Commit Graph

23 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
Russell King db53f28b3a [MMC] Add multi block-write capability
Add a capability flag for drivers to set when they can perform multi-
block transfers to cards _and_ correctly report the number of bytes
transferred should an error occur.

The last point is very important - if a driver reports more bytes than
were actually accepted by the card and an error occurs, there is the
possibility for data loss.

Pierre Ossman provided the patch for wbsd and sdhci.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-09-16 11:57:49 +01:00
Russell King 3bc87f243f [MMC] Convert mmci to use data->blksz rather than data->blksz_bits
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-09-16 11:50:29 +01:00
Thomas Gleixner dace145374 [PATCH] irq-flags: misc drivers: Use the new IRQF_ constants
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 13:58:50 -07:00
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
Greg Kroah-Hartman e29419fffc [PATCH] 64bit resource: fix up printks for resources in misc drivers
This is needed if we wish to change the size of the resource structures.

Based on an original patch from Vivek Goyal <vgoyal@in.ibm.com>

Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-27 09:23:59 -07:00
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 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
Russell King 0425a14213 [MMC] mmci: allow small data transfers
If a data transfer is small (less than a FIFO size) we would
hang waiting for the data to be read due to the PIO interrupt
not occuring.  We allowed for this in our PIO interrupt handler,
but not when setting up a data transfer.

Apply the "fix" when setting up a data transfer as well.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-02-16 16:48:31 +00:00
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
Linus Torvalds 8995b161eb Merge master.kernel.org:/home/rmk/linux-2.6-arm 2006-01-07 10:45:22 -08:00
Russell King f8ce25476d [ARM] Move asm/hardware/clock.h to linux/clk.h
This is needs to be visible to other architectures using the AMBA
bus and peripherals.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-07 16:15:52 +00:00
Russell King a62c80e559 [ARM] Move AMBA include files to include/linux/amba/
Since the ARM AMBA bus is used on MIPS as well as ARM, we need
to make the bus available for other architectures to use.  Move
the AMBA include files from include/asm-arm/hardware/ to
include/linux/amba/

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-07 13:52:45 +00:00
Evgeniy Polyakov f3e2628bed [MMC] mmci: kunmap_atomic() unmaps virtual address, not page
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-05 10:31:23 +00:00
Russell King e9c091b474 [MMC] mmci: add data cache coherency
Since MMCI currently uses PIO to read data, we have to take steps
to ensure data cache coherency on aliasing CPU caches.  Add the
necessary flush_dcache_page() calls.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-04 16:24:05 +00:00
Russell King a8d3584a2d [ARM] Remove clk_use()/clk_unuse()
It seems that clk_use() and clk_unuse() are additional complexity
which isn't required anymore.  Remove them from the clock framework
to avoid the additional confusion which they cause, and update all
ARM machine types except for OMAP.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-01-03 18:41:37 +00:00
Russell King 69177e890c [MMC] mmci doesn't need asm/irq.h
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-11-12 17:26:21 +00:00
Russell King c6b8fdad14 [ARM] 3/4: Remove asm/hardware.h from Versatile and Integrator io.h
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-28 14:05:16 +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
Russell King d366b64363 [MMC] Add mmc_hostname() macro
mmc_hostname() returns a pointer to the hostname for the mmc_host.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-08-19 09:40:08 +01:00
Russell King 7b09cdac5a [PATCH] MMC: Fix divdi3 reference in mmci.c
Use do_div() instead.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-07-01 12:02:59 +01:00
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