From b69883172b837d3abff02beb49a2adad6465ba6d Mon Sep 17 00:00:00 2001 From: Ben Pfaff Date: Wed, 3 Dec 2008 21:41:18 -0800 Subject: [PATCH] Rewrite the I/O port code. The contents of these functions was derived from code used in the Massachusetts Institute of Technology's 6.828 advanced operating systems course. I deleted the contents of these functions and then rewrote them from scratch without reference to the earlier code, working only from the function comments (which I wrote earlier). --- src/threads/io.h | 82 +++++++----------------------------------------- 1 file changed, 12 insertions(+), 70 deletions(-) diff --git a/src/threads/io.h b/src/threads/io.h index b493299..30d52da 100644 --- a/src/threads/io.h +++ b/src/threads/io.h @@ -1,43 +1,3 @@ -/* This file is derived from source code used in MIT's 6.828 - course. The original copyright notice is reproduced in full - below. */ - -/* - * Copyright (C) 1997 Massachusetts Institute of Technology - * - * This software is being provided by the copyright holders under the - * following license. By obtaining, using and/or copying this software, - * you agree that you have read, understood, and will comply with the - * following terms and conditions: - * - * Permission to use, copy, modify, distribute, and sell this software - * and its documentation for any purpose and without fee or royalty is - * hereby granted, provided that the full text of this NOTICE appears on - * ALL copies of the software and documentation or portions thereof, - * including modifications, that you make. - * - * THIS SOFTWARE IS PROVIDED "AS IS," AND COPYRIGHT HOLDERS MAKE NO - * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED. BY WAY OF EXAMPLE, - * BUT NOT LIMITATION, COPYRIGHT HOLDERS MAKE NO REPRESENTATIONS OR - * WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR - * THAT THE USE OF THE SOFTWARE OR DOCUMENTATION WILL NOT INFRINGE ANY - * THIRD PARTY PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS. COPYRIGHT - * HOLDERS WILL BEAR NO LIABILITY FOR ANY USE OF THIS SOFTWARE OR - * DOCUMENTATION. - * - * The name and trademarks of copyright holders may NOT be used in - * advertising or publicity pertaining to the software without specific, - * written prior permission. Title to copyright in this software and any - * associated documentation will at all times remain with copyright - * holders. See the file AUTHORS which should have accompanied this software - * for a list of all copyright holders. - * - * This file may be derived from previously copyrighted software. This - * copyright applies only to those changes made by the copyright - * holders listed in the AUTHORS file. The rest of this file is covered by - * the copyright notices, if any, listed below. - */ - #ifndef THREADS_IO_H #define THREADS_IO_H @@ -50,7 +10,7 @@ inb (uint16_t port) { /* See [IA32-v2a] "IN". */ uint8_t data; - asm volatile ("inb %w1,%0" : "=a" (data) : "d" (port)); + asm volatile ("inb %w1, %b0" : "=a" (data) : "Nd" (port)); return data; } @@ -60,10 +20,7 @@ static inline void insb (uint16_t port, void *addr, size_t cnt) { /* See [IA32-v2a] "INS". */ - asm volatile ("cld; repne; insb" - : "=D" (addr), "=c" (cnt) - : "d" (port), "0" (addr), "1" (cnt) - : "memory", "cc"); + asm volatile ("rep insb" : "+D" (addr), "+c" (cnt) : "d" (port) : "memory"); } /* Reads and returns 16 bits from PORT. */ @@ -72,7 +29,7 @@ inw (uint16_t port) { uint16_t data; /* See [IA32-v2a] "IN". */ - asm volatile ("inw %w1,%0" : "=a" (data) : "d" (port)); + asm volatile ("inw %w1, %w0" : "=a" (data) : "Nd" (port)); return data; } @@ -82,10 +39,7 @@ static inline void insw (uint16_t port, void *addr, size_t cnt) { /* See [IA32-v2a] "INS". */ - asm volatile ("cld; repne; insw" - : "=D" (addr), "=c" (cnt) - : "d" (port), "0" (addr), "1" (cnt) - : "memory", "cc"); + asm volatile ("rep insw" : "+D" (addr), "+c" (cnt) : "d" (port) : "memory"); } /* Reads and returns 32 bits from PORT. */ @@ -94,7 +48,7 @@ inl (uint16_t port) { /* See [IA32-v2a] "IN". */ uint32_t data; - asm volatile ("inl %w1,%0" : "=a" (data) : "d" (port)); + asm volatile ("inl %w1, %0" : "=a" (data) : "Nd" (port)); return data; } @@ -104,10 +58,7 @@ static inline void insl (uint16_t port, void *addr, size_t cnt) { /* See [IA32-v2a] "INS". */ - asm volatile ("cld; repne; insl" - : "=D" (addr), "=c" (cnt) - : "d" (port), "0" (addr), "1" (cnt) - : "memory", "cc"); + asm volatile ("rep insl" : "+D" (addr), "+c" (cnt) : "d" (port) : "memory"); } /* Writes byte DATA to PORT. */ @@ -115,7 +66,7 @@ static inline void outb (uint16_t port, uint8_t data) { /* See [IA32-v2b] "OUT". */ - asm volatile ("outb %0,%w1" : : "a" (data), "d" (port)); + asm volatile ("outb %b0, %w1" : : "a" (data), "Nd" (port)); } /* Writes to PORT each byte of data in the CNT-byte buffer @@ -124,10 +75,7 @@ static inline void outsb (uint16_t port, const void *addr, size_t cnt) { /* See [IA32-v2b] "OUTS". */ - asm volatile ("cld; repne; outsb" - : "=S" (addr), "=c" (cnt) - : "d" (port), "0" (addr), "1" (cnt) - : "cc"); + asm volatile ("rep outsb" : "+S" (addr), "+c" (cnt) : "d" (port)); } /* Writes the 16-bit DATA to PORT. */ @@ -135,7 +83,7 @@ static inline void outw (uint16_t port, uint16_t data) { /* See [IA32-v2b] "OUT". */ - asm volatile ("outw %0,%w1" : : "a" (data), "d" (port)); + asm volatile ("outw %w0, %w1" : : "a" (data), "Nd" (port)); } /* Writes to PORT each 16-bit unit (halfword) of data in the @@ -144,10 +92,7 @@ static inline void outsw (uint16_t port, const void *addr, size_t cnt) { /* See [IA32-v2b] "OUTS". */ - asm volatile ("cld; repne; outsw" - : "=S" (addr), "=c" (cnt) - : "d" (port), "0" (addr), "1" (cnt) - : "cc"); + asm volatile ("rep outsw" : "+S" (addr), "+c" (cnt) : "d" (port)); } /* Writes the 32-bit DATA to PORT. */ @@ -155,7 +100,7 @@ static inline void outl (uint16_t port, uint32_t data) { /* See [IA32-v2b] "OUT". */ - asm volatile ("outl %0,%w1" : : "a" (data), "d" (port)); + asm volatile ("outl %0, %w1" : : "a" (data), "Nd" (port)); } /* Writes to PORT each 32-bit unit (word) of data in the CNT-word @@ -164,10 +109,7 @@ static inline void outsl (uint16_t port, const void *addr, size_t cnt) { /* See [IA32-v2b] "OUTS". */ - asm volatile ("cld; repne; outsl" - : "=S" (addr), "=c" (cnt) - : "d" (port), "0" (addr), "1" (cnt) - : "cc"); + asm volatile ("rep outsl" : "+S" (addr), "+c" (cnt) : "d" (port)); } #endif /* threads/io.h */ -- 2.30.2