Re: [PATCH] media: staging: ipu7: cleanup register names and suffixes

[Dan Carpenter]

On Wed, Apr 15, 2026 at 09:02:05AM +0200, deep@xxxxxxxxxxxxxxxxxx wrote:
> From: Kenet Jovan Sokoli <deep@xxxxxxxxxxxxxxxxxx>
> 
> Rename BUTTRESS_ registers to include IPU7_ prefix and
> remove unnecessary U suffixes from numeric constants
> for consistency.
> 

The the renames and changing the types from u32 to int should probably
be done in separate patches.

You need to be a bit careful with changing types.  Generally, you should
use unsigned types for bitwise operations.  So the _MASK variables should
be unsigned.

> diff --git a/drivers/staging/media/ipu7/ipu7-mmu.c b/drivers/staging/media/ipu7/ipu7-mmu.c
> index 6ded07ccd780..c5f83023ddbd 100644
> --- a/drivers/staging/media/ipu7/ipu7-mmu.c
> +++ b/drivers/staging/media/ipu7/ipu7-mmu.c
> @@ -33,16 +33,16 @@
>  
>  #define ISP_PAGE_SHIFT		12
>  #define ISP_PAGE_SIZE		BIT(ISP_PAGE_SHIFT)
> -#define ISP_PAGE_MASK		(~(ISP_PAGE_SIZE - 1U))
> +#define IPU7_ISP_PAGE_MASK		(~(ISP_PAGE_SIZE - 1))
>  
>  #define ISP_L1PT_SHIFT		22
> -#define ISP_L1PT_MASK		(~((1U << ISP_L1PT_SHIFT) - 1))
> +#define IPU7_ISP_L1PT_MASK		(~((1 << ISP_L1PT_SHIFT) - 1))
>  
>  #define ISP_L2PT_SHIFT		12
> -#define ISP_L2PT_MASK		(~(ISP_L1PT_MASK | (~(ISP_PAGE_MASK))))
> +#define ISP_L2PT_MASK		(~(IPU7_ISP_L1PT_MASK | (~(IPU7_ISP_PAGE_MASK))))

In the original code this was 0x3ff000 but now, because of sign
extension, it is 0xffffffff003ff000.  Does it make a difference?
I don't know.  But it makes me uncomfortable to see all these changes
thrown together like this where it's so hard to spot.

regards,
dan carpenter