[PATCH 10/17] RISC-V: Atomic and Locking Code
From: Palmer Dabbelt
Date: Tue Jul 11 2017 - 21:32:38 EST
This contains all the code that directly interfaces with the RISC-V
memory model. While this code corforms to the current RISC-V ISA
specifications (user 2.2 and priv 1.10), the memory model is somewhat
underspecified in those documents. There is a working group that hopes
to produce a formal memory model by the end of the year, but my
understanding is that the basic definitions we're relying on here won't
change significantly.
Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxx>
---
arch/riscv/include/asm/atomic.h | 328 ++++++++++++++++++++++++++++++++
arch/riscv/include/asm/barrier.h | 68 +++++++
arch/riscv/include/asm/bitops.h | 216 +++++++++++++++++++++
arch/riscv/include/asm/cacheflush.h | 39 ++++
arch/riscv/include/asm/cmpxchg.h | 134 +++++++++++++
arch/riscv/include/asm/io.h | 180 ++++++++++++++++++
arch/riscv/include/asm/spinlock.h | 165 ++++++++++++++++
arch/riscv/include/asm/spinlock_types.h | 33 ++++
arch/riscv/include/asm/tlb.h | 24 +++
arch/riscv/include/asm/tlbflush.h | 64 +++++++
10 files changed, 1251 insertions(+)
create mode 100644 arch/riscv/include/asm/atomic.h
create mode 100644 arch/riscv/include/asm/barrier.h
create mode 100644 arch/riscv/include/asm/bitops.h
create mode 100644 arch/riscv/include/asm/cacheflush.h
create mode 100644 arch/riscv/include/asm/cmpxchg.h
create mode 100644 arch/riscv/include/asm/io.h
create mode 100644 arch/riscv/include/asm/spinlock.h
create mode 100644 arch/riscv/include/asm/spinlock_types.h
create mode 100644 arch/riscv/include/asm/tlb.h
create mode 100644 arch/riscv/include/asm/tlbflush.h
diff --git a/arch/riscv/include/asm/atomic.h b/arch/riscv/include/asm/atomic.h
new file mode 100644
index 000000000000..ee3ab06e492b
--- /dev/null
+++ b/arch/riscv/include/asm/atomic.h
@@ -0,0 +1,328 @@
+/*
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#ifndef _ASM_RISCV_ATOMIC_H
+#define _ASM_RISCV_ATOMIC_H
+
+#ifdef CONFIG_GENERIC_ATOMIC64
+# include <asm-generic/atomic64.h>
+#else
+# if (__riscv_xlen < 64)
+# error "64-bit atomics require XLEN to be at least 64"
+# endif
+#endif
+
+#include <asm/cmpxchg.h>
+#include <asm/barrier.h>
+
+#define ATOMIC_INIT(i) { (i) }
+static __always_inline int atomic_read(const atomic_t *v)
+{
+ return READ_ONCE(v->counter);
+}
+static __always_inline void atomic_set(atomic_t *v, int i)
+{
+ WRITE_ONCE(v->counter, i);
+}
+
+#ifndef CONFIG_GENERIC_ATOMIC64
+#define ATOMIC64_INIT(i) { (i) }
+static __always_inline int atomic64_read(const atomic64_t *v)
+{
+ return READ_ONCE(v->counter);
+}
+static __always_inline void atomic64_set(atomic64_t *v, int i)
+{
+ WRITE_ONCE(v->counter, i);
+}
+#endif
+
+/*
+ * First, the atomic ops that have no ordering constraints and therefor don't
+ * have the AQ or RL bits set. These don't return anything, so there's only
+ * one version to worry about.
+ */
+#define ATOMIC_OP(op, asm_op, c_op, I, asm_type, c_type, prefix) \
+static __always_inline void atomic##prefix##_##op(c_type i, atomic##prefix##_t *v) \
+{ \
+ __asm__ __volatile__ ( \
+ "amo" #asm_op "." #asm_type " zero, %1, %0" \
+ : "+A" (v->counter) \
+ : "r" (I) \
+ : "memory"); \
+}
+
+#ifdef CONFIG_GENERIC_ATOMIC64
+#define ATOMIC_OPS(op, asm_op, c_op, I) \
+ ATOMIC_OP (op, asm_op, c_op, I, w, int, )
+#else
+#define ATOMIC_OPS(op, asm_op, c_op, I) \
+ ATOMIC_OP (op, asm_op, c_op, I, w, int, ) \
+ ATOMIC_OP (op, asm_op, c_op, I, d, long, 64)
+#endif
+
+ATOMIC_OPS(add, add, +, i)
+ATOMIC_OPS(sub, add, +, -i)
+ATOMIC_OPS(and, and, &, i)
+ATOMIC_OPS( or, or, |, i)
+ATOMIC_OPS(xor, xor, ^, i)
+
+#undef ATOMIC_OP
+#undef ATOMIC_OPS
+
+/*
+ * Atomic ops that have ordered, relaxed, acquire, and relese variants.
+ * There's two flavors of these: the arithmatic ops have both fetch and return
+ * versions, while the logical ops only have fetch versions.
