1 /*
2  * Copyright (c) 2006-2021, RT-Thread Development Team
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  *
6  * Change Logs:
7  * Date         Author      Notes
8  * 2009-01-05   Bernard     first version
9  * 2011-02-14   onelife     Modify for EFM32
10  * 2011-06-17   onelife     Merge all of the C source code into cpuport.c
11  * 2012-12-23   aozima      stack addr align to 8byte.
12  * 2012-12-29   Bernard     Add exception hook.
13  * 2013-07-09   aozima      enhancement hard fault exception handler.
14  * 2019-07-03   yangjie     add __rt_ffs() for armclang.
15  */
16 
17 #include <rtthread.h>
18 
19 struct exception_stack_frame
20 {
21     rt_uint32_t r0;
22     rt_uint32_t r1;
23     rt_uint32_t r2;
24     rt_uint32_t r3;
25     rt_uint32_t r12;
26     rt_uint32_t lr;
27     rt_uint32_t pc;
28     rt_uint32_t psr;
29 };
30 
31 struct stack_frame
32 {
33     /* r4 ~ r11 register */
34     rt_uint32_t r4;
35     rt_uint32_t r5;
36     rt_uint32_t r6;
37     rt_uint32_t r7;
38     rt_uint32_t r8;
39     rt_uint32_t r9;
40     rt_uint32_t r10;
41     rt_uint32_t r11;
42 
43     struct exception_stack_frame exception_stack_frame;
44 };
45 
46 /* flag in interrupt handling */
47 rt_uint32_t rt_interrupt_from_thread, rt_interrupt_to_thread;
48 rt_uint32_t rt_thread_switch_interrupt_flag;
49 /* exception hook */
50 static rt_err_t (*rt_exception_hook)(void *context) = RT_NULL;
51 
52 /**
53  * This function will initialize thread stack
54  *
55  * @param tentry the entry of thread
56  * @param parameter the parameter of entry
57  * @param stack_addr the beginning stack address
58  * @param texit the function will be called when thread exit
59  *
60  * @return stack address
61  */
rt_hw_stack_init(void * tentry,void * parameter,rt_uint8_t * stack_addr,void * texit)62 rt_uint8_t *rt_hw_stack_init(void       *tentry,
63                              void       *parameter,
64                              rt_uint8_t *stack_addr,
65                              void       *texit)
66 {
67     struct stack_frame *stack_frame;
68     rt_uint8_t         *stk;
69     unsigned long       i;
70 
71     stk  = stack_addr + sizeof(rt_uint32_t);
72     stk  = (rt_uint8_t *)RT_ALIGN_DOWN((rt_uint32_t)stk, 8);
73     stk -= sizeof(struct stack_frame);
74 
75     stack_frame = (struct stack_frame *)stk;
76 
77     /* init all register */
78     for (i = 0; i < sizeof(struct stack_frame) / sizeof(rt_uint32_t); i ++)
79     {
80         ((rt_uint32_t *)stack_frame)[i] = 0xdeadbeef;
81     }
82 
83     stack_frame->exception_stack_frame.r0  = (unsigned long)parameter; /* r0 : argument */
84     stack_frame->exception_stack_frame.r1  = 0;                        /* r1 */
85     stack_frame->exception_stack_frame.r2  = 0;                        /* r2 */
86     stack_frame->exception_stack_frame.r3  = 0;                        /* r3 */
87     stack_frame->exception_stack_frame.r12 = 0;                        /* r12 */
88     stack_frame->exception_stack_frame.lr  = (unsigned long)texit;     /* lr */
89     stack_frame->exception_stack_frame.pc  = (unsigned long)tentry;    /* entry point, pc */
90     stack_frame->exception_stack_frame.psr = 0x01000000L;              /* PSR */
91 
92     /* return task's current stack address */
93     return stk;
94 }
95 
96 /**
97  * This function set the hook, which is invoked on fault exception handling.
