linux_dsm_epyc7002/include/asm-sh/atomic-llsc.h
Paul Mundt ec723fbe7e sh: Split out atomic ops logically.
We have a few different ways to do the atomic operations, so split
them out in to different headers rather than bloating atomic.h.
Kernelspace gUSA will take this up to a third implementation.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-12-12 08:42:08 +09:00

108 lines
2.1 KiB
C

#ifndef __ASM_SH_ATOMIC_LLSC_H
#define __ASM_SH_ATOMIC_LLSC_H
/*
* To get proper branch prediction for the main line, we must branch
* forward to code at the end of this object's .text section, then
* branch back to restart the operation.
*/
static inline void atomic_add(int i, atomic_t *v)
{
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_add \n"
" add %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
: "=&z" (tmp)
: "r" (i), "r" (&v->counter)
: "t");
}
static inline void atomic_sub(int i, atomic_t *v)
{
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_sub \n"
" sub %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
: "=&z" (tmp)
: "r" (i), "r" (&v->counter)
: "t");
}
/*
* SH-4A note:
*
* We basically get atomic_xxx_return() for free compared with
* atomic_xxx(). movli.l/movco.l require r0 due to the instruction
* encoding, so the retval is automatically set without having to
* do any special work.
*/
static inline int atomic_add_return(int i, atomic_t *v)
{
unsigned long temp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_add_return \n"
" add %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
" synco \n"
: "=&z" (temp)
: "r" (i), "r" (&v->counter)
: "t");
return temp;
}
static inline int atomic_sub_return(int i, atomic_t *v)
{
unsigned long temp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_sub_return \n"
" sub %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
" synco \n"
: "=&z" (temp)
: "r" (i), "r" (&v->counter)
: "t");
return temp;
}
static inline void atomic_clear_mask(unsigned int mask, atomic_t *v)
{
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_clear_mask \n"
" and %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
: "=&z" (tmp)
: "r" (~mask), "r" (&v->counter)
: "t");
}
static inline void atomic_set_mask(unsigned int mask, atomic_t *v)
{
unsigned long tmp;
__asm__ __volatile__ (
"1: movli.l @%2, %0 ! atomic_set_mask \n"
" or %1, %0 \n"
" movco.l %0, @%2 \n"
" bf 1b \n"
: "=&z" (tmp)
: "r" (mask), "r" (&v->counter)
: "t");
}
#endif /* __ASM_SH_ATOMIC_LLSC_H */