Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Content-Type: text/plain;
        charset=utf-8
Mime-Version: 1.0 (1.0)
Subject: Re: [PATCH 0/4] WIP: rockchip mpp for v4l2 video decoder
From:   Ayaka <ayaka@soulik.info>
In-Reply-To: <ef348923cfbd18a2566ec0e3d6af3d75b46c32aa.camel@collabora.com>
Date:   Thu, 31 Jan 2019 23:01:14 +0800
Cc:     linux-media@vger.kernel.org, acourbot@chromium.org,
        nicolas@ndufresne.ca, paul.kocialkowski@bootlin.com,
        jernej.skrabec@gmail.com, joro@8bytes.org, mchehab@kernel.org,
        maxime.ripard@bootlin.com, hverkuil@xs4all.nl,
        thomas.petazzoni@bootlin.com, randy.li@rock-chips.com,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-rockchip@lists.infradead.org
Content-Transfer-Encoding: 8BIT
Message-Id: <77D91D42-9274-4AB8-A34B-C073E0761015@soulik.info>
References: <20190131031333.11905-1-ayaka@soulik.info> <ef348923cfbd18a2566ec0e3d6af3d75b46c32aa.camel@collabora.com>
To:     Ezequiel Garcia <ezequiel@collabora.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


Sent from my iPad

> On Jan 31, 2019, at 10:03 PM, Ezequiel Garcia <ezequiel@collabora.com> wrote:
> 
> Hey Ayaka!
> 
>> On Thu, 2019-01-31 at 11:13 +0800, ayaka wrote:
>> From: Randy 'ayaka' Li <ayaka@soulik.info>
>> 
>> Hello
>>  Those patches are based on the previous vendor driver I post before,
>> but it can apply without the previous one.
>>  I really want to make it work before FOSDEM and I didn't. And upcoming
>> the lunar new year holiday would last two week.
>> 
>>  I have verified the v4l2 part but I meet a problem with power or
>> clock, it would be a complex problem, I would handle to solve it after I
>> am back. But I just tell my design on this kind dirver.
>> 
> 
> This the branch I'm about to submit:
> 
> http://git.infradead.org/users/ezequielg/linux/shortlog/refs/heads/vpu-mpeg-2-almost-ready-for-upstream
> 
> And it has no power issues. Perhaps you can take a look inside,
> you might be just missing a few pm_ statements? Perhaps a devicetree thing?
> 
I don’t think it is a complex problem, just I waste too time on v4l2 part
All the current clock frequency at rk3328 is too low for H.264 decoding you may find my previous mail.
>> A few questions I think you may ask I would like to answer it here.
>> 
> 
> I have another question: is this patchset meant to support for mpeg-2
> decoding only? I can't find any other codec code.
> 
I have not. I would like to move my work on userspace interface later, as I said in IRC.
MPEG-2 is just a simple codec I choose for demo(userspace and some not normal picture coded like fileds) and if there is a codec parser there, I can solve it easily.
Adding support to new codec is not complex in this driver once the interface problem is solved. I just copy the public rockchip mpp userspace library into it. It is the other advantage use the register structure.
But I do like people to merge the final version I submit, I would prove it why later.
> Thanks,
> Ezequiel
> 
>> 1. Why it is based on the previous vendor driver ?
>> The vendor driver I post to mail list is a clean version which having a
>> efficient work flow and those platform dependency controls having been
>> merged into it.
>> 
>> For the stateless device, V4L2 is just another interface for userspace
>> to translate it into registers.
>> 
>> 2. Why use a structure to store register infomation not marco ?
>> I really don't want to define many marcos for a device having more than
>> a hundred of registers. And there are many fields in a registers.
>> 
>> For the VDPU1/VDPU2 which would support more than 10 video codecs, these
>> two devices would re-use many registers for many codecs, It would be
>> hard to show the conflict relations between them in marco but more easy
>> with C union and structure.
