2005-04-16 22:20:36 +00:00
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/*
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* Copyright 2001 MontaVista Software Inc.
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* Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
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* Copyright (c) 2003, 2004 Maciej W. Rozycki
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*
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* Common time service routines for MIPS machines. See
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* Documentation/mips/time.README.
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation; either version 2 of the License, or (at your
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* option) any later version.
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*/
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2007-10-11 22:46:09 +00:00
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#include <linux/clockchips.h>
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2005-04-16 22:20:36 +00:00
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/param.h>
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2007-09-13 04:13:28 +00:00
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#include <linux/profile.h>
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2005-04-16 22:20:36 +00:00
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#include <linux/time.h>
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#include <linux/timex.h>
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#include <linux/smp.h>
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#include <linux/kernel_stat.h>
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#include <linux/spinlock.h>
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#include <linux/interrupt.h>
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#include <linux/module.h>
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#include <asm/bootinfo.h>
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2005-07-13 11:48:45 +00:00
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#include <asm/cache.h>
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2005-04-16 22:20:36 +00:00
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#include <asm/compiler.h>
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#include <asm/cpu.h>
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#include <asm/cpu-features.h>
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#include <asm/div64.h>
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#include <asm/sections.h>
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#include <asm/time.h>
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2007-10-11 22:46:09 +00:00
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#include <irq.h>
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2005-04-16 22:20:36 +00:00
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/*
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* The integer part of the number of usecs per jiffy is taken from tick,
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* but the fractional part is not recorded, so we calculate it using the
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* initial value of HZ. This aids systems where tick isn't really an
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* integer (e.g. for HZ = 128).
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*/
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#define USECS_PER_JIFFY TICK_SIZE
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#define USECS_PER_JIFFY_FRAC ((unsigned long)(u32)((1000000ULL << 32) / HZ))
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#define TICK_SIZE (tick_nsec / 1000)
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/*
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* forward reference
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*/
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DEFINE_SPINLOCK(rtc_lock);
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2007-10-11 22:46:08 +00:00
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EXPORT_SYMBOL(rtc_lock);
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2005-04-16 22:20:36 +00:00
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2007-10-11 22:46:08 +00:00
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int __weak rtc_mips_set_time(unsigned long sec)
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2005-04-16 22:20:36 +00:00
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{
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2007-10-11 22:46:08 +00:00
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return 0;
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2005-04-16 22:20:36 +00:00
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}
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2007-10-11 22:46:08 +00:00
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EXPORT_SYMBOL(rtc_mips_set_time);
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2005-04-16 22:20:36 +00:00
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2007-10-11 22:46:08 +00:00
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int __weak rtc_mips_set_mmss(unsigned long nowtime)
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2005-04-16 22:20:36 +00:00
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{
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2007-10-11 22:46:08 +00:00
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return rtc_mips_set_time(nowtime);
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2005-04-16 22:20:36 +00:00
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}
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2007-08-13 14:26:12 +00:00
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int update_persistent_clock(struct timespec now)
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{
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return rtc_mips_set_mmss(now.tv_sec);
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}
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2005-04-16 22:20:36 +00:00
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/* how many counter cycles in a jiffy */
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2005-07-13 11:48:45 +00:00
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static unsigned long cycles_per_jiffy __read_mostly;
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2005-04-16 22:20:36 +00:00
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/*
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* Null timer ack for systems not needing one (e.g. i8254).
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*/
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static void null_timer_ack(void) { /* nothing */ }
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/*
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* Null high precision timer functions for systems lacking one.
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*/
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2006-11-11 15:10:28 +00:00
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static cycle_t null_hpt_read(void)
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2005-04-16 22:20:36 +00:00
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{
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return 0;
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}
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/*
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* Timer ack for an R4k-compatible timer of a known frequency.
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*/
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static void c0_timer_ack(void)
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{
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2007-10-11 22:46:09 +00:00
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write_c0_compare(read_c0_compare());
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2005-04-16 22:20:36 +00:00
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}
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/*
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* High precision timer functions for a R4k-compatible timer.