+ */
+#define ATOMIC_FETCH_OP(op, asm_op, c_op, I, asm_or, c_or, asm_type, c_type, prefix) \
+static __always_inline c_type atomic##prefix##_fetch_##op##c_or(c_type i, atomic##prefix##_t *v) \
+{ \
+ register c_type ret; \
+ __asm__ __volatile__ ( \
+ "amo" #asm_op "." #asm_type #asm_or " %1, %2, %0" \
+ : "+A" (v->counter), "=r" (ret) \
+ : "r" (I) \
+ : "memory"); \
+ return ret; \
+}
+
+#define ATOMIC_OP_RETURN(op, asm_op, c_op, I, asm_or, c_or, asm_type, c_type, prefix) \
+static __always_inline c_type atomic##prefix##_##op##_return##c_or(int i, atomic##prefix##_t *v) \
+{ \
+ return atomic##prefix##_fetch_##op##c_or(i, v) c_op I; \
+}
+
+#ifdef CONFIG_GENERIC_ATOMIC64
+#define ATOMIC_OPS(op, asm_op, c_op, I, asm_or, c_or) \
+ ATOMIC_FETCH_OP (op, asm_op, c_op, I, asm_or, c_or, w, int, ) \
+ ATOMIC_OP_RETURN(op, asm_op, c_op, I, asm_or, c_or, w, int, )
+#else
+#define ATOMIC_OPS(op, asm_op, c_op, I, asm_or, c_or) \
+ ATOMIC_FETCH_OP (op, asm_op, c_op, I, asm_or, c_or, w, int, ) \
+ ATOMIC_OP_RETURN(op, asm_op, c_op, I, asm_or, c_or, w, int, ) \
+ ATOMIC_FETCH_OP (op, asm_op, c_op, I, asm_or, c_or, d, long, 64) \
+ ATOMIC_OP_RETURN(op, asm_op, c_op, I, asm_or, c_or, d, long, 64)
+#endif
+
+ATOMIC_OPS(add, add, +, i, , _relaxed)
+ATOMIC_OPS(add, add, +, i, .aq , _acquire)
+ATOMIC_OPS(add, add, +, i, .rl , _release)
+ATOMIC_OPS(add, add, +, i, .aqrl, )
+
+ATOMIC_OPS(sub, add, +, -i, , _relaxed)
+ATOMIC_OPS(sub, add, +, -i, .aq , _acquire)
+ATOMIC_OPS(sub, add, +, -i, .rl , _release)
+ATOMIC_OPS(sub, add, +, -i, .aqrl, )
+
+#undef ATOMIC_OPS
+
+#ifdef CONFIG_GENERIC_ATOMIC64
+#define ATOMIC_OPS(op, asm_op, c_op, I, asm_or, c_or) \
+ ATOMIC_FETCH_OP(op, asm_op, c_op, I, asm_or, c_or, w, int, )
+#else
+#define ATOMIC_OPS(op, asm_op, c_op, I, asm_or, c_or) \
+ ATOMIC_FETCH_OP(op, asm_op, c_op, I, asm_or, c_or, w, int, ) \
+ ATOMIC_FETCH_OP(op, asm_op, c_op, I, asm_or, c_or, d, long, 64)
+#endif
+
+ATOMIC_OPS(and, and, &, i, , _relaxed)
+ATOMIC_OPS(and, and, &, i, .aq , _acquire)
+ATOMIC_OPS(and, and, &, i, .rl , _release)
+ATOMIC_OPS(and, and, &, i, .aqrl, )
+
+ATOMIC_OPS( or, or, |, i, , _relaxed)
+ATOMIC_OPS( or, or, |, i, .aq , _acquire)
+ATOMIC_OPS( or, or, |, i, .rl , _release)
+ATOMIC_OPS( or, or, |, i, .aqrl, )
+
+ATOMIC_OPS(xor, xor, ^, i, , _relaxed)
+ATOMIC_OPS(xor, xor, ^, i, .aq , _acquire)
+ATOMIC_OPS(xor, xor, ^, i, .rl , _release)
+ATOMIC_OPS(xor, xor, ^, i, .aqrl, )
+
+#undef ATOMIC_OPS
+
+#undef ATOMIC_FETCH_OP
+#undef ATOMIC_OP_RETURN
+
+/*
+ * The extra atomic operations that are constructed from one of the core
+ * AMO-based operations above (aside from sub, which is easier to fit above).
+ * These are required to perform a barrier, but they're OK this way because
+ * atomic_*_return is also required to perform a barrier.
