[Intel-gfx] [RFC-v19 02/13] drm/i915/pxp: set KCR reg init during the boot time

[Vivi, Rodrigo]

On Wed, 2021-01-06 at 15:12 -0800, Huang, Sean Z wrote:
> Set the KCR init during the boot time, which is
> required by hardware, to allow us doing further
> protection operation such as sending commands to
> GPU or TEE.
> 
> Signed-off-by: Huang, Sean Z <sean.z.huang at intel.com>
> ---
>  drivers/gpu/drm/i915/pxp/intel_pxp.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c
> b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> index 9bc3c7e30654..f566a4fda044 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> @@ -6,6 +6,12 @@
>  #include "intel_pxp.h"
>  #include "intel_pxp_context.h"
>  
> +/* KCR register definitions */

please define this in i915_reg.h

> +#define KCR_INIT            _MMIO(0x320f0)
> +#define KCR_INIT_MASK_SHIFT (16) 

mask or shift?

> +/* Setting KCR Init bit is required after system boot */
> +#define KCR_INIT_ALLOW_DISPLAY_ME_WRITES (BIT(14) | (BIT(14) <<
> KCR_INIT_MASK_SHIFT))

Also, use only bit definitions here and leave the mask and/or shift
only when calling the write function.

> 
> +
>  void intel_pxp_init(struct intel_pxp *pxp)
>  {
>         struct intel_gt *gt = container_of(pxp, struct intel_gt,
> pxp);
> @@ -15,6 +21,8 @@ void intel_pxp_init(struct intel_pxp *pxp)
>  
>         intel_pxp_ctx_init(&pxp->ctx);
>  
> +       intel_uncore_write(gt->uncore, KCR_INIT,
> KCR_INIT_ALLOW_DISPLAY_ME_WRITES);
> +
>         drm_info(&gt->i915->drm, "Protected Xe Path (PXP) protected
> content support initialized\n");
>  }
>