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Message-ID: <d0ea23ae-8fba-d229-b0f6-dc522f285233@quicinc.com>
Date: Wed, 20 Dec 2023 12:02:45 +0530
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Subject: Re: [PATCH v2 00/34] Qualcomm video encoder and decoder driver
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To: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Dikshita Agarwal
	<quic_dikshita@quicinc.com>,
        <linux-media@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <stanimir.k.varbanov@gmail.com>, <agross@kernel.org>,
        <andersson@kernel.org>, <konrad.dybcio@linaro.org>,
        <mchehab@kernel.org>, <bryan.odonoghue@linaro.org>
CC: <linux-arm-msm@vger.kernel.org>, <quic_abhinavk@quicinc.com>
References: <1702899149-21321-1-git-send-email-quic_dikshita@quicinc.com>
 <a033dfc5-dcf1-4969-ad4d-1836ff9ff0a3@linaro.org>
From: Vikash Garodia <quic_vgarodia@quicinc.com>
In-Reply-To: <a033dfc5-dcf1-4969-ad4d-1836ff9ff0a3@linaro.org>
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Hi Dmitry,

On 12/19/2023 12:08 AM, Dmitry Baryshkov wrote:
> On 18/12/2023 13:31, Dikshita Agarwal wrote:
>> This patch series introduces support for Qualcomm new video acceleration
>> hardware architecture, used for video stream decoding/encoding. This driver
>> is based on new communication protocol between video hardware and application
>> processor.
> 
> This doesn't answer one important point, you have been asked for v1. What is the
> actual change point between Venus and Iris? What has been changed so much that
> it demands a separate driver. This is the main question for the cover letter,
> which has not been answered so far.
> 
> From what I see from you bindings, the hardware is pretty close to what we see
> in the latest venus generations. I asssme that there was a change in the vcodec
> inteface to the firmware and other similar changes. Could you please point out,
> which parts of Venus driver do no longer work or are not applicable for sm8550

The motivation behind having a separate IRIS driver was discussed earlier in [1]
In the same discussion, it was ellaborated on how the impact would be with
change in the new firmware interface and other video layers in the driver. I can
add this in cover letter in the next revision.

We see some duplication of code and to handle the same, the series brings in a
common code reusability between iris and venus. Aligning the common peices of
venus and iris will be a work in progress, once we land the base driver for iris.

Again qualcomm video team does not have a plan to support sm8550/x1e80100 on
venus as the changes are too interleaved to absorb in venus driver. And there is
significant interest in community to start validating video driver on sm8550 or
x1e80100.

[1] https://lore.kernel.org/lkml/8c97d866-1cab-0106-4ab3-3ca070945ef7@quicinc.com/

Regards,
Vikash