[PATCH] drm/amd/amdgpu: Correct ring wptr address in debugfs

[Tom St Denis]

On 29/03/17 01:07 PM, Tom St Denis wrote:
> On gfx9 hardware the value is not wrapped and is a 64-bit value.  So
> we reduce it modulo the ring size.
>
> Signed-off-by: Tom St Denis <tom.stdenis at amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
> index ac0ce3f27f87..b6d2c0b2a501 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
> @@ -320,8 +320,8 @@ static ssize_t amdgpu_debugfs_ring_read(struct file *f, char __user *buf,
>
>  	if (*pos < 12) {
>  		early[0] = amdgpu_ring_get_rptr(ring);
> -		early[1] = amdgpu_ring_get_wptr(ring);
> -		early[2] = ring->wptr;
> +		early[1] = amdgpu_ring_get_wptr(ring) & ((ring->ring_size >> 2) - 1);
> +		early[2] = ring->wptr & ((ring->ring_size >> 2) - 1);
>  		for (i = *pos / 4; i < 3 && size; i++) {
>  			r = put_user(early[i], (uint32_t *)buf);
>  			if (r)
>

Particularly if reviewers could make sure I got the dword/byte 
conversion correct here.  It's my understanding ring_size is bytes and 
the get_*ptr() macros is in dwords right?

Tom