Re: [Intel-gfx] [PATCH v2 2/3] drm/fb-helper: Set framebuffer for vga-switcheroo clients

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Thu, Jan 19, 2023 at 09:06:54AM +0100, Thomas Zimmermann wrote:
> Hi
> 
> Am 18.01.23 um 20:21 schrieb Rodrigo Vivi:
> > On Thu, Jan 12, 2023 at 09:11:55PM +0100, Thomas Zimmermann wrote:
> > > Set the framebuffer info for drivers that support VGA switcheroo. Only
> > > affects the amdgpu and nouveau drivers, which use VGA switcheroo and
> > > generic fbdev emulation. For other drivers, this does nothing.
> > > 
> > > This fixes a potential regression in the console code. Both, amdgpu and
> > > nouveau, invoked vga_switcheroo_client_fb_set() from their internal fbdev
> > > code. But the call got lost when the drivers switched to the generic
> > > emulation.
> > > 
> > > Fixes: 087451f372bf ("drm/amdgpu: use generic fb helpers instead of setting up AMD own's.")
> > > Fixes: 4a16dd9d18a0 ("drm/nouveau/kms: switch to drm fbdev helpers")
> > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> > > Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> > > Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
> > > Cc: Ben Skeggs <bskeggs@redhat.com>
> > > Cc: Karol Herbst <kherbst@redhat.com>
> > > Cc: Lyude Paul <lyude@redhat.com>
> > > Cc: Thomas Zimmermann <tzimmermann@suse.de>
> > > Cc: Javier Martinez Canillas <javierm@redhat.com>
> > > Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > > Cc: Jani Nikula <jani.nikula@intel.com>
> > > Cc: Dave Airlie <airlied@redhat.com>
> > > Cc: Evan Quan <evan.quan@amd.com>
> > > Cc: Christian König <christian.koenig@amd.com>
> > > Cc: Alex Deucher <alexander.deucher@amd.com>
> > > Cc: Hawking Zhang <Hawking.Zhang@amd.com>
> > > Cc: Likun Gao <Likun.Gao@amd.com>
> > > Cc: "Christian König" <christian.koenig@amd.com>
> > > Cc: Stanley Yang <Stanley.Yang@amd.com>
> > > Cc: "Tianci.Yin" <tianci.yin@amd.com>
> > > Cc: Xiaojian Du <Xiaojian.Du@amd.com>
> > > Cc: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
> > > Cc: YiPeng Chai <YiPeng.Chai@amd.com>
> > > Cc: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com>
> > > Cc: Bokun Zhang <Bokun.Zhang@amd.com>
> > > Cc: Guchun Chen <guchun.chen@amd.com>
> > > Cc: Hamza Mahfooz <hamza.mahfooz@amd.com>
> > > Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
> > > Cc: Mario Limonciello <mario.limonciello@amd.com>
> > > Cc: Solomon Chiu <solomon.chiu@amd.com>
> > > Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
> > > Cc: Felix Kuehling <Felix.Kuehling@amd.com>
> > > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > > Cc: "Marek Olšák" <marek.olsak@amd.com>
> > > Cc: Sam Ravnborg <sam@ravnborg.org>
> > > Cc: Hans de Goede <hdegoede@redhat.com>
> > > Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com>
> > > Cc: dri-devel@lists.freedesktop.org
> > > Cc: nouveau@lists.freedesktop.org
> > > Cc: <stable@vger.kernel.org> # v5.17+
> > > ---
> > >   drivers/gpu/drm/drm_fb_helper.c | 8 ++++++++
> > >   1 file changed, 8 insertions(+)
> > > 
> > > diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
> > > index 427631706128..5e445c61252d 100644
> > > --- a/drivers/gpu/drm/drm_fb_helper.c
> > > +++ b/drivers/gpu/drm/drm_fb_helper.c
> > > @@ -30,7 +30,9 @@
> > >   #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> > >   #include <linux/console.h>
> > > +#include <linux/pci.h>
> > >   #include <linux/sysrq.h>
> > > +#include <linux/vga_switcheroo.h>
> > >   #include <drm/drm_atomic.h>
> > >   #include <drm/drm_drv.h>
> > > @@ -1940,6 +1942,7 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
> > >   					 int preferred_bpp)
> > >   {
> > >   	struct drm_client_dev *client = &fb_helper->client;
> > > +	struct drm_device *dev = fb_helper->dev;
> > 
> > On drm-tip, this commit has a silent conflict with
> > cff84bac9922 ("drm/fh-helper: Split fbdev single-probe helper")
> > that's already in drm-next.
> > 
> > I had created a fix-up patch in drm-tip re-introducing this line.
> 
> Thank you. Is it fixed for now?

Fixed in drm-tip, yes. But broke linux-next as well. This
resolution will need to go up with any merge...

> 
> > 
> > We probably need a backmerge from drm-next into drm-misc-fixes with
> > the resolution applied there. And probably propagated that resolution
> > later...
> 
> Backmerging from -next into -fixes branches is a problem, as -fixes should
> be close to the latest release.

doh! Indeed I should've known this by heart... -ENOTEHOUGHCOFFEE

> 
> Can we solve this by merging -fixes into upstream and backmerging this into
> our -next branches?

hmmm... probably better just wait and let folks know the resolution
when the patches are moving up...

> 
> Best regards
> Thomas
> 
> > 
> > >   	struct drm_fb_helper_surface_size sizes;
> > >   	int ret;
> > > @@ -1961,6 +1964,11 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
> > >   		return ret;
> > >   	strcpy(fb_helper->fb->comm, "[fbcon]");
> > > +
> > > +	/* Set the fb info for vgaswitcheroo clients. Does nothing otherwise. */
> > > +	if (dev_is_pci(dev->dev))
> > > +		vga_switcheroo_client_fb_set(to_pci_dev(dev->dev), fb_helper->info);
> > > +
> > >   	return 0;
> > >   }
> > > -- 
> > > 2.39.0
> > > 
> 
> -- 
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany
> (HRB 36809, AG Nürnberg)
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