[PATCH v5 4/8] drm/i915/pxp: Add GSC-CS backend to send GSC fw messages

[Teres Alexis, Alan Previn]

On Tue, 2023-02-14 at 13:38 -0800, Teres Alexis, Alan Previn wrote:
alan:snip
> +static int gsccs_send_message(struct intel_pxp *pxp,
> +			      void *msg_in, size_t msg_in_size,
> +			      void *msg_out, size_t msg_out_size_max,
> +			      size_t *msg_out_len,
> +			      u64 *gsc_msg_handle_retry)
> +{
> +	struct intel_gt *gt = pxp->ctrl_gt;
> +	struct drm_i915_private *i915 = gt->i915;
> +	struct gsccs_session_resources *exec =  &pxp->gsccs_res;
> +	struct intel_gsc_mtl_header *header = exec->pkt_vaddr;
> +	struct intel_gsc_heci_non_priv_pkt pkt;
> +	bool null_pkt = !msg_in && !msg_out;
> +	size_t max_msg_size;
> +	u32 reply_size;
> +	int ret;
> +
> +	if (!exec->ce)
> +		return -ENODEV;
> +
> +	max_msg_size = PXP43_MAX_HECI_IN_SIZE - sizeof(*header);
> +
> +	if (msg_in_size > max_msg_size || msg_out_size_max > max_msg_size)
> +		return -ENOSPC;
> +
> +	mutex_lock(&pxp->tee_mutex);
> +
> +	if (!exec->pkt_vma || !exec->bb_vma)
> +		return -ENOENT;
> +
alan: nack - i need to move the tee_mutex to after this pkt_vma / bb_bma checks