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-rw-r--r--arch/mips/alchemy/common/clocks.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/arch/mips/alchemy/common/clocks.c b/arch/mips/alchemy/common/clocks.c
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+++ b/arch/mips/alchemy/common/clocks.c
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+/*
+ * BRIEF MODULE DESCRIPTION
+ *	Simple Au1xx0 clocks routines.
+ *
+ * Copyright 2001, 2008 MontaVista Software Inc.
+ * Author: MontaVista Software, Inc. <source@mvista.com>
+ *
+ *  This program is free software; you can redistribute	 it and/or modify it
+ *  under  the terms of	 the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the	License, or (at your
+ *  option) any later version.
+ *
+ *  THIS  SOFTWARE  IS PROVIDED	  ``AS	IS'' AND   ANY	EXPRESS OR IMPLIED
+ *  WARRANTIES,	  INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
+ *  NO	EVENT  SHALL   THE AUTHOR  BE	 LIABLE FOR ANY	  DIRECT, INDIRECT,
+ *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ *  NOT LIMITED	  TO, PROCUREMENT OF  SUBSTITUTE GOODS	OR SERVICES; LOSS OF
+ *  USE, DATA,	OR PROFITS; OR	BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ *  ANY THEORY OF LIABILITY, WHETHER IN	 CONTRACT, STRICT LIABILITY, OR TORT
+ *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *  You should have received a copy of the  GNU General Public License along
+ *  with this program; if not, write  to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/module.h>
+#include <asm/mach-au1x00/au1000.h>
+
+static unsigned int au1x00_clock; /*  Hz */
+static unsigned int lcd_clock;    /* KHz */
+static unsigned long uart_baud_base;
+
+/*
+ * Set the au1000_clock
+ */
+void set_au1x00_speed(unsigned int new_freq)
+{
+	au1x00_clock = new_freq;
+}
+
+unsigned int get_au1x00_speed(void)
+{
+	return au1x00_clock;
+}
+EXPORT_SYMBOL(get_au1x00_speed);
+
+/*
+ * The UART baud base is not known at compile time ... if
+ * we want to be able to use the same code on different
+ * speed CPUs.
+ */
+unsigned long get_au1x00_uart_baud_base(void)
+{
+	return uart_baud_base;
+}
+
+void set_au1x00_uart_baud_base(unsigned long new_baud_base)
+{
+	uart_baud_base = new_baud_base;
+}
+
+/*
+ * Calculate the Au1x00's LCD clock based on the current
+ * cpu clock and the system bus clock, and try to keep it
+ * below 40 MHz (the Pb1000 board can lock-up if the LCD
+ * clock is over 40 MHz).
+ */
+void set_au1x00_lcd_clock(void)
+{
+	unsigned int static_cfg0;
+	unsigned int sys_busclk = (get_au1x00_speed() / 1000) /
+				  ((int)(au_readl(SYS_POWERCTRL) & 0x03) + 2);
+
+	static_cfg0 = au_readl(MEM_STCFG0);
+
+	if (static_cfg0 & (1 << 11))
+		lcd_clock = sys_busclk / 5; /* note: BCLK switching fails with D5 */
+	else
+		lcd_clock = sys_busclk / 4;
+
+	if (lcd_clock > 50000) /* Epson MAX */
+		printk(KERN_WARNING "warning: LCD clock too high (%u KHz)\n",
+				    lcd_clock);
+}
+
+unsigned int get_au1x00_lcd_clock(void)
+{
+	return lcd_clock;
+}
+EXPORT_SYMBOL(get_au1x00_lcd_clock);