Diff: platform/CThunk.h
- Revision:
- 0:0e018d759a2a
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/platform/CThunk.h Tue Nov 08 18:27:11 2016 +0000
@@ -0,0 +1,245 @@
+
+/** \addtogroup platform */
+/** @{*/
+/* General C++ Object Thunking class
+ *
+ * - allows direct callbacks to non-static C++ class functions
+ * - keeps track for the corresponding class instance
+ * - supports an optional context parameter for the called function
+ * - ideally suited for class object receiving interrupts (NVIC_SetVector)
+ *
+ * Copyright (c) 2014-2015 ARM Limited
+ *
+ * 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.
+ */
+
+/* General C++ Object Thunking class
+ *
+ * - allows direct callbacks to non-static C++ class functions
+ * - keeps track for the corresponding class instance
+ * - supports an optional context parameter for the called function
+ * - ideally suited for class object receiving interrupts (NVIC_SetVector)
+ */
+
+#ifndef __CTHUNK_H__
+#define __CTHUNK_H__
+
+#define CTHUNK_ADDRESS 1
+#define CTHUNK_VARIABLES volatile uint32_t code[2]
+
+#if (defined(__CORTEX_M3) || defined(__CORTEX_M4) || defined(__CORTEX_M7) || defined(__CORTEX_A9))
+/**
+* CTHUNK disassembly for Cortex-M3/M4/M7/A9 (thumb2):
+* * adr r0, #4
+* * ldm r0, {r0, r1, r2, pc}
+*
+* This instruction loads the arguments for the static thunking function to r0-r2, and
+* branches to that function by loading its address into PC.
+*
+* This is safe for both regular calling and interrupt calling, since it only touches scratch registers
+* which should be saved by the caller, and are automatically saved as part of the IRQ context switch.
+*/
+#define CTHUNK_ASSIGMENT do { \
+ m_thunk.code[0] = 0xE890A001; \
+ m_thunk.code[1] = 0x00008007; \
+ } while (0)
+
+#elif (defined(__CORTEX_M0PLUS) || defined(__CORTEX_M0))
+/*
+* CTHUNK disassembly for Cortex M0/M0+ (thumb):
+* * adr r0, #4
+* * ldm r0, {r0, r1, r2, r3}
+* * bx r3
+*/
+#define CTHUNK_ASSIGMENT do { \
+ m_thunk.code[0] = 0xC80FA001; \
+ m_thunk.code[1] = 0x00004718; \
+ } while (0)
+
+#else
+#error "Target is not currently suported."
+#endif
+
+/* IRQ/Exception compatible thunk entry function */
+typedef void (*CThunkEntry)(void);
+
+/**
+ * Class for created a pointer with data bound to it
+ *
+ * @Note Synchronization level: Not protected
+ */
+template<class T>
+class CThunk
+{
+ public:
+ typedef void (T::*CCallbackSimple)(void);
+ typedef void (T::*CCallback)(void* context);
+
+ inline CThunk(T *instance)
+ {
+ init(instance, NULL, NULL);
+ }
+
+ inline CThunk(T *instance, CCallback callback)
+ {
+ init(instance, callback, NULL);
+ }
+
+ ~CThunk() {
+
+ }
+
+ inline CThunk(T *instance, CCallbackSimple callback)
+ {
+ init(instance, (CCallback)callback, NULL);
+ }
+
+ inline CThunk(T &instance, CCallback callback)
+ {
+ init(instance, callback, NULL);
+ }
+
+ inline CThunk(T &instance, CCallbackSimple callback)
+ {
+ init(instance, (CCallback)callback, NULL);
+ }
+
+ inline CThunk(T &instance, CCallback callback, void* context)
+ {
+ init(instance, callback, context);
+ }
+
+ inline void callback(CCallback callback)
+ {
+ m_callback = callback;
+ }
+
+ inline void callback(CCallbackSimple callback)
+ {
+ m_callback = (CCallback)callback;
+ }
+
+ inline void context(void* context)
+ {
+ m_thunk.context = (uint32_t)context;
+ }
+
+ inline void context(uint32_t context)
+ {
+ m_thunk.context = context;
+ }
+
+ inline uint32_t entry(void)
+ {
+ return (((uint32_t)&m_thunk)|CTHUNK_ADDRESS);
+ }
+
+ /* get thunk entry point for connecting rhunk to an IRQ table */
+ inline operator CThunkEntry(void)
+ {
+ return (CThunkEntry)entry();
+ }
+
+ /* get thunk entry point for connecting rhunk to an IRQ table */
+ inline operator uint32_t(void)
+ {
+ return entry();
+ }
+
+ /* simple test function */
+ inline void call(void)
+ {
+ (((CThunkEntry)(entry()))());
+ }
+
+ private:
+ T* m_instance;
+ volatile CCallback m_callback;
+
+// TODO: this needs proper fix, to refactor toolchain header file and all its use
+// PACKED there is not defined properly for IAR
+#if defined (__ICCARM__)
+ typedef __packed struct
+ {
+ CTHUNK_VARIABLES;
+ volatile uint32_t instance;
+ volatile uint32_t context;
+ volatile uint32_t callback;
+ volatile uint32_t trampoline;
+ } CThunkTrampoline;
+#else
+ typedef struct
+ {
+ CTHUNK_VARIABLES;
+ volatile uint32_t instance;
+ volatile uint32_t context;
+ volatile uint32_t callback;
+ volatile uint32_t trampoline;
+ } __attribute__((__packed__)) CThunkTrampoline;
+#endif
+
+ static void trampoline(T* instance, void* context, CCallback* callback)
+ {
+ if(instance && *callback) {
+ (static_cast<T*>(instance)->**callback)(context);
+ }
+ }
+
+ volatile CThunkTrampoline m_thunk;
+
+ inline void init(T *instance, CCallback callback, void* context)
+ {
+ /* remember callback - need to add this level of redirection
+ as pointer size for member functions differs between platforms */
+ m_callback = callback;
+
+ /* populate thunking trampoline */
+ CTHUNK_ASSIGMENT;
+ m_thunk.context = (uint32_t)context;
+ m_thunk.instance = (uint32_t)instance;
+ m_thunk.callback = (uint32_t)&m_callback;
+ m_thunk.trampoline = (uint32_t)&trampoline;
+
+#if defined(__CORTEX_A9)
+ /* Data cache clean */
+ /* Cache control */
+ {
+ uint32_t start_addr = (uint32_t)&m_thunk & 0xFFFFFFE0;
+ uint32_t end_addr = (uint32_t)&m_thunk + sizeof(m_thunk);
+ uint32_t addr;
+
+ /* Data cache clean and invalid */
+ for (addr = start_addr; addr < end_addr; addr += 0x20) {
+ __v7_clean_inv_dcache_mva((void *)addr);
+ }
+ /* Instruction cache invalid */
+ __v7_inv_icache_all();
+ __ca9u_inv_tlb_all();
+ __v7_inv_btac();
+ }
+#endif
+#if defined(__CORTEX_M7)
+ /* Data cache clean and invalid */
+ SCB_CleanInvalidateDCache();
+
+ /* Instruction cache invalid */
+ SCB_InvalidateICache();
+#endif
+ __ISB();
+ __DSB();
+ }
+};
+
+#endif/*__CTHUNK_H__*/
+
+/** @}*/