From 832dba889e27487c3087149f1039acc3feb89003 Mon Sep 17 00:00:00 2001 From: Patrik Jakobsson Date: Thu, 18 Feb 2016 17:21:11 +0200 Subject: [PATCH] drm/i915/gen9: Check for DC state mismatch The DMC can incorrectly run off and allow DC states on it's own. We don't know the root-cause for this yet but this patch makes it more visible. Reviewed-by: Mika Kuoppala Signed-off-by: Patrik Jakobsson Signed-off-by: Imre Deak Link: http://patchwork.freedesktop.org/patch/msgid/1455808874-22089-2-git-send-email-mika.kuoppala@intel.com --- drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/intel_csr.c | 2 ++ drivers/gpu/drm/i915/intel_runtime_pm.c | 8 ++++++++ 3 files changed, 11 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 6644c2e354c1..9cbcb5d80b3c 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -746,6 +746,7 @@ struct intel_csr { uint32_t mmio_count; i915_reg_t mmioaddr[8]; uint32_t mmiodata[8]; + uint32_t dc_state; }; #define DEV_INFO_FOR_EACH_FLAG(func, sep) \ diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c index 2a7ec3141c8d..b453fccfa25d 100644 --- a/drivers/gpu/drm/i915/intel_csr.c +++ b/drivers/gpu/drm/i915/intel_csr.c @@ -243,6 +243,8 @@ void intel_csr_load_program(struct drm_i915_private *dev_priv) I915_WRITE(dev_priv->csr.mmioaddr[i], dev_priv->csr.mmiodata[i]); } + + dev_priv->csr.dc_state = 0; } static uint32_t *parse_csr_fw(struct drm_i915_private *dev_priv, diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c index a2e367cf99a2..8b9290fdb3b2 100644 --- a/drivers/gpu/drm/i915/intel_runtime_pm.c +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c @@ -494,10 +494,18 @@ static void gen9_set_dc_state(struct drm_i915_private *dev_priv, uint32_t state) val = I915_READ(DC_STATE_EN); DRM_DEBUG_KMS("Setting DC state from %02x to %02x\n", val & mask, state); + + /* Check if DMC is ignoring our DC state requests */ + if ((val & mask) != dev_priv->csr.dc_state) + DRM_ERROR("DC state mismatch (0x%x -> 0x%x)\n", + dev_priv->csr.dc_state, val & mask); + val &= ~mask; val |= state; I915_WRITE(DC_STATE_EN, val); POSTING_READ(DC_STATE_EN); + + dev_priv->csr.dc_state = val & mask; } void bxt_enable_dc9(struct drm_i915_private *dev_priv) -- 2.20.1