diff options
Diffstat (limited to 'drivers/gpu/drm')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_hdcp.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c index 14ca5d3057a7..f2cf2e3acd3c 100644 --- a/drivers/gpu/drm/i915/intel_hdcp.c +++ b/drivers/gpu/drm/i915/intel_hdcp.c @@ -506,15 +506,26 @@ static int intel_hdcp_auth(struct intel_digital_port *intel_dig_port, */ wait_remaining_ms_from_jiffies(r0_prime_gen_start, 300); - ri.reg = 0; - ret = shim->read_ri_prime(intel_dig_port, ri.shim); - if (ret) - return ret; - I915_WRITE(PORT_HDCP_RPRIME(port), ri.reg); + tries = 3; - /* Wait for Ri prime match */ - if (wait_for(I915_READ(PORT_HDCP_STATUS(port)) & - (HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC), 1)) { + /* + * DP HDCP Spec mandates the two more reattempt to read R0, incase + * of R0 mismatch. + */ + for (i = 0; i < tries; i++) { + ri.reg = 0; + ret = shim->read_ri_prime(intel_dig_port, ri.shim); + if (ret) + return ret; + I915_WRITE(PORT_HDCP_RPRIME(port), ri.reg); + + /* Wait for Ri prime match */ + if (!wait_for(I915_READ(PORT_HDCP_STATUS(port)) & + (HDCP_STATUS_RI_MATCH | HDCP_STATUS_ENC), 1)) + break; + } + + if (i == tries) { DRM_ERROR("Timed out waiting for Ri prime match (%x)\n", I915_READ(PORT_HDCP_STATUS(port))); return -ETIMEDOUT; |