Re: [PATCH v2 3/3] crypto: caam: cleanup CONFIG_64BIT ifdefs when using io{read|write}64

[Arnd Bergmann <arnd@arndb.de>]

On Wed, Jun 28, 2017 at 1:02 AM, Logan Gunthorpe <logang@deltatee.com> wrote:
>  #include <linux/types.h>
>  #include <linux/bitops.h>
> -#include <linux/io.h>
> +#include <linux/io-64-nonatomic-hi-lo.h>

Here you include the hi-lo variant unconditionally.

> -#else /* CONFIG_64BIT */
> -static inline void wr_reg64(void __iomem *reg, u64 data)
> -{
> -#ifndef CONFIG_CRYPTO_DEV_FSL_CAAM_IMX
> -       if (caam_little_end) {
> -               wr_reg32((u32 __iomem *)(reg) + 1, data >> 32);
> -               wr_reg32((u32 __iomem *)(reg), data);
> -       } else
>  #endif
> -       {
> -               wr_reg32((u32 __iomem *)(reg), data >> 32);
> -               wr_reg32((u32 __iomem *)(reg) + 1, data);
> -       }
> +               iowrite64be(data, reg);
>  }

However, the #else path here uses lo-hi instead. I guess we have
to decide how to define iowrite64be_lo_hi() first: it could
either byteswap the 64-bit value first, then write the two halves,
or it could write the two halves, doing a 32-bit byte swap on
each.

       Arnd