lkml.org 
[lkml]   [2018]   [Jul]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH V2 11/19] csky: Atomic operations
Date
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
---
arch/csky/include/asm/cmpxchg.h | 68 +++++++++++++
arch/csky/include/asm/spinlock.h | 174 +++++++++++++++++++++++++++++++++
arch/csky/include/asm/spinlock_types.h | 20 ++++
arch/csky/kernel/atomic.S | 87 +++++++++++++++++
4 files changed, 349 insertions(+)
create mode 100644 arch/csky/include/asm/cmpxchg.h
create mode 100644 arch/csky/include/asm/spinlock.h
create mode 100644 arch/csky/include/asm/spinlock_types.h
create mode 100644 arch/csky/kernel/atomic.S

diff --git a/arch/csky/include/asm/cmpxchg.h b/arch/csky/include/asm/cmpxchg.h
new file mode 100644
index 0000000..1c30a28
--- /dev/null
+++ b/arch/csky/include/asm/cmpxchg.h
@@ -0,0 +1,68 @@
+#ifndef __ASM_CSKY_CMPXCHG_H
+#define __ASM_CSKY_CMPXCHG_H
+
+#ifdef CONFIG_CPU_HAS_LDSTEX
+#include <linux/bug.h>
+#include <asm/barrier.h>
+
+#define __xchg(new, ptr, size) \
+({ \
+ __typeof__(ptr) __ptr = (ptr); \
+ __typeof__(new) __new = (new); \
+ __typeof__(*(ptr)) __ret; \
+ unsigned long tmp; \
+ switch (size) { \
+ case 4: \
+ asm volatile ( \
+ "1: ldex.w %0, (%3) \n" \
+ " mov %1, %2 \n" \
+ " stex.w %1, (%3) \n" \
+ " bez %1, 1b \n" \
+ : "=&r" (__ret), "=&r" (tmp) \
+ : "r" (__new), "r"(__ptr) \
+ : "memory"); \
+ smp_mb(); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ } \
+ __ret; \
+})
+
+#define xchg(ptr, x) (__xchg((x), (ptr), sizeof(*(ptr))))
+
+#define __cmpxchg(ptr, old, new, size) \
+({ \
+ __typeof__(ptr) __ptr = (ptr); \
+ __typeof__(new) __new = (new); \
+ __typeof__(new) __tmp; \
+ __typeof__(old) __old = (old); \
+ __typeof__(*(ptr)) __ret; \
+ switch (size) { \
+ case 4: \
+ asm volatile ( \
+ "1: ldex.w %0, (%3) \n" \
+ " cmpne %0, %4 \n" \
+ " bt 2f \n" \
+ " mov %1, %2 \n" \
+ " stex.w %1, (%3) \n" \
+ " bez %1, 1b \n" \
+ "2: \n" \
+ : "=&r" (__ret), "=&r" (__tmp) \
+ : "r" (__new), "r"(__ptr), "r"(__old) \
+ : "memory"); \
+ smp_mb(); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ } \
+ __ret; \
+})
+
+#define cmpxchg(ptr, o, n) \
+ (__cmpxchg((ptr), (o), (n), sizeof(*(ptr))))
+#else
+#include <asm-generic/cmpxchg.h>
+#endif
+
+#endif /* __ASM_CSKY_CMPXCHG_H */
diff --git a/arch/csky/include/asm/spinlock.h b/arch/csky/include/asm/spinlock.h
new file mode 100644
index 0000000..ca10d0e
--- /dev/null
+++ b/arch/csky/include/asm/spinlock.h
@@ -0,0 +1,174 @@
+#ifndef __ASM_CSKY_SPINLOCK_H
+#define __ASM_CSKY_SPINLOCK_H
+
+#include <linux/spinlock_types.h>
