[Intel-gfx] [PATCH v4 3/8] drm/i915: Decode system memory bandwidth
Kumar, Mahesh
mahesh1.kumar at intel.com
Thu Oct 13 10:58:21 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.
Changes from v1:
- Address comments from Paulo
- implement decode function for SKL/KBL also
Signed-off-by: "Kumar, Mahesh" <mahesh1.kumar at intel.com>
---
drivers/gpu/drm/i915/i915_drv.c | 170 ++++++++++++++++++++++++++++++++++++++++
drivers/gpu/drm/i915/i915_drv.h | 14 ++++
drivers/gpu/drm/i915/i915_reg.h | 38 +++++++++
3 files changed, 222 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 89d3222..b5f601c 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -979,6 +979,170 @@ static void intel_sanitize_options(struct drm_i915_private *dev_priv)
DRM_DEBUG_DRIVER("use GPU sempahores? %s\n", yesno(i915.semaphores));
}
+static inline void skl_memdev_info_fill(struct memdev_info *info, uint32_t val)
+{
+ uint8_t channel_width, rank;
+
+ info->rank_valid = true;
+ channel_width = (val >> SKL_DRAM_CHANNEL_WIDTH_SHIFT) &
+ SKL_DRAM_CHANNEL_WIDTH_MASK;
+ if (channel_width == SKL_DRAM_WIDTH_1)
+ info->channel_width_bytes = 1;
+ else if (channel_width == SKL_DRAM_WIDTH_2)
+ info->channel_width_bytes = 2;
+ else
+ info->channel_width_bytes = 4;
+
+ rank = (val >> SKL_DRAM_RANK_SHIFT) & SKL_DRAM_RANK_MASK;
+ if (rank == SKL_DRAM_RANK_SINGLE)
+ info->rank = DRAM_RANK_SINGLE;
+ else
+ info->rank = DRAM_RANK_DUAL;
+}
+
+static int
+skl_get_memdev_info(struct drm_i915_private *dev_priv)
+{
+ uint32_t val = 0;
+ uint32_t mem_speed = 0;
+ struct memdev_info *memdev_info = &dev_priv->memdev_info;
+
+ val = I915_READ(SKL_MC_BIOS_DATA_0_0_0_MCHBAR_PCU);
+ mem_speed = div_u64((uint64_t) (val & SKL_REQ_DATA_MASK) *
+ SKL_MEMORY_FREQ_MULTIPLIER, 1000);
+
+ if (mem_speed == 0)
+ return -EINVAL;
+
+ memdev_info->valid = true;
+ memdev_info->mem_speed_khz = mem_speed;
+ memdev_info->num_channels = 0;
+
+ memdev_info->rank_valid = false;
+ val = I915_READ(SKL_MAD_DIMM_CH0_0_0_0_MCHBAR_MCMAIN);
+
+ if (val != 0xFFFFFFFF) {
+ memdev_info->num_channels++;
+ skl_memdev_info_fill(memdev_info, val);
+ }
+
+ val = I915_READ(SKL_MAD_DIMM_CH1_0_0_0_MCHBAR_MCMAIN);
+
+ if (val != 0xFFFFFFFF) {
+ memdev_info->num_channels++;
+ if (!memdev_info->rank_valid)
+ skl_memdev_info_fill(memdev_info, val);
+ }
+
+ if (memdev_info->num_channels == 0)
+ memdev_info->valid = false;
+ return 0;
+}
+
+static int
+bxt_get_memdev_info(struct drm_i915_private *dev_priv)
+{
+ struct memdev_info *memdev_info = &dev_priv->memdev_info;
+ uint32_t dram_channel;
+ uint32_t mem_speed, val;
+ uint8_t num_channel, dram_type;
+ int i;
+
+ val = I915_READ(BXT_P_CR_MC_BIOS_REQ_0_0_0);
+ mem_speed = div_u64((uint64_t) (val & BXT_REQ_DATA_MASK) *
+ SKL_MEMORY_FREQ_MULTIPLIER, 1000);
+
+ if (mem_speed == 0)
+ return -EINVAL;
+
+ memdev_info->valid = true;
+ memdev_info->mem_speed_khz = mem_speed;
+ dram_type = (val >> BXT_DRAM_TYPE_SHIFT) & BXT_DRAM_TYPE_MASK;
+ dram_channel = (val >> BXT_DRAM_CHANNEL_SHIFT) & BXT_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. In case of single 64 bit
+ * wide DDR3L dimm sets two channel-active bits in
+ * P_CR_MC_BIOS_REQ_0_0_0 register and system with two DDR3L 64bit dimm
+ * will set all four channel-active bits in above register.
+ * In order to get actual number of channels in DDR3L DRAM we need to
+ * device total channel-active bits set by 2.
+ */
+
+ switch (dram_type) {
+ case BXT_DRAM_TYPE_LPDDR3:
+ case BXT_DRAM_TYPE_LPDDR4:
+ memdev_info->channel_width_bytes = 4;
+ memdev_info->num_channels = num_channel;
+ break;
+ case BXT_DRAM_TYPE_DDR3L:
+ memdev_info->channel_width_bytes = 8;
+ memdev_info->num_channels = num_channel / 2;
+ break;
+ default:
+ DRM_DEBUG_KMS("Unknown DRAM type\n");
+ memdev_info->valid = false;
+ return -EINVAL;
+ }
+
+ /*
+ * 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
+ */
+ memdev_info->rank_valid = false;
+ for (i = 0; i < BXT_D_CR_DRP0_DUNIT_MAX; i++) {
+ val = I915_READ(BXT_D_CR_DRP0_DUNIT(i));
+ if (val != 0xFFFFFFFF) {
+ uint8_t rank;
+
+ memdev_info->rank_valid = true;
+ rank = val & BXT_DRAM_RANK_MASK;
+ if (rank == BXT_DRAM_RANK_SINGLE)
+ memdev_info->rank = DRAM_RANK_SINGLE;
+ else if (rank == BXT_DRAM_RANK_DUAL)
+ memdev_info->rank = DRAM_RANK_DUAL;
+ else
+ memdev_info->rank = DRAM_RANK_NONE;
+
+ break;
+ }
+ }
+ return 0;
+}
+
+static void
+intel_get_memdev_info(struct drm_i915_private *dev_priv)
+{
+ struct memdev_info *memdev_info = &dev_priv->memdev_info;
+ int ret;
+
+ memdev_info->valid = false;
+ if (!IS_GEN9(dev_priv))
+ return;
+
+ if (IS_BROXTON(dev_priv))
+ ret = bxt_get_memdev_info(dev_priv);
+ else
+ ret = skl_get_memdev_info(dev_priv);
+ if (ret)
+ return;
+
+ if (memdev_info->valid) {
+ DRM_DEBUG_DRIVER("DRAM speed-%d Khz total-channels-%d channel-width-%d bytes\n",
+ memdev_info->mem_speed_khz,
+ memdev_info->num_channels,
+ memdev_info->channel_width_bytes);
+ if (memdev_info->rank_valid)
+ DRM_DEBUG_DRIVER("DRAM rank-%s\n",
+ (memdev_info->rank == DRAM_RANK_DUAL) ?
+ "dual" : "single");
+ }
+}
+
+
/**
* i915_driver_init_hw - setup state requiring device access
* @dev_priv: device private
@@ -1082,6 +1246,12 @@ 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_priv);
+
return 0;
out_ggtt:
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index a219a35..adbd9aa 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2057,6 +2057,20 @@ struct drm_i915_private {
bool distrust_bios_wm;
} wm;
+ struct memdev_info {
+ bool valid;
+ uint32_t mem_speed_khz;
+ uint8_t channel_width_bytes;
+ uint8_t num_channels;
+ bool rank_valid;
+ enum {
+ DRAM_RANK_NONE = 0,
+ DRAM_RANK_SINGLE,
+ DRAM_RANK_DUAL
+ } 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 acc767a..a9c467c 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7721,6 +7721,44 @@ enum {
#define DC_STATE_DEBUG_MASK_CORES (1<<0)
#define DC_STATE_DEBUG_MASK_MEMORY_UP (1<<1)
+#define _MMIO_MCHBAR_PIPE(x, a, b) _MMIO(MCHBAR_MIRROR_BASE_SNB + _PIPE(x, a, b))
+#define BXT_P_CR_MC_BIOS_REQ_0_0_0 _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x7114)
+#define BXT_REQ_DATA_MASK (0x3F << 0)
+#define BXT_DRAM_TYPE_SHIFT 24
+#define BXT_DRAM_TYPE_MASK 0x7
+#define BXT_DRAM_CHANNEL_SHIFT 12
+#define BXT_DRAM_CHANNEL_MASK 0xF
+
+#define BXT_DRAM_TYPE_LPDDR3 0x1
+#define BXT_DRAM_TYPE_LPDDR4 0x2
+#define BXT_DRAM_TYPE_DDR3L 0x4
+/*
+ * BIOS programs this field of REQ_DATA [5:0] in integer
+ * multiple of 133330 KHz (133.33MHz)
+ */
+#define SKL_MEMORY_FREQ_MULTIPLIER 0x208D2
+#define BXT_D_CR_DRP0_DUNIT8 0x1000
+#define BXT_D_CR_DRP0_DUNIT9 0x1200
+#define BXT_D_CR_DRP0_DUNIT_MAX 4
+#define BXT_D_CR_DRP0_DUNIT(x) _MMIO_MCHBAR_PIPE(x, BXT_D_CR_DRP0_DUNIT8, BXT_D_CR_DRP0_DUNIT9)
+#define BXT_DRAM_RANK_MASK 0x3
+#define BXT_DRAM_RANK_SINGLE 0x1
+#define BXT_DRAM_RANK_DUAL 0x3
+
+#define SKL_MC_BIOS_DATA_0_0_0_MCHBAR_PCU _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5E04)
+#define SKL_REQ_DATA_MASK (0xF << 0)
+#define SKL_MAD_DIMM_CH0_0_0_0_MCHBAR_MCMAIN _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x500C)
+#define SKL_MAD_DIMM_CH1_0_0_0_MCHBAR_MCMAIN _MMIO(MCHBAR_MIRROR_BASE_SNB + 0x5010)
+#define SKL_DRAM_CHANNEL_WIDTH_MASK 0x3
+#define SKL_DRAM_CHANNEL_WIDTH_SHIFT 8
+#define SKL_DRAM_WIDTH_1 0x0
+#define SKL_DRAM_WIDTH_2 0x1
+#define SKL_DRAM_WIDTH_4 0x2
+#define SKL_DRAM_RANK_MASK 0x1
+#define SKL_DRAM_RANK_SHIFT 10
+#define SKL_DRAM_RANK_SINGLE 0x0
+#define SKL_DRAM_RANK_DUAL 0x1
+
/* 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)
--
2.10.1
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