Eric Lee / smarc-fsl-linux-kernel

03 May, 2007

1 commit

17 Feb, 2007

1 commit

  • e9e2cdb41   [PATCH] clockevents: i386 drivers ... Browse Code »

    Add clockevent drivers for i386: lapic (local) and PIT/HPET (global). Update
    the timer IRQ to call into the PIT/HPET driver's event handler and the
    lapic-timer IRQ to call into the lapic clockevent driver. The assignement of
    timer functionality is delegated to the core framework code and replaces the
    compile and runtime evalution in do_timer_interrupt_hook()

    Use the clockevents broadcast support and implement the lapic_broadcast
    function for ACPI.

    No changes to existing functionality.

    [ kdump fix from Vivek Goyal ]
    [ fixes based on review feedback from Arjan van de Ven ]
    Cleanups-from: Adrian Bunk
    Build-fixes-from: Andrew Morton
    Signed-off-by: Thomas Gleixner
    Signed-off-by: Ingo Molnar
    Cc: john stultz
    Cc: Roman Zippel
    Cc: Andi Kleen
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Thomas Gleixner
     

05 Oct, 2006

1 commit

  • 7d12e780e   IRQ: Maintain regs pointer globally rather than passing to IRQ handlers ... Browse Code »

    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
    (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

    David Howells
     

26 Apr, 2006

1 commit

10 Apr, 2006

1 commit

  • b20367a6c   [PATCH] x86_64: Fix drift with HPET timer enabled ... Browse Code »

    If the HPET timer is enabled, the clock can drift by ~3 seconds a day.
    This is due to the HPET timer not being initialized with the correct
    setting (still using PIT count).

    If HZ changes, this drift can become even more pronounced.

    HPET patch initializes tick_nsec with correct tick_nsec settings for
    HPET timer.

    Vojtech comments:

    "It's not entirely correct (it assumes the HPET ticks totally
    exactly), but it's significantly better than assuming the PIT error
    there."

    Signed-off-by: Andi Kleen
    Signed-off-by: Linus Torvalds

    Jordan Hargrave
     

01 May, 2005

1 commit

  • 35492df5a   [PATCH] i386: fix hpet for systems that don't support legacy replacement ... Browse Code »

    Currently the i386 HPET code assumes the entire HPET implementation from
    the spec is present. This breaks on boxes that do not implement the
    optional legacy timer replacement functionality portion of the spec.

    This patch, which is very similar to my x86-64 patch for the same issue,
    fixes the problem allowing i386 systems that cannot use the HPET for the
    timer interrupt and RTC to still use the HPET as a time source. I've
    tested this patch on a system systems without HPET, with HPET but without
    legacy timer replacement, as well as HPET with legacy timer replacement.

    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    john stultz
     

17 Apr, 2005

1 commit

  • 1da177e4c   Linux-2.6.12-rc2 ... Browse Code »

    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!

    Linus Torvalds