Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * "High Precision Event Timer" based timekeeping. |
| 3 | * |
| 4 | * Copyright (c) 1991,1992,1995 Linus Torvalds |
| 5 | * Copyright (c) 1994 Alan Modra |
| 6 | * Copyright (c) 1995 Markus Kuhn |
| 7 | * Copyright (c) 1996 Ingo Molnar |
| 8 | * Copyright (c) 1998 Andrea Arcangeli |
Vojtech Pavlik | 2f82bde4 | 2006-06-26 13:58:38 +0200 | [diff] [blame] | 9 | * Copyright (c) 2002,2006 Vojtech Pavlik |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | * Copyright (c) 2003 Andi Kleen |
| 11 | * RTC support code taken from arch/i386/kernel/timers/time_hpet.c |
| 12 | */ |
| 13 | |
Thomas Gleixner | b8ce335 | 2007-10-12 23:04:07 +0200 | [diff] [blame] | 14 | #include <linux/clockchips.h> |
Thomas Gleixner | 081e10b | 2008-01-30 13:30:27 +0100 | [diff] [blame] | 15 | #include <linux/init.h> |
| 16 | #include <linux/interrupt.h> |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/time.h> |
Glauber Costa | 33c053d | 2008-07-21 18:42:52 -0300 | [diff] [blame] | 19 | #include <linux/mca.h> |
Jaswinder Singh Rajput | fe33118 | 2009-01-04 16:28:22 +0530 | [diff] [blame] | 20 | #include <linux/nmi.h> |
Thomas Gleixner | b8ce335 | 2007-10-12 23:04:07 +0200 | [diff] [blame] | 21 | |
Thomas Gleixner | 28318da | 2007-07-21 17:11:18 +0200 | [diff] [blame] | 22 | #include <asm/i8253.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <asm/hpet.h> |
Andi Kleen | 2aae950 | 2007-07-21 17:10:01 +0200 | [diff] [blame] | 24 | #include <asm/vgtod.h> |
Glauber de Oliveira Costa | ee238e5 | 2008-01-30 13:31:10 +0100 | [diff] [blame] | 25 | #include <asm/time.h> |
| 26 | #include <asm/timer.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | unsigned long profile_pc(struct pt_regs *regs) |
| 31 | { |
| 32 | unsigned long pc = instruction_pointer(regs); |
| 33 | |
Andi Kleen | 31679f3 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 34 | /* Assume the lock function has either no stack frame or a copy |
H. Peter Anvin | 65ea5b0 | 2008-01-30 13:30:56 +0100 | [diff] [blame] | 35 | of flags from PUSHF |
Andi Kleen | 31679f3 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 36 | Eflags always has bits 22 and up cleared unlike kernel addresses. */ |
Glauber Costa | 8de0b8a | 2008-07-11 14:10:13 -0300 | [diff] [blame] | 37 | if (!user_mode_vm(regs) && in_lock_functions(pc)) { |
Glauber Costa | 3927fa9 | 2008-07-11 13:53:43 -0300 | [diff] [blame] | 38 | #ifdef CONFIG_FRAME_POINTER |
| 39 | return *(unsigned long *)(regs->bp + sizeof(long)); |
| 40 | #else |
H. Peter Anvin | 65ea5b0 | 2008-01-30 13:30:56 +0100 | [diff] [blame] | 41 | unsigned long *sp = (unsigned long *)regs->sp; |
Andi Kleen | 31679f3 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 42 | if (sp[0] >> 22) |
| 43 | return sp[0]; |
| 44 | if (sp[1] >> 22) |
| 45 | return sp[1]; |
