diff options
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_drrs.c')
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_drrs.c | 437 |
1 files changed, 437 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_drrs.c b/drivers/gpu/drm/i915/display/intel_drrs.c new file mode 100644 index 000000000000..c1439fcb5a95 --- /dev/null +++ b/drivers/gpu/drm/i915/display/intel_drrs.c @@ -0,0 +1,437 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2021 Intel Corporation + */ + +#include "i915_drv.h" +#include "intel_atomic.h" +#include "intel_de.h" +#include "intel_display_types.h" +#include "intel_drrs.h" +#include "intel_panel.h" + +/** + * DOC: Display Refresh Rate Switching (DRRS) + * + * Display Refresh Rate Switching (DRRS) is a power conservation feature + * which enables swtching between low and high refresh rates, + * dynamically, based on the usage scenario. This feature is applicable + * for internal panels. + * + * Indication that the panel supports DRRS is given by the panel EDID, which + * would list multiple refresh rates for one resolution. + * + * DRRS is of 2 types - static and seamless. + * Static DRRS involves changing refresh rate (RR) by doing a full modeset + * (may appear as a blink on screen) and is used in dock-undock scenario. + * Seamless DRRS involves changing RR without any visual effect to the user + * and can be used during normal system usage. This is done by programming + * certain registers. + * + * Support for static/seamless DRRS may be indicated in the VBT based on + * inputs from the panel spec. + * + * DRRS saves power by switching to low RR based on usage scenarios. + * + * The implementation is based on frontbuffer tracking implementation. When + * there is a disturbance on the screen triggered by user activity or a periodic + * system activity, DRRS is disabled (RR is changed to high RR). When there is + * no movement on screen, after a timeout of 1 second, a switch to low RR is + * made. + * + * For integration with frontbuffer tracking code, intel_drrs_invalidate() + * and intel_drrs_flush() are called. + * + * DRRS can be further extended to support other internal panels and also + * the scenario of video playback wherein RR is set based on the rate + * requested by userspace. + */ + +void +intel_drrs_compute_config(struct intel_dp *intel_dp, + struct intel_crtc_state *pipe_config, + int output_bpp, bool constant_n) +{ + struct intel_connector *intel_connector = intel_dp->attached_connector; + struct drm_i915_private *dev_priv = dp_to_i915(intel_dp); + int pixel_clock; + + if (pipe_config->vrr.enable) + return; + + /* + * DRRS and PSR can't be enable together, so giving preference to PSR + * as it allows more power-savings by complete shutting down display, + * so to guarantee this, intel_drrs_compute_config() must be called + * after intel_psr_compute_config(). + */ + if (pipe_config->has_psr) + return; + + if (!intel_connector->panel.downclock_mode || + dev_priv->drrs.type != SEAMLESS_DRRS_SUPPORT) + return; + + pipe_config->has_drrs = true; + + pixel_clock = intel_connector->panel.downclock_mode->clock; + if (pipe_config->splitter.enable) + pixel_clock /= pipe_config->splitter.link_count; + + intel_link_compute_m_n(output_bpp, pipe_config->lane_count, pixel_clock, + pipe_config->port_clock, &pipe_config->dp_m2_n2, + constant_n, pipe_config->fec_enable); + + /* FIXME: abstract this better */ + if (pipe_config->splitter.enable) + pipe_config->dp_m2_n2.gmch_m *= pipe_config->splitter.link_count; +} + +static void intel_drrs_set_state(struct drm_i915_private *dev_priv, + const struct intel_crtc_state *crtc_state, + enum drrs_refresh_rate_type refresh_type) +{ + struct intel_dp *intel_dp = dev_priv->drrs.dp; + struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc); + struct drm_display_mode *mode; + + if (!intel_dp) { + drm_dbg_kms(&dev_priv->drm, "DRRS not supported.\n"); + return; + } + + if (!crtc) { + drm_dbg_kms(&dev_priv->drm, + "DRRS: intel_crtc not initialized\n"); + return; + } + + if (dev_priv->drrs.type < SEAMLESS_DRRS_SUPPORT) { + drm_dbg_kms(&dev_priv->drm, "Only Seamless DRRS supported.