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#include "riscv_test.h"
#ifdef __riscv64
# define STORE sd
# define LOAD ld
# define REGBYTES 8
#else
# define STORE sw
# define LOAD lw
# define REGBYTES 4
#endif
#define STACK_TOP (_end + 131072)
.section ".text.init","ax",@progbits
reset_vector:
j handle_reset
/* NMI vector */
nmi_vector:
j wtf
trap_vector:
# we can safely clobber caller-saved registers here, because we were
# either invoked via do_tohost or we are about to bail out
csrr t0, mcause
li t1, CAUSE_SUPERVISOR_ECALL
beq t0, t1, handle_tohost
li t1, CAUSE_MACHINE_ECALL
beq t0, t1, handle_tohost
j wtf
handle_reset:
la sp, STACK_TOP - SIZEOF_TRAPFRAME_T
csrw mscratch, sp
li a1, 1337
la a0, userstart
j vm_boot
.globl pop_tf
pop_tf:
LOAD t0,33*REGBYTES(a0)
csrw sepc,t0
LOAD x1,1*REGBYTES(a0)
LOAD x2,2*REGBYTES(a0)
LOAD x3,3*REGBYTES(a0)
LOAD x4,4*REGBYTES(a0)
LOAD x5,5*REGBYTES(a0)
LOAD x6,6*REGBYTES(a0)
LOAD x7,7*REGBYTES(a0)
LOAD x8,8*REGBYTES(a0)
LOAD x9,9*REGBYTES(a0)
LOAD x11,11*REGBYTES(a0)
LOAD x12,12*REGBYTES(a0)
LOAD x13,13*REGBYTES(a0)
LOAD x14,14*REGBYTES(a0)
LOAD x15,15*REGBYTES(a0)
LOAD x16,16*REGBYTES(a0)
LOAD x17,17*REGBYTES(a0)
LOAD x18,18*REGBYTES(a0)
LOAD x19,19*REGBYTES(a0)
LOAD x20,20*REGBYTES(a0)
LOAD x21,21*REGBYTES(a0)
LOAD x22,22*REGBYTES(a0)
LOAD x23,23*REGBYTES(a0)
LOAD x24,24*REGBYTES(a0)
LOAD x25,25*REGBYTES(a0)
LOAD x26,26*REGBYTES(a0)
LOAD x27,27*REGBYTES(a0)
LOAD x28,28*REGBYTES(a0)
LOAD x29,29*REGBYTES(a0)
LOAD x30,30*REGBYTES(a0)
LOAD x31,31*REGBYTES(a0)
LOAD a0,10*REGBYTES(a0)
eret
.global trap_entry
trap_entry:
csrrw sp, sscratch, sp
# save gprs
STORE x1,1*REGBYTES(sp)
STORE x3,3*REGBYTES(sp)
STORE x4,4*REGBYTES(sp)
STORE x5,5*REGBYTES(sp)
STORE x6,6*REGBYTES(sp)
STORE x7,7*REGBYTES(sp)
STORE x8,8*REGBYTES(sp)
STORE x9,9*REGBYTES(sp)
STORE x10,10*REGBYTES(sp)
STORE x11,11*REGBYTES(sp)
STORE x12,12*REGBYTES(sp)
STORE x13,13*REGBYTES(sp)
STORE x14,14*REGBYTES(sp)
STORE x15,15*REGBYTES(sp)
STORE x16,16*REGBYTES(sp)
STORE x17,17*REGBYTES(sp)
STORE x18,18*REGBYTES(sp)
STORE x19,19*REGBYTES(sp)
STORE x20,20*REGBYTES(sp)
STORE x21,21*REGBYTES(sp)
STORE x22,22*REGBYTES(sp)
STORE x23,23*REGBYTES(sp)
STORE x24,24*REGBYTES(sp)
STORE x25,25*REGBYTES(sp)
STORE x26,26*REGBYTES(sp)
STORE x27,27*REGBYTES(sp)
STORE x28,28*REGBYTES(sp)
STORE x29,29*REGBYTES(sp)
STORE x30,30*REGBYTES(sp)
STORE x31,31*REGBYTES(sp)
csrrw t0,sscratch,sp
STORE t0,2*REGBYTES(sp)
# get sr, epc, badvaddr, cause
csrr t0,sstatus
STORE t0,32*REGBYTES(sp)
csrr t0,sepc
STORE t0,33*REGBYTES(sp)
csrr t0,sbadaddr
STORE t0,34*REGBYTES(sp)
csrr t0,scause
STORE t0,35*REGBYTES(sp)
move a0, sp
j handle_trap
.global do_tohost
do_tohost:
ecall
ret
handle_tohost:
1:csrrw t0, mtohost, a0
bnez t0, 1b
1:csrrw t0, mfromhost, x0
bnez t0, 1b
csrr t0, mepc
addi t0, t0, 4
csrw mepc, t0
eret
wtf:
li a0, 841
1:csrw mtohost, a0
j 1b
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