From 1b0344660de2832b472b0a413c50ff7f111a9293 Mon Sep 17 00:00:00 2001 From: Javier Date: Sun, 30 Aug 2026 02:21:09 +0200 Subject: first steps towards (optional) serial mouse support --- pic.h | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 pic.h (limited to 'pic.h') diff --git a/pic.h b/pic.h new file mode 100644 index 0000000..0d87369 --- /dev/null +++ b/pic.h @@ -0,0 +1,59 @@ +/* + * VBMouse - Programmable Interrupt Controller routines + * Copyright (C) 2022 Javier S. Pedro + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#ifndef PIC_H +#define PIC_H + +#include + +// TODO Currently do not support secondary PIC + +enum { + PIC1_CMD_IOPORT = 0x20, + PIC1_DATA_IOPORT = PIC1_CMD_IOPORT+1, + PIC2_CMD_IOPORT = 0xA0, + PIC2_DATA_IOPORT = PIC2_CMD_IOPORT+1, +}; + +enum PIC_CMDS { + /** End-Of-Interrupt command. */ + PIC_CMD_EOI = 0x20 +}; + +static void pic_mask_irq(unsigned irq) +{ + uint8_t mask = inp(PIC1_DATA_IOPORT); + mask |= (1 << irq); + outp(PIC1_DATA_IOPORT, mask); +} + +static void pic_unmask_irq(unsigned irq) +{ + uint8_t mask = inp(PIC1_DATA_IOPORT); + mask &= ~(1 << irq); + outp(PIC1_DATA_IOPORT, mask); +} + +static void pic_eoi_irq(unsigned irq) +{ + (void) irq; + outp(PIC1_CMD_IOPORT, PIC_CMD_EOI); +} + +#endif // PIC_H -- cgit v1.2.3