Re: [RFC PATCH] soc: imx: Try harder to get imq8mq SoC revisions

From: Leonard Crestez
Date: Wed May 22 2019 - 09:33:38 EST


On 22.05.2019 16:13, Guido Günther wrote:
> Subject: Re: [RFC PATCH] soc: imx: Try harder to get imq8mq SoC revisions

Fixed subject

> On Wed, May 08, 2019 at 02:40:18PM +0200, Guido Günther wrote:
>> Thanks for your comments. Let's try s.th. different then: identify by
>> bootrom, ocotop and anatop and fall back to ATF afterwards (I'll split
>> out the DT part and add binding docs if this makes sense). I'm also
>> happy to drop the whole ATF logic until mailine ATF catched up:
>>
>> The mainline ATF doesn't currently support the FSL_SIP_GET_SOC_INFO call
>> nor does it have the code to identify different imx8mq SOC revisions so
>> mimic what NXPs ATF does here.
>
> Does this makes sense? If so I'll send this out as a series.

Mainline ATF has recently caught up:

https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/plat/imx/imx8m/imx8mq/imx8mq_bl31_setup.c#n52

>> As a fallback use ATF so we can identify new revisions once it gains
>> support or when using NXPs ATF.
>
> I'm also fine with dropping the ATF part if we don't want to depend on
> it in mainline.

Linux arm64 depends on ATF to implement power management via PSCI:
hotplug cpuidle and suspend.

It is not clear why Linux would avoid other services and insist on
reimplementing hardware workarounds.

--
Regards,
Leonard