1 /* 2 * Copyright (C) 2000,2001,2004 Broadcom Corporation 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 2 7 * of the License, or (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 */ 14 #include <linux/clocksource.h> 15 #include <linux/sched_clock.h> 16 17 #include <asm/addrspace.h> 18 #include <asm/io.h> 19 #include <asm/time.h> 20 21 #include <asm/sibyte/bcm1480_regs.h> 22 #include <asm/sibyte/sb1250_regs.h> 23 #include <asm/sibyte/bcm1480_int.h> 24 #include <asm/sibyte/bcm1480_scd.h> 25 26 #include <asm/sibyte/sb1250.h> 27 28 static u64 bcm1480_hpt_read(struct clocksource *cs) 29 { 30 return (u64) __raw_readq(IOADDR(A_SCD_ZBBUS_CYCLE_COUNT)); 31 } 32 33 struct clocksource bcm1480_clocksource = { 34 .name = "zbbus-cycles", 35 .rating = 200, 36 .read = bcm1480_hpt_read, 37 .mask = CLOCKSOURCE_MASK(64), 38 .flags = CLOCK_SOURCE_IS_CONTINUOUS, 39 }; 40 41 static u64 notrace sb1480_read_sched_clock(void) 42 { 43 return __raw_readq(IOADDR(A_SCD_ZBBUS_CYCLE_COUNT)); 44 } 45 46 void __init sb1480_clocksource_init(void) 47 { 48 struct clocksource *cs = &bcm1480_clocksource; 49 unsigned int plldiv; 50 unsigned long zbbus; 51 52 plldiv = G_BCM1480_SYS_PLL_DIV(__raw_readq(IOADDR(A_SCD_SYSTEM_CFG))); 53 zbbus = ((plldiv >> 1) * 50000000) + ((plldiv & 1) * 25000000); 54 clocksource_register_hz(cs, zbbus); 55 56 sched_clock_register(sb1480_read_sched_clock, 64, zbbus); 57 } 58