[Intel-gfx] [PATCH 5/7] drm/i915: Decode system memory bandwidth
Kumar, Mahesh
mahesh1.kumar at intel.com
Mon Aug 29 12:35:20 UTC 2016
This patch adds support to decode system memory bandwidth
which will be used for arbitrated display memory percentage
calculation in GEN9 based system.
Signed-off-by: Kumar, Mahesh <mahesh1.kumar at intel.com>
---
drivers/gpu/drm/i915/i915_drv.c | 96 +++++++++++++++++++++++++++++++++++++++++
drivers/gpu/drm/i915/i915_drv.h | 18 ++++++++
drivers/gpu/drm/i915/i915_reg.h | 25 +++++++++++
3 files changed, 139 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 47fe072..5ece036 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -996,6 +996,96 @@ static void intel_sanitize_options(struct drm_i915_private *dev_priv)
DRM_DEBUG_DRIVER("use GPU sempahores? %s\n", yesno(i915.semaphores));
}
+static void
+intel_get_memdev_info(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = to_i915(dev);
+ uint32_t val = 0;
+ uint32_t mem_speed = 0;
+ uint8_t dram_type;
+ uint32_t dram_channel;
+ uint8_t num_channel;
+ bool rank_valid = false;
+
+ if (!IS_GEN9(dev_priv))
+ goto exit;
+
+ val = I915_READ(P_CR_MC_BIOS_REQ_0_0_0);
+ mem_speed = div_u64((uint64_t) (val & REQ_DATA_MASK) *
+ MEMORY_FREQ_MULTIPLIER, 1000);
+
+ if (mem_speed == 0)
+ goto exit;
+
+ dev_priv->memdev_info.valid = true;
+ dev_priv->memdev_info.mem_speed = mem_speed;
+ dram_type = (val >> DRAM_TYPE_SHIFT) & DRAM_TYPE_MASK;
+ dram_channel = (val >> DRAM_CHANNEL_SHIFT) & DRAM_CHANNEL_MASK;
+ num_channel = hweight32(dram_channel);
+
+ /*
+ * The lpddr3 and lpddr4 technologies can have 1-4 channels and the
+ * channels are 32bits wide; while ddr3l technologies can have 1-2
+ * channels and the channels are 64 bits wide. But SV team found that in
+ * case of single 64 bit wide DDR3L dimms two bits were set and system
+ * with two DDR3L 64bit dimm all four bits were set.
+ */
+
+ switch (dram_type) {
+ case DRAM_TYPE_LPDDR3:
+ case DRAM_TYPE_LPDDR4:
+ dev_priv->memdev_info.data_width = 4;
+ dev_priv->memdev_info.num_channel = num_channel;
+ break;
+ case DRAM_TYPE_DDR3L:
+ dev_priv->memdev_info.data_width = 8;
+ dev_priv->memdev_info.num_channel = num_channel / 2;
+ break;
+ default:
+ dev_priv->memdev_info.data_width = 4;
+ dev_priv->memdev_info.num_channel = num_channel;
+ }
+
+ /*
+ * Now read each DUNIT8/9/10/11 to check the rank of each dimms.
