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handle basic exceptions in kernel

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This commit is contained in:
Connor Olding 2018-08-21 04:37:48 +02:00
parent 7ceff73194
commit 49780dbed7
1 changed files with 35 additions and 22 deletions
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57
kernel.asm
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@ -17,8 +17,8 @@ Start:
sd t4, 8(t0)
cache 0x19, 0(t0) // tell data cache to write itself out
cache 0x10, 0(t0) // tell instruction cache it needs to reload
// an instruction cache line is 2 rows, and a data cache line is 1 row, so
// i'm hoping just poking at the start of each row is enough to flush them.
// an instruction cache line is 2 rows, and a data cache line is 1 row,
// so poking at the start of each row is enough to flush them both.
bne t1, t2,-
addiu t0, t0, 0x10
@ -35,9 +35,7 @@ Start:
// enable even more interrupts.
lui t2, MI_BASE
ori t2, t2, MI_INTR_MASK
// lli t0, MI_INTR_MASK_ALL
// i don't have code to handle all the interrupts. in the meantime...
lli t0, MI_INTR_MASK_SP
lli t0, MI_INTR_MASK_ALL
sw t0, 0(t2)
// set BSD DOM1 stuff, whatever that is.
@ -334,7 +332,7 @@ if K_DEBUG {
KMaybeDumpString(KSNewline)
KMaybeDumpString(KSStates)
ori a0, k0, K_DUMP + 0x80 * 4
ori a0, k0, K_REASON
lli a1, 0x80
ori a2, k0, K_XXD
jal DumpAndWrite
@ -424,17 +422,13 @@ ReturnFromInterrupt:
eret
// no branch delay for eret
include "debug.asm"
KCode0:
KMaybeDumpString(KSCode0)
lui a0, MI_BASE
lw t0, MI_INTR(a0)
lw t1, MI_INTR_MASK(a0)
and s0, t0, t1 // if we don't care about an interrupt, get rid of it
KMILoop:
lui a0, MI_BASE
lw s0, MI_INTR(a0)
beqz s0,+
andi t3, s0, MI_INTR_SP // delay slot
@ -457,9 +451,6 @@ KMILoop:
nop
+
// can't do this apparently:
// lui a0, MI_BASE
// sw s0, MI_INTR(a0)
j KCodeDone
nop
@ -467,40 +458,60 @@ KMILoop:
KMISP:
KMaybeDumpString(KSMISP)
lli t0, CLR_SG3 | CLR_INT // delay slot
lui a1, SP_BASE
lw t1, SP_STATUS(a1)
andi t2, t1, RSP_BRK
beqz t2,+
li t0, CLR_SG3 | CLR_INT // delay slot
sw t0, SP_STATUS(a1)
+
// then check andi t1, SG1 | SG2 ?
j KMILoop
andi s0, ~MI_INTR_SP
KMISI:
KMaybeDumpString(KSMISI)
lui a1, SI_BASE
sw r0, SI_STATUS(a1)
j KMILoop
andi s0, ~MI_INTR_SI
KMIAI:
KMaybeDumpString(KSMIAI)
lli t0, 0x01
lui a1, AI_BASE
sw t0, AI_STATUS(a1)
j KMILoop
andi s0, ~MI_INTR_AI
KMIVI:
KMaybeDumpString(KSMIVI)
lui a1, VI_BASE
sw r0, VI_V_CURRENT_LINE(a1)
j KMILoop
andi s0, ~MI_INTR_VI
KMIPI:
KMaybeDumpString(KSMIPI)
lli t0, 0x02
lui a1, PI_BASE
sw t0, PI_STATUS(a1)
j KMILoop
andi s0, ~MI_INTR_PI
KMIDP:
KMaybeDumpString(KSMIDP)
lli t0, 0x800
lui a1, MI_BASE
sw t0, MI_INIT_MODE(a1)
j KMILoop
andi s0, ~MI_INTR_DP
@ -546,6 +557,8 @@ dw KCode20, KCode21, KCode22, KCode23
dw KCode24, KCode25, KCode26, KCode27
dw KCode28, KCode29, KCode30, KCode31
include "debug.asm"
if K_DEBUG {
KS(KSNewline, 10)
KSL(KSConsoleConfirmed, "USB debug console detected")