RE: [PATCH v2 00/14] drm: Make DRM's IRQ helpers legacy

["Chrisanthus, Anitha" <anitha.chrisanthus@intel.com>]

Hi Thomas,

> -----Original Message-----
> From: Thomas Zimmermann <tzimmermann@suse.de>
> Sent: Wednesday, August 4, 2021 12:11 AM
> To: Chrisanthus, Anitha <anitha.chrisanthus@intel.com>; Sam Ravnborg
> <sam@ravnborg.org>
> Cc: daniel@ffwll.ch; airlied@linux.ie; alexander.deucher@amd.com;
> christian.koenig@amd.com; liviu.dudau@arm.com; brian.starkey@arm.com;
> bbrezillon@kernel.org; nicolas.ferre@microchip.com;
> maarten.lankhorst@linux.intel.com; mripard@kernel.org; stefan@agner.ch;
> alison.wang@nxp.com; patrik.r.jakobsson@gmail.com; robdclark@gmail.com;
> Dea, Edmund J <edmund.j.dea@intel.com>; sean@poorly.run;
> shawnguo@kernel.org; s.hauer@pengutronix.de; kernel@pengutronix.de;
> jyri.sarha@iki.fi; tomba@kernel.org; Dan.Sneddon@microchip.com;
> tomi.valkeinen@ideasonboard.com; amd-gfx@lists.freedesktop.org; dri-
> devel@lists.freedesktop.org; linux-arm-kernel@lists.infradead.org; linux-arm-
> msm@vger.kernel.org; freedreno@lists.freedesktop.org
> Subject: Re: [PATCH v2 00/14] drm: Make DRM's IRQ helpers legacy
> 
> Hi
> 
> Am 03.08.21 um 20:36 schrieb Chrisanthus, Anitha:
> > Hi Thomas,
> > Can you please hold off on applying the kmb patch, I am seeing some issues
> while testing. Modetest works, but video playback only plays once, and it fails
> the second time with this patch.
> 
> Sounds a bit like the testing issue at [1]. For testing, you need the
> latest drm-misc-next or drm-tip. Specifically, you need commit
> 1e4cd78ed493 ("drm: Don't test for IRQ support in VBLANK ioctls").


You are right, with the above patch video plays fine. It's all good now! Sorry about the confusion.
> 
> Let me know whether this works for you.
> 
> Best regards
> Thomas
> 
> [1] https://patchwork.freedesktop.org/patch/447057/?series=93078&rev=1
> 
> >
> > Thanks,
> > Anitha
> >
> >
> >> -----Original Message-----
> >> From: Sam Ravnborg <sam@ravnborg.org>
> >> Sent: Tuesday, August 3, 2021 8:05 AM
> >> To: Thomas Zimmermann <tzimmermann@suse.de>
> >> Cc: daniel@ffwll.ch; airlied@linux.ie; alexander.deucher@amd.com;
> >> christian.koenig@amd.com; liviu.dudau@arm.com;
> brian.starkey@arm.com;
> >> bbrezillon@kernel.org; nicolas.ferre@microchip.com;
> >> maarten.lankhorst@linux.intel.com; mripard@kernel.org;
> stefan@agner.ch;
> >> alison.wang@nxp.com; patrik.r.jakobsson@gmail.com; Chrisanthus, Anitha
> >> <anitha.chrisanthus@intel.com>; robdclark@gmail.com; Dea, Edmund J
> >> <edmund.j.dea@intel.com>; sean@poorly.run; shawnguo@kernel.org;
> >> s.hauer@pengutronix.de; kernel@pengutronix.de; jyri.sarha@iki.fi;
> >> tomba@kernel.org; Dan.Sneddon@microchip.com;
> >> tomi.valkeinen@ideasonboard.com; amd-gfx@lists.freedesktop.org; dri-
> >> devel@lists.freedesktop.org; linux-arm-kernel@lists.infradead.org; linux-
> arm-
> >> msm@vger.kernel.org; freedreno@lists.freedesktop.org
> >> Subject: Re: [PATCH v2 00/14] drm: Make DRM's IRQ helpers legacy
> >>
> >> Hi Thomas,
> >>
> >> On Tue, Aug 03, 2021 at 11:06:50AM +0200, Thomas Zimmermann wrote:
> >>> DRM's IRQ helpers are only helpful for old, non-KMS drivers. Move
> >>> the code behind CONFIG_DRM_LEGACY. Convert KMS drivers to Linux
> >>> IRQ interfaces.
> >>>
> >>> DRM provides IRQ helpers for setting up, receiving and removing IRQ
> >>> handlers. It's an abstraction over plain Linux functions. The code
> >>> is mid-layerish with several callbacks to hook into the rsp drivers.
> >>> Old UMS driver have their interrupts enabled via ioctl, so these
> >>> abstractions makes some sense. Modern KMS manage all their interrupts
> >>> internally. Using the DRM helpers adds indirection without benefits.
> >>>
> >>> Most KMS drivers already use Linux IRQ functions instead of DRM's
> >>> abstraction layer. Patches 1 to 12 convert the remaining ones.
> >>> The patches also resolve a bug for devices without assigned interrupt
> >>> number. DRM helpers don't test for IRQ_NOTCONNECTED, so drivers do
> >>> not detect if the device has no interrupt assigned.
> >>>
> >>> Patch 13 removes an unused function.
> >>>
> >>> Patch 14 moves the DRM IRQ helpers behind CONFIG_DRM_LEGACY. Only
> >>> the old non-KMS drivers still use the functionality.
> >>>
> >>> v2:
> >>> 	* drop IRQ_NOTCONNECTED test from atmel-hlcdc (Sam)
> >>> 	* use devm_request_irq() in atmel-hlcdc (Sam)
> >>> 	* unify variable names in arm/hlcdc (Sam)
> >>>
> >>> Thomas Zimmermann (14):
> >>
> >> The following patches are all:
> >> Acked-by: Sam Ravnborg <sam@ravnborg.org>
> >>
> >>>    drm/fsl-dcu: Convert to Linux IRQ interfaces
> >>>    drm/gma500: Convert to Linux IRQ interfaces
> >>>    drm/kmb: Convert to Linux IRQ interfaces
> >>>    drm/msm: Convert to Linux IRQ interfaces
> >>>    drm/mxsfb: Convert to Linux IRQ interfaces
> >>>    drm/tidss: Convert to Linux IRQ interfaces
> >>>    drm/vc4: Convert to Linux IRQ interfaces
> >>>    drm: Remove unused devm_drm_irq_install()
> >>
> >> The remaining patches I either skipped or already had a feedback from
> >> me or I asked a question.
> >>
> >> 	Sam
> 
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
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