Re: [PATCH 2/2] media: iris: Enable Gen2 HFI on SC7280

[Bryan O'Donoghue <bod@kernel.org>]

On 12/02/2026 13:05, Dikshita Agarwal wrote:
> 
> 
> On 2/12/2026 5:13 PM, Konrad Dybcio wrote:
>> On 2/12/26 12:16 PM, Dikshita Agarwal wrote:
>>>
>>>
>>> On 2/9/2026 6:05 PM, Dmitry Baryshkov wrote:
>>>> On Mon, Feb 09, 2026 at 05:04:48PM +0530, Dikshita Agarwal wrote:
>>>>>
>>>>>
>>>>> On 2/9/2026 3:32 PM, Konrad Dybcio wrote:
>>>>>> On 2/9/26 10:45 AM, Dikshita Agarwal wrote:
>>>>>>> SC7280 supports both Gen1 and Gen2 HFI firmware. The driver continues to
>>>>>>> use Gen1 by default, but boards that intend to use Gen2 firmware can
>>>>>>> opt‑in by specifying a Gen2 image through the Device Tree
>>>>>>> 'firmware-name' property.
>>>>>>>
>>>>>>> Based on this property and the availability of the referenced
>>>>>>> firmware binary, the driver selects the appropriate HFI generation and
>>>>>>> updates its platform data accordingly. Boards that do not
>>>>>>> specify a Gen2 firmware, or where the firmware is not present,
>>>>>>> automatically fall back to Gen1.
>>>>>>>
>>>>>>> Signed-off-by: Dikshita Agarwal <dikshita.agarwal@oss.qualcomm.com>
>>>>>>> ---
>>
>> [...]
>>
>>>>> To avoid accidental matches, I can switch to an exact filename match
>>>>> instead. That way, only the specific Gen2 image (for example
>>>>> "qcom/vpu/vpu20_p1_gen2.mbn") will trigger the Gen2 path, and boards that
>>>>
>>>> How do you detect that for the OEM-signed firmware, which can have
>>>> random name?
>>>>
>>>>> want to use Gen2 can opt in by naming the firmware accordingly.
>>>
>>> I Explored on suggested alternative approaches and seeing some limitation
>>> with the both of them:
>>>
>>> 1. Detecting Gen1/Gen2 by scanning the firmware blob (fw->data)
>>> It is possible to parse QC_IMAGE_VERSION_STRING from the .mbn and  extract
>>> the version string. The issues with this approach :
>>>
>>> - the version string has no explicit marker that identifies Gen1 vs Gen2.
>>>
>>> - This prefix is not a formal ABI, and it is not consistent across SoCs.
>>> Each SoC family uses different naming patterns in the version string.
>>>
>>> Example : For SC7280 Gen1 we currently see:
>>> QC_IMAGE_VERSION_STRING=video-firmware.1.0-<hash> while SM8250 has
>>> QC_IMAGE_VERSION_STRING=VIDEO.VPU.1.0-00119-<>
>>>
>>> So the driver would need SoC‑specific string‑matching rules, which is hard
>>> to maintain if we are looking for a design to address all available SOCs.
>>
>> The only SoC with such distinction today is kodiak. So we can simply check:
>>
>> if (kodiak && strstr(fw->data, "VIDEO.VPU.1.0.")
>> 	hfi = gen2;
> 
> Agree, this works for Kodiak. However, Dmitry was also referring to other
> SoCs that may support both Gen1 and Gen2, and at the moment there isn’t a
> generic way to handle that check.
> 
> Also, please note that the Kodiak Gen1 firmware uses the string
> video-firmware.1.0, whereas Gen2 uses VIDEO.VPU.3.4.
> 
>>
>>
>> Can we agree that VIDEO.VPU.x firmwares are hfigen2? If so, problem also
>> solved for <=8450
>>
> 
> Nope. that's not true for all, SM8250 uses VIDEO.VPU.1.0 which is gen1.
> 
> Thanks,
> Dikshita
> 
>> Konrad

I really don't see what the problem with Dikshita's proposal here is 
after all she literally controls the firmware name that goes to 
linux-firmware.

Presumably you can attest to the naming format you have-sent and 
will-send in future.

---
bod