Re: kernel.org 6.5.4 , NPU driver, --not support (RFC)

[Tomeu Vizoso]

On Thu, Jan 11, 2024 at 2:14 PM Oded Gabbay <ogabbay@xxxxxxxxxx> wrote:
>
> On 11/01/2024 10:04, Tomeu Vizoso wrote:
> > Hi Oded,
> >
> > Out of curiosity, did you end up taking a look at Amlogic's driver?
> >
> > Cheers,
> >
> > Tomeu
> Hi Tomeu,
> Yes, I have looked at the driver's code. It was not an in-depth review,
> but I tried to mainly understand the features the driver provide to the
> user and how much complex it is.
>
>  From what I could see, this is a full-fledged accelerator which
> requires command submission/completion handling, memory management,
> information and debug capabilities and more.
>
> Therefore, I do think the correct place is in the accel sub-system,
> which will require you to convert the driver to use drm (we can discuss
> exactly what is the level of integration required).
>
> As I said, I didn't do a full-fledged review, but please note the driver
> has a lot of OS-wrapper code, which is not acceptable in the Linux
> kernel, so you will have to clean all the up.

Thanks, Oded.

I'm wondering now about the requirement for open userspace. Do we have
it for this one?

Cheers,

Tomeu

> Thanks,
> Oded
>
> >
> > On Sat, Oct 7, 2023 at 8:37 AM Cancan Chang <Cancan.Chang@xxxxxxxxxxx> wrote:
> >>
> >> Oded,
> >>         You can get the driver code from  github link： https://github.com/OldDaddy9/driver
> >>          e.g.  git clone https://github.com/OldDaddy9/driver.git
> >>
> >> ________________________________________
> >> 发件人: Oded Gabbay <ogabbay@xxxxxxxxxx>
> >> 发送时间: 2023年10月3日 18:52
> >> 收件人: Cancan Chang
> >> 抄送: Jagan Teki; linux-media; linux-kernel; Dave Airlie; Daniel Vetter
> >> 主题: Re: kernel.org 6.5.4 , NPU driver, --not support (RFC)
> >>
> >> [ EXTERNAL EMAIL ]
> >>
> >> On Thu, Sep 28, 2023 at 11:16 AM Cancan Chang <Cancan.Chang@xxxxxxxxxxx> wrote:
> >>>
> >>> “What happens if you call this again without waiting for the previous
> >>> inference to complete ?”
> >>>     --- There is a work-queue in the driver to manage inference tasks.
> >>>           When two consecutive inference tasks occur, the second inference task will be add to
> >>>           the "pending list". While the previous inference task ends, the second inference task will
> >>>           switch to the "scheduled list", and be executed.
> >>>           Each inference task has an id,  "inferece" and "wait until finish" are paired.
> >>>
> >>>           thanks
> >> Thanks for the clarification.
> >> I'll wait for your driver's code link. It doesn't have to be a patch
> >> series at this point. A link to a git repo is enough.
> >> I just want to do a quick pass.
> >>
> >> Thanks,
> >> Oded
> >>
> >>
> >>
> >>>
> >>> ________________________________________
> >>> 发件人: Oded Gabbay <ogabbay@xxxxxxxxxx>
> >>> 发送时间: 2023年9月28日 15:40
> >>> 收件人: Cancan Chang
> >>> 抄送: Jagan Teki; linux-media; linux-kernel; Dave Airlie; Daniel Vetter
> >>> 主题: Re: kernel.org 6.5.4 , NPU driver, --not support (RFC)
> >>>
> >>> [ EXTERNAL EMAIL ]
> >>>
> >>> On Thu, Sep 28, 2023 at 10:25 AM Cancan Chang <Cancan.Chang@xxxxxxxxxxx> wrote:
> >>>>
> >>>> “Could you please post a link to the driver's source code ?
> >>>> In addition, could you please elaborate which userspace libraries
> >>>> exists that work with your driver ? Are any of them open-source ?”
> >>>> --- We will prepare the adla driver link after the holiday on October 6th.
> >>>>       It's a pity that there is no open-source userspace library.
> >>>>       But you can probably understand it through a workflow, which can be simplified as:
> >>>>       1. create model context
> >>>>            ret = ioctl(context->fd, ADLAK_IOCTL_REGISTER_NETWORK, &desc);
