[Intel-gfx] [PATCH 1/2] drm/i915/gt: Re-work intel_write_status_page

[Matthew Auld]

On Thu, 27 Jan 2022 at 23:41, Michael Cheng <michael.cheng at intel.com> wrote:
>
> Re-work intel_write_status_page to use drm_clflush_virt_range. This
> will prevent compiler errors when building for non-x86 architectures.
>
> Signed-off-by: Michael Cheng <michael.cheng at intel.com>
> ---
>  drivers/gpu/drm/i915/gt/intel_engine.h | 13 ++++---------
>  1 file changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_engine.h b/drivers/gpu/drm/i915/gt/intel_engine.h
> index 08559ace0ada..e6189fffa7a3 100644
> --- a/drivers/gpu/drm/i915/gt/intel_engine.h
> +++ b/drivers/gpu/drm/i915/gt/intel_engine.h
> @@ -4,6 +4,7 @@
>
>  #include <asm/cacheflush.h>
>  #include <drm/drm_util.h>
> +#include <drm/drm_cache.h>
>
>  #include <linux/hashtable.h>
>  #include <linux/irq_work.h>
> @@ -144,15 +145,9 @@ intel_write_status_page(struct intel_engine_cs *engine, int reg, u32 value)
>          * of extra paranoia to try and ensure that the HWS takes the value
>          * we give and that it doesn't end up trapped inside the CPU!
>          */
> -       if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
> -               mb();
> -               clflush(&engine->status_page.addr[reg]);
> -               engine->status_page.addr[reg] = value;
> -               clflush(&engine->status_page.addr[reg]);
> -               mb();
> -       } else {
> -               WRITE_ONCE(engine->status_page.addr[reg], value);
> -       }
> +       drm_clflush_virt_range(&engine->status_page.addr[reg], PAGE_SIZE);
> +       WRITE_ONCE(engine->status_page.addr[reg], value);
> +       drm_clflush_virt_range(&engine->status_page.addr[reg], PAGE_SIZE);

s/PAGE_SIZE/sizeof(value) ?

>  }
>
>  /*

> --
> 2.25.1
>