| Greg Hartman | 76d05dc | 2016-11-23 15:51:27 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2007 Michael Brown <mbrown@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 | } |