#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: * r0 = address of first instruction after the atomic sequence * r1 = original stack pointer * r15 = -1 * length of atomic sequence in bytes */ #define GUSA_CLOBBERS "r0", "r1", "memory" #define GUSA_START(mem,old,nop) \ " .align 2\n" \ " mova 1f, r0\n" \ nop \ " mov r15, r1\n" \ " mov #(0f-1f), r15\n" \ "0: mov.l @" mem ", " old "\n" /* the target of mova must be 4 byte aligned, so we may need a nop */ #define GUSA_START_ODD(mem,old) GUSA_START(mem,old,"") #define GUSA_START_EVEN(mem,old) GUSA_START(mem,old,"\tnop\n") #define GUSA_END(mem,new) \ " mov.l " new ", @" mem "\n" \ "1: mov r1, r15\n" int __sh_cas(volatile int *p, int t, int 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__( GUSA_START_EVEN("%1", "%0") " cmp/eq %0, %2\n" " bf 1f\n" GUSA_END("%1", "%3") : "=&r"(old) : "r"(p), "r"(t), "r"(s) : GUSA_CLOBBERS, "t"); return old; } int __sh_swap(volatile int *x, int 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__( GUSA_START_EVEN("%1", "%0") GUSA_END("%1", "%2") : "=&r"(old) : "r"(x), "r"(v) : GUSA_CLOBBERS); return old; } int __sh_fetch_add(volatile int *x, int 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__( GUSA_START_EVEN("%2", "%0") " mov %0, %1\n" " add %3, %1\n" GUSA_END("%2", "%1") : "=&r"(old), "=&r"(dummy) : "r"(x), "r"(v) : GUSA_CLOBBERS); return old; } void __sh_store(volatile int *p, int 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"); } void __sh_and(volatile int *x, int 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__( GUSA_START_ODD("%1", "%0") " and %2, %0\n" GUSA_END("%1", "%0") : "=&r"(dummy) : "r"(x), "r"(v) : GUSA_CLOBBERS); } void __sh_or(volatile int *x, int 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__( GUSA_START_ODD("%1", "%0") " or %2, %0\n" GUSA_END("%1", "%0") : "=&r"(dummy) : "r"(x), "r"(v) : GUSA_CLOBBERS); } #endif