> >>>>       2.  set inputs
> >>>>       3.  inference
> >>>>             ret = ioctl(context->fd, ADLAK_IOCTL_INVOKE, &invoke_dec);
> >>> What happens if you call this again without waiting for the previous
> >>> inference to complete ?
> >>> Oded
> >>>>       4.  wait for the inference to complete
> >>>>             ret = ioctl(context->fd, ADLAK_IOCTL_WAIT_UNTIL_FINISH, &stat_req_desc);
> >>>>       5.  destroy model context
> >>>>             ret = ioctl(context->fd, ADLAK_IOCTL_DESTROY_NETWORK, &submit_del);
> >>>>
> >>>>
> >>>>        thanks
> >>>>
> >>>>
> >>>> ________________________________________
> >>>> 发件人: Oded Gabbay <ogabbay@xxxxxxxxxx>
> >>>> 发送时间: 2023年9月28日 13:28
> >>>> 收件人: Cancan Chang
> >>>> 抄送: Jagan Teki; linux-media; linux-kernel; Dave Airlie; Daniel Vetter
> >>>> 主题: Re: kernel.org 6.5.4 , NPU driver, --not support (RFC)
> >>>>
> >>>> [ EXTERNAL EMAIL ]
> >>>>
> >>>> On Wed, Sep 27, 2023 at 10:01 AM Cancan Chang <Cancan.Chang@xxxxxxxxxxx> wrote:
> >>>>>
> >>>>> “Or do you handle one cmd at a time, where the user sends a cmd buffer
> >>>>> to the driver and the driver then submit it by writing to a couple of
> >>>>> registers and polls on some status register until its done, or waits
> >>>>> for an interrupt to mark it as done ?”
> >>>>>    --- yes， user sends a cmd buffer to driver, and driver triggers hardware by writing to register,
> >>>>>          and then, waits for an interrupt to mark it  as done.
> >>>>>
> >>>>>      My current driver is very different from drm, so I want to know if I have to switch to drm？
> >>>> Could you please post a link to the driver's source code ?
> >>>> In addition, could you please elaborate which userspace libraries
> >>>> exists that work with your driver ? Are any of them open-source ?
> >>>>
> >>>>>      Maybe I can refer to /driver/accel/habanalabs.
> >>>> That's definitely a possibility.
> >>>>
> >>>> Oded
> >>>>>
> >>>>> thanks
> >>>>>
> >>>>> ________________________________________
> >>>>> 发件人: Oded Gabbay <ogabbay@xxxxxxxxxx>
> >>>>> 发送时间: 2023年9月26日 20:54
> >>>>> 收件人: Cancan Chang
> >>>>> 抄送: Jagan Teki; linux-media; linux-kernel; Dave Airlie; Daniel Vetter
> >>>>> 主题: Re: kernel.org 6.5.4 , NPU driver, --not support (RFC)
> >>>>>
> >>>>> [ EXTERNAL EMAIL ]
> >>>>>
> >>>>> On Mon, Sep 25, 2023 at 12:29 PM Cancan Chang <Cancan.Chang@xxxxxxxxxxx> wrote:
> >>>>>>
> >>>>>> Thank you for your reply from Jagan & Oded.
> >>>>>>
> >>>>>> It is very appropritate for my driver to be placed in driver/accel.
> >>>>>>
> >>>>>> My accelerator is named ADLA(Amlogic Deep Learning Accelerator).
> >>>>>> It is an IP in SOC,mainly used for neural network models acceleration.
> >>>>>> It will split and compile the neural network model into a private format cmd buffer,
> >>>>>> and submit this cmd buffer to ADLA hardware. It is not programmable device.
> >>>>> What exactly does it mean to "submit this cmd buffer to ADLA hardware" ?
> >>>>>
> >>>>> Does your h/w provides queues for the user/driver to put their
> >>>>> workloads/cmd-bufs on them ? And does it provide some completion queue
> >>>>> to notify when the work is completed?
> >>>>>
> >>>>> Or do you handle one cmd at a time, where the user sends a cmd buffer
> >>>>> to the driver and the driver then submit it by writing to a couple of
> >>>>> registers and polls on some status register until its done, or waits
> >>>>> for an interrupt to mark it as done ?
> >>>>>
> >>>>>>
> >>>>>> ADLA includes four hardware engines:
> >>>>>> RS engines             : working for the reshape operators
> >>>>>> MAC engines         : working for the convolution operators
> >>>>>> DW engines           : working for the planer & Elementwise operators
