release/src-rt/linux/linux-2.6/arch/mips/brcm-boards/bcm947xx/time.c

   1 /*
   2  * Copyright (C) 2008, Broadcom Corporation
   3  * All Rights Reserved.
   4  *
   5  * THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
   6  * KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
   7  * SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
   8  * FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
   9  *
  10  * $Id: time.c,v 1.9 2009/07/17 06:23:12 Exp $
  11  */
  12 #include <linux/config.h>
  13 #include <linux/init.h>
  14 #include <linux/kernel.h>
  15 #include <linux/sched.h>
  16 #include <linux/serial_reg.h>
  17 #include <linux/interrupt.h>
  18 #include <asm/addrspace.h>
  19 #include <asm/io.h>
  20 #include <asm/time.h>
  21
  22 #include <typedefs.h>
  23 #include <osl.h>
  24 #include <bcmutils.h>
  25 #include <bcmnvram.h>
  26 #include <hndsoc.h>
  27 #include <sbchipc.h>
  28 #include <siutils.h>
  29 #include <hndmips.h>
  30 #include <mipsinc.h>
  31 #include <hndcpu.h>
  32 #include <bcmdevs.h>
  33
  34 /* Global SB handle */
  35 extern si_t *bcm947xx_sih;
  36 extern spinlock_t bcm947xx_sih_lock;
  37
  38 /* Convenience */
  39 #define sih bcm947xx_sih
  40 #define sih_lock bcm947xx_sih_lock
  41
  42 #define WATCHDOG_MIN    3000    /* milliseconds */
  43 extern int panic_timeout;
  44 static int watchdog = 0;
  45
  46 #ifndef CONFIG_HWSIM
  47 static u8 *mcr = NULL;
  48 #endif /* CONFIG_HWSIM */
  49
  50 void __init
  51 bcm947xx_time_init(void)
  52 {
  53         unsigned int hz;
  54         char cn[8];
  55
  56         /*
  57          * Use deterministic values for initial counter interrupt
  58          * so that calibrate delay avoids encountering a counter wrap.
  59          */
  60         write_c0_count(0);
  61         write_c0_compare(0xffff);
  62
  63         if (!(hz = si_cpu_clock(sih)))
  64                 hz = 100000000;
  65
  66         bcm_chipname(sih->chip, cn, 8);
  67         printk("CPU: BCM%s rev %d pkg %d at %d MHz\n", cn, sih->chiprev, sih->chippkg,
  68                (hz + 500000) / 1000000);
  69
  70         /* Set MIPS counter frequency for fixed_rate_gettimeoffset() */
  71         if (sih->chip == BCM5354_CHIP_ID &&
  72                 strncmp(nvram_safe_get("hardware_version"), "WL520G", 6) == 0)
  73                 mips_hpt_frequency = 100000000; // Fix WL520GUGC clock
  74         else
  75                 mips_hpt_frequency = hz / 2;
  76
  77         /* Set watchdog interval in ms */
  78         watchdog = simple_strtoul(nvram_safe_get("watchdog"), NULL, 0);
  79
  80         /* Ensure at least WATCHDOG_MIN */
  81         if ((watchdog > 0) && (watchdog < WATCHDOG_MIN))
  82                 watchdog = WATCHDOG_MIN;
  83
  84         /* Set panic timeout in seconds */
  85         panic_timeout = watchdog / 1000;
  86 }
  87
  88 #ifdef CONFIG_HND_BMIPS3300_PROF
  89 extern bool hndprofiling;
  90 #ifdef CONFIG_MIPS64
  91 typedef u_int64_t sbprof_pc;
  92 #else
  93 typedef u_int32_t sbprof_pc;
  94 #endif
  95 extern void sbprof_cpu_intr(sbprof_pc restartpc);
  96 #endif  /* CONFIG_HND_BMIPS3300_PROF */
  97
  98 static irqreturn_t
  99 bcm947xx_timer_interrupt(int irq, void *dev_id)
 100 {
 101 #ifdef CONFIG_HND_BMIPS3300_PROF
 102         /*
 103          * Are there any ExcCode or other mean(s) to determine what has caused
 104          * the timer interrupt? For now simply stop the normal timer proc if
 105          * count register is less than compare register.
 106          */
 107         if (hndprofiling) {
 108                 sbprof_cpu_intr(read_c0_epc() +
 109                                 ((read_c0_cause() >> (CAUSEB_BD - 2)) & 4));
 110                 if (read_c0_count() < read_c0_compare())
 111                         return (IRQ_HANDLED);
 112         }
 113 #endif  /* CONFIG_HND_BMIPS3300_PROF */
 114
 115         /* Generic MIPS timer code */
 116         timer_interrupt(irq, dev_id);
 117
 118         /* Set the watchdog timer to reset after the specified number of ms */
 119         if (watchdog > 0) {
 120                 if (((si_t *)sih)->chip == BCM5354_CHIP_ID)
 121                         si_watchdog(sih, WATCHDOG_CLOCK_5354 / 1000 * watchdog);
 122                 else
 123                         si_watchdog_ms(sih, watchdog);
 124         }
 125
 126 #ifdef  CONFIG_HWSIM
 127         (*((int *)0xa0000f1c))++;
 128 #else
 129         /* Blink one of the LEDs in the external UART */
 130         if (mcr && !(jiffies % (HZ/2)))
 131                 writeb(readb(mcr) ^ UART_MCR_OUT2, mcr);
 132 #endif
 133
 134         return (IRQ_HANDLED);
 135 }
 136
 137 static struct irqaction bcm947xx_timer_irqaction = {
 138         bcm947xx_timer_interrupt,
 139         IRQF_DISABLED,
 140         { { 0 } },
 141         "timer",
 142         NULL,
 143         NULL,
 144         0,
 145         NULL
 146 };
 147
 148 void __init
 149 plat_timer_setup(struct irqaction *irq)
 150 {
 151         /* Enable the timer interrupt */
 152         setup_irq(7, &bcm947xx_timer_irqaction);
 153 }
 154
 155 #define CFE_UPDATE 1            // added by Chen-I for mac/regulation update
 156
 157 #ifdef CFE_UPDATE
 158 void bcm947xx_watchdog_disable(void)
 159 {
 160         watchdog=0;
 161         si_watchdog(sih, 0);
 162 }
 163 #endif
 164