lib: Move sbi core library to lib/sbi

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Anup Patel <anup.patel@wdc.com>

1 files changed, 222 insertions, 0 deletions

diff --git a/lib/sbi/riscv_atomic.c b/lib/sbi/riscv_atomic.c
new file mode 100644
index 0000000..34bf522
--- /dev/null
+++ b/lib/sbi/riscv_atomic.c
@@ -0,0 +1,222 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ */
+
+#include <sbi/sbi_types.h>
+#include <sbi/riscv_asm.h>
+#include <sbi/riscv_atomic.h>
+#include <sbi/riscv_barrier.h>
+#include <sbi/sbi_bits.h>
+
+long atomic_read(atomic_t *atom)
+{
+	long ret = atom->counter;
+	rmb();
+	return ret;
+}
+
+void atomic_write(atomic_t *atom, long value)
+{
+	atom->counter = value;
+	wmb();
+}
+
+long atomic_add_return(atomic_t *atom, long value)
+{
+	long ret;
+
+	__asm__ __volatile__("	amoadd.w.aqrl  %1, %2, %0"
+			     : "+A"(atom->counter), "=r"(ret)
+			     : "r"(value)
+			     : "memory");
+
+	return ret + value;
+}
+
+long atomic_sub_return(atomic_t *atom, long value)
+{
+	long ret;
+
+	__asm__ __volatile__("	amoadd.w.aqrl  %1, %2, %0"
+			     : "+A"(atom->counter), "=r"(ret)
+			     : "r"(-value)
+			     : "memory");
+
+	return ret - value;
+}
+
+#define __xchg(ptr, new, size)                                            \
+	({                                                                \
+		__typeof__(ptr) __ptr	 = (ptr);                         \
+		__typeof__(*(ptr)) __new = (new);                         \
+		__typeof__(*(ptr)) __ret;                                 \
+		register unsigned int __rc;                               \
+		switch (size) {                                           \
+		case 4:                                                   \
+			__asm__ __volatile__("0:	lr.w %0, %2\n"           \
+					     "	sc.w.rl %1, %z3, %2\n"     \
+					     "	bnez %1, 0b\n"             \
+					     "	fence rw, rw\n"            \
+					     : "=&r"(__ret), "=&r"(__rc), \
+					       "+A"(*__ptr)               \
+					     : "rJ"(__new)                \
+					     : "memory");                 \
+			break;                                            \
+		case 8:                                                   \
+			__asm__ __volatile__("0:	lr.d %0, %2\n"           \
+					     "	sc.d.rl %1, %z3, %2\n"     \
+					     "	bnez %1, 0b\n"             \
+					     "	fence rw, rw\n"            \
+					     : "=&r"(__ret), "=&r"(__rc), \
+					       "+A"(*__ptr)               \
+					     : "rJ"(__new)                \
+					     : "memory");                 \
+			break;                                            \
+		default:                                                  \
+			break;                                            \
+		}                                                         \
+		__ret;                                                    \
+	})
+
+#define xchg(ptr, n)                                                     \
+	({                                                               \
+		__typeof__(*(ptr)) _n_ = (n);                            \
+		(__typeof__(*(ptr))) __xchg((ptr), _n_, sizeof(*(ptr))); \
+	})
+
+#define __cmpxchg(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.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:                                                  \
+			break;                                            \
+		}                                                         \
+		__ret;                                                    \
+	})
+
+#define cmpxchg(ptr, o, n)                                          \
+	({                                                          \
+		__typeof__(*(ptr)) _o_ = (o);                       \
+		__typeof__(*(ptr)) _n_ = (n);                       \
+		(__typeof__(*(ptr)))                                \
+			__cmpxchg((ptr), _o_, _n_, sizeof(*(ptr))); \
+	})
+
+long arch_atomic_cmpxchg(atomic_t *atom, long oldval, long newval)
+{
+#ifdef __riscv_atomic
+	return __sync_val_compare_and_swap(&atom->counter, oldval, newval);
+#else
+	return cmpxchg(&atom->counter, oldval, newval);
+#endif
+}
+
+long arch_atomic_xchg(atomic_t *atom, long newval)
+{
+	/* Atomically set new value and return old value. */
+#ifdef __riscv_atomic
+	/*
+	 * The name of GCC built-in macro __sync_lock_test_and_set()
+	 * is misleading. A more appropriate name for GCC built-in
+	 * macro would be __sync_val_exchange().
+	 */
+	return __sync_lock_test_and_set(&atom->counter, newval);
+#else
+	return xchg(&atom->counter, newval);
+#endif
+}
+
+unsigned int atomic_raw_xchg_uint(volatile unsigned int *ptr,
+				  unsigned int newval)
+{
+	/* Atomically set new value and return old value. */
+#ifdef __riscv_atomic
+	/*
+	 * The name of GCC built-in macro __sync_lock_test_and_set()
+	 * is misleading. A more appropriate name for GCC built-in
+	 * macro would be __sync_val_exchange().
+	 */
+	return __sync_lock_test_and_set(ptr, newval);
+#else
+	return xchg(ptr, newval);
+#endif
+}
+
+#if (BITS_PER_LONG == 64)
+#define __AMO(op) "amo" #op ".d"
+#elif (BITS_PER_LONG == 32)
+#define __AMO(op) "amo" #op ".w"
+#else
+#error "Unexpected BITS_PER_LONG"
+#endif
+
+#define __atomic_op_bit_ord(op, mod, nr, addr, ord)                          \
+	({                                                                   \
+		unsigned long __res, __mask;                                 \
+		__mask = BIT_MASK(nr);                                       \
+		__asm__ __volatile__(__AMO(op) #ord " %0, %2, %1"            \
+				     : "=r"(__res), "+A"(addr[BIT_WORD(nr)]) \
+				     : "r"(mod(__mask))                      \
+				     : "memory");                            \
+		__res;                                                       \
+	})
+
+#define __atomic_op_bit(op, mod, nr, addr) \
+	__atomic_op_bit_ord(op, mod, nr, addr, .aqrl)
+
+/* Bitmask modifiers */
+#define __NOP(x) (x)
+#define __NOT(x) (~(x))
+
+inline int atomic_raw_set_bit(int nr, volatile unsigned long *addr)
+{
+	return __atomic_op_bit(or, __NOP, nr, addr);
+}
+
+inline int atomic_raw_clear_bit(int nr, volatile unsigned long *addr)
+{
+	return __atomic_op_bit(and, __NOT, nr, addr);
+}
+
+inline int atomic_set_bit(int nr, atomic_t *atom)
+{
+	return atomic_raw_set_bit(nr, (unsigned long *)&atom->counter);
+}
+
+inline int atomic_clear_bit(int nr, atomic_t *atom)
+{
+	return atomic_raw_clear_bit(nr, (unsigned long *)&atom->counter);
+}