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-rw-r--r--arch/mips/alchemy/common/clocks.c93
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diff --git a/arch/mips/alchemy/common/clocks.c b/arch/mips/alchemy/common/clocks.c
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1/*
2 * BRIEF MODULE DESCRIPTION
3 * Simple Au1xx0 clocks routines.
4 *
5 * Copyright 2001, 2008 MontaVista Software Inc.
6 * Author: MontaVista Software, Inc. <source@mvista.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 *
13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
14 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
15 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
16 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
19 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 *
24 * You should have received a copy of the GNU General Public License along
25 * with this program; if not, write to the Free Software Foundation, Inc.,
26 * 675 Mass Ave, Cambridge, MA 02139, USA.
27 */
28
29#include <linux/module.h>
30#include <asm/mach-au1x00/au1000.h>
31
32static unsigned int au1x00_clock; /* Hz */
33static unsigned int lcd_clock; /* KHz */
34static unsigned long uart_baud_base;
35
36/*
37 * Set the au1000_clock
38 */
39void set_au1x00_speed(unsigned int new_freq)
40{
41 au1x00_clock = new_freq;
42}
43
44unsigned int get_au1x00_speed(void)
45{
46 return au1x00_clock;
47}
48EXPORT_SYMBOL(get_au1x00_speed);
49
50/*
51 * The UART baud base is not known at compile time ... if
52 * we want to be able to use the same code on different
53 * speed CPUs.
54 */
55unsigned long get_au1x00_uart_baud_base(void)
56{
57 return uart_baud_base;
58}
59
60void set_au1x00_uart_baud_base(unsigned long new_baud_base)
61{
62 uart_baud_base = new_baud_base;
63}
64
65/*
66 * Calculate the Au1x00's LCD clock based on the current
67 * cpu clock and the system bus clock, and try to keep it
68 * below 40 MHz (the Pb1000 board can lock-up if the LCD
69 * clock is over 40 MHz).
70 */
71void set_au1x00_lcd_clock(void)
72{
73 unsigned int static_cfg0;
74 unsigned int sys_busclk = (get_au1x00_speed() / 1000) /
75 ((int)(au_readl(SYS_POWERCTRL) & 0x03) + 2);
76
77 static_cfg0 = au_readl(MEM_STCFG0);
78
79 if (static_cfg0 & (1 << 11))
80 lcd_clock = sys_busclk / 5; /* note: BCLK switching fails with D5 */
81 else
82 lcd_clock = sys_busclk / 4;
83
84 if (lcd_clock > 50000) /* Epson MAX */
85 printk(KERN_WARNING "warning: LCD clock too high (%u KHz)\n",
86 lcd_clock);
87}
88
89unsigned int get_au1x00_lcd_clock(void)
90{
91 return lcd_clock;
92}
93EXPORT_SYMBOL(get_au1x00_lcd_clock);