+ */
+#define ATOMIC_OP(op, func_op, comp_op, I, c_type, prefix) \
+static __always_inline bool atomic##prefix##_##op(c_type i, atomic##prefix##_t *v) \
+{ \
+ return atomic##prefix##_##func_op##_return(i, v) comp_op I; \
+}
+
+#ifdef CONFIG_GENERIC_ATOMIC64
+#define ATOMIC_OPS(op, func_op, comp_op, I) \
+ ATOMIC_OP (op, func_op, comp_op, I, int, )
+#else
+#define ATOMIC_OPS(op, func_op, comp_op, I) \
+ ATOMIC_OP (op, func_op, comp_op, I, int, ) \
+ ATOMIC_OP (op, func_op, comp_op, I, long, 64)
+#endif
+
+ATOMIC_OPS(add_and_test, add, ==, 0)
+ATOMIC_OPS(sub_and_test, sub, ==, 0)
+ATOMIC_OPS(add_negative, add, <, 0)
+
+#undef ATOMIC_OP
+#undef ATOMIC_OPS
+
+#define ATOMIC_OP(op, func_op, c_op, I, prefix) \
+static __always_inline void atomic##prefix##_##op(atomic##prefix##_t *v) \
+{ \
+ atomic##prefix##_##func_op(I, v); \
+}
+
+#define ATOMIC_FETCH_OP(op, func_op, c_op, I, prefix) \
+static __always_inline int atomic##prefix##_fetch_##op(atomic##prefix##_t *v) \
+{ \
+ return atomic##prefix##_fetch_##func_op(I, v); \
+}
+
+#define ATOMIC_OP_RETURN(op, asm_op, c_op, I, prefix) \
+static __always_inline int atomic##prefix##_##op##_return(atomic##prefix##_t *v) \
+{ \
+ return atomic##prefix##_fetch_##op(v) c_op I; \
+}
+
+#ifdef CONFIG_GENERIC_ATOMIC64
+#define ATOMIC_OPS(op, asm_op, c_op, I) \
+ ATOMIC_OP (op, asm_op, c_op, I, ) \
+ ATOMIC_FETCH_OP (op, asm_op, c_op, I, ) \
+ ATOMIC_OP_RETURN(op, asm_op, c_op, I, )
+#else
+#define ATOMIC_OPS(op, asm_op, c_op, I) \
+ ATOMIC_OP (op, asm_op, c_op, I, ) \
+ ATOMIC_FETCH_OP (op, asm_op, c_op, I, ) \
+ ATOMIC_OP_RETURN(op, asm_op, c_op, I, ) \
+ ATOMIC_OP (op, asm_op, c_op, I, 64) \
+ ATOMIC_FETCH_OP (op, asm_op, c_op, I, 64) \
+ ATOMIC_OP_RETURN(op, asm_op, c_op, I, 64)
+#endif
+
+ATOMIC_OPS(inc, add, +, 1)
+ATOMIC_OPS(dec, add, +, -1)
+
+#undef ATOMIC_OPS
+#undef ATOMIC_OP
+#undef ATOMIC_FETCH_OP
+#undef ATOMIC_OP_RETURN
+
+#define ATOMIC_OP(op, func_op, comp_op, I, prefix) \
+static __always_inline bool atomic##prefix##_##op(atomic##prefix##_t *v) \
+{ \
+ return atomic##prefix##_##func_op##_return(v) comp_op I; \
+}
+
+ATOMIC_OP(inc_and_test, inc, ==, 0, )
+ATOMIC_OP(dec_and_test, dec, ==, 0, )
+#ifndef CONFIG_GENERIC_ATOMIC64
+ATOMIC_OP(inc_and_test, inc, ==, 0, 64)
+ATOMIC_OP(dec_and_test, dec, ==, 0, 64)
+#endif
+
+#undef ATOMIC_OP
+
+/* This is required to provide a barrier on success. */
+static __always_inline int __atomic_add_unless(atomic_t *v, int a, int u)
+{
+ register int prev, rc;
+
+ __asm__ __volatile__ (
+ "0:\n\t"
+ "lr.w.aqrl %0, %2\n\t"
+ "beq %0, %4, 1f\n\t"
+ "add %1, %0, %3\n\t"
+ "sc.w.aqrl %1, %1, %2\n\t"
+ "bnez %1, 0b\n\t"
+ "1:"
+ : "=&r" (prev), "=&r" (rc), "+A" (v->counter)
+ : "r" (a), "r" (u)
+ : "memory");
+ return prev;
+}
+
+#ifndef CONFIG_GENERIC_ATOMIC64
+static __always_inline long atomic64_add_unless(atomic64_t *v, long a, long u)
+{
+ register long prev, rc;
+
+ __asm__ __volatile__ (
+ "0:\n\t"
+ "lr.d.aqrl %0, %2\n\t"
+ "beq %0, %4, 1f\n\t"
+ "add %1, %0, %3\n\t"
+ "sc.d.aqrl %1, %1, %2\n\t"
+ "bnez %1, 0b\n\t"
+ "1:"
+ : "=&r" (prev), "=&r" (rc), "+A" (v->counter)
+ : "r" (a), "r" (u)
+ : "memory");
+ return prev;
+}
+#endif
+
+/*
+ * The extra atomic operations that are constructed from one of the core
+ * LR/SC-based operations above.
+ */
+static __always_inline int atomic_inc_not_zero(atomic_t *v)
+{
+ return __atomic_add_unless(v, 1, 0);
+}
+
+#ifndef CONFIG_GENERIC_ATOMIC64
+static __always_inline int atomic64_inc_not_zero(atomic64_t *v)
+{
+ return atomic64_add_unless(v, 1, 0);
+}
+#endif
+
+/*
+ * atomic_{cmp,}xchg is required to have exactly the same ordering semantics as
+ * {cmp,}xchg and the operations that return, so they need a barrier. We just
+ * use the other implementations directly.
