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-rw-r--r--arch/mips/mti-malta/malta-time.c163
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diff --git a/arch/mips/mti-malta/malta-time.c b/arch/mips/mti-malta/malta-time.c
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+/*
+ * Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 1999,2000 MIPS Technologies, Inc. All rights reserved.
+ *
+ * This program is free software; you can distribute it and/or modify it
+ * under the terms of the GNU General Public License (Version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * 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.,
+ * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Setting up the clock on the MIPS boards.
+ */
+
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+#include <linux/mc146818rtc.h>
+
+#include <asm/mipsregs.h>
+#include <asm/mipsmtregs.h>
+#include <asm/hardirq.h>
+#include <asm/i8253.h>
+#include <asm/irq.h>
+#include <asm/div64.h>
+#include <asm/cpu.h>
+#include <asm/time.h>
+#include <asm/mc146818-time.h>
+#include <asm/msc01_ic.h>
+
+#include <asm/mips-boards/generic.h>
+#include <asm/mips-boards/prom.h>
+
+#include <asm/mips-boards/maltaint.h>
+
+unsigned long cpu_khz;
+
+static int mips_cpu_timer_irq;
+static int mips_cpu_perf_irq;
+extern int cp0_perfcount_irq;
+
+static void mips_timer_dispatch(void)
+{
+ do_IRQ(mips_cpu_timer_irq);
+}
+
+static void mips_perf_dispatch(void)
+{
+ do_IRQ(mips_cpu_perf_irq);
+}
+
+/*
+ * Estimate CPU frequency. Sets mips_hpt_frequency as a side-effect
+ */
+static unsigned int __init estimate_cpu_frequency(void)
+{
+ unsigned int prid = read_c0_prid() & 0xffff00;
+ unsigned int count;
+
+ unsigned long flags;
+ unsigned int start;
+
+ local_irq_save(flags);
+
+ /* Start counter exactly on falling edge of update flag */
+ while (CMOS_READ(RTC_REG_A) & RTC_UIP);
+ while (!(CMOS_READ(RTC_REG_A) & RTC_UIP));
+
+ /* Start r4k counter. */
+ start = read_c0_count();
+
+ /* Read counter exactly on falling edge of update flag */
+ while (CMOS_READ(RTC_REG_A) & RTC_UIP);
+ while (!(CMOS_READ(RTC_REG_A) & RTC_UIP));
+
+ count = read_c0_count() - start;
+
+ /* restore interrupts */
+ local_irq_restore(flags);
+
+ mips_hpt_frequency = count;
+ if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) &&
+ (prid != (PRID_COMP_MIPS | PRID_IMP_25KF)))
+ count *= 2;
+
+ count += 5000; /* round */
+ count -= count%10000;
+
+ return count;
+}
+
+unsigned long read_persistent_clock(void)
+{
+ return mc146818_get_cmos_time();
+}
+
+static void __init plat_perf_setup(void)
+{
+#ifdef MSC01E_INT_BASE
+ if (cpu_has_veic) {
+ set_vi_handler(MSC01E_INT_PERFCTR, mips_perf_dispatch);
+ mips_cpu_perf_irq = MSC01E_INT_BASE + MSC01E_INT_PERFCTR;
+ } else
+#endif
+ if (cp0_perfcount_irq >= 0) {
+ if (cpu_has_vint)
+ set_vi_handler(cp0_perfcount_irq, mips_perf_dispatch);
+ mips_cpu_perf_irq = MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
+#ifdef CONFIG_SMP
+ set_irq_handler(mips_cpu_perf_irq, handle_percpu_irq);
+#endif
+ }
+}
+
+unsigned int __cpuinit get_c0_compare_int(void)
+{
+#ifdef MSC01E_INT_BASE
+ if (cpu_has_veic) {
+ set_vi_handler(MSC01E_INT_CPUCTR, mips_timer_dispatch);
+ mips_cpu_timer_irq = MSC01E_INT_BASE + MSC01E_INT_CPUCTR;
+ } else
+#endif
+ {
+ if (cpu_has_vint)
+ set_vi_handler(cp0_compare_irq, mips_timer_dispatch);
+ mips_cpu_timer_irq = MIPS_CPU_IRQ_BASE + cp0_compare_irq;
+ }
+
+ return mips_cpu_timer_irq;
+}
+
+void __init plat_time_init(void)
+{
+ unsigned int est_freq;
+
+ /* Set Data mode - binary. */
+ CMOS_WRITE(CMOS_READ(RTC_CONTROL) | RTC_DM_BINARY, RTC_CONTROL);
+
+ est_freq = estimate_cpu_frequency();
+
+ printk("CPU frequency %d.%02d MHz\n", est_freq/1000000,
+ (est_freq%1000000)*100/1000000);
+
+ cpu_khz = est_freq / 1000;
+
+ mips_scroll_message();
+#ifdef CONFIG_I8253 /* Only Malta has a PIT */
+ setup_pit_timer();
+#endif
+
+ plat_perf_setup();
+}