In Linux these are meant to read a little-endian value and swap to the CPU endian.
In u-boot for m68k this is currently broken and prevents virtio-mmio from functioning. This change is only for classic m68k. Coldfire has read big-endian, no swap for these in u-boot and Linux and existing drivers probably depend on this. Tested-by: Angelo Dureghello <[email protected]> Reviewed-by: Simon Glass <[email protected]> Acked-by: Kuan-Wei Chiu <[email protected]> Acked-by: Angelo Dureghello <[email protected]> Signed-off-by: Daniel Palmer <[email protected]> --- arch/m68k/include/asm/io.h | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) diff --git a/arch/m68k/include/asm/io.h b/arch/m68k/include/asm/io.h index 35ad4a1c0444..2577081d8363 100644 --- a/arch/m68k/include/asm/io.h +++ b/arch/m68k/include/asm/io.h @@ -23,18 +23,27 @@ #define __raw_writew(w,addr) ((*(volatile u16 *) (addr)) = (w)) #define __raw_writel(l,addr) ((*(volatile u32 *) (addr)) = (l)) -#define readb(addr) in_8((volatile u8 *)(addr)) -#define writeb(b,addr) out_8((volatile u8 *)(addr), (b)) -#if !defined(__BIG_ENDIAN) -#define readw(addr) (*(volatile u16 *) (addr)) -#define readl(addr) (*(volatile u32 *) (addr)) -#define writew(b,addr) ((*(volatile u16 *) (addr)) = (b)) -#define writel(b,addr) ((*(volatile u32 *) (addr)) = (b)) +#define readb(addr) in_8((volatile u8 *)(addr)) +#define writeb(b, addr) out_8((volatile u8 *)(addr), (b)) +#ifdef CONFIG_M680x0 +/* + * For classic m68k these work the same way as Linux: + * Read a little endian value, swap to the CPU endian. + */ +#define readw(addr) in_le16((volatile u16 *)(addr)) +#define readl(addr) in_le32((volatile u32 *)(addr)) +#define writew(b, addr) out_le16((volatile u16 *)(addr), (b)) +#define writel(b, addr) out_le32((volatile u32 *)(addr), (b)) #else -#define readw(addr) in_be16((volatile u16 *)(addr)) -#define readl(addr) in_be32((volatile u32 *)(addr)) -#define writew(b,addr) out_be16((volatile u16 *)(addr),(b)) -#define writel(b,addr) out_be32((volatile u32 *)(addr),(b)) +/* + * For coldfire these read a big endian value and use it + * as-is. This means that for little endian devices on the + * bus like PCI device these won't work as expected currently. + */ +#define readw(addr) in_be16((volatile u16 *)(addr)) +#define readl(addr) in_be32((volatile u32 *)(addr)) +#define writew(b, addr) out_be16((volatile u16 *)(addr), (b)) +#define writel(b, addr) out_be32((volatile u32 *)(addr), (b)) #endif /* -- 2.53.0
