diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_pm.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_pm.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 2c88c2f..496a911 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -2852,6 +2852,7 @@ bool ilk_disable_lp_wm(struct drm_device *dev) #define SKL_DDB_SIZE 896 /* in blocks */ #define BXT_DDB_SIZE 512 +#define SKL_SAGV_BLOCK_TIME 30 /* µs */ /* * Return the index of a plane in the SKL DDB and wm result arrays. Primary @@ -2875,6 +2876,153 @@ skl_wm_plane_id(const struct intel_plane *plane) } } +/* + * SAGV dynamically adjusts the system agent voltage and clock frequencies + * depending on power and performance requirements. The display engine access + * to system memory is blocked during the adjustment time. Because of the + * blocking time, having this enabled can cause full system hangs and/or pipe + * underruns if we don't meet all of the following requirements: + * + * - <= 1 pipe enabled + * - All planes can enable watermarks for latencies >= SAGV engine block time + * - We're not using an interlaced display configuration + */ +int +skl_enable_sagv(struct drm_i915_private *dev_priv) +{ + int ret; + + if (dev_priv->skl_sagv_status == I915_SKL_SAGV_NOT_CONTROLLED || + dev_priv->skl_sagv_status == I915_SKL_SAGV_ENABLED) + return 0; + + DRM_DEBUG_KMS("Enabling the SAGV\n"); + mutex_lock(&dev_priv->rps.hw_lock); + + ret = sandybridge_pcode_write(dev_priv, GEN9_PCODE_SAGV_CONTROL, + GEN9_SAGV_ENABLE); + + /* We don't need to wait for the SAGV when enabling */ + mutex_unlock(&dev_priv->rps.hw_lock); + + /* + * Some skl systems, pre-release machines in particular, + * don't actually have an SAGV. + */ + if (ret == -ENXIO) { + DRM_DEBUG_DRIVER("No SAGV found on system, ignoring\n"); + dev_priv->skl_sagv_status = I915_SKL_SAGV_NOT_CONTROLLED; + return 0; + } else if (ret < 0) { + DRM_ERROR("Failed to enable the SAGV\n"); + return ret; + } + + dev_priv->skl_sagv_status = I915_SKL_SAGV_ENABLED; + return 0; +} + +static int +skl_do_sagv_disable(struct drm_i915_private *dev_priv) +{ + int ret; + uint32_t temp = GEN9_SAGV_DISABLE; + + ret = sandybridge_pcode_read(dev_priv, GEN9_PCODE_SAGV_CONTROL, + &temp); + if (ret) + return ret; + else + return temp & GEN9_SAGV_IS_DISABLED; +} + +int +skl_disable_sagv(struct drm_i915_private *dev_priv) +{ + int ret, result; + + if (dev_priv->skl_sagv_status == I915_SKL_SAGV_NOT_CONTROLLED || + dev_priv->skl_sagv_status == I915_SKL_SAGV_DISABLED) + return 0; + + DRM_DEBUG_KMS("Disabling the SAGV\n"); + mutex_lock(&dev_priv->rps.hw_lock); + + /* bspec says to keep retrying for at least 1 ms */ + ret = wait_for(result = skl_do_sagv_disable(dev_priv), 1); + mutex_unlock(&dev_priv->rps.hw_lock); + + if (ret == -ETIMEDOUT) { + DRM_ERROR("Request to disable SAGV timed out\n"); + return -ETIMEDOUT; + } + + /* + * Some skl systems, pre-release machines in particular, + * don't actually have an SAGV. + */ + if (result == -ENXIO) { + DRM_DEBUG_DRIVER("No SAGV found on system, ignoring\n"); + dev_priv->skl_sagv_status = I915_SKL_SAGV_NOT_CONTROLLED; + return 0; + } else if (result < 0) { + DRM_ERROR("Failed to disable the SAGV\n"); + return result; + } + + dev_priv->skl_sagv_status = I915_SKL_SAGV_DISABLED; + return 0; +} + +bool skl_can_enable_sagv(struct drm_atomic_state *state) +{ + struct drm_device *dev = state->dev; + struct drm_i915_private *dev_priv = to_i915(dev); + struct intel_atomic_state *intel_state = to_intel_atomic_state(state); + struct drm_crtc *crtc; + enum pipe pipe; + int level, plane; + + /* + * SKL workaround: bspec recommends we disable the SAGV when we have + * more then one pipe enabled + * + * If there are no active CRTCs, no additional checks need be performed + */ + if (hweight32(intel_state->active_crtcs) == 0) + return true; + else if (hweight32(intel_state->active_crtcs) > 1) + return false; + + /* Since we're now guaranteed to only have one active CRTC... */ + pipe = ffs(intel_state->active_crtcs) - 1; + crtc = dev_priv->pipe_to_crtc_mapping[pipe]; + + if (crtc->state->mode.flags & DRM_MODE_FLAG_INTERLACE) + return false; + + for_each_plane(dev_priv, pipe, plane) { + /* Skip this plane if it's not enabled */ + if (intel_state->wm_results.plane[pipe][plane][0] == 0) + continue; + + /* Find the highest enabled wm level for this plane */ + for (level = ilk_wm_max_level(dev); + intel_state->wm_results.plane[pipe][plane][level] == 0; --level) + { } + + /* + * If any of the planes on this pipe don't enable wm levels + * that incur memory latencies higher then 30µs we can't enable + * the SAGV + */ + if (dev_priv->wm.skl_latency[level] < SKL_SAGV_BLOCK_TIME) + return false; + } + + return true; +} + static void skl_ddb_get_pipe_allocation_limits(struct drm_device *dev, const struct intel_crtc_state *cstate, |