+ */
+#define ATOMIC_OP(c_t, prefix, c_or, size, asm_or) \
+static __always_inline c_t atomic##prefix##_cmpxchg##c_or(atomic##prefix##_t *v, c_t o, c_t n) \
+{ \
+ return __cmpxchg(&(v->counter), o, n, size, asm_or, asm_or); \
+} \
+static __always_inline c_t atomic##prefix##_xchg##c_or(atomic##prefix##_t *v, c_t n) \
+{ \
+ return __xchg(n, &(v->counter), size, asm_or); \
+}
+
+#ifdef CONFIG_GENERIC_ATOMIC64
+#define ATOMIC_OPS(c_or, asm_or) \
+ ATOMIC_OP( int, , c_or, 4, asm_or)
+#else
+#define ATOMIC_OPS(c_or, asm_or) \
+ ATOMIC_OP( int, , c_or, 4, asm_or) \
+ ATOMIC_OP(long, 64, c_or, 8, asm_or)
+#endif
+
+ATOMIC_OPS( , .aqrl)
+ATOMIC_OPS(_acquire, .aq)
+ATOMIC_OPS(_release, .rl)
+ATOMIC_OPS(_relaxed, )
+
+#undef ATOMIC_OPS
+#undef ATOMIC_OP
+
+#endif /* _ASM_RISCV_ATOMIC_H */
diff --git a/arch/riscv/include/asm/barrier.h b/arch/riscv/include/asm/barrier.h
new file mode 100644
index 000000000000..183534b7c39b
--- /dev/null
+++ b/arch/riscv/include/asm/barrier.h
@@ -0,0 +1,68 @@
+/*
+ * Based on arch/arm/include/asm/barrier.h
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Copyright (C) 2013 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _ASM_RISCV_BARRIER_H
+#define _ASM_RISCV_BARRIER_H
+
+#ifndef __ASSEMBLY__
+
+#define nop() __asm__ __volatile__ ("nop")
+
+#define RISCV_FENCE(p, s) \
+ __asm__ __volatile__ ("fence " #p "," #s : : : "memory")
+
+/* These barriers need to enforce ordering on both devices or memory. */
+#define mb() RISCV_FENCE(iorw,iorw)
+#define rmb() RISCV_FENCE(ir,ir)
+#define wmb() RISCV_FENCE(ow,ow)
+
+/* These barriers do not need to enforce ordering on devices, just memory. */
+#define smp_mb() RISCV_FENCE(rw,rw)
+#define smp_rmb() RISCV_FENCE(r,r)
+#define smp_wmb() RISCV_FENCE(w,w)
+
+/*
+ * These fences exist to enforce ordering around the relaxed AMOs. The
+ * documentation defines that
+ * "
+ * atomic_fetch_add();
+ * is equivalent to:
+ * smp_mb__before_atomic();
+ * atomic_fetch_add_relaxed();
+ * smp_mb__after_atomic();
+ * "
+ * So we emit full fences on both sides.
+ */
+#define __smb_mb__before_atomic() smp_mb()
+#define __smb_mb__after_atomic() smp_mb()
+
+/*
+ * These barriers prevent accesses performed outside a spinlock from being moved
+ * inside a spinlock. Since RISC-V sets the aq/rl bits on our spinlock only
+ * enforce release consistency, we need full fences here.
+ */
+#define smb_mb__before_spinlock() smp_mb()
+#define smb_mb__after_spinlock() smp_mb()
+
+#include <asm-generic/barrier.h>
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_RISCV_BARRIER_H */
diff --git a/arch/riscv/include/asm/bitops.h b/arch/riscv/include/asm/bitops.h
new file mode 100644
index 000000000000..b0a0c76e966a
--- /dev/null
+++ b/arch/riscv/include/asm/bitops.h
@@ -0,0 +1,216 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_BITOPS_H
+#define _ASM_RISCV_BITOPS_H
+
+#ifndef _LINUX_BITOPS_H
+#error "Only <linux/bitops.h> can be included directly"
+#endif /* _LINUX_BITOPS_H */
+
+#include <linux/compiler.h>
+#include <linux/irqflags.h>
+#include <asm/barrier.h>
+#include <asm/bitsperlong.h>
+
+#ifndef smp_mb__before_clear_bit
+#define smp_mb__before_clear_bit() smp_mb()
+#define smp_mb__after_clear_bit() smp_mb()
+#endif /* smp_mb__before_clear_bit */
+
+#include <asm-generic/bitops/__ffs.h>
+#include <asm-generic/bitops/ffz.h>
+#include <asm-generic/bitops/fls.h>
+#include <asm-generic/bitops/__fls.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/find.h>
+#include <asm-generic/bitops/sched.h>
+#include <asm-generic/bitops/ffs.h>
+
+#include <asm-generic/bitops/hweight.h>
+
+#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 __test_and_op_bit(op, mod, nr, addr) \
+({ \
+ unsigned long __res, __mask; \
+ __mask = BIT_MASK(nr); \
+ __asm__ __volatile__ ( \
+ __AMO(op) " %0, %2, %1" \
+ : "=r" (__res), "+A" (addr[BIT_WORD(nr)]) \
+ : "r" (mod(__mask))); \
+ ((__res & __mask) != 0); \
+})
+
+#define __op_bit(op, mod, nr, addr) \
+ __asm__ __volatile__ ( \
+ __AMO(op) " zero, %1, %0" \
+ : "+A" (addr[BIT_WORD(nr)]) \
+ : "r" (mod(BIT_MASK(nr))))
+
+/* Bitmask modifiers */
+#define __NOP(x) (x)
+#define __NOT(x) (~(x))
+
+/**
+ * test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It may be reordered on other architectures than x86.
+ * It also implies a memory barrier.
+ */
+static inline int test_and_set_bit(int nr, volatile unsigned long *addr)
+{
+ return __test_and_op_bit(or, __NOP, nr, addr);
+}
+
+/**
+ * test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It can be reordered on other architectures other than x86.
+ * It also implies a memory barrier.
+ */
+static inline int test_and_clear_bit(int nr, volatile unsigned long *addr)
+{
+ return __test_and_op_bit(and, __NOT, nr, addr);
+}
+
+/**
+ * test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static inline int test_and_change_bit(int nr, volatile unsigned long *addr)
+{
+ return __test_and_op_bit(xor, __NOP, nr, addr);
+}
+
+/**
+ * set_bit - Atomically set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This function is atomic and may not be reordered. See __set_bit()
+ * if you do not require the atomic guarantees.
+ *
+ * Note: there are no guarantees that this function will not be reordered
+ * on non x86 architectures, so if you are writing portable code,
+ * make sure not to rely on its reordering guarantees.
