| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | /* |
| 2 | * (C) Copyright 2002 |
| 3 | * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se> |
| 4 | * |
| 5 | * SPDX-License-Identifier: GPL-2.0+ |
| 6 | */ |
| 7 | |
| 8 | #include <common.h> |
| 9 | #include <asm/io.h> |
| 10 | #include <asm/i8254.h> |
| 11 | |
| 12 | #define TIMER2_VALUE 0x0a8e /* 440Hz */ |
| 13 | |
| 14 | int pcat_timer_init(void) |
| 15 | { |
| 16 | /* |
| 17 | * initialize 2, used to drive the speaker |
| 18 | * (to start a beep: write 3 to port 0x61, |
| 19 | * to stop it again: write 0) |
| 20 | */ |
| 21 | outb(PIT_CMD_CTR2 | PIT_CMD_BOTH | PIT_CMD_MODE3, |
| 22 | PIT_BASE + PIT_COMMAND); |
| 23 | outb(TIMER2_VALUE & 0xff, PIT_BASE + PIT_T2); |
| 24 | outb(TIMER2_VALUE >> 8, PIT_BASE + PIT_T2); |
| 25 | |
| 26 | return 0; |
| 27 | } |