added SuperH atomic support to libcutils

3 files changed, 167 insertions, 0 deletions

diff --git a/libcutils/Android.mk b/libcutils/Android.mk
index 98e59eee3..30f4a49ed 100644
--- a/libcutils/Android.mk
+++ b/libcutils/Android.mk
@@ -98,7 +98,11 @@ LOCAL_SRC_FILES := $(commonSources) ashmem-dev.c mq.c
 ifeq ($(TARGET_ARCH),arm)
 LOCAL_SRC_FILES += memset32.S atomic-android-arm.S
 else  # !arm
+ifeq ($(TARGET_ARCH),sh)
+LOCAL_SRC_FILES += memory.c atomic-android-sh.c
+else  # !sh
 LOCAL_SRC_FILES += memory.c
+endif # !sh
 endif # !arm
 
 LOCAL_C_INCLUDES := $(KERNEL_HEADERS)
diff --git a/libcutils/atomic-android-sh.c b/libcutils/atomic-android-sh.c
new file mode 100644
index 000000000..acbea976d
--- /dev/null
+++ b/libcutils/atomic-android-sh.c
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2007 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <cutils/atomic.h>
+#ifdef HAVE_WIN32_THREADS
+#include <windows.h>
+#else
+#include <sched.h>
+#endif
+
+/*
+ * Note :
+ *
+ * (1) SuperH does not have CMPXCHG.  It has only TAS for atomic
+ *     operations.  It does not seem a good idea to implement CMPXCHG,
+ *     with TAS.  So, we choose to implemnt these operations with
+ *     posix mutexes.  Please be sure that this might cause performance
+ *     problem for Android-SH. Using LL/SC instructions supported in SH-X3,
+ *     best performnace would be realized.
+ *
+ * (2) Mutex initialization problem happens, which is commented for
+ *     ARM implementation, in this file above.
+ *     We follow the fact that the initializer for mutex is a simple zero
+ *     value.
+ */
+
+#include <pthread.h>
+
+#define  SWAP_LOCK_COUNT  32U
+static pthread_mutex_t  _swap_locks[SWAP_LOCK_COUNT];
+
+#define  SWAP_LOCK(addr)   \
+   &_swap_locks[((unsigned)(void*)(addr) >> 3U) % SWAP_LOCK_COUNT]
+
+
+void android_atomic_write(int32_t value, volatile int32_t* addr) {
+    int32_t oldValue;
+    do {
+        oldValue = *addr;
+    } while (android_atomic_cmpxchg(oldValue, value, addr));
+}
+
+int32_t android_atomic_inc(volatile int32_t* addr) {
+    int32_t oldValue;
+    do {
+        oldValue = *addr;
+    } while (android_atomic_cmpxchg(oldValue, oldValue+1, addr));
+    return oldValue;
+}
+
+int32_t android_atomic_dec(volatile int32_t* addr) {
+    int32_t oldValue;
+    do {
+        oldValue = *addr;
+    } while (android_atomic_cmpxchg(oldValue, oldValue-1, addr));
+    return oldValue;
+}
+
+int32_t android_atomic_add(int32_t value, volatile int32_t* addr) {
+    int32_t oldValue;
+    do {
+        oldValue = *addr;
+    } while (android_atomic_cmpxchg(oldValue, oldValue+value, addr));
+    return oldValue;
+}
+
+int32_t android_atomic_and(int32_t value, volatile int32_t* addr) {
+    int32_t oldValue;
+    do {
+        oldValue = *addr;
+    } while (android_atomic_cmpxchg(oldValue, oldValue&value, addr));
+    return oldValue;
+}
+
+int32_t android_atomic_or(int32_t value, volatile int32_t* addr) {
+    int32_t oldValue;
+    do {
+        oldValue = *addr;
+    } while (android_atomic_cmpxchg(oldValue, oldValue|value, addr));
+    return oldValue;
+}
+
+int32_t android_atomic_swap(int32_t value, volatile int32_t* addr) {
+    int32_t oldValue;
+    do {
+        oldValue = *addr;
+    } while (android_atomic_cmpxchg(oldValue, value, addr));
+    return oldValue;
+}
+
+int android_atomic_cmpxchg(int32_t oldvalue, int32_t newvalue,
+                           volatile int32_t* addr) {
+    int result;
+    pthread_mutex_t*  lock = SWAP_LOCK(addr);
+
+    pthread_mutex_lock(lock);
+
+    if (*addr == oldvalue) {
+        *addr  = newvalue;
+        result = 0;
+    } else {
+        result = 1;
+    }
+    pthread_mutex_unlock(lock);
+    return result;
+}
+
+int64_t android_quasiatomic_swap_64(int64_t value, volatile int64_t* addr) {
+    int64_t oldValue;
+    pthread_mutex_t*  lock = SWAP_LOCK(addr);
+
+    pthread_mutex_lock(lock);
+
+    oldValue = *addr;
+    *addr    = value;
+
+    pthread_mutex_unlock(lock);
+    return oldValue;
+}
+
+int android_quasiatomic_cmpxchg_64(int64_t oldvalue, int64_t newvalue,
+        volatile int64_t* addr) {
+    int result;
+    pthread_mutex_t*  lock = SWAP_LOCK(addr);
+
+    pthread_mutex_lock(lock);
+
+    if (*addr == oldvalue) {
+        *addr  = newvalue;
+        result = 0;
+    } else {
+        result = 1;
+    }
+    pthread_mutex_unlock(lock);
+    return result;
+}
+
+int64_t android_quasiatomic_read_64(volatile int64_t* addr) {
+    int64_t result;
+    pthread_mutex_t*  lock = SWAP_LOCK(addr);
+
+    pthread_mutex_lock(lock);
+    result = *addr;
+    pthread_mutex_unlock(lock);
+    return result;
+}
diff --git a/libcutils/atomic.c b/libcutils/atomic.c
index 65d7af0af..41faaa282 100644
--- a/libcutils/atomic.c
+++ b/libcutils/atomic.c
@@ -245,6 +245,10 @@ int64_t android_quasiatomic_read_64(volatile int64_t* addr) {
     return result;
 }    
 
+/*****************************************************************************/
+#elif __sh__
+// implementation for SuperH is in atomic-android-sh.c.
+
 #else
 
 #error "Unsupported atomic operations for this platform"