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

[Dikshita Agarwal <dikshita.agarwal@oss.qualcomm.com>]

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>
>> ---
> 
> [...]
> 
>> +int iris_update_platform_data(struct iris_core *core)
>> +{
>> +	const char *fwname = NULL;
>> +	const struct firmware *fw;
>> +	int ret;
>> +
>> +	if (of_device_is_compatible(core->dev->of_node, "qcom,sc7280-venus")) {
>> +		ret = of_property_read_string_index(core->dev->of_node, "firmware-name", 0,
>> +					    &fwname);
>> +		if (ret)
>> +			return 0;
>> +
>> +		if (strstr(fwname, "gen2")) {
>> +			ret = request_firmware(&fw, fwname, core->dev);
>> +			if (ret) {
>> +				dev_err(core->dev, "Specified firmware is not present\n");
>> +				return ret;
> 
> This is fragile - if someone names names their gen1 firmware something like
> "myproduct_gen2_vidfw.mbn", it's going to match..
> 
> Could we instead do something like the explicit format checks in
> venus/hfi_msgs.c : sys_get_prop_image_version(), based on the **contents**
> of the binary?
> 

I agree that checking for "gen2" as a substring in the firmware name is not
reliable. Unfortunately, we cannot
usevenus/hfi_msgs.c:sys_get_prop_image_version() (or any Gen1 HFI query) to
probe the contents of the binary here, because Gen1 vs Gen2 have
incompatible HFI protocols—probing a Gen2 image with Gen1 HFI (or
vice‑versa) isn’t viable in this path.

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
want to use Gen2 can opt in by naming the firmware accordingly.

Thanks,
Dikshita

> Konrad