[Intel-gfx] [PATCH 2/3] drm/i915: properly set HSW WM_LP watermarks
Paulo Zanoni
przanoni at gmail.com
Fri May 31 16:45:06 CEST 2013
From: Paulo Zanoni <paulo.r.zanoni at intel.com>
We were previously only setting the WM_PIPE registers, now we are
setting the LP watermark registers. This should allow deeper PC
states, resulting in power savings.
We're only using 1/2 data buffer partitioning for now.
v2: Merge both hsw_compute_pri_wm_* functions (Ville)
v3: - Simplify hsw_compute_wm_results (Ville)
- Rebase due to changes on the previous patch
v4: Unconfuse wm_lp/level (Ville)
Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
---
drivers/gpu/drm/i915/i915_reg.h | 4 +
drivers/gpu/drm/i915/intel_pm.c | 179 ++++++++++++++++++++++++++++++++++++----
2 files changed, 165 insertions(+), 18 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 5a49f8a..8176ba9 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3084,6 +3084,10 @@
#define WM3S_LP_IVB 0x45128
#define WM1S_LP_EN (1<<31)
+#define HSW_WM_LP_VAL(lat, fbc, pri, cur) \
+ (WM3_LP_EN | ((lat) << WM1_LP_LATENCY_SHIFT) | \
+ ((fbc) << WM1_LP_FBC_SHIFT) | ((pri) << WM1_LP_SR_SHIFT) | (cur))
+
/* Memory latency timer register */
#define MLTR_ILK 0x11222
#define MLTR_WM1_SHIFT 0
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index fda7279..1373552 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2129,6 +2129,12 @@ static uint32_t hsw_wm_method2(uint32_t pixel_rate, uint32_t pipe_htotal,
return ret;
}
+static uint32_t hsw_wm_fbc(uint32_t pri_val, uint32_t horiz_pixels,
+ uint8_t bytes_per_pixel)
+{
+ return DIV_ROUND_UP(pri_val * 64, horiz_pixels * bytes_per_pixel) + 2;
+}
+
struct hsw_pipe_wm_parameters {
bool active;
bool sprite_enabled;
@@ -2142,11 +2148,28 @@ struct hsw_pipe_wm_parameters {
uint32_t pixel_rate;
};
+struct hsw_wm_maximums {
+ uint16_t pri;
+ uint16_t spr;
+ uint16_t cur;
+ uint16_t fbc;
+};
+
+struct hsw_lp_wm_result {
+ bool enable;
+ bool fbc_enable;
+ uint32_t pri_val;
+ uint32_t spr_val;
+ uint32_t cur_val;
+ uint32_t fbc_val;
+};
+
struct hsw_wm_values {
uint32_t wm_pipe[3];
uint32_t wm_lp[3];
uint32_t wm_lp_spr[3];
uint32_t wm_linetime[3];
+ bool enable_fbc_wm;
};
enum hsw_data_buf_partitioning {
@@ -2154,17 +2177,31 @@ enum hsw_data_buf_partitioning {
HSW_DATA_BUF_PART_5_6,
};
-/* Only for WM_PIPE. */
-static uint32_t hsw_compute_pri_wm_pipe(struct hsw_pipe_wm_parameters *params,
- uint32_t mem_value)
+/* For both WM_PIPE and WM_LP. */
+static uint32_t hsw_compute_pri_wm(struct hsw_pipe_wm_parameters *params,
+ uint32_t mem_value,
+ bool is_lp)
{
+ uint32_t method1, method2;
+
/* TODO: for now, assume the primary plane is always enabled. */
if (!params->active)
return 0;
- return hsw_wm_method1(params->pixel_rate,
- params->pri_bytes_per_pixel,
- mem_value);
+ method1 = hsw_wm_method1(params->pixel_rate,
+ params->pri_bytes_per_pixel,
+ mem_value);
+
+ if (!is_lp)
+ return method1;
+
+ method2 = hsw_wm_method2(params->pixel_rate,
+ params->pipe_htotal,
+ params->pri_horiz_pixels,
+ params->pri_bytes_per_pixel,
+ mem_value);
+
+ return min(method1, method2);
}
/* For both WM_PIPE and WM_LP. */
@@ -2201,13 +2238,60 @@ static uint32_t hsw_compute_cur_wm(struct hsw_pipe_wm_parameters *params,
mem_value);
}
+/* Only for WM_LP. */
+static uint32_t hsw_compute_fbc_wm(struct hsw_pipe_wm_parameters *params,
