1 // SPDX-License-Identifier: GPL-2.0-only << 2 /* 1 /* 3 * Carsten Langgaard, carstenl@mips.com 2 * Carsten Langgaard, carstenl@mips.com 4 * Copyright (C) 1999,2000 MIPS Technologies, 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. 5 * 17 * 6 * Setting up the clock on the MIPS boards. 18 * Setting up the clock on the MIPS boards. 7 */ 19 */ 8 20 9 #include <linux/init.h> 21 #include <linux/init.h> 10 #include <linux/kernel_stat.h> 22 #include <linux/kernel_stat.h> 11 #include <linux/ptrace.h> 23 #include <linux/ptrace.h> 12 #include <linux/sched.h> 24 #include <linux/sched.h> 13 #include <linux/spinlock.h> 25 #include <linux/spinlock.h> 14 #include <linux/mc146818rtc.h> 26 #include <linux/mc146818rtc.h> 15 #include <linux/irq.h> 27 #include <linux/irq.h> 16 #include <linux/timex.h> 28 #include <linux/timex.h> 17 29 18 #include <asm/mipsregs.h> 30 #include <asm/mipsregs.h> 19 #include <asm/time.h> 31 #include <asm/time.h> 20 #include <asm/mach-rc32434/rc32434.h> 32 #include <asm/mach-rc32434/rc32434.h> 21 33 22 extern unsigned int idt_cpu_freq; 34 extern unsigned int idt_cpu_freq; 23 35 24 /* 36 /* 25 * Figure out the r4k offset, the amount to in 37 * Figure out the r4k offset, the amount to increment the compare 26 * register for each time tick. There is no RT 38 * register for each time tick. There is no RTC available. 27 * 39 * 28 * The RC32434 counts at half the CPU *core* s 40 * The RC32434 counts at half the CPU *core* speed. 29 */ 41 */ 30 static unsigned long __init cal_r4koff(void) 42 static unsigned long __init cal_r4koff(void) 31 { 43 { 32 mips_hpt_frequency = idt_cpu_freq * ID 44 mips_hpt_frequency = idt_cpu_freq * IDT_CLOCK_MULT / 2; 33 45 34 return mips_hpt_frequency / HZ; 46 return mips_hpt_frequency / HZ; 35 } 47 } 36 48 37 void __init plat_time_init(void) 49 void __init plat_time_init(void) 38 { 50 { 39 unsigned int est_freq; 51 unsigned int est_freq; 40 unsigned long flags, r4k_offset; 52 unsigned long flags, r4k_offset; 41 53 42 local_irq_save(flags); 54 local_irq_save(flags); 43 55 44 printk(KERN_INFO "calculating r4koff.. 56 printk(KERN_INFO "calculating r4koff... "); 45 r4k_offset = cal_r4koff(); 57 r4k_offset = cal_r4koff(); 46 printk("%08lx(%d)\n", r4k_offset, (int 58 printk("%08lx(%d)\n", r4k_offset, (int) r4k_offset); 47 59 48 est_freq = 2 * r4k_offset * HZ; 60 est_freq = 2 * r4k_offset * HZ; 49 est_freq += 5000; /* round */ 61 est_freq += 5000; /* round */ 50 est_freq -= est_freq % 10000; 62 est_freq -= est_freq % 10000; 51 printk(KERN_INFO "CPU frequency %d.%02 63 printk(KERN_INFO "CPU frequency %d.%02d MHz\n", est_freq / 1000000, 52 (est_freq % 1000000) * 100 / 10 64 (est_freq % 1000000) * 100 / 1000000); 53 local_irq_restore(flags); 65 local_irq_restore(flags); 54 } 66 } 55 67
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