+ * all the dimms should have same rank as in first valid Dimm
+ */
+#define D_CR_DRP0_DUNIT_INVALID 0xFFFFFFFF
+
+ dev_priv->memdev_info.rank_valid = true;
+ if (I915_READ(D_CR_DRP0_DUNIT8) != D_CR_DRP0_DUNIT_INVALID) {
+ val = I915_READ(D_CR_DRP0_DUNIT8);
+ rank_valid = true;
+ } else if (I915_READ(D_CR_DRP0_DUNIT9) != D_CR_DRP0_DUNIT_INVALID) {
+ val = I915_READ(D_CR_DRP0_DUNIT9);
+ rank_valid = true;
+ } else if (I915_READ(D_CR_DRP0_DUNIT10) != D_CR_DRP0_DUNIT_INVALID) {
+ val = I915_READ(D_CR_DRP0_DUNIT10);
+ rank_valid = true;
+ } else if (I915_READ(D_CR_DRP0_DUNIT11) != D_CR_DRP0_DUNIT_INVALID) {
+ val = I915_READ(D_CR_DRP0_DUNIT11);
+ rank_valid = true;
+ }
+#undef D_CR_DRP0_DUNIT_INVALID
+
+ if (rank_valid) {
+ dev_priv->memdev_info.rank_valid = true;
+ dev_priv->memdev_info.rank = (val & DRAM_RANK_MASK);
+ }
+
+ DRM_DEBUG_DRIVER("valid:%s speed-%d width-%d num_channel-%d\n",
+ dev_priv->memdev_info.valid ? "true" : "false",
+ dev_priv->memdev_info.mem_speed,
+ dev_priv->memdev_info.data_width,
+ dev_priv->memdev_info.num_channel);
+ DRM_DEBUG_DRIVER("rank_valid:%s rank-%d\n",
+ dev_priv->memdev_info.rank_valid ? "true" : "false",
+ dev_priv->memdev_info.rank);
+ return;
+exit:
+ dev_priv->memdev_info.valid = false;
+}
+
/**
* i915_driver_init_hw - setup state requiring device access
* @dev_priv: device private
@@ -1099,6 +1189,12 @@ static int i915_driver_init_hw(struct drm_i915_private *dev_priv)
DRM_DEBUG_DRIVER("can't enable MSI");
}
+ /*
+ * Fill the memdev structure to get the system raw bandwidth
+ * This will be used by WM algorithm, to implement GEN9 based WA
+ */
+ intel_get_memdev_info(dev);
+
return 0;
out_ggtt:
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 77a5478..d0123f8 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2017,6 +2017,24 @@ struct drm_i915_private {
bool distrust_bios_wm;
} wm;
+ struct {
+ /*
+ * memory device info
+ * valid: memory info is valid or not
+ * mem_speed: memory freq in KHz
+ * channel_width: Channel width in bytes
+ * num_channel: total number of channels
+ * rank: 0-rank disable, 1-Single rank, 2-dual rank
+ */
+ bool valid;
+ uint32_t mem_speed;
+ uint8_t data_width;
+ uint8_t num_channel;
+ bool rank_valid;
+ uint8_t rank;
+ } memdev_info;
+
+
struct i915_runtime_pm pm;
/* Abstract the submission mechanism (legacy ringbuffer or execlists) away */
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index a29d707..b38445c 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7716,6 +7716,31 @@ enum {
#define DC_STATE_DEBUG_MASK_CORES (1<<0)
#define DC_STATE_DEBUG_MASK_MEMORY_UP (1<<1)
+#define P_CR_MC_BIOS_REQ_0_0_0 _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x7114)
+#define REQ_DATA_MASK (0x3F << 0)
+#define DRAM_TYPE_SHIFT 24
+#define DRAM_TYPE_MASK 0x7
+#define DRAM_CHANNEL_SHIFT 12
+#define DRAM_CHANNEL_MASK 0xF
+
+#define DRAM_TYPE_LPDDR3 0x1
+#define DRAM_TYPE_LPDDR4 0x2
+#define DRAM_TYPE_DDR3L 0x4
+/*
+ * BIOS programs this field of REQ_DATA [5:0] in integer
+ * multiple of 133330 KHz (133.33MHz)
+ */
+#define MEMORY_FREQ_MULTIPLIER 0x208D2
+#define D_CR_DRP0_DUNIT8 _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x1000)
+#define D_CR_DRP0_DUNIT9 _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x1200)
+#define D_CR_DRP0_DUNIT10 _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x1400)
+#define D_CR_DRP0_DUNIT11 _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x1600)
+#define D_CR_DRP0_RKEN0 (1 << 0)
+#define D_CR_DRP0_RKEN1 (1 << 1)
+#define DRAM_RANK_MASK 0x3
+#define DRAM_SINGLE_RANK 0x1
+#define DRAM_DUAL_RANK 0x3
+
/* Please see hsw_read_dcomp() and hsw_write_dcomp() before using this register,
* since on HSW we can't write to it using I915_WRITE. */
#define D_COMP_HSW _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5F0C)
--
2.8.3
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