98  *
99  * @param exception_handle the exception handling hook function.
100  */
rt_hw_exception_install(rt_err_t (* exception_handle)(void * context))101 void rt_hw_exception_install(rt_err_t (*exception_handle)(void* context))
102 {
103     rt_exception_hook = exception_handle;
104 }
105 
106 #define SCB_CFSR        (*(volatile const unsigned *)0xE000ED28) /* Configurable Fault Status Register */
107 #define SCB_HFSR        (*(volatile const unsigned *)0xE000ED2C) /* HardFault Status Register */
108 #define SCB_MMAR        (*(volatile const unsigned *)0xE000ED34) /* MemManage Fault Address register */
109 #define SCB_BFAR        (*(volatile const unsigned *)0xE000ED38) /* Bus Fault Address Register */
110 #define SCB_AIRCR       (*(volatile unsigned long *)0xE000ED0C)  /* Reset control Address Register */
111 #define SCB_RESET_VALUE 0x05FA0004                               /* Reset value, write to SCB_AIRCR can reset cpu */
112 
113 #define SCB_CFSR_MFSR   (*(volatile const unsigned char*)0xE000ED28)  /* Memory-management Fault Status Register */
114 #define SCB_CFSR_BFSR   (*(volatile const unsigned char*)0xE000ED29)  /* Bus Fault Status Register */
115 #define SCB_CFSR_UFSR   (*(volatile const unsigned short*)0xE000ED2A) /* Usage Fault Status Register */
116 
117 #ifdef RT_USING_FINSH
usage_fault_track(void)118 static void usage_fault_track(void)
119 {
120     rt_kprintf("usage fault:\n");
121     rt_kprintf("SCB_CFSR_UFSR:0x%02X ", SCB_CFSR_UFSR);
122 
123     if(SCB_CFSR_UFSR & (1<<0))
124     {
125         /* [0]:UNDEFINSTR */
126         rt_kprintf("UNDEFINSTR ");
127     }
128 
129     if(SCB_CFSR_UFSR & (1<<1))
130     {
131         /* [1]:INVSTATE */
132         rt_kprintf("INVSTATE ");
133     }
134 
135     if(SCB_CFSR_UFSR & (1<<2))
136     {
137         /* [2]:INVPC */
138         rt_kprintf("INVPC ");
139     }
140 
141     if(SCB_CFSR_UFSR & (1<<3))
142     {
143         /* [3]:NOCP */
144         rt_kprintf("NOCP ");
145     }
146 
147     if(SCB_CFSR_UFSR & (1<<8))
148     {
149         /* [8]:UNALIGNED */
150         rt_kprintf("UNALIGNED ");
151     }
152 
153     if(SCB_CFSR_UFSR & (1<<9))
154     {
155         /* [9]:DIVBYZERO */
156         rt_kprintf("DIVBYZERO ");
157     }
158 
159     rt_kprintf("\n");
160 }
161 
bus_fault_track(void)162 static void bus_fault_track(void)
163 {
164     rt_kprintf("bus fault:\n");
165     rt_kprintf("SCB_CFSR_BFSR:0x%02X ", SCB_CFSR_BFSR);
166 
167     if(SCB_CFSR_BFSR & (1<<0))
168     {
169         /* [0]:IBUSERR */
170         rt_kprintf("IBUSERR ");
171     }
172 
173     if(SCB_CFSR_BFSR & (1<<1))
174     {
175         /* [1]:PRECISERR */
176         rt_kprintf("PRECISERR ");
177     }
178 
179     if(SCB_CFSR_BFSR & (1<<2))
180     {
181         /* [2]:IMPRECISERR */
182         rt_kprintf("IMPRECISERR ");
183     }
184 
185     if(SCB_CFSR_BFSR & (1<<3))
186     {
187         /* [3]:UNSTKERR */
188         rt_kprintf("UNSTKERR ");
189     }
190 
191     if(SCB_CFSR_BFSR & (1<<4))
192     {
193         /* [4]:STKERR */
194         rt_kprintf("STKERR ");
195     }
196 
197     if(SCB_CFSR_BFSR & (1<<7))
