Re: [PATCH v9 7/8] crypto: caam: cleanup CONFIG_64BIT ifdefs when using io{read|write}64

[Horia Geantă]

On 1/3/2018 8:07 PM, Logan Gunthorpe wrote:
> Clean up the extra ifdefs which defined the wr_reg64 and rd_reg64
> functions in non-64bit cases in favour of the new common
> io-64-nonatomic-lo-hi header.
> 
> Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>
> Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> Cc: Horia Geantă <horia.geanta@xxxxxxx>
> Cc: Dan Douglass <dan.douglass@xxxxxxx>
> Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> ---
>  drivers/crypto/caam/regs.h | 26 +-------------------------
>  1 file changed, 1 insertion(+), 25 deletions(-)
> 
> diff --git a/drivers/crypto/caam/regs.h b/drivers/crypto/caam/regs.h
> index fee363865d88..ec6528e5ce9d 100644
> --- a/drivers/crypto/caam/regs.h
> +++ b/drivers/crypto/caam/regs.h
> @@ -10,7 +10,7 @@
>  
>  #include <linux/types.h>
>  #include <linux/bitops.h>
> -#include <linux/io.h>
> +#include <linux/io-64-nonatomic-hi-lo.h>
Typo: lo-hi should be used instead (see previous patch versions).

Please add in the commit message the explanation (which was there in v8 but
removed in v9):
To be consistent with CAAM engine HW spec: in case of 64-bit registers,
irrespective of device endianness, the lower address should be read from
/ written to first, followed by the upper address. Indeed the I/O
accessors in CAAM driver currently don't follow the spec, however this
is a good opportunity to fix the code.

>  
>  /*
>   * Architecture-specific register access methods
> @@ -136,7 +136,6 @@ static inline void clrsetbits_32(void __iomem *reg, u32 clear, u32 set)
>   *    base + 0x0000 : least-significant 32 bits
>   *    base + 0x0004 : most-significant 32 bits
>   */
> -#ifdef CONFIG_64BIT
>  static inline void wr_reg64(void __iomem *reg, u64 data)
>  {
>  	if (caam_little_end)
Since the 2 cases (32/64-bit) are merged, caam_imx should be accounted for the
logic to stay the same.

This means for e.g. for wr_reg64 (similar for rd_reg64):
static inline void wr_reg64(void __iomem *reg, u64 data)
{
	if (!caam_imx && caam_little_end)
		iowrite64(data, reg);
	else
		iowrite64be(data, reg);
}

Thanks,
Horia

> @@ -153,29 +152,6 @@ static inline u64 rd_reg64(void __iomem *reg)
>  		return ioread64be(reg);
>  }
>  
> -#else /* CONFIG_64BIT */
> -static inline void wr_reg64(void __iomem *reg, u64 data)
> -{
> -	if (!caam_imx && caam_little_end) {
> -		wr_reg32((u32 __iomem *)(reg) + 1, data >> 32);
> -		wr_reg32((u32 __iomem *)(reg), data);
> -	} else {
> -		wr_reg32((u32 __iomem *)(reg), data >> 32);
> -		wr_reg32((u32 __iomem *)(reg) + 1, data);
> -	}
> -}
> -
> -static inline u64 rd_reg64(void __iomem *reg)
> -{
> -	if (!caam_imx && caam_little_end)
> -		return ((u64)rd_reg32((u32 __iomem *)(reg) + 1) << 32 |
> -			(u64)rd_reg32((u32 __iomem *)(reg)));
> -
> -	return ((u64)rd_reg32((u32 __iomem *)(reg)) << 32 |
> -		(u64)rd_reg32((u32 __iomem *)(reg) + 1));
> -}
> -#endif /* CONFIG_64BIT  */
> -
>  static inline u64 cpu_to_caam_dma64(dma_addr_t value)
>  {
>  	if (caam_imx)
>