Commit Graph

20 Commits

Author SHA1 Message Date
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
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Pavel Pisa 2c171bf134 [ARM] 3531/1: i.MX/MX1 SD/MMC ensure, that clock are stopped before new command and cleanups
Patch from Pavel Pisa

There has been problems that for some paths that clock are not stopped
during new command programming and initiation. Result is issuing
of incorrect command to the card. Some other problems are cleaned too.
Noisy report of known ERRATUM #4 has been suppressed.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-05-19 21:48:03 +01:00
Russell King 920e70c5c6 [MMC] Move set_ios debugging into mmc.c
Rather than having every driver duplicate the set_ios debugging,
provide a single version in mmc.c which can be expanded as we
add additional functionality.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-05-04 18:22:51 +01:00
Russell King d78e9079af [MMC] PXA: reduce the number of lines PXAMCI debug uses
There's no reason for the PXAMCI debug code to print so many lines - it
causes the kernel buffer to overflow when trying to debug this driver.
Remove some debug messages which are duplicated by core code, and
combine other messages, resulting in fewer characters written to the
kernel log.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-05-02 20:18:53 +01:00
Russell King 58741e8b36 [MMC] PXA and i.MX: don't avoid sending stop command on error
Always send a stop command at the end of a data transfer.  If we avoid
sending the stop command, some cards remain in data transfer mode, and
refuse to accept further read/write commands.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-05-02 20:02:39 +01:00
Russell King 3d63abe56b [MMC] pxamci: fix data timeout calculation
The MMC layer gives us two parts for the timeout calculation - a fixed
timeout in nanoseconds, and a card clock-speed dependent part.

The PXA MMC hardware allows for a timeout based on the fixed host clock
speed only.  This resulted in some cards being given a short timeout,
and therefore failing to work.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-04-24 11:27:02 +01:00
Russell King c65631781e [MMC] Pass -DDEBUG on compiler command line if MMC_DEBUG selected
Rather than each driver test MMC_DEBUG itself, and define DEBUG,
pass it in via the makefile instead.

Fix drivers to use pr_debug() where appropriate, and avoid defining
a DEBUG() macro.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-03-29 09:30:20 +01:00
David Vrabel 489447380a [PATCH] handle errors returned by platform_get_irq*()
platform_get_irq*() now returns on -ENXIO when the resource cannot be
found.  Ensure all users of platform_get_irq*() handle this error
appropriately.

Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-20 13:42:57 -08:00
Russell King e92251762d [MMC] Add MMC command type flags
Some hosts need to know the command type, so pass it via a set of
flags in cmd->flags.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-02-02 12:23:12 +00:00
Russell King 3ae5eaec1d [DRIVER MODEL] Convert platform drivers to use struct platform_driver
This allows us to eliminate the casts in the drivers, and eventually
remove the use of the device_driver function pointer methods for
platform device drivers.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-09 22:32:44 +00:00
Linus Torvalds 4fd5f8267d Merge master.kernel.org:/home/rmk/linux-2.6-drvmodel
Manual #include fixups for clashes - there may be some unnecessary
2005-10-31 07:32:56 -08:00
Russell King 9e1d98c5d8 [MMC] pxamci doesn't need to include asm/irq.h
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-30 10:10:13 +00:00
Russell King d052d1beff Create platform_device.h to contain all the platform device details.
Convert everyone who uses platform_bus_type to include
linux/platform_device.h.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-29 19:07:23 +01:00
Russell King 9480e307cd [PATCH] DRIVER MODEL: Get rid of the obsolete tri-level suspend/resume callbacks
In PM v1, all devices were called at SUSPEND_DISABLE level.  Then
all devices were called at SUSPEND_SAVE_STATE level, and finally
SUSPEND_POWER_DOWN level.  However, with PM v2, to maintain
compatibility for platform devices, I arranged for the PM v2
suspend/resume callbacks to call the old PM v1 suspend/resume
callbacks three times with each level in order so that existing
drivers continued to work.

Since this is obsolete infrastructure which is no longer necessary,
we can remove it.  Here's an (untested) patch to do exactly that.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-28 09:52:56 -07:00
Richard Purdie c26971cbb3 [MMC] Add mmc_detect_change() delay support for PXAMCI driver
Allow PXA platforms to pass an appropriate delay value to the
PXA MCI driver for delaying detection changes.

Signed-Off-By: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-09-08 22:48:16 +01:00
Richard Purdie 8dc003359c [MMC] Allow detection/removal to be delayed
Change mmc_detect_change() to take a delay argument such that
the detection of card insertions and removals can be delayed
according to the requirements of the host driver or platform.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-09-08 17:53:01 +01:00
Richard Purdie e619524fe5 [PATCH] Add write protection switch handling to the PXA MMC driver
Add a write protection switch handling code to the PXA MMC driver so
that platform specific code can provide it if available.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:51 -07:00
Pavel Machek e5378ca8c0 [PATCH] fix u32 vs. pm_message_t in drivers/mmc,mtd,scsi
This fixes u32 vs.  pm_message_t in drivers/mmc, drivers/mtd and
drivers/scsi.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16 15:25:29 -07:00
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