Working i386 paging and liballoc

kernel/platform/i386_pc/sys/pic.c

@@ -0,0 +1,84 @@
+/*
+Copyright 2025 Kamil Kowalczyk
+
+Redistribution and use in source and binary forms, with or
+without modification, are permitted provided that the following
+conditions are met:
+
+1. Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright
+notice, this list of conditions and the following disclaimer in the
+documentation and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+“AS IS” AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <sys/pic.h>
+#include <sys/ioport.h>
+
+#define PIC1        0x20
+#define PIC2        0xA0
+#define PIC1_CMD    PIC1
+#define PIC1_DATA   (PIC1 + 1)
+#define PIC2_CMD    PIC2
+#define PIC2_DATA   (PIC2 + 1)
+
+#define ICW1_ICW4     0x01
+#define ICW1_SINGLE   0x02
+#define ICW1_INTVL4   0x04
+#define ICW1_LEVEL    0x08
+#define ICW1_INIT     0x10
+
+#define ICW4_8086     0x01
+#define ICW4_AUTO     0x02
+#define ICW4_BUFSLAVE 0x08
+#define ICW4_BUFMASER 0x0C
+#define ICW4_SFNM     0x10
+
+#define CASCADE_IRQ   2
+
+void pic_init(void) {
+  // remap & disable
+
+  ioport_out8(PIC1_CMD, ICW1_INIT | ICW1_ICW4);
+  ioport_wait();
+
+  ioport_out8(PIC2_CMD, ICW1_INIT | ICW1_ICW4);
+  ioport_wait();
+
+  ioport_out8(PIC1_DATA, 4);
+  ioport_wait();
+
+  ioport_out8(PIC2_DATA, 2);
+  ioport_wait();
+
+  ioport_out8(PIC1_DATA, 1<<CASCADE_IRQ);
+  ioport_wait();
+  ioport_out8(PIC2_DATA, 2);
+  ioport_wait();
+
+  ioport_out8(PIC1_DATA, ICW4_8086);
+  ioport_wait();
+
+  ioport_out8(PIC2_DATA, ICW4_8086);
+  ioport_wait();
+
+  ioport_out8(PIC1_DATA, 0xFF);
+  ioport_out8(PIC2_DATA, 0xFF);
+}