+ uint32_t pri_val,
+ uint32_t mem_value)
+{
+ if (!params->active)
+ return 0;
+
+ return hsw_wm_fbc(pri_val,
+ params->pri_horiz_pixels,
+ params->pri_bytes_per_pixel);
+}
+
+static bool hsw_compute_lp_wm(uint32_t mem_value, struct hsw_wm_maximums *max,
+ struct hsw_pipe_wm_parameters *params,
+ struct hsw_lp_wm_result *result)
+{
+ enum pipe pipe;
+ uint32_t pri_val[3], spr_val[3], cur_val[3], fbc_val[3];
+
+ for (pipe = PIPE_A; pipe <= PIPE_C; pipe++) {
+ struct hsw_pipe_wm_parameters *p = ¶ms[pipe];
+
+ pri_val[pipe] = hsw_compute_pri_wm(p, mem_value, true);
+ spr_val[pipe] = hsw_compute_spr_wm(p, mem_value);
+ cur_val[pipe] = hsw_compute_cur_wm(p, mem_value);
+ fbc_val[pipe] = hsw_compute_fbc_wm(p, pri_val[pipe], mem_value);
+ }
+
+ result->pri_val = max3(pri_val[0], pri_val[1], pri_val[2]);
+ result->spr_val = max3(spr_val[0], spr_val[1], spr_val[2]);
+ result->cur_val = max3(cur_val[0], cur_val[1], cur_val[2]);
+ result->fbc_val = max3(fbc_val[0], fbc_val[1], fbc_val[2]);
+
+ if (result->fbc_val > max->fbc) {
+ result->fbc_enable = false;
+ result->fbc_val = 0;
+ } else {
+ result->fbc_enable = true;
+ }
+
+ result->enable = result->pri_val <= max->pri &&
+ result->spr_val <= max->spr &&
+ result->cur_val <= max->cur;
+ return result->enable;
+}
+
static uint32_t hsw_compute_wm_pipe(struct drm_i915_private *dev_priv,
uint32_t mem_value, enum pipe pipe,
struct hsw_pipe_wm_parameters *params)
{
uint32_t pri_val, cur_val, spr_val;
- pri_val = hsw_compute_pri_wm_pipe(params, mem_value);
+ pri_val = hsw_compute_pri_wm(params, mem_value, false);
spr_val = hsw_compute_spr_wm(params, mem_value);
cur_val = hsw_compute_cur_wm(params, mem_value);
@@ -2250,13 +2334,15 @@ hsw_compute_linetime_wm(struct drm_device *dev, struct drm_crtc *crtc)
static void hsw_compute_wm_parameters(struct drm_device *dev,
struct hsw_pipe_wm_parameters *params,
- uint32_t *wm)
+ uint32_t *wm,
+ struct hsw_wm_maximums *lp_max_1_2)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_crtc *crtc;
struct drm_plane *plane;
uint64_t sskpd = I915_READ64(MCH_SSKPD);
enum pipe pipe;
+ int pipes_active = 0, sprites_enabled = 0;
if ((sskpd >> 56) & 0xFF)
wm[0] = (sskpd >> 56) & 0xFF;
@@ -2278,6 +2364,8 @@ static void hsw_compute_wm_parameters(struct drm_device *dev,
if (!p->active)
continue;
+ pipes_active++;
+
p->pipe_htotal = intel_crtc->config.adjusted_mode.htotal;
p->pixel_rate = hsw_wm_get_pixel_rate(dev, crtc);
p->pri_bytes_per_pixel = crtc->fb->bits_per_pixel / 8;
@@ -2297,25 +2385,66 @@ static void hsw_compute_wm_parameters(struct drm_device *dev,
p->sprite_enabled = intel_plane->wm.enable;
p->spr_bytes_per_pixel = intel_plane->wm.bytes_per_pixel;
p->spr_horiz_pixels = intel_plane->wm.horiz_pixels;
+
+ if (p->sprite_enabled)
+ sprites_enabled++;
+ }
+
+ if (pipes_active > 1) {
+ lp_max_1_2->pri = sprites_enabled ? 128 : 256;
+ lp_max_1_2->spr = 128;
+ lp_max_1_2->cur = 64;
+ } else {
+ lp_max_1_2->pri = sprites_enabled ? 384 : 768;
+ lp_max_1_2->spr = 384;
+ lp_max_1_2->cur = 255;
}
+ lp_max_1_2->fbc = 15;
}
static void hsw_compute_wm_results(struct drm_device *dev,
struct hsw_pipe_wm_parameters *params,
uint32_t *wm,
+ struct hsw_wm_maximums *lp_maximums,
struct hsw_wm_values *results)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_crtc *crtc;
+ struct hsw_lp_wm_result lp_results[4] = {};
enum pipe pipe;
