Re: [RFC PATCH v3 2/3] accel: add dedicated minor for accelerator devices

From: Oded Gabbay <ogabbay@kernel.org>
To: Jeffrey Hugo <quic_jhugo@quicinc.com>
Cc: David Airlie <airlied@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
	Arnd Bergmann <arnd@arndb.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
	Jason Gunthorpe <jgg@nvidia.com>,
	John Hubbard <jhubbard@nvidia.com>,
	Alex Deucher <alexander.deucher@amd.com>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	Maxime Ripard <mripard@kernel.org>,
	Thomas Zimmermann <tzimmermann@suse.de>,
	Yuji Ishikawa <yuji2.ishikawa@toshiba.co.jp>,
	Jiho Chu <jiho.chu@samsung.com>,
	Daniel Stone <daniel@fooishbar.org>,
	Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>,
	Christoph Hellwig <hch@infradead.org>,
	Kevin Hilman <khilman@baylibre.com>,
	Jagan Teki <jagan@amarulasolutions.com>,
	Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>,
	Maciej Kwapulinski <maciej.kwapulinski@linux.intel.com>,
	Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>,
	Randy Dunlap <rdunlap@infradead.org>
Subject: Re: [RFC PATCH v3 2/3] accel: add dedicated minor for accelerator devices
Date: Mon, 7 Nov 2022 23:06:41 +0200	[thread overview]
Message-ID: <CAFCwf11AMAYgKHJia87x0gsZ2ufVK1ZQqXqDLLimeeTVQVp2CA@mail.gmail.com> (raw)
In-Reply-To: <2f415e77-9332-2d66-cd59-05db8d5790ea@quicinc.com>

On Mon, Nov 7, 2022 at 6:20 PM Jeffrey Hugo <quic_jhugo@quicinc.com> wrote:
>
> On 11/6/2022 2:02 PM, Oded Gabbay wrote:
> > --- a/drivers/accel/drm_accel.c
> > +++ b/drivers/accel/drm_accel.c
> > @@ -8,14 +8,25 @@
> >
> >   #include <linux/debugfs.h>
> >   #include <linux/device.h>
> > +#include <linux/xarray.h>
>
> If we are not using xarray at this time, do we still need this include?
>
> >
> >   #include <drm/drm_accel.h>
> > +#include <drm/drm_debugfs.h>
> > +#include <drm/drm_drv.h>
> > +#include <drm/drm_file.h>
> >   #include <drm/drm_ioctl.h>
> >   #include <drm/drm_print.h>
> >
> > +static DEFINE_SPINLOCK(accel_minor_lock);
> > +static struct idr accel_minors_idr;
>
> I beleive we should have an explicit include for the IDR header.
>
> > --- a/include/drm/drm_accel.h
> > +++ b/include/drm/drm_accel.h
> > @@ -8,12 +8,56 @@
> >   #ifndef DRM_ACCEL_H_
> >   #define DRM_ACCEL_H_
> >
> > -#define ACCEL_MAJOR     261
> > +#include <drm/drm_file.h>
> > +
> > +#define ACCEL_MAJOR          261
> > +#define ACCEL_MAX_MINORS     256
>
> This diff seems really weird.  The changes to the ACCEL_MAJOR define
> could get pushed to the previous patch, no?
>
> > @@ -23,9 +67,31 @@ static inline void accel_core_exit(void)
> >
> >   static inline int __init accel_core_init(void)
> >   {
> > +     /* Return 0 to allow drm_core_init to complete successfully */
>
> Move to previous patch?
>
> > --- a/include/drm/drm_drv.h
> > +++ b/include/drm/drm_drv.h
> > @@ -94,6 +94,14 @@ enum drm_driver_feature {
> >        * synchronization of command submission.
> >        */
> >       DRIVER_SYNCOBJ_TIMELINE         = BIT(6),
> > +     /**
> > +      * @DRIVER_COMPUTE_ACCEL:
> > +      *
> > +      * Driver supports compute acceleration devices. This flag is mutually exclusive with
> > +      * @DRIVER_RENDER and @DRIVER_MODESET. Devices that support both graphics and compute
> > +      * acceleration should be handled by two drivers that are connected using auxiliry bus.
>
> auxiliry -> auxiliary
>
All comments will be fixed.
Thanks,
Oded