Use vectors for irq and nmi

sw/bios/devices/interrupt.s

@@ -6,12 +6,11 @@
 ;
 ; Checks for a BRK instruction and returns from all valid interrupts.
 
-.import   _handle_irq
-.import _cputc, _clrscr
-
 .export   _irq_int, _nmi_int
 
-.include "io.inc65"
+
+IRQ_VECTOR = $220
+NMI_VECTOR = $222
 
 .segment  "CODE"
 
@@ -20,81 +19,9 @@
 ; ---------------------------------------------------------------------------
 ; Non-maskable interrupt (NMI) service routine
 
-_nmi_int:  RTI                    ; Return from all NMI interrupts
+_nmi_int:  jmp (NMI_VECTOR)
 
 ; ---------------------------------------------------------------------------
 ; Maskable interrupt (IRQ) service routine
 
-_irq_int:  PHX                    ; Save X register contents to stack
-           TSX                    ; Transfer stack pointer to X
-           PHA                    ; Save accumulator contents to stack
-           INX                    ; Increment X so it points to the status
-           INX                    ;   register value saved on the stack
-           LDA $100,X             ; Load status register contents
-           AND #$10               ; Isolate B status bit
-           BNE break              ; If B = 1, BRK detected
-
-; ---------------------------------------------------------------------------
-; IRQ detected, return
-
-irq:       PLA                    ; Restore accumulator contents
-           PLX                    ; Restore X register contents
-           jsr _handle_irq        ; Handle the IRQ
-           RTI                    ; Return from all IRQ interrupts
-
-; ---------------------------------------------------------------------------
-; BRK detected, stop
-
-break:
-        pla
-        plx
-        jmp (bios_table,x)
-
-
-bios_table:
-        .addr   _console_clear
-        .addr   _console_read_char
-        .addr   _console_write_char
-
-
-_console_clear:
-        jsr _clrscr
-        rti
-
-_console_read_char:
-        ; not supported
-        rti
-
-_console_write_char:
-        jsr _cputc
-        rti
-
-
-
-; What functions do we need?
-; UART
-;   clear
-;   write character
-;   read character
-; DISK
-;   init (or should it just init on boot?)
-;   read sector into memory
-; FS
-;   init (if disk init succeeds, should it always try?)
-;   find add
-
-; I think that is all we need for now?
-; How do we call the functions?
-
-; we have to call `brk` to trigger the interrupt
-; in any of the three registers we can have arguments
-; or we could have them pushed to the stack, assuming
-; the stack is in the same location
-; Or you could pass a pointer which points to an array
-; of arguments
-
-; for things like clear, read/write character, and init you don't
-; need any arguments.
-
-; jump table index needs to be in x, but also needs to be a multiple
-; of 2.
+_irq_int:  jmp (IRQ_VECTOR)

sw/bios/irq.c

@@ -1,11 +0,0 @@
-
-#include <stdint.h>
-#include <conio.h>
-
-#include "devices/interrupt.h"
-#include "devices/uart.h"
-
-
-
-void handle_irq() {
-}

sw/kernel/devices/interrupt_controller.s

@@ -9,6 +9,8 @@
 .export _disable_irq
 .export _send_eoi
 
+.import irq_int, nmi_int
+
 IRQ_CMD_ADDR    = $effc
 IRQ_DAT_ADDR    = $effd
 
@@ -19,11 +21,24 @@ IRQ_CMD_ENABLE  = $20
 IRQ_CMD_TYPE    = $40
 IRQ_CMD_EOI     = $ff
 
+IRQ_VECTOR = $220
+NMI_VECTOR = $222
+
 .code
 
 ; void init_irq();
 ; mask all IRQs, set all type to edge.
 .proc _init_interrupt_controller
+    lda #<irq_int
+    sta IRQ_VECTOR
+    lda #>irq_int
+    sta IRQ_VECTOR+1
+
+    lda #<nmi_int
+    sta NMI_VECTOR
+    lda #>nmi_int
+    sta NMI_VECTOR+1
+
     ldx #$20    ; enable
     ldy #00
     jsr cmd_all

sw/kernel/interrupts/interrupt.h

@@ -6,9 +6,6 @@
 #define BUTTON  (1 << 0)
 #define UART    (1 << 1)
 
-void irq_int();
-void nmi_int();
-
 void register_irq(void* addr, uint8_t irqn);
 
 uint8_t irq_get_status();

sw/kernel/interrupts/interrupt.s

@@ -4,7 +4,7 @@
 
 .import _enable_irq
 
-.export   _irq_int, _nmi_int
+.export   irq_int, nmi_int
 .export _register_irq
 
 IRQ_CMD_ADDR    = $effc
@@ -12,13 +12,14 @@ IRQ_DAT_ADDR    = $effd
 
 IRQ_CMD_READIRQ = $00
 
-.proc _nmi_int
+
+.proc nmi_int
 rti
 .endproc
 
 
-; _irq_int
-.proc _irq_int
+; irq_int
+.proc irq_int
     ; Load IRQ number
     lda #IRQ_CMD_READIRQ
     sta IRQ_CMD_ADDR