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)
Add the ability to have pxafb use only certain fixed video modes
(selected on a per platform basis). This is useful on production
hardware such as the Zaurus cxx00 models where the valid modes are
known in advance and any other modes could result in hardware damage.
Following this, add support for the cxx00 QVGA mode. Mode information
is passed to the lcd_power call to allowing the panel drivers to
configure the display hardware accordingly (corgi_lcd already contains
the functionality for the cxx00 panel).
This mirrors the setup already used by w100fb.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fixes for the pxafb driver:
* Return -EINVAL for resolutions that are too large as per framebuffer
driver policy.
* Increase the error timeout for disabling the LCD controller. The current
timeout is sometimes too short on the Sharp Zaurus Cxx00 hardware and an
extra delay in an error path shouldn't pose any problems.
* Fix a dev reference which causes a compile error when DEBUG is defined.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
No need for a file argument. If we'd really need it it's in vma->vm_file
already. gbefb and sgivwfb used to set vma->vm_file to the file argument, but
the kernel alrady did that.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
pxafb.c runs into an oops if CONFIG_FB_PXA_PARAMETERS is enabled and no
parameters are set in command line. The following patch avoids this
problem.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
According to Jon Smirl, filling in the field fb_cursor with soft_cursor for
drivers that do not support hardware cursors is redundant. The soft_cursor
function is usable by all drivers because it is just a wrapper around
fb_imageblit. And because soft_cursor is an fbcon-specific hook, the file is
moved to the console directory.
Thus, drivers that do not support hardware cursors can leave the fb_cursor
field blank. For drivers that do, they can fill up this field with their own
version.
The end result is a smaller code size. And if the framebuffer console is not
loaded, module/kernel size is also reduced because the soft_cursor module will
also not be loaded.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
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>
Fix warning:
drivers/video/pxafb.h:119:5: warning: "DEBUG" is not defined
by removing the whole
#if DEBUG
#define DPRINTK(fmt, args...) printk...etc...
#else
#define DPRINTK(fmt, args...)
#endif
stuff - we have pr_debug() for this.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
To solve touchscreen interference problems devices like the Sharp Zaurus
SL-C3000 need to know the length of the horitzontal sync pulses. This patch
adds a hook to pxafb so the touchscreen driver can function correctly.
Signed-Off-By: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This fixes u32 vs. pm_message_t confusion in drivers/video. Should change no
code.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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!
