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Message-ID: <9acc7001-2b3a-f635-9814-95850a71f142@linaro.org>
Date:   Fri, 5 May 2023 21:24:12 +0200
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Subject: Re: [PATCH v2 06/18] media: venus: firmware: Leave a clue for
 homegrown porters
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To:     Vikash Garodia <quic_vgarodia@quicinc.com>,
        Stanimir Varbanov <stanimir.k.varbanov@gmail.com>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Dikshita Agarwal <dikshita@qti.qualcomm.com>,
        Bryan O'Donoghue <bryan.odonoghue@linaro.org>,
        Mansur Alisha Shaik <mansur@codeaurora.org>,
        Jonathan Marek <jonathan@marek.ca>,
        Hans Verkuil <hans.verkuil@cisco.com>,
        Dikshita Agarwal <quic_dikshita@quicinc.com>
Cc:     Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
        Stanimir Varbanov <stanimir.varbanov@linaro.org>,
        linux-media@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Marijn Suijten <marijn.suijten@somainline.org>
References: <20230228-topic-venus-v2-0-d95d14949c79@linaro.org>
 <20230228-topic-venus-v2-6-d95d14949c79@linaro.org>
 <ef50ac6c-a635-7f83-c484-a4f91b5e5d12@quicinc.com>
 <579f3480-1cbc-5688-7226-986205b5825e@quicinc.com>
From:   Konrad Dybcio <konrad.dybcio@linaro.org>
In-Reply-To: <579f3480-1cbc-5688-7226-986205b5825e@quicinc.com>
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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?

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,
>>>