[Intel-gfx] [PATCH 2/5] drm/i915/skl+: Decode memory bandwidth and parameters
Mahesh Kumar
mahesh1.kumar at intel.com
Thu Jul 26 14:14:07 UTC 2018
This patch adds support to decode system memory bandwidth and other
parameters for skylake and Gen9+ platforms, which will be used for
arbitrated display memory bandwidth calculation in GEN9 based
platforms and WM latency level-0 Work-around calculation on GEN9+.
Changes Since V1:
- s/memdev_info/dram_info
- create a struct to hold channel info
Signed-off-by: Mahesh Kumar <mahesh1.kumar at intel.com>
---
drivers/gpu/drm/i915/i915_drv.c | 131 ++++++++++++++++++++++++++++++++++++++--
drivers/gpu/drm/i915/i915_drv.h | 7 +++
drivers/gpu/drm/i915/i915_reg.h | 21 +++++++
3 files changed, 155 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 16629601c9f4..ddf6bf9b500a 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -1070,6 +1070,118 @@ static void intel_sanitize_options(struct drm_i915_private *dev_priv)
intel_gvt_sanitize_options(dev_priv);
}
+static int
+skl_dram_get_channel_info(struct dram_channel_info *ch, u32 val)
+{
+ u8 l_rank, s_rank;
+ u8 l_size, s_size;
+ u8 l_width, s_width;
+ enum dram_rank rank;
+
+ if (!val)
+ return -1;
+
+ l_size = (val >> SKL_DRAM_SIZE_L_SHIFT) & SKL_DRAM_SIZE_MASK;
+ s_size = (val >> SKL_DRAM_SIZE_S_SHIFT) & SKL_DRAM_SIZE_MASK;
+ l_width = (val >> SKL_DRAM_WIDTH_L_SHIFT) & SKL_DRAM_WIDTH_MASK;
+ s_width = (val >> SKL_DRAM_WIDTH_S_SHIFT) & SKL_DRAM_WIDTH_MASK;
+ l_rank = (val >> SKL_DRAM_RANK_L_SHIFT) & SKL_DRAM_RANK_MASK;
+ s_rank = (val >> SKL_DRAM_RANK_S_SHIFT) & SKL_DRAM_RANK_MASK;
+
+ if (l_size == 0 && s_size == 0)
+ return -1;
+
+ DRM_DEBUG_KMS("(size:width:rank) L(%dGB:X%d:%s) S(%dGB:X%d:%s)\n",
+ l_size, (1 << l_width) * 8, l_rank ? "dual" : "single",
+ s_size, (1 << s_width) * 8, s_rank ? "dual" : "single");
+
+ if (l_rank == SKL_DRAM_RANK_DUAL || s_rank == SKL_DRAM_RANK_DUAL)
+ rank = I915_DRAM_RANK_DUAL;
+ else if ((l_size && l_rank == SKL_DRAM_RANK_SINGLE) &&
+ (s_size && s_rank == SKL_DRAM_RANK_SINGLE))
+ rank = I915_DRAM_RANK_DUAL;
+ else
+ rank = I915_DRAM_RANK_SINGLE;
+
+ ch->l_info.size = l_size;
+ ch->s_info.size = s_size;
+ ch->l_info.width = l_width;
+ ch->s_info.width = s_width;
+ ch->l_info.rank = l_rank;
+ ch->s_info.rank = s_rank;
+ ch->rank = rank;
+
+ return 0;
+}
+
+static int
+skl_dram_get_channels_info(struct drm_i915_private *dev_priv)
+{
+ struct dram_info *dram_info = &dev_priv->dram_info;
+ struct dram_channel_info ch0, ch1;
+ u32 val;
+ int ret;
+
+ val = I915_READ(SKL_MAD_DIMM_CH0_0_0_0_MCHBAR_MCMAIN);
+ ret = skl_dram_get_channel_info(&ch0, val);
+ if (ret == 0)
+ dram_info->num_channels++;
+
+ val = I915_READ(SKL_MAD_DIMM_CH1_0_0_0_MCHBAR_MCMAIN);
+ ret = skl_dram_get_channel_info(&ch1, val);
+ if (ret == 0)
+ dram_info->num_channels++;
+
+ if (dram_info->num_channels == 0) {
+ DRM_INFO("Number of memory channels is zero\n");
+ return -EINVAL;
+ }
+
+ /*
+ * If any of the channel is single rank channel, worst case output
+ * will be same as if single rank memory, so consider single rank
+ * memory.