\n"); + return; + } + + if (refresh_type == dev_priv->drrs.refresh_rate_type) + return; + + if (!crtc_state->hw.active) { + drm_dbg_kms(&dev_priv->drm, + "eDP encoder disabled. CRTC not Active\n"); + return; + } + + if (DISPLAY_VER(dev_priv) >= 8 && !IS_CHERRYVIEW(dev_priv)) { + switch (refresh_type) { + case DRRS_HIGH_RR: + intel_dp_set_m_n(crtc_state, M1_N1); + break; + case DRRS_LOW_RR: + intel_dp_set_m_n(crtc_state, M2_N2); + break; + case DRRS_MAX_RR: + default: + drm_err(&dev_priv->drm, + "Unsupported refreshrate type\n"); + } + } else if (DISPLAY_VER(dev_priv) > 6) { + i915_reg_t reg = PIPECONF(crtc_state->cpu_transcoder); + u32 val; + + val = intel_de_read(dev_priv, reg); + if (refresh_type == DRRS_LOW_RR) { + if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) + val |= PIPECONF_EDP_RR_MODE_SWITCH_VLV; + else + val |= PIPECONF_EDP_RR_MODE_SWITCH; + } else { + if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) + val &= ~PIPECONF_EDP_RR_MODE_SWITCH_VLV; + else + val &= ~PIPECONF_EDP_RR_MODE_SWITCH; + } + intel_de_write(dev_priv, reg, val); + } + + dev_priv->drrs.refresh_rate_type = refresh_type; + + if (refresh_type == DRRS_LOW_RR) + mode = intel_dp->attached_connector->panel.downclock_mode; + else + mode = intel_dp->attached_connector->panel.fixed_mode; + drm_dbg_kms(&dev_priv->drm, "eDP Refresh Rate set to : %dHz\n", + drm_mode_vrefresh(mode)); +} + +static void +intel_drrs_enable_locked(struct intel_dp *intel_dp) +{ + struct drm_i915_private *dev_priv = dp_to_i915(intel_dp); + + dev_priv->drrs.busy_frontbuffer_bits = 0; + dev_priv->drrs.dp = intel_dp; +} + +/** + * intel_drrs_enable - init drrs struct if supported + * @intel_dp: DP struct + * @crtc_state: A pointer to the active crtc state. + * + * Initializes frontbuffer_bits and drrs.dp + */ +void intel_drrs_enable(struct intel_dp *intel_dp, + const struct intel_crtc_state *crtc_state) +{ + struct drm_i915_private *dev_priv = dp_to_i915(intel_dp); + + if (!crtc_state->has_drrs) + return; + + drm_dbg_kms(&dev_priv->drm, "Enabling DRRS\n"); + + mutex_lock(&dev_priv->drrs.mutex); + + if (dev_priv->drrs.dp) { + drm_warn(&dev_priv->drm, "DRRS already enabled\n"); + goto unlock; + } + + intel_drrs_enable_locked(intel_dp); + +unlock: + mutex_unlock(&dev_priv->drrs.mutex); +} + +static void +intel_drrs_disable_locked(struct intel_dp *intel_dp, + const struct intel_crtc_state *crtc_state) +{ + struct drm_i915_private *dev_priv = dp_to_i915(intel_dp); + + intel_drrs_set_state(dev_priv, crtc_state, DRRS_HIGH_RR); + dev_priv->drrs.dp = NULL; +} + +/** + * intel_drrs_disable - Disable DRRS + * @intel_dp: DP struct + * @old_crtc_state: Pointer to old crtc_state. + * + */ +void intel_drrs_disable(struct intel_dp *intel_dp, + const struct intel_crtc_state *old_crtc_state) +{ + struct drm_i915_private *dev_priv = dp_to_i915(intel_dp); + + if (!old_crtc_state->has_drrs) + return; + + mutex_lock(&dev_priv->drrs.mutex); + if (!dev_priv->drrs.dp) { + mutex_unlock(&dev_priv->drrs.mutex); + return; + } + + intel_drrs_disable_locked(intel_dp, old_crtc_state); + mutex_unlock(&dev_priv->drrs.mutex); + + cancel_delayed_work_sync(&dev_priv->drrs.work); +} + +/** + * intel_drrs_update - Update DRRS state + * @intel_dp: Intel DP + * @crtc_state: new CRTC state + * + * This function will update DRRS states, disabling or enabling DRRS when + * executing fastsets. For full modeset, intel_drrs_disable() and + * intel_drrs_enable() should be called instead. + */ +void +intel_drrs_update(struct intel_dp *intel_dp, + const struct intel_crtc_state *crtc_state) +{ + struct drm_i915_private *dev_priv = dp_to_i915(intel_dp); + + if (dev_priv->drrs.type != SEAMLESS_DRRS_SUPPORT) + return; + + mutex_lock(&dev_priv->drrs.mutex); + + /* New state matches current one? */ + if (crtc_state->has_drrs == !!dev_priv->drrs.dp) + goto unlock; + + if (crtc_state->has_drrs) + intel_drrs_enable_locked(intel_dp); + else + intel_drrs_disable_locked(intel_dp, crtc_state); + +unlock: + mutex_unlock(&dev_priv->drrs.mutex); +} + +static void intel_drrs_downclock_work(struct work_struct *work) +{ + struct drm_i915_private *dev_priv = + container_of(work, typeof(*dev_priv), drrs.work.work); + struct intel_dp *intel_dp; + struct drm_crtc *crtc; + + mutex_lock(&dev_priv->drrs.mutex); + + intel_dp = dev_priv->drrs.dp; + + if (!intel_dp) + goto unlock; + + /* + * The delayed work can race with an invalidate hence we need to + * recheck. + */ + + if (dev_priv->drrs.busy_frontbuffer_bits) + goto unlock; + + crtc = dp_to_dig_port(intel_dp)->base.base.crtc; + intel_drrs_set_state(dev_priv, to_intel_crtc(crtc)->config, DRRS_LOW_RR); + +unlock: + mutex_unlock(&dev_priv->drrs.mutex); +} + +static void intel_drrs_frontbuffer_update(struct drm_i915_private *dev_priv, + unsigned int frontbuffer_bits, + bool invalidate) +{ + struct intel_dp *intel_dp; + struct drm_crtc *crtc; + enum pipe pipe; + + if (dev_priv->drrs.type == DRRS_NOT_SUPPORTED) + return; + + cancel_delayed_work(&dev_priv->drrs.work); + + mutex_lock(&dev_priv->drrs.mutex); + + intel_dp = dev_priv->drrs.dp; + if (!intel_dp) { + mutex_unlock(&dev_priv->drrs.mutex); + return; + } + + crtc = dp_to_dig_port(intel_dp)->base.base.crtc; + pipe = to_intel_crtc(crtc)->pipe; + + frontbuffer_bits &= INTEL_FRONTBUFFER_ALL_MASK(pipe); + if (invalidate) + dev_priv->drrs.busy_frontbuffer_bits |= frontbuffer_bits; + else + dev_priv->drrs.busy_frontbuffer_bits &= ~frontbuffer_bits; + + /* flush/invalidate means busy screen hence upclock */ + if (frontbuffer_bits) + intel_drrs_set_state(dev_priv, to_intel_crtc(crtc)->config, + DRRS_HIGH_RR); + + /* + * flush also means no more activity hence schedule downclock, if all + * other fbs are quiescent too + */ + if (!invalidate && !dev_priv->drrs.busy_frontbuffer_bits) + schedule_delayed_work(&dev_priv->drrs.work, + msecs_to_jiffies(1000)); + mutex_unlock(&dev_priv->drrs.mutex); +} + +/** + * intel_drrs_invalidate - Disable Idleness DRRS + * @dev_priv: i915 device + * @frontbuffer_bits: frontbuffer plane tracking bits + * + * This function gets called everytime rendering on the given planes start. + * Hence DRRS needs to be Upclocked, i.e. (LOW_RR -> HIGH_RR). + * + * Dirty frontbuffers relevant to DRRS are tracked in busy_frontbuffer_bits. + */ +void intel_drrs_invalidate(struct drm_i915_private *dev_priv, + unsigned int frontbuffer_bits) +{ + intel_drrs_frontbuffer_update(dev_priv, frontbuffer_bits, true); +} + +/** + * intel_drrs_flush - Restart Idleness DRRS + * @dev_priv: i915 device + * @frontbuffer_bits: frontbuffer plane tracking bits + * + * This function gets called every time rendering on the given planes has + * completed or flip on a crtc is completed. So DRRS should be upclocked + * (LOW_RR -> HIGH_RR). And also Idleness detection should be started again, + * if no other planes are dirty. + * + * Dirty frontbuffers relevant to DRRS are tracked in busy_frontbuffer_bits. + */ +void intel_drrs_flush(struct drm_i915_private *dev_priv, + unsigned int frontbuffer_bits) +{ + intel_drrs_frontbuffer_update(dev_priv, frontbuffer_bits, false); +} + +void intel_drrs_page_flip(struct intel_atomic_state *state, + struct intel_crtc *crtc) +{ + struct drm_i915_private *dev_priv = to_i915(state->base.dev); + unsigned int frontbuffer_bits = INTEL_FRONTBUFFER_ALL_MASK(crtc->pipe); + + intel_drrs_frontbuffer_update(dev_priv, frontbuffer_bits, false); +} + +/** + * intel_drrs_init - Init basic DRRS work and mutex. + * @connector: eDP connector + * @fixed_mode: preferred mode of panel + * + * This function is called only once at driver load to initialize basic + * DRRS stuff. + * + * Returns: + * Downclock mode if panel supports it, else return NULL. + * DRRS support is determined by the presence of downclock mode (apart + * from VBT setting). + */ +struct drm_display_mode * +intel_drrs_init(struct intel_connector *connector, + struct drm_display_mode *fixed_mode) +{ + struct drm_i915_private *dev_priv = to_i915(connector->base.dev); + struct drm_display_mode *downclock_mode = NULL; + + INIT_DELAYED_WORK(&dev_priv->drrs.work, intel_drrs_downclock_work); + mutex_init(&dev_priv->drrs.mutex); + + if (DISPLAY_VER(dev_priv) <= 6) { + drm_dbg_kms(&dev_priv->drm, + "DRRS supported for Gen7 and above\n"); + return NULL; + } + + if (dev_priv->vbt.drrs_type != SEAMLESS_DRRS_SUPPORT) { + drm_dbg_kms(&dev_priv->drm, "VBT doesn't support DRRS\n"); + return NULL; + } + + downclock_mode = intel_panel_edid_downclock_mode(connector, fixed_mode); + if (!downclock_mode) { + drm_dbg_kms(&dev_priv->drm, + "Downclock mode is not found. DRRS not supported\n"); + return NULL; + } + + dev_priv->drrs.type = dev_priv->vbt.drrs_type; + + dev_priv->drrs.refresh_rate_type = DRRS_HIGH_RR; + drm_dbg_kms(&dev_priv->drm, + "seamless DRRS supported for eDP panel.\n"); + return downclock_mode; +} |