mirror of https://gitee.com/openkylin/linux.git
94 lines
2.8 KiB
C
94 lines
2.8 KiB
C
/*
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* BRIEF MODULE DESCRIPTION
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* Simple Au1xx0 clocks routines.
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*
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* Copyright 2001, 2008 MontaVista Software Inc.
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* Author: MontaVista Software, Inc. <source@mvista.com>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation; either version 2 of the License, or (at your
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* option) any later version.
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*
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* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
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* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#include <linux/module.h>
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#include <asm/mach-au1x00/au1000.h>
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static unsigned int au1x00_clock; /* Hz */
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static unsigned int lcd_clock; /* KHz */
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static unsigned long uart_baud_base;
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/*
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* Set the au1000_clock
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*/
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void set_au1x00_speed(unsigned int new_freq)
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{
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au1x00_clock = new_freq;
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}
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unsigned int get_au1x00_speed(void)
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{
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return au1x00_clock;
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}
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EXPORT_SYMBOL(get_au1x00_speed);
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/*
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* The UART baud base is not known at compile time ... if
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* we want to be able to use the same code on different
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* speed CPUs.
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*/
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unsigned long get_au1x00_uart_baud_base(void)
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{
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return uart_baud_base;
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}
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void set_au1x00_uart_baud_base(unsigned long new_baud_base)
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{
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uart_baud_base = new_baud_base;
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}
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/*
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* Calculate the Au1x00's LCD clock based on the current
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* cpu clock and the system bus clock, and try to keep it
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* below 40 MHz (the Pb1000 board can lock-up if the LCD
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* clock is over 40 MHz).
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*/
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void set_au1x00_lcd_clock(void)
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{
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unsigned int static_cfg0;
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unsigned int sys_busclk = (get_au1x00_speed() / 1000) /
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((int)(au_readl(SYS_POWERCTRL) & 0x03) + 2);
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static_cfg0 = au_readl(MEM_STCFG0);
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if (static_cfg0 & (1 << 11))
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lcd_clock = sys_busclk / 5; /* note: BCLK switching fails with D5 */
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else
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lcd_clock = sys_busclk / 4;
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if (lcd_clock > 50000) /* Epson MAX */
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printk(KERN_WARNING "warning: LCD clock too high (%u KHz)\n",
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lcd_clock);
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}
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unsigned int get_au1x00_lcd_clock(void)
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{
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return lcd_clock;
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}
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EXPORT_SYMBOL(get_au1x00_lcd_clock);
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