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 ramalingam.c@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;