Re: [PATCH 2/8] drm/amdgpu: fix 32-bit build warning

[Oded Gabbay]

On Fri, May 25, 2018 at 6:50 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
> Casting a pointer to a 64-bit type causes a warning on 32-bit targets:
>
> drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gfx_v9.c:473:24: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>           lower_32_bits((uint64_t)wptr));
>                         ^
> drivers/gpu/drm/amd/amdgpu/amdgpu.h:1701:53: note: in definition of macro 'WREG32'
>  #define WREG32(reg, v) amdgpu_mm_wreg(adev, (reg), (v), 0)
>                                                      ^
> drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gfx_v9.c:473:10: note: in expansion of macro 'lower_32_bits'
>           lower_32_bits((uint64_t)wptr));
>           ^~~~~~~~~~~~~
>
> The correct method is to cast to 'uintptr_t'.
>
> Fixes: d5a114a6c5f7 ("drm/amdgpu: Add GFXv9 kfd2kgd interface functions")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gfx_v9.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gfx_v9.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gfx_v9.c
> index 8f37991df61b..f0c0d3953f69 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gfx_v9.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gfx_v9.c
> @@ -470,9 +470,9 @@ static int kgd_hqd_load(struct kgd_dev *kgd, void *mqd, uint32_t pipe_id,
>                 WREG32(SOC15_REG_OFFSET(GC, 0, mmCP_HQD_PQ_WPTR_HI),
>                        upper_32_bits(guessed_wptr));
>                 WREG32(SOC15_REG_OFFSET(GC, 0, mmCP_HQD_PQ_WPTR_POLL_ADDR),
> -                      lower_32_bits((uint64_t)wptr));
> +                      lower_32_bits((uintptr_t)wptr));
>                 WREG32(SOC15_REG_OFFSET(GC, 0, mmCP_HQD_PQ_WPTR_POLL_ADDR_HI),
> -                      upper_32_bits((uint64_t)wptr));
> +                      upper_32_bits((uintptr_t)wptr));
>                 WREG32(SOC15_REG_OFFSET(GC, 0, mmCP_PQ_WPTR_POLL_CNTL1),
>                        get_queue_mask(adev, pipe_id, queue_id));
>         }
> --
> 2.9.0
>

There is a change scheduled for the next merge window that will cause
this file to not build anymore on 32-bit targets (because the amdkfd
driver is not supported on 32 bit targets).

Never the less I'm taking the patch for good measure.

This patch is:
Reviewed-by: Oded Gabbay <oded.gabbay@xxxxxxxxx>