Re: [PATCH 09/22] drm/i915: enable IPS bit for 64K pages

Chris Wilson
2017-08-15T18:48:51Z

Quoting Matthew Auld (2017-08-15 19:12:02)
> + /* To support 64K PTE's we need to first enable the use of the
> + * Intermediate-Page-Size(IPS) bit of the PDE field via some magical
> + * mmio, otherwise the page-walker will simply ignore the IPS bit. This
> + * shouldn't be needed after GEN10.
> + */
> + if (HAS_PAGE_SIZE(dev_priv, I915_GTT_PAGE_SIZE_64K) &&

I presume we have some vague acknowledgement that snb+ can do 64k, so
don't we need a IS_GEN(i915, 8, 10) here or is GEN8_GAM_ECO_DEV_RW_IA
badly named? Or was snb just 32k like ilk?

> + INTEL_GEN(dev_priv) <= 10)
> + I915_WRITE(GEN8_GAMW_ECO_DEV_RW_IA,
> + I915_READ(GEN8_GAMW_ECO_DEV_RW_IA) |
> + GAMW_ECO_ENABLE_64K_IPS_FIELD);
> +