Re: [PATCH v5 1/4] dt-bindings: media: qcom,venus-common: Add IOMMU IOVA reservation region

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 7/23/26 12:03 AM, Bryan O'Donoghue wrote:
> On 22/07/2026 14:41, Vikash Garodia wrote:
>> Update the memory-region property to support two regions:
>> 1. Firmware-loaded codec carveout (existing)
>> 2. IOMMU IOVA reservation region (new)
>>
>> The IOMMU IOVA reservation region is required to restrict usage of
>> specific IOVA memory range. For example, VPU restricts usage of 600MB
>> for specific streams, which could otherwise lead to device crash. This
>> change allows platforms to define separate memory regions for codec
>> carveout and IOVA restrictions.
>> This schema update supports existing DTS having single memory-region,
>> thereby allowing gradual migration of DTS to support two memory region.
>>
>> Signed-off-by: Vikash Garodia<vikash.garodia@oss.qualcomm.com>
>> ---
> 
> I'm not mega-happy with this pattern being used - I prefer the pixel pixel_cb sub-node model you've proposed yourself.
> 
> OTOH you're the maintainer so its really up to you how you want to arbitrate this - the 600MB constraint will work even if its not pretty or the best thing (tm).
> 
> Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>

Doesn't this cause the same limitation that the initial patch
by Daniel (all HW contexts can't access 0-600MiB anymore)?

Konrad