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v3.1
  1/*
  2 * Carsten Langgaard, carstenl@mips.com
  3 * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
  4 *
  5 *  This program is free software; you can distribute it and/or modify it
  6 *  under the terms of the GNU General Public License (Version 2) as
  7 *  published by the Free Software Foundation.
  8 *
  9 *  This program is distributed in the hope it will be useful, but WITHOUT
 10 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12 *  for more details.
 13 *
 14 *  You should have received a copy of the GNU General Public License along
 15 *  with this program; if not, write to the Free Software Foundation, Inc.,
 16 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
 17 *
 18 * Setting up the clock on the MIPS boards.
 19 */
 20
 21#include <linux/types.h>
 22#include <linux/i8253.h>
 23#include <linux/init.h>
 24#include <linux/kernel_stat.h>
 25#include <linux/sched.h>
 26#include <linux/spinlock.h>
 27#include <linux/interrupt.h>
 28#include <linux/time.h>
 29#include <linux/timex.h>
 30#include <linux/mc146818rtc.h>
 31
 
 32#include <asm/mipsregs.h>
 33#include <asm/mipsmtregs.h>
 34#include <asm/hardirq.h>
 35#include <asm/irq.h>
 36#include <asm/div64.h>
 37#include <asm/cpu.h>
 38#include <asm/time.h>
 39#include <asm/mc146818-time.h>
 40#include <asm/msc01_ic.h>
 
 41
 42#include <asm/mips-boards/generic.h>
 43#include <asm/mips-boards/prom.h>
 44
 45#include <asm/mips-boards/maltaint.h>
 46
 47unsigned long cpu_khz;
 48
 49static int mips_cpu_timer_irq;
 50static int mips_cpu_perf_irq;
 51extern int cp0_perfcount_irq;
 52
 53static void mips_timer_dispatch(void)
 54{
 55	do_IRQ(mips_cpu_timer_irq);
 56}
 57
 58static void mips_perf_dispatch(void)
 59{
 60	do_IRQ(mips_cpu_perf_irq);
 61}
 62
 
 
 
 
 
 
 
 63/*
 64 * Estimate CPU frequency.  Sets mips_hpt_frequency as a side-effect
 65 */
 66static unsigned int __init estimate_cpu_frequency(void)
 67{
 68	unsigned int prid = read_c0_prid() & 0xffff00;
 69	unsigned int count;
 70
 71	unsigned long flags;
 72	unsigned int start;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 73
 74	local_irq_save(flags);
 75
 76	/* Start counter exactly on falling edge of update flag */
 77	while (CMOS_READ(RTC_REG_A) & RTC_UIP);
 78	while (!(CMOS_READ(RTC_REG_A) & RTC_UIP));
 79
 80	/* Start r4k counter. */
 81	start = read_c0_count();
 
 
 
 
 82
 83	/* Read counter exactly on falling edge of update flag */
 84	while (CMOS_READ(RTC_REG_A) & RTC_UIP);
 85	while (!(CMOS_READ(RTC_REG_A) & RTC_UIP));
 86
 87	count = read_c0_count() - start;
 
 
 
 
 88
 89	/* restore interrupts */
 90	local_irq_restore(flags);
 91
 
 92	mips_hpt_frequency = count;
 93	if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) &&
 94	    (prid != (PRID_COMP_MIPS | PRID_IMP_25KF)))
 95		count *= 2;
 96
 97	count += 5000;    /* round */
 98	count -= count%10000;
 99
100	return count;
 
 
 
 
 
101}
102
103void read_persistent_clock(struct timespec *ts)
104{
105	ts->tv_sec = mc146818_get_cmos_time();
106	ts->tv_nsec = 0;
107}
108
109static void __init plat_perf_setup(void)
110{
111#ifdef MSC01E_INT_BASE
112	if (cpu_has_veic) {
113		set_vi_handler(MSC01E_INT_PERFCTR, mips_perf_dispatch);
114		mips_cpu_perf_irq = MSC01E_INT_BASE + MSC01E_INT_PERFCTR;
115	} else
116#endif
117	if (cp0_perfcount_irq >= 0) {
118		if (cpu_has_vint)
119			set_vi_handler(cp0_perfcount_irq, mips_perf_dispatch);
120		mips_cpu_perf_irq = MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
121#ifdef CONFIG_SMP
122		irq_set_handler(mips_cpu_perf_irq, handle_percpu_irq);
123#endif
124	}
125}
126
127unsigned int __cpuinit get_c0_compare_int(void)
128{
129#ifdef MSC01E_INT_BASE
130	if (cpu_has_veic) {
131		set_vi_handler(MSC01E_INT_CPUCTR, mips_timer_dispatch);
132		mips_cpu_timer_irq = MSC01E_INT_BASE + MSC01E_INT_CPUCTR;
133	} else
134#endif
135	{
136		if (cpu_has_vint)
137			set_vi_handler(cp0_compare_irq, mips_timer_dispatch);
138		mips_cpu_timer_irq = MIPS_CPU_IRQ_BASE + cp0_compare_irq;
139	}
140
141	return mips_cpu_timer_irq;
142}
143
144void __init plat_time_init(void)
145{
146	unsigned int est_freq;
 
147
148        /* Set Data mode - binary. */
149        CMOS_WRITE(CMOS_READ(RTC_CONTROL) | RTC_DM_BINARY, RTC_CONTROL);
150
151	est_freq = estimate_cpu_frequency();
 
 
152
153	printk("CPU frequency %d.%02d MHz\n", est_freq/1000000,
154	       (est_freq%1000000)*100/1000000);
 
 
155
156        cpu_khz = est_freq / 1000;
 
 
 
 
 
 
 
 
 
157
158	mips_scroll_message();
159#ifdef CONFIG_I8253		/* Only Malta has a PIT */
 
 
160	setup_pit_timer();
 
 
 
 
 
 
 
 
 
 
 
161#endif
162
163	plat_perf_setup();
164}
v3.15
  1/*
  2 * Carsten Langgaard, carstenl@mips.com
  3 * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
  4 *
  5 *  This program is free software; you can distribute it and/or modify it
  6 *  under the terms of the GNU General Public License (Version 2) as
  7 *  published by the Free Software Foundation.
  8 *
  9 *  This program is distributed in the hope it will be useful, but WITHOUT
 10 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12 *  for more details.
 13 *
 14 *  You should have received a copy of the GNU General Public License along
 15 *  with this program; if not, write to the Free Software Foundation, Inc.,
 16 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
 17 *
 18 * Setting up the clock on the MIPS boards.
 19 */
 
 20#include <linux/types.h>
 21#include <linux/i8253.h>
 22#include <linux/init.h>
 23#include <linux/kernel_stat.h>
 24#include <linux/sched.h>
 25#include <linux/spinlock.h>
 26#include <linux/interrupt.h>
 
 27#include <linux/timex.h>
 28#include <linux/mc146818rtc.h>
 29
 30#include <asm/cpu.h>
 31#include <asm/mipsregs.h>
 32#include <asm/mipsmtregs.h>
 33#include <asm/hardirq.h>
 34#include <asm/irq.h>
 35#include <asm/div64.h>
 36#include <asm/setup.h>
 37#include <asm/time.h>
 38#include <asm/mc146818-time.h>
 39#include <asm/msc01_ic.h>
 40#include <asm/gic.h>
 41
 42#include <asm/mips-boards/generic.h>
 
 
 43#include <asm/mips-boards/maltaint.h>
 44
 
 
 45static int mips_cpu_timer_irq;
 46static int mips_cpu_perf_irq;
 47extern int cp0_perfcount_irq;
 48
 49static void mips_timer_dispatch(void)
 50{
 51	do_IRQ(mips_cpu_timer_irq);
 52}
 53
 54static void mips_perf_dispatch(void)
 55{
 56	do_IRQ(mips_cpu_perf_irq);
 57}
 58
 59static unsigned int freqround(unsigned int freq, unsigned int amount)
 60{
 61	freq += amount;
 62	freq -= freq % (amount*2);
 63	return freq;
 64}
 65
 66/*
 67 * Estimate CPU and GIC frequencies.
 68 */
 69static void __init estimate_frequencies(void)
 70{
 
 
 
