Initial import

1 files changed, 211 insertions, 0 deletions

diff --git a/arch/mips/mti-malta/malta-time.c b/arch/mips/mti-malta/malta-time.c
new file mode 100644
index 000000000..185e68261
--- /dev/null
+++ b/arch/mips/mti-malta/malta-time.c
@@ -0,0 +1,211 @@
+/*
+ * 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/i8253.h>
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/irqchip/mips-gic.h>
+#include <linux/timex.h>
+#include <linux/mc146818rtc.h>
+
+#include <asm/cpu.h>
+#include <asm/mipsregs.h>
+#include <asm/mipsmtregs.h>
+#include <asm/hardirq.h>
+#include <asm/irq.h>
+#include <asm/div64.h>
+#include <asm/setup.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/maltaint.h>
+
+static int mips_cpu_timer_irq;
+static int mips_cpu_perf_irq;
+extern int cp0_perfcount_irq;
+
+static unsigned int gic_frequency;
+
+static void mips_timer_dispatch(void)
+{
+	do_IRQ(mips_cpu_timer_irq);
+}
+
+static void mips_perf_dispatch(void)
+{
+	do_IRQ(mips_cpu_perf_irq);
+}
+
+static unsigned int freqround(unsigned int freq, unsigned int amount)
+{
+	freq += amount;
+	freq -= freq % (amount*2);
+	return freq;
+}
+
+/*
+ * Estimate CPU and GIC frequencies.
+ */
+static void __init estimate_frequencies(void)
+{
+	unsigned long flags;
+	unsigned int count, start;
+	cycle_t giccount = 0, gicstart = 0;
+
+#if defined(CONFIG_KVM_GUEST) && CONFIG_KVM_GUEST_TIMER_FREQ
+	mips_hpt_frequency = CONFIG_KVM_GUEST_TIMER_FREQ * 1000000;
+	return;
+#endif
+
+	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));
+
+	/* Initialize counters. */
+	start = read_c0_count();
+	if (gic_present) {
+		gic_start_count();
+		gicstart = gic_read_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();
+	if (gic_present)
+		giccount = gic_read_count();
+
+	local_irq_restore(flags);
+
+	count -= start;
+	mips_hpt_frequency = count;
+
+	if (gic_present) {
+		giccount -= gicstart;
+		gic_frequency = giccount;
+	}
+}
+
+void read_persistent_clock(struct timespec *ts)
+{
+	ts->tv_sec = mc146818_get_cmos_time();
+	ts->tv_nsec = 0;
+}
+
+int get_c0_fdc_int(void)
+{
+	int mips_cpu_fdc_irq;
+
+	if (cpu_has_veic)
+		mips_cpu_fdc_irq = -1;
+	else if (gic_present)
+		mips_cpu_fdc_irq = gic_get_c0_fdc_int();
+	else if (cp0_fdc_irq >= 0)
+		mips_cpu_fdc_irq = MIPS_CPU_IRQ_BASE + cp0_fdc_irq;
+	else
+		mips_cpu_fdc_irq = -1;
+
+	return mips_cpu_fdc_irq;
+}
+
+int get_c0_perfcount_int(void)
+{
+	if (cpu_has_veic) {
+		set_vi_handler(MSC01E_INT_PERFCTR, mips_perf_dispatch);
+		mips_cpu_perf_irq = MSC01E_INT_BASE + MSC01E_INT_PERFCTR;
+	} else if (gic_present) {
+		mips_cpu_perf_irq = gic_get_c0_perfcount_int();
+	} else if (cp0_perfcount_irq >= 0) {
+		mips_cpu_perf_irq = MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
+	} else {
+		mips_cpu_perf_irq = -1;
+	}
+
+	return mips_cpu_perf_irq;
+}
+
+unsigned int get_c0_compare_int(void)
+{
+	if (cpu_has_veic) {
+		set_vi_handler(MSC01E_INT_CPUCTR, mips_timer_dispatch);
+		mips_cpu_timer_irq = MSC01E_INT_BASE + MSC01E_INT_CPUCTR;
+	} else if (gic_present) {
+		mips_cpu_timer_irq = gic_get_c0_compare_int();
+	} else {
+		mips_cpu_timer_irq = MIPS_CPU_IRQ_BASE + cp0_compare_irq;
+	}
+
+	return mips_cpu_timer_irq;
+}
+
+static void __init init_rtc(void)
+{
+	/* stop the clock whilst setting it up */
+	CMOS_WRITE(RTC_SET | RTC_24H, RTC_CONTROL);
+
+	/* 32KHz time base */
+	CMOS_WRITE(RTC_REF_CLCK_32KHZ, RTC_FREQ_SELECT);
+
+	/* start the clock */
+	CMOS_WRITE(RTC_24H, RTC_CONTROL);
+}
+
+void __init plat_time_init(void)
+{
+	unsigned int prid = read_c0_prid() & (PRID_COMP_MASK | PRID_IMP_MASK);
+	unsigned int freq;
+
+	init_rtc();
+	estimate_frequencies();
+
+	freq = mips_hpt_frequency;
+	if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) &&
+	    (prid != (PRID_COMP_MIPS | PRID_IMP_25KF)))
+		freq *= 2;
+	freq = freqround(freq, 5000);
+	printk("CPU frequency %d.%02d MHz\n", freq/1000000,
+	       (freq%1000000)*100/1000000);
+
+	mips_scroll_message();
+
+#ifdef CONFIG_I8253
+	/* Only Malta has a PIT. */
+	setup_pit_timer();
+#endif
+
+#ifdef CONFIG_MIPS_GIC
+	if (gic_present) {
+		freq = freqround(gic_frequency, 5000);
+		printk("GIC frequency %d.%02d MHz\n", freq/1000000,
+		       (freq%1000000)*100/1000000);
+#ifdef CONFIG_CLKSRC_MIPS_GIC
+		gic_clocksource_init(gic_frequency);
+#endif
+	}
+#endif
+}