Signed-off-by: Oleksii Kurochko <oleksii.kuroc...@gmail.com> --- Changes in V2: - update the comment at the top of the header. - change xen/lib.h to xen/bug.h. - sort inclusion of headers properly. --- xen/arch/riscv/include/asm/cmpxchg.h | 379 +++++++++++++++++++++++++++ 1 file changed, 379 insertions(+) create mode 100644 xen/arch/riscv/include/asm/cmpxchg.h
diff --git a/xen/arch/riscv/include/asm/cmpxchg.h b/xen/arch/riscv/include/asm/cmpxchg.h new file mode 100644 index 0000000000..c535bc9660 --- /dev/null +++ b/xen/arch/riscv/include/asm/cmpxchg.h @@ -0,0 +1,379 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Taken and modified from Linux. + * + * Copyright (C) 2014 Regents of the University of California + */ + +#ifndef _ASM_RISCV_CMPXCHG_H +#define _ASM_RISCV_CMPXCHG_H + +#include <xen/bug.h> + +#include <asm/fence.h> +#include <asm/system.h> + +#define __xchg_relaxed(ptr, new, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(new) __new = (new); \ + __typeof__(*(ptr)) __ret; \ + switch (size) { \ + case 4: \ + __asm__ __volatile__ ( \ + " amoswap.w %0, %2, %1\n" \ + : "=r" (__ret), "+A" (*__ptr) \ + : "r" (__new) \ + : "memory"); \ + break; \ + case 8: \ + __asm__ __volatile__ ( \ + " amoswap.d %0, %2, %1\n" \ + : "=r" (__ret), "+A" (*__ptr) \ + : "r" (__new) \ + : "memory"); \ + break; \ + default: \ + ASSERT_UNREACHABLE(); \ + } \ + __ret; \ +}) + +#define xchg_relaxed(ptr, x) \ +({ \ + __typeof__(*(ptr)) _x_ = (x); \ + (__typeof__(*(ptr))) __xchg_relaxed((ptr), \ + _x_, sizeof(*(ptr))); \ +}) + +#define __xchg_acquire(ptr, new, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(new) __new = (new); \ + __typeof__(*(ptr)) __ret; \ + switch (size) { \ + case 4: \ + __asm__ __volatile__ ( \ + " amoswap.w %0, %2, %1\n" \ + RISCV_ACQUIRE_BARRIER \ + : "=r" (__ret), "+A" (*__ptr) \ + : "r" (__new) \ + : "memory"); \ + break; \ + case 8: \ + __asm__ __volatile__ ( \ + " amoswap.d %0, %2, %1\n" \ + RISCV_ACQUIRE_BARRIER \ + : "=r" (__ret), "+A" (*__ptr) \ + : "r" (__new) \ + : "memory"); \ + break; \ + default: \ + ASSERT_UNREACHABLE(); \ + } \ + __ret; \ +}) + +#define xchg_acquire(ptr, x) \ +({ \ + __typeof__(*(ptr)) _x_ = (x); \ + (__typeof__(*(ptr))) __xchg_acquire((ptr), \ + _x_, sizeof(*(ptr))); \ +}) + +#define __xchg_release(ptr, new, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(new) __new = (new); \ + __typeof__(*(ptr)) __ret; \ + switch (size) { \ + case 4: \ + __asm__ __volatile__ ( \ + RISCV_RELEASE_BARRIER \ + " amoswap.w %0, %2, %1\n" \ + : "=r" (__ret), "+A" (*__ptr) \ + : "r" (__new) \ + : "memory"); \ + break; \ + case 8: \ + __asm__ __volatile__ ( \ + RISCV_RELEASE_BARRIER \ + " amoswap.d %0, %2, %1\n" \ + : "=r" (__ret), "+A" (*__ptr) \ + : "r" (__new) \ + : "memory"); \ + break; \ + default: \ + ASSERT_UNREACHABLE(); \ + } \ + __ret; \ +}) + +#define xchg_release(ptr, x) \ +({ \ + __typeof__(*(ptr)) _x_ = (x); \ + (__typeof__(*(ptr))) __xchg_release((ptr), \ + _x_, sizeof(*(ptr))); \ +}) + +#define __xchg(ptr, new, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(new) __new = (new); \ + __typeof__(*(ptr)) __ret; \ + switch (size) { \ + case 4: \ + __asm__ __volatile__ ( \ + " amoswap.w.aqrl %0, %2, %1\n" \ + : "=r" (__ret), "+A" (*__ptr) \ + : "r" (__new) \ + : "memory"); \ + break; \ + case 8: \ + __asm__ __volatile__ ( \ + " amoswap.d.aqrl %0, %2, %1\n" \ + : "=r" (__ret), "+A" (*__ptr) \ + : "r" (__new) \ + : "memory"); \ + break; \ + default: \ + __ret = 0; \ + ASSERT_UNREACHABLE(); \ + } \ + __ret; \ +}) + +#define xchg(ptr, x) \ +({ \ + __typeof__(*(ptr)) _x_ = (x); \ + (__typeof__(*(ptr))) __xchg((ptr), _x_, sizeof(*(ptr))); \ +}) + +#define xchg32(ptr, x) \ +({ \ + BUILD_BUG_ON(sizeof(*(ptr)) != 4); \ + xchg((ptr), (x)); \ +}) + +#define xchg64(ptr, x) \ +({ \ + BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ + xchg((ptr), (x)); \ +}) + +/* + * Atomic compare and exchange. Compare OLD with MEM, if identical, + * store NEW in MEM. Return the initial value in MEM. Success is + * indicated by comparing RETURN with OLD. + */ +#define __cmpxchg_relaxed(ptr, old, new, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(*(ptr)) __old = (old); \ + __typeof__(*(ptr)) __new = (new); \ + __typeof__(*(ptr)) __ret; \ + register unsigned int __rc; \ + switch (size) { \ + case 4: \ + __asm__ __volatile__ ( \ + "0: lr.w %0, %2\n" \ + " bne %0, %z3, 1f\n" \ + " sc.w %1, %z4, %2\n" \ + " bnez %1, 0b\n" \ + "1:\n" \ + : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ + : "rJ" (__old), "rJ" (__new) \ + : "memory"); \ + break; \ + case 8: \ + __asm__ __volatile__ ( \ + "0: lr.d %0, %2\n" \ + " bne %0, %z3, 1f\n" \ + " sc.d %1, %z4, %2\n" \ + " bnez %1, 0b\n" \ + "1:\n" \ + : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ + : "rJ" (__old), "rJ" (__new) \ + : "memory"); \ + break; \ + default: \ + ASSERT_UNREACHABLE(); \ + } \ + __ret; \ +}) + +#define cmpxchg_relaxed(ptr, o, n) \ +({ \ + __typeof__(*(ptr)) _o_ = (o); \ + __typeof__(*(ptr)) _n_ = (n); \ + (__typeof__(*(ptr))) __cmpxchg_relaxed((ptr), \ + _o_, _n_, sizeof(*(ptr))); \ +}) + +#define __cmpxchg_acquire(ptr, old, new, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(*(ptr)) __old = (old); \ + __typeof__(*(ptr)) __new = (new); \ + __typeof__(*(ptr)) __ret; \ + register unsigned int __rc; \ + switch (size) { \ + case 4: \ + __asm__ __volatile__ ( \ + "0: lr.w %0, %2\n" \ + " bne %0, %z3, 1f\n" \ + " sc.w %1, %z4, %2\n" \ + " bnez %1, 0b\n" \ + RISCV_ACQUIRE_BARRIER \ + "1:\n" \ + : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ + : "rJ" (__old), "rJ" (__new) \ + : "memory"); \ + break; \ + case 8: \ + __asm__ __volatile__ ( \ + "0: lr.d %0, %2\n" \ + " bne %0, %z3, 1f\n" \ + " sc.d %1, %z4, %2\n" \ + " bnez %1, 0b\n" \ + RISCV_ACQUIRE_BARRIER \ + "1:\n" \ + : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ + : "rJ" (__old), "rJ" (__new) \ + : "memory"); \ + break; \ + default: \ + ASSERT_UNREACHABLE(); \ + } \ + __ret; \ +}) + +#define cmpxchg_acquire(ptr, o, n) \ +({ \ + __typeof__(*(ptr)) _o_ = (o); \ + __typeof__(*(ptr)) _n_ = (n); \ + (__typeof__(*(ptr))) __cmpxchg_acquire((ptr), \ + _o_, _n_, sizeof(*(ptr))); \ +}) + +#define __cmpxchg_release(ptr, old, new, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(*(ptr)) __old = (old); \ + __typeof__(*(ptr)) __new = (new); \ + __typeof__(*(ptr)) __ret; \ + register unsigned int __rc; \ + switch (size) { \ + case 4: \ + __asm__ __volatile__ ( \ + RISCV_RELEASE_BARRIER \ + "0: lr.w %0, %2\n" \ + " bne %0, %z3, 1f\n" \ + " sc.w %1, %z4, %2\n" \ + " bnez %1, 0b\n" \ + "1:\n" \ + : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ + : "rJ" (__old), "rJ" (__new) \ + : "memory"); \ + break; \ + case 8: \ + __asm__ __volatile__ ( \ + RISCV_RELEASE_BARRIER \ + "0: lr.d %0, %2\n" \ + " bne %0, %z3, 1f\n" \ + " sc.d %1, %z4, %2\n" \ + " bnez %1, 0b\n" \ + "1:\n" \ + : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ + : "rJ" (__old), "rJ" (__new) \ + : "memory"); \ + break; \ + default: \ + ASSERT_UNREACHABLE(); \ + } \ + __ret; \ +}) + +#define cmpxchg_release(ptr, o, n) \ +({ \ + __typeof__(*(ptr)) _o_ = (o); \ + __typeof__(*(ptr)) _n_ = (n); \ + (__typeof__(*(ptr))) __cmpxchg_release((ptr), \ + _o_, _n_, sizeof(*(ptr))); \ +}) + +#define __cmpxchg(ptr, old, new, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(*(ptr)) __old = (__typeof__(*(ptr)))(old); \ + __typeof__(*(ptr)) __new = (__typeof__(*(ptr)))(new); \ + __typeof__(*(ptr)) __ret; \ + register unsigned int __rc; \ + switch (size) { \ + case 4: \ + __asm__ __volatile__ ( \ + "0: lr.w %0, %2\n" \ + " bne %0, %z3, 1f\n" \ + " sc.w.rl %1, %z4, %2\n" \ + " bnez %1, 0b\n" \ + " fence rw, rw\n" \ + "1:\n" \ + : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ + : "rJ" (__old), "rJ" (__new) \ + : "memory"); \ + break; \ + case 8: \ + __asm__ __volatile__ ( \ + "0: lr.d %0, %2\n" \ + " bne %0, %z3, 1f\n" \ + " sc.d.rl %1, %z4, %2\n" \ + " bnez %1, 0b\n" \ + " fence rw, rw\n" \ + "1:\n" \ + : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \ + : "rJ" (__old), "rJ" (__new) \ + : "memory"); \ + break; \ + default: \ + __ret = 0; \ + ASSERT_UNREACHABLE(); \ + } \ + __ret; \ +}) + +#define cmpxchg(ptr, o, n) \ +({ \ + __typeof__(*(ptr)) _o_ = (o); \ + __typeof__(*(ptr)) _n_ = (n); \ + (__typeof__(*(ptr))) __cmpxchg((ptr), \ + _o_, _n_, sizeof(*(ptr))); \ +}) + +#define cmpxchg_local(ptr, o, n) \ + (__cmpxchg_relaxed((ptr), (o), (n), sizeof(*(ptr)))) + +#define cmpxchg32(ptr, o, n) \ +({ \ + BUILD_BUG_ON(sizeof(*(ptr)) != 4); \ + cmpxchg((ptr), (o), (n)); \ +}) + +#define cmpxchg32_local(ptr, o, n) \ +({ \ + BUILD_BUG_ON(sizeof(*(ptr)) != 4); \ + cmpxchg_relaxed((ptr), (o), (n)) \ +}) + +#define cmpxchg64(ptr, o, n) \ +({ \ + BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ + cmpxchg((ptr), (o), (n)); \ +}) + +#define cmpxchg64_local(ptr, o, n) \ +({ \ + BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ + cmpxchg_relaxed((ptr), (o), (n)); \ +}) + +#endif /* _ASM_RISCV_CMPXCHG_H */ -- 2.42.0