>> 
>> BTW, I would prefer to write a number of registers into the device
>> though AHB bus not just generate one then write one, you can save some
>> times here.
>> 
>> 
>> Besides the two previous answers. I really have a big problem with v4l2
>> design. Which would driver wait the work of the previous picture is
>> done, leading a large gap time more idle of the device. 
>> 
>> I am ok the current face that v4l2 stateless driver is not stateless.
>> But it would limit the ability of stateless decoder. It is more flexible
>> to those videos having different resolution or orientation sequences.
>> 
>> But I don't like the method to reconstruct the bitstream in driver, it
>> is a bad idea to limit what data the device want. Those problem is
>> mainly talking in the HEVC slice thread. And it was ironic for the VPx
>> serial codec, which mixed compressed data and umcompress header together
>> and twisted. Even for the ITU H serial codec, it would become a problem
>> in SVC or Google Android CTS test.
>> 
>> And thanks kwiboo, ezequielg and Paulk, I copy some v4l2 code from their
>> code.
>> 
>> Randy Li (1):
>>  staging: video: rockchip: add video codec
>> 
>> ayaka (3):
>>  [WIP]: staging: video: rockchip: add v4l2 common
>>  [WIP] staging: video: rockchip: vdpu2
>>  [TEST]: rockchip: mpp: support qtable
>> 
>> drivers/staging/Kconfig                       |    2 +
>> drivers/staging/Makefile                      |    1 +
>> drivers/staging/rockchip-mpp/Kconfig          |   54 +
>> drivers/staging/rockchip-mpp/Makefile         |    8 +
>> drivers/staging/rockchip-mpp/mpp_debug.h      |   87 ++
>> drivers/staging/rockchip-mpp/mpp_dev_common.c | 1365 +++++++++++++++++
>> drivers/staging/rockchip-mpp/mpp_dev_common.h |  215 +++
>> drivers/staging/rockchip-mpp/mpp_dev_rkvdec.c |  878 +++++++++++
>> drivers/staging/rockchip-mpp/mpp_dev_vdpu2.c  |  755 +++++++++
>> drivers/staging/rockchip-mpp/mpp_service.c    |  197 +++
>> drivers/staging/rockchip-mpp/mpp_service.h    |   38 +
>> drivers/staging/rockchip-mpp/rkvdec/hal.h     |   53 +
>> drivers/staging/rockchip-mpp/rkvdec/regs.h    |  395 +++++
>> drivers/staging/rockchip-mpp/vdpu2/hal.h      |   52 +
>> drivers/staging/rockchip-mpp/vdpu2/mpeg2.c    |  253 +++
>> drivers/staging/rockchip-mpp/vdpu2/regs.h     |  699 +++++++++
>> 16 files changed, 5052 insertions(+)
>> create mode 100644 drivers/staging/rockchip-mpp/Kconfig
>> create mode 100644 drivers/staging/rockchip-mpp/Makefile
>> create mode 100644 drivers/staging/rockchip-mpp/mpp_debug.h
>> create mode 100644 drivers/staging/rockchip-mpp/mpp_dev_common.c
>> create mode 100644 drivers/staging/rockchip-mpp/mpp_dev_common.h
>> create mode 100644 drivers/staging/rockchip-mpp/mpp_dev_rkvdec.c
>> create mode 100644 drivers/staging/rockchip-mpp/mpp_dev_vdpu2.c
>> create mode 100644 drivers/staging/rockchip-mpp/mpp_service.c
>> create mode 100644 drivers/staging/rockchip-mpp/mpp_service.h
>> create mode 100644 drivers/staging/rockchip-mpp/rkvdec/hal.h
>> create mode 100644 drivers/staging/rockchip-mpp/rkvdec/regs.h
>> create mode 100644 drivers/staging/rockchip-mpp/vdpu2/hal.h
>> create mode 100644 drivers/staging/rockchip-mpp/vdpu2/mpeg2.c
>> create mode 100644 drivers/staging/rockchip-mpp/vdpu2/regs.h
>> 
> 
>