From 4e961e426cdeb5c9f27d65fb0afb0010fcecfeae Mon Sep 17 00:00:00 2001 From: Animesh Manna Date: Wed, 26 Aug 2015 01:36:08 +0530 Subject: [PATCH] drm/i915/skl: Do not disable cdclk PLL if csr firmware is present While display engine entering into low power state no need to disable cdclk pll as CSR firmware of dmc will take care. If pll is already enabled firmware execution sequence will be blocked. This is one of the criteria for dmc to work properly. v1: Initial version. v2: Based on review comment from Daniel added code commnent. Cc: Daniel Vetter Cc: Damien Lespiau Cc: Imre Deak Cc: Sunil Kamath Signed-off-by: Animesh Manna Signed-off-bt: Vathsala Nagaraju Signed-off-by: Rajneesh Bhardwaj Reviewed-by: A.Sunil Kamath Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_display.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 1847257..5d8645e 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -5709,10 +5709,16 @@ void skl_uninit_cdclk(struct drm_i915_private *dev_priv) if (I915_READ(DBUF_CTL) & DBUF_POWER_STATE) DRM_ERROR("DBuf power disable timeout\n"); - /* disable DPLL0 */ - I915_WRITE(LCPLL1_CTL, I915_READ(LCPLL1_CTL) & ~LCPLL_PLL_ENABLE); - if (wait_for(!(I915_READ(LCPLL1_CTL) & LCPLL_PLL_LOCK), 1)) - DRM_ERROR("Couldn't disable DPLL0\n"); + /* + * DMC assumes ownership of LCPLL and will get confused if we touch it. + */ + if (dev_priv->csr.dmc_payload) { + /* disable DPLL0 */ + I915_WRITE(LCPLL1_CTL, I915_READ(LCPLL1_CTL) & + ~LCPLL_PLL_ENABLE); + if (wait_for(!(I915_READ(LCPLL1_CTL) & LCPLL_PLL_LOCK), 1)) + DRM_ERROR("Couldn't disable DPLL0\n"); + } intel_display_power_put(dev_priv, POWER_DOMAIN_PLLS); } -- 2.7.4