Re: [PATCH 14/24] drm/i915: account for only one PCH receiver on Haswell

[Jesse Barnes <jbarnes@virtuousgeek.org>]

On Thu, 26 Apr 2012 15:21:09 -0300
Eugeni Dodonov <eugeni.dodonov@intel.com> wrote:

> On Haswell, only one pipe can work in FDI mode, so this patch prevents
> messing with wrong registers when FDI is being used by non-first pipe.
> 
> Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c |   19 ++++++++++++++++---
>  1 file changed, 16 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index b2d3dc1..6509402 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -978,9 +978,14 @@ static void assert_fdi_rx(struct drm_i915_private *dev_priv,
>  	u32 val;
>  	bool cur_state;
>  
> -	reg = FDI_RX_CTL(pipe);
> -	val = I915_READ(reg);
> -	cur_state = !!(val & FDI_RX_ENABLE);
> +	if (IS_HASWELL(dev_priv->dev) && pipe > 0) {
> +			DRM_ERROR("Attempting to enable FDI_RX on Haswell pipe > 0\n");
> +			return;
> +	} else {
> +		reg = FDI_RX_CTL(pipe);
> +		val = I915_READ(reg);
> +		cur_state = !!(val & FDI_RX_ENABLE);
> +	}
>  	WARN(cur_state != state,
>  	     "FDI RX state assertion failure (expected %s, current %s)\n",
>  	     state_string(state), state_string(cur_state));
> @@ -1013,6 +1018,10 @@ static void assert_fdi_rx_pll_enabled(struct drm_i915_private *dev_priv,
>  	int reg;
>  	u32 val;
>  
> +	if (IS_HASWELL(dev_priv->dev) && pipe > 0) {
> +		DRM_ERROR("Attempting to enable FDI on Haswell with pipe > 0\n");
> +		return;
> +	}
>  	reg = FDI_RX_CTL(pipe);
>  	val = I915_READ(reg);
>  	WARN(!(val & FDI_RX_PLL_ENABLE), "FDI RX PLL assertion failure, should be active but is disabled\n");
> @@ -1484,6 +1493,10 @@ static void intel_enable_transcoder(struct drm_i915_private *dev_priv,
>  	assert_fdi_tx_enabled(dev_priv, pipe);
>  	assert_fdi_rx_enabled(dev_priv, pipe);
>  
> +	if (IS_HASWELL(dev_priv->dev) && pipe > 0) {
> +		DRM_ERROR("Attempting to enable transcoder on Haswell with pipe > 0\n");
> +		return;
> +	}
>  	reg = TRANSCONF(pipe);
>  	val = I915_READ(reg);
>  	pipeconf_val = I915_READ(PIPECONF(pipe));

Yuck...  good thing only VGA is on the PCH.

If you don't end up doing separate high level functions for this:

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>

-- 
Jesse Barnes, Intel Open Source Technology Center