1/* 2 * BRIEF MODULE DESCRIPTION 3 * Simple Au1000 clocks routines. 4 * 5 * Copyright 2001 MontaVista Software Inc. 6 * Author: MontaVista Software, Inc. 7 * ppopov@mvista.com or source@mvista.com 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by the 11 * Free Software Foundation; either version 2 of the License, or (at your 12 * option) any later version. 13 * 14 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED 15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 16 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN 17 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 20 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 21 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 * 25 * You should have received a copy of the GNU General Public License along 26 * with this program; if not, write to the Free Software Foundation, Inc., 27 * 675 Mass Ave, Cambridge, MA 02139, USA. 28 */ 29 30#include <linux/module.h> 31#include <asm/mach-au1x00/au1000.h> 32 33static unsigned int au1x00_clock; // Hz 34static unsigned int lcd_clock; // KHz 35static unsigned long uart_baud_base; 36 37/* 38 * Set the au1000_clock 39 */ 40void set_au1x00_speed(unsigned int new_freq) 41{ 42 au1x00_clock = new_freq; 43} 44 45unsigned int get_au1x00_speed(void) 46{ 47 return au1x00_clock; 48} 49 50 51 52/* 53 * The UART baud base is not known at compile time ... if 54 * we want to be able to use the same code on different 55 * speed CPUs. 56 */ 57unsigned long get_au1x00_uart_baud_base(void) 58{ 59 return uart_baud_base; 60} 61 62void set_au1x00_uart_baud_base(unsigned long new_baud_base) 63{ 64 uart_baud_base = new_baud_base; 65} 66 67/* 68 * Calculate the Au1x00's LCD clock based on the current 69 * cpu clock and the system bus clock, and try to keep it 70 * below 40 MHz (the Pb1000 board can lock-up if the LCD 71 * clock is over 40 MHz). 72 */ 73void set_au1x00_lcd_clock(void) 74{ 75 unsigned int static_cfg0; 76 unsigned int sys_busclk = 77 (get_au1x00_speed()/1000) / 78 ((int)(au_readl(SYS_POWERCTRL)&0x03) + 2); 79 80 static_cfg0 = au_readl(MEM_STCFG0); 81 82 if (static_cfg0 & (1<<11)) 83 lcd_clock = sys_busclk / 5; /* note: BCLK switching fails with D5 */ 84 else 85 lcd_clock = sys_busclk / 4; 86 87 if (lcd_clock > 50000) /* Epson MAX */ 88 printk("warning: LCD clock too high (%d KHz)\n", lcd_clock); 89} 90 91unsigned int get_au1x00_lcd_clock(void) 92{ 93 return lcd_clock; 94} 95 96EXPORT_SYMBOL(get_au1x00_lcd_clock); 97