> >>>>>> Activation engines : working for activation operators(ReLu,tanh..)
> >>>>>>
> >>>>>> By the way, my IP is mainly used for SOC, and the current driver registration is through the platform_driver,
> >>>>>> is it necessary to switch to drm?
> >>>>> This probably depends on the answer to my question above. btw, there
> >>>>> are drivers in drm that handle IPs that are part of an SOC, so
> >>>>> platform_driver is supported.
> >>>>>
> >>>>> Oded
> >>>>>
> >>>>>>
> >>>>>> thanks.
> >>>>>>
> >>>>>> ________________________________________
> >>>>>> 发件人: Oded Gabbay <ogabbay@xxxxxxxxxx>
> >>>>>> 发送时间: 2023年9月22日 23:08
> >>>>>> 收件人: Jagan Teki
> >>>>>> 抄送: Cancan Chang; linux-media; linux-kernel; Dave Airlie; Daniel Vetter
> >>>>>> 主题: Re: kernel.org 6.5.4 , NPU driver, --not support (RFC)
> >>>>>>
> >>>>>> [你通常不会收到来自 ogabbay@xxxxxxxxxx 的电子邮件。请访问 https://aka.ms/LearnAboutSenderIdentification，以了解这一点为什么很重要;]
> >>>>>>
> >>>>>> [ EXTERNAL EMAIL ]
> >>>>>>
> >>>>>> On Fri, Sep 22, 2023 at 12:38 PM Jagan Teki <jagan@edgebleai> wrote:
> >>>>>>>
> >>>>>>> On Fri, 22 Sept 2023 at 15:04, Cancan Chang <Cancan.Chang@amlogiccom> wrote:
> >>>>>>>>
> >>>>>>>> Dear Media Maintainers:
> >>>>>>>>       Thanks for your attention. Before describing my problem，let me introduce to you what I  mean by NPU.
> >>>>>>>>       NPU is Neural Processing Unit, It is designed for deep learning acceleration, It is also called TPU, APU ..
> >>>>>>>>
> >>>>>>>>       The real problems:
> >>>>>>>>        When I was about to upstream my NPU driver codes to linux mainline, i meet two problems:
> >>>>>>>>          1.  According to my research, There is no NPU module path in the linux (base on linux 6.5.4) , I have searched all linux projects and found no organization or comany that has submitted NPU code. Is there a path prepared for NPU driver currently?
> >>>>>>>>          2.   If there is no NPU driver path currently, I am going to put my NPU driver code in the drivers/media/platform/amlogic/ , because my NPU driver belongs to amlogic. and amlogic NPU is mainly used for AI vision applications. Is this plan suitabe for you?
> >>>>>>>
> >>>>>>> If I'm correct about the discussion with Oded Gabby before. I think
> >>>>>>> the drivers/accel/ is proper for AI Accelerators including NPU.
> >>>>>>>
> >>>>>>> + Oded in case he can comment.
> >>>>>>>
> >>>>>>> Thanks,
> >>>>>>> Jagan.
> >>>>>> Thanks Jagan for adding me to this thread. Adding Dave & Daniel as well.
> >>>>>>
> >>>>>> Indeed, the drivers/accel is the place for Accelerators, mainly for
> >>>>>> AI/Deep-Learning accelerators.
> >>>>>> We currently have 3 drivers there already.
> >>>>>>
> >>>>>> The accel subsystem is part of the larger drm subsystem. Basically, to
> >>>>>> get into accel, you need to integrate your driver with the drm at the
> >>>>>> basic level (registering a device, hooking up with the proper
> >>>>>> callbacks). ofc the more you use code from drm, the better.
> >>>>>> You can take a look at the drivers under accel for some examples on
> >>>>>> how to do that.
> >>>>>>
> >>>>>> Could you please describe in a couple of sentences what your
> >>>>>> accelerator does, which engines it contains, how you program it. ie.
> >>>>>> Is it a fixed-function device where you write to a couple of registers
> >>>>>> to execute workloads, or is it a fully programmable device where you
> >>>>>> load compiled code into it (GPU style) ?
> >>>>>>
> >>>>>> For better background on the accel subsystem, please read the following:
> >>>>>> https://docs.kernel.org/accel/introduction.html
> >>>>>> This introduction also contains links to other important email threads
> >>>>>> and to Dave Airlie's BOF summary in LPC2022.
> >>>>>>
> >>>>>> Thanks,
> >>>>>> Oded
>
>