Glauber Costa | 3927fa9 | 2008-07-11 13:53:43 -0300 | [diff] [blame] | 46 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | } |
| 48 | return pc; |
| 49 | } |
| 50 | EXPORT_SYMBOL(profile_pc); |
| 51 | |
Jaswinder Singh | 57a3750 | 2008-12-17 23:17:21 +0530 | [diff] [blame] | 52 | static irqreturn_t timer_interrupt(int irq, void *dev_id) |
Thomas Gleixner | b8ce335 | 2007-10-12 23:04:07 +0200 | [diff] [blame] | 53 | { |
Hiroshi Shimamoto | 8ae9366 | 2008-12-12 15:52:26 -0800 | [diff] [blame] | 54 | inc_irq_stat(irq0_irqs); |
Thomas Gleixner | 4e77ae3 | 2007-10-12 23:04:07 +0200 | [diff] [blame] | 55 | |
Thomas Gleixner | b8ce335 | 2007-10-12 23:04:07 +0200 | [diff] [blame] | 56 | global_clock_event->event_handler(global_clock_event); |
| 57 | |
Glauber Costa | 33c053d | 2008-07-21 18:42:52 -0300 | [diff] [blame] | 58 | #ifdef CONFIG_MCA |
| 59 | if (MCA_bus) { |
| 60 | u8 irq_v = inb_p(0x61); /* read the current state */ |
| 61 | outb_p(irq_v|0x80, 0x61); /* reset the IRQ */ |
| 62 | } |
| 63 | #endif |
| 64 | |
Thomas Gleixner | b8ce335 | 2007-10-12 23:04:07 +0200 | [diff] [blame] | 65 | return IRQ_HANDLED; |
| 66 | } |
| 67 | |
Joerg Roedel | 6b37f5a | 2007-05-02 19:27:06 +0200 | [diff] [blame] | 68 | /* calibrate_cpu is used on systems with fixed rate TSCs to determine |
| 69 | * processor frequency */ |
| 70 | #define TICK_COUNT 100000000 |
Alok Kataria | 8fbbc4b | 2008-07-01 11:43:34 -0700 | [diff] [blame] | 71 | unsigned long __init calibrate_cpu(void) |
Joerg Roedel | 6b37f5a | 2007-05-02 19:27:06 +0200 | [diff] [blame] | 72 | { |
Thomas Gleixner | 2618f86 | 2007-07-21 17:10:18 +0200 | [diff] [blame] | 73 | int tsc_start, tsc_now; |
| 74 | int i, no_ctr_free; |
| 75 | unsigned long evntsel3 = 0, pmc3 = 0, pmc_now = 0; |
| 76 | unsigned long flags; |
Joerg Roedel | 6b37f5a | 2007-05-02 19:27:06 +0200 | [diff] [blame] | 77 | |
Thomas Gleixner | 2618f86 | 2007-07-21 17:10:18 +0200 | [diff] [blame] | 78 | for (i = 0; i < 4; i++) |
| 79 | if (avail_to_resrv_perfctr_nmi_bit(i)) |
| 80 | break; |
| 81 | no_ctr_free = (i == 4); |
| 82 | if (no_ctr_free) { |
Prarit Bhargava | 8652cb4 | 2008-11-12 13:35:00 -0500 | [diff] [blame] | 83 | WARN(1, KERN_WARNING "Warning: AMD perfctrs busy ... " |
| 84 | "cpu_khz value may be incorrect.\n"); |
Thomas Gleixner | 2618f86 | 2007-07-21 17:10:18 +0200 | [diff] [blame] | 85 | i = 3; |
| 86 | rdmsrl(MSR_K7_EVNTSEL3, evntsel3); |
| 87 | wrmsrl(MSR_K7_EVNTSEL3, 0); |
| 88 | rdmsrl(MSR_K7_PERFCTR3, pmc3); |
| 89 | } else { |
| 90 | reserve_perfctr_nmi(MSR_K7_PERFCTR0 + i); |
| 91 | reserve_evntsel_nmi(MSR_K7_EVNTSEL0 + i); |
| 92 | } |
| 93 | local_irq_save(flags); |
Li Zefan | 3eb0567 | 2008-02-08 04:19:25 -0800 | [diff] [blame] | 94 | /* start measuring cycles, incrementing from 0 */ |
Thomas Gleixner | 2618f86 | 2007-07-21 17:10:18 +0200 | [diff] [blame] | 95 | wrmsrl(MSR_K7_PERFCTR0 + i, 0); |
