Re: [PATCH] drm/i915: clear the QGV mask set by GOP while booting

["Lisovskiy, Stanislav" <stanislav.lisovskiy@intel.com>]

On Wed, Jan 03, 2024 at 06:57:45PM -0800, George D Sworo wrote:
> From: George D Sworo <george.d.sworo@intel.com>
> 
> GOP driver in the firmware is masking the QGV points except the one
> which can
> provide high Bandwidth required for panel.
> 
> On boot to the OS the mask is already set, and is not cleared anywhere
> in the i915 driver
> even though sagv is enabled. This means Pcode is unable to switch to
> other QGV work points
> except the one enabled by default in the GOP driver at boot time.
> 
> This change resets the mask, when i915 driver is finding the QGV
> points at the boot time. So that Pcode can switch to QGV work points
> based
> on the Workloads.
> 
> Signed-off-by: George D Sworo <george.d.sworo@intel.com>


Hi,

We already have a case similar to this, you might want to check this out:

https://patchwork.freedesktop.org/series/126962/

Stan


> ---
>  drivers/gpu/drm/i915/display/intel_bw.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
> index bef96db62c80..e2576c0fb729 100644
> --- a/drivers/gpu/drm/i915/display/intel_bw.c
> +++ b/drivers/gpu/drm/i915/display/intel_bw.c
> @@ -212,6 +212,7 @@ static int icl_get_qgv_points(struct drm_i915_private *dev_priv,
>  			      bool is_y_tile)
>  {
>  	const struct dram_info *dram_info = &dev_priv->dram_info;
> +	u32 val = 0x00, val2 = 0;
>  	int i, ret;
>  
>  	qi->num_points = dram_info->num_qgv_points;
> @@ -311,6 +312,11 @@ static int icl_get_qgv_points(struct drm_i915_private *dev_priv,
>  				    i, qi->psf_points[i].clk);
>  	}
>  
> +	/* clear the QGV points mask set by the GOP driver while booting */
> +	ret = snb_pcode_read(&dev_priv->uncore, ICL_PCODE_SAGV_DE_MEM_SS_CONFIG, &val, &val2);
> +	if (ret)
> +		return ret;
> +
>  	return 0;
>  }
>  
> -- 
> 2.34.1
>