/* * File : cpuport.c * This file is part of RT-Thread RTOS * COPYRIGHT (C) 2009 - 2011, RT-Thread Development Team * * The license and distribution terms for this file may be * found in the file LICENSE in this distribution or at * http://www.rt-thread.org/license/LICENSE * * Change Logs: * Date Author Notes * 20011-05-23 aozima the first version for PIC32. * 20011-09-05 aozima merge all of C source code into cpuport.c. */ #include <rtthread.h> /** * @addtogroup PIC32 */ /*@{*/ /* exception and interrupt handler table */ rt_uint32_t rt_interrupt_from_thread, rt_interrupt_to_thread; rt_uint32_t rt_thread_switch_interrupt_flag; rt_uint32_t __attribute__((nomips16)) _get_gp(void) { rt_uint32_t result; // get the gp reg asm volatile("move %0, $28" : "=r"(result)); return result; } /** * This function will initialize thread stack * * @param tentry the entry of thread * @param parameter the parameter of entry * @param stack_addr the beginning stack address * @param texit the function will be called when thread exit * * @return stack address */ rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter, rt_uint8_t *stack_addr, void *texit) { rt_uint32_t *stk; /** Start at stack top */ stk = (rt_uint32_t *)stack_addr; *(stk) = (rt_uint32_t) tentry; /* pc: Entry Point */ *(--stk) = (rt_uint32_t) 0x00800000; /* c0_cause: IV=1, */ *(--stk) = (rt_uint32_t) 0; /* c0_badvaddr */ *(--stk) = (rt_uint32_t) 0; /* lo */ *(--stk) = (rt_uint32_t) 0; /* hi */ *(--stk) = (rt_uint32_t) 1; /* C0_SR: IE = En, */ *(--stk) = (rt_uint32_t) texit; /* 31 ra */ *(--stk) = (rt_uint32_t) 0x0000001e; /* 30 s8 */ *(--stk) = (rt_uint32_t) stack_addr; /* 29 sp */ *(--stk) = (rt_uint32_t) _get_gp(); /* 28 gp */ *(--stk) = (rt_uint32_t) 0x0000001b; /* 27 k1 */ *(--stk) = (rt_uint32_t) 0x0000001a; /* 26 k0 */ *(--stk) = (rt_uint32_t) 0x00000019; /* 25 t9 */ *(--stk) = (rt_uint32_t) 0x00000018; /* 24 t8 */ *(--stk) = (rt_uint32_t) 0x00000017; /* 23 s7 */ *(--stk) = (rt_uint32_t) 0x00000016; /* 22 s6 */ *(--stk) = (rt_uint32_t) 0x00000015; /* 21 s5 */ *(--stk) = (rt_uint32_t) 0x00000014; /* 20 s4 */ *(--stk) = (rt_uint32_t) 0x00000013; /* 19 s3 */ *(--stk) = (rt_uint32_t) 0x00000012; /* 18 s2 */ *(--stk) = (rt_uint32_t) 0x00000011; /* 17 s1 */ *(--stk) = (rt_uint32_t) 0x00000010; /* 16 s0 */ *(--stk) = (rt_uint32_t) 0x0000000f; /* 15 t7 */ *(--stk) = (rt_uint32_t) 0x0000000e; /* 14 t6 */ *(--stk) = (rt_uint32_t) 0x0000000d; /* 13 t5 */ *(--stk) = (rt_uint32_t) 0x0000000c; /* 12 t4 */ *(--stk) = (rt_uint32_t) 0x0000000b; /* 11 t3 */ *(--stk) = (rt_uint32_t) 0x0000000a; /* 10 t2 */ *(--stk) = (rt_uint32_t) 0x00000009; /* 9 t1 */ *(--stk) = (rt_uint32_t) 0x00000008; /* 8 t0 */ *(--stk) = (rt_uint32_t) 0x00000007; /* 7 a3 */ *(--stk) = (rt_uint32_t) 0x00000006; /* 6 a2 */ *(--stk) = (rt_uint32_t) 0x00000005; /* 5 a1 */ *(--stk) = (rt_uint32_t) parameter; /* 4 a0 */ *(--stk) = (rt_uint32_t) 0x00000003; /* 3 v1 */ *(--stk) = (rt_uint32_t) 0x00000002; /* 2 v0 */ *(--stk) = (rt_uint32_t) 0x00000001; /* 1 at */ *(--stk) = (rt_uint32_t) 0x00000000; /* 0 zero */ /* return task's current stack address */ return (rt_uint8_t *)stk; } /*@}*/