diff options
| -rw-r--r-- | arch/riscv/include/asm/cmpxchg.h | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/cmpxchg.h b/arch/riscv/include/asm/cmpxchg.h index e3e0ac7ba061..ac9d0eeb74e6 100644 --- a/arch/riscv/include/asm/cmpxchg.h +++ b/arch/riscv/include/asm/cmpxchg.h @@ -72,6 +72,35 @@ * indicated by comparing RETURN with OLD. */ +#define __arch_cmpxchg_masked(sc_sfx, prepend, append, r, p, o, n) \ +({ \ + u32 *__ptr32b = (u32 *)((ulong)(p) & ~0x3); \ + ulong __s = ((ulong)(p) & (0x4 - sizeof(*p))) * BITS_PER_BYTE; \ + ulong __mask = GENMASK(((sizeof(*p)) * BITS_PER_BYTE) - 1, 0) \ + << __s; \ + ulong __newx = (ulong)(n) << __s; \ + ulong __oldx = (ulong)(o) << __s; \ + ulong __retx; \ + ulong __rc; \ + \ + __asm__ __volatile__ ( \ + prepend \ + "0: lr.w %0, %2\n" \ + " and %1, %0, %z5\n" \ + " bne %1, %z3, 1f\n" \ + " and %1, %0, %z6\n" \ + " or %1, %1, %z4\n" \ + " sc.w" sc_sfx " %1, %1, %2\n" \ + " bnez %1, 0b\n" \ + append \ + "1:\n" \ + : "=&r" (__retx), "=&r" (__rc), "+A" (*(__ptr32b)) \ + : "rJ" ((long)__oldx), "rJ" (__newx), \ + "rJ" (__mask), "rJ" (~__mask) \ + : "memory"); \ + \ + r = (__typeof__(*(p)))((__retx & __mask) >> __s); \ +}) #define __arch_cmpxchg(lr_sfx, sc_sfx, prepend, append, r, p, co, o, n) \ ({ \ @@ -98,6 +127,11 @@ __typeof__(*(__ptr)) __ret; \ \ switch (sizeof(*__ptr)) { \ + case 1: \ + case 2: \ + __arch_cmpxchg_masked(sc_sfx, prepend, append, \ + __ret, __ptr, __old, __new); \ + break; \ case 4: \ __arch_cmpxchg(".w", ".w" sc_sfx, prepend, append, \ __ret, __ptr, (long), __old, __new); \ |