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From:   Jani Nikula <jani.nikula@linux.intel.com>
To:     Aurabindo Pillai <mail@aurabindo.in>,
        maarten.lankhorst@linux.intel.com, mripard@kernel.org,
        airlied@linux.ie, daniel@ffwll.ch
Cc:     linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org
Subject: Re: [PATCH] drm: dpcd: Print more useful information during error
In-Reply-To: <20200409195200.5483-1-mail@aurabindo.in>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
References: <20200409195200.5483-1-mail@aurabindo.in>
Date:   Tue, 14 Apr 2020 14:03:53 +0300
Message-ID: <87o8rumiqu.fsf@intel.com>
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Content-Type: text/plain
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On Thu, 09 Apr 2020, Aurabindo Pillai <mail@aurabindo.in> wrote:
> When DPCD access errors occur, knowing the register and request
> associated with the error helps debugging, so print the
> details in the debug message.
>
> Signed-off-by: Aurabindo Pillai <mail@aurabindo.in>
> ---
>  drivers/gpu/drm/drm_dp_helper.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
> index a5364b519..545606aac 100644
> --- a/drivers/gpu/drm/drm_dp_helper.c
> +++ b/drivers/gpu/drm/drm_dp_helper.c
> @@ -257,7 +257,9 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request,
>  			err = ret;
>  	}
>  
> -	DRM_DEBUG_KMS("Too many retries, giving up. First error: %d\n", err);
> +	DRM_DEBUG_KMS("dpcd: Too many retries, giving up. First error: %d\t"
> +		      "address: %x\trequest: %x\t size:%zu\n",
> +		      err, msg.address, msg.request, msg.size);

Nitpicks, please don't add tabs, maybe use commas instead, and please
add 0x in front of hex.

BR,
Jani.


>  	ret = err;
>  
>  unlock:

-- 
Jani Nikula, Intel Open Source Graphics Center