[PATCH v2 8/8] drm/panfrost: Remove unnecessary flushing from tlb_inv_context

[Steven Price]

On 23/08/2019 03:12, Rob Herring wrote:
> tlb_inv_context() hook is only called when freeing the page tables. There's
> no point in flushing only to free the page tables immediately following.
> There is also a problem that we could be accessing the h/w when suspended.
> 
> Cc: Tomeu Vizoso <tomeu.vizoso at collabora.com>
> Cc: Steven Price <steven.price at arm.com>
> Cc: Alyssa Rosenzweig <alyssa.rosenzweig at collabora.com>
> Cc: David Airlie <airlied at linux.ie>
> Cc: Daniel Vetter <daniel at ffwll.ch>
> Signed-off-by: Rob Herring <robh at kernel.org>

Reviewed-by: Steven Price <steven.price at arm.com>

Although it might be worth trying to capture the justification about 
this in a comment somewhere - there's been a fair bit of discussion 
about this...

Steve

> ---
> v2: new patch
> 
>   drivers/gpu/drm/panfrost/panfrost_mmu.c | 6 +-----
>   1 file changed, 1 insertion(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> index ccf671a9c3fb..9f85275a896c 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
> @@ -328,11 +328,7 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo)
>   }
>   
>   static void mmu_tlb_inv_context_s1(void *cookie)
> -{
> -	struct panfrost_file_priv *priv = cookie;
> -
> -	mmu_hw_do_operation(priv->pfdev, &priv->mmu, 0, ~0UL, AS_COMMAND_FLUSH_MEM);
> -}
> +{}
>   
>   static void mmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
>   				     size_t granule, bool leaf, void *cookie)
>