Re: [PATCH v3 12/15] drm/bridge: Add ITE IT6263 LVDS to HDMI converter
From: Liu Ying
Date: Fri Oct 25 2024 - 04:24:45 EST
On 10/24/2024, Biju Das wrote:
> Hi Liu Ying,
Hi Biju,
>
>> -----Original Message-----
>> From: Liu Ying <victor.liu@xxxxxxx>
>> Sent: Monday, October 21, 2024 7:45 AM
>> Subject: [PATCH v3 12/15] drm/bridge: Add ITE IT6263 LVDS to HDMI converter
>>
>> Add basic HDMI video output support. Currently, only RGB888 output pixel format is supported. At the
>> LVDS input side, the driver supports single LVDS link and dual LVDS links with "jeida-24" LVDS
>> mapping.
>>
>> Product link:
>> https://www.ite.com.tw/en/product/cate1/IT6263
>
> Just a question,
>
> What is the maximum single link and dual link modes you have tested?
With single LVDS link on i.MX8MP EVK, the highest pixel clock rate I
tested is 74.25MHz(1280x720@60). i.MX8MP LVDS Display Bridge(LDB)
supports the highest 80MHz pixel clock rate with single LVDS link.
With single LVDS link on i.MX8qxp MEK, the highest pixel clock rate I
tested is 148.5MHz(1920x1080@60). i.MX8qxp LDB supports the highest
150MHz pixel clock rate with single LVDS link.
With dual LVDS links on both i.MX8MP EVK and i.MX8qxp MEK, the highest
pixel clock rate I tested is 148.5MHz(1920x1080@60).
>
> On Renesas SMARC RZ/G3E platform I have tested with this patch set,
>
> Dual link :1080p@60
>
> and
>
> Single link:720p@60
>
> For single link > 720p@60, sometimes I get message
> "it6263 7-004c: failed to wait for video stable"
I don't see this with i.MX8MP EVK and i.MX8qxp MEK.
>
> From SoC side, it can support max dot clock of 87MHz for single link.
>
> So just wondering other than reject modes greater than 87MHz from SOC
> side, do we need to limit any thing on bridge device for single link Case?
Since IT6263 works with 1920x1080@60(148.5MHz pixel clock rate) on
i.MX8qxp MEK by using single LVDS link, I'm currently fine with
the existing clock rate validation against the maximal 150MHz pixel
clock rate.
>
> Cheers,
> Biju
--
Regards,
Liu Ying