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-rw-r--r--arch/mips/philips/pnx8550/common/time.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/mips/philips/pnx8550/common/time.c b/arch/mips/philips/pnx8550/common/time.c
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+++ b/arch/mips/philips/pnx8550/common/time.c
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+/*
+ * Copyright 2001, 2002, 2003 MontaVista Software Inc.
+ * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
+ *
+ * Common time service routines for MIPS machines. See
+ * Documents/MIPS/README.txt.
+ *
+ * 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.
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/param.h>
+#include <linux/time.h>
+#include <linux/timer.h>
+#include <linux/smp.h>
+#include <linux/kernel_stat.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+
+#include <asm/bootinfo.h>
+#include <asm/cpu.h>
+#include <asm/time.h>
+#include <asm/hardirq.h>
+#include <asm/div64.h>
+#include <asm/debug.h>
+
+#include <int.h>
+#include <cm.h>
+
+extern unsigned int mips_hpt_frequency;
+
+/*
+ * pnx8550_time_init() - it does the following things:
+ *
+ * 1) board_time_init() -
+ * a) (optional) set up RTC routines,
+ * b) (optional) calibrate and set the mips_hpt_frequency
+ * (only needed if you intended to use fixed_rate_gettimeoffset
+ * or use cpu counter as timer interrupt source)
+ */
+
+void pnx8550_time_init(void)
+{
+ unsigned int n;
+ unsigned int m;
+ unsigned int p;
+ unsigned int pow2p;
+
+ /* PLL0 sets MIPS clock (PLL1 <=> TM1, PLL6 <=> TM2, PLL5 <=> mem) */
+ /* (but only if CLK_MIPS_CTL select value [bits 3:1] is 1: FIXME) */
+
+ n = (PNX8550_CM_PLL0_CTL & PNX8550_CM_PLL_N_MASK) >> 16;
+ m = (PNX8550_CM_PLL0_CTL & PNX8550_CM_PLL_M_MASK) >> 8;
+ p = (PNX8550_CM_PLL0_CTL & PNX8550_CM_PLL_P_MASK) >> 2;
+ pow2p = (1 << p);
+
+ db_assert(m != 0 && pow2p != 0);
+
+ /*
+ * Compute the frequency as in the PNX8550 User Manual 1.0, p.186
+ * (a.k.a. 8-10). Divide by HZ for a timer offset that results in
+ * HZ timer interrupts per second.
+ */
+ mips_hpt_frequency = 27UL * ((1000000UL * n)/(m * pow2p));
+}
+
+/*
+ * pnx8550_timer_setup() - it does the following things:
+ *
+ * 5) board_timer_setup() -
+ * a) (optional) over-write any choices made above by time_init().
+ * b) machine specific code should setup the timer irqaction.
+ * c) enable the timer interrupt
+ */
+
+void __init pnx8550_timer_setup(struct irqaction *irq)
+{
+ int configPR;
+
+ setup_irq(PNX8550_INT_TIMER1, irq);
+
+ /* Start timer1 */
+ configPR = read_c0_config7();
+ configPR &= ~0x00000008;
+ write_c0_config7(configPR);
+
+ /* Timer 2 stop */
+ configPR = read_c0_config7();
+ configPR |= 0x00000010;
+ write_c0_config7(configPR);
+
+ write_c0_count2(0);
+ write_c0_compare2(0xffffffff);
+
+ /* Timer 3 stop */
+ configPR = read_c0_config7();
+ configPR |= 0x00000020;
+ write_c0_config7(configPR);
+}