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#include "pcr.h"
#ifdef __riscv64
# define STORE sd
# define LOAD ld
# define REGBYTES 8
#else
# define STORE sw
# define LOAD lw
# define REGBYTES 4
#endif
.text
.ent save_tf
save_tf: # write the trap frame onto the stack
# 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)
mfpcr $x3,ASM_CR(PCR_K0)
STORE $x3,1*REGBYTES($x2) # $x1 is in $PCR_K0
mfpcr $x3,ASM_CR(PCR_K1)
STORE $x3,2*REGBYTES($x2) # $x2 is in $PCR_K1
# get sr, epc, badvaddr, cause
mfpcr $x3,ASM_CR(PCR_SR) # sr
STORE $x3,32*REGBYTES($x2)
mfpcr $x4,ASM_CR(PCR_EPC) # epc
STORE $x4,33*REGBYTES($x2)
mfpcr $x3,ASM_CR(PCR_BADVADDR) # badvaddr
STORE $x3,34*REGBYTES($x2)
mfpcr $x3,ASM_CR(PCR_CAUSE) # cause
STORE $x3,35*REGBYTES($x2)
# get faulting insn, if it wasn't a fetch-related trap
li $x5, CAUSE_MISALIGNED_FETCH
li $x6, CAUSE_FAULT_FETCH
beq $x3, $x5, 1f
beq $x3, $x6, 1f
lh $x3,0($x4)
lh $x4,2($x4)
sh $x3, 36*REGBYTES($x2)
sh $x4,2+36*REGBYTES($x2)
1:
ret
.end save_tf
.globl pop_tf
.ent pop_tf
pop_tf: # write the trap frame onto the stack
# restore gprs
LOAD $t0,32*REGBYTES($a0) # restore sr (should disable interrupts)
mtpcr $t0,ASM_CR(PCR_SR)
LOAD $x1,1*REGBYTES($a0)
mtpcr $x1,ASM_CR(PCR_K0)
LOAD $x1,2*REGBYTES($a0)
mtpcr $x1,ASM_CR(PCR_K1)
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)
mtpcr $x2,ASM_CR(PCR_EPC)
mfpcr $x1,ASM_CR(PCR_K0)
mfpcr $x2,ASM_CR(PCR_K1)
eret
.end pop_tf
.global trap_entry
.ent trap_entry
trap_entry:
mtpcr $ra,ASM_CR(PCR_K0)
mtpcr $x2,ASM_CR(PCR_K1)
la $x2,stack_top-320
jal save_tf
move $sp,$x2
move $a0,$x2
jal handle_trap
.end trap_entry
.bss
.global stack_bot
.global stack_top
stack_bot:
.skip 4096
stack_top:
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