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.option norvc
.global _entry
.global fromhost
.global tohost
.text
_entry:
la t0, exception_handler
csrw mtvec, t0
csrr t1, mstatus
# Setting bit number 9 (mstatus.VS)
li t2, 1
slli t2, t2, 9
or t1, t1, t2
# Setting bit number 13 (mstatus.FS)
li t3, 1
slli t3, t3, 13
or t1, t1, t3
csrw mstatus, t1
la t0, SNIPPY_ENTRY
jalr t0
exception_handler:
csrr x10, mcause
# In case of breakpoint (Interrupt = 0, Exception code = 3) we finalize.
# Otherwise it's not the expected behavior and we go into an infinite loop.
li x11, 3
beq x10, x11, exit
j infinite_loop
exit:
li ra, 1
la sp, tohost
sd ra, 0(sp)
infinite_loop:
j infinite_loop
.balign 64
tohost:
.8byte 0x0
.balign 64
fromhost:
.8byte 0x0
|