198     {
199         rt_kprintf("SCB->BFAR:%08X\n", SCB_BFAR);
200     }
201     else
202     {
203         rt_kprintf("\n");
204     }
205 }
206 
mem_manage_fault_track(void)207 static void mem_manage_fault_track(void)
208 {
209     rt_kprintf("mem manage fault:\n");
210     rt_kprintf("SCB_CFSR_MFSR:0x%02X ", SCB_CFSR_MFSR);
211 
212     if(SCB_CFSR_MFSR & (1<<0))
213     {
214         /* [0]:IACCVIOL */
215         rt_kprintf("IACCVIOL ");
216     }
217 
218     if(SCB_CFSR_MFSR & (1<<1))
219     {
220         /* [1]:DACCVIOL */
221         rt_kprintf("DACCVIOL ");
222     }
223 
224     if(SCB_CFSR_MFSR & (1<<3))
225     {
226         /* [3]:MUNSTKERR */
227         rt_kprintf("MUNSTKERR ");
228     }
229 
230     if(SCB_CFSR_MFSR & (1<<4))
231     {
232         /* [4]:MSTKERR */
233         rt_kprintf("MSTKERR ");
234     }
235 
236     if(SCB_CFSR_MFSR & (1<<7))
237     {
238         /* [7]:MMARVALID */
239         rt_kprintf("SCB->MMAR:%08X\n", SCB_MMAR);
240     }
241     else
242     {
243         rt_kprintf("\n");
244     }
245 }
246 
hard_fault_track(void)247 static void hard_fault_track(void)
248 {
249     if(SCB_HFSR & (1UL<<1))
250     {
251         /* [1]:VECTBL, Indicates hard fault is caused by failed vector fetch. */
252         rt_kprintf("failed vector fetch\n");
253     }
254 
255     if(SCB_HFSR & (1UL<<30))
256     {
257         /* [30]:FORCED, Indicates hard fault is taken because of bus fault,
258                         memory management fault, or usage fault. */
259         if(SCB_CFSR_BFSR)
260         {
261             bus_fault_track();
262         }
263 
264         if(SCB_CFSR_MFSR)
265         {
266             mem_manage_fault_track();
267         }
268 
269         if(SCB_CFSR_UFSR)
270         {
271             usage_fault_track();
272         }
273     }
274 
275     if(SCB_HFSR & (1UL<<31))
276     {
277         /* [31]:DEBUGEVT, Indicates hard fault is triggered by debug event. */
278         rt_kprintf("debug event\n");
279     }
280 }
281 #endif /* RT_USING_FINSH */
282 
283 struct exception_info
284 {
285     rt_uint32_t exc_return;
286     struct stack_frame stack_frame;
287 };
288 
289 /*
290  * fault exception handler
291  */
rt_hw_hard_fault_exception(struct exception_info * exception_info)292 void rt_hw_hard_fault_exception(struct exception_info * exception_info)
293 {
294 #if defined(RT_USING_FINSH) && defined(MSH_USING_BUILT_IN_COMMANDS)
295     extern long list_thread(void);
296 #endif
297     struct exception_stack_frame *exception_stack = &exception_info->stack_frame.exception_stack_frame;
298     struct stack_frame *context = &exception_info->stack_frame;
299 
300     if (rt_exception_hook != RT_NULL)
301     {
302         rt_err_t result;
303 
304         result = rt_exception_hook(exception_stack);
305         if (result == RT_EOK)
306             return;
307     }
308 
309     rt_kprintf("psr: 0x%08x\n", context->exception_stack_frame.psr);
310 
311     rt_kprintf("r00: 0x%08x\n", context->exception_stack_frame.r0);
312     rt_kprintf("r01: 0x%08x\n", context->exception_stack_frame.r1);