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*/
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2006-11-11 15:10:28 +00:00
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static cycle_t c0_hpt_read(void)
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2005-04-16 22:20:36 +00:00
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{
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return read_c0_count();
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}
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int (*mips_timer_state)(void);
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void (*mips_timer_ack)(void);
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/*
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* local_timer_interrupt() does profiling and process accounting
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* on a per-CPU basis.
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*
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* In UP mode, it is invoked from the (global) timer_interrupt.
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*
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* In SMP mode, it might invoked by per-CPU timer interrupt, or
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* a broadcasted inter-processor interrupt which itself is triggered
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* by the global timer interrupt.
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*/
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IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
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void local_timer_interrupt(int irq, void *dev_id)
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2005-04-16 22:20:36 +00:00
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{
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2006-10-07 18:44:33 +00:00
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profile_tick(CPU_PROFILING);
|
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
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update_process_times(user_mode(get_irq_regs()));
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2005-04-16 22:20:36 +00:00
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}
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|
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
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int null_perf_irq(void)
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2005-12-09 12:29:38 +00:00
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{
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return 0;
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}
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2007-10-11 22:46:09 +00:00
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EXPORT_SYMBOL(null_perf_irq);
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|
|
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
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int (*perf_irq)(void) = null_perf_irq;
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2005-12-09 12:29:38 +00:00
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EXPORT_SYMBOL(perf_irq);
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2007-06-20 21:27:10 +00:00
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/*
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* Timer interrupt
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*/
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int cp0_compare_irq;
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2007-05-24 21:24:20 +00:00
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/*
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* Performance counter IRQ or -1 if shared with timer
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*/
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2007-06-20 21:27:10 +00:00
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int cp0_perfcount_irq;
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EXPORT_SYMBOL_GPL(cp0_perfcount_irq);
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2007-05-24 21:24:20 +00:00
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/*
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* Possibly handle a performance counter interrupt.
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* Return true if the timer interrupt should not be checked
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*/
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static inline int handle_perf_irq (int r2)
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{
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/*
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* The performance counter overflow interrupt may be shared with the
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2007-06-20 21:27:10 +00:00
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* timer interrupt (cp0_perfcount_irq < 0). If it is and a
|
2007-05-24 21:24:20 +00:00
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* performance counter has overflowed (perf_irq() == IRQ_HANDLED)
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* and we can't reliably determine if a counter interrupt has also
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* happened (!r2) then don't check for a timer interrupt.
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*/
|
2007-06-20 21:27:10 +00:00
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return (cp0_perfcount_irq < 0) &&
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2007-05-24 21:24:20 +00:00
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perf_irq() == IRQ_HANDLED &&
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!r2;
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}
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|
2005-04-16 22:20:36 +00:00
|
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/*
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* time_init() - it does the following things.
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*
|
2007-10-11 22:46:08 +00:00
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|
|
* 1) plat_time_init() -
|
2005-04-16 22:20:36 +00:00
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* a) (optional) set up RTC routines,
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* b) (optional) calibrate and set the mips_hpt_frequency
|
2006-10-23 15:21:27 +00:00
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* (only needed if you intended to use cpu counter as timer interrupt
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* source)
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2007-10-11 22:46:08 +00:00
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* 2) calculate a couple of cached variables for later usage
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* 3) plat_timer_setup() -
|
2005-04-16 22:20:36 +00:00
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* a) (optional) over-write any choices made above by time_init().
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* b) machine specific code should setup the timer irqaction.
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* c) enable the timer interrupt
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*/
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unsigned int mips_hpt_frequency;
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static unsigned int __init calibrate_hpt(void)
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|
{
|
2006-11-11 15:10:28 +00:00
|
|
|
cycle_t frequency, hpt_start, hpt_end, hpt_count, hz;
|
2005-04-16 22:20:36 +00:00
|
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const int loops = HZ / 10;
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int log_2_loops = 0;
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int i;
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/*
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* We want to calibrate for 0.1s, but to avoid a 64-bit
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* division we round the number of loops up to the nearest
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* power of 2.