| 96 | wrmsrl(MSR_K7_EVNTSEL0 + i, 1 << 22 | 3 << 16 | 0x76); |
| 97 | rdtscl(tsc_start); |
| 98 | do { |
| 99 | rdmsrl(MSR_K7_PERFCTR0 + i, pmc_now); |
Andi Kleen | 6d63de8 | 2008-01-30 13:32:39 +0100 | [diff] [blame] | 100 | tsc_now = get_cycles(); |
Thomas Gleixner | 2618f86 | 2007-07-21 17:10:18 +0200 | [diff] [blame] | 101 | } while ((tsc_now - tsc_start) < TICK_COUNT); |
Joerg Roedel | 6b37f5a | 2007-05-02 19:27:06 +0200 | [diff] [blame] | 102 | |
Thomas Gleixner | 2618f86 | 2007-07-21 17:10:18 +0200 | [diff] [blame] | 103 | local_irq_restore(flags); |
| 104 | if (no_ctr_free) { |
| 105 | wrmsrl(MSR_K7_EVNTSEL3, 0); |
| 106 | wrmsrl(MSR_K7_PERFCTR3, pmc3); |
| 107 | wrmsrl(MSR_K7_EVNTSEL3, evntsel3); |
| 108 | } else { |
| 109 | release_perfctr_nmi(MSR_K7_PERFCTR0 + i); |
| 110 | release_evntsel_nmi(MSR_K7_EVNTSEL0 + i); |
| 111 | } |
Joerg Roedel | 6b37f5a | 2007-05-02 19:27:06 +0200 | [diff] [blame] | 112 | |
Thomas Gleixner | 2618f86 | 2007-07-21 17:10:18 +0200 | [diff] [blame] | 113 | return pmc_now * tsc_khz / (tsc_now - tsc_start); |
Joerg Roedel | 6b37f5a | 2007-05-02 19:27:06 +0200 | [diff] [blame] | 114 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 115 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | static struct irqaction irq0 = { |
Glauber Costa | 461ebd1 | 2008-07-11 15:25:13 -0300 | [diff] [blame] | 117 | .handler = timer_interrupt, |
Linus Torvalds | 936577c | 2009-02-22 10:27:49 -0800 | [diff] [blame] | 118 | .flags = IRQF_DISABLED | IRQF_IRQPOLL | IRQF_NOBALANCING | IRQF_TIMER, |
Thomas Gleixner | 2618f86 | 2007-07-21 17:10:18 +0200 | [diff] [blame] | 119 | .name = "timer" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | }; |
| 121 | |
Glauber de Oliveira Costa | ee238e5 | 2008-01-30 13:31:10 +0100 | [diff] [blame] | 122 | void __init hpet_time_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | { |
Thomas Gleixner | b8ce335 | 2007-10-12 23:04:07 +0200 | [diff] [blame] | 124 | if (!hpet_enable()) |
| 125 | setup_pit_timer(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | |
Thomas Gleixner | b8ce335 | 2007-10-12 23:04:07 +0200 | [diff] [blame] | 127 | setup_irq(0, &irq0); |
Glauber de Oliveira Costa | ee238e5 | 2008-01-30 13:31:10 +0100 | [diff] [blame] | 128 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 129 | |
Glauber de Oliveira Costa | ee238e5 | 2008-01-30 13:31:10 +0100 | [diff] [blame] | 130 | void __init time_init(void) |
| 131 | { |
Alok Kataria | 8fbbc4b | 2008-07-01 11:43:34 -0700 | [diff] [blame] | 132 | tsc_init(); |
Vojtech Pavlik | c08c820 | 2006-09-26 10:52:28 +0200 | [diff] [blame] | 133 | |
Glauber de Oliveira Costa | ee238e5 | 2008-01-30 13:31:10 +0100 | [diff] [blame] | 134 | late_time_init = choose_time_init(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | } |