[PATCH 2/4] drm/radeon: convert fence to uint64_t

[Michel Dänzer]

On Mit, 2012-05-02 at 16:20 -0400, j.glisse at gmail.com wrote: 
> From: Jerome Glisse <jglisse at redhat.com>
> 
> This convert fence to use uint64_t sequence number intention is
> to use the fact that uin64_t is big enough that we don't need to
> care about wrap around.
> 
> Tested with and without writeback using 0xFFFFF000 as initial
> fence sequence and thus allowing to test the wrap around from
> 32bits to 64bits.
> 
> Signed-off-by: Jerome Glisse <jglisse at redhat.com>

[...]

> diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c
> index 7733429..6da1535 100644
> --- a/drivers/gpu/drm/radeon/radeon_fence.c
> +++ b/drivers/gpu/drm/radeon/radeon_fence.c
> @@ -386,9 +388,9 @@ int radeon_fence_driver_start_ring(struct radeon_device *rdev, int ring)
>  			rdev->fence_drv[ring].scratch_reg -
>  			rdev->scratch.reg_base;
>  	}
> -	rdev->fence_drv[ring].cpu_addr = &rdev->wb.wb[index/4];
> +	rdev->fence_drv[ring].cpu_addr = (u64*)&rdev->wb.wb[index/4];

Might want to ensure cpu_addr is 64 bit aligned, or there might be
trouble on some architectures.


With this change, Cayman cards will already use six scratch registers
for the rings. It won't be possible to extend this scheme for even one
additional ring, will it?


-- 
Earthling Michel Dänzer           |                   http://www.amd.com
Libre software enthusiast         |          Debian, X and DRI developer