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*/
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while (loops > 1 << log_2_loops)
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log_2_loops++;
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i = 1 << log_2_loops;
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/*
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* Wait for a rising edge of the timer interrupt.
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*/
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|
while (mips_timer_state());
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|
while (!mips_timer_state());
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|
|
|
|
|
|
|
/*
|
|
|
|
* Now see how many high precision timer ticks happen
|
|
|
|
* during the calculated number of periods between timer
|
|
|
|
* interrupts.
|
|
|
|
*/
|
2006-11-11 15:10:28 +00:00
|
|
|
hpt_start = clocksource_mips.read();
|
2005-04-16 22:20:36 +00:00
|
|
|
do {
|
|
|
|
while (mips_timer_state());
|
|
|
|
while (!mips_timer_state());
|
|
|
|
} while (--i);
|
2006-11-11 15:10:28 +00:00
|
|
|
hpt_end = clocksource_mips.read();
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2006-11-11 15:10:28 +00:00
|
|
|
hpt_count = (hpt_end - hpt_start) & clocksource_mips.mask;
|
2005-04-16 22:20:36 +00:00
|
|
|
hz = HZ;
|
2006-11-11 15:10:28 +00:00
|
|
|
frequency = hpt_count * hz;
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
return frequency >> log_2_loops;
|
|
|
|
}
|
|
|
|
|
2006-11-11 15:10:28 +00:00
|
|
|
struct clocksource clocksource_mips = {
|
2006-10-23 15:21:27 +00:00
|
|
|
.name = "MIPS",
|
2007-05-04 15:36:44 +00:00
|
|
|
.mask = CLOCKSOURCE_MASK(32),
|
2007-02-16 09:27:40 +00:00
|
|
|
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
|
2006-10-23 15:21:27 +00:00
|
|
|
};
|
|
|
|
|
2007-10-11 22:46:09 +00:00
|
|
|
static int mips_next_event(unsigned long delta,
|
|
|
|
struct clock_event_device *evt)
|
|
|
|
{
|
|
|
|
unsigned int cnt;
|
|
|
|
|
|
|
|
cnt = read_c0_count();
|
|
|
|
cnt += delta;
|
|
|
|
write_c0_compare(cnt);
|
|
|
|
|
|
|
|
return ((long)(read_c0_count() - cnt ) > 0) ? -ETIME : 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void mips_set_mode(enum clock_event_mode mode,
|
|
|
|
struct clock_event_device *evt)
|
|
|
|
{
|
|
|
|
/* Nothing to do ... */
|
|
|
|
}
|
|
|
|
|
|
|
|
struct clock_event_device mips_clockevent;
|
|
|
|
|
|
|
|
static struct clock_event_device *global_cd[NR_CPUS];
|
|
|
|
static int cp0_timer_irq_installed;
|
|
|
|
|
|
|
|
static irqreturn_t timer_interrupt(int irq, void *dev_id)
|
|
|
|
{
|
|
|
|
const int r2 = cpu_has_mips_r2;
|
|
|
|
struct clock_event_device *cd;
|
|
|
|
int cpu = smp_processor_id();
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Suckage alert:
|
|
|
|
* Before R2 of the architecture there was no way to see if a
|
|
|
|
* performance counter interrupt was pending, so we have to run
|
|
|
|
* the performance counter interrupt handler anyway.
|
|
|
|
*/
|
|
|
|
if (handle_perf_irq(r2))
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* The same applies to performance counter interrupts. But with the
|
|
|
|
* above we now know that the reason we got here must be a timer
|
|
|
|
* interrupt. Being the paranoiacs we are we check anyway.
