Re: [PATCH 6/6] ARM: da850: adjust memory settings for tilcdc
From: Bartosz Golaszewski
Date: Fri Sep 30 2016 - 05:31:58 EST
2016-09-29 21:07 GMT+02:00 Karl Beldan <karl.beldan@xxxxxxxxx>:
> Hi,
>
> On Thu, Sep 29, 2016 at 06:31:55PM +0200, Bartosz Golaszewski wrote:
>> Default memory settings of da850 do not meet the throughput/latency
>> requirements of tilcdc. This results in the image displayed being
>> incorrect and the following warning being displayed by the LCDC
>> drm driver:
>>
>> tilcdc da8xx_lcdc.0: tilcdc_crtc_irq(0x00000020): FIFO underfow
>>
>> Reconfigure the LCDC priority to the highest. This is a workaround
>> for the da850-lcdk board which has the LCD controller enabled in
>> the device tree, but a long-term, system-wide fix is needed for
>> all davinci boards.
>>
>> This patch has been modified for mainline linux. It comes from a
>> downstream TI release for da850[1].
>>
>> Original author: Vishwanathrao Badarkhe, Manish <manishv.b@xxxxxx>
>>
>> [1] http://arago-project.org/git/projects/linux-davinci.git?p=projects/linux-davinci.git;a=commitdiff;h=b9bd39a34cc02c3ba2fc15539a2f0bc2b68d25da;hp=6f6c795faa6366a4ebc1037a0235edba6018a991
>>
>> Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
>> ---
>
> FWIW, the quirks could be applied conditionnally depending on the lcdc
> node presence in the DT, a bit like:
> https://github.com/kbeldan/linux/commit/cf15572ffef8e8a0d8110b3f6b29bd401d0538be
> https://github.com/kbeldan/linux/commit/07e4fff9958bc1625a96791dce284c163fbe9c43
>
>
> Regards,
> Karl
Hi Karl,
I decided to post the simplest possible way of this to get the lcdc
working upstream. In parallel I'm working on a system-wide way of
applying such quirks not only limited to device tree nodes' presence.
Thanks for the info!
Best regards,
Bartosz Golaszewski