linux_dsm_epyc7002/include/asm-sh/cmpxchg-grb.h
Stuart Menefy 1efe4ce3ca sh: GUSA atomic rollback support.
This implements kernel-level atomic rollback built on top of gUSA,
as an alternative non-IRQ based atomicity method. This is generally
a faster method for platforms that are lacking the LL/SC pairs that
SH-4A and later use, and is only supportable on legacy cores.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-01-28 13:18:58 +09:00

71 lines
2.0 KiB
C

#ifndef __ASM_SH_CMPXCHG_GRB_H
#define __ASM_SH_CMPXCHG_GRB_H
static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
{
unsigned long retval;
__asm__ __volatile__ (
" .align 2 \n\t"
" mova 1f, r0 \n\t" /* r0 = end point */
" nop \n\t"
" mov r15, r1 \n\t" /* r1 = saved sp */
" mov #-4, r15 \n\t" /* LOGIN */
" mov.l @%1, %0 \n\t" /* load old value */
" mov.l %2, @%1 \n\t" /* store new value */
"1: mov r1, r15 \n\t" /* LOGOUT */
: "=&r" (retval),
"+r" (m)
: "r" (val)
: "memory", "r0", "r1");
return retval;
}
static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
{
unsigned long retval;
__asm__ __volatile__ (
" .align 2 \n\t"
" mova 1f, r0 \n\t" /* r0 = end point */
" mov r15, r1 \n\t" /* r1 = saved sp */
" mov #-6, r15 \n\t" /* LOGIN */
" mov.b @%1, %0 \n\t" /* load old value */
" extu.b %0, %0 \n\t" /* extend as unsigned */
" mov.b %2, @%1 \n\t" /* store new value */
"1: mov r1, r15 \n\t" /* LOGOUT */
: "=&r" (retval),
"+r" (m)
: "r" (val)
: "memory" , "r0", "r1");
return retval;
}
static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
unsigned long new)
{
unsigned long retval;
__asm__ __volatile__ (
" .align 2 \n\t"
" mova 1f, r0 \n\t" /* r0 = end point */
" nop \n\t"
" mov r15, r1 \n\t" /* r1 = saved sp */
" mov #-8, r15 \n\t" /* LOGIN */
" mov.l @%1, %0 \n\t" /* load old value */
" cmp/eq %0, %2 \n\t"
" bf 1f \n\t" /* if not equal */
" mov.l %2, @%1 \n\t" /* store new value */
"1: mov r1, r15 \n\t" /* LOGOUT */
: "=&r" (retval),
"+r" (m)
: "r" (new)
: "memory" , "r0", "r1", "t");
return retval;
}
#endif /* __ASM_SH_CMPXCHG_GRB_H */