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kernel: 0.902
debug: 0.848
graphic: 0.839
device: 0.680
performance: 0.679
boot: 0.672
architecture: 0.650
risc-v: 0.549
semantic: 0.448
x86: 0.416
peripherals: 0.375
user-level: 0.371
permissions: 0.314
PID: 0.280
ppc: 0.246
mistranslation: 0.233
register: 0.228
i386: 0.213
virtual: 0.210
vnc: 0.171
socket: 0.147
network: 0.129
hypervisor: 0.118
TCG: 0.113
VMM: 0.102
assembly: 0.101
KVM: 0.093
arm: 0.072
files: 0.063
riscv64 cannot use the mret instruction to jump to the address corresponding to s mode
Description of problem:
I use coreboot to boot my linux kernel.The kernel is copied at 0x82200000,I set reg mepc 0x82200000,and set reg mstatus a00000800.
and I use "mret" instruction so that qemu can jump to 0x82200000 and enter S mode.But some errors happened.
It shows:
[DEBUG] Exception: Instruction access fault
[DEBUG] Hart ID: 0
[DEBUG] Previous mode: machine
[DEBUG] Bad instruction pc: 0x8103f7c0
[DEBUG] Bad address: 0x00000000
[DEBUG] Stored ra: 0x8103f7b8
[DEBUG] Stored sp: 0x82032f08
Bad instruction pc: 0x8103f7c0 in my elf file instruction is "mret".
So I can not jump to my kernel's load address.
I think when I use -bios option,my qemu should in M mode.How could I can jump to my mepc address?
Steps to reproduce:
1.download qemu
2.download coreboot
Additional information:
When I enter qemu with -bios option,I find that the reg mstatus is 0xa0000000.
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