Re: [PATCH v4 1/3] xen/arm: Add imx8q{m,x} platform glue

[John Ernberg <john.ernberg@xxxxxxxx>]

On 4/9/24 8:47 AM, Michal Orzel wrote:
> Hi John,
> 
> On 08/04/2024 18:11, John Ernberg wrote:
>>
>>
>> When using Linux for dom0 there are a bunch of drivers that need to do SMC
>> SIP calls into the firmware to enable certain hardware bits like the
>> watchdog.
>>
>> Provide a basic platform glue that implements the needed SMC forwarding.
>>
>> The format of these calls are as follows:
>>   - reg 0: function ID
>>   - reg 1: subfunction ID (when there's a subfunction)
>>   remaining regs: args
>>
>> For now we only allow Dom0 to make these calls as they are all managing
>> hardware. There is no specification for these SIP calls, the IDs and names
>> have been extracted from the upstream linux kernel and the vendor kernel.
>>
>> Most of the SIP calls are only available for the iMX8M series of SoCs, so
>> they are easy to reject and they need to be revisited when iMX8M series
>> support is added.
> Stale paragraph. Should be removed given that the driver targets only Q{M,XP}.
> 
>>
>>  From the other calls we can reject CPUFREQ because Dom0 cannot make an
>> informed decision regarding CPU frequency scaling, WAKEUP_SRC is to wake
>> up from suspend, which Xen doesn't support at this time.
>>
>> This leaves the TIME SIP, OTP SIPs, BUILDINFO SIP and TEMP ALARM SIP, which
>> for now are allowed to Dom0.
> BUILDINFO, TEMP ALARM are leftovers from previous revision.
> 
>>
>> NOTE: This code is based on code found in NXP Xen tree located here:
>> https://github.com/nxp-imx/imx-xen/blob/lf-5.10.y_4.13/xen/arch/arm/platforms/imx8qm.c
>>
>> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
>> [jernberg: Add SIP call filtering]
>> Signed-off-by: John Ernberg <john.ernberg@xxxxxxxx>
> Reviewed-by: Michal Orzel <michal.orzel@xxxxxxx>
> 
> The commit msg can be fixed on commit.
> 
> ~Michal


Apologies for forgetting to adjust that. Let me know if it's easier for 
you if I do a v5 with the fixed commit message.

Thanks! // John Ernberg