| | 1 | /* |
| | 2 | * Copyright 2001 MontaVista Software Inc. |
| | 3 | * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net |
| | 4 | * Copyright (c) 2003, 2004 Maciej W. Rozycki |
| | 5 | * |
| | 6 | * Common time service routines for MIPS machines. |
| | 7 | * |
| | 8 | * This program is free software; you can redistribute it and/or modify it |
| | 9 | * under the terms of the GNU General Public License as published by the |
| | 10 | * Free Software Foundation; either version 2 of the License, or (at your |
| | 11 | * option) any later version. |
| | 12 | */ |
| | 13 | #include <linux/bug.h> |
| | 14 | #include <linux/clockchips.h> |
| | 15 | #include <linux/types.h> |
| | 16 | #include <linux/kernel.h> |
| | 17 | #include <linux/init.h> |
| | 18 | #include <linux/sched.h> |
| | 19 | #include <linux/param.h> |
| | 20 | #include <linux/time.h> |
| | 21 | #include <linux/timex.h> |
| | 22 | #include <linux/smp.h> |
| | 23 | #include <linux/spinlock.h> |
| | 24 | #include <linux/export.h> |
| | 25 | |
| | 26 | #include <asm/cpu-features.h> |
| | 27 | #include <asm/div64.h> |
| | 28 | #include <asm/smtc_ipi.h> |
| | 29 | #include <asm/time.h> |
| | 30 | |
| | 31 | /* |
| | 32 | * forward reference |
| | 33 | */ |
| | 34 | DEFINE_SPINLOCK(rtc_lock); |
| | 35 | EXPORT_SYMBOL(rtc_lock); |
| | 36 | |
| | 37 | int __weak rtc_mips_set_time(unsigned long sec) |
| | 38 | { |
| | 39 | return 0; |
| | 40 | } |
| | 41 | |
| | 42 | int __weak rtc_mips_set_mmss(unsigned long nowtime) |
| | 43 | { |
| | 44 | return rtc_mips_set_time(nowtime); |
| | 45 | } |
| | 46 | |
| | 47 | int update_persistent_clock(struct timespec now) |
| | 48 | { |
| | 49 | return rtc_mips_set_mmss(now.tv_sec); |
| | 50 | } |
| | 51 | |
| | 52 | static int null_perf_irq(void) |
| | 53 | { |
| | 54 | return 0; |
| | 55 | } |
| | 56 | |
| | 57 | int (*perf_irq)(void) = null_perf_irq; |
| | 58 | |
| | 59 | EXPORT_SYMBOL(perf_irq); |
| | 60 | |
| | 61 | /* |
| | 62 | * time_init() - it does the following things. |
| | 63 | * |
| | 64 | * 1) plat_time_init() - |
| | 65 | * a) (optional) set up RTC routines, |
| | 66 | * b) (optional) calibrate and set the mips_hpt_frequency |
| | 67 | * (only needed if you intended to use cpu counter as timer interrupt |
| | 68 | * source) |
| | 69 | * 2) calculate a couple of cached variables for later usage |
| | 70 | */ |
| | 71 | |
| | 72 | unsigned int mips_hpt_frequency; |
| | 73 | |
| | 74 | /* |
| | 75 | * This function exists in order to cause an error due to a duplicate |
| | 76 | * definition if platform code should have its own implementation. The hook |
| | 77 | * to use instead is plat_time_init. plat_time_init does not receive the |
| | 78 | * irqaction pointer argument anymore. This is because any function which |
| | 79 | * initializes an interrupt timer now takes care of its own request_irq rsp. |
| | 80 | * setup_irq calls and each clock_event_device should use its own |
| | 81 | * struct irqrequest. |
| | 82 | */ |
| | 83 | void __init plat_timer_setup(void) |
| | 84 | { |
| | 85 | BUG(); |
| | 86 | } |
| | 87 | |
| | 88 | static __init int cpu_has_mfc0_count_bug(void) |
| | 89 | { |
| | 90 | switch (current_cpu_type()) { |
| | 91 | case CPU_R4000PC: |
| | 92 | case CPU_R4000SC: |
| | 93 | case CPU_R4000MC: |
| | 94 | /* |
| | 95 | * V3.0 is documented as suffering from the mfc0 from count bug. |
| | 96 | * Afaik this is the last version of the R4000. Later versions |
| | 97 | * were marketed as R4400. |
| | 98 | */ |
| | 99 | return 1; |
| | 100 | |
| | 101 | case CPU_R4400PC: |
| | 102 | case CPU_R4400SC: |
| | 103 | case CPU_R4400MC: |
| | 104 | /* |
| | 105 | * The published errata for the R4400 up to 3.0 say the CPU |
| | 106 | * has the mfc0 from count bug. |
| | 107 | */ |
| | 108 | if ((current_cpu_data.processor_id & 0xff) <= 0x30) |
| | 109 | return 1; |
| | 110 | |
| | 111 | /* |
| | 112 | * we assume newer revisions are ok |
| | 113 | */ |
| | 114 | return 0; |
| | 115 | } |
| | 116 | |
| | 117 | return 0; |
| | 118 | } |
| | 119 | |
| | 120 | void __init time_init(void) |
| | 121 | { |
| | 122 | plat_time_init(); |
| | 123 | |
| | 124 | if (!mips_clockevent_init() || !cpu_has_mfc0_count_bug()) |
| | 125 | init_mips_clocksource(); |
| | 126 | } |
projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / blame_incremental