+ *
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void set_bit(int nr, volatile unsigned long *addr)
+{
+ __op_bit(or, __NOP, nr, addr);
+}
+
+/**
+ * clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * clear_bit() is atomic and may not be reordered. However, it does
+ * not contain a memory barrier, so if it is used for locking purposes,
+ * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
+ * in order to ensure changes are visible on other processors.
+ */
+static inline void clear_bit(int nr, volatile unsigned long *addr)
+{
+ __op_bit(and, __NOT, nr, addr);
+}
+
+/**
+ * change_bit - Toggle a bit in memory
+ * @nr: Bit to change
+ * @addr: Address to start counting from
+ *
+ * change_bit() is atomic and may not be reordered. It may be
+ * reordered on other architectures than x86.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void change_bit(int nr, volatile unsigned long *addr)
+{
+ __op_bit(xor, __NOP, nr, addr);
+}
+
+/**
+ * test_and_set_bit_lock - Set a bit and return its old value, for lock
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and provides acquire barrier semantics.
+ * It can be used to implement bit locks.
+ */
+static inline int test_and_set_bit_lock(
+ unsigned long nr, volatile unsigned long *addr)
+{
+ return test_and_set_bit(nr, addr);
+}
+
+/**
+ * clear_bit_unlock - Clear a bit in memory, for unlock
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This operation is atomic and provides release barrier semantics.
+ */
+static inline void clear_bit_unlock(
+ unsigned long nr, volatile unsigned long *addr)
+{
+ clear_bit(nr, addr);
+}
+
+/**
+ * __clear_bit_unlock - Clear a bit in memory, for unlock
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This operation is like clear_bit_unlock, however it is not atomic.
+ * It does provide release barrier semantics so it can be used to unlock
+ * a bit lock, however it would only be used if no other CPU can modify
+ * any bits in the memory until the lock is released (a good example is
+ * if the bit lock itself protects access to the other bits in the word).
+ */
+static inline void __clear_bit_unlock(
+ unsigned long nr, volatile unsigned long *addr)
+{
+ clear_bit(nr, addr);
+}
+
+#undef __test_and_op_bit
+#undef __op_bit
+#undef __NOP
+#undef __NOT
+#undef __AMO
+
+#include <asm-generic/bitops/non-atomic.h>
+#include <asm-generic/bitops/le.h>
+#include <asm-generic/bitops/ext2-atomic.h>
+
+#endif /* _ASM_RISCV_BITOPS_H */
diff --git a/arch/riscv/include/asm/cacheflush.h b/arch/riscv/include/asm/cacheflush.h
new file mode 100644
index 000000000000..0595585013b0
--- /dev/null
+++ b/arch/riscv/include/asm/cacheflush.h
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2015 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_CACHEFLUSH_H
+#define _ASM_RISCV_CACHEFLUSH_H
+
+#include <asm-generic/cacheflush.h>
+
+#undef flush_icache_range
+#undef flush_icache_user_range
+
+static inline void local_flush_icache_all(void)
+{
+ asm volatile ("fence.i" ::: "memory");
+}
+
+#ifndef CONFIG_SMP
+
+#define flush_icache_range(start, end) local_flush_icache_all()
+#define flush_icache_user_range(vma, pg, addr, len) local_flush_icache_all()
+
+#else /* CONFIG_SMP */
+
+#define flush_icache_range(start, end) sbi_remote_fence_i(0)
+#define flush_icache_user_range(vma, pg, addr, len) sbi_remote_fence_i(0)
+
+#endif /* CONFIG_SMP */
+
+#endif /* _ASM_RISCV_CACHEFLUSH_H */
diff --git a/arch/riscv/include/asm/cmpxchg.h b/arch/riscv/include/asm/cmpxchg.h
new file mode 100644
index 000000000000..db249dbc7b97
--- /dev/null
+++ b/arch/riscv/include/asm/cmpxchg.h
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2014 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_CMPXCHG_H
+#define _ASM_RISCV_CMPXCHG_H
+
+#include <linux/bug.h>
+
+#include <asm/barrier.h>
+
+#define __xchg(new, ptr, size, asm_or) \
+({ \
+ __typeof__(ptr) __ptr = (ptr); \
+ __typeof__(new) __new = (new); \
+ __typeof__(*(ptr)) __ret; \
+ switch (size) { \
+ case 4: \
+ __asm__ __volatile__ ( \
+ "amoswap.w" #asm_or " %0, %2, %1" \
+ : "=r" (__ret), "+A" (*__ptr) \
+ : "r" (__new) \
+ : "memory"); \
+ break; \
+ case 8: \
+ __asm__ __volatile__ ( \
+ "amoswap.d" #asm_or " %0, %2, %1" \
+ : "=r" (__ret), "+A" (*__ptr) \
+ : "r" (__new) \
+ : "memory"); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ } \
+ __ret; \
+})
+
+#define xchg(ptr, x) (__xchg((x), (ptr), sizeof(*(ptr)), .aqrl))
+
+#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(ptr, old, new, size, lrb, scb) \
+({ \
+ __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" #scb " %0, %2\n" \
+ "bne %0, %z3, 1f\n" \
+ "sc.w" #lrb " %1, %z4, %2\n" \
+ "bnez %1, 0b\n" \
+ "1:" \
+ : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \
+ : "rJ" (__old), "rJ" (__new) \
+ : "memory"); \
+ break; \
+ case 8: \
+ __asm__ __volatile__ ( \
+ "0:" \
+ "lr.d" #scb " %0, %2\n" \
+ "bne %0, %z3, 1f\n" \
+ "sc.d" #lrb " %1, %z4, %2\n" \
+ "bnez %1, 0b\n" \
+ "1:" \
+ : "=&r" (__ret), "=&r" (__rc), "+A" (*__ptr) \
+ : "rJ" (__old), "rJ" (__new) \
+ : "memory"); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ } \
+ __ret; \
+})
+
+#define cmpxchg(ptr, o, n) \
+ (__cmpxchg((ptr), (o), (n), sizeof(*(ptr)), .aqrl, .aqrl))
+
+#define cmpxchg_local(ptr, o, n) \
+ (__cmpxchg((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_local((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_local((ptr), (o), (n)); \
+})
+
+#endif /* _ASM_RISCV_CMPXCHG_H */
diff --git a/arch/riscv/include/asm/io.h b/arch/riscv/include/asm/io.h
new file mode 100644
index 000000000000..f7d63320ff8e
--- /dev/null
+++ b/arch/riscv/include/asm/io.h
@@ -0,0 +1,180 @@
+/*
+ * {read,write}{b,w,l,q} based on arch/arm64/include/asm/io.h
+ * which was based on arch/arm/include/io.h
+ *
+ * Copyright (C) 1996-2000 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ * Copyright (C) 2014 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_IO_H
+#define _ASM_RISCV_IO_H
+
+#ifdef CONFIG_MMU
+
+extern void __iomem *ioremap(phys_addr_t offset, unsigned long size);
+
+/*
+ * The RISC-V ISA doesn't yet specify how to query of modify PMAs, so we can't
+ * change the properties of memory regions. This should be fixed by the
+ * upcoming platform spec.
+ */
+#define ioremap_nocache(addr, size) ioremap((addr), (size))
+#define ioremap_wc(addr, size) ioremap((addr), (size))
+#define ioremap_wt(addr, size) ioremap((addr), (size))
+
+extern void iounmap(void __iomem *addr);
+
+#endif /* CONFIG_MMU */
+
+/* Generic IO read/write. These perform native-endian accesses. */
+#define __raw_writeb __raw_writeb
+static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
+{
+ asm volatile("sb %0, 0(%1)" : : "r" (val), "r" (addr));
+}
+
+#define __raw_writew __raw_writew
+static inline void __raw_writew(u16 val, volatile void __iomem *addr)
+{
+ asm volatile("sh %0, 0(%1)" : : "r" (val), "r" (addr));
+}
+
+#define __raw_writel __raw_writel
+static inline void __raw_writel(u32 val, volatile void __iomem *addr)
+{
+ asm volatile("sw %0, 0(%1)" : : "r" (val), "r" (addr));
+}
+
+#ifdef __riscv64
+#define __raw_writeq __raw_writeq
+static inline void __raw_writeq(u64 val, volatile void __iomem *addr)
+{
+ asm volatile("sd %0, 0(%1)" : : "r" (val), "r" (addr));
+}
+#endif
+
+#define __raw_readb __raw_readb
+static inline u8 __raw_readb(const volatile void __iomem *addr)
+{
+ u8 val;
+
+ asm volatile("lb %0, 0(%1)" : "=r" (val) : "r" (addr));
+ return val;
+}
+
+#define __raw_readw __raw_readw
+static inline u16 __raw_readw(const volatile void __iomem *addr)
+{
+ u16 val;
+
+ asm volatile("lh %0, 0(%1)" : "=r" (val) : "r" (addr));
+ return val;
+}
+
+#define __raw_readl __raw_readl
+static inline u32 __raw_readl(const volatile void __iomem *addr)
+{
+ u32 val;
+
+ asm volatile("lw %0, 0(%1)" : "=r" (val) : "r" (addr));
+ return val;
+}
+
+#ifdef __riscv64
+#define __raw_readq __raw_readq
+static inline u64 __raw_readq(const volatile void __iomem *addr)
+{
+ u64 val;
+
+ asm volatile("ld %0, 0(%1)" : "=r" (val) : "r" (addr));
+ return val;
+}
+#endif
+
+/*
+ * FIXME: I'm flip-flopping on whether or not we should keep this or enforce
+ * the ordering with I/O on spinlocks. The worry is that drivers won't get
+ * this correct, but I also don't want to introduce a fence into the lock code
+ * that otherwise only uses AMOs and LR/SC. For now I'm leaving this here:
+ * "w,o" is sufficient to ensure that all writes to the device has completed
+ * before the write to the spinlock is allowed to commit. I surmised this from
+ * reading "ACQUIRES VS I/O ACCESSES" in memory-barriers.txt.
+ */
+#define mmiowb() __asm__ __volatile__ ("fence o,w" : : : "memory");
+
+/*
+ * Unordered I/O memory access primitives. These are even more relaxed than
+ * the relaxed versions, as they don't even order accesses between successive
+ * operations to the I/O regions.
+ */
+#define readb_cpu(c) ({ u8 __r = __raw_readb(c); __r; })
+#define readw_cpu(c) ({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; })
+#define readl_cpu(c) ({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; })
+#define readq_cpu(c) ({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; })
+
+#define writeb_cpu(v,c) ((void)__raw_writeb((v),(c)))
+#define writew_cpu(v,c) ((void)__raw_writew((__force u16)cpu_to_le16(v),(c)))
+#define writel_cpu(v,c) ((void)__raw_writel((__force u32)cpu_to_le32(v),(c)))
+#define writeq_cpu(v,c) ((void)__raw_writeq((__force u64)cpu_to_le64(v),(c)))
+
+/*
+ * Relaxed I/O memory access primitives. These follow the Device memory
+ * ordering rules but do not guarantee any ordering relative to Normal memory
+ * accesses. The memory barriers here are necessary as RISC-V doesn't define
+ * any ordering constraints on accesses to the device I/O space. These are
+ * defined to order the indicated access (either a read or write) with all
+ * other I/O memory accesses.
