Re: [PATCH v2 06/18] media: venus: firmware: Leave a clue for homegrown porters

[Vikash Garodia <quic_vgarodia@quicinc.com>]

On 5/6/2023 12:54 AM, Konrad Dybcio wrote:
> 
> 
> On 5.05.2023 15:00, Vikash Garodia wrote:
>>
>> On 5/5/2023 6:27 PM, Vikash Garodia wrote:
>>>
>>> On 5/4/2023 1:31 PM, Konrad Dybcio wrote:
>>>> Leave a clue about where the seemingly magic values come from, as it
>>>> is not obvious and requires some digging downstream..
>> Rephrase the commit text.
> Please be more specific, do you want me to use the
> explanations you gave in the previous reply?

Something which describes the patch like - Add comments to describe the
arguments of the qcom_scm_mem_protect_video_var TZ call. The TZ call programs
the video hardware with CP and non-CP VARs, and the comments describes these VARs.

> Konrad
>>>> Reviewed-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
>>>> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
>>> Reviewed-by: Vikash Garodia <quic_vgarodia@quicinc.com>
>>>> ---
>>>>   drivers/media/platform/qcom/venus/firmware.c | 7 +++++++
>>>>   1 file changed, 7 insertions(+)
>>>>
>>>> diff --git a/drivers/media/platform/qcom/venus/firmware.c b/drivers/media/platform/qcom/venus/firmware.c
>>>> index cfb11c551167..a4cd919e1dbe 100644
>>>> --- a/drivers/media/platform/qcom/venus/firmware.c
>>>> +++ b/drivers/media/platform/qcom/venus/firmware.c
>>>> @@ -241,6 +241,13 @@ int venus_boot(struct venus_core *core)
>>>>           return ret;
>>>>         if (core->use_tz && res->cp_size) {
>>>> +        /*
>>>> +         * Clues for porting using downstream data:
>>>> +         * cp_start = 0
>>>> +         * cp_size = venus_ns/virtual-addr-pool[0] (yes, addr not size)
>>>
>>> The field is the start address of ns context bank. Since the cp_start is 0, the start address for (next) non-secure context bank
>>>
>>> is interpreted as size of the (previous) content protection region.
>>>
>>>> +         * cp_nonpixel_start = venus_sec_non_pixel/virtual-addr-pool[0]
>>>> +         * cp_nonpixel_size = venus_sec_non_pixel/virtual-addr-pool[1]
>>>> +         */
>>>>           ret = qcom_scm_mem_protect_video_var(res->cp_start,
>>>>                                res->cp_size,
>>>>                                res->cp_nonpixel_start,
>>>>