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| author | fishsoupisgood <github@madingley.org> | 2019-04-29 01:17:54 +0100 |
|---|---|---|
| committer | fishsoupisgood <github@madingley.org> | 2019-05-27 03:43:43 +0100 |
| commit | 3f2546b2ef55b661fd8dd69682b38992225e86f6 (patch) | |
| tree | 65ca85f13617aee1dce474596800950f266a456c /roms/u-boot/arch/x86/lib/pcat_timer.c | |
| download | qemu-master.tar.gz qemu-master.tar.bz2 qemu-master.zip | |
Diffstat (limited to 'roms/u-boot/arch/x86/lib/pcat_timer.c')
| -rw-r--r-- | roms/u-boot/arch/x86/lib/pcat_timer.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/roms/u-boot/arch/x86/lib/pcat_timer.c b/roms/u-boot/arch/x86/lib/pcat_timer.c new file mode 100644 index 00000000..3545a504 --- /dev/null +++ b/roms/u-boot/arch/x86/lib/pcat_timer.c @@ -0,0 +1,27 @@ +/* + * (C) Copyright 2002 + * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <asm/io.h> +#include <asm/i8254.h> + +#define TIMER2_VALUE 0x0a8e /* 440Hz */ + +int pcat_timer_init(void) +{ + /* + * initialize 2, used to drive the speaker + * (to start a beep: write 3 to port 0x61, + * to stop it again: write 0) + */ + outb(PIT_CMD_CTR2 | PIT_CMD_BOTH | PIT_CMD_MODE3, + PIT_BASE + PIT_COMMAND); + outb(TIMER2_VALUE & 0xff, PIT_BASE + PIT_T2); + outb(TIMER2_VALUE >> 8, PIT_BASE + PIT_T2); + + return 0; +} |