1 // SPDX-License-Identifier: GPL-2.0-or-later 1
2 /*
3 * Copyright (C) 2000, 2001 Broadcom Corporati
4 */
5 #include <linux/clocksource.h>
6 #include <linux/sched_clock.h>
7
8 #include <asm/addrspace.h>
9 #include <asm/io.h>
10 #include <asm/time.h>
11
12 #include <asm/sibyte/sb1250.h>
13 #include <asm/sibyte/sb1250_regs.h>
14 #include <asm/sibyte/sb1250_int.h>
15 #include <asm/sibyte/sb1250_scd.h>
16
17 #define SB1250_HPT_NUM 3
18 #define SB1250_HPT_VALUE M_SCD_TIMER_CN
19
20 /*
21 * The HPT is free running from SB1250_HPT_VAL
22 * again.
23 */
24 static inline u64 sb1250_hpt_get_cycles(void)
25 {
26 unsigned int count;
27 void __iomem *addr;
28
29 addr = IOADDR(A_SCD_TIMER_REGISTER(SB1
30 count = G_SCD_TIMER_CNT(__raw_readq(ad
31
32 return SB1250_HPT_VALUE - count;
33 }
34
35 static u64 sb1250_hpt_read(struct clocksource
36 {
37 return sb1250_hpt_get_cycles();
38 }
39
40 struct clocksource bcm1250_clocksource = {
41 .name = "bcm1250-counter-3",
42 .rating = 200,
43 .read = sb1250_hpt_read,
44 .mask = CLOCKSOURCE_MASK(23),
45 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
46 };
47
48 static u64 notrace sb1250_read_sched_clock(voi
49 {
50 return sb1250_hpt_get_cycles();
51 }
52
53 void __init sb1250_clocksource_init(void)
54 {
55 struct clocksource *cs = &bcm1250_cloc
56
57 /* Setup hpt using timer #3 but do not
58 __raw_writeq(0,
59 IOADDR(A_SCD_TIMER_REGIST
60
61 __raw_writeq(SB1250_HPT_VALUE,
62 IOADDR(A_SCD_TIMER_REGIST
63
64 __raw_writeq(M_SCD_TIMER_ENABLE | M_SC
65 IOADDR(A_SCD_TIMER_REGIST
66
67
68 clocksource_register_hz(cs, V_SCD_TIME
69
70 sched_clock_register(sb1250_read_sched
71 }
72
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.