From 58590c14d80defc94e900308a9d8fa55284de6f2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Tue, 8 Sep 2015 21:05:12 +0300 Subject: [PATCH] drm/i915: Don't try to use DDR DVFS on CHV when disabled in the BIOS MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If one disables DDR DVFS in the BIOS, Punit will apparently ignores all DDR DVFS request. Currently we assume that DDR DVFS is always operational, which leads to errors in dmesg when the DDR DVFS requests time out. Fix the problem by gently prodding Punit during driver load to find out whether it will respond to DDR DVFS requests. If the request times out, we assume that DDR DVFS has been permanenly disabled in the BIOS and no longer perster the Punit about it. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91629 Signed-off-by: Ville Syrjälä Reviewed-by: Clint Taylor Tested-by: Clint Taylor Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/i915_drv.h | 2 ++ drivers/gpu/drm/i915/intel_pm.c | 42 +++++++++++++++++++++++---------- 2 files changed, 31 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 522da7b12a882f..b06e0308077193 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1928,6 +1928,8 @@ struct drm_i915_private { struct skl_wm_values skl_hw; struct vlv_wm_values vlv; }; + + uint8_t max_level; } wm; struct i915_runtime_pm pm; diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index fff0c22682ee32..ddbb7ed0a19322 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -955,8 +955,6 @@ enum vlv_wm_level { VLV_WM_LEVEL_PM2, VLV_WM_LEVEL_PM5, VLV_WM_LEVEL_DDR_DVFS, - CHV_WM_NUM_LEVELS, - VLV_WM_NUM_LEVELS = 1, }; /* latency must be in 0.1us units. */ @@ -982,9 +980,13 @@ static void vlv_setup_wm_latency(struct drm_device *dev) /* all latencies in usec */ dev_priv->wm.pri_latency[VLV_WM_LEVEL_PM2] = 3; + dev_priv->wm.max_level = VLV_WM_LEVEL_PM2; + if (IS_CHERRYVIEW(dev_priv)) { dev_priv->wm.pri_latency[VLV_WM_LEVEL_PM5] = 12; dev_priv->wm.pri_latency[VLV_WM_LEVEL_DDR_DVFS] = 33; + + dev_priv->wm.max_level = VLV_WM_LEVEL_DDR_DVFS; } } @@ -1137,10 +1139,7 @@ static void vlv_compute_wm(struct intel_crtc *crtc) memset(wm_state, 0, sizeof(*wm_state)); wm_state->cxsr = crtc->pipe != PIPE_C && crtc->wm.cxsr_allowed; - if (IS_CHERRYVIEW(dev)) - wm_state->num_levels = CHV_WM_NUM_LEVELS; - else - wm_state->num_levels = VLV_WM_NUM_LEVELS; + wm_state->num_levels = to_i915(dev)->wm.max_level + 1; wm_state->num_active_planes = 0; @@ -1220,7 +1219,7 @@ static void vlv_compute_wm(struct intel_crtc *crtc) } /* clear any (partially) filled invalid levels */ - for (level = wm_state->num_levels; level < CHV_WM_NUM_LEVELS; level++) { + for (level = wm_state->num_levels; level < to_i915(dev)->wm.max_level + 1; level++) { memset(&wm_state->wm[level], 0, sizeof(wm_state->wm[level])); memset(&wm_state->sr[level], 0, sizeof(wm_state->sr[level])); } @@ -1324,10 +1323,7 @@ static void vlv_merge_wm(struct drm_device *dev, struct intel_crtc *crtc; int num_active_crtcs = 0; - if (IS_CHERRYVIEW(dev)) - wm->level = VLV_WM_LEVEL_DDR_DVFS; - else - wm->level = VLV_WM_LEVEL_PM2; + wm->level = to_i915(dev)->wm.max_level; wm->cxsr = true; for_each_intel_crtc(dev, crtc) { @@ -4083,9 +4079,29 @@ void vlv_wm_get_hw_state(struct drm_device *dev) if (val & DSP_MAXFIFO_PM5_ENABLE) wm->level = VLV_WM_LEVEL_PM5; + /* + * If DDR DVFS is disabled in the BIOS, Punit + * will never ack the request. So if that happens + * assume we don't have to enable/disable DDR DVFS + * dynamically. To test that just set the REQ_ACK + * bit to poke the Punit, but don't change the + * HIGH/LOW bits so that we don't actually change + * the current state. + */ val = vlv_punit_read(dev_priv, PUNIT_REG_DDR_SETUP2); - if ((val & FORCE_DDR_HIGH_FREQ) == 0) - wm->level = VLV_WM_LEVEL_DDR_DVFS; + val |= FORCE_DDR_FREQ_REQ_ACK; + vlv_punit_write(dev_priv, PUNIT_REG_DDR_SETUP2, val); + + if (wait_for((vlv_punit_read(dev_priv, PUNIT_REG_DDR_SETUP2) & + FORCE_DDR_FREQ_REQ_ACK) == 0, 3)) { + DRM_DEBUG_KMS("Punit not acking DDR DVFS request, " + "assuming DDR DVFS is disabled\n"); + dev_priv->wm.max_level = VLV_WM_LEVEL_PM5; + } else { + val = vlv_punit_read(dev_priv, PUNIT_REG_DDR_SETUP2); + if ((val & FORCE_DDR_HIGH_FREQ) == 0) + wm->level = VLV_WM_LEVEL_DDR_DVFS; + } mutex_unlock(&dev_priv->rps.hw_lock); }