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Diffstat (limited to 'arch/riscv/include/asm/cmpxchg.h')
-rw-r--r--arch/riscv/include/asm/cmpxchg.h40
1 files changed, 36 insertions, 4 deletions
diff --git a/arch/riscv/include/asm/cmpxchg.h b/arch/riscv/include/asm/cmpxchg.h
index 4cadc56220fe..2ec119eb147b 100644
--- a/arch/riscv/include/asm/cmpxchg.h
+++ b/arch/riscv/include/asm/cmpxchg.h
@@ -231,7 +231,7 @@
__arch_cmpxchg(".w", ".w" sc_sfx, ".w" cas_sfx, \
sc_prepend, sc_append, \
cas_prepend, cas_append, \
- __ret, __ptr, (long), __old, __new); \
+ __ret, __ptr, (long)(int)(long), __old, __new); \
break; \
case 8: \
__arch_cmpxchg(".d", ".d" sc_sfx, ".d" cas_sfx, \
@@ -365,16 +365,48 @@ static __always_inline void __cmpwait(volatile void *ptr,
{
unsigned long tmp;
+ u32 *__ptr32b;
+ ulong __s, __val, __mask;
+
asm goto(ALTERNATIVE("j %l[no_zawrs]", "nop",
0, RISCV_ISA_EXT_ZAWRS, 1)
: : : : no_zawrs);
switch (size) {
case 1:
- fallthrough;
+ __ptr32b = (u32 *)((ulong)(ptr) & ~0x3);
+ __s = ((ulong)(ptr) & 0x3) * BITS_PER_BYTE;
+ __val = val << __s;
+ __mask = 0xff << __s;
+
+ asm volatile(
+ " lr.w %0, %1\n"
+ " and %0, %0, %3\n"
+ " xor %0, %0, %2\n"
+ " bnez %0, 1f\n"
+ ZAWRS_WRS_NTO "\n"
+ "1:"
+ : "=&r" (tmp), "+A" (*(__ptr32b))
+ : "r" (__val), "r" (__mask)
+ : "memory");
+ break;
case 2:
- /* RISC-V doesn't have lr instructions on byte and half-word. */
- goto no_zawrs;
+ __ptr32b = (u32 *)((ulong)(ptr) & ~0x3);
+ __s = ((ulong)(ptr) & 0x2) * BITS_PER_BYTE;
+ __val = val << __s;
+ __mask = 0xffff << __s;
+
+ asm volatile(
+ " lr.w %0, %1\n"
+ " and %0, %0, %3\n"
+ " xor %0, %0, %2\n"
+ " bnez %0, 1f\n"
+ ZAWRS_WRS_NTO "\n"
+ "1:"
+ : "=&r" (tmp), "+A" (*(__ptr32b))
+ : "r" (__val), "r" (__mask)
+ : "memory");
+ break;
case 4:
asm volatile(
" lr.w %0, %1\n"