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Diffstat (limited to 'arch/mips/alchemy/common/clocks.c')
-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);