+#include <asm/barrier.h>
+
+#define arch_spin_is_locked(x) (READ_ONCE((x)->lock) != 0)
+
+/****** spin lock/unlock/trylock ******/
+static inline void arch_spin_lock(arch_spinlock_t *lock)
+{
+ unsigned int *p = &lock->lock;
+ unsigned int tmp;
+
+ asm volatile (
+ "1: ldex.w %0, (%1) \n"
+ " bnez %0, 1b \n"
+ " movi %0, 1 \n"
+ " stex.w %0, (%1) \n"
+ " bez %0, 1b \n"
+ : "=&r" (tmp)
+ : "r"(p)
+ : "memory");
+ smp_mb();
+}
+
+static inline void arch_spin_unlock(arch_spinlock_t *lock)
+{
+ unsigned int *p = &lock->lock;
+ unsigned int tmp;
+
+ smp_mb();
+ asm volatile (
+ "1: ldex.w %0, (%1) \n"
+ " movi %0, 0 \n"
+ " stex.w %0, (%1) \n"
+ " bez %0, 1b \n"
+ : "=&r" (tmp)
+ : "r"(p)
+ : "memory");
+}
+
+static inline int arch_spin_trylock(arch_spinlock_t *lock)
+{
+ unsigned int *p = &lock->lock;
+ unsigned int tmp;
+
+ asm volatile (
+ "1: ldex.w %0, (%1) \n"
+ " bnez %0, 2f \n"
+ " movi %0, 1 \n"
+ " stex.w %0, (%1) \n"
+ " bez %0, 1b \n"
+ " movi %0, 0 \n"
+ "2: \n"
+ : "=&r" (tmp)
+ : "r"(p)
+ : "memory");
+ smp_mb();
+
+ return !tmp;
+}
+
+/****** read lock/unlock/trylock ******/
+static inline void arch_read_lock(arch_rwlock_t *lock)
+{
+ unsigned int *p = &lock->lock;
+ unsigned int tmp;
+
+ asm volatile (
+ "1: ldex.w %0, (%1) \n"
+ " blz %0, 1b \n"
+ " addi %0, 1 \n"
+ " stex.w %0, (%1) \n"
+ " bez %0, 1b \n"
+ : "=&r" (tmp)
+ : "r"(p)
+ : "memory");
+ smp_mb();
+}
+
+static inline void arch_read_unlock(arch_rwlock_t *lock)
+{
+ unsigned int *p = &lock->lock;
+ unsigned int tmp;
+
+ smp_mb();
+ asm volatile (
+ "1: ldex.w %0, (%1) \n"
+ " subi %0, 1 \n"
+ " stex.w %0, (%1) \n"
+ " bez %0, 1b \n"
+ : "=&r" (tmp)
+ : "r"(p)
+ : "memory");
+}
+
+static inline int arch_read_trylock(arch_rwlock_t *lock)
+{
+ unsigned int *p = &lock->lock;
+ unsigned int tmp;
+
+ asm volatile (
+ "1: ldex.w %0, (%1) \n"
+ " blz %0, 2f \n"
+ " addi %0, 1 \n"
+ " stex.w %0, (%1) \n"
+ " bez %0, 1b \n"
+ " movi %0, 0 \n"
+ "2: \n"
+ : "=&r" (tmp)
+ : "r"(p)
+ : "memory");
+ smp_mb();
+
+ return !tmp;
+}
+
+/****** write lock/unlock/trylock ******/
+static inline void arch_write_lock(arch_rwlock_t *lock)
+{
+ unsigned int *p = &lock->lock;
+ unsigned int tmp;
+
+ asm volatile (
+ "1: ldex.w %0, (%1) \n"
+ " bnez %0, 1b \n"
+ " subi %0, 1 \n"
+ " stex.w %0, (%1) \n"
+ " bez %0, 1b \n"
+ : "=&r" (tmp)
+ : "r"(p)
+ : "memory");
+ smp_mb();
+}
+
+static inline void arch_write_unlock(arch_rwlock_t *lock)
+{
+ unsigned int *p = &lock->lock;
+ unsigned int tmp;
+
+ smp_mb();
+ asm volatile (
+ "1: ldex.w %0, (%1) \n"
+ " movi %0, 0 \n"
