[Intel-gfx] [PATCH 1/5] drm/i915/chv: Remove Wait for a previous gfx force-off

[Ville Syrjälä]

On Thu, Feb 26, 2015 at 08:46:54PM +0530, deepak.s at linux.intel.com wrote:
> From: Deepak S <deepak.s at linux.intel.com>
> 
> On CHV, PUNIT team confirmed that 'VLV_GFX_CLK_STATUS_BIT' is not a
> sticky bit and it will always be set. So ignore Check for previous
> Gfx force off during suspend and allow the force clk as part S0ix
> Sequence

Do we need the force clock at all since we don't do any gunit register
save/restore? I tried to peddle a patch to remove it totally in this bug
report, but never got any decent answer back:
https://bugs.freedesktop.org/show_bug.cgi?id=87086

> 
> Signed-off-by: Deepak S <deepak.s at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 4badb23..b88b7b1 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -1193,11 +1193,13 @@ int vlv_force_gfx_clock(struct drm_i915_private *dev_priv, bool force_on)
>  	int err;
>  
>  	val = I915_READ(VLV_GTLC_SURVIVABILITY_REG);
> -	WARN_ON(!!(val & VLV_GFX_CLK_FORCE_ON_BIT) == force_on);
>  
>  #define COND (I915_READ(VLV_GTLC_SURVIVABILITY_REG) & VLV_GFX_CLK_STATUS_BIT)
>  	/* Wait for a previous force-off to settle */
> -	if (force_on) {
> +	if (force_on && !IS_CHERRYVIEW(dev_priv->dev)) {
> +		/* WARN_ON only for the Valleyview */
> +		WARN_ON(!!(val & VLV_GFX_CLK_FORCE_ON_BIT) == force_on);
> +
>  		err = wait_for(!COND, 20);
>  		if (err) {
>  			DRM_ERROR("timeout waiting for GFX clock force-off (%08x)\n",
> -- 
> 1.9.1

-- 
Ville Syrjälä
Intel OTC