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

Damien Lespiau
2014-09-04T11:28:37Z

From: Pradeep Bhat <pradeep.bhat@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@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@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