skl_setup_wm_latency(dev);
+
 		dev_priv->display.init_clock_gating = gen9_init_clock_gating;
 	} else if (HAS_PCH_SPLIT(dev)) {
 		ilk_setup_wm_latency(dev);
@@ -7488,6 +7547,8 @@ int sandybridge_pcode_read(struct drm_i915_private *dev_priv, u8 mbox, u32 *val)
 	}
 
 	I915_WRITE(GEN6_PCODE_DATA, *val);
+	if (IS_GEN9(dev_priv->dev))
+		I915_WRITE(GEN9_MAILBOX_DATA1, 0);
 	I915_WRITE(GEN6_PCODE_MAILBOX, GEN6_PCODE_READY | mbox);
 
 	if (wait_for((I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) == 0,
-- 
1.8.3.1




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