Re: [PATCH 4/4] drm/i915: Increase timeout for Encrypt status change

From: Sean Paul <sean@poorly.run>
To: Ramalingam C <ramalingam.c@intel.com>
Cc: daniel.vetter@ffwll.ch, intel-gfx@lists.freedesktop.org,
	seanpaul@chromium.org, dri-devel@lists.freedesktop.org
Subject: Re: [PATCH 4/4] drm/i915: Increase timeout for Encrypt status change
Date: Mon, 3 Dec 2018 09:27:37 -0500	[thread overview]
Message-ID: <20181203142737.GP154160@art_vandelay> (raw)
In-Reply-To: <1543327379-22629-5-git-send-email-ramalingam.c@intel.com>

On Tue, Nov 27, 2018 at 07:32:59PM +0530, Ramalingam C wrote:
> At enable/disable of the HDCP encryption, for encryption status change
> we need minimum one frame duration. And we might program this bit any
> point(start/End) in the previous frame.
> 
> With 20mSec, observed the timeout for change in encryption status.
> Since this is not time critical operation and we need to hold on
> until the status is changed, fixing the timeout to 50mSec. (Based on
> trial and error method!)
> 
> Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_hdcp.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c
> index bd60d0e7bbfa..156b14d19e09 100644
> --- a/drivers/gpu/drm/i915/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/intel_hdcp.c
> @@ -15,6 +15,7 @@
>  #include "i915_reg.h"
>  
>  #define KEY_LOAD_TRIES	5
> +#define TIME_FOR_ENCRYPT_STATUS_CHANGE	50

ENCRYPT_STATUS_CHANGE_TIMEOUT_MS please

with that fixed,

Reviewed-by: Sean Paul <sean@poorly.run>


>  
>  static
>  bool intel_hdcp_is_ksv_valid(u8 *ksv)
> @@ -638,7 +639,8 @@ static int intel_hdcp_auth(struct intel_digital_port *intel_dig_port,
>  
>  	/* Wait for encryption confirmation */
>  	if (intel_wait_for_register(dev_priv, PORT_HDCP_STATUS(port),
> -				    HDCP_STATUS_ENC, HDCP_STATUS_ENC, 20)) {
> +				    HDCP_STATUS_ENC, HDCP_STATUS_ENC,
> +				    TIME_FOR_ENCRYPT_STATUS_CHANGE)) {
>  		DRM_ERROR("Timed out waiting for encryption\n");
>  		return -ETIMEDOUT;
>  	}
> @@ -668,7 +670,7 @@ static int _intel_hdcp_disable(struct intel_connector *connector)
>  
>  	I915_WRITE(PORT_HDCP_CONF(port), 0);
>  	if (intel_wait_for_register(dev_priv, PORT_HDCP_STATUS(port), ~0, 0,
> -				    20)) {
> +				    TIME_FOR_ENCRYPT_STATUS_CHANGE)) {
>  		DRM_ERROR("Failed to disable HDCP, timeout clearing status\n");
>  		return -ETIMEDOUT;
>  	}
> -- 
> 2.7.4
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Sean Paul, Software Engineer, Google / Chromium OS
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel