Re: [PATCH v5 2/2] firmware: arm_scmi: Add qcom smc/hvc transport support

Nikunj Kela
2023-10-09T17:49:58Z

On 10/9/2023 8:29 AM, Sudeep Holla wrote:
> On Mon, Oct 09, 2023 at 07:59:08AM -0700, Nikunj Kela wrote:
>> On 10/9/2023 7:47 AM, Sudeep Holla wrote:
>>> On Fri, Oct 06, 2023 at 09:42:06AM -0700, Nikunj Kela wrote:
>>>> This change adds the support for SCMI message exchange on Qualcomm
>>>> virtual platforms.
>>>>
>>>> The hypervisor associates an object-id also known as capability-id
>>>> with each smc/hvc doorbell object. The capability-id is used to
>>>> identify the doorbell from the VM's capability namespace, similar
>>>> to a file-descriptor.
>>>>
>>>> The hypervisor, in addition to the function-id, expects the capability-id
>>>> to be passed in x1 register when SMC/HVC call is invoked.
>>>>
>>>> The capability-id is allocated by the hypervisor on bootup and is stored in
>>>> the shmem region by the firmware before starting Linux.
>>>>
>>> Since you are happy to move to signed value, I assume you are happy to loose
>>> upper half of the range values ?
>>>
>>> Anyways after Bjorn pointed out inconsistency, I am thinking of moving
>>> all the values to unsigned long to work with both 32bit and 64bit.
>>>
>>> Does the below delta on top of this patch works for you and makes sense?
>> This looks good to me. Will do some testing and float v6 with the changes
>> you suggested below. Thanks
>>
> Please refer or use the patch from [1] when reposting. I rebased on my
> patch[2] that I posted few minutes back. I am trying to finalise the branch
> and send PR in next couple of days, so please test and post sooner. Sorry
> for the rush.

Validated the patch from [1] below on Qualcomm ARM64 virtual platform
using SMC64 convention. Thanks!

>
> --
> Regards,
> Sudeep
> [1] https://git.kernel.org/sudeep.holla/h/for-next/scmi/updates
> [2] https://lore.kernel.org/r/20231009152049.1428872-1-sudeep.holla@arm.com