From fdec7bc0a353346be482b7caf48408a4e28c14a1 Mon Sep 17 00:00:00 2001 From: "Ben V. Brown" Date: Sun, 8 Nov 2020 22:10:43 +1100 Subject: [PATCH] Collapse asm into one file Working across 4 files was a pain to figure out _exactly_ what was used. Collapsed all into one file for ease --- .../TS100/Core/BSP/Pine64/N200/portasm.S | 538 ++++++++++++++---- .../BSP/Pine64/Vendor/Lib/intexc_gd32vf103.S | 35 -- .../Core/BSP/Pine64/Vendor/RISCV/entry.S | 291 ---------- .../Core/BSP/Pine64/Vendor/RISCV/start.S | 289 ---------- 4 files changed, 416 insertions(+), 737 deletions(-) delete mode 100644 workspace/TS100/Core/BSP/Pine64/Vendor/Lib/intexc_gd32vf103.S delete mode 100644 workspace/TS100/Core/BSP/Pine64/Vendor/RISCV/entry.S delete mode 100644 workspace/TS100/Core/BSP/Pine64/Vendor/RISCV/start.S diff --git a/workspace/TS100/Core/BSP/Pine64/N200/portasm.S b/workspace/TS100/Core/BSP/Pine64/N200/portasm.S index 8e34bedb..ff73e533 100644 --- a/workspace/TS100/Core/BSP/Pine64/N200/portasm.S +++ b/workspace/TS100/Core/BSP/Pine64/N200/portasm.S @@ -2,11 +2,6 @@ #include "riscv_bits.h" #include "n200_timer.h" #include "n200_eclic.h" -#include "riscv_encoding.h" -#include "riscv_bits.h" -#include "n200_timer.h" -#include "n200_eclic.h" - #define USE_MSP 1 //启用中断栈 @@ -19,8 +14,295 @@ .global vPortEndScheduler .global vPortAsmAssertSP + .section .init + + .weak eclic_msip_handler //弱定义函数，这些在编译为bin后可以看到将全部为0 + .weak eclic_mtip_handler + .weak eclic_bwei_handler + .weak eclic_pmovi_handler + .weak WWDGT_IRQHandler + .weak LVD_IRQHandler + .weak TAMPER_IRQHandler + .weak RTC_IRQHandler + .weak FMC_IRQHandler + .weak RCU_IRQHandler + .weak EXTI0_IRQHandler + .weak EXTI1_IRQHandler + .weak EXTI2_IRQHandler + .weak EXTI3_IRQHandler + .weak EXTI4_IRQHandler + .weak DMA0_Channel0_IRQHandler + .weak DMA0_Channel1_IRQHandler + .weak DMA0_Channel2_IRQHandler + .weak DMA0_Channel3_IRQHandler + .weak DMA0_Channel4_IRQHandler + .weak DMA0_Channel5_IRQHandler + .weak DMA0_Channel6_IRQHandler + .weak ADC0_1_IRQHandler + .weak CAN0_TX_IRQHandler + .weak CAN0_RX0_IRQHandler + .weak CAN0_RX1_IRQHandler + .weak CAN0_EWMC_IRQHandler + .weak EXTI5_9_IRQHandler + .weak TIMER0_BRK_IRQHandler + .weak TIMER0_UP_IRQHandler + .weak TIMER0_TRG_CMT_IRQHandler + .weak TIMER0_Channel_IRQHandler + .weak TIMER1_IRQHandler + .weak TIMER2_IRQHandler + .weak TIMER3_IRQHandler + .weak I2C0_EV_IRQHandler + .weak I2C0_ER_IRQHandler + .weak I2C1_EV_IRQHandler + .weak I2C1_ER_IRQHandler + .weak SPI0_IRQHandler + .weak SPI1_IRQHandler + .weak USART0_IRQHandler + .weak USART1_IRQHandler + .weak USART2_IRQHandler + .weak EXTI10_15_IRQHandler + .weak RTC_Alarm_IRQHandler + .weak USBFS_WKUP_IRQHandler + .weak EXMC_IRQHandler + .weak TIMER4_IRQHandler + .weak SPI2_IRQHandler + .weak UART3_IRQHandler + .weak UART4_IRQHandler + .weak TIMER5_IRQHandler + .weak TIMER6_IRQHandler + .weak DMA1_Channel0_IRQHandler + .weak DMA1_Channel1_IRQHandler + .weak DMA1_Channel2_IRQHandler + .weak DMA1_Channel3_IRQHandler + .weak DMA1_Channel4_IRQHandler + .weak CAN1_TX_IRQHandler + .weak CAN1_RX0_IRQHandler + .weak CAN1_RX1_IRQHandler + .weak CAN1_EWMC_IRQHandler + .weak USBFS_IRQHandler + +vector_base: //中断向量表 + j _start //第一条指令即跳转到_start处开始执行 + .align 2 + .word 0 + .word 0 + .word eclic_msip_handler + .word 0 + .word 0 + .word 0 + .word eclic_mtip_handler + .word 0 + .word 0 + .word 0 + .word 0 + .word 0 + .word 0 + .word 0 + .word 0 + .word 0 + .word eclic_bwei_handler + .word eclic_pmovi_handler + .word WWDGT_IRQHandler + .word LVD_IRQHandler + .word TAMPER_IRQHandler + .word RTC_IRQHandler + .word FMC_IRQHandler + .word RCU_IRQHandler + .word EXTI0_IRQHandler + .word EXTI1_IRQHandler + .word EXTI2_IRQHandler + .word EXTI3_IRQHandler + .word EXTI4_IRQHandler + .word DMA0_Channel0_IRQHandler + .word DMA0_Channel1_IRQHandler + .word DMA0_Channel2_IRQHandler + .word DMA0_Channel3_IRQHandler + .word DMA0_Channel4_IRQHandler + .word DMA0_Channel5_IRQHandler + .word DMA0_Channel6_IRQHandler + .word ADC0_1_IRQHandler + .word CAN0_TX_IRQHandler + .word CAN0_RX0_IRQHandler + .word CAN0_RX1_IRQHandler + .word CAN0_EWMC_IRQHandler + .word EXTI5_9_IRQHandler + .word TIMER0_BRK_IRQHandler + .word TIMER0_UP_IRQHandler + .word TIMER0_TRG_CMT_IRQHandler + .word TIMER0_Channel_IRQHandler + .word TIMER1_IRQHandler + .word TIMER2_IRQHandler + .word TIMER3_IRQHandler + .word I2C0_EV_IRQHandler + .word I2C0_ER_IRQHandler + .word I2C1_EV_IRQHandler + .word I2C1_ER_IRQHandler + .word SPI0_IRQHandler + .word SPI1_IRQHandler + .word USART0_IRQHandler + .word USART1_IRQHandler + .word USART2_IRQHandler + .word EXTI10_15_IRQHandler + .word RTC_Alarm_IRQHandler + .word USBFS_WKUP_IRQHandler + .word 0 + .word 0 + .word 0 + .word 0 + .word 0 + .word EXMC_IRQHandler + .word 0 + .word TIMER4_IRQHandler + .word SPI2_IRQHandler + .word UART3_IRQHandler + .word UART4_IRQHandler + .word TIMER5_IRQHandler + .word TIMER6_IRQHandler + .word DMA1_Channel0_IRQHandler + .word DMA1_Channel1_IRQHandler + .word DMA1_Channel2_IRQHandler + .word DMA1_Channel3_IRQHandler + .word DMA1_Channel4_IRQHandler + .word 0 + .word 0 + .word CAN1_TX_IRQHandler + .word CAN1_RX0_IRQHandler + .word CAN1_RX1_IRQHandler + .word CAN1_EWMC_IRQHandler + .word USBFS_IRQHandler + + .globl _start + .type _start,@function + +_start: + + csrc CSR_MSTATUS, MSTATUS_MIE //CSR_MSTATUS &= ~0x8 mstatus[3]:0屏蔽全部中断 1不屏蔽全部中断 （当然这里全部中断是除过不可屏蔽中断） + /* Jump to logical address first to ensure correct operation of RAM region */ + la a0, _start //a0 = _start + li a1, 1 //a1 = 1 + slli a1, a1, 29 //a1 = 0x20000000 raw起始地址 + bleu a1, a0, _start0800 //if( a1 <= a0 ) JUMP _start0800 + srli a1, a1, 2 //a1 = 0x08000000 flash起始地址 + bleu a1, a0, _start0800 //if( a1 <= a0 ) JUMP _start0800 + la a0, _start0800 //a0 = _start0800 + add a0, a0, a1 //a0 = a0+a1 + jr a0 //JUMP a0 + +_start0800: + + /* Set the the NMI base to share with mtvec by setting CSR_MMISC_CTL */ + li t0, 0x200 //t0 = 0x200 + csrs CSR_MMISC_CTL, t0 //mmisc_ctl |= 0x200 CSR_MMISC_CTL[9]：设置NMI的地址与mtvec相同且，mcause.EXCCODE = 0xfff + //cs开头的指令是特有的用来操作内核寄存器的的指令，内核寄存器是一组特有的12位地址 + + /* Intial the mtvt*/ + la t0, vector_base //t0 = vector_base 向量表地址 + csrw CSR_MTVT, t0 //mtvt = vector_base 中断向量表基地址 + + /* Intial the mtvt2 and enable it*/ + la t0, irq_entry //t0 = irq_entry irq_entry定义在entry.S,有freertos操作系统情况下定义在portasm.S + csrw CSR_MTVT2, t0 //mtvt2 = irq_entry mtvt2[31:2]: 中断入口函数地址 + csrs CSR_MTVT2, 0x1 //mtvt2 |= 0x1 mtvt2[0]: 1配置mtvt2的配置有效，配0则为mtvec内地址 + + /* Intial the CSR MTVEC for the Trap ane NMI base addr*/ + la t0, trap_entry //t0 = trap_entry trap_entry定义在entry.S,有freertos操作系统情况下定义在portasm.S + csrw CSR_MTVEC, t0 //mtvec = trap_entry mtvec[31:6]：异常入口地址 + // mtvec[5:0]：0B00011 -- ECLIC中断模式 其他：默认模式 + // 这里配置为默认模式 + // trap_entry基本上可以理解为arm里的hard/mem/use/svc等fault了， + // 这里在移植freertos时就使用了 ecall 进入trap_entry里 相当于arm里的PendSVC + + /* OS启动前配置中断栈为FHEAP的end地址 */ + la t0, ucHeap + csrw CSR_MSCRATCH, t0 + +#ifdef __riscv_flen //浮点宏 + /* Enable FPU */ + li t0, MSTATUS_FS //t0 = 0x6000 + csrs mstatus, t0 //mstatus |= 0x6000 mstatus[14:13]:非零值启用浮点单元，配置为1或2会在第一次使用浮点单元时变为3，这里直接配置为3 + csrw fcsr, x0 //fcsr = x0 = 0 ??这里x0是否指的是zero通用寄存器值? 这个寄存器0-4位是浮点异常状态标志，5-7位是浮点舍入模式配置 +#endif + +.option push +.option norelax + la gp, __global_pointer$ //__global_pointer$定义在link连接脚本内，指向所有.data段后偏移0x800的地址,0x800为2K，其值源于下文解释 + //gp 意为global pointer （全局指针）寄存器是一个解决方案， + //为了以进一步优化存储器访问单个4KB区域内。 + //链接器使用__global_pointer$符号定义来比较内存地址，如果在范围内， + //则它将绝对/相对pc寻址替换为gp相对寻址，从而使代码更有效。这个过程通过-Wl,--no-relax选项使用。 + //这里.option norelax起到-Wl,--no-relax作用，就不需要在编译选项添加了 + //上文参考自：https://gnu-mcu-eclipse.github.io/arch/riscv/programmer/#the-gp-global-pointer-register + //要让 relaxing 优化起作用，编译时要加入 -msmall-data-limit=n 参数，有了这个参数， + //编译器会把内存空间小于 n 字节的静态变量放入 .sdata 或者 .sdata.* 节， + //然后链接器将这部分静态变量集中在 __global_pointer$ +/- 2K 的范围内。 + //上文参考自：https://blog.csdn.net/zoomdy/article/details/100703451 +.option pop + la sp, _sp //sp = 主栈栈顶地址 _sp定义在link连接脚本内 + + /* Load data section */ + la a0, _data_lma //a0 = data的Load Memory Address _data_lma定义在link连接脚本内 + la a1, _data //a1 = data的Run Memory Address _data定义在link连接脚本内 + la a2, _edata //a2 = data的Run Memory Address结束地址 _edata定义在link连接脚本内 + bgeu a1, a2, 2f //if( a1 >= a2 ) JUMP 2f 原则上不会出现_data地址大于_edata地址 + //如果出现了则直接跳转到 2f 即下一个2标签 +1: + lw t0, (a0) //t0 = _data_lma + sw t0, (a1) //*_data = t0 即 *_data_lma，按word写入 + addi a0, a0, 4 //a0 = a0 + 4 下一个ward + addi a1, a1, 4 //a1 = a1 + 4 + bltu a1, a2, 1b //if( a1 < a2 ) JUMP 1b 如果未到达_edata则跳转到 1b 即上一个1标签，这里会完成一个循环 +2: + /* Clear bss section */ + la a0, __bss_start //a0 = __bss_start 初值为0的全局变量段起始地址 __bss_start定义在link连接脚本内 + la a1, _end //a1 = _end 初值为0的全局变量段结束地址 _end定义在link连接脚本内 + bgeu a0, a1, 2f //if( a0 >= a1 ) JUMP 2f 原则上不会出现__bss_start地址大于_end地址 + //如果出现了则直接跳转到 2f 即下一个2标签 +1: + sw zero, (a0) //*__bss_start = zero = 0 bss段清除为0 + addi a0, a0, 4 //a0 = a0 + 4 下一个ward + bltu a0, a1, 1b //if( a0 < a1 ) JUMP 1b 如果未到达_end则跳转到 1b 即上一个1标签，这里会完成一个循环 + + //程序执行到这里全局变量就以及处理完毕了 +2: + /*enable mcycle_minstret*/ + csrci CSR_MCOUNTINHIBIT, 0x5 //CSR_MCOUNTINHIBIT &= ~0x5 这里清零了第0bit和第1bit，使能了mcycle计数和minstret计数 + //csrci这条指令处理立即数5bit，列如0x5只是0B00101，高位不处理 + /* + * Call vendor defined SystemInit to + * initialize the micro-controller system + */ + call SystemInit + /* Call global constructors */ + la a0, __libc_fini_array //a0 = __libc_fini_array newlib中atexit函数的参数 + call atexit //调用newlib中的 void atexit(void (*func)(void)) 函数 + //功能为注册main函数结束后调用的函数，这里是__libc_fini_array + call __libc_init_array //调用newlib中的 void __libc_init_array (void) 函数 + //这里要注意__libc_init_array函数会调用_init的钩子函数，用来做c环境初始化前的一些硬件初始化 + //列如时钟的配置等，这里_init定义在init.c + + //程序执行到这里C/C++环境就初始化完成了，可以进入main函数入口了 + /* argc = argv = 0 */ + li a0, 0 //a0 = 0 main函数参数argc = 0 + li a1, 0 //a1 = 0 main函数参数argv = 0 + call main //调用 int main(int argc,char **argv) 函数 + tail exit //main返回后调用newlib的exit函数, tail指令应该是不会返回的调用函数了 + +1: + j 1b //1b 即上一次1标签，即跳转到自己，程序到这里就死循环了，原则不会运行到这里 + + .global disable_mcycle_minstret +disable_mcycle_minstret: + csrsi CSR_MCOUNTINHIBIT, 0x5 //关闭了mcycle计数和minstret计数 + ret + + .global enable_mcycle_minstret +enable_mcycle_minstret: + csrci CSR_MCOUNTINHIBIT, 0x5 //使能了mcycle计数和minstret计数 + ret + + /** - * @brife 压栈通用寄存器 + * @brief 压栈通用寄存器 * @param x 目标sp寄存器 */ .macro pushREGFILE x @@ -31,8 +313,8 @@ #endif STORE x1, 1 * REGBYTES(\x) STORE x2, 2 * REGBYTES(\x) - //STORE x3, 3 * REGBYTES(\x) - //STORE x4, 4 * REGBYTES(\x) + #STORE x3, 3 * REGBYTES(\x) + #STORE x4, 4 * REGBYTES(\x) STORE x5, 5 * REGBYTES(\x) STORE x6, 6 * REGBYTES(\x) STORE x7, 7 * REGBYTES(\x) @@ -66,7 +348,7 @@ /** - * @brife 压栈csr寄存器(CSR_MSTATUS CSR_MEPC CSR_MSUBM CSR_MCAUSE) + * @brief 压栈csr寄存器（CSR_MSTATUS、CSR_MEPC、CSR_MSUBM、CSR_MCAUSE） * @param x 目标sp寄存器 */ .macro portSAVE_CONTEXT_EXCP x @@ -82,7 +364,109 @@ /** - * @brife 压栈浮点寄存器 + * @brief 压栈浮点寄存器 + * @param x 目标sp寄存器 + */ +.macro popVFPREGFILE x + flw f0, 36 * REGBYTES(\x) + flw f1, 37 * REGBYTES(\x) + flw f2, 38 * REGBYTES(\x) + flw f3, 39 * REGBYTES(\x) + flw f4, 40 * REGBYTES(\x) + flw f5, 41 * REGBYTES(\x) + flw f6, 42 * REGBYTES(\x) + flw f7, 43 * REGBYTES(\x) + flw f8, 44 * REGBYTES(\x) + flw f9, 45 * REGBYTES(\x) + flw f10,46 * REGBYTES(\x) + flw f11, 47 * REGBYTES(\x) + flw f12, 48 * REGBYTES(\x) + flw f13, 49 * REGBYTES(\x) + flw f14, 50 * REGBYTES(\x) + flw f15, 51 * REGBYTES(\x) + flw f16, 52 * REGBYTES(\x) + flw f17, 53 * REGBYTES(\x) + flw f18, 54 * REGBYTES(\x) + flw f19, 55 * REGBYTES(\x) + flw f20, 56 * REGBYTES(\x) + flw f21, 57 * REGBYTES(\x) + flw f22, 58 * REGBYTES(\x) + flw f23, 59 * REGBYTES(\x) + flw f24, 60 * REGBYTES(\x) + flw f25, 61 * REGBYTES(\x) + flw f26, 62 * REGBYTES(\x) + flw f27, 63 * REGBYTES(\x) + flw f28, 64 * REGBYTES(\x) + flw f29, 65 * REGBYTES(\x) + flw f30, 66 * REGBYTES(\x) + flw f31, 67 * REGBYTES(\x) +.endm + + +/** + * @brief 出栈通用寄存器 + * @param x 目标sp寄存器 + */ +.macro popREGFILE x + LOAD x1, 1 * REGBYTES(\x) + #LOAD x2, 2 * REGBYTES(\x) + #LOAD x3, 3 * REGBYTES(\x) + #LOAD x4, 4 * REGBYTES(\x) + LOAD x5, 5 * REGBYTES(\x) + LOAD x6, 6 * REGBYTES(\x) + LOAD x7, 7 * REGBYTES(\x) + LOAD x8, 8 * REGBYTES(\x) + LOAD x9, 9 * REGBYTES(\x) + LOAD x10, 10 * REGBYTES(\x) + LOAD x11, 11 * REGBYTES(\x) + LOAD x12, 12 * REGBYTES(\x) + LOAD x13, 13 * REGBYTES(\x) + LOAD x14, 14 * REGBYTES(\x) + LOAD x15, 15 * REGBYTES(\x) +#ifndef __riscv_32e + LOAD x16, 16 * REGBYTES(\x) + LOAD x17, 17 * REGBYTES(\x) + LOAD x18, 18 * REGBYTES(\x) + LOAD x19, 19 * REGBYTES(\x) + LOAD x20, 20 * REGBYTES(\x) + LOAD x21, 21 * REGBYTES(\x) + LOAD x22, 22 * REGBYTES(\x) + LOAD x23, 23 * REGBYTES(\x) + LOAD x24, 24 * REGBYTES(\x) + LOAD x25, 25 * REGBYTES(\x) + LOAD x26, 26 * REGBYTES(\x) + LOAD x27, 27 * REGBYTES(\x) + LOAD x28, 28 * REGBYTES(\x) + LOAD x29, 29 * REGBYTES(\x) + LOAD x30, 30 * REGBYTES(\x) + LOAD x31, 31 * REGBYTES(\x) +#endif +#ifdef __riscv_flen + addi \x, \x, REGBYTES * 68 //36+32 +#else + addi \x, \x, REGBYTES * 36 +#endif +.endm + + +/** + * @brief 出栈csr寄存器（CSR_MSTATUS、CSR_MEPC、CSR_MSUBM、CSR_MCAUSE） + * @param x 目标sp寄存器 + */ +.macro portRESTORE_CONTEXT_EXCP x + LOAD t0, 35*REGBYTES(\x) + csrw CSR_MCAUSE, t0 + LOAD t0, 34*REGBYTES(\x) + csrw CSR_MSUBM, t0 + LOAD t0, 33*REGBYTES(\x) + csrw CSR_MEPC, t0 + LOAD t0, 32*REGBYTES(\x) + csrw CSR_MSTATUS, t0 +.endm + + +/** + * @brief 出栈浮点寄存器 * @param x 目标sp寄存器 */ .macro pushVFPREGFILE x @@ -122,139 +506,40 @@ /** - * @brife 出栈通用寄存器 - * @param x 目标sp寄存器 - */ -.macro popREGFILE x - LOAD x1, 1 * REGBYTES(\x) - //LOAD x2, 2 * REGBYTES(\x) - //LOAD x3, 3 * REGBYTES(\x) - //LOAD x4, 4 * REGBYTES(\x) - LOAD x5, 5 * REGBYTES(\x) - LOAD x6, 6 * REGBYTES(\x) - LOAD x7, 7 * REGBYTES(\x) - LOAD x8, 8 * REGBYTES(\x) - LOAD x9, 9 * REGBYTES(\x) - LOAD x10, 10 * REGBYTES(\x) - LOAD x11, 11 * REGBYTES(\x) - LOAD x12, 12 * REGBYTES(\x) - LOAD x13, 13 * REGBYTES(\x) - LOAD x14, 14 * REGBYTES(\x) - LOAD x15, 15 * REGBYTES(\x) -#ifndef __riscv_32e - LOAD x16, 16 * REGBYTES(\x) - LOAD x17, 17 * REGBYTES(\x) - LOAD x18, 18 * REGBYTES(\x) - LOAD x19, 19 * REGBYTES(\x) - LOAD x20, 20 * REGBYTES(\x) - LOAD x21, 21 * REGBYTES(\x) - LOAD x22, 22 * REGBYTES(\x) - LOAD x23, 23 * REGBYTES(\x) - LOAD x24, 24 * REGBYTES(\x) - LOAD x25, 25 * REGBYTES(\x) - LOAD x26, 26 * REGBYTES(\x) - LOAD x27, 27 * REGBYTES(\x) - LOAD x28, 28 * REGBYTES(\x) - LOAD x29, 29 * REGBYTES(\x) - LOAD x30, 30 * REGBYTES(\x) - LOAD x31, 31 * REGBYTES(\x) -#endif -#ifdef __riscv_flen - addi \x, \x, REGBYTES * 68 //36+32 -#else - addi \x, \x, REGBYTES * 36 -#endif -.endm - - -/** - * @brife 出栈csr寄存器(CSR_MSTATUS CSR_MEPC CSR_MSUBM CSR_MCAUSE) - * @param x 目标sp寄存器 - */ -.macro portRESTORE_CONTEXT_EXCP x - LOAD t0, 35 * REGBYTES(\x) - csrw CSR_MCAUSE, t0 - LOAD t0, 34 * REGBYTES(\x) - csrw CSR_MSUBM, t0 - LOAD t0, 33 * REGBYTES(\x) - csrw CSR_MEPC, t0 - LOAD t0, 32 * REGBYTES(\x) - csrw CSR_MSTATUS, t0 -.endm - - -/** - * @brife 出栈浮点寄存器 - * @param x 目标sp寄存器 - */ -.macro popVFPREGFILE x - flw f0, 36 * REGBYTES(\x) - flw f1, 37 * REGBYTES(\x) - flw f2, 38 * REGBYTES(\x) - flw f3, 39 * REGBYTES(\x) - flw f4, 40 * REGBYTES(\x) - flw f5, 41 * REGBYTES(\x) - flw f6, 42 * REGBYTES(\x) - flw f7, 43 * REGBYTES(\x) - flw f8, 44 * REGBYTES(\x) - flw f9, 45 * REGBYTES(\x) - flw f10, 46 * REGBYTES(\x) - flw f11, 47 * REGBYTES(\x) - flw f12, 48 * REGBYTES(\x) - flw f13, 49 * REGBYTES(\x) - flw f14, 50 * REGBYTES(\x) - flw f15, 51 * REGBYTES(\x) - flw f16, 52 * REGBYTES(\x) - flw f17, 53 * REGBYTES(\x) - flw f18, 54 * REGBYTES(\x) - flw f19, 55 * REGBYTES(\x) - flw f20, 56 * REGBYTES(\x) - flw f21, 57 * REGBYTES(\x) - flw f22, 58 * REGBYTES(\x) - flw f23, 59 * REGBYTES(\x) - flw f24, 60 * REGBYTES(\x) - flw f25, 61 * REGBYTES(\x) - flw f26, 62 * REGBYTES(\x) - flw f27, 63 * REGBYTES(\x) - flw f28, 64 * REGBYTES(\x) - flw f29, 65 * REGBYTES(\x) - flw f30, 66 * REGBYTES(\x) - flw f31, 67 * REGBYTES(\x) -.endm - - -/** - * @brife 清理fpu状态寄存器 + * @brief 清理fpu状态寄存器 */ .macro CONFIG_FS_CLEAN - li t0, (0x1 << 13) - csrc mstatus,t0 + li t0, (0x1 << 13) //配置FS为clean状态 + csrc mstatus, t0 li t0, (0x1 << 14) - csrs mstatus,t0 + csrs mstatus, t0 .endm /* -------------------------------------------------------------------------------------------------------- */ /** - * @brife trap入口函数 + * @brief trap入口函数 */ - .global trap_entry - .align 6 + .section .text.trap + .align 6// In CLIC mode, the trap entry must be 64bytes aligned + .global trap_entry + .weak trap_entry trap_entry: - pushREGFILE sp - + pushREGFILE sp //trap这里就直接使用当前栈，方便对当前位置进行异常分析， + //同时不担心(任务栈/中断栈/主栈)溢出，因为程序进入这里便不会返回了 portSAVE_CONTEXT_EXCP sp csrr a0, mcause mv a1, sp jal ulSynchTrap - mv sp,a0 + mv sp, a0 portRESTORE_CONTEXT_EXCP sp popREGFILE sp mret + /* -------------------------------------------------------------------------------------------------------- */ /** * @brife trq入口函数 @@ -434,3 +719,12 @@ xPortStartScheduler: */ vPortEndScheduler: j vPortEndScheduler + + +/* Default Handler for Exceptions / Interrupts */ +.global default_intexc_handler +.weak default_intexc_handler +Undef_Handler: +default_intexc_handler: +1: + j 1b diff --git a/workspace/TS100/Core/BSP/Pine64/Vendor/Lib/intexc_gd32vf103.S b/workspace/TS100/Core/BSP/Pine64/Vendor/Lib/intexc_gd32vf103.S deleted file mode 100644 index e90ebaa2..00000000 --- a/workspace/TS100/Core/BSP/Pine64/Vendor/Lib/intexc_gd32vf103.S +++ /dev/null @@ -1,35 +0,0 @@ -/* - * Copyright (c) 2019 Nuclei Limited. All rights reserved. - * - * SPDX-License-Identifier: Apache-2.0 - * - * 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 - * - * 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. - */ -/****************************************************************************** - * \file intexc_gd32vf103.S - * \brief NMSIS Interrupt and Exception Handling Template File - * for Device gd32vf103 - * \version V1.00 - * \date 7 Jan 2020 - * - ******************************************************************************/ - -#include "riscv_encoding.h" - -/* Default Handler for Exceptions / Interrupts */ -.global default_intexc_handler -.weak default_intexc_handler -Undef_Handler: -default_intexc_handler: -1: - j 1b diff --git a/workspace/TS100/Core/BSP/Pine64/Vendor/RISCV/entry.S b/workspace/TS100/Core/BSP/Pine64/Vendor/RISCV/entry.S deleted file mode 100644 index 67987d26..00000000 --- a/workspace/TS100/Core/BSP/Pine64/Vendor/RISCV/entry.S +++ /dev/null @@ -1,291 +0,0 @@ -#include "riscv_encoding.h" -#include "riscv_bits.h" -#include "n200_eclic.h" -#include "n200_timer.h" - -#define USE_MSP 1 //启用中断栈 - - -/** - * @brief 压栈通用寄存器 - * @param x 目标sp寄存器 - */ -.macro pushREGFILE x -#ifdef __riscv_flen - addi \x, \x, -REGBYTES * 68 //36+32 -#else - addi \x, \x, -REGBYTES * 36 -#endif - STORE x1, 1 * REGBYTES(\x) - STORE x2, 2 * REGBYTES(\x) - #STORE x3, 3 * REGBYTES(\x) - #STORE x4, 4 * REGBYTES(\x) - STORE x5, 5 * REGBYTES(\x) - STORE x6, 6 * REGBYTES(\x) - STORE x7, 7 * REGBYTES(\x) - STORE x8, 8 * REGBYTES(\x) - STORE x9, 9 * REGBYTES(\x) - STORE x10, 10 * REGBYTES(\x) - STORE x11, 11 * REGBYTES(\x) - STORE x12, 12 * REGBYTES(\x) - STORE x13, 13 * REGBYTES(\x) - STORE x14, 14 * REGBYTES(\x) - STORE x15, 15 * REGBYTES(\x) -#ifndef __riscv_32e - STORE x16, 16 * REGBYTES(\x) - STORE x17, 17 * REGBYTES(\x) - STORE x18, 18 * REGBYTES(\x) - STORE x19, 19 * REGBYTES(\x) - STORE x20, 20 * REGBYTES(\x) - STORE x21, 21 * REGBYTES(\x) - STORE x22, 22 * REGBYTES(\x) - STORE x23, 23 * REGBYTES(\x) - STORE x24, 24 * REGBYTES(\x) - STORE x25, 25 * REGBYTES(\x) - STORE x26, 26 * REGBYTES(\x) - STORE x27, 27 * REGBYTES(\x) - STORE x28, 28 * REGBYTES(\x) - STORE x29, 29 * REGBYTES(\x) - STORE x30, 30 * REGBYTES(\x) - STORE x31, 31 * REGBYTES(\x) -#endif -.endm - - -/** - * @brief 压栈csr寄存器（CSR_MSTATUS、CSR_MEPC、CSR_MSUBM、CSR_MCAUSE） - * @param x 目标sp寄存器 - */ -.macro portSAVE_CONTEXT_EXCP x - csrr t0, CSR_MSTATUS - STORE t0, 32 * REGBYTES(\x) - csrr t0, CSR_MEPC - STORE t0, 33 * REGBYTES(\x) - csrr t0, CSR_MSUBM - STORE t0, 34 * REGBYTES(\x) - csrr t0, CSR_MCAUSE - STORE t0, 35 * REGBYTES(\x) -.endm - - -/** - * @brief 压栈浮点寄存器 - * @param x 目标sp寄存器 - */ -.macro popVFPREGFILE x - flw f0, 36 * REGBYTES(\x) - flw f1, 37 * REGBYTES(\x) - flw f2, 38 * REGBYTES(\x) - flw f3, 39 * REGBYTES(\x) - flw f4, 40 * REGBYTES(\x) - flw f5, 41 * REGBYTES(\x) - flw f6, 42 * REGBYTES(\x) - flw f7, 43 * REGBYTES(\x) - flw f8, 44 * REGBYTES(\x) - flw f9, 45 * REGBYTES(\x) - flw f10,46 * REGBYTES(\x) - flw f11, 47 * REGBYTES(\x) - flw f12, 48 * REGBYTES(\x) - flw f13, 49 * REGBYTES(\x) - flw f14, 50 * REGBYTES(\x) - flw f15, 51 * REGBYTES(\x) - flw f16, 52 * REGBYTES(\x) - flw f17, 53 * REGBYTES(\x) - flw f18, 54 * REGBYTES(\x) - flw f19, 55 * REGBYTES(\x) - flw f20, 56 * REGBYTES(\x) - flw f21, 57 * REGBYTES(\x) - flw f22, 58 * REGBYTES(\x) - flw f23, 59 * REGBYTES(\x) - flw f24, 60 * REGBYTES(\x) - flw f25, 61 * REGBYTES(\x) - flw f26, 62 * REGBYTES(\x) - flw f27, 63 * REGBYTES(\x) - flw f28, 64 * REGBYTES(\x) - flw f29, 65 * REGBYTES(\x) - flw f30, 66 * REGBYTES(\x) - flw f31, 67 * REGBYTES(\x) -.endm - - -/** - * @brief 出栈通用寄存器 - * @param x 目标sp寄存器 - */ -.macro popREGFILE x - LOAD x1, 1 * REGBYTES(\x) - #LOAD x2, 2 * REGBYTES(\x) - #LOAD x3, 3 * REGBYTES(\x) - #LOAD x4, 4 * REGBYTES(\x) - LOAD x5, 5 * REGBYTES(\x) - LOAD x6, 6 * REGBYTES(\x) - LOAD x7, 7 * REGBYTES(\x) - LOAD x8, 8 * REGBYTES(\x) - LOAD x9, 9 * REGBYTES(\x) - LOAD x10, 10 * REGBYTES(\x) - LOAD x11, 11 * REGBYTES(\x) - LOAD x12, 12 * REGBYTES(\x) - LOAD x13, 13 * REGBYTES(\x) - LOAD x14, 14 * REGBYTES(\x) - LOAD x15, 15 * REGBYTES(\x) -#ifndef __riscv_32e - LOAD x16, 16 * REGBYTES(\x) - LOAD x17, 17 * REGBYTES(\x) - LOAD x18, 18 * REGBYTES(\x) - LOAD x19, 19 * REGBYTES(\x) - LOAD x20, 20 * REGBYTES(\x) - LOAD x21, 21 * REGBYTES(\x) - LOAD x22, 22 * REGBYTES(\x) - LOAD x23, 23 * REGBYTES(\x) - LOAD x24, 24 * REGBYTES(\x) - LOAD x25, 25 * REGBYTES(\x) - LOAD x26, 26 * REGBYTES(\x) - LOAD x27, 27 * REGBYTES(\x) - LOAD x28, 28 * REGBYTES(\x) - LOAD x29, 29 * REGBYTES(\x) - LOAD x30, 30 * REGBYTES(\x) - LOAD x31, 31 * REGBYTES(\x) -#endif -#ifdef __riscv_flen - addi \x, \x, REGBYTES * 68 //36+32 -#else - addi \x, \x, REGBYTES * 36 -#endif -.endm - - -/** - * @brief 出栈csr寄存器（CSR_MSTATUS、CSR_MEPC、CSR_MSUBM、CSR_MCAUSE） - * @param x 目标sp寄存器 - */ -.macro portRESTORE_CONTEXT_EXCP x - LOAD t0, 35*REGBYTES(\x) - csrw CSR_MCAUSE, t0 - LOAD t0, 34*REGBYTES(\x) - csrw CSR_MSUBM, t0 - LOAD t0, 33*REGBYTES(\x) - csrw CSR_MEPC, t0 - LOAD t0, 32*REGBYTES(\x) - csrw CSR_MSTATUS, t0 -.endm - - -/** - * @brief 出栈浮点寄存器 - * @param x 目标sp寄存器 - */ -.macro pushVFPREGFILE x - fsw f0, 36 * REGBYTES(\x) - fsw f1, 37 * REGBYTES(\x) - fsw f2, 38 * REGBYTES(\x) - fsw f3, 39 * REGBYTES(\x) - fsw f4, 40 * REGBYTES(\x) - fsw f5, 41 * REGBYTES(\x) - fsw f6, 42 * REGBYTES(\x) - fsw f7, 43 * REGBYTES(\x) - fsw f8, 44 * REGBYTES(\x) - fsw f9, 45 * REGBYTES(\x) - fsw f10, 46 * REGBYTES(\x) - fsw f11, 47 * REGBYTES(\x) - fsw f12, 48 * REGBYTES(\x) - fsw f13, 49 * REGBYTES(\x) - fsw f14, 50 * REGBYTES(\x) - fsw f15, 51 * REGBYTES(\x) - fsw f16, 52 * REGBYTES(\x) - fsw f17, 53 * REGBYTES(\x) - fsw f18, 54 * REGBYTES(\x) - fsw f19, 55 * REGBYTES(\x) - fsw f20, 56 * REGBYTES(\x) - fsw f21, 57 * REGBYTES(\x) - fsw f22, 58 * REGBYTES(\x) - fsw f23, 59 * REGBYTES(\x) - fsw f24, 60 * REGBYTES(\x) - fsw f25, 61 * REGBYTES(\x) - fsw f26, 62 * REGBYTES(\x) - fsw f27, 63 * REGBYTES(\x) - fsw f28, 64 * REGBYTES(\x) - fsw f29, 65 * REGBYTES(\x) - fsw f30, 66 * REGBYTES(\x) - fsw f31, 67 * REGBYTES(\x) -.endm - - -/** - * @brief 清理fpu状态寄存器 - */ -.macro CONFIG_FS_CLEAN - li t0, (0x1 << 13) //配置FS为clean状态 - csrc mstatus, t0 - li t0, (0x1 << 14) - csrs mstatus, t0 -.endm - - -/* -------------------------------------------------------------------------------------------------------- */ -/** - * @brief trap入口函数 - */ - .section .text.trap - .align 6// In CLIC mode, the trap entry must be 64bytes aligned - .global trap_entry - .weak trap_entry -trap_entry: - pushREGFILE sp //trap这里就直接使用当前栈，方便对当前位置进行异常分析， - //同时不担心(任务栈/中断栈/主栈)溢出，因为程序进入这里便不会返回了 - portSAVE_CONTEXT_EXCP sp - - csrr a0, mcause - mv a1, sp - jal ulSynchTrap - mv sp, a0 - - portRESTORE_CONTEXT_EXCP sp - popREGFILE sp - mret - - -/* -------------------------------------------------------------------------------------------------------- */ -/** - * @brief irq入口函数 - */ - .section .text.irq - .align 2 - .global irq_entry - .weak irq_entry -irq_entry: -#if USE_MSP - csrrw sp, CSR_MSCRATCHCSWL, sp -#endif - pushREGFILE sp //保存通用寄存器 - portSAVE_CONTEXT_EXCP sp -#ifdef __riscv_flen - csrr t2, mstatus - li t0, (0x3 << 13) - and t1, t2, t0 - bne t1, t0, 1f //浮点寄存器状态为Dirty状态，则保存浮点寄存器, 否则不用保存 - pushVFPREGFILE sp -1: - CONFIG_FS_CLEAN -#endif - - csrrw ra, CSR_JALMNXTI, ra //跳转到中断向量表入口地址，中断处理返回时继续回到此处 - - csrc CSR_MSTATUS, MSTATUS_MIE //此时中断处理完毕，中断关闭，注意mret退出中断时将恢复从mpie恢复mie， - //因此在中断内部修改mie仅会保持中断mret前，退出中断将恢复为进中断前状态 -#ifdef __riscv_flen - csrr t2, mstatus - li t0, (0x3 << 13) - and t1, t2, t0 - bne t1, t0, 2f //浮点寄存器状态为Dirty状态，则恢复浮点寄存器, 否则不用恢复 - popVFPREGFILE sp -2: -#endif - portRESTORE_CONTEXT_EXCP sp -#ifdef __riscv_flen - CONFIG_FS_CLEAN -#endif - popREGFILE sp -#if USE_MSP - csrrw sp, CSR_MSCRATCHCSWL, sp -#endif - mret diff --git a/workspace/TS100/Core/BSP/Pine64/Vendor/RISCV/start.S b/workspace/TS100/Core/BSP/Pine64/Vendor/RISCV/start.S deleted file mode 100644 index 0efa55b1..00000000 --- a/workspace/TS100/Core/BSP/Pine64/Vendor/RISCV/start.S +++ /dev/null @@ -1,289 +0,0 @@ -// See LICENSE for license details. - -#include "riscv_encoding.h" - - .section .init - - .weak eclic_msip_handler //弱定义函数，这些在编译为bin后可以看到将全部为0 - .weak eclic_mtip_handler - .weak eclic_bwei_handler - .weak eclic_pmovi_handler - .weak WWDGT_IRQHandler - .weak LVD_IRQHandler - .weak TAMPER_IRQHandler - .weak RTC_IRQHandler - .weak FMC_IRQHandler - .weak RCU_IRQHandler - .weak EXTI0_IRQHandler - .weak EXTI1_IRQHandler - .weak EXTI2_IRQHandler - .weak EXTI3_IRQHandler - .weak EXTI4_IRQHandler - .weak DMA0_Channel0_IRQHandler - .weak DMA0_Channel1_IRQHandler - .weak DMA0_Channel2_IRQHandler - .weak DMA0_Channel3_IRQHandler - .weak DMA0_Channel4_IRQHandler - .weak DMA0_Channel5_IRQHandler - .weak DMA0_Channel6_IRQHandler - .weak ADC0_1_IRQHandler - .weak CAN0_TX_IRQHandler - .weak CAN0_RX0_IRQHandler - .weak CAN0_RX1_IRQHandler - .weak CAN0_EWMC_IRQHandler - .weak EXTI5_9_IRQHandler - .weak TIMER0_BRK_IRQHandler - .weak TIMER0_UP_IRQHandler - .weak TIMER0_TRG_CMT_IRQHandler - .weak TIMER0_Channel_IRQHandler - .weak TIMER1_IRQHandler - .weak TIMER2_IRQHandler - .weak TIMER3_IRQHandler - .weak I2C0_EV_IRQHandler - .weak I2C0_ER_IRQHandler - .weak I2C1_EV_IRQHandler - .weak I2C1_ER_IRQHandler - .weak SPI0_IRQHandler - .weak SPI1_IRQHandler - .weak USART0_IRQHandler - .weak USART1_IRQHandler - .weak USART2_IRQHandler - .weak EXTI10_15_IRQHandler - .weak RTC_Alarm_IRQHandler - .weak USBFS_WKUP_IRQHandler - .weak EXMC_IRQHandler - .weak TIMER4_IRQHandler - .weak SPI2_IRQHandler - .weak UART3_IRQHandler - .weak UART4_IRQHandler - .weak TIMER5_IRQHandler - .weak TIMER6_IRQHandler - .weak DMA1_Channel0_IRQHandler - .weak DMA1_Channel1_IRQHandler - .weak DMA1_Channel2_IRQHandler - .weak DMA1_Channel3_IRQHandler - .weak DMA1_Channel4_IRQHandler - .weak CAN1_TX_IRQHandler - .weak CAN1_RX0_IRQHandler - .weak CAN1_RX1_IRQHandler - .weak CAN1_EWMC_IRQHandler - .weak USBFS_IRQHandler - -vector_base: //中断向量表 - j _start //第一条指令即跳转到_start处开始执行 - .align 2 - .word 0 - .word 0 - .word eclic_msip_handler - .word 0 - .word 0 - .word 0 - .word eclic_mtip_handler - .word 0 - .word 0 - .word 0 - .word 0 - .word 0 - .word 0 - .word 0 - .word 0 - .word 0 - .word eclic_bwei_handler - .word eclic_pmovi_handler - .word WWDGT_IRQHandler - .word LVD_IRQHandler - .word TAMPER_IRQHandler - .word RTC_IRQHandler - .word FMC_IRQHandler - .word RCU_IRQHandler - .word EXTI0_IRQHandler - .word EXTI1_IRQHandler - .word EXTI2_IRQHandler - .word EXTI3_IRQHandler - .word EXTI4_IRQHandler - .word DMA0_Channel0_IRQHandler - .word DMA0_Channel1_IRQHandler - .word DMA0_Channel2_IRQHandler - .word DMA0_Channel3_IRQHandler - .word DMA0_Channel4_IRQHandler - .word DMA0_Channel5_IRQHandler - .word DMA0_Channel6_IRQHandler - .word ADC0_1_IRQHandler - .word CAN0_TX_IRQHandler - .word CAN0_RX0_IRQHandler - .word CAN0_RX1_IRQHandler - .word CAN0_EWMC_IRQHandler - .word EXTI5_9_IRQHandler - .word TIMER0_BRK_IRQHandler - .word TIMER0_UP_IRQHandler - .word TIMER0_TRG_CMT_IRQHandler - .word TIMER0_Channel_IRQHandler - .word TIMER1_IRQHandler - .word TIMER2_IRQHandler - .word TIMER3_IRQHandler - .word I2C0_EV_IRQHandler - .word I2C0_ER_IRQHandler - .word I2C1_EV_IRQHandler - .word I2C1_ER_IRQHandler - .word SPI0_IRQHandler - .word SPI1_IRQHandler - .word USART0_IRQHandler - .word USART1_IRQHandler - .word USART2_IRQHandler - .word EXTI10_15_IRQHandler - .word RTC_Alarm_IRQHandler - .word USBFS_WKUP_IRQHandler - .word 0 - .word 0 - .word 0 - .word 0 - .word 0 - .word EXMC_IRQHandler - .word 0 - .word TIMER4_IRQHandler - .word SPI2_IRQHandler - .word UART3_IRQHandler - .word UART4_IRQHandler - .word TIMER5_IRQHandler - .word TIMER6_IRQHandler - .word DMA1_Channel0_IRQHandler - .word DMA1_Channel1_IRQHandler - .word DMA1_Channel2_IRQHandler - .word DMA1_Channel3_IRQHandler - .word DMA1_Channel4_IRQHandler - .word 0 - .word 0 - .word CAN1_TX_IRQHandler - .word CAN1_RX0_IRQHandler - .word CAN1_RX1_IRQHandler - .word CAN1_EWMC_IRQHandler - .word USBFS_IRQHandler - - .globl _start - .type _start,@function - -_start: - - csrc CSR_MSTATUS, MSTATUS_MIE //CSR_MSTATUS &= ~0x8 mstatus[3]:0屏蔽全部中断 1不屏蔽全部中断 （当然这里全部中断是除过不可屏蔽中断） - /* Jump to logical address first to ensure correct operation of RAM region */ - la a0, _start //a0 = _start - li a1, 1 //a1 = 1 - slli a1, a1, 29 //a1 = 0x20000000 raw起始地址 - bleu a1, a0, _start0800 //if( a1 <= a0 ) JUMP _start0800 - srli a1, a1, 2 //a1 = 0x08000000 flash起始地址 - bleu a1, a0, _start0800 //if( a1 <= a0 ) JUMP _start0800 - la a0, _start0800 //a0 = _start0800 - add a0, a0, a1 //a0 = a0+a1 - jr a0 //JUMP a0 - -_start0800: - - /* Set the the NMI base to share with mtvec by setting CSR_MMISC_CTL */ - li t0, 0x200 //t0 = 0x200 - csrs CSR_MMISC_CTL, t0 //mmisc_ctl |= 0x200 CSR_MMISC_CTL[9]：设置NMI的地址与mtvec相同且，mcause.EXCCODE = 0xfff - //cs开头的指令是特有的用来操作内核寄存器的的指令，内核寄存器是一组特有的12位地址 - - /* Intial the mtvt*/ - la t0, vector_base //t0 = vector_base 向量表地址 - csrw CSR_MTVT, t0 //mtvt = vector_base 中断向量表基地址 - - /* Intial the mtvt2 and enable it*/ - la t0, irq_entry //t0 = irq_entry irq_entry定义在entry.S,有freertos操作系统情况下定义在portasm.S - csrw CSR_MTVT2, t0 //mtvt2 = irq_entry mtvt2[31:2]: 中断入口函数地址 - csrs CSR_MTVT2, 0x1 //mtvt2 |= 0x1 mtvt2[0]: 1配置mtvt2的配置有效，配0则为mtvec内地址 - - /* Intial the CSR MTVEC for the Trap ane NMI base addr*/ - la t0, trap_entry //t0 = trap_entry trap_entry定义在entry.S,有freertos操作系统情况下定义在portasm.S - csrw CSR_MTVEC, t0 //mtvec = trap_entry mtvec[31:6]：异常入口地址 - // mtvec[5:0]：0B00011 -- ECLIC中断模式 其他：默认模式 - // 这里配置为默认模式 - // trap_entry基本上可以理解为arm里的hard/mem/use/svc等fault了， - // 这里在移植freertos时就使用了 ecall 进入trap_entry里 相当于arm里的PendSVC - - /* OS启动前配置中断栈为FHEAP的end地址 */ - la t0, ucHeap - csrw CSR_MSCRATCH, t0 - -#ifdef __riscv_flen //浮点宏 - /* Enable FPU */ - li t0, MSTATUS_FS //t0 = 0x6000 - csrs mstatus, t0 //mstatus |= 0x6000 mstatus[14:13]:非零值启用浮点单元，配置为1或2会在第一次使用浮点单元时变为3，这里直接配置为3 - csrw fcsr, x0 //fcsr = x0 = 0 ??这里x0是否指的是zero通用寄存器值? 这个寄存器0-4位是浮点异常状态标志，5-7位是浮点舍入模式配置 -#endif - -.option push -.option norelax - la gp, __global_pointer$ //__global_pointer$定义在link连接脚本内，指向所有.data段后偏移0x800的地址,0x800为2K，其值源于下文解释 - //gp 意为global pointer （全局指针）寄存器是一个解决方案， - //为了以进一步优化存储器访问单个4KB区域内。 - //链接器使用__global_pointer$符号定义来比较内存地址，如果在范围内， - //则它将绝对/相对pc寻址替换为gp相对寻址，从而使代码更有效。这个过程通过-Wl,--no-relax选项使用。 - //这里.option norelax起到-Wl,--no-relax作用，就不需要在编译选项添加了 - //上文参考自：https://gnu-mcu-eclipse.github.io/arch/riscv/programmer/#the-gp-global-pointer-register - //要让 relaxing 优化起作用，编译时要加入 -msmall-data-limit=n 参数，有了这个参数， - //编译器会把内存空间小于 n 字节的静态变量放入 .sdata 或者 .sdata.* 节， - //然后链接器将这部分静态变量集中在 __global_pointer$ +/- 2K 的范围内。 - //上文参考自：https://blog.csdn.net/zoomdy/article/details/100703451 -.option pop - la sp, _sp //sp = 主栈栈顶地址 _sp定义在link连接脚本内 - - /* Load data section */ - la a0, _data_lma //a0 = data的Load Memory Address _data_lma定义在link连接脚本内 - la a1, _data //a1 = data的Run Memory Address _data定义在link连接脚本内 - la a2, _edata //a2 = data的Run Memory Address结束地址 _edata定义在link连接脚本内 - bgeu a1, a2, 2f //if( a1 >= a2 ) JUMP 2f 原则上不会出现_data地址大于_edata地址 - //如果出现了则直接跳转到 2f 即下一个2标签 -1: - lw t0, (a0) //t0 = _data_lma - sw t0, (a1) //*_data = t0 即 *_data_lma，按word写入 - addi a0, a0, 4 //a0 = a0 + 4 下一个ward - addi a1, a1, 4 //a1 = a1 + 4 - bltu a1, a2, 1b //if( a1 < a2 ) JUMP 1b 如果未到达_edata则跳转到 1b 即上一个1标签，这里会完成一个循环 -2: - /* Clear bss section */ - la a0, __bss_start //a0 = __bss_start 初值为0的全局变量段起始地址 __bss_start定义在link连接脚本内 - la a1, _end //a1 = _end 初值为0的全局变量段结束地址 _end定义在link连接脚本内 - bgeu a0, a1, 2f //if( a0 >= a1 ) JUMP 2f 原则上不会出现__bss_start地址大于_end地址 - //如果出现了则直接跳转到 2f 即下一个2标签 -1: - sw zero, (a0) //*__bss_start = zero = 0 bss段清除为0 - addi a0, a0, 4 //a0 = a0 + 4 下一个ward - bltu a0, a1, 1b //if( a0 < a1 ) JUMP 1b 如果未到达_end则跳转到 1b 即上一个1标签，这里会完成一个循环 - - //程序执行到这里全局变量就以及处理完毕了 -2: - /*enable mcycle_minstret*/ - csrci CSR_MCOUNTINHIBIT, 0x5 //CSR_MCOUNTINHIBIT &= ~0x5 这里清零了第0bit和第1bit，使能了mcycle计数和minstret计数 - //csrci这条指令处理立即数5bit，列如0x5只是0B00101，高位不处理 - /* - * Call vendor defined SystemInit to - * initialize the micro-controller system - */ - call SystemInit - /* Call global constructors */ - la a0, __libc_fini_array //a0 = __libc_fini_array newlib中atexit函数的参数 - call atexit //调用newlib中的 void atexit(void (*func)(void)) 函数 - //功能为注册main函数结束后调用的函数，这里是__libc_fini_array - call __libc_init_array //调用newlib中的 void __libc_init_array (void) 函数 - //这里要注意__libc_init_array函数会调用_init的钩子函数，用来做c环境初始化前的一些硬件初始化 - //列如时钟的配置等，这里_init定义在init.c - - //程序执行到这里C/C++环境就初始化完成了，可以进入main函数入口了 - /* argc = argv = 0 */ - li a0, 0 //a0 = 0 main函数参数argc = 0 - li a1, 0 //a1 = 0 main函数参数argv = 0 - call main //调用 int main(int argc,char **argv) 函数 - tail exit //main返回后调用newlib的exit函数, tail指令应该是不会返回的调用函数了 - -1: - j 1b //1b 即上一次1标签，即跳转到自己，程序到这里就死循环了，原则不会运行到这里 - - .global disable_mcycle_minstret -disable_mcycle_minstret: - csrsi CSR_MCOUNTINHIBIT, 0x5 //关闭了mcycle计数和minstret计数 - ret - - .global enable_mcycle_minstret -enable_mcycle_minstret: - csrci CSR_MCOUNTINHIBIT, 0x5 //使能了mcycle计数和minstret计数 - ret