1 /***************************************************************************/
4 * timers.c - Generic hardware timer support.
6 * Copyright (C) 1993 Hamish Macdonald
7 * Copyright (C) 1999 D. Jeff Dionne
8 * Copyright (C) 2001 Georges Menie, Ken Desmet
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
15 /***************************************************************************/
17 #include <linux/types.h>
18 #include <linux/kernel.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>
29 /***************************************************************************/
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
35 #define TICKS_PER_JIFFY 41450
37 #elif defined(CONFIG_XCOPILOT_BUGS)
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
44 #define CLOCK_SOURCE TCTL_CLKSOURCE_SYSCLK
46 #define TICKS_PER_JIFFY 0xd7e4
49 /* default to using the 32Khz clock */
50 #define CLOCK_SOURCE TCTL_CLKSOURCE_32KHZ
52 #define TICKS_PER_JIFFY 10
55 static u32 m68328_tick_cnt
;
56 static irq_handler_t timer_interrupt
;
58 /***************************************************************************/
60 static irqreturn_t
hw_tick(int irq
, void *dummy
)
65 m68328_tick_cnt
+= TICKS_PER_JIFFY
;
66 return timer_interrupt(irq
, dummy
);
69 /***************************************************************************/
71 static struct irqaction m68328_timer_irq
= {
73 .flags
= IRQF_DISABLED
| IRQF_TIMER
,
77 /***************************************************************************/
79 static cycle_t
m68328_read_clk(struct clocksource
*cs
)
84 local_irq_save(flags
);
85 cycles
= m68328_tick_cnt
+ TCN
;
86 local_irq_restore(flags
);
91 /***************************************************************************/
93 static struct clocksource m68328_clk
= {
96 .read
= m68328_read_clk
,
97 .mask
= CLOCKSOURCE_MASK(32),
98 .flags
= CLOCK_SOURCE_IS_CONTINUOUS
,
101 /***************************************************************************/
103 void hw_timer_init(irq_handler_t handler
)
105 /* disable timer 1 */
109 setup_irq(TMR_IRQ_NUM
, &m68328_timer_irq
);
111 /* Restart mode, Enable int, Set clock source */
112 TCTL
= TCTL_OM
| TCTL_IRQEN
| CLOCK_SOURCE
;
114 TCMP
= TICKS_PER_JIFFY
;
118 clocksource_register_hz(&m68328_clk
, TICKS_PER_JIFFY
*HZ
);
119 timer_interrupt
= handler
;
122 /***************************************************************************/
124 int m68328_hwclk(int set
, struct rtc_time
*t
)
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;
137 /***************************************************************************/