LXR linux/arch/mips/pmcs-msp71xx/msp

   1/*
   2 * Setting up the clock on MSP SOCs.  No RTC typically.
   3 *
   4 * Carsten Langgaard, carstenl@mips.com
   5 * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
   6 *
   7 * ########################################################################
   8 *
   9 *  This program is free software; you can distribute it and/or modify it
  10 *  under the terms of the GNU General Public License (Version 2) as
  11 *  published by the Free Software Foundation.
  12 *
  13 *  This program is distributed in the hope it will be useful, but WITHOUT
  14 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 *  for more details.
  17 *
  18 *  You should have received a copy of the GNU General Public License along
  19 *  with this program; if not, write to the Free Software Foundation, Inc.,
  20 *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  21 *
  22 * ########################################################################
  23 */
  24
  25#include <linux/init.h>
  26#include <linux/kernel_stat.h>
  27#include <linux/sched.h>
  28#include <linux/spinlock.h>
  29#include <linux/module.h>
  30#include <linux/ptrace.h>
  31
  32#include <asm/cevt-r4k.h>
  33#include <asm/mipsregs.h>
  34#include <asm/time.h>
  35
  36#include <msp_prom.h>
  37#include <msp_int.h>
  38#include <msp_regs.h>
  39
  40#define get_current_vpe()   \
  41        ((read_c0_tcbind() >> TCBIND_CURVPE_SHIFT) & TCBIND_CURVPE)
  42
  43static struct irqaction timer_vpe1;
  44static int tim_installed;
  45
  46void __init plat_time_init(void)
  47{
  48        char    *endp, *s;
  49        unsigned long cpu_rate = 0;
  50
  51        if (cpu_rate == 0) {
  52                s = prom_getenv("clkfreqhz");
  53                cpu_rate = simple_strtoul(s, &endp, 10);
  54                if (endp != NULL && *endp != 0) {
  55                        printk(KERN_ERR
  56                                "Clock rate in Hz parse error: %s\n", s);
  57                        cpu_rate = 0;
  58                }
  59        }
  60
  61        if (cpu_rate == 0) {
  62                s = prom_getenv("clkfreq");
  63                cpu_rate = 1000 * simple_strtoul(s, &endp, 10);
  64                if (endp != NULL && *endp != 0) {
  65                        printk(KERN_ERR
  66                                "Clock rate in MHz parse error: %s\n", s);
  67                        cpu_rate = 0;
  68                }
  69        }
  70
  71        if (cpu_rate == 0) {
  72#if defined(CONFIG_PMC_MSP7120_EVAL) \
  73 || defined(CONFIG_PMC_MSP7120_GW)
  74                cpu_rate = 400000000;
  75#elif defined(CONFIG_PMC_MSP7120_FPGA)
  76                cpu_rate = 25000000;
  77#else
  78                cpu_rate = 150000000;
  79#endif
  80                printk(KERN_ERR
  81                        "Failed to determine CPU clock rate, "
  82                        "assuming %ld hz ...\n", cpu_rate);
  83        }
  84
  85        printk(KERN_WARNING "Clock rate set to %ld\n", cpu_rate);
  86
  87        /* timer frequency is 1/2 clock rate */
  88        mips_hpt_frequency = cpu_rate/2;
  89}
  90
  91unsigned int __cpuinit get_c0_compare_int(void)
  92{
  93        /* MIPS_MT modes may want timer for second VPE */
  94        if ((get_current_vpe()) && !tim_installed) {
  95                memcpy(&timer_vpe1, &c0_compare_irqaction, sizeof(timer_vpe1));
  96                setup_irq(MSP_INT_VPE1_TIMER, &timer_vpe1);
  97                tim_installed++;
  98        }
  99
 100        return get_current_vpe() ? MSP_INT_VPE1_TIMER : MSP_INT_VPE0_TIMER;
 101}
 102