Re: [PATCH 1/7] drm/msm: Fix bv_fence being used as bv_rptr

[Konrad Dybcio <konradybcio@kernel.org>]

On 15.08.2024 8:26 PM, Antonino Maniscalco wrote:
> The bv_fence field of rbmemptrs was being used incorrectly as the BV
> rptr shadow pointer in some places.
> 
> Add a bv_rptr field and change the code to use that instead.
> 
> Signed-off-by: Antonino Maniscalco <antomani103@gmail.com>
> ---
>  drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 2 +-
>  drivers/gpu/drm/msm/msm_ringbuffer.h  | 1 +
>  2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> index bcaec86ac67a..32a4faa93d7f 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> @@ -1132,7 +1132,7 @@ static int hw_init(struct msm_gpu *gpu)
>  	/* ..which means "always" on A7xx, also for BV shadow */
>  	if (adreno_is_a7xx(adreno_gpu)) {
>  		gpu_write64(gpu, REG_A7XX_CP_BV_RB_RPTR_ADDR,
> -			    rbmemptr(gpu->rb[0], bv_fence));
> +			    rbmemptr(gpu->rb[0], bv_rptr));
>  	}
>  
>  	/* Always come up on rb 0 */
> diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.h b/drivers/gpu/drm/msm/msm_ringbuffer.h
> index 0d6beb8cd39a..40791b2ade46 100644
> --- a/drivers/gpu/drm/msm/msm_ringbuffer.h
> +++ b/drivers/gpu/drm/msm/msm_ringbuffer.h
> @@ -31,6 +31,7 @@ struct msm_rbmemptrs {
>  	volatile uint32_t rptr;
>  	volatile uint32_t fence;
>  	/* Introduced on A7xx */
> +	volatile uint32_t bv_rptr;

This is never initialized or assigned any value, no?

Konrad