+ */
+/*
+ * FIXME: The platform spec will define the default Linux-capable platform to
+ * have some extra IO ordering constraints that will make these fences
+ * unnecessary.
+ */
+#define __iorrmb() __asm__ __volatile__ ("fence i,io" : : : "memory");
+#define __iorwmb() __asm__ __volatile__ ("fence io,o" : : : "memory");
+
+#define readb_relaxed(c) ({ u8 __v = readb_cpu(c); __iorrmb(); __v; })
+#define readw_relaxed(c) ({ u16 __v = readw_cpu(c); __iorrmb(); __v; })
+#define readl_relaxed(c) ({ u32 __v = readl_cpu(c); __iorrmb(); __v; })
+#define readq_relaxed(c) ({ u64 __v = readq_cpu(c); __iorrmb(); __v; })
+
+#define writeb_relaxed(v,c) ({ __iorwmb(); writeb_cpu((v),(c)); })
+#define writew_relaxed(v,c) ({ __iorwmb(); writew_cpu((v),(c)); })
+#define writel_relaxed(v,c) ({ __iorwmb(); writel_cpu((v),(c)); })
+#define writeq_relaxed(v,c) ({ __iorwmb(); writeq_cpu((v),(c)); })
+
+/*
+ * I/O memory access primitives. Reads are ordered relative to any
+ * following Normal memory access. Writes are ordered relative to any prior
+ * Normal memory access. The memory barriers here are necessary as RISC-V
+ * doesn't define any ordering between the memory space and the I/O space.
+ * They may be stronger than necessary ("i,r" and "w,o" might be sufficient),
+ * but I feel kind of queasy making these weaker in any manner than the relaxed
+ * versions above.
+ */
+#define __iormb() __asm__ __volatile__ ("fence i,ior" : : : "memory");
+#define __iowmb() __asm__ __volatile__ ("fence iow,o" : : : "memory");
+
+#define readb(c) ({ u8 __v = readb_cpu(c); __iormb(); __v; })
+#define readw(c) ({ u16 __v = readw_cpu(c); __iormb(); __v; })
+#define readl(c) ({ u32 __v = readl_cpu(c); __iormb(); __v; })
+#define readq(c) ({ u64 __v = readq_cpu(c); __iormb(); __v; })
+
+#define writeb(v,c) ({ __iowmb(); writeb_cpu((v),(c)); })
+#define writew(v,c) ({ __iowmb(); writew_cpu((v),(c)); })
+#define writel(v,c) ({ __iowmb(); writel_cpu((v),(c)); })
+#define writeq(v,c) ({ __iowmb(); writeq_cpu((v),(c)); })
+
+#include <asm-generic/io.h>
+
+#endif /* _ASM_RISCV_IO_H */
diff --git a/arch/riscv/include/asm/spinlock.h b/arch/riscv/include/asm/spinlock.h
new file mode 100644
index 000000000000..b3b394ffaf7e
--- /dev/null
+++ b/arch/riscv/include/asm/spinlock.h
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2015 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_SPINLOCK_H
+#define _ASM_RISCV_SPINLOCK_H
+
+#include <linux/kernel.h>
+#include <asm/current.h>
+
+/*
+ * Simple spin lock operations. These provide no fairness guarantees.
+ */
+
+/* FIXME: Replace this with a ticket lock, like MIPS. */
+
+#define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock)
+#define arch_spin_is_locked(x) ((x)->lock != 0)
+
+static inline void arch_spin_unlock(arch_spinlock_t *lock)
+{
+ __asm__ __volatile__ (
+ "amoswap.w.rl x0, x0, %0"
+ : "=A" (lock->lock)
+ :: "memory");
+}
+
+static inline int arch_spin_trylock(arch_spinlock_t *lock)
+{
+ int tmp = 1, busy;
+
+ __asm__ __volatile__ (
+ "amoswap.w.aq %0, %2, %1"
+ : "=r" (busy), "+A" (lock->lock)
+ : "r" (tmp)
+ : "memory");
+
+ return !busy;
+}
+
+static inline void arch_spin_lock(arch_spinlock_t *lock)
+{
+ while (1) {
+ if (arch_spin_is_locked(lock))
+ continue;
+
+ if (arch_spin_trylock(lock))
+ break;
+ }
+}
+
+static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
+{
+ smp_rmb();
+ do {
+ cpu_relax();
+ } while (arch_spin_is_locked(lock));
+ smp_acquire__after_ctrl_dep();
+}
+
+/***********************************************************/
+
+static inline int arch_read_can_lock(arch_rwlock_t *lock)
+{
+ return lock->lock >= 0;
+}
+
+static inline int arch_write_can_lock(arch_rwlock_t *lock)
+{
+ return lock->lock == 0;
+}
+
+static inline void arch_read_lock(arch_rwlock_t *lock)
+{
+ int tmp;
+
+ __asm__ __volatile__(
+ "1: lr.w %1, %0\n"
+ " bltz %1, 1b\n"
+ " addi %1, %1, 1\n"
+ " sc.w.aq %1, %1, %0\n"
+ " bnez %1, 1b\n"
+ : "+A" (lock->lock), "=&r" (tmp)
+ :: "memory");
+}
+
