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// See LICENSE for license details.
#include "encoding.h"
#ifdef __riscv64
# define STORE sd
# define LOAD ld
# define REGBYTES 8
#else
# define STORE sw
# define LOAD lw
# define REGBYTES 4
#endif
.macro save_tf
# save gprs
STORE x3,3*REGBYTES(x2)
STORE x4,4*REGBYTES(x2)
STORE x5,5*REGBYTES(x2)
STORE x6,6*REGBYTES(x2)
STORE x7,7*REGBYTES(x2)
STORE x8,8*REGBYTES(x2)
STORE x9,9*REGBYTES(x2)
STORE x10,10*REGBYTES(x2)
STORE x11,11*REGBYTES(x2)
STORE x12,12*REGBYTES(x2)
STORE x13,13*REGBYTES(x2)
STORE x14,14*REGBYTES(x2)
STORE x15,15*REGBYTES(x2)
STORE x16,16*REGBYTES(x2)
STORE x17,17*REGBYTES(x2)
STORE x18,18*REGBYTES(x2)
STORE x19,19*REGBYTES(x2)
STORE x20,20*REGBYTES(x2)
STORE x21,21*REGBYTES(x2)
STORE x22,22*REGBYTES(x2)
STORE x23,23*REGBYTES(x2)
STORE x24,24*REGBYTES(x2)
STORE x25,25*REGBYTES(x2)
STORE x26,26*REGBYTES(x2)
STORE x27,27*REGBYTES(x2)
STORE x28,28*REGBYTES(x2)
STORE x29,29*REGBYTES(x2)
STORE x30,30*REGBYTES(x2)
STORE x31,31*REGBYTES(x2)
# get sr, epc, badvaddr, cause
csrr x3,sup0 # x1
csrr x4,sup1 # x2
csrr x5,status
csrr x6,epc
csrr x7,badvaddr
csrr x8,cause
STORE x3,1*REGBYTES(x2)
STORE x4,2*REGBYTES(x2)
STORE x5,32*REGBYTES(x2)
STORE x6,33*REGBYTES(x2)
STORE x7,34*REGBYTES(x2)
STORE x8,35*REGBYTES(x2)
la gp, _gp
# get faulting insn, if it wasn't a fetch-related trap
li x5,-1
STORE x5,36*REGBYTES(x2)
1:
.endm
.text
.globl pop_tf
pop_tf: # write the trap frame onto the stack
# restore gprs
LOAD a1,32*REGBYTES(a0)
LOAD a2,1*REGBYTES(a0)
LOAD a3,2*REGBYTES(a0)
csrw status, a1 # restore sr (disable interrupts)
csrw sup0, a2
csrw sup1, a3
move x1,a0
LOAD x3,3*REGBYTES(x1)
LOAD x4,4*REGBYTES(x1)
LOAD x5,5*REGBYTES(x1)
LOAD x6,6*REGBYTES(x1)
LOAD x7,7*REGBYTES(x1)
LOAD x8,8*REGBYTES(x1)
LOAD x9,9*REGBYTES(x1)
LOAD x10,10*REGBYTES(x1)
LOAD x11,11*REGBYTES(x1)
LOAD x12,12*REGBYTES(x1)
LOAD x13,13*REGBYTES(x1)
LOAD x14,14*REGBYTES(x1)
LOAD x15,15*REGBYTES(x1)
LOAD x16,16*REGBYTES(x1)
LOAD x17,17*REGBYTES(x1)
LOAD x18,18*REGBYTES(x1)
LOAD x19,19*REGBYTES(x1)
LOAD x20,20*REGBYTES(x1)
LOAD x21,21*REGBYTES(x1)
LOAD x22,22*REGBYTES(x1)
LOAD x23,23*REGBYTES(x1)
LOAD x24,24*REGBYTES(x1)
LOAD x25,25*REGBYTES(x1)
LOAD x26,26*REGBYTES(x1)
LOAD x27,27*REGBYTES(x1)
LOAD x28,28*REGBYTES(x1)
LOAD x29,29*REGBYTES(x1)
LOAD x30,30*REGBYTES(x1)
LOAD x31,31*REGBYTES(x1)
# gtfo!
LOAD x2,33*REGBYTES(x1)
csrr x1, sup0
csrw epc, x2
csrr x2, sup1
sret
.global trap_entry
trap_entry:
csrw sup0, x1
csrw sup1, x2
# when coming from kernel, continue below its stack
csrr x1, status
and x1, x1, SR_PS
add x2, sp, -320
bnez x1, 1f
la x2, stack_top-320
1:save_tf
move sp,x2
move a0,x2
j handle_trap
.bss
.align 4
.global stack_bot
.global stack_top
stack_bot:
.skip 4096
stack_top:
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