|
|
|
|
*/
|
|
|
|
if (!r2 || (read_c0_cause() & (1 << 30))) {
|
|
|
|
c0_timer_ack();
|
|
|
|
cd = global_cd[cpu];
|
|
|
|
cd->event_handler(cd);
|
|
|
|
}
|
|
|
|
|
|
|
|
out:
|
|
|
|
return IRQ_HANDLED;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct irqaction timer_irqaction = {
|
|
|
|
.handler = timer_interrupt,
|
|
|
|
.flags = IRQF_DISABLED | IRQF_PERCPU,
|
|
|
|
.name = "timer",
|
|
|
|
};
|
|
|
|
|
2006-10-23 15:21:27 +00:00
|
|
|
static void __init init_mips_clocksource(void)
|
|
|
|
{
|
|
|
|
u64 temp;
|
|
|
|
u32 shift;
|
|
|
|
|
2006-11-11 15:10:28 +00:00
|
|
|
if (!mips_hpt_frequency || clocksource_mips.read == null_hpt_read)
|
2006-10-23 15:21:27 +00:00
|
|
|
return;
|
|
|
|
|
|
|
|
/* Calclate a somewhat reasonable rating value */
|
|
|
|
clocksource_mips.rating = 200 + mips_hpt_frequency / 10000000;
|
|
|
|
/* Find a shift value */
|
|
|
|
for (shift = 32; shift > 0; shift--) {
|
|
|
|
temp = (u64) NSEC_PER_SEC << shift;
|
|
|
|
do_div(temp, mips_hpt_frequency);
|
|
|
|
if ((temp >> 32) == 0)
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
clocksource_mips.shift = shift;
|
|
|
|
clocksource_mips.mult = (u32)temp;
|
|
|
|
|
|
|
|
clocksource_register(&clocksource_mips);
|
|
|
|
}
|
|
|
|
|
2007-10-11 22:46:08 +00:00
|
|
|
void __init __weak plat_time_init(void)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2007-10-11 22:46:08 +00:00
|
|
|
}
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2007-10-11 22:46:09 +00:00
|
|
|
void __init __weak plat_timer_setup(struct irqaction *irq)
|
|
|
|
{
|
|
|
|
}
|
|
|
|
|
|
|
|
void __cpuinit mips_clockevent_init(void)
|
|
|
|
{
|
|
|
|
uint64_t mips_freq = mips_hpt_frequency;
|
|
|
|
unsigned int cpu = smp_processor_id();
|
|
|
|
struct clock_event_device *cd;
|
|
|
|
unsigned int irq = MIPS_CPU_IRQ_BASE + 7;
|
|
|
|
|
|
|
|
if (!cpu_has_counter)
|
|
|
|
return;
|
|
|
|
|
|
|
|
if (cpu == 0)
|
|
|
|
cd = &mips_clockevent;
|
|
|
|
else
|
|
|
|
cd = kzalloc(sizeof(*cd), GFP_ATOMIC);
|
|
|
|
if (!cd)
|
|
|
|
return; /* We're probably roadkill ... */
|
|
|
|
|
|
|
|
cd->name = "MIPS";
|
|
|
|
cd->features = CLOCK_EVT_FEAT_ONESHOT;
|
|
|
|
|
|
|
|
/* Calculate the min / max delta */
|
|
|
|
cd->mult = div_sc((unsigned long) mips_freq, NSEC_PER_SEC, 32);
|
|
|
|
cd->shift = 32;
|
|
|
|
cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd);
|
|
|
|
cd->min_delta_ns = clockevent_delta2ns(0x30, cd);
|
|
|
|
|
|
|
|
cd->rating = 300;
|
|
|
|
cd->irq = irq;
|
|
|
|
cd->cpumask = cpumask_of_cpu(cpu);
|
|
|
|
cd->set_next_event = mips_next_event;
|
|
|
|
cd->set_mode = mips_set_mode;
|
|
|
|
|
|
|
|
global_cd[cpu] = cd;
|
|
|
|
clockevents_register_device(cd);
|
|
|
|
|
|
|
|
if (!cp0_timer_irq_installed) {
|
|
|
|
#ifdef CONFIG_MIPS_MT_SMTC
|
|
|
|
#define CPUCTR_IMASKBIT (0x100 << cp0_compare_irq)
|
|
|
|
setup_irq_smtc(irq, &timer_irqaction, CPUCTR_IMASKBIT);
|
|
|
|
#else
|
|
|
|
setup_irq(irq, &timer_irqaction);
|
|
|
|
#endif /* CONFIG_MIPS_MT_SMTC */
|
|
|
|
cp0_timer_irq_installed = 1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2007-10-11 22:46:08 +00:00
|
|
|
void __init time_init(void)
|
|
|
|
{
|
|
|
|
plat_time_init();
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/* Choose appropriate high precision timer routines. */
|
2006-11-11 15:10:28 +00:00
|
|
|
if (!cpu_has_counter && !clocksource_mips.read)
|
2005-04-16 22:20:36 +00:00
|
|
|
/* No high precision timer -- sorry. */
|
2006-11-11 15:10:28 +00:00
|
|
|
clocksource_mips.read = null_hpt_read;
|
2006-10-23 15:21:27 +00:00
|
|
|
else if (!mips_hpt_frequency && !mips_timer_state) {
|
2005-04-16 22:20:36 +00:00
|
|
|
/* A high precision timer of unknown frequency. */
|
2006-11-11 15:10:28 +00:00
|
|
|
if (!clocksource_mips.read)
|
2005-04-16 22:20:36 +00:00
|
|
|
/* No external high precision timer -- use R4k. */
|
2006-11-11 15:10:28 +00:00
|
|
|
clocksource_mips.read = c0_hpt_read;
|
2005-04-16 22:20:36 +00:00
|
|
|
} else {
|
|
|
|
/* We know counter frequency. Or we can get it. */
|
2006-11-11 15:10:28 +00:00
|
|
|
if (!clocksource_mips.read) {
|
2005-04-16 22:20:36 +00:00
|
|
|
/* No external high precision timer -- use R4k. */
|
2006-11-11 15:10:28 +00:00
|
|
|
clocksource_mips.read = c0_hpt_read;
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2006-10-23 15:21:27 +00:00
|
|
|
if (!mips_timer_state) {
|
2005-04-16 22:20:36 +00:00
|
|
|
/* No external timer interrupt -- use R4k. */
|
|
|
|
mips_timer_ack = c0_timer_ack;
|
2006-10-27 16:14:37 +00:00
|
|
|
/* Calculate cache parameters. */
|
|
|
|
cycles_per_jiffy =
|
|
|
|
(mips_hpt_frequency + HZ / 2) / HZ;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
if (!mips_hpt_frequency)
|
|
|
|
mips_hpt_frequency = calibrate_hpt();
|
|
|
|
|
|
|
|
/* Report the high precision timer rate for a reference. */
|
|
|
|
printk("Using %u.%03u MHz high precision timer.\n",
|
|
|
|
((mips_hpt_frequency + 500) / 1000) / 1000,
|
|
|
|
((mips_hpt_frequency + 500) / 1000) % 1000);
|
2007-10-11 22:46:09 +00:00
|
|
|
|
|
|
|
#ifdef CONFIG_IRQ_CPU
|
|
|
|
setup_irq(MIPS_CPU_IRQ_BASE + 7, &timer_irqaction);
|
|
|
|
#endif
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
if (!mips_timer_ack)
|
|
|
|
/* No timer interrupt ack (e.g. i8254). */
|
|
|
|
mips_timer_ack = null_timer_ack;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Call board specific timer interrupt setup.
|
|
|
|
*
|
|
|
|
* this pointer must be setup in machine setup routine.
|
|
|
|
*
|
|
|
|
* Even if a machine chooses to use a low-level timer interrupt,
|
|
|
|
* it still needs to setup the timer_irqaction.
|
|
|
|
* In that case, it might be better to set timer_irqaction.handler
|
|
|
|
* to be NULL function so that we are sure the high-level code
|
|
|
|
* is not invoked accidentally.
|
|
|
|
*/
|
2006-07-09 20:38:56 +00:00
|
|
|
plat_timer_setup(&timer_irqaction);
|
2006-10-23 15:21:27 +00:00
|
|
|
|
|
|
|
init_mips_clocksource();
|
2007-10-11 22:46:09 +00:00
|
|
|
mips_clockevent_init();
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|