> -----Original Message----- > From: Ville Syrjälä [mailto:ville.syrjala@xxxxxxxxx] > Sent: Friday, November 26, 2010 6:26 PM > To: Hiremath, Vaibhav > Cc: Måns Rullgård; linux-omap@xxxxxxxxxxxxxxx; linux-fbdev@xxxxxxxxxxxxxxx > Subject: Re: OMAP:DSS: possible bug in WAITFOR_VSYNC ioctl > > On Fri, Nov 26, 2010 at 05:38:11PM +0530, ext Hiremath, Vaibhav wrote: > > > > > -----Original Message----- > > > From: Hiremath, Vaibhav > > > Sent: Friday, November 26, 2010 5:34 PM > > > To: 'Måns Rullgård'; linux-omap@xxxxxxxxxxxxxxx > > > Subject: RE: OMAP:DSS: possible bug in WAITFOR_VSYNC ioctl > > > > > > > -----Original Message----- > > > > From: linux-omap-owner@xxxxxxxxxxxxxxx [mailto:linux-omap- > > > > owner@xxxxxxxxxxxxxxx] On Behalf Of Måns Rullgård > > > > Sent: Friday, November 26, 2010 2:09 PM > > > > To: linux-omap@xxxxxxxxxxxxxxx > > > > Subject: Re: OMAP:DSS: possible bug in WAITFOR_VSYNC ioctl > > > > > > > > "Hiremath, Vaibhav" <hvaibhav@xxxxxx> writes: > > > > > > > > >> -----Original Message----- > > > > >> From: Ville Syrjälä [mailto:ville.syrjala@xxxxxxxxx] > > > > >> Sent: Wednesday, November 24, 2010 10:01 PM > > > > >> To: Hiremath, Vaibhav > > > > >> Cc: Tomi Valkeinen; linux-omap@xxxxxxxxxxxxxxx > > > > >> Subject: Re: OMAP:DSS: possible bug in WAITFOR_VSYNC ioctl > > > > >> > > > > >> On Wed, Nov 24, 2010 at 03:39:44PM +0530, ext Hiremath, Vaibhav > > > wrote: > > > > >> > > > > > >> > > -----Original Message----- > > > > >> > > From: Tomi Valkeinen [mailto:tomi.valkeinen@xxxxxxxxx] > > > > >> > > Sent: Wednesday, November 24, 2010 2:28 PM > > > > >> > > To: Hiremath, Vaibhav > > > > >> > > Cc: linux-omap@xxxxxxxxxxxxxxx > > > > >> > > Subject: Re: OMAP:DSS: possible bug in WAITFOR_VSYNC ioctl > > > > >> > > > > > > >> > > On Tue, 2010-11-23 at 23:46 +0530, ext Hiremath, Vaibhav > wrote: > > > > >> > > > Hi, > > > > > <snip> > > > > >> > > > <snip..> > > > > > > > > As far as WAITFORGO is concerned, I think GO bit concept is > > > > > something OMAP notion/term and doesn't make sense to standardize > > > > > it. Atleast I am not aware of any other architecture having GO bit. > > > > > > > > Naming is minor detail. Feel free to suggest a better one. > > > > > > > [Hiremath, Vaibhav] If I fail to convince on this, then I think the > only > > > left option is to make WAITFORGO ioctl generic. And put a disclaimer > on > > > WAITFORVSYNC, it must not be used in panning use-case. > > > > > > > > [Hiremath, Vaibhav] Also let me bring another point here, > > > > If I understand correctly most of the application libraries (DirectFB, X, > etc..) does use FBIO_WAITFORVSYNC to synchronize with HW, and manage ping > pong mechanism. > > DirectFB uses it also for waiting for vsync. > [Hiremath, Vaibhav] Mat, I am not expert on DirectFb stuff; can you please help me to understand what the use-case is? What DirectFB does/expects on this? Thanks, Vaibhav > > With this finding, in case of OMAP3 we have to use OMAPFB_WAITFORGO > (breaking standard applications). > > Applications using the standard fbdev API won't work with manual update > displays anyway. You need omapfb specific code to handle it so having > another small difference is not a big deal. > > In DirectFB the that's trivial since there's already a simple omap > gfxdriver where you could override the default flip functionality with > WAITFORGO based stuff. > > Or, as I said, you could add another standard ioctl and fix up userspace > to use it where appropriate and if the kernel driver supports it. > > -- > Ville Syrjälä -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
