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Receiving an interrupt no longer crashes, does seem to cause a general protection fault though (infinite loop time!).

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This commit is contained in:
neviyn 2018-04-28 01:06:02 +01:00
parent 347a5cbff3
commit 04768924e8
1 changed files with 87 additions and 72 deletions
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81
kernel/arch/i386/interrupts.nim
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@ -18,42 +18,39 @@ type
int_no, err_code: uint32 # Interrupt number and error code (if applicable)
eip, cs, eflags, useresp, ss: uint32 # Pushed by the processor automatically.
var
idt: IDT
idtAddr: uint32 = cast[uint32](idt.addr)
const
idtAddress: uint32 = 0x00000000
idt = cast[ptr IDT](idtAddress)
{.push stackTrace:off.}
proc idtFlush(){.inline,asmNoStackFrame.} =
asm """
lidt [`idtAddr`]
lidtl (0x0)
ret
"""
{.pop.}
proc isrHandler(registers: Registers){.exportc.} =
serial.write("Recieved interrupt:")
proc isrHandler(registers: Registers){.exportc, codegenDecl: "__attribute__((interrupt)) $# $#$#".} =
serial.write("Recieved interrupt handler:")
serial.write(registers.int_no)
serial.write("\L")
proc isrCommon() =
proc isrCommon(){.asmNoStackFrame,exportc.} =
asm """
pusha
movw %ax, %ds
mov %ds, %ax
push %eax
movw $0x10, %ax
movw %ds, %ax
movw %es, %ax
movw %fs, %ax
movw %gs, %ax
mov $0x10, %ax
mov %ax, %ds
mov %ax, %es
mov %ax, %fs
mov %ax, %gs
call `isrHandler`
pop %eax
movw %ds, %ax
movw %es, %ax
movw %fs, %ax
movw %gs, %ax
mov %ax, %ds
mov %ax, %es
mov %ax, %fs
mov %ax, %gs
popa
add $8, %esp
sti
iret
"""
@ -66,12 +63,35 @@ macro generateISR(code: static[uint8], isError: static[bool]): typed =
nnkFormalParams.newTree(
newEmptyNode()
),
newEmptyNode(),
nnkPragma.newTree(
newIdentNode("exportc")
),
newEmptyNode(),
nnkStmtList.newTree(
nnkAsmStmt.newTree(
newEmptyNode(),
newLit("cli\x0A" & (if isError: "" else: "push 0\x0A") & "push " & $code & "\x0A")
newLit((if isError: "" else: "push 0\x0A") & "push " & $code & "\x0A")
),
nnkCall.newTree(
nnkDotExpr.newTree(
newIdentNode("serial"),
newIdentNode("write")
),
newLit("Recieved interrupt:")
),
nnkCall.newTree(
nnkDotExpr.newTree(
newIdentNode("serial"),
newIdentNode("write")
),
newLit(code)
),
nnkCall.newTree(
nnkDotExpr.newTree(
newIdentNode("serial"),
newIdentNode("write")
),
newLit("\x0A")
),
nnkCall.newTree(
newIdentNode("isrCommon")
@ -84,17 +104,9 @@ proc idtSetGate(num: uint8, base: uint32, sel: uint16, flags: uint8) =
idt.entries[num].base_low = uint16(base and 0xFFFF)
idt.entries[num].base_high = uint16((base shr 16) and 0xFFFF)
idt.entries[num].zero = 0
idt.entries[num].flags = flags
idt.entries[num].flags = flags or 0x60
idt.entries[num].kernel_selector = sel
# Would like to generate these in a loop, but apparently
# Error: type mismatch: got <uint8, bool>
# but expected one of:
# macro generateISR(code: static[uint8]; isError: static[bool]): typed
# first type mismatch at position: 1
# required type: static[uint8]
# but expression 'uint8(i)' is of type: uint8
static:
generateISR(0, false)
generateISR(1, false)
@ -129,13 +141,15 @@ static:
generateISR(30, false)
generateISR(31, false)
let
const
selector: uint16 = 0x08
flags: uint8 = 0x8E
proc idtInstall*() =
idt.descriptor.limit = uint16(sizeof(IDTEntry) * idt.entries.len) - 1
idt.descriptor.limit = uint16(sizeof(idt.entries)) - 1
idt.descriptor.base = cast[uint32](idt.entries.addr)
for i in 0..idt.entries.len: # Zero IDT memory space
idtSetGate(uint8(i),0,0,0)
idtSetGate(0, cast[uint32](isr0), selector, flags)
idtSetGate(1, cast[uint32](isr1), selector, flags)
idtSetGate(2, cast[uint32](isr2), selector, flags)
@ -168,4 +182,5 @@ proc idtInstall*() =
idtSetGate(29, cast[uint32](isr29), selector, flags)
idtSetGate(30, cast[uint32](isr30), selector, flags)
idtSetGate(31, cast[uint32](isr31), selector, flags)
serial.write("Flushing IDT.\L")
idtFlush()