Message-ID: <fcdd9534-d494-3fdb-dfa7-1d15da6f697a@quicinc.com>
Date: Thu, 7 Aug 2025 16:36:41 +0530
From: Vikash Garodia <quic_vgarodia@...cinc.com>
To: Jorge Ramirez <jorge.ramirez@....qualcomm.com>,
        Konrad Dybcio
	<konrad.dybcio@....qualcomm.com>
CC: Dmitry Baryshkov <dmitry.baryshkov@....qualcomm.com>,
        <bryan.odonoghue@...aro.org>, <quic_dikshita@...cinc.com>,
        <konradybcio@...nel.org>, <krzk+dt@...nel.org>, <mchehab@...nel.org>,
        <conor+dt@...nel.org>, <andersson@...nel.org>,
        <linux-media@...r.kernel.org>, <linux-arm-msm@...r.kernel.org>,
        <devicetree@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v8 5/7] media: venus: core: Add qcm2290 DT compatible and
 resource data


On 8/6/2025 6:37 PM, Jorge Ramirez wrote:
> On 06/08/25 11:01:09, Konrad Dybcio wrote:
>> On 8/6/25 10:04 AM, Jorge Ramirez wrote:
>>> On 06/08/25 04:37:05, Dmitry Baryshkov wrote:
>>>> On Tue, Aug 05, 2025 at 01:27:34PM +0200, Jorge Ramirez wrote:
>>>>> On 05/08/25 12:44:23, Jorge Ramirez wrote:
>>>>>> On 05/08/25 13:04:50, Dmitry Baryshkov wrote:
>>>>>>> On Tue, Aug 05, 2025 at 08:44:28AM +0200, Jorge Ramirez-Ortiz wrote:
>>>>>>>> Add a qcm2290 compatible binding to the Cenus core.
>>>>>>>>
>>>>>>>> The maximum concurrency is video decode at 1920x1080 (FullHD) with video
>>>>>>>> encode at 1280x720 (HD).
>>>>>>>>
>>>>>>>> The driver is not available to firmware versions below 6.0.55 due to an
>>>>>>>> internal requirement for secure buffers.
>>>>>>>>
>>>>>>>> The bandwidth tables incorporate a conservative safety margin to ensure
>>>>>>>> stability under peak DDR and interconnect load conditions.
>>>>>>>>
>>>>>>>> Co-developed-by: Loic Poulain <loic.poulain@....qualcomm.com>
>>>>>>>> Signed-off-by: Loic Poulain <loic.poulain@....qualcomm.com>
>>>>>>>> Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez@....qualcomm.com>
>>>>>>>> Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@...aro.org>
>>>>>>>> Reviewed-by: Dikshita Agarwal <quic_dikshita@...cinc.com>
>>>>>>>> ---
>>>>>>>>  drivers/media/platform/qcom/venus/core.c | 50 ++++++++++++++++++++++++
>>>>>>>>  1 file changed, 50 insertions(+)
>>>>>>>>
>>>>>>>> diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c
>>>>>>>> index adc38fbc9d79..753a16f53622 100644
>>>>>>>> --- a/drivers/media/platform/qcom/venus/core.c
>>>>>>>> +++ b/drivers/media/platform/qcom/venus/core.c
>>>>>>>> @@ -1070,6 +1070,55 @@ static const struct venus_resources sc7280_res = {
>>>>>>>>  	.enc_nodename = "video-encoder",
>>>>>>>>  };
>>>>>>>>  
>>>>>>>> +static const struct bw_tbl qcm2290_bw_table_dec[] = {
>>>>>>>> +	{ 352800, 597000, 0, 746000, 0 }, /* 1080p@30 + 720p@30 */
>>>>>>>> +	{ 244800, 413000, 0, 516000, 0 }, /* 1080p@30 */
>>>>>>>> +	{ 216000, 364000, 0, 454000, 0 }, /* 720p@60  */
>>>>>>>> +	{ 108000, 182000, 0, 227000, 0 }, /* 720p@30  */
>>>>>>>> +};
>>>>>>>> +
>>>>>>>> +static const struct bw_tbl qcm2290_bw_table_enc[] = {
>>>>>>>> +	{ 352800, 396000, 0, 0, 0 }, /* 1080p@30 + 720p@30 */
>>>>>>>> +	{ 244800, 275000, 0, 0, 0 }, /* 1080p@30 */
>>>>>>>> +	{ 216000, 242000, 0, 0, 0 }, /* 720p@60  */
>>>>>>>> +	{ 108000, 121000, 0, 0, 0 }, /* 720p@30  */
>>>>>>>> +};
>>>>>>>> +
>>>>>>>> +static const struct firmware_version min_fw = {
>>>>>>>> +	.major = 6, .minor = 0, .rev = 55,
>>>>>>>> +};
>>>>>>>
>>>>>>> This will make venus driver error out with the firmware which is
>>>>>>> available in Debian trixie (and possibly other distributions). If I
>>>>>>> remember correctly, the driver can work with that firmware with the
>>>>>>> limited functionality. Can we please support that instead of erroring
>>>>>>> out completely?
>>>>>>
>>>>>> yes, in V7 I did implement this functionality plus a fix for EOS
>>>>>> handling (broken in pre 6.0.55 firmwares).
>>>>>
>>>>> just re-reading your note, in case this was not clear, the _current_
>>>>> driver upstream will never work with the current firmware if that is
>>>>> what you were thinking (it would need v7 of this series to enable video
>>>>> decoding).
>>>>
>>>> I'd really prefer if we could support firmware that is present in Debian
>>>> trixie and that has been upstreamed more than a year ago.
>>>
>>>
>>> I share your view — which is why I put the effort into v7 — but I also
>>> understand that maintaining the extra code and EOS workaround for
>>> decoding needs to be justifiable. So I chose to align with the
>>> maintainers' perspective on this and removed it on v8 (partially also
>>> because I wanted to unblock the current EOS discussion).
>>
>> +$0.05
>>
>> I thought we were going to eventually relax/drop the fw requirement
>> when the driver learns some new cool tricks, but are we now straying
>> away from that? (particularly thinking about the EOS part)
>>
> 
> um, no not really: the decision was to simply drop support for pre
> 6.0.55 firmwares for the AR50_LITE.
> 
> Pre 6.0.55:
> 
> -  has a requirement for secure buffers to support encoding
> -  requires a driver workaround for EOS (providing a dummy length)
> -  during video encoding.
> 
> To support < 6.0.55, v7 of the driver patchset:
> 
> - uses the version to disable the encode node
> - enables the video decode node
> - implements the EOS workaround.
> 
> It was agreed that this complexity was not necessary and that we should
> just drop <6.0.55 firmware support (which would in any case only include
> video decode).
> 
> And so on v8, I removed the above.
> 
> Now I have v9 ready to post it, but Dmitry is asking why cant we have
> the v7 functionality so I am waiting for direction.

the issue is in firmware for both encoder and decoder. Didn't like the idea of
driver carrying the hack for a firmware issue. Just because, for encoder, we are
unable to hack it in driver, we are ok to have it enabled in a newer version of
the firmware, we can follow the same for decoders as well.

Regards,
Vikash

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