Re: [PATCH v3 24/37] drm/i915: set num_fence_regs to 0 if there is no aperture

Daniele Ceraolo Spurio
2019-08-09T22:46:32Z

On 8/9/19 3:26 PM, Matthew Auld wrote:
> From: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
>
> We can't fence anything without aperture.

When I wrote this patch (before LMEM was in the picture) mappable
aperture was supposed to only be missing in headless scenarios so I
didn't consider the display case. Do we still need/use fences for direct
access from display HW to LMEM? if so, we should drop this.

Daniele

>
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
> Signed-off-by: Stuart Summers <stuart.summers@intel.com>
> Cc: Matthew Auld <matthew.auld@intel.com>
> ---
> drivers/gpu/drm/i915/i915_gem_fence_reg.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_gem_fence_reg.c b/drivers/gpu/drm/i915/i915_gem_fence_reg.c
> index bcac359ec661..bb7d9321cadf 100644
> --- a/drivers/gpu/drm/i915/i915_gem_fence_reg.c
> +++ b/drivers/gpu/drm/i915/i915_gem_fence_reg.c
> @@ -808,8 +808,10 @@ void i915_ggtt_init_fences(struct i915_ggtt *ggtt)
>
> detect_bit_6_swizzle(i915);
>
> - if (INTEL_GEN(i915) >= 7 &&
> - !(IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)))
> + if (!HAS_MAPPABLE_APERTURE(i915))
> + num_fences = 0;
> + else if (INTEL_GEN(i915) >= 7 &&
> + !(IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)))
> num_fences = 32;
> else if (INTEL_GEN(i915) >= 4 ||
> IS_I945G(i915) || IS_I945GM(i915) ||
>
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org