From 47701c3ba26cb33ebe8a5e899ec922ab0de621a3 Mon Sep 17 00:00:00 2001 From: Paulo Zanoni Date: Tue, 23 Jul 2013 11:19:25 -0300 Subject: [PATCH] drm/i915: disable CLKOUT_DP when it's not needed We currently don't support HDMI clock bending nor use SSC for DP or HDMI on Haswell, so the only case where we need CLKOUT_DP is for VGA. v2: - Replace the IS_ULT check for LPT-LP - Simplify GEN0/DBUFF0 check due to change on the previous patch - Also check for SBI_SSCCTL_DISABLE (Ben). Reviewed-by: Ben Widawsky Signed-off-by: Paulo Zanoni Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_display.c | 36 ++++++++++++++++++++++++---- 1 file changed, 32 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 22e3f341366..26b49d8d781 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -5310,6 +5310,34 @@ static void lpt_enable_clkout_dp(struct drm_device *dev, bool with_spread, mutex_unlock(&dev_priv->dpio_lock); } +/* Sequence to disable CLKOUT_DP */ +static void lpt_disable_clkout_dp(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + uint32_t reg, tmp; + + mutex_lock(&dev_priv->dpio_lock); + + reg = (dev_priv->pch_id == INTEL_PCH_LPT_LP_DEVICE_ID_TYPE) ? + SBI_GEN0 : SBI_DBUFF0; + tmp = intel_sbi_read(dev_priv, reg, SBI_ICLK); + tmp &= ~SBI_GEN0_CFG_BUFFENABLE_DISABLE; + intel_sbi_write(dev_priv, reg, tmp, SBI_ICLK); + + tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK); + if (!(tmp & SBI_SSCCTL_DISABLE)) { + if (!(tmp & SBI_SSCCTL_PATHALT)) { + tmp |= SBI_SSCCTL_PATHALT; + intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK); + udelay(32); + } + tmp |= SBI_SSCCTL_DISABLE; + intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK); + } + + mutex_unlock(&dev_priv->dpio_lock); +} + static void lpt_init_pch_refclk(struct drm_device *dev) { struct drm_mode_config *mode_config = &dev->mode_config; @@ -5324,10 +5352,10 @@ static void lpt_init_pch_refclk(struct drm_device *dev) } } - if (!has_vga) - return; - - lpt_enable_clkout_dp(dev, true, true); + if (has_vga) + lpt_enable_clkout_dp(dev, true, true); + else + lpt_disable_clkout_dp(dev); } /* -- 2.41.0