+ */
+ if (ch0.rank == I915_DRAM_RANK_SINGLE ||
+ ch1.rank == I915_DRAM_RANK_SINGLE)
+ dram_info->rank = I915_DRAM_RANK_SINGLE;
+ else
+ dram_info->rank = max(ch0.rank, ch1.rank);
+
+ if (dram_info->rank == I915_DRAM_RANK_INVALID) {
+ DRM_INFO("couldn't get memory rank information\n");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int
+skl_get_dram_info(struct drm_i915_private *dev_priv)
+{
+ struct dram_info *dram_info = &dev_priv->dram_info;
+ u32 mem_freq_khz, val;
+ int ret;
+
+ ret = skl_dram_get_channels_info(dev_priv);
+ if (ret)
+ return ret;
+
+ val = I915_READ(SKL_MC_BIOS_DATA_0_0_0_MCHBAR_PCU);
+ mem_freq_khz = DIV_ROUND_UP((val & SKL_REQ_DATA_MASK) *
+ SKL_MEMORY_FREQ_MULTIPLIER_HZ, 1000);
+
+ dram_info->bandwidth_kbps = dram_info->num_channels *
+ mem_freq_khz * 8;
+
+ if (dram_info->bandwidth_kbps == 0) {
+ DRM_INFO("Couldn't get system memory bandwidth\n");
+ return -EINVAL;
+ }
+
+ dram_info->valid = true;
+ return 0;
+}
+
static int
bxt_get_dram_info(struct drm_i915_private *dev_priv)
{
@@ -1159,6 +1271,7 @@ static void
intel_get_dram_info(struct drm_i915_private *dev_priv)
{
struct dram_info *dram_info = &dev_priv->dram_info;
+ char bandwidth_str[32];
int ret;
dram_info->valid = false;
@@ -1166,15 +1279,25 @@ intel_get_dram_info(struct drm_i915_private *dev_priv)
dram_info->bandwidth_kbps = 0;
dram_info->num_channels = 0;
- if (!IS_BROXTON(dev_priv))
+ if (INTEL_GEN(dev_priv) < 9)
return;
- ret = bxt_get_dram_info(dev_priv);
+ /* Need to calculate bandwidth only for Gen9 */
+ if (IS_BROXTON(dev_priv))
+ ret = bxt_get_dram_info(dev_priv);
+ else if (INTEL_GEN(dev_priv) == 9)
+ ret = skl_get_dram_info(dev_priv);
+ else
+ ret = skl_dram_get_channels_info(dev_priv);
if (ret)
return;
- DRM_DEBUG_KMS("DRAM bandwidth:%d KBps, total-channels: %u\n",
- dram_info->bandwidth_kbps, dram_info->num_channels);
+ if (dram_info->bandwidth_kbps)
+ sprintf(bandwidth_str, "%d KBps", dram_info->bandwidth_kbps);
+ else
+ sprintf(bandwidth_str, "unknown");
+ DRM_DEBUG_KMS("DRAM bandwidth:%s, total-channels: %u\n",
+ bandwidth_str, dram_info->num_channels);
DRM_DEBUG_KMS("DRAM rank: %s rank\n",
(dram_info->rank == I915_DRAM_RANK_DUAL) ?
"dual" : "single");
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 46f942fa7d60..2d12fc152b49 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2128,6 +2128,13 @@ struct drm_i915_private {
*/
};
+struct dram_channel_info {
+ struct info {
+ u8 size, width, rank;
+ } l_info, s_info;
+ enum dram_rank rank;
+};
+
static inline struct drm_i915_private *to_i915(const struct drm_device *dev)
{
return container_of(dev, struct drm_i915_private, drm);
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 66900d027570..e4d61167fb64 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -9664,6 +9664,27 @@ enum skl_power_gate {
#define BXT_DRAM_SIZE_12GB 0x3
#define BXT_DRAM_SIZE_16GB 0x4
+#define SKL_MEMORY_FREQ_MULTIPLIER_HZ 266666666
+#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_SIZE_MASK 0x3F
+#define SKL_DRAM_SIZE_L_SHIFT 0
+#define SKL_DRAM_SIZE_S_SHIFT 16
+#define SKL_DRAM_WIDTH_MASK 0x3
+#define SKL_DRAM_WIDTH_L_SHIFT 8
+#define SKL_DRAM_WIDTH_S_SHIFT 24
+#define SKL_DRAM_WIDTH_X8 0x0
+#define SKL_DRAM_WIDTH_X16 0x1
+#define SKL_DRAM_WIDTH_X32 0x2
+#define SKL_DRAM_RANK_MASK 0x1
+#define SKL_DRAM_RANK_L_SHIFT 10
+#define SKL_DRAM_RANK_S_SHIFT 26
+#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)
--
2.16.2
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