The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 6ac43272768ca901daac4076a66c2c4e3c7b9321 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= ville.syrjala@linux.intel.com Date: Wed, 8 Nov 2017 15:35:55 +0200 Subject: [PATCH] drm/i915: Move init_clock_gating() back to where it was MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

Apparently setting up a bunch of GT registers before we've properly initialized the rest of the GT hardware leads to these setting being lost. So looks like I broke HSW with commit b7048ea12fbb ("drm/i915: Do .init_clock_gating() earlier to avoid it clobbering watermarks") by doing init_clock_gating() too early. This should actually affect other platforms as well, but apparently not to such a great degree.

What I was ultimately after in that commit was to move the ilk_init_lp_watermarks() call earlier. So let's undo the damage and move init_clock_gating() back to where it was, and call ilk_init_lp_watermarks() just before the watermark state readout.

This highlights how fragile and messed up our init order really is. I wonder why we even initialize the display before gem. The opposite order would make much more sense to me...

v2: Keep WaRsPkgCStateDisplayPMReq:hsw early as it really must be done before all planes might get disabled.

Cc: stable@vger.kernel.org Cc: Chris Wilson chris@chris-wilson.co.uk Cc: Mark Janes mark.a.janes@intel.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com Cc: Oscar Mateo oscar.mateo@intel.com Cc: Mika Kuoppala mika.kuoppala@linux.intel.com Reported-by: Mark Janes mark.a.janes@intel.com Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103549 Fixes: b7048ea12fbb ("drm/i915: Do .init_clock_gating() earlier to avoid it clobbering watermarks") References: https://lists.freedesktop.org/archives/intel-gfx/2017-November/145432.html Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20171108133555.14091-1-ville.s... Tested-by: Chris Wilson chris@chris-wilson.co.uk Reviewed-by: Chris Wilson chris@chris-wilson.co.uk (cherry picked from commit f72b84c677d61f201b869223a8d6e389c7bb7d3d) Signed-off-by: Jani Nikula jani.nikula@intel.com

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index e2ac976844d8..f4a9a182868f 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -3676,6 +3676,7 @@ void intel_finish_reset(struct drm_i915_private *dev_priv)

intel_pps_unlock_regs_wa(dev_priv); intel_modeset_init_hw(dev); + intel_init_clock_gating(dev_priv);

spin_lock_irq(&dev_priv->irq_lock); if (dev_priv->display.hpd_irq_setup) @@ -14350,8 +14351,6 @@ void intel_modeset_init_hw(struct drm_device *dev)

intel_update_cdclk(dev_priv); dev_priv->cdclk.logical = dev_priv->cdclk.actual = dev_priv->cdclk.hw; - - intel_init_clock_gating(dev_priv); }

/* @@ -15063,6 +15062,15 @@ intel_modeset_setup_hw_state(struct drm_device *dev, struct intel_encoder *encoder; int i;

+ if (IS_HASWELL(dev_priv)) { + /* + * WaRsPkgCStateDisplayPMReq:hsw + * System hang if this isn't done before disabling all planes! + */ + I915_WRITE(CHICKEN_PAR1_1, + I915_READ(CHICKEN_PAR1_1) | FORCE_ARB_IDLE_PLANES); + } + intel_modeset_readout_hw_state(dev);

/* HW state is read out, now we need to sanitize this mess. */ @@ -15160,6 +15168,8 @@ void intel_modeset_gem_init(struct drm_device *dev)

intel_init_gt_powersave(dev_priv);

+ intel_init_clock_gating(dev_priv); + intel_setup_overlay(dev_priv); }

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 7d2ecabc5de5..aa12a44e9a76 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -5762,12 +5762,30 @@ void vlv_wm_sanitize(struct drm_i915_private *dev_priv) mutex_unlock(&dev_priv->wm.wm_mutex); }

+/* + * FIXME should probably kill this and improve + * the real watermark readout/sanitation instead + */ +static void ilk_init_lp_watermarks(struct drm_i915_private *dev_priv) +{ + I915_WRITE(WM3_LP_ILK, I915_READ(WM3_LP_ILK) & ~WM1_LP_SR_EN); + I915_WRITE(WM2_LP_ILK, I915_READ(WM2_LP_ILK) & ~WM1_LP_SR_EN); + I915_WRITE(WM1_LP_ILK, I915_READ(WM1_LP_ILK) & ~WM1_LP_SR_EN); + + /* + * Don't touch WM1S_LP_EN here. + * Doing so could cause underruns. + */ +} + void ilk_wm_get_hw_state(struct drm_device *dev) { struct drm_i915_private *dev_priv = to_i915(dev); struct ilk_wm_values *hw = &dev_priv->wm.hw; struct drm_crtc *crtc;

