1/***************************************************************************/ 2 3/* 4 * timers.c - Generic hardware timer support. 5 * 6 * Copyright (C) 1993 Hamish Macdonald 7 * Copyright (C) 1999 D. Jeff Dionne 8 * Copyright (C) 2001 Georges Menie, Ken Desmet 9 * 10 * This file is subject to the terms and conditions of the GNU General Public 11 * License. See the file COPYING in the main directory of this archive 12 * for more details. 13 */ 14 15/***************************************************************************/ 16 17#include <linux/types.h> 18#include <linux/kernel.h> 19#include <linux/mm.h> 20#include <linux/interrupt.h> 21#include <linux/irq.h> 22#include <linux/clocksource.h> 23#include <linux/rtc.h> 24#include <asm/setup.h> 25#include <asm/pgtable.h> 26#include <asm/machdep.h> 27#include <asm/MC68VZ328.h> 28 29/***************************************************************************/ 30 31#if defined(CONFIG_DRAGEN2) 32/* with a 33.16 MHz clock, this will give usec resolution to the time functions */ 33#define CLOCK_SOURCE TCTL_CLKSOURCE_SYSCLK 34#define CLOCK_PRE 7 35#define TICKS_PER_JIFFY 41450 36 37#elif defined(CONFIG_XCOPILOT_BUGS) 38/* 39 * The only thing I know is that CLK32 is not available on Xcopilot 40 * I have little idea about what frequency SYSCLK has on Xcopilot. 41 * The values for prescaler and compare registers were simply 42 * taken from the original source 43 */ 44#define CLOCK_SOURCE TCTL_CLKSOURCE_SYSCLK 45#define CLOCK_PRE 2 46#define TICKS_PER_JIFFY 0xd7e4 47 48#else 49/* default to using the 32Khz clock */ 50#define CLOCK_SOURCE TCTL_CLKSOURCE_32KHZ 51#define CLOCK_PRE 31 52#define TICKS_PER_JIFFY 10 53#endif 54 55static u32 m68328_tick_cnt; 56static irq_handler_t timer_interrupt; 57 58/***************************************************************************/ 59 60static irqreturn_t hw_tick(int irq, void *dummy) 61{ 62 /* Reset Timer1 */ 63 TSTAT &= 0; 64 65 m68328_tick_cnt += TICKS_PER_JIFFY; 66 return timer_interrupt(irq, dummy); 67} 68 69/***************************************************************************/ 70 71static struct irqaction m68328_timer_irq = { 72 .name = "timer", 73 .flags = IRQF_TIMER, 74 .handler = hw_tick, 75}; 76 77/***************************************************************************/ 78 79static cycle_t m68328_read_clk(struct clocksource *cs) 80{ 81 unsigned long flags; 82 u32 cycles; 83 84 local_irq_save(flags); 85 cycles = m68328_tick_cnt + TCN; 86 local_irq_restore(flags); 87 88 return cycles; 89} 90 91/***************************************************************************/ 92 93static struct clocksource m68328_clk = { 94 .name = "timer", 95 .rating = 250, 96 .read = m68328_read_clk, 97 .mask = CLOCKSOURCE_MASK(32), 98 .flags = CLOCK_SOURCE_IS_CONTINUOUS, 99}; 100 101/***************************************************************************/ 102 103void hw_timer_init(irq_handler_t handler) 104{ 105 /* disable timer 1 */ 106 TCTL = 0; 107 108 /* set ISR */ 109 setup_irq(TMR_IRQ_NUM, &m68328_timer_irq); 110 111 /* Restart mode, Enable int, Set clock source */ 112 TCTL = TCTL_OM | TCTL_IRQEN | CLOCK_SOURCE; 113 TPRER = CLOCK_PRE; 114 TCMP = TICKS_PER_JIFFY; 115 116 /* Enable timer 1 */ 117 TCTL |= TCTL_TEN; 118 clocksource_register_hz(&m68328_clk, TICKS_PER_JIFFY*HZ); 119 timer_interrupt = handler; 120} 121 122/***************************************************************************/ 123 124int m68328_hwclk(int set, struct rtc_time *t) 125{ 126 if (!set) { 127 long now = RTCTIME; 128 t->tm_year = t->tm_mon = t->tm_mday = 1; 129 t->tm_hour = (now >> 24) % 24; 130 t->tm_min = (now >> 16) % 60; 131 t->tm_sec = now % 60; 132 } 133 134 return 0; 135} 136 137/***************************************************************************/ 138