1 /*
2 * File : cpu.c
3 * This file is part of RT-Thread RTOS
4 * COPYRIGHT (C) 2006 - 2011, RT-Thread Development Team
5 *
6 * The license and distribution terms for this file may be
7 * found in the file LICENSE in this distribution or at
8 * http://www.rt-thread.org/license/LICENSE
9 *
10 * Change Logs:
11 * Date Author Notes
12 * 2010-05-17 swkyer first version
13 */
14 #include <rtthread.h>
15 #include <rthw.h>
16 #include "../common/exception.h"
17 #include "../common/mipsregs.h"
18
19 /**
20 * @addtogroup Loongson
21 */
22
23 /*@{*/
24
25 /**
26 * exception handle table
27 */
28 #define RT_EXCEPTION_MAX 8
29 exception_func_t sys_exception_handlers[RT_EXCEPTION_MAX];
30
31 /**
32 * setup the exception handle
33 */
rt_set_except_vector(int n,exception_func_t func)34 exception_func_t rt_set_except_vector(int n, exception_func_t func)
35 {
36 exception_func_t old_handler = sys_exception_handlers[n];
37
38 if ((n == 0) || (n > RT_EXCEPTION_MAX) || (!func))
39 {
40 return 0;
41 }
42
43 sys_exception_handlers[n] = func;
44
45 return old_handler;
46 }
47
tlb_refill_handler(void)48 void tlb_refill_handler(void)
49 {
50 rt_kprintf("tlb-miss happens, epc: 0x%08x\n", read_c0_epc());
51 rt_hw_cpu_shutdown();
52 }
53
cache_error_handler(void)54 void cache_error_handler(void)
55 {
56 rt_kprintf("cache exception happens, epc: 0x%08x\n", read_c0_epc());
57 rt_hw_cpu_shutdown();
58 }
59
unhandled_exception_handle(pt_regs_t * regs)60 static void unhandled_exception_handle(pt_regs_t *regs)
61 {
62 rt_kprintf("exception happens, epc: 0x%08x, cause: 0x%08x\n", regs->cp0_epc, read_c0_cause());
63 }
64
install_default_execpt_handle(void)65 void install_default_execpt_handle(void)
66 {
67 rt_int32_t i;
68
69 for (i=0; i<RT_EXCEPTION_MAX; i++)
70 sys_exception_handlers[i] = (exception_func_t)unhandled_exception_handle;
71 }
72
exception_handler(pt_regs_t * regs)73 void exception_handler(pt_regs_t *regs)
74 {
75 rt_uint32_t cause;
76 rt_uint32_t index;
77
78 cause = (read_c0_cause() & read_c0_config());
79 cause = (cause & 0xfc00) >> 8;
80
81 for (index = RT_EXCEPTION_MAX; index > 0; index --)
82 {
83 if (cause & (1 << index))
84 {
85 sys_exception_handlers[index](regs);
86 cause &= ~(1 << index);
87 }
88 }
89 }
90
91 /*@}*/
92