1 /* 2 * Copyright (C) 2007 Michael Brown <mbrown (at) fensystems.co.uk>. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License as 6 * published by the Free Software Foundation; either version 2 of the 7 * License, or any later version. 8 * 9 * This program is distributed in the hope that it will be useful, but 10 * WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 17 */ 18 19 FILE_LICENCE ( GPL2_OR_LATER ); 20 21 #include <gpxe/io.h> 22 #include <pic8259.h> 23 24 /** @file 25 * 26 * Minimal support for the 8259 Programmable Interrupt Controller 27 * 28 */ 29 30 /** 31 * Send non-specific EOI(s) 32 * 33 * @v irq IRQ number 34 * 35 * This seems to be inherently unsafe. 36 */ 37 static inline void send_nonspecific_eoi ( unsigned int irq ) { 38 DBG ( "Sending non-specific EOI for IRQ %d\n", irq ); 39 if ( irq >= IRQ_PIC_CUTOFF ) { 40 outb ( ICR_EOI_NON_SPECIFIC, PIC2_ICR ); 41 } 42 outb ( ICR_EOI_NON_SPECIFIC, PIC1_ICR ); 43 } 44 45 /** 46 * Send specific EOI(s) 47 * 48 * @v irq IRQ number 49 */ 50 static inline void send_specific_eoi ( unsigned int irq ) { 51 DBG ( "Sending specific EOI for IRQ %d\n", irq ); 52 if ( irq >= IRQ_PIC_CUTOFF ) { 53 outb ( ( ICR_EOI_SPECIFIC | ICR_VALUE ( CHAINED_IRQ ) ), 54 ICR_REG ( CHAINED_IRQ ) ); 55 } 56 outb ( ( ICR_EOI_SPECIFIC | ICR_VALUE ( irq ) ), ICR_REG ( irq ) ); 57 } 58 59 /** 60 * Send End-Of-Interrupt to the PIC 61 * 62 * @v irq IRQ number 63 */ 64 void send_eoi ( unsigned int irq ) { 65 send_specific_eoi ( irq ); 66 } 67
