[PATCH 3/3] imx: power-domain: Get rid of SMCCC dependency

[Marek Vasut]

On 4/16/22 22:49, Adam Ford wrote:
> On Thu, Apr 7, 2022 at 5:21 PM Tim Harvey <tharvey at gateworks.com> wrote:
>>
>> On Wed, Mar 30, 2022 at 8:04 PM Marek Vasut <marex at denx.de> wrote:
>>>
>>> This driver is the only SMCCC dependency in iMX8M U-Boot port. Rework
>>> the driver based on Linux GPCv2 driver to directly control the GPCv2
>>> block instead of using SMCCC calls. This way, U-Boot can operate the
>>> i.MX8M power domains without depending on anything else.
>>>
>>> This is losely based on Linux GPCv2 driver. The GPU, VPU, MIPI power
>>> domains are not supported to save space, since they are not useful in
>>> the bootloader. The only domains kept are ones for HSIO, PCIe, USB.
>>>
>>> Signed-off-by: Marek Vasut <marex at denx.de>
>>> Cc: Fabio Estevam <festevam at gmail.com>
>>> Cc: Peng Fan <peng.fan at nxp.com>
>>> Cc: Stefano Babic <sbabic at denx.de>
>>> ---
>>> NOTE: So far this is tested on MX8MM and MX8MN. MX8MQ is not tested.
> 
> Sorry for the delay, I tested positive for Covid and needed to recover a bit.
> 
> I have confirmed this makes the 8MQ hang during boot.
> 
> Before patch series:
> 
> U-Boot SPL 2022.04-00812-g9859465bfe (Apr 16 2022 - 15:41:46 -0500)
> PMIC:  PFUZE100 ID=0x10
> SEC0:  RNG instantiated
> Normal Boot
> Trying to boot from MMC2
> 
> 
> U-Boot 2022.04-00812-g9859465bfe (Apr 16 2022 - 15:41:46 -0500)
> 
> CPU:   Freescale i.MX8MQ rev2.1 at 1000 MHz
> Reset cause: POR
> Model: NXP i.MX8MQ EVK
> DRAM:  3 GiB
> Core:  59 devices, 16 uclasses, devicetree: separate
> MMC:   FSL_SDHC: 0, FSL_SDHC: 1
> Loading Environment from MMC... *** Warning - bad CRC, using default environment
> 
> In:    serial
> Out:   serial
> Err:   serial
> SEC0:  RNG instantiated
> Net:   eth0: ethernet at 30be0000
> Hit any key to stop autoboot:  0
> u-boot=>
> 
> After the patch:
> 
> U-Boot SPL 2022.04-00822-gc2a24a7ce5 (Apr 16 2022 - 15:45:29 -0500)
> PMIC:  PFUZE100 ID=0x10
> SEC0:  RNG instantiated
> Normal Boot
> Trying to boot from MMC2

There should be some sort of output from ATF here, which version did you 
use during your tests ?

Did you set IMX_BOOT_UART_BASE correctly ?

Did you set ATF_LOAD_ADDR correctly ?

Do you get a hang when you revert only this specific patch ?

The GPC is only used for USB and PCI on the MX8MQ, so you shouldn't be 
getting hang so early as to get no output at all.

> <hang>
> 
> I can test it on 8MN and 8MM, but it sounds like that's already been done.

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