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

From: Arnd Bergmann
Date: Wed Jun 28 2017 - 06:21:01 EST


On Wed, Jun 28, 2017 at 1:02 AM, Logan Gunthorpe <logang@xxxxxxxxxxxx> 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