313     rt_kprintf("r02: 0x%08x\n", context->exception_stack_frame.r2);
314     rt_kprintf("r03: 0x%08x\n", context->exception_stack_frame.r3);
315     rt_kprintf("r04: 0x%08x\n", context->r4);
316     rt_kprintf("r05: 0x%08x\n", context->r5);
317     rt_kprintf("r06: 0x%08x\n", context->r6);
318     rt_kprintf("r07: 0x%08x\n", context->r7);
319     rt_kprintf("r08: 0x%08x\n", context->r8);
320     rt_kprintf("r09: 0x%08x\n", context->r9);
321     rt_kprintf("r10: 0x%08x\n", context->r10);
322     rt_kprintf("r11: 0x%08x\n", context->r11);
323     rt_kprintf("r12: 0x%08x\n", context->exception_stack_frame.r12);
324     rt_kprintf(" lr: 0x%08x\n", context->exception_stack_frame.lr);
325     rt_kprintf(" pc: 0x%08x\n", context->exception_stack_frame.pc);
326 
327     if(exception_info->exc_return & (1 << 2) )
328     {
329         rt_kprintf("hard fault on thread: %s\r\n\r\n", rt_thread_self()->parent.name);
330 
331 #if defined(RT_USING_FINSH) && defined(MSH_USING_BUILT_IN_COMMANDS)
332         list_thread();
333 #endif
334     }
335     else
336     {
337         rt_kprintf("hard fault on handler\r\n\r\n");
338     }
339 
340 #ifdef RT_USING_FINSH
341     hard_fault_track();
342 #endif /* RT_USING_FINSH */
343 
344     while (1);
345 }
346 
347 /**
348  * reset CPU
349  */
rt_hw_cpu_reset(void)350 void rt_hw_cpu_reset(void)
351 {
352     SCB_AIRCR = SCB_RESET_VALUE;
353 }
354 
355 #ifdef RT_USING_CPU_FFS
356 /**
357  * This function finds the first bit set (beginning with the least significant bit)
358  * in value and return the index of that bit.
359  *
360  * Bits are numbered starting at 1 (the least significant bit).  A return value of
361  * zero from any of these functions means that the argument was zero.
362  *
363  * @return return the index of the first bit set. If value is 0, then this function
364  * shall return 0.
365  */
366 #if defined(__CC_ARM)
__rt_ffs(int value)367 __asm int __rt_ffs(int value)
368 {
369     CMP     r0, #0x00
370     BEQ     exit
371 
372     RBIT    r0, r0
373     CLZ     r0, r0
374     ADDS    r0, r0, #0x01
375 
376 exit
377     BX      lr
378 }
379 #elif defined(__clang__)
__rt_ffs(int value)380 int __rt_ffs(int value)
381 {
382     __asm volatile(
383         "CMP     %1, #0x00            \n"
384         "BEQ     1f                   \n"
385 
386         "RBIT    %1, %1               \n"
387         "CLZ     %0, %1               \n"
388         "ADDS    %0, %0, #0x01        \n"
389 
390         "1:                           \n"
391 
392         : "=r"(value)
393         : "r"(value)
394     );
395     return value;
396 }
397 #elif defined(__IAR_SYSTEMS_ICC__)
__rt_ffs(int value)398 int __rt_ffs(int value)
399 {
400     if (value == 0) return value;
401 
402     asm("RBIT %0, %1" : "=r"(value) : "r"(value));
403     asm("CLZ  %0, %1" : "=r"(value) : "r"(value));
404     asm("ADDS %0, %1, #0x01" : "=r"(value) : "r"(value));
405 
406     return value;
407 }
408 #elif defined(__GNUC__)
__rt_ffs(int value)409 int __rt_ffs(int value)
410 {
411     return __builtin_ffs(value);
412 }
413 #endif
414 
415 #endif
416