http://csg.csail.mit.edu/6.175/labs/lab8-riscv-exceptions.html Web#define CSR_MTVEC 0x305 #define CSR_MSCRATCH 0x340 ... + csrw sscratch, 0 + +#ifdef CONFIG_FPU + csrr t0, CSR_MISA + andi t0, t0, (COMPAT_HWCAP_ISA_F COMPAT_HWCAP_ISA_D) + bnez t0, .Lreset_regs_done + + li t1, SR_FS + csrs CSR_XSTATUS, t1 + fmv.s.x f0, zero
[12/15] riscv: clear the instruction cache and all registers when ...
WebDec 27, 2024 · The address of supervisor is now in t0, and we can see that the next instruction will use the csrw pseudoinstruction to write the address to mepc, the Machine Exception Program Counter. This CSR is used to instruct the processor where execution should continue when returning from a trap in M mode (using the mret instruction we saw … WebOn Thu, Dec 19, 2024 at 12:15 PM Greentime Hu wrote: > > This patch fixes that the sscratch register clearing in M-mode. It cleared > sscratch register in M-mode, but it should clear mscratch register. That will > cause kernel trap if the CPU core doesn't support S-mode when trying to access > sscratch. > Fixes: 9e80635619b5 … fob in full
(SBI) Supervisor Binary Interface – Stephen Marz
WebI am trying to write a reuseable macro to configure some CSR's in assembly. E.g.macro initTrap entry, status, enable la t0, entry csrw mtvec, t0 csrwi mstatus, status csrwi mie, enable .endm Then to use it (at least to test): initTrap trap_entry, 0x0, 0x0 Webcsrw mstatus, t0: la t0, .lower_to_smode: csrw mepc, t0: mret /* we should never get here, but if we do, hang */ j hang: #endif.lower_to_smode: /* mhartid is in a0. Park non-init cores */ bnez a0, hang /* SATP should be zero (like CR3 in x86), but let's make sure */ csrw satp, zero /* Zero BSS */ la t0, __bss_start: la t1, __bss_end: bgeu t0 ... WebLKML Archive on lore.kernel.org help / color / mirror / Atom feed * RISC-V nommu support v5 @ 2024-10-17 17:37 Christoph Hellwig 2024-10-17 17:37 ` [PATCH 01/15] riscv: cleanup Christoph Hellwig ` (15 more replies) 0 siblings, 16 replies; 49+ messages in thread From: Christoph Hellwig @ 2024-10-17 17:37 UTC (permalink / raw) To: Palmer … greer amps lightspeed into a tweed style amp