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  1. 26 9月, 2007 2 次提交
  3. 23 9月, 2007 1 次提交
  5. 26 7月, 2007 1 次提交
  7. 15 5月, 2007 1 次提交
  9. 01 5月, 2007 2 次提交
  11. 22 4月, 2007 1 次提交
    • E
      [ARM] 4304/1: removes the unnecessary bit number from CKENnn_XXXX · 7053acbd
      由 Eric Miao 提交于 
      This patch removes the unnecessary bit number from CKENnn_XXXX
definitions for PXA, so that

	CKEN0_PWM0 --> CKEN_PWM0
	CKEN1_PWM1 --> CKEN_PWM1
	...
	CKEN24_CAMERA --> CKEN_CAMERA

The reasons for the change of these defitions are:

1. they do not scale - they are currently valid for pxa2xx, but
definitely not valid for pxa3xx, e.g., pxa3xx has bit 3 for camera
instead of bit 24

2. they are unnecessary - the peripheral name within the definition
has already announced its usage, we don't need those bit numbers
to know which peripheral we are going to enable/disable clock for

3. they are inconvenient - think about this: a driver programmer
for pxa has to remember which bit in the CKEN register to turn
on/off

Another change in the patch is to make the definitions equal to its
clock bit index, so that

   #define CKEN_CAMERA  (24)

instead of

   #define CKEN_CAMERA  (1 << 24)

this change, however, will add a run-time bit shift operation in
pxa_set_cken(), but the benefit of this change is that it scales
when bit index exceeds 32, e.g., pxa3xx has two registers CKENA
and CKENB, totally 64 bit for this, suppose CAMERA clock enabling
bit is CKENB:10, one can simply define CKEN_CAMERA to be (32 + 10)
and so that pxa_set_cken() need minimum change to adapt to that.
Signed-off-by: Neric miao <eric.y.miao@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      7053acbd
  13. 05 2月, 2007 2 次提交
  15. 15 1月, 2007 1 次提交
  17. 05 12月, 2006 1 次提交
  19. 02 12月, 2006 1 次提交
  21. 05 10月, 2006 1 次提交
    • D
      IRQ: Maintain regs pointer globally rather than passing to IRQ handlers · 7d12e780
      由 David Howells 提交于 
      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: NDavid Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
      7d12e780
  23. 01 7月, 2006 1 次提交
  25. 20 5月, 2006 1 次提交
  27. 05 5月, 2006 1 次提交
  29. 03 5月, 2006 2 次提交
  31. 24 4月, 2006 1 次提交
  33. 29 3月, 2006 1 次提交
  35. 21 3月, 2006 1 次提交
  37. 02 2月, 2006 1 次提交
  39. 10 11月, 2005 1 次提交
  41. 30 10月, 2005 2 次提交
  43. 29 10月, 2005 1 次提交
  45. 09 9月, 2005 2 次提交
  47. 08 9月, 2005 1 次提交
  49. 17 4月, 2005 2 次提交