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 <ben@bwidawsk.net>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Paulo Zanoni 2013-07-23 11:19:25 -03:00 committed by Daniel Vetter
parent 2fa86a1fea
commit 47701c3ba2
1 changed files with 32 additions and 4 deletions

View File

@ -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);
}
/*