diff options
Diffstat (limited to 'contrib/syslinux-4.02/gpxe/src/arch/i386/core/pic8259.c')
-rw-r--r-- | contrib/syslinux-4.02/gpxe/src/arch/i386/core/pic8259.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/arch/i386/core/pic8259.c b/contrib/syslinux-4.02/gpxe/src/arch/i386/core/pic8259.c new file mode 100644 index 0000000..1e2d23c --- /dev/null +++ b/contrib/syslinux-4.02/gpxe/src/arch/i386/core/pic8259.c @@ -0,0 +1,66 @@ +/* + * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>. + * + * 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 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., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +FILE_LICENCE ( GPL2_OR_LATER ); + +#include <gpxe/io.h> +#include <pic8259.h> + +/** @file + * + * Minimal support for the 8259 Programmable Interrupt Controller + * + */ + +/** + * Send non-specific EOI(s) + * + * @v irq IRQ number + * + * This seems to be inherently unsafe. + */ +static inline void send_nonspecific_eoi ( unsigned int irq ) { + DBG ( "Sending non-specific EOI for IRQ %d\n", irq ); + if ( irq >= IRQ_PIC_CUTOFF ) { + outb ( ICR_EOI_NON_SPECIFIC, PIC2_ICR ); + } + outb ( ICR_EOI_NON_SPECIFIC, PIC1_ICR ); +} + +/** + * Send specific EOI(s) + * + * @v irq IRQ number + */ +static inline void send_specific_eoi ( unsigned int irq ) { + DBG ( "Sending specific EOI for IRQ %d\n", irq ); + if ( irq >= IRQ_PIC_CUTOFF ) { + outb ( ( ICR_EOI_SPECIFIC | ICR_VALUE ( CHAINED_IRQ ) ), + ICR_REG ( CHAINED_IRQ ) ); + } + outb ( ( ICR_EOI_SPECIFIC | ICR_VALUE ( irq ) ), ICR_REG ( irq ) ); +} + +/** + * Send End-Of-Interrupt to the PIC + * + * @v irq IRQ number + */ +void send_eoi ( unsigned int irq ) { + send_specific_eoi ( irq ); +} |