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Date:   Wed, 3 Aug 2022 02:25:49 +0900
From:   Jiho Chu <jiho.chu@samsung.com>
To:     Oded Gabbay <oded.gabbay@gmail.com>
Cc:     Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Arnd Bergmann <arnd@arndb.de>,
        "Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>
Subject: Re: New subsystem for acceleration devices
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On Sun, 31 Jul 2022 14:45:34 +0300
Oded Gabbay <oded.gabbay@gmail.com> wrote:

> Hi,
> Greg and I talked a couple of months ago about preparing a new accel
> subsystem for compute/acceleration devices that are not GPUs and I
> think your drivers that you are now trying to upstream fit it as well.
> 
> Would you be open/interested in migrating your drivers to this new subsystem ?
> 
> Because there were no outstanding candidates, I have done so far only
> a basic and partial implementation of the infrastructure for this
> subsystem, but if you are willing to join I believe I can finish it
> rather quickly.
> 
> At start, the new subsystem will provide only a common device
> character (e.g. /dev/acX) so everyone will do open/close/ioctl on the
> same device character. Also sysfs/debugfs entries will be under that
> device and maybe an IOCTL to retrieve information.
> 
> In the future I plan to move some of habanalabs driver's code into the
> subsystem itself, for common tasks such as memory management, dma
> memory allocation, etc.
> 
> Of course, you will be able to add your own IOCTLs as you see fit.
> There will be a range of IOCTLs which are device-specific (similar to
> drm).
> 
> wdyt ?
> 
> Thanks,
> Oded
> 

Hi, Oded.
Thanks for sharing your idea. And I'm really positive on the subsystem for ai acceleration devices.

Samsung NPU driver is trying to upstream now, so I wonder new subsystem can cover all of the operations.
I'll appreciate if you share the code when you ready, so I can figure out our driver can be migrated.

Sincerely,
Jiho Chu