1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2000,2001,2004 Broadcom Corporation
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/bcm1480_regs.h>
13#include <asm/sibyte/sb1250_regs.h>
14#include <asm/sibyte/bcm1480_int.h>
15#include <asm/sibyte/bcm1480_scd.h>
16
17#include <asm/sibyte/sb1250.h>
18
19static u64 bcm1480_hpt_read(struct clocksource *cs)
20{
21 return (u64) __raw_readq(IOADDR(A_SCD_ZBBUS_CYCLE_COUNT));
22}
23
24struct clocksource bcm1480_clocksource = {
25 .name = "zbbus-cycles",
26 .rating = 200,
27 .read = bcm1480_hpt_read,
28 .mask = CLOCKSOURCE_MASK(64),
29 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
30};
31
32static u64 notrace sb1480_read_sched_clock(void)
33{
34 return __raw_readq(addr: IOADDR(A_SCD_ZBBUS_CYCLE_COUNT));
35}
36
37void __init sb1480_clocksource_init(void)
38{
39 struct clocksource *cs = &bcm1480_clocksource;
40 unsigned int plldiv;
41 unsigned long zbbus;
42
43 plldiv = G_BCM1480_SYS_PLL_DIV(__raw_readq(addr: IOADDR(A_SCD_SYSTEM_CFG)));
44 zbbus = ((plldiv >> 1) * 50000000) + ((plldiv & 1) * 25000000);
45 clocksource_register_hz(cs, hz: zbbus);
46
47 sched_clock_register(read: sb1480_read_sched_clock, bits: 64, rate: zbbus);
48}
49

source code of linux/arch/mips/kernel/csrc-bcm1480.c