arch/csky/include/asm/checksum.h

Source file repositories/reference/linux-study-clean/arch/csky/include/asm/checksum.h

File Facts

System
Linux kernel
Corpus path
arch/csky/include/asm/checksum.h
Extension
.h
Size
944 bytes
Lines
50
Domain
Architecture Layer
Bucket
arch/csky
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef __ASM_CSKY_CHECKSUM_H
#define __ASM_CSKY_CHECKSUM_H

#include <linux/in6.h>
#include <asm/byteorder.h>

static inline __sum16 csum_fold(__wsum csum)
{
	u32 tmp;

	asm volatile(
	"mov	%1, %0\n"
	"rori	%0, 16\n"
	"addu	%0, %1\n"
	"lsri	%0, 16\n"
	: "=r"(csum), "=r"(tmp)
	: "0"(csum));

	return (__force __sum16) ~csum;
}
#define csum_fold csum_fold

static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
		unsigned short len, unsigned short proto, __wsum sum)
{
	asm volatile(
	"clrc\n"
	"addc    %0, %1\n"
	"addc    %0, %2\n"
	"addc    %0, %3\n"
	"inct    %0\n"
	: "=r"(sum)
	: "r"((__force u32)saddr), "r"((__force u32)daddr),
#ifdef __BIG_ENDIAN
	"r"(proto + len),
#else
	"r"((proto + len) << 8),
#endif
	"0" ((__force unsigned long)sum)
	: "cc");
	return sum;
}
#define csum_tcpudp_nofold csum_tcpudp_nofold

#include <asm-generic/checksum.h>

#endif /* __ASM_CSKY_CHECKSUM_H */

Annotation

Implementation Notes