Re: [PATCH 09/24] drm/i915: Fix location of stolen memory register for SandyBridge+

[Jesse Barnes <jbarnes@virtuousgeek.org>]

On Tue,  4 Sep 2012 21:03:01 +0100
Chris Wilson <chris@chris-wilson.co.uk> wrote:

> A few of the earlier registers where enlarged and so the Base Data of
> Stolem Memory Register (BDSM) was pushed to 0xb0.
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
>  drivers/gpu/drm/i915/i915_gem_stolen.c |    9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
> index a01ff74..a528e4a 100644
> --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
> +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
> @@ -63,7 +63,11 @@ static unsigned long i915_stolen_to_physical(struct drm_device *dev)
>  	 * its value of TOLUD.
>  	 */
>  	base = 0;
> -	if (INTEL_INFO(dev)->gen > 3 || IS_G33(dev)) {
> +	if (INTEL_INFO(dev)->gen >= 6) {
> +		/* Read Base Data of Stolen Memory Register (BDSM) directly */
> +		pci_read_config_dword(pdev, 0xB0, &base);
> +		base &= ~4095; /* lower bits used for locking register */
> +	} 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
> @@ -172,6 +176,9 @@ int i915_gem_init_stolen(struct drm_device *dev)
>  	if (dev_priv->mm.stolen_base == 0)
>  		return 0;
>  
> +	DRM_DEBUG_KMS("found %d bytes of stolen memory at %08lx\n",
> +		      dev_priv->mm.gtt->stolen_size, dev_priv->mm.stolen_base);
> +
>  	/* Basic memrange allocator for stolen space */
>  	drm_mm_init(&dev_priv->mm.stolen, 0, prealloc_size);
>  

A bit scary we've had this around so long?  And now I can't find docs
for this...  Assuming it tests out ok though:

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
-- 
Jesse Barnes, Intel Open Source Technology Center