Re: [PATCH v7 04/18] media: iris: Filter UBWC raw formats based on hardware capabilities

[Vikash Garodia <vikash.garodia@oss.qualcomm.com>]

On 7/22/2026 3:46 AM, Bryan O'Donoghue wrote:
> On 21/07/2026 17:23, Vikash Garodia wrote:
>>
>> On 7/21/2026 8:34 PM, Dmitry Baryshkov wrote:
>>> On Tue, 21 Jul 2026 at 17:08, Vikash Garodia
>>> <vikash.garodia@oss.qualcomm.com> wrote:
>>>>
>>>>
>>>> On 7/9/2026 7:11 PM, Dmitry Baryshkov wrote:
>>>>> From: Dikshita Agarwal <dikshita.agarwal@oss.qualcomm.com>
>>>>>
>>>>> The raw formats supported by Iris were previously advertised
>>>>> unconditionally, assuming UBWC support on all platforms. However, some
>>>>> platforms do not support UBWC which results in incorrect format
>>>>> capability exposure.
>>>>>
>>>>> Use the UBWC configuration provided by the platform to dynamically
>>>>> filter raw formats at runtime. If UBWC is not supported, UBWC-based
>>>>> formats are omitted from the advertised capability list, while linear
>>>>> formats remain available.
>>>>>
>>>>> Signed-off-by: Dikshita Agarwal <dikshita.agarwal@oss.qualcomm.com>
>>>>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
>>>>> ---
>>>>>     drivers/media/platform/qcom/iris/iris_vdec.c | 26 +++++++++++++ 
>>>>> +++++++++----
>>>>>     drivers/media/platform/qcom/iris/iris_venc.c | 25 +++++++++++++ 
>>>>> ++++++++----
>>>>>     2 files changed, 43 insertions(+), 8 deletions(-)
>>>>>
>>>>> diff --git a/drivers/media/platform/qcom/iris/iris_vdec.c b/ 
>>>>> drivers/media/platform/qcom/iris/iris_vdec.c
>>>>> index 4c8bc7aac135..9fee5f28097d 100644
>>>>> --- a/drivers/media/platform/qcom/iris/iris_vdec.c
>>>>> +++ b/drivers/media/platform/qcom/iris/iris_vdec.c
>>>>> @@ -3,6 +3,7 @@
>>>>>      * Copyright (c) 2022-2024 Qualcomm Innovation Center, Inc. All 
>>>>> rights reserved.
>>>>>      */
>>>>>
>>>>> +#include <linux/soc/qcom/ubwc.h>
>>>>>     #include <media/v4l2-event.h>
>>>>>     #include <media/v4l2-mem2mem.h>
>>>>>
>>>>> @@ -69,8 +70,14 @@ static const u32 iris_vdec_formats_cap[] = {
>>>>>         V4L2_PIX_FMT_QC10C,
>>>>>     };
>>>>>
>>>>> +static const u32 iris_vdec_formats_noubwc_cap[] = {
>>>>> +     V4L2_PIX_FMT_NV12,
>>>>> +     V4L2_PIX_FMT_P010,
>>>>> +};
>>>>> +
>>>>>     static bool check_format(struct iris_inst *inst, u32 pixfmt, 
>>>>> u32 type)
>>>>>     {
>>>>> +     const struct qcom_ubwc_cfg_data *ubwc = inst->core->ubwc_cfg;
>>>>>         unsigned int size, i;
>>>>>         const u32 *fmt;
>>>>>
>>>>> @@ -80,8 +87,13 @@ static bool check_format(struct iris_inst *inst, 
>>>>> u32 pixfmt, u32 type)
>>>>>                 size = inst->core->iris_platform_data- 
>>>>> >inst_iris_fmts_size;
>>>>>                 break;
>>>>>         case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
>>>>> -             fmt = iris_vdec_formats_cap;
>>>>> -             size = ARRAY_SIZE(iris_vdec_formats_cap);
>>>>> +             if (ubwc->ubwc_enc_version) {
>>>>
>>>> Do you see a possibility that ubwc is enabled for a SOC while VPU
>>>> hardware does not support UBWC. IP document for qcom,qcm2290 lists some
>>>> UBWC configuration, while VPU does not support UBWC. Not sure at this
>>>> point if other blocks indeed support UBWC for qcom,qcm2290.
>>>
>>> No, QCM2290 doesn't really support UBWC between the IP cores (as such
>>> it has ubwc_enc_version = 0).
>>> Currently the database defines a least common denominator for all IP
>>> cores. If we ever get to a point where we want to define UBWC params
>>> per the core, we will need to restructure the database.
>>>
>>
>> Ack.
>>
>>
> 
> Ack-by ?

The ack here was to acknowledge the explanation provided towards a 
specific case. R-B tag provided earlier on this patch stands good.

> 
> ---
> bod