[PATCH 13/16] arm: rmobile: Add CPU detection for RZ/G2L

[Marek Vasut]

On 10/4/23 11:05, Paul Barker wrote:
> On 03/10/2023 14:28, Marek Vasut wrote:
>> On 9/20/23 14:42, Paul Barker wrote:
>>> The ARM TrustedFirmware code for the Renesas RZ/G2L SoC family passes a
>>> devicetree blob to the bootloader as an argument in the same was
>>
>> same way (typo)
>>
>>> previous R-Car gen3/gen4 SoCs.
>>
>> Gen3 / Gen4
>>
>>> This blob contains a compatible string
>>> which can be used to identify the particular SoC we are running on.
>>
>> Why not read the PRR ?
> 
> Reading the DEVID & PRR registers is not sufficient to tell the SoCs apart.
> 
>  From page 204 of the datasheet (R01UH0914EJ0130 Rev.1.30) regarding the
> DEVID register:
> 
> "Note: RZ/G2L and RZ/G2LC are the same value.
> If identification between G2L and G2LC is needed, read the value of
> address H’0_1186_1178.
> The value is below.
> H’0000_0000: RZ/G2L
> H’0000_0001: RZ/G2LC"
> 
> Address 0x11861178 is in the OTP region which can only be read from the
> secure world (i.e. TrustedFirmware). So we have to rely on
> TrustedFirmware to determine the SoC and pass this information to u-boot
> via an fdt blob.

This ^ really should go into the commit message :)