Re: [PATCH v11 03/19] drm: bridge: analogix/dp: remove duplicate configuration of link rate and link count

From: "Jingoo Han" <jingoohan1@gmail.com>
To: "'Yakir Yang'" <ykk@rock-chips.com>,
	"'Inki Dae'" <inki.dae@samsung.com>,
	"'Mark Yao'" <mark.yao@rock-chips.com>,
	"'Heiko Stuebner'" <heiko@sntech.de>
Cc: "'Thierry Reding'" <treding@nvidia.com>,
	"'Krzysztof Kozlowski'" <k.kozlowski@samsung.com>,
	"'Rob Herring'" <robh+dt@kernel.org>,
	"'Russell King'" <linux@arm.linux.org.uk>,
	<emil.l.velikov@gmail.com>,
	"'Gustavo Padovan'" <gustavo.padovan@collabora.co.uk>,
	"'Kishon Vijay Abraham I'" <kishon@ti.com>,
	<javier@osg.samsung.com>, "'Andy Yan'" <andy.yan@rock-chips.com>,
	<dri-devel@lists.freedesktop.org>, <devicetree@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>,
	<linux-samsung-soc@vger.kernel.org>,
	<linux-rockchip@lists.infradead.org>,
	<linux-arm-kernel@lists.infradead.org>,
	"'Jingoo Han'" <jingoohan1@gmail.com>
Subject: Re: [PATCH v11 03/19] drm: bridge: analogix/dp: remove duplicate configuration of link rate and link count
Date: Tue, 22 Dec 2015 21:09:33 +0900	[thread overview]
Message-ID: <000701d13cb1$a3d5f0c0$eb81d240$@com> (raw)
In-Reply-To: <1450236502-1713-1-git-send-email-ykk@rock-chips.com>

On Wednesday, December 16, 2015 12:28 PM, Yakir Yang wrote:
> 
> link_rate and lane_count already configured in analogix_dp_set_link_train(),
> so we don't need to config those repeatly after training finished, just
> remove them out.
> 
> Beside Display Port 1.2 already support 5.4Gbps link rate, the maximum sets
> would change from {1.62Gbps, 2.7Gbps} to {1.62Gbps, 2.7Gbps, 5.4Gbps}.
> 
> Signed-off-by: Yakir Yang <ykk@rock-chips.com>
> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
> ---
> Changes in v11: None
> Changes in v10: None
> Changes in v9: None
> Changes in v8: None
> Changes in v7: None
> Changes in v6: None
> Changes in v5: None
> Changes in v4:
> - Update commit message more readable. (Jingoo)
> - Adjust the order from 05 to 04
> 
> Changes in v3:
> - The link_rate and lane_count shouldn't config to the DT property value
>   directly, but we can take those as hardware limite. For example, RK3288
>   only support 4 physical lanes of 2.7/1.62 Gbps/lane, so DT property would
>   like "link-rate = 0x0a" "lane-count = 4". (Thierry)
> 
> Changes in v2: None
> 
>  drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 8 ++++----
>  drivers/gpu/drm/bridge/analogix/analogix_dp_core.h | 5 +++--
>  2 files changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> index 4a05c2b..6f899cd 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> @@ -624,6 +624,8 @@ static void analogix_dp_get_max_rx_bandwidth(struct analogix_dp_device *dp,
>  	/*
>  	 * For DP rev.1.1, Maximum link rate of Main Link lanes
>  	 * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps
> +	 * For DP rev.1.2, Maximum link rate of Main Link lanes
> +	 * 0x06 = 1.62 Gbps, 0x0a = 2.7 Gbps, 0x14 = 5.4Gbps
>  	 */
>  	analogix_dp_read_byte_from_dpcd(dp, DP_MAX_LINK_RATE, &data);
>  	*bandwidth = data;
> @@ -657,7 +659,8 @@ static void analogix_dp_init_training(struct analogix_dp_device *dp,
>  	analogix_dp_get_max_rx_lane_count(dp, &dp->link_train.lane_count);
> 
>  	if ((dp->link_train.link_rate != LINK_RATE_1_62GBPS) &&
> -	    (dp->link_train.link_rate != LINK_RATE_2_70GBPS)) {
> +	    (dp->link_train.link_rate != LINK_RATE_2_70GBPS) &&
> +	    (dp->link_train.link_rate != LINK_RATE_5_40GBPS)) {
>  		dev_err(dp->dev, "Rx Max Link Rate is abnormal :%x !\n",
>  			dp->link_train.link_rate);
>  		dp->link_train.link_rate = LINK_RATE_1_62GBPS;
> @@ -898,9 +901,6 @@ static void analogix_dp_commit(struct analogix_dp_device *dp)
>  	analogix_dp_enable_rx_to_enhanced_mode(dp, 1);
>  	analogix_dp_enable_enhanced_mode(dp, 1);
> 
> -	analogix_dp_set_lane_count(dp, dp->video_info->lane_count);
> -	analogix_dp_set_link_bandwidth(dp, dp->video_info->link_rate);
> -
>  	analogix_dp_init_video(dp);
>  	ret = analogix_dp_config_video(dp);
>  	if (ret)
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> index 8e84208..57aa4b0d 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> @@ -21,8 +21,9 @@
>  #define MAX_EQ_LOOP			5
> 
>  enum link_rate_type {
> -	LINK_RATE_1_62GBPS = 0x06,
> -	LINK_RATE_2_70GBPS = 0x0a
> +	LINK_RATE_1_62GBPS = DP_LINK_BW_1_62,
> +	LINK_RATE_2_70GBPS = DP_LINK_BW_2_7,
> +	LINK_RATE_5_40GBPS = DP_LINK_BW_5_4,

Then, how about removing 'enum link_rate_type'?
If DP_LINK_BW_* are used, LINK_RATE_* are not necessary.

Best regards,
Jingoo Han

>  };
> 
>  enum link_lane_count_type {
> --
> 1.9.1