Commit Graph

24 Commits

Author SHA1 Message Date
Ralf Baechle
69e634f1e2 [MIPS] Clocksource: Only install r4k counter as clocksource if present.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-03-12 14:14:42 +00:00
Yoichi Yuasa
c9662341f8 [MIPS] time: remove unused mips_timer_state()
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-01-29 10:15:00 +00:00
Ralf Baechle
940f6b48a1 [MIPS] Only build r4k clocksource for systems that work ok with it.
In particular as-is it's not suited for multicore and mutiprocessors
systems where there is on guarantee that the counter are synchronized
or running from the same clock at all.  This broke Sibyte and probably
others since the "[MIPS] Handle R4000/R4400 mfc0 from count register."
commit.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-11-26 17:26:14 +00:00
Ralf Baechle
5aa85c9fc4 [MIPS] Handle R4000/R4400 mfc0 from count register.
The R4000 and R4400 have an errata where if the cp0 count register is read
in the exact moment when it matches the compare register no interrupt will
be generated.

This bug may be triggered if the cp0 count register is being used as
clocksource and the compare interrupt as clockevent.  So a simple
workaround is to avoid using the compare for both facilities on the
affected CPUs.

This is different from the workaround suggested in the old errata documents;
at some opportunity probably the official version should be implemented
and tested.  Another thing to find out is which processor versions
exactly are affected.  I only have errata documents upto R4400 V3.0
available so for the moment the code treats all R4000 and R4400 as broken.

This is potencially a problem for some machines that have no other decent
clocksource available; this workaround will cause them to fall back to
another clocksource, worst case the "jiffies" source.
2007-11-26 17:26:14 +00:00
Atsushi Nemoto
d9eec1a5d6 [MIPS] time: Code cleanups
* Do not include unnecessary headers.
* Do not mention time.README.
* Do not mention mips_timer_ack.
* Make clocksource_mips static.  It is now dedicated to c0_timer.
* Initialize clocksource_mips.read statically.
* Remove null_hpt_read.
* Remove an argument of plat_timer_setup.  It is just a placeholder.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-11-02 16:13:46 +00:00
Ralf Baechle
1d0a909cfc [MIPS] time: Remove now unused local_timer_interrupt.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-11-02 16:13:46 +00:00
Ralf Baechle
38760d40ca [MIPS] time: Replace plat_timer_setup with modern APIs.
plat_timer_setup is no longer getting called.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-29 19:35:36 +00:00
Ralf Baechle
0d0cc920de [MIPS] time: Remove declaration of plat_timer_setup, there is no caller.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-29 19:35:34 +00:00
Ralf Baechle
93c846f904 [MIPS] time: Helpers to compute clocksource/event shift and mult values.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-19 18:15:57 +01:00
Ralf Baechle
42f77542f4 [MIPS] time: Move R4000 clockevent device code to separate configurable file
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-18 18:11:47 +01:00
Ralf Baechle
2cfa7660db [MIPS] time: Delete dead cycles_per_jiffy, mips_timer_ack and null_timer_ack
cycles_per_jiffy was only ever getting assigned and the function pointer
not being called anymore and mips_timer_ack had gotten similarly stale.  I
leave the remaining assignments unfixed as a lighthouse pointing platform
maintainers to what needs a rewrite.  These changes make null_timer_ack()
unreferenced, so delete that too.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-18 18:11:47 +01:00
Ralf Baechle
7bcf7717b6 [MIPS] Implement clockevents for R4000-style cp0 count/compare interrupt
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-11 23:46:09 +01:00
Ralf Baechle
91a2fcc886 [MIPS] Consolidate all variants of MIPS cp0 timer interrupt handlers.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-11 23:46:09 +01:00
Ralf Baechle
90b02340dc [MIPS] Switch from to_tm to rtc_time_to_tm
This replaces the MIPS-specific to_tm function with the generic
rtc_time_to_tm function.  The big difference between the two functions is
that rtc_time_to_tm uses epoch 70 while to_tm uses 1970, so the result of
rtc_time_to_tm needs to be fixed up.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-11 23:46:09 +01:00
Ralf Baechle
4b550488f8 [MIPS] Deforest the function pointer jungle in the time code.
Hard to follow who is pointing what to where and why so it's simply getting
in the way of the time code renovation.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-11 23:46:08 +01:00
Atsushi Nemoto
005985609f [MIPS] mips HPT cleanup: make clocksource_mips public
Make clocksource_mips public and get rid of mips_hpt_read,
mips_hpt_mask.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:49 +00:00
Atsushi Nemoto
c87b6ebaea [MIPS] mips hpt cleanup: get rid of mips_hpt_init
Currently nobody outside time.c require mips_hpt_init().  Remove it
and call c0_hpt_timer_init() directly if R4k counter was used for
timer interrupt.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-11-30 01:14:46 +00:00
Atsushi Nemoto
16b7b2ac01 [MIPS] Fixup migration to GENERIC_TIME
Since we already moved to GENERIC_TIME, we should implement alternatives
of old do_gettimeoffset routines to get sub-jiffies resolution from
gettimeofday().  This patch includes:

 * MIPS clocksource support (based on works by Manish Lachwani).
 * remove unused gettimeoffset routines and related codes.
 * remove unised 64bit do_div64_32().
 * simplify mips_hpt_init. (no argument needed, __init tag)
 * simplify c0_hpt_timer_init. (no need to write to c0_count)
 * remove some hpt_init routines.
 * mips_hpt_mask variable to specify bitmask of hpt value.
 * convert jmr3927_do_gettimeoffset to jmr3927_hpt_read.
 * convert ip27_do_gettimeoffset to ip27_hpt_read.
 * convert bcm1480_do_gettimeoffset to bcm1480_hpt_read.
 * simplify sb1250 hpt functions. (no need to subtract and shift)
    
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-31 20:13:23 +00:00
Ralf Baechle
937a801576 [MIPS] Complete fixes after removal of pt_regs argument to int handlers.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-10-08 02:38:28 +01:00
David Howells
7d12e780e0 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 15:10:12 +01:00
Ralf Baechle
54d0a216f4 [MIPS] Replace board_timer_setup function pointer by plat_timer_setup.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

---
2006-07-13 21:26:17 +01:00
Yoichi Yuasa
d23ee8fe6e [PATCH] mips: fixed collision of rtc function name
Fix the collision of rtc function name.

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:50 -08:00
Atsushi Nemoto
53c2df2f4e Use rtc_lock to protect RTC operations
Many RTC routines were not protected against each other, so there are
potential races, for example, ntp-update against /dev/rtc.  This patch
fixes them using rtc_lock.
    
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-11-07 18:05:38 +00:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00