+ ilk_init_lp_watermarks(dev_priv); + for_each_crtc(dev, crtc) ilk_pipe_wm_get_hw_state(crtc);

@@ -8214,18 +8232,6 @@ static void g4x_disable_trickle_feed(struct drm_i915_private *dev_priv) } }

-static void ilk_init_lp_watermarks(struct drm_i915_private *dev_priv) -{ - I915_WRITE(WM3_LP_ILK, I915_READ(WM3_LP_ILK) & ~WM1_LP_SR_EN); - I915_WRITE(WM2_LP_ILK, I915_READ(WM2_LP_ILK) & ~WM1_LP_SR_EN); - I915_WRITE(WM1_LP_ILK, I915_READ(WM1_LP_ILK) & ~WM1_LP_SR_EN); - - /* - * Don't touch WM1S_LP_EN here. - * Doing so could cause underruns. - */ -} - static void ilk_init_clock_gating(struct drm_i915_private *dev_priv) { uint32_t dspclk_gate = ILK_VRHUNIT_CLOCK_GATE_DISABLE; @@ -8259,8 +8265,6 @@ static void ilk_init_clock_gating(struct drm_i915_private *dev_priv) (I915_READ(DISP_ARB_CTL) | DISP_FBC_WM_DIS));

- ilk_init_lp_watermarks(dev_priv); - /* * Based on the document from hardware guys the following bits * should be set unconditionally in order to enable FBC. @@ -8373,8 +8377,6 @@ static void gen6_init_clock_gating(struct drm_i915_private *dev_priv) I915_WRITE(GEN6_GT_MODE, _MASKED_FIELD(GEN6_WIZ_HASHING_MASK, GEN6_WIZ_HASHING_16x4));

- ilk_init_lp_watermarks(dev_priv); - I915_WRITE(CACHE_MODE_0, _MASKED_BIT_DISABLE(CM0_STC_EVICT_DISABLE_LRA_SNB));

@@ -8601,8 +8603,6 @@ static void bdw_init_clock_gating(struct drm_i915_private *dev_priv) I915_GTT_PAGE_SIZE_2M); enum pipe pipe;

- ilk_init_lp_watermarks(dev_priv); - /* WaSwitchSolVfFArbitrationPriority:bdw */ I915_WRITE(GAM_ECOCHK, I915_READ(GAM_ECOCHK) | HSW_ECOCHK_ARB_PRIO_SOL);

@@ -8653,8 +8653,6 @@ static void bdw_init_clock_gating(struct drm_i915_private *dev_priv)

static void hsw_init_clock_gating(struct drm_i915_private *dev_priv) { - ilk_init_lp_watermarks(dev_priv); - /* L3 caching of data atomics doesn't work -- disable it. */ I915_WRITE(HSW_SCRATCH1, HSW_SCRATCH1_L3_DATA_ATOMICS_DISABLE); I915_WRITE(HSW_ROW_CHICKEN3, @@ -8698,10 +8696,6 @@ static void hsw_init_clock_gating(struct drm_i915_private *dev_priv) /* WaSwitchSolVfFArbitrationPriority:hsw */ I915_WRITE(GAM_ECOCHK, I915_READ(GAM_ECOCHK) | HSW_ECOCHK_ARB_PRIO_SOL);

- /* WaRsPkgCStateDisplayPMReq:hsw */ - I915_WRITE(CHICKEN_PAR1_1, - I915_READ(CHICKEN_PAR1_1) | FORCE_ARB_IDLE_PLANES); - lpt_init_clock_gating(dev_priv); }

@@ -8709,8 +8703,6 @@ static void ivb_init_clock_gating(struct drm_i915_private *dev_priv) { uint32_t snpcr;

- ilk_init_lp_watermarks(dev_priv); - I915_WRITE(ILK_DSPCLK_GATE_D, ILK_VRHUNIT_CLOCK_GATE_DISABLE);

/* WaDisableEarlyCull:ivb */