[PATCH v2 2/5] m68k: Fix writew(), writel(), readw(), readl() endianness

Daniel Palmer daniel at thingy.jp
Mon Apr 6 16:24:08 CEST 2026


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 borken and prevents
virtio-mmio from functioning.

Signed-off-by: Daniel Palmer <daniel at thingy.jp>
---
 arch/m68k/include/asm/io.h | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/arch/m68k/include/asm/io.h b/arch/m68k/include/asm/io.h
index 35ad4a1c0444..f4877b0446cf 100644
--- a/arch/m68k/include/asm/io.h
+++ b/arch/m68k/include/asm/io.h
@@ -24,18 +24,11 @@
 #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))
-#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))
-#endif
+#define writeb(b, addr)		out_8((volatile u8 *)(addr), (b))
+#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))
 
 /*
  * The insw/outsw/insl/outsl macros don't do byte-swapping.
-- 
2.51.0



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