X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=ld45_start_nothing;a=blobdiff_plain;f=src%2Fintr.inc;fp=src%2Fintr.inc;h=95b18d6c9ba8cddf09e9337ca778a1d3fe69fbc1;hp=0000000000000000000000000000000000000000;hb=6bbbb04131204b22367677209d7de8c3f906d0e2;hpb=8a43487117b23806e478603f3c8ab72e37cd1882

diff --git a/src/intr.inc b/src/intr.inc
new file mode 100644
index 0000000..95b18d6
--- /dev/null
+++ b/src/intr.inc
@@ -0,0 +1,45 @@
+; vi:filetype=nasm ts=8 sts=8 sw=8:
+
+%define IRQ_OFFSET	32
+%define IRQ_TO_INTR(x)	((x) + IRQ_OFFSET)
+%define INTR_TO_IRQ(x)	((x) - IRQ_OFFSET)
+
+%macro set_irq_vector 2
+	push dword IRQ_TO_INTR(%1)
+	push dword %2
+	call set_intr
+%endmacro
+
+%macro mask_irq 1
+%if %1 < 8
+%assign port PIC1_DATA
+%assign mask (1 << %1)
+%else
+%assign port PIC2_DATA
+%assign mask (1 << (%1 - 8))
+%endif
+	in al, port
+	or al, mask
+	out port, al
+%endmacro
+
+%macro unmask_irq 1
+%if %1 < 8
+%assign port PIC1_DATA
+%assign mask ~(1 << %1)
+%else
+%assign port PIC2_DATA
+%assign mask ~(1 << (%1 - 8))
+%endif
+	in al, port
+	and al, mask
+	out port, al
+%endmacro
+
+%macro end_of_irq 1
+	mov al, OCW2_EOI
+%if %1 >= 8
+	out PIC2_CMD, al
+%endif
+	out PIC1_CMD, al
+%endmacro