Commit 0d5bbe0b authored by Paul Mundt's avatar Paul Mundt

sh: Provide optimized non-atomic bitops for SH-2A.

This ties in the new SH-2A 32-bit non-atomic bitops.
Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent 8bcc5c1c
#ifndef __ASM_SH_BITOPS_OP32_H
#define __ASM_SH_BITOPS_OP32_H
/*
* The bit modifying instructions on SH-2A are only capable of working
* with a 3-bit immediate, which signifies the shift position for the bit
* being worked on.
*/
#if defined(__BIG_ENDIAN)
#define BITOP_LE_SWIZZLE ((BITS_PER_LONG-1) & ~0x7)
#define BYTE_NUMBER(nr) ((nr ^ BITOP_LE_SWIZZLE) / BITS_PER_BYTE)
#define BYTE_OFFSET(nr) ((nr ^ BITOP_LE_SWIZZLE) % BITS_PER_BYTE)
#else
#define BYTE_NUMBER(nr) ((nr) / BITS_PER_BYTE)
#define BYTE_OFFSET(nr) ((nr) % BITS_PER_BYTE)
#endif
#define IS_IMMEDIATE(nr) (__builtin_constant_p(nr))
static inline void __set_bit(int nr, volatile unsigned long *addr)
{
if (IS_IMMEDIATE(nr)) {
__asm__ __volatile__ (
"bset.b %1, @(%O2,%0) ! __set_bit\n\t"
: "+r" (addr)
: "i" (BYTE_OFFSET(nr)), "i" (BYTE_NUMBER(nr))
: "t", "memory"
);
} else {
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
*p |= mask;
}
}
static inline void __clear_bit(int nr, volatile unsigned long *addr)
{
if (IS_IMMEDIATE(nr)) {
__asm__ __volatile__ (
"bclr.b %1, @(%O2,%0) ! __clear_bit\n\t"
: "+r" (addr)
: "i" (BYTE_OFFSET(nr)),
"i" (BYTE_NUMBER(nr))
: "t", "memory"
);
} else {
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
*p &= ~mask;
}
}
/**
* __change_bit - Toggle a bit in memory
* @nr: the bit to change
* @addr: the address to start counting from
*
* Unlike change_bit(), this function is non-atomic and may be reordered.
* If it's called on the same region of memory simultaneously, the effect
* may be that only one operation succeeds.
*/
static inline void __change_bit(int nr, volatile unsigned long *addr)
{
if (IS_IMMEDIATE(nr)) {
__asm__ __volatile__ (
"bxor.b %1, @(%O2,%0) ! __change_bit\n\t"
: "+r" (addr)
: "i" (BYTE_OFFSET(nr)),
"i" (BYTE_NUMBER(nr))
: "t", "memory"
);
} else {
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
*p ^= mask;
}
}
/**
* __test_and_set_bit - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is non-atomic and can be reordered.
* If two examples of this operation race, one can appear to succeed
* but actually fail. You must protect multiple accesses with a lock.
*/
static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
unsigned long old = *p;
*p = old | mask;
return (old & mask) != 0;
}
/**
* __test_and_clear_bit - Clear a bit and return its old value
* @nr: Bit to clear
* @addr: Address to count from
*
* This operation is non-atomic and can be reordered.
* If two examples of this operation race, one can appear to succeed
* but actually fail. You must protect multiple accesses with a lock.
*/
static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
unsigned long old = *p;
*p = old & ~mask;
return (old & mask) != 0;
}
/* WARNING: non atomic and it can be reordered! */
static inline int __test_and_change_bit(int nr,
volatile unsigned long *addr)
{
unsigned long mask = BIT_MASK(nr);
unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
unsigned long old = *p;
*p = old ^ mask;
return (old & mask) != 0;
}
/**
* test_bit - Determine whether a bit is set
* @nr: bit number to test
* @addr: Address to start counting from
*/
static inline int test_bit(int nr, const volatile unsigned long *addr)
{
return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
}
#endif /* __ASM_SH_BITOPS_OP32_H */
...@@ -13,6 +13,9 @@ ...@@ -13,6 +13,9 @@
#ifdef CONFIG_GUSA_RB #ifdef CONFIG_GUSA_RB
#include <asm/bitops-grb.h> #include <asm/bitops-grb.h>
#elif defined(CONFIG_CPU_SH2A)
#include <asm-generic/bitops/atomic.h>
#include <asm/bitops-op32.h>
#elif defined(CONFIG_CPU_SH4A) #elif defined(CONFIG_CPU_SH4A)
#include <asm/bitops-llsc.h> #include <asm/bitops-llsc.h>
#else #else
......
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