diff options
Diffstat (limited to 'pk/entry.S')
| -rw-r--r-- | pk/entry.S | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/pk/entry.S b/pk/entry.S new file mode 100644 index 0000000..6f0d1a0 --- /dev/null +++ b/pk/entry.S @@ -0,0 +1,150 @@ +#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) + + # when coming from kernel, continue below its stack + mfpcr $ra,ASM_CR(PCR_SR) + and $ra,$ra,SR_PS + add $x2, $sp, -320 + bnez $ra, 1f + la $x2,stack_top-320 + +1: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: |