On Tue, 23 Apr 2013 23:15:30 -0700
Ben Widawsky <ben at bwidawsk.net> wrote:
> Because PPGTT PDEs within the GTT are calculated in cachelines
> (HW guys consistency ftw) we do a divide which will wreak havoc if this
> is wrong, and I know that from experience).
>
> If/when we move to multiple PPGTTs this will have to become a WARN, and
> return an error. For now however it should always be considered fatal,
> and only a developer could hit it.
>
> Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
> ---
> drivers/gpu/drm/i915/i915_gem_gtt.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
> index 50df194..0503f09 100644
> --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
> @@ -85,6 +85,8 @@ static int gen6_ppgtt_enable(struct drm_device *dev)
> uint32_t pd_entry;
> int i;
>
> + BUG_ON(ppgtt->pd_offset & 0x3f);
> +
> pd_addr = (gen6_gtt_pte_t __iomem*)dev_priv->gtt.gsm +
> ppgtt->pd_offset / sizeof(gen6_gtt_pte_t);
> for (i = 0; i < ppgtt->num_pd_entries; i++) {
Reviewed-by: Jesse Barnes <jbarnes at virtuousgeek.org>
--
Jesse Barnes, Intel Open Source Technology Center