+ int level, max_level, wm_lp;
+
+ for (level = 1; level <= 4; level++)
+ if (!hsw_compute_lp_wm(wm[level], lp_maximums, params,
+ &lp_results[level - 1]))
+ break;
+ max_level = level - 1;
+
+ /* The spec says it is preferred to disable FBC WMs instead of disabling
+ * a WM level. */
+ results->enable_fbc_wm = true;
+ for (level = 1; level <= max_level; level++) {
+ if (!lp_results[level - 1].fbc_enable) {
+ results->enable_fbc_wm = false;
+ break;
+ }
+ }
+
+ memset(results, 0, sizeof(*results));
+ for (wm_lp = 1; wm_lp <= 3; wm_lp++) {
+ const struct hsw_lp_wm_result *r;
- /* No support for LP WMs yet. */
- results->wm_lp[2] = 0;
- results->wm_lp[1] = 0;
- results->wm_lp[0] = 0;
- results->wm_lp_spr[2] = 0;
- results->wm_lp_spr[1] = 0;
- results->wm_lp_spr[0] = 0;
+ level = (max_level == 4 && wm_lp > 1) ? wm_lp + 1 : wm_lp;
+ if (level > max_level)
+ break;
+
+ r = &lp_results[level - 1];
+ results->wm_lp[wm_lp - 1] = HSW_WM_LP_VAL(level * 2,
+ r->fbc_val,
+ r->pri_val,
+ r->cur_val);
+ results->wm_lp_spr[wm_lp - 1] = r->spr_val;
+ }
for_each_pipe(pipe)
results->wm_pipe[pipe] = hsw_compute_wm_pipe(dev_priv, wm[0],
@@ -2339,6 +2468,7 @@ static void hsw_write_wm_values(struct drm_i915_private *dev_priv,
struct hsw_wm_values previous;
uint32_t val;
enum hsw_data_buf_partitioning prev_partitioning;
+ bool prev_enable_fbc_wm;
previous.wm_pipe[0] = I915_READ(WM0_PIPEA_ILK);
previous.wm_pipe[1] = I915_READ(WM0_PIPEB_ILK);
@@ -2356,6 +2486,8 @@ static void hsw_write_wm_values(struct drm_i915_private *dev_priv,
prev_partitioning = (I915_READ(WM_MISC) & WM_MISC_DATA_PARTITION_5_6) ?
HSW_DATA_BUF_PART_5_6 : HSW_DATA_BUF_PART_1_2;
+ prev_enable_fbc_wm = !(I915_READ(DISP_ARB_CTL) & DISP_FBC_WM_DIS);
+
if (memcmp(results->wm_pipe, previous.wm_pipe,
sizeof(results->wm_pipe)) == 0 &&
memcmp(results->wm_lp, previous.wm_lp,
@@ -2364,7 +2496,8 @@ static void hsw_write_wm_values(struct drm_i915_private *dev_priv,
sizeof(results->wm_lp_spr)) == 0 &&
memcmp(results->wm_linetime, previous.wm_linetime,
sizeof(results->wm_linetime)) == 0 &&
- partitioning == prev_partitioning)
+ partitioning == prev_partitioning &&
+ results->enable_fbc_wm == prev_enable_fbc_wm)
return;
if (previous.wm_lp[2] != 0)
@@ -2397,6 +2530,15 @@ static void hsw_write_wm_values(struct drm_i915_private *dev_priv,
I915_WRITE(WM_MISC, val);
}
+ if (prev_enable_fbc_wm != results->enable_fbc_wm) {
+ val = I915_READ(DISP_ARB_CTL);
+ if (results->enable_fbc_wm)
+ val &= ~DISP_FBC_WM_DIS;
+ else
+ val |= DISP_FBC_WM_DIS;
+ I915_WRITE(DISP_ARB_CTL, val);
+ }
+
if (previous.wm_lp_spr[0] != results->wm_lp_spr[0])
I915_WRITE(WM1S_LP_ILK, results->wm_lp_spr[0]);
if (previous.wm_lp_spr[1] != results->wm_lp_spr[1])
@@ -2415,12 +2557,13 @@ static void hsw_write_wm_values(struct drm_i915_private *dev_priv,
static void haswell_update_wm(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
+ struct hsw_wm_maximums lp_max_1_2;
struct hsw_pipe_wm_parameters params[3];
struct hsw_wm_values results;
uint32_t wm[5];
- hsw_compute_wm_parameters(dev, params, wm);
- hsw_compute_wm_results(dev, params, wm, &results);
+ hsw_compute_wm_parameters(dev, params, wm, &lp_max_1_2);
+ hsw_compute_wm_results(dev, params, wm, &lp_max_1_2, &results);
hsw_write_wm_values(dev_priv, &results, HSW_DATA_BUF_PART_1_2);
}
--
1.8.1.2
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