+ " stex.w %0, (%1) \n"
+ " bez %0, 1b \n"
+ : "=&r" (tmp)
+ : "r"(p)
+ : "memory");
+}
+
+static inline int arch_write_trylock(arch_rwlock_t *lock)
+{
+ unsigned int *p = &lock->lock;
+ unsigned int tmp;
+
+ asm volatile (
+ "1: ldex.w %0, (%1) \n"
+ " bnez %0, 2f \n"
+ " subi %0, 1 \n"
+ " stex.w %0, (%1) \n"
+ " bez %0, 1b \n"
+ " movi %0, 0 \n"
+ "2: \n"
+ : "=&r" (tmp)
+ : "r"(p)
+ : "memory");
+ smp_mb();
+
+ return !tmp;
+}
+
+#endif /* __ASM_CSKY_SPINLOCK_H */
diff --git a/arch/csky/include/asm/spinlock_types.h b/arch/csky/include/asm/spinlock_types.h
new file mode 100644
index 0000000..ea890ef
--- /dev/null
+++ b/arch/csky/include/asm/spinlock_types.h
@@ -0,0 +1,20 @@
+#ifndef __ASM_CSKY_SPINLOCK_TYPES_H
+#define __ASM_CSKY_SPINLOCK_TYPES_H
+
+#ifndef __LINUX_SPINLOCK_TYPES_H
+# error "please don't include this file directly"
+#endif
+
+typedef struct {
+ unsigned int lock;
+} arch_spinlock_t;
+
+#define __ARCH_SPIN_LOCK_UNLOCKED { 0 }
+
+typedef struct {
+ unsigned int lock;
+} arch_rwlock_t;
+
+#define __ARCH_RW_LOCK_UNLOCKED { 0 }
+
+#endif
diff --git a/arch/csky/kernel/atomic.S b/arch/csky/kernel/atomic.S
new file mode 100644
index 0000000..95ae696
--- /dev/null
+++ b/arch/csky/kernel/atomic.S
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+#include <linux/linkage.h>
+#include <abi/entry.h>
+
+.text
+
+/*
+ * int csky_cmpxchg(int oldval, int newval, int *ptr)
+ *
+ * If *ptr != oldval && return 1,
+ * else *ptr = newval return 0.
+ */
+#ifdef CONFIG_CPU_HAS_LDSTEX
+ENTRY(csky_cmpxchg)
+ USPTOKSP
+ mfcr a3, epc
+ INCTRAP a3
+
+ subi sp, 8
+ stw a3, (sp, 0)
+ mfcr a3, epsr
+ stw a3, (sp, 4)
+
+ psrset ee
+1:
+ ldex a3, (a2)
+ cmpne a0, a3
+ bt16 2f
+ mov a3, a1
+ stex a3, (a2)
+ bez a3, 1b
+2:
+ sync.is
+ mvc a0
+ ldw a3, (sp, 0)
+ mtcr a3, epc
+ ldw a3, (sp, 4)
+ mtcr a3, epsr
+ addi sp, 8
+ KSPTOUSP
+ rte
+END(csky_cmpxchg)
+#else
+ENTRY(csky_cmpxchg)
+ USPTOKSP
+ mfcr a3, epc
+ INCTRAP a3
+
+ subi sp, 8
+ stw a3, (sp, 0)
+ mfcr a3, epsr
+ stw a3, (sp, 4)
+
+ psrset ee
+1:
+ ldw a3, (a2)
+ cmpne a0, a3
+ bt16 3f
+2:
+ stw a1, (a2)
+3:
+ mvc a0
+ ldw a3, (sp, 0)
+ mtcr a3, epc
+ ldw a3, (sp, 4)
+ mtcr a3, epsr
+ addi sp, 8
+ KSPTOUSP
+ rte
+END(csky_cmpxchg)
+
+/*
+ * Called from tlbmodified exception
+ */
+ENTRY(csky_cmpxchg_fixup)
+ mfcr a0, epc
+ lrw a1, 2b
+ cmpne a1, a0
+ bt 1f
+ subi a1, (2b - 1b)
+ stw a1, (sp, LSAVE_PC)
+1:
+ rts
+END(csky_cmpxchg_fixup)
+#endif
+
--
2.7.4
\
 
 \ /
  Last update: 2018-07-01 19:33    [W:0.402 / U:0.052 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site