 71	unsigned long flags;
 72	unsigned int count, start;
 73#ifdef CONFIG_IRQ_GIC
 74	unsigned int giccount = 0, gicstart = 0;
 75#endif
 76
 77#if defined (CONFIG_KVM_GUEST) && defined (CONFIG_KVM_HOST_FREQ)
 78	unsigned int prid = read_c0_prid() & (PRID_COMP_MASK | PRID_IMP_MASK);
 79
 80	/*
 81	 * XXXKYMA: hardwire the CPU frequency to Host Freq/4
 82	 */
 83	count = (CONFIG_KVM_HOST_FREQ * 1000000) >> 3;
 84	if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) &&
 85	    (prid != (PRID_COMP_MIPS | PRID_IMP_25KF)))
 86		count *= 2;
 87
 88	mips_hpt_frequency = count;
 89	return;
 90#endif
 91
 92	local_irq_save(flags);
 93
 94	/* Start counter exactly on falling edge of update flag. */
 95	while (CMOS_READ(RTC_REG_A) & RTC_UIP);
 96	while (!(CMOS_READ(RTC_REG_A) & RTC_UIP));
 97
 98	/* Initialize counters. */
 99	start = read_c0_count();
100#ifdef CONFIG_IRQ_GIC
101	if (gic_present)
102		GICREAD(GIC_REG(SHARED, GIC_SH_COUNTER_31_00), gicstart);
103#endif
104
105	/* Read counter exactly on falling edge of update flag. */
106	while (CMOS_READ(RTC_REG_A) & RTC_UIP);
107	while (!(CMOS_READ(RTC_REG_A) & RTC_UIP));
108
109	count = read_c0_count();
110#ifdef CONFIG_IRQ_GIC
111	if (gic_present)
112		GICREAD(GIC_REG(SHARED, GIC_SH_COUNTER_31_00), giccount);
113#endif
114
 
115	local_irq_restore(flags);
116
117	count -= start;
118	mips_hpt_frequency = count;
 
 
 
 
 
 
119
120#ifdef CONFIG_IRQ_GIC
121	if (gic_present) {
122		giccount -= gicstart;
123		gic_frequency = giccount;
124	}
125#endif
126}
127
128void read_persistent_clock(struct timespec *ts)
129{
130	ts->tv_sec = mc146818_get_cmos_time();
131	ts->tv_nsec = 0;
132}
133
134static void __init plat_perf_setup(void)
135{
136#ifdef MSC01E_INT_BASE
137	if (cpu_has_veic) {
138		set_vi_handler(MSC01E_INT_PERFCTR, mips_perf_dispatch);
139		mips_cpu_perf_irq = MSC01E_INT_BASE + MSC01E_INT_PERFCTR;
140	} else
141#endif
142	if (cp0_perfcount_irq >= 0) {
143		if (cpu_has_vint)
144			set_vi_handler(cp0_perfcount_irq, mips_perf_dispatch);
145		mips_cpu_perf_irq = MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
146#ifdef CONFIG_SMP
147		irq_set_handler(mips_cpu_perf_irq, handle_percpu_irq);
148#endif
149	}
150}
151
152unsigned int get_c0_compare_int(void)
153{
154#ifdef MSC01E_INT_BASE
155	if (cpu_has_veic) {
156		set_vi_handler(MSC01E_INT_CPUCTR, mips_timer_dispatch);
157		mips_cpu_timer_irq = MSC01E_INT_BASE + MSC01E_INT_CPUCTR;
158	} else
159#endif
160	{
161		if (cpu_has_vint)
162			set_vi_handler(cp0_compare_irq, mips_timer_dispatch);
163		mips_cpu_timer_irq = MIPS_CPU_IRQ_BASE + cp0_compare_irq;
164	}
165
166	return mips_cpu_timer_irq;
167}
168
169static void __init init_rtc(void)
170{
171	/* stop the clock whilst setting it up */
172	CMOS_WRITE(RTC_SET | RTC_24H, RTC_CONTROL);
173
174	/* 32KHz time base */
175	CMOS_WRITE(RTC_REF_CLCK_32KHZ, RTC_FREQ_SELECT);
176
177	/* start the clock */
178	CMOS_WRITE(RTC_24H, RTC_CONTROL);
179}
180
181void __init plat_time_init(void)
182{
183	unsigned int prid = read_c0_prid() & (PRID_COMP_MASK | PRID_IMP_MASK);
184	unsigned int freq;
185
186	init_rtc();
187	estimate_frequencies();
188
189	freq = mips_hpt_frequency;
190	if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) &&
191	    (prid != (PRID_COMP_MIPS | PRID_IMP_25KF)))
192		freq *= 2;
193	freq = freqround(freq, 5000);
194	printk("CPU frequency %d.%02d MHz\n", freq/1000000,
195	       (freq%1000000)*100/1000000);
196
197	mips_scroll_message();
198
199#ifdef CONFIG_I8253
200	/* Only Malta has a PIT. */
201	setup_pit_timer();
202#endif
203
204#ifdef CONFIG_IRQ_GIC
205	if (gic_present) {
206		freq = freqround(gic_frequency, 5000);
207		printk("GIC frequency %d.%02d MHz\n", freq/1000000,
208		       (freq%1000000)*100/1000000);
209#ifdef CONFIG_CSRC_GIC
210		gic_clocksource_init(gic_frequency);
211#endif
212	}
213#endif
214
215	plat_perf_setup();
216}