From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH v2] drm/bochs: add edid present check Date: Thu, 20 Dec 2018 09:30:27 +0100 Message-ID: <20181220083027.GF21184@phenom.ffwll.local> References: <20181220065001.9594-1-kraxel@redhat.com> <20181220082826.GE21184@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20181220082826.GE21184@phenom.ffwll.local> Sender: linux-kernel-owner@vger.kernel.org To: Gerd Hoffmann Cc: dri-devel@lists.freedesktop.org, andr2000@gmail.com, David Airlie , open list , "open list:DRM DRIVER FOR BOCHS VIRTUAL GPU" List-Id: dri-devel@lists.freedesktop.org On Thu, Dec 20, 2018 at 09:28:26AM +0100, Daniel Vetter wrote: > On Thu, Dec 20, 2018 at 07:50:01AM +0100, Gerd Hoffmann wrote: > > Check first two header bytes before trying to read the edid blob, > > to avoid the log being spammed in case qemu has no edid support (old > > qemu or edid turned off). > > > > Fixes: 01f23459cf drm/bochs: add edid support. > > Signed-off-by: Gerd Hoffmann > > It's a bit a hack, but makes sense. On 2nd thought, maybe make it less of a hack by reading all 8 bytes of the header and checking it with drm_edit_is_valid(). -Daniel > > Acked-by: Daniel Vetter > > --- > > drivers/gpu/drm/bochs/bochs_hw.c | 8 ++++++++ > > 1 file changed, 8 insertions(+) > > > > diff --git a/drivers/gpu/drm/bochs/bochs_hw.c b/drivers/gpu/drm/bochs/bochs_hw.c > > index c90a0d492f..e1f8ffce00 100644 > > --- a/drivers/gpu/drm/bochs/bochs_hw.c > > +++ b/drivers/gpu/drm/bochs/bochs_hw.c > > @@ -89,6 +89,14 @@ int bochs_hw_load_edid(struct bochs_device *bochs) > > if (!bochs->mmio) > > return -1; > > > > + /* > > + * Check first two EDID blob header bytes to figure whenever > > + * edid support is enabled in qemu. > > + */ > > + if (readb(bochs->mmio + 0) != 0x00 || > > + readb(bochs->mmio + 1) != 0xff) > > + return -1; > > + > > kfree(bochs->edid); > > bochs->edid = drm_do_get_edid(&bochs->connector, > > bochs_get_edid_block, bochs); > > -- > > 2.9.3 > > > > _______________________________________________ > > dri-devel mailing list > > dri-devel@lists.freedesktop.org > > https://lists.freedesktop.org/mailman/listinfo/dri-devel > > -- > Daniel Vetter > Software Engineer, Intel Corporation > http://blog.ffwll.ch -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch