On Mon, Apr 02, 2018 at 03:40:32PM +0530, Ramalingam C wrote:
> In case of V prime mismatch, DP HDCP spec mandates the re-read of
> Vprime atleast twice.
>
> This patch needed for DP HDCP1.4 CTS Test: 1B-05.
>
> v2:
> Moved the V' validation into a function for retry. [Sean Paul]
> v3:
> Removed Inline keyword and DRM_DEBUG_KMS are used [Sean Paul]
>
> Signed-off-by: Ramalingam C <ramalinga...@intel.com>
Reviewed-by: Sean Paul <seanp...@chromium.org>
> ---
> drivers/gpu/drm/i915/intel_hdcp.c | 112
> ++++++++++++++++++++++++--------------
> 1 file changed, 70 insertions(+), 42 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_hdcp.c
> b/drivers/gpu/drm/i915/intel_hdcp.c
> index 838c8cd0f543..e0bc03eee941 100644
> --- a/drivers/gpu/drm/i915/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/intel_hdcp.c
> @@ -142,53 +142,17 @@ bool intel_hdcp_is_ksv_valid(u8 *ksv)
> return true;
> }
>
> -/* Implements Part 2 of the HDCP authorization procedure */
> static
> -int intel_hdcp_auth_downstream(struct intel_digital_port *intel_dig_port,
> - const struct intel_hdcp_shim *shim)
> +int intel_hdcp_validate_v_prime(struct intel_digital_port *intel_dig_port,
> + const struct intel_hdcp_shim *shim,
> + u8 *ksv_fifo, u8 num_downstream, u8 *bstatus)
> {
> struct drm_i915_private *dev_priv;
> u32 vprime, sha_text, sha_leftovers, rep_ctl;
> - u8 bstatus[2], num_downstream, *ksv_fifo;
> int ret, i, j, sha_idx;
>
> dev_priv = intel_dig_port->base.base.dev->dev_private;
>
> - ret = intel_hdcp_poll_ksv_fifo(intel_dig_port, shim);
> - if (ret) {
> - DRM_ERROR("KSV list failed to become ready (%d)\n", ret);
> - return ret;
> - }
> -
> - ret = shim->read_bstatus(intel_dig_port, bstatus);
> - if (ret)
> - return ret;
> -
> - if (DRM_HDCP_MAX_DEVICE_EXCEEDED(bstatus[0]) ||
> - DRM_HDCP_MAX_CASCADE_EXCEEDED(bstatus[1])) {
> - DRM_ERROR("Max Topology Limit Exceeded\n");
> - return -EPERM;
> - }
> -
> - /*
> - * When repeater reports 0 device count, HDCP1.4 spec allows disabling
> - * the HDCP encryption. That implies that repeater can't have its own
> - * display. As there is no consumption of encrypted content in the
> - * repeater with 0 downstream devices, we are failing the
> - * authentication.
> - */
> - num_downstream = DRM_HDCP_NUM_DOWNSTREAM(bstatus[0]);
> - if (num_downstream == 0)
> - return -EINVAL;
> -
> - ksv_fifo = kzalloc(num_downstream * DRM_HDCP_KSV_LEN, GFP_KERNEL);
> - if (!ksv_fifo)
> - return -ENOMEM;
> -
> - ret = shim->read_ksv_fifo(intel_dig_port, num_downstream, ksv_fifo);
> - if (ret)
> - return ret;
> -
> /* Process V' values from the receiver */
> for (i = 0; i < DRM_HDCP_V_PRIME_NUM_PARTS; i++) {
> ret = shim->read_v_prime_part(intel_dig_port, i, &vprime);
> @@ -353,7 +317,8 @@ int intel_hdcp_auth_downstream(struct intel_digital_port
> *intel_dig_port,
> return ret;
> sha_idx += sizeof(sha_text);
> } else {
> - DRM_ERROR("Invalid number of leftovers %d\n", sha_leftovers);
> + DRM_DEBUG_KMS("Invalid number of leftovers %d\n",
> + sha_leftovers);
> return -EINVAL;
> }
>
> @@ -381,14 +346,77 @@ int intel_hdcp_auth_downstream(struct
> intel_digital_port *intel_dig_port,
> if (intel_wait_for_register(dev_priv, HDCP_REP_CTL,
> HDCP_SHA1_COMPLETE,
> HDCP_SHA1_COMPLETE, 1)) {
> - DRM_ERROR("Timed out waiting for SHA1 complete\n");
> + DRM_DEBUG_KMS("Timed out waiting for SHA1 complete\n");
> return -ETIMEDOUT;
> }
> if (!(I915_READ(HDCP_REP_CTL) & HDCP_SHA1_V_MATCH)) {
> - DRM_ERROR("SHA-1 mismatch, HDCP failed\n");
> + DRM_DEBUG_KMS("SHA-1 mismatch, HDCP failed\n");
> return -ENXIO;
> }
>
> + return 0;
> +}
> +
> +/* Implements Part 2 of the HDCP authorization procedure */
> +static
> +int intel_hdcp_auth_downstream(struct intel_digital_port *intel_dig_port,
> + const struct intel_hdcp_shim *shim)
> +{
> + u8 bstatus[2], num_downstream, *ksv_fifo;
> + int ret, i, tries = 3;
> +
> + ret = intel_hdcp_poll_ksv_fifo(intel_dig_port, shim);
> + if (ret) {
> + DRM_ERROR("KSV list failed to become ready (%d)\n", ret);
> + return ret;
> + }
> +
> + ret = shim->read_bstatus(intel_dig_port, bstatus);
> + if (ret)
> + return ret;
> +
> + if (DRM_HDCP_MAX_DEVICE_EXCEEDED(bstatus[0]) ||
> + DRM_HDCP_MAX_CASCADE_EXCEEDED(bstatus[1])) {
> + DRM_ERROR("Max Topology Limit Exceeded\n");
> + return -EPERM;
> + }
> +
> + /*
> + * When repeater reports 0 device count, HDCP1.4 spec allows disabling
> + * the HDCP encryption. That implies that repeater can't have its own
> + * display. As there is no consumption of encrypted content in the
> + * repeater with 0 downstream devices, we are failing the
> + * authentication.
> + */
> + num_downstream = DRM_HDCP_NUM_DOWNSTREAM(bstatus[0]);
> + if (num_downstream == 0)
> + return -EINVAL;
> +
> + ksv_fifo = kzalloc(num_downstream * DRM_HDCP_KSV_LEN, GFP_KERNEL);
> + if (!ksv_fifo)
> + return -ENOMEM;
> +
> + ret = shim->read_ksv_fifo(intel_dig_port, num_downstream, ksv_fifo);
> + if (ret)
> + return ret;
> +
> + /*
> + * When V prime mismatches, DP Spec mandates re-read of
> + * V prime atleast twice.
> + */
> + for (i = 0; i < tries; i++) {
> + ret = intel_hdcp_validate_v_prime(intel_dig_port, shim,
> + ksv_fifo, num_downstream,
> + bstatus);
> + if (!ret)
> + break;
> + }
> +
> + if (i == tries) {
> + DRM_ERROR("V Prime validation failed.(%d)\n", ret);
> + return ret;
> + }
> +
> DRM_DEBUG_KMS("HDCP is enabled (%d downstream devices)\n",
> num_downstream);
> return 0;
> --
> 2.7.4
>
--
Sean Paul, Software Engineer, Google / Chromium OS
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