+static inline void arch_write_lock(arch_rwlock_t *lock)
+{
+ int tmp;
+
+ __asm__ __volatile__(
+ "1: lr.w %1, %0\n"
+ " bnez %1, 1b\n"
+ " li %1, -1\n"
+ " sc.w.aq %1, %1, %0\n"
+ " bnez %1, 1b\n"
+ : "+A" (lock->lock), "=&r" (tmp)
+ :: "memory");
+}
+
+static inline int arch_read_trylock(arch_rwlock_t *lock)
+{
+ int busy;
+
+ __asm__ __volatile__(
+ "1: lr.w %1, %0\n"
+ " bltz %1, 1f\n"
+ " addi %1, %1, 1\n"
+ " sc.w.aq %1, %1, %0\n"
+ " bnez %1, 1b\n"
+ "1:\n"
+ : "+A" (lock->lock), "=&r" (busy)
+ :: "memory");
+
+ return !busy;
+}
+
+static inline int arch_write_trylock(arch_rwlock_t *lock)
+{
+ int busy;
+
+ __asm__ __volatile__(
+ "1: lr.w %1, %0\n"
+ " bnez %1, 1f\n"
+ " li %1, -1\n"
+ " sc.w.aq %1, %1, %0\n"
+ " bnez %1, 1b\n"
+ "1:\n"
+ : "+A" (lock->lock), "=&r" (busy)
+ :: "memory");
+
+ return !busy;
+}
+
+static inline void arch_read_unlock(arch_rwlock_t *lock)
+{
+ __asm__ __volatile__(
+ "amoadd.w.rl x0, %1, %0"
+ : "+A" (lock->lock)
+ : "r" (-1)
+ : "memory");
+}
+
+static inline void arch_write_unlock(arch_rwlock_t *lock)
+{
+ __asm__ __volatile__ (
+ "amoswap.w.rl x0, x0, %0"
+ : "=A" (lock->lock)
+ :: "memory");
+}
+
+#define arch_read_lock_flags(lock, flags) arch_read_lock(lock)
+#define arch_write_lock_flags(lock, flags) arch_write_lock(lock)
+
+#endif /* _ASM_RISCV_SPINLOCK_H */
diff --git a/arch/riscv/include/asm/spinlock_types.h b/arch/riscv/include/asm/spinlock_types.h
new file mode 100644
index 000000000000..83ac4ac9e2ac
--- /dev/null
+++ b/arch/riscv/include/asm/spinlock_types.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2015 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_SPINLOCK_TYPES_H
+#define _ASM_RISCV_SPINLOCK_TYPES_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+# error "please don't include this file directly"
+#endif
+
+typedef struct {
+ volatile unsigned int lock;
+} arch_spinlock_t;
+
+#define __ARCH_SPIN_LOCK_UNLOCKED { 0 }
+
+typedef struct {
+ volatile unsigned int lock;
+} arch_rwlock_t;
+
+#define __ARCH_RW_LOCK_UNLOCKED { 0 }
+
+#endif
diff --git a/arch/riscv/include/asm/tlb.h b/arch/riscv/include/asm/tlb.h
new file mode 100644
index 000000000000..c229509288ea
--- /dev/null
+++ b/arch/riscv/include/asm/tlb.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_TLB_H
+#define _ASM_RISCV_TLB_H
+
+#include <asm-generic/tlb.h>
+
+static inline void tlb_flush(struct mmu_gather *tlb)
+{
+ flush_tlb_mm(tlb->mm);
+}
+
+#endif /* _ASM_RISCV_TLB_H */
diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h
new file mode 100644
index 000000000000..5ee4ae370b5e
--- /dev/null
+++ b/arch/riscv/include/asm/tlbflush.h
@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2009 Chen Liqin <liqin.chen@xxxxxxxxxxxxx>
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_TLBFLUSH_H
+#define _ASM_RISCV_TLBFLUSH_H
+
+#ifdef CONFIG_MMU
+
+/* Flush entire local TLB */
+static inline void local_flush_tlb_all(void)
+{
+ __asm__ __volatile__ ("sfence.vma" : : : "memory");
+}
+
+/* Flush one page from local TLB */
+static inline void local_flush_tlb_page(unsigned long addr)
+{
+ __asm__ __volatile__ ("sfence.vma %0" : : "r" (addr) : "memory");
+}
+
+#ifndef CONFIG_SMP
+
+#define flush_tlb_all() local_flush_tlb_all()
+#define flush_tlb_page(vma, addr) local_flush_tlb_page(addr)
+#define flush_tlb_range(vma, start, end) local_flush_tlb_all()
+
+#else /* CONFIG_SMP */
+
+#include <asm/sbi.h>
+
+#define flush_tlb_all() sbi_remote_sfence_vma(0, 0, -1)
+#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
+#define flush_tlb_range(vma, start, end) \
+ sbi_remote_sfence_vma(0, start, (end) - (start))
+
+#endif /* CONFIG_SMP */
+
+/* Flush the TLB entries of the specified mm context */
+static inline void flush_tlb_mm(struct mm_struct *mm)
+{
+ flush_tlb_all();
+}
+
+/* Flush a range of kernel pages */
+static inline void flush_tlb_kernel_range(unsigned long start,
+ unsigned long end)
+{
+ flush_tlb_all();
+}
+
+#endif /* CONFIG_MMU */
+
+#endif /* _ASM_RISCV_TLBFLUSH_H */
--
2.13.0