1 /* $Id: timer.h,v 1.21 1999/04/20 13:22:51 anton Exp $
2  * timer.h:  Definitions for the timer chips on the Sparc.
3  *
4  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
5  */
6 
7 #include <linux/config.h>
8 
9 #ifndef _SPARC_TIMER_H
10 #define _SPARC_TIMER_H
11 
12 #include <asm/system.h>  /* For SUN4M_NCPUS */
13 #include <asm/sun4paddr.h>
14 #include <asm/btfixup.h>
15 
16 /* Timer structures. The interrupt timer has two properties which
17  * are the counter (which is handled in do_timer in sched.c) and the limit.
18  * This limit is where the timer's counter 'wraps' around. Oddly enough,
19  * the sun4c timer when it hits the limit wraps back to 1 and not zero
20  * thus when calculating the value at which it will fire a microsecond you
21  * must adjust by one.  Thanks SUN for designing such great hardware ;(
22  */
23 
24 /* Note that I am only going to use the timer that interrupts at
25  * Sparc IRQ 10.  There is another one available that can fire at
26  * IRQ 14. Currently it is left untouched, we keep the PROM's limit
27  * register value and let the prom take these interrupts.  This allows
28  * L1-A to work.
29  */
30 
31 struct sun4c_timer_info {
32   __volatile__ unsigned int cur_count10;
33   __volatile__ unsigned int timer_limit10;
34   __volatile__ unsigned int cur_count14;
35   __volatile__ unsigned int timer_limit14;
36 };
37 
38 #define SUN4C_TIMER_PHYSADDR   0xf3000000
39 #ifdef CONFIG_SUN4
40 #define SUN_TIMER_PHYSADDR SUN4_300_TIMER_PHYSADDR
41 #else
42 #define SUN_TIMER_PHYSADDR SUN4C_TIMER_PHYSADDR
43 #endif
44 
45 /* A sun4m has two blocks of registers which are probably of the same
46  * structure. LSI Logic's L64851 is told to _decrement_ from the limit
47  * value. Aurora behaves similarly but its limit value is compacted in
48  * other fashion (it's wider). Documented fields are defined here.
49  */
50 
51 /* As with the interrupt register, we have two classes of timer registers
52  * which are per-cpu and master.  Per-cpu timers only hit that cpu and are
53  * only level 14 ticks, master timer hits all cpus and is level 10.
54  */
55 
56 #define SUN4M_PRM_CNT_L       0x80000000
57 #define SUN4M_PRM_CNT_LVALUE  0x7FFFFC00
58 
59 struct sun4m_timer_percpu_info {
60   __volatile__ unsigned int l14_timer_limit;    /* Initial value is 0x009c4000 */
61   __volatile__ unsigned int l14_cur_count;
62 
63   /* This register appears to be write only and/or inaccessible
64    * on Uni-Processor sun4m machines.
65    */
66   __volatile__ unsigned int l14_limit_noclear;  /* Data access error is here */
67 
68   __volatile__ unsigned int cntrl;            /* =1 after POST on Aurora */
69   __volatile__ unsigned char space[PAGE_SIZE - 16];
70 };
71 
72 struct sun4m_timer_regs {
73 	struct sun4m_timer_percpu_info cpu_timers[SUN4M_NCPUS];
74 	volatile unsigned int l10_timer_limit;
75 	volatile unsigned int l10_cur_count;
76 
77 	/* Again, this appears to be write only and/or inaccessible
78 	 * on uni-processor sun4m machines.
79 	 */
80 	volatile unsigned int l10_limit_noclear;
81 
82 	/* This register too, it must be magic. */
83 	volatile unsigned int foobar;
84 
85 	volatile unsigned int cfg;     /* equals zero at boot time... */
86 };
87 
88 extern struct sun4m_timer_regs *sun4m_timers;
89 
90 #define SUN4D_PRM_CNT_L       0x80000000
91 #define SUN4D_PRM_CNT_LVALUE  0x7FFFFC00
92 
93 struct sun4d_timer_regs {
94 	volatile unsigned int l10_timer_limit;
95 	volatile unsigned int l10_cur_countx;
96 	volatile unsigned int l10_limit_noclear;
97 	volatile unsigned int ctrl;
98 	volatile unsigned int l10_cur_count;
99 };
100 
101 extern struct sun4d_timer_regs *sun4d_timers;
102 
103 extern __volatile__ unsigned int *master_l10_counter;
104 extern __volatile__ unsigned int *master_l10_limit;
105 
106 /* FIXME: Make do_[gs]ettimeofday btfixup calls */
107 BTFIXUPDEF_CALL(void, bus_do_settimeofday, struct timeval *tv)
108 #define bus_do_settimeofday(tv) BTFIXUP_CALL(bus_do_settimeofday)(tv)
109 
110 #endif /* !(_SPARC_TIMER_H) */
111