Re: hostb(4) and vgapci(4) patch

On Friday 16 December 2005 03:22 pm, John Baldwin wrote:
> On Thursday 15 December 2005 09:33 pm, Anish Mistry wrote:
> > On Thursday 15 December 2005 04:31 pm, you wrote:
> > > On Thursday 15 December 2005 12:32 am, Anish Mistry wrote:
> > > > On Wednesday 14 December 2005 05:20 pm, John Baldwin wrote:
> > > > > I have a patch that is an attempt to untangle a few things
> > > > > in relation to Host-PCI bridges and VGA PCI devices. 
> > > > > Basically, the change is to create a more "real" hostb
> > > > > driver as well as a new vgapci driver and to change agp,
> > > > > drm, and acpi_video to attach to these drivers.  This means
> > > > > among other things:
> > > > >
> > > > > - In theory you can now kldload agp after boot since it
> > > > > still has a place to attach to.
> > > > > - i830/915 drm is no longer a child of agp, instead both
> > > > > become children of vgapci0.
> > > > > - You can now use acpi_video with drm as both attach as
> > > > > children of vgapci0. - This provides a way for us to
> > > > > possibly solve the DPMS problem for suspend/resume
> > > > > (including a cleaner way to do the hack dpms patch I posted
> > > > > to acpi_at_ a long while ago that several people still use).
> > > > >
> > > > > Some other details include:
> > > > >
> > > > > - agp devices no longer map the _entire_ aperture into
> > > > > contiguous KVA meaning that it might be possible now to use
> > > > > a 256 MB aperture without panicing - I've added a new
> > > > > pci_if.m method for locating a specific capability for a
> > > > > PCI device.
> > > > >
> > > > > I have tested this on my laptop and verified that dri still
> > > > > works, but it needs some wider testing, especially the
> > > > > i830/i915 case is slightly more complicated.  Also, this is
> > > > > not going to work with the nvidia-driver currently, but
> > > > > that's something that can be fixed in the future.  If the
> > > > > agp non-mapping does fix the 256 MB aperture issues then I
> > > > > will probably MFC that part to RELENG_6.
> > > > >
> > > > > http://www.FreeBSD.org/~jhb/patches/agp_cvs.patch
> > > >
> > > > Thank you!  It seems to work as advertised.  I'm running
> > > > mach64 DRM with the DPMS patch acpi_video and they both work.
> > > > :) One small problem though.  When I unload the acpi_video
> > > > module and reload it I get the following:
> > > > littleguy# kldload acpi_video
> > > > acpi_video0: <ACPI video extension> on vgapci0
> > > > acpi_video1: <ACPI video extension> on vgapci0
> > > > littleguy# kldunload acpi_video
> > > > acpi_video0: detached
> > > > acpi_video1: detached
> > > > littleguy# kldunload acpi_video
> > > > kldunload: can't find file acpi_video: No such file or
> > > > directory littleguy# kldload acpi_video
> > > > acpi_video0: <ACPI video extension> on vgapci0
> > > > acpi_video1: <ACPI video extension> on vgapci0
> > > > acpi_video2: <ACPI video extension> on vgapci0
> > > > littleguy#
> > > > It also created multiple sysctls with subsequent loads:
> > > > hw.acpi.video.crt0.active: 1
> > > > hw.acpi.video.lcd0.active: 1
> > > > hw.acpi.video.tv0.active: 0
> > > > hw.acpi.video.crt1.active: 1
> > > > hw.acpi.video.lcd1.active: 1
> > > > hw.acpi.video.tv1.active: 0
> > > > hw.acpi.video.crt2.active: 1
> > > > hw.acpi.video.lcd2.active: 1
> > > > hw.acpi.video.tv2.active: 0
> > >
> > > Revert just the changes to acpi_video.c and then apply the
> > > attached patch to see if it fixes the multiple load issue.
> >
> > Yes.  The patch corrects the problem.
>
> Actually, can you try a simpler one just to be sure?  Thanks.
I just enabled witness for my previous problem and got LOR #155, but 
the lines numbers are slightly different, probably just normal 
updates.  I tried to reproduce it with the old patch, but I couldn't.  
So it seems that something else triggered it during the kldunload.

The current patch works fine.

-- 
Anish Mistry