Re: [PATCH 7/8] drm/i915: Reauthenticate HDCP on failure

Ramalingam C
2018-02-02T15:10:43Z

On Friday 02 February 2018 08:07 PM, Sean Paul wrote:
> On Fri, Feb 02, 2018 at 04:15:19PM +0530, Ramalingam C wrote:
>> When HDCP authentication fails, we add two more reauthentication.
>> This will address all reauth expectation from compliance perspective.
>>
>> Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
>> ---
>> drivers/gpu/drm/i915/intel_hdcp.c | 18 +++++++++++-------
>> 1 file changed, 11 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c
>> index a3463557f0f6..3caa548a9cad 100644
>> --- a/drivers/gpu/drm/i915/intel_hdcp.c
>> +++ b/drivers/gpu/drm/i915/intel_hdcp.c
>> @@ -566,7 +566,7 @@ static int _intel_hdcp_disable(struct intel_connector *connector)
>> static int _intel_hdcp_enable(struct intel_connector *connector)
>> {
>> struct drm_i915_private *dev_priv = connector->base.dev->dev_private;
>> - int i, ret;
>> + int i, ret, reauth = 1;
>>
>> if (!(I915_READ(SKL_FUSE_STATUS) & SKL_FUSE_PG_DIST_STATUS(1))) {
>> DRM_ERROR("PG1 is disabled, cannot load keys\n");
>> @@ -584,13 +584,17 @@ static int _intel_hdcp_enable(struct intel_connector *connector)
>> return ret;
>> }
>>
>> - ret = intel_hdcp_auth(connector);
>> - if (ret) {
>> - DRM_ERROR("Failed to authenticate HDCP (%d)\n", ret);
>> - return ret;
>> - }
>> + do {
>> + ret = intel_hdcp_auth(connector);
>> + if (ret)
>> + DRM_ERROR("Failed to authenticate HDCP (%d)\n", ret);
>> + if (ret && reauth)
>> + DRM_DEBUG_KMS("[%s:%d] HDCP Reauth... %d/1\n",
>> + connector->base.name,
>> + connector->base.base.id, reauth);
>> + } while (ret && reauth--);
>>
>> - return 0;
>> + return ret;
>
> I think we can do something a little more straightforward, like:
>
> int i, ret, tries = 2;
>
> for (i = 0; i < tries; i++) {
> ret = intel_hdcp_auth(...);
> if (!ret)
> return 0;
>
> DRM_DEBUG_KMS("[%s:%d] HDCP Auth failure (%d)\n",
> connector->base.name, connector->base.base.id,
> ret);
> }
>
> DRM_ERROR("[%s:%d] HDCP authentication failed (%d tries/%d)\n",
> connector->base.name, connector->base.base.id, tries, ret);
> _intel_hdcp_disable(...);
> return ret;
>
Sure. I will do it.

-Ram
>> }
>>
>> static void intel_hdcp_check_work(struct work_struct *work)
>> --
>> 2.7.4
>>