In case of V prime mismatch, DP HDCP spec mandates the re-read of
Vprime atleast twice.
Fixes DP HDCP CTS Test: 1B-05
v2:
Moved the V' validation into a function for retry. [Sean Paul]
Signed-off-by: Ramalingam C <ramalinga...@intel.com>
---
drivers/gpu/drm/i915/intel_hdcp.c | 113 +++++++++++++++++++++++---------------
1 file changed, 70 insertions(+), 43 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_hdcp.c
b/drivers/gpu/drm/i915/intel_hdcp.c
index 730681d2dbfb..3a02463d2b7a 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)
+static inline
+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 +317,7 @@ 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("Invalid number of leftovers %d\n", sha_leftovers);
return -EINVAL;
}
@@ -381,14 +345,77 @@ 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("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("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
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
