Re: [PATCH v2 1/8] drm/bridge: dw-hdmi: Add SCDC and TMDS Scrambling support

[Neil Armstrong]

Hi Rob,

Le 14/03/2019 19:55, Rob Herring a Ãcrit :
> On Mon, Mar 11, 2019 at 3:53 AM Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>>
>> On 08/03/2019 15:54, Rob Herring wrote:
>>> On Fri, Mar 8, 2019 at 2:05 AM Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>>>>
>>>> Hi Rob,
>>>>
>>>> On 08/03/2019 00:13, Rob Herring wrote:
>>>>> On Fri, Feb 1, 2019 at 6:08 AM Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>>>>>>
>>>>>> Add support for SCDC Setup for TMDS Clock > 3.4GHz and enable TMDS
>>>>>> Scrambling when supported or mandatory.
>>>>>>
>>>>>> This patch also adds an helper to setup the control bit to support
>>>>>> the high TMDS Bit Period/TMDS Clock-Period Ratio as required with
>>>>>> TMDS Clock > 3.4GHz for HDMI2.0 3840x2160@60/50 modes.
>>>>>>
>>>>>> These changes were based on work done by Huicong Xu <xhc@xxxxxxxxxxxxxx>
>>>>>> and Nickey Yang <nickey.yang@xxxxxxxxxxxxxx> to support HDMI2.0 modes
>>>>>> on the Rockchip 4.4 BSP kernel at [1]
>>>>>>
>>>>>> [1] https://github.com/rockchip-linux/kernel/tree/release-4.4
>>>>>>
>>>>>> Cc: Nickey Yang <nickey.yang@xxxxxxxxxxxxxx>
>>>>>> Cc: Huicong Xu <xhc@xxxxxxxxxxxxxx>
>>>>>> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
>>>>>> Tested-by: Heiko Stuebner <heiko@xxxxxxxxx>
>>>>>> Reviewed-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>
>>>>>> ---
>>>>>>  drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 85 ++++++++++++++++++++++++++++++-
>>>>>>  drivers/gpu/drm/bridge/synopsys/dw-hdmi.h |  1 +
>>>>>>  include/drm/bridge/dw_hdmi.h              |  1 +
>>>>>>  3 files changed, 85 insertions(+), 2 deletions(-)
>>>>>
>>>>> This commit in drm-misc-next is breaking booting on the Rock960. I
>>>>> have FB and fbcon enabled. The boot hangs after this message:
>>>>>
>>>>> [    3.012334] [drm:rockchip_drm_fbdev_create] FB [1920x1080]-24
>>>>> kvaddr=(____ptrval____) offset=0 size=8294400
>>>>
>>>> Could you give more details on the tree used ? did you bisect to find this commit ?
>>>
>>> As I said above, drm-misc-next (from drm-misc tree) is the branch. I
>>> bisected between it and v5.0. Reverting it fixes booting.
>>
>> Thanks, could you give more details on the environment ? Did you test over the latest linux-next ?
> 
> Here's a log of the drm parts: https://pastebin.com/tFJ9Gs6h
> 
> linux-next also hangs.
> 
>> Can you share the EDID of your monitor ?
> 
> Maybe not mode related. I tried forcing to 1280x720 and it hangs too.
> In any case, here's the parsed EDID:
> 
> 256-byte EDID successfully retrieved from i2c bus 3
> Looks like i2c was successful. Have a good day.
> Checksum Correct
> 
> Section "Monitor"
> Identifier "CYS-R101"
> ModelName "CYS-R101"
> VendorName "CYX"
> # Monitor Manufactured week 28 of 2018
> # EDID version 1.3
> # Digital Display
> DisplaySize 220 130
> Gamma 2.20
> Option "DPMS" "true"
> Horizsync 30-102
> VertRefresh 48-75
> # Maximum pixel clock is 190MHz
> #Not giving standard mode: 1920x1080, 60Hz
> #Not giving standard mode: 1920x1080, 60Hz
> #Not giving standard mode: 1920x1080, 60Hz
> #Not giving standard mode: 1440x900, 60Hz
> #Not giving standard mode: 1400x1050, 60Hz
> #Not giving standard mode: 1280x1024, 60Hz
> #Not giving standard mode: 1280x960, 60Hz
> #Not giving standard mode: 1280x720, 60Hz
> 
> #Extension block found. Parsing...
> Modeline "Mode 5" 54.00 2560 2608 2640 2720 1440 1443 1448 1481 +hsync +vsync
> Modeline "Mode 0" 267.81 2560 2608 2640 2720 1600 1603 1608 1641 +hsync +vsync
> Modeline "Mode 1" 148.500 1920 2008 2052 2200 1080 1084 1089 1125 +hsync +vsync
> Modeline "Mode 2" 74.250 1920 2008 2052 2200 1080 1082 1087 1125
> +hsync +vsync interlace
> Modeline "Mode 3" 74.250 1280 1390 1420 1650 720 725 730 750 +hsync +vsync
> Modeline "Mode 4" 148.500 1920 2448 2492 2640 1080 1084 1089 1125 +hsync +vsync
> Option "PreferredMode" "Mode 5"
> EndSection
> 
>> Can you check this patch :
> 
> Still hangs with it.


Thanks for testing, the only impact would be if hdmi_info->scdc.supported
and hdmi_info->scdc.scrambling.low_rate were true.
Honestly, hdmi_info->scdc.scrambling.low_rate wasn't really tested.

Could you dump the edid in binary format ? or parse it with https://github.com/rpavlik/edid-decode
supporting modern HDMI EDIDs.


Thanks,
Neil
> 
>>
>> ----><----------------------------------------------------------------------------------------
>> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
>> index a63e5f0dae56..f33c2ac158c1 100644
>> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
>> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
>> @@ -1268,8 +1268,6 @@ static int hdmi_phy_configure(struct dw_hdmi *hdmi)
>>
>>         dw_hdmi_phy_power_off(hdmi);
>>
>> -       dw_hdmi_set_high_tmds_clock_ratio(hdmi);
>> -
>>         /* Leave low power consumption mode by asserting SVSRET. */
>>         if (phy->has_svsret)
>>                 dw_hdmi_phy_enable_svsret(hdmi, 1);
>>
>>