1 /* ASB2303-specific timer specifications
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
11 #ifndef _ASM_UNIT_TIMEX_H
12 #define _ASM_UNIT_TIMEX_H
15 #include <linux/irq.h>
16 #endif /* __ASSEMBLY__ */
18 #include <asm/timer-regs.h>
19 #include <unit/clock.h>
20 #include <asm/param.h>
23 * jiffies counter specifications
26 #define TMJCBR_MAX 0xffff
31 #define TMJCIRQ TM1IRQ
32 #define TMJCICR TM1ICR
36 #define MN10300_SRC_IOCLK MN10300_IOCLK
39 # error HZ undeclared.
41 /* use as little prescaling as possible to avoid losing accuracy */
42 #if (MN10300_SRC_IOCLK + HZ / 2) / HZ - 1 <= TMJCBR_MAX
43 # define IOCLK_PRESCALE 1
44 # define JC_TIMER_CLKSRC TM0MD_SRC_IOCLK
45 # define TSC_TIMER_CLKSRC TM4MD_SRC_IOCLK
46 #elif (MN10300_SRC_IOCLK / 8 + HZ / 2) / HZ - 1 <= TMJCBR_MAX
47 # define IOCLK_PRESCALE 8
48 # define JC_TIMER_CLKSRC TM0MD_SRC_IOCLK_8
49 # define TSC_TIMER_CLKSRC TM4MD_SRC_IOCLK_8
50 #elif (MN10300_SRC_IOCLK / 32 + HZ / 2) / HZ - 1 <= TMJCBR_MAX
51 # define IOCLK_PRESCALE 32
52 # define JC_TIMER_CLKSRC TM0MD_SRC_IOCLK_32
53 # define TSC_TIMER_CLKSRC TM4MD_SRC_IOCLK_32
58 #define MN10300_JCCLK (MN10300_SRC_IOCLK / IOCLK_PRESCALE)
59 #define MN10300_TSCCLK (MN10300_SRC_IOCLK / IOCLK_PRESCALE)
61 #define MN10300_JC_PER_HZ ((MN10300_JCCLK + HZ / 2) / HZ)
62 #define MN10300_TSC_PER_HZ ((MN10300_TSCCLK + HZ / 2) / HZ)
64 static inline void startup_jiffies_counter(void)
69 TMJCBR = MN10300_JC_PER_HZ - 1;
74 TM1MD_SRC_TM0CASCADE << 8 |
76 TM1MD_INIT_COUNTER << 8;
80 TM1MD_SRC_TM0CASCADE << 8 |
82 TM1MD_COUNT_ENABLE << 8;
86 TMJCICR |= GxICR_ENABLE | GxICR_DETECT | GxICR_REQUEST;
90 static inline void shutdown_jiffies_counter(void)
94 #endif /* !__ASSEMBLY__ */
98 * timestamp counter specifications
101 #define TMTSCBR_MAX 0xffffffff
102 #define TMTSCBC TM45BC
106 static inline void startup_timestamp_counter(void)
110 /* set up timer 4 & 5 cascaded as a 32-bit counter to count real time
111 * - count down from 4Gig-1 to 0 and wrap at IOCLK rate
113 TM45BR = TMTSCBR_MAX;
116 TM4MD = TSC_TIMER_CLKSRC;
117 TM4MD |= TM4MD_INIT_COUNTER;
118 TM4MD &= ~TM4MD_INIT_COUNTER;
122 TM5MD = TM5MD_SRC_TM4CASCADE;
123 TM5MD |= TM5MD_INIT_COUNTER;
124 TM5MD &= ~TM5MD_INIT_COUNTER;
128 TM5MD |= TM5MD_COUNT_ENABLE;
129 TM4MD |= TM4MD_COUNT_ENABLE;
134 static inline void shutdown_timestamp_counter(void)
144 * we use a cascaded pair of 16-bit down-counting timers to count I/O
145 * clock cycles for the purposes of time keeping
147 typedef unsigned long cycles_t;
149 static inline cycles_t read_timestamp_counter(void)
151 return (cycles_t)TMTSCBC;
154 #endif /* !__ASSEMBLY__ */
156 #endif /* _ASM_UNIT_TIMEX_H */