Re: [RFC PATCH v3 1/3] drivers/accel: define kconfig and register a new major

From: Oded Gabbay <ogabbay@kernel.org>
To: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
Cc: dri-devel@lists.freedesktop.org,
	Maciej Kwapulinski <maciej.kwapulinski@linux.intel.com>,
	Kevin Hilman <khilman@baylibre.com>,
	Christoph Hellwig <hch@infradead.org>,
	Jagan Teki <jagan@amarulasolutions.com>,
	Jason Gunthorpe <jgg@nvidia.com>,
	John Hubbard <jhubbard@nvidia.com>,
	Jeffrey Hugo <quic_jhugo@quicinc.com>,
	Arnd Bergmann <arnd@arndb.de>, Jiho Chu <jiho.chu@samsung.com>,
	Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>,
	Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>,
	Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	linux-kernel@vger.kernel.org,
	Thomas Zimmermann <tzimmermann@suse.de>,
	Alex Deucher <alexander.deucher@amd.com>
Subject: Re: [RFC PATCH v3 1/3] drivers/accel: define kconfig and register a new major
Date: Tue, 8 Nov 2022 14:48:17 +0200	[thread overview]
Message-ID: <CAFCwf12D=nEsRyDvbEotXN6xCP+8FPu-d-heTQGzas9DwCPRSQ@mail.gmail.com> (raw)
In-Reply-To: <20221108124614.GA6397@linux.intel.com>

On Tue, Nov 8, 2022 at 2:46 PM Stanislaw Gruszka
<stanislaw.gruszka@linux.intel.com> wrote:
>
> On Sun, Nov 06, 2022 at 11:02:23PM +0200, Oded Gabbay wrote:
> > Add a new Kconfig for the accel subsystem. The Kconfig currently
> > contains only the basic CONFIG_DRM_ACCEL option that will be used to
> > decide whether to compile the accel registration code. Therefore, the
> > kconfig option is defined as bool.
> >
> > The accel code will be compiled as part of drm.ko and will be called
> > directly from the DRM core code. The reason we compile it as part of
> > drm.ko and not as a separate module is because of cyclic dependency
> > between drm.ko and the separate module (if it would have existed).
> > This is due to the fact that DRM core code calls accel functions and
> > vice-versa.
> >
> > The accelerator devices will be exposed to the user space with a new,
> > dedicated major number - 261.
> >
> > The accel init function registers the new major number as a char device
> > and create corresponding sysfs and debugfs root entries, similar to
> > what is done in DRM init function.
> >
> > I added a new header called drm_accel.h to include/drm/, that will hold
> > the prototypes of the drm_accel.c functions. In case CONFIG_DRM_ACCEL
> > is set to 'N', that header will contain empty inline implementations of
> > those functions, to allow DRM core code to compile successfully
> > without dependency on CONFIG_DRM_ACCEL.
> >
> > I Updated the MAINTAINERS file accordingly with the newly added folder
> > and I have taken the liberty to appropriate the dri-devel mailing list
> > and the dri-devel IRC channel for the accel subsystem.
> >
> > Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
>
> Tested-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
>
> I tested those patches with intel_vpu driver. After initial troubles,
> I got things worked with our driver and user mode components.
>
> Regards
> Stanislaw

Thanks!
Great to hear that.
Oded