Diff: targets/TARGET_Realtek/TARGET_AMEBA/TARGET_RTL8195A/device/TOOLCHAIN_ARM_STD/sys.cpp

Revision:

167:e84263d55307

Child:

173:e131a1973e81

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_Realtek/TARGET_AMEBA/TARGET_RTL8195A/device/TOOLCHAIN_ARM_STD/sys.cpp	Wed Jun 21 17:46:44 2017 +0100
@@ -0,0 +1,52 @@
+/******************************************************************************
+ * Copyright (c) 2013-2016 Realtek Semiconductor Corp.
+ *
+ * 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.
+ *
+ ******************************************************************************
+ * mbed Microcontroller Library - stackheap
+ * Setup a fixed single stack/heap memory model, 
+ * between the top of the RW/ZI region and the stackpointer
+ ******************************************************************************/
+
+#ifdef __cplusplus
+extern "C" {
+#endif 
+
+#include <rt_misc.h>
+#include <stdint.h>
+
+extern char Image$$RW_IRAM1$$ZI$$Limit[];
+extern __value_in_regs struct __initial_stackheap __user_setup_stackheap(uint32_t R0, uint32_t R1, uint32_t R2, uint32_t R3) {
+    uint32_t zi_limit = (uint32_t)Image$$RW_IRAM1$$ZI$$Limit;
+    uint32_t sp_limit = __current_sp();
+
+    zi_limit = (zi_limit + 7) & ~0x7;    // ensure zi_limit is 8-byte aligned
+
+    //push down stack pointer to recycle some of the stack space that are not use in future
+    __asm volatile
+    (
+        "MRS  IP, MSP \n"
+        "ADD  IP, #64 \n"
+        "BIC   IP, IP, #7 \n"
+        "MSR  MSP, IP \n"
+    );
+    struct __initial_stackheap r;
+    r.heap_base = zi_limit;
+    r.heap_limit = sp_limit;
+    return r;
+}
+
+#ifdef __cplusplus
+}
+#endif