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#include "pcr.h"
#ifdef PK_ENABLE_KERNEL_64BIT
# define STORE sd
# define LOAD ld
# define REGBYTES 8
#else
# define STORE sw
# define LOAD lw
# define REGBYTES 4
#endif
.text
.set noat
.ent save_tf
save_tf: # write the trap frame onto the stack
# save gprs
STORE $x2,2*REGBYTES($x1)
mfpcr $x2,ASM_CR(PCR_K1)
STORE $x2,1*REGBYTES($x1) # $x1 is actually in $PCR_K1
STORE $x3,3*REGBYTES($x1)
STORE $x4,4*REGBYTES($x1)
STORE $x5,5*REGBYTES($x1)
STORE $x6,6*REGBYTES($x1)
STORE $x7,7*REGBYTES($x1)
STORE $x8,8*REGBYTES($x1)
STORE $x9,9*REGBYTES($x1)
STORE $x10,10*REGBYTES($x1)
STORE $x11,11*REGBYTES($x1)
STORE $x12,12*REGBYTES($x1)
STORE $x13,13*REGBYTES($x1)
STORE $x14,14*REGBYTES($x1)
STORE $x15,15*REGBYTES($x1)
STORE $x16,16*REGBYTES($x1)
STORE $x17,17*REGBYTES($x1)
STORE $x18,18*REGBYTES($x1)
STORE $x19,19*REGBYTES($x1)
STORE $x20,20*REGBYTES($x1)
STORE $x21,21*REGBYTES($x1)
STORE $x22,22*REGBYTES($x1)
STORE $x23,23*REGBYTES($x1)
STORE $x24,24*REGBYTES($x1)
STORE $x25,25*REGBYTES($x1)
STORE $x26,26*REGBYTES($x1)
STORE $x27,27*REGBYTES($x1)
STORE $x28,28*REGBYTES($x1)
STORE $x29,29*REGBYTES($x1)
STORE $x30,30*REGBYTES($x1)
mfpcr $x2,ASM_CR(PCR_K0)
STORE $x2,31*REGBYTES($x1) # $ra is actually in $PCR_K0
# get sr, epc, badvaddr, cr29 (tid)
mfpcr $x2,ASM_CR(PCR_SR) # sr
STORE $x2,32*REGBYTES($x1)
mfpcr $x2,ASM_CR(PCR_EPC) # epc
STORE $x2,33*REGBYTES($x1)
mfpcr $x2,ASM_CR(PCR_BADVADDR) # badvaddr
STORE $x2,34*REGBYTES($x1)
mfcr $x2,ASM_CR(29) # cr29 (tid)
STORE $x2,35*REGBYTES($x1)
jr $ra
.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)
# restore cr29 (tid)
LOAD $x2,35*REGBYTES($x1)
mtcr $x2,ASM_CR(29)
# 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
#define TIMER_IRQ_HANDLER \
.align 7; \
mtpcr $x2,ASM_CR(PCR_K0); \
mtpcr $x1,ASM_CR(PCR_K1); \
mfpcr $x1,ASM_CR(PCR_COMPARE); \
liw $x2,TIMER_PERIOD; \
addw $x1,$x1,$x2; \
mtpcr $x1,ASM_CR(PCR_COMPARE); \
mfpcr $x1,ASM_CR(PCR_K1); \
mfpcr $x2,ASM_CR(PCR_K0); \
eret
#define TRAP_TABLE_ENTRY(x) \
.align 7; \
mtpcr $ra,ASM_CR(PCR_K0); \
mtpcr $x1,ASM_CR(PCR_K1); \
law $x1,stack_top-320; \
jal save_tf; \
move $sp,$x1; \
move $a0,$x1; \
ei; \
jal x; \
unimp
.align 12
.global trap_table
.ent trap_table
trap_table:
TRAP_TABLE_ENTRY(handle_illegal_instruction)
TRAP_TABLE_ENTRY(handle_privileged_instruction)
TRAP_TABLE_ENTRY(handle_fp_disabled)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_misaligned_fetch)
TRAP_TABLE_ENTRY(handle_misaligned_ldst)
TRAP_TABLE_ENTRY(handle_fault_fetch)
TRAP_TABLE_ENTRY(handle_fault_ldst)
TRAP_TABLE_ENTRY(handle_syscall)
TRAP_TABLE_ENTRY(handle_breakpoint)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TRAP_TABLE_ENTRY(handle_badtrap)
TIMER_IRQ_HANDLER
.align 12
.end trap_table
.bss
.global stack_bot
.global stack_top
stack_bot:
.skip 4096
stack_top:
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