[PATCH] drm/panthor: Wait for _READY register when powering on

[Liviu Dudau]

On Mon, Jun 30, 2025 at 03:07:02PM +0100, Steven Price wrote:
> panthor_gpu_block_power_on() takes a register offset (rdy_reg) for the
> purpose of waiting for the power transition to complete. However, a
> copy/paste error converting to use the new 64 register functions
> switched it to using the pwrtrans_reg register instead. Fix the function
> to use the correct register.

Good catch!

> 
> Fixes: 4d230aa209ed ("drm/panthor: Add 64-bit and poll register accessors")
> Signed-off-by: Steven Price <steven.price at arm.com>

Reviewed-by: Liviu Dudau <liviu.dudau at arm.com>

Best regards,
Liviu

> ---
>  drivers/gpu/drm/panthor/panthor_gpu.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_gpu.c b/drivers/gpu/drm/panthor/panthor_gpu.c
> index 534735518824..cb7a335e07d7 100644
> --- a/drivers/gpu/drm/panthor/panthor_gpu.c
> +++ b/drivers/gpu/drm/panthor/panthor_gpu.c
> @@ -297,8 +297,9 @@ int panthor_gpu_block_power_on(struct panthor_device *ptdev,
>  
>  	gpu_write64(ptdev, pwron_reg, mask);
>  
> -	ret = gpu_read64_relaxed_poll_timeout(ptdev, pwrtrans_reg, val,
> -					      !(mask & val), 100, timeout_us);
> +	ret = gpu_read64_relaxed_poll_timeout(ptdev, rdy_reg, val,
> +					      (mask & val) == val,
> +					      100, timeout_us);
>  	if (ret) {
>  		drm_err(&ptdev->base, "timeout waiting on %s:%llx readiness",
>  			blk_name, mask);
> -- 
> 2.39.5
> 

-- 
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