diff options
Diffstat (limited to 'arch/sh/src/atomic.c')
| -rw-r--r-- | arch/sh/src/atomic.c | 72 |
1 files changed, 64 insertions, 8 deletions
diff --git a/arch/sh/src/atomic.c b/arch/sh/src/atomic.c index f8c615f8..7fd73074 100644 --- a/arch/sh/src/atomic.c +++ b/arch/sh/src/atomic.c @@ -1,8 +1,26 @@ #ifndef __SH4A__ +#include "sh_atomic.h" #include "atomic.h" #include "libc.h" +static inline unsigned mask() +{ + unsigned sr; + __asm__ __volatile__ ( "\n" + " stc sr,r0 \n" + " mov r0,%0 \n" + " or #0xf0,r0 \n" + " ldc r0,sr \n" + : "=&r"(sr) : : "memory", "r0" ); + return sr; +} + +static inline void unmask(unsigned sr) +{ + __asm__ __volatile__ ( "ldc %0,sr" : : "r"(sr) : "memory" ); +} + /* gusa is a hack in the kernel which lets you create a sequence of instructions * which will be restarted if the process is preempted in the middle of the * sequence. It will do for implementing atomics on non-smp systems. ABI is: @@ -25,11 +43,17 @@ " mov.l " new ", @" mem "\n" \ "1: mov r1, r15\n" -#define CPU_HAS_LLSC 0x0040 - int __sh_cas(volatile int *p, int t, int s) { - if (__hwcap & CPU_HAS_LLSC) return __sh_cas_llsc(p, t, s); + if (__sh_atomic_model == SH_A_LLSC) return __sh_cas_llsc(p, t, s); + + if (__sh_atomic_model == SH_A_IMASK) { + unsigned sr = mask(); + int old = *p; + if (old==t) *p = s; + unmask(sr); + return old; + } int old; __asm__ __volatile__( @@ -43,7 +67,15 @@ int __sh_cas(volatile int *p, int t, int s) int __sh_swap(volatile int *x, int v) { - if (__hwcap & CPU_HAS_LLSC) return __sh_swap_llsc(x, v); + if (__sh_atomic_model == SH_A_LLSC) return __sh_swap_llsc(x, v); + + if (__sh_atomic_model == SH_A_IMASK) { + unsigned sr = mask(); + int old = *x; + *x = v; + unmask(sr); + return old; + } int old; __asm__ __volatile__( @@ -55,7 +87,15 @@ int __sh_swap(volatile int *x, int v) int __sh_fetch_add(volatile int *x, int v) { - if (__hwcap & CPU_HAS_LLSC) return __sh_fetch_add_llsc(x, v); + if (__sh_atomic_model == SH_A_LLSC) return __sh_fetch_add_llsc(x, v); + + if (__sh_atomic_model == SH_A_IMASK) { + unsigned sr = mask(); + int old = *x; + *x = old + v; + unmask(sr); + return old; + } int old, dummy; __asm__ __volatile__( @@ -69,7 +109,7 @@ int __sh_fetch_add(volatile int *x, int v) void __sh_store(volatile int *p, int x) { - if (__hwcap & CPU_HAS_LLSC) return __sh_store_llsc(p, x); + if (__sh_atomic_model == SH_A_LLSC) return __sh_store_llsc(p, x); __asm__ __volatile__( " mov.l %1, @%0\n" : : "r"(p), "r"(x) : "memory"); @@ -77,7 +117,15 @@ void __sh_store(volatile int *p, int x) void __sh_and(volatile int *x, int v) { - if (__hwcap & CPU_HAS_LLSC) return __sh_and_llsc(x, v); + if (__sh_atomic_model == SH_A_LLSC) return __sh_and_llsc(x, v); + + if (__sh_atomic_model == SH_A_IMASK) { + unsigned sr = mask(); + int old = *x; + *x = old & v; + unmask(sr); + return; + } int dummy; __asm__ __volatile__( @@ -89,7 +137,15 @@ void __sh_and(volatile int *x, int v) void __sh_or(volatile int *x, int v) { - if (__hwcap & CPU_HAS_LLSC) return __sh_or_llsc(x, v); + if (__sh_atomic_model == SH_A_LLSC) return __sh_or_llsc(x, v); + + if (__sh_atomic_model == SH_A_IMASK) { + unsigned sr = mask(); + int old = *x; + *x = old | v; + unmask(sr); + return; + } int dummy; __asm__ __volatile__( |