[Intel-gfx] [PATCH] drm/i915: Read the Base of Stolen Memory for 915gm

[Daniel Vetter]

On Sun, Feb 10, 2013 at 01:37:52PM -0800, Ben Widawsky wrote:
> On Sun, Feb 10, 2013 at 07:38:13PM +0000, Chris Wilson wrote:
> > Reading the cspec pays dividends once again, as I found the 'Base of
> > Stolen Memory' config register so that we can skip the fragile
> > computation from Top of Usable Draw and use the real value provided by
> > the BIOS.
> > 
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Don't really want to dig out the doc, but I so prefer this to the
> old way.
> Acked-by: Ben Widawsky <ben at bwidawsk.net>

Hm, sloppy me didn't send out the "patch merged" spam. Anyway:

stolen + phys_object = kaboom

Dropped the patcha again.
-Daniel
> 
> > ---
> >  drivers/gpu/drm/i915/i915_gem_stolen.c |    9 +++------
> >  1 file changed, 3 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
> > index 130d1db..7f1735c 100644
> > --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
> > +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
> > @@ -72,13 +72,10 @@ static unsigned long i915_stolen_to_physical(struct drm_device *dev)
> >  	} else if (INTEL_INFO(dev)->gen > 3 || IS_G33(dev)) {
> >  		/* Read Graphics Base of Stolen Memory directly */
> >  		pci_read_config_dword(pdev, 0xA4, &base);
> > -#if 0
> >  	} else if (IS_GEN3(dev)) {
> > -		u8 val;
> > -		/* Stolen is immediately below Top of Low Usable DRAM */
> > -		pci_read_config_byte(pdev, 0x9c, &val);
> > -		base = val >> 3 << 27;
> > -		base -= dev_priv->mm.gtt->stolen_size;
> > +		/* Read D2:F0 Base of Stolen Memory directly */
> > +		pci_read_config_dword(dev->pdev, 0x5c, &base);
> > +#if 0
> >  	} else {
> >  		/* Stolen is immediately above Top of Memory */
> >  		base = max_low_pfn_mapped << PAGE_SHIFT;
> > -- 
> > 1.7.10.4
> > 
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> -- 
> Ben Widawsky, Intel Open Source Technology Center
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch