[PATCH] drm/i915: Disable stolen on 865G

[PATCH] drm/i915: Disable stolen on 865G

[Chris Wilson]

It appears our calculation for the address of stolen memory is incorrect
for 865G, so for the time being disable our use of that memory.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96473
Fixes: 0ad98c74e093 ("drm/i915: Deatermine the stolen memory base address...")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
---
 drivers/gpu/drm/i915/i915_gem_stolen.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index e1791fe96674..8b501ddbc784 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -122,6 +122,7 @@ static unsigned long i915_stolen_to_physical(struct drm_device *dev)
 		 * always at TOUD? Ie. is it always the last
 		 * one to be allocated by the BIOS?
 		 */
+		if (0) /* https://bugs.freedesktop.org/show_bug.cgi?id=96473 */
 		pci_bus_read_config_word(dev->pdev->bus, PCI_DEVFN(0, 0),
 					 I865_TOUD, &toud);
 
-- 
2.8.1

Re: [PATCH] drm/i915: Disable stolen on 865G

[Daniel Vetter]

On Thu, Aug 04, 2016 at 10:56:04AM +0100, Chris Wilson wrote:
> It appears our calculation for the address of stolen memory is incorrect
> for 865G, so for the time being disable our use of that memory.
> 
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96473
> Fixes: 0ad98c74e093 ("drm/i915: Deatermine the stolen memory base address...")
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Ville Syrj�l� <ville.syrjala@linux.intel.com>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Cc: stable@vger.kernel.org

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> ---
>  drivers/gpu/drm/i915/i915_gem_stolen.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
> index e1791fe96674..8b501ddbc784 100644
> --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
> +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
> @@ -122,6 +122,7 @@ static unsigned long i915_stolen_to_physical(struct drm_device *dev)
>  		 * always at TOUD? Ie. is it always the last
>  		 * one to be allocated by the BIOS?
>  		 */
> +		if (0) /* https://bugs.freedesktop.org/show_bug.cgi?id=96473 */
>  		pci_bus_read_config_word(dev->pdev->bus, PCI_DEVFN(0, 0),
>  					 I865_TOUD, &toud);
>  
> -- 
> 2.8.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH] drm/i915: Disable stolen on 865G

[Ville Syrjälä]

On Thu, Aug 04, 2016 at 06:31:21PM +0200, Daniel Vetter wrote:
> On Thu, Aug 04, 2016 at 10:56:04AM +0100, Chris Wilson wrote:
> > It appears our calculation for the address of stolen memory is incorrect
> > for 865G, so for the time being disable our use of that memory.
> > 
> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96473
> > Fixes: 0ad98c74e093 ("drm/i915: Deatermine the stolen memory base address...")
> > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> > Cc: Ville Syrj�l� <ville.syrjala@linux.intel.com>
> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Cc: stable@vger.kernel.org
> 
> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

There's a potentially better patch (one that actually fixes the stolen
base calculation) attached to the bug.

> > ---
> >  drivers/gpu/drm/i915/i915_gem_stolen.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
> > index e1791fe96674..8b501ddbc784 100644
> > --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
> > +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
> > @@ -122,6 +122,7 @@ static unsigned long i915_stolen_to_physical(struct drm_device *dev)
> >  		 * always at TOUD? Ie. is it always the last
> >  		 * one to be allocated by the BIOS?
> >  		 */
> > +		if (0) /* https://bugs.freedesktop.org/show_bug.cgi?id=96473 */
> >  		pci_bus_read_config_word(dev->pdev->bus, PCI_DEVFN(0, 0),
> >  					 I865_TOUD, &toud);
> >  
> > -- 
> > 2.8.1
> > 
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch

-- 
Ville Syrj�l�
Intel OTC

Re: [PATCH] drm/i915: Disable stolen on 865G

[Chris Wilson]

On Thu, Aug 04, 2016 at 07:44:14PM +0300, Ville Syrj�l� wrote:
> On Thu, Aug 04, 2016 at 06:31:21PM +0200, Daniel Vetter wrote:
> > On Thu, Aug 04, 2016 at 10:56:04AM +0100, Chris Wilson wrote:
> > > It appears our calculation for the address of stolen memory is incorrect
> > > for 865G, so for the time being disable our use of that memory.
> > > 
> > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96473
> > > Fixes: 0ad98c74e093 ("drm/i915: Deatermine the stolen memory base address...")
> > > Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> > > Cc: Ville Syrj�l� <ville.syrjala@linux.intel.com>
> > > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > > Cc: stable@vger.kernel.org
> > 
> > Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> 
> There's a potentially better patch (one that actually fixes the stolen
> base calculation) attached to the bug.

Yup, holding off on this and thanks for the patch :)
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre