Csrw mepc t0
WebIs it me or qemu broke? Here is the toy code I test..section .text.init .global _start _start: .option push .option norelax la gp, _global_pointer .option pop la sp, _stack_start la t0, main csrw mepc, t0 li t1, 0b1 << 11 csrw mstatus, t1 li t2, 0 csrw satp, t2 la ra, wfi_spin csrw mtvec, ra mret wfi_spin: wfi j wfi_spin WebCSRW rs1, csr (funct3 = CSRRW, rd = x0): csr rs1 ... t0 to t6 – temporary registers (caller-saved) ... Passes mcause, mepc, stack pointer to the IH (a C function) to handle the specific interrupt 3. On the return from the IH, writes the return value to mepc 4.
Csrw mepc t0
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WebAug 14, 2024 · 芯片上电默认进入的是机器模式,通过将mstatus中的MPP值设置为00(00: User, 01: Supervisor, 11: Machine), 并将main函数的地址赋值给mepc,调用mret,使得用户在进入main函数运行时,芯片由机器模式切换为用户模式。 Webcsrr a1, mepc: mv a2, sp: jal handle_trap: csrw mepc, a0 # Remain in M-mode after eret: li t0, MSTATUS_MPP: csrs mstatus, t0: LREG x1, 1*REGBYTES(sp) LREG x2, 2*REGBYTES(sp) LREG x3, …
http://csg.csail.mit.edu/6.175/labs/lab8-riscv-exceptions.html Web将当前PC值保存到mepc寄存器; 在mcause寄存器中设置异常号; 从mtvec寄存器中取出异常入口地址; 跳转到异常入口地址; ecall和mret. ecall指令可以看成在函数调用前需要设置一些状态,比如mpc、mcause、mstatus,然后将然后就可以跳转到异常入口地址mtvec
WebNov 5, 2024 · This symbol comes from virt.lds la sp, _stack_end # Setting `mstatus` register: # 0b01 11: Machine's previous protection mode is 2 (MPP=2). li t0, 0b11 . 11 csrw … http://csg.csail.mit.edu/6.175/lectures/L09-RISC-V%20ISA.pdf
Webla t0, 1f // 将前面的标签1所在的PC地址赋值给t0. csrw mepc, t0 // 将t0的值赋值给CSR寄存器mepc. mret // 执行mret指令,则会将模式切换到User Mode,并且从前的标签1 ...
WebJan 23, 2024 · I think the function should instead set mepc to the correct return value with: csrw mepc, x1 and end with mret just like the function processed_source. This way, the MIE bit of mstatus gets set with the mret instruction. It could even jump to … ciclone freddy em tempo realWebcsrr a1, mepc: mv a2, sp: jal handle_trap: csrw mepc, a0 # Remain in M-mode after eret: li t0, MSTATUS_MPP: csrs mstatus, t0: LREG x1, 1*REGBYTES(sp) LREG x2, 2*REGBYTES(sp) LREG x3, … dguv information 202-093Webcsrw mtvec, t0; \ ###将-1赋值给t0,实际上是赋0xFFFF_FFFF给t0 ... 34129073 csrw mepc,t0 100d0: f1402573 csrr a0,mhartid 100d4: 30200073 mret 000100d8 : asm_start(): 100d8: aaaab5b7 lui a1,0xaaaab 100dc: aaa58593 addi a1,a1,-1366 # aaaaaaaa <_end+0xaaa98aaa> ... dguv information 203-006 bgi 608Webcsrw mstatus, t0: #ifdef STARTUP_ENABLE_HPE /* Enable PFIC HPE and nesting */ li t0, 0x3: #else /* Only enable nesting, not HPE */ li t0, 0x2: #endif: csrw 0x804, t0 /* Set vector table base address and mode (table entries contain absolute: address of ISR and interrupt entry is determined by IRQ number multiplied: by 4) */ la t0, _start: ori t0 ... ciclone englishWebApr 19, 2024 · li t0, 0x1f csrw 0xbc0, t0 /* Enable nested and hardware stack */ li t0, 0x1f csrw 0x804, ... 1 bnez a0, 1 b jal SystemInit la t0, main csrw mepc, t0 mret. 这里有一些自定义的 csr,比如 corecfgr(0xbc0),intsyscr(0x804,设置了 HWSTKEN=1, INESTEN=1, PMTCFG=0b11, HWSTKOVEN=1),具体参考 QingKeV4_Processor_Manual。接着代码 ... dguv information 203-005 pdfWebJul 9, 2024 · asm volatile ("addi t0, t0, 0x4"); asm volatile ("csrw mepc, t0");}} In the exception handler, we need to enable the timer interrupt by set the MTIE bit in the MIE … ciclon jeans blackWebExecute the mret instruction, after first setting up mstatus.mpp to S (01) and mepc to the address you want to start executing S mode from. To switch to U mode set mstatus.mpp … cic longwy bas