The previous patch wasn't correctly handling the 'count' variable.  If
a CPU gave bad results on the 1st or 2nd run but good results on the
3rd, it wouldn't do the correct thing.  No idea if any such CPU
exists, but the patch below handles that case by discarding the bad
runs.

If a bad result (too quick, or too slow) occurs on any of the 3 runs
it will be discarded.

Also updated some comments to explain what's going on.
Signed-off-by: NDave Johnson <djohnson@sw.starentnetworks.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

I ran into this problem on a system that was unable to obtain NTP sync
because the clock was running very slow (over 10000ppm slow). ntpd had
declared all of its peers 'reject' with 'peer_dist' reason.

On investigation, the tsc_khz variable was significantly incorrect
causing xtime to run slow.  After a reboot tsc_khz was correct so I
did a reboot test to see how often the problem occurred:

Test was done on a 2000 Mhz Xeon system.  Of 689 reboots, 8 of them
had unacceptable tsc_khz values (>500ppm):

 range of tsc_khz  # of boots  % of boots
 ----------------  ----------  ----------
        < 1999750           0      0.000%
1999750 - 1999800          21      3.048%
1999800 - 1999850         166     24.128%
1999850 - 1999900         241     35.029%
1999900 - 1999950         211     30.669%
1999950 - 2000000          42      6.105%
2000000 - 2000000           0      0.000%
2000050 - 2000100           0      0.000%
                   [...]
2000100 - 2015000           1      0.145%  << BAD
2015000 - 2030000           6      0.872%  << BAD
2030000 - 2045000           1      0.145%  << BAD
2045000 <                   0      0.000%

The worst boot was 2032.577 Mhz, over 1.5% off!

It appears that on rare occasions, mach_countup() is taking longer to
complete than necessary.

I suspect that this is caused by the CPU taking a periodic SMI
interrupt right at the end of the 30ms calibration loop.  This would
cause the loop to delay while the SMI BIOS hander runs. The resulting
TSC value is beyond what it actually should be resulting in a higher
tsc_khz.

The below patch makes native_calculate_cpu_khz() take the best
(shortest duration, lowest khz) run of it's 3 calibration loops.  If a
SMI goes off causing a bad result (long duration, higher khz) it will
be discarded.

With the patch applied, 300 boots of the same system produce good
results:

 range of tsc_khz  # of boots  % of boots
 ----------------  ----------  ----------
        < 1999750           0      0.000%
1999750 - 1999800          30     10.000%
1999800 - 1999850         166     55.333%
1999850 - 1999900          89     29.667%
1999900 - 1999950          15      5.000%
1999950 <                   0      0.000%

Problem was found and tested against 2.6.18.  Patch is against 2.6.22.
Signed-off-by: NDave Johnson <djohnson@sw.starentnetworks.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

It seems commit 09cadedb was incomplete 
due to a clash with the x86 architecture merge.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Reduce the function pointer mess of the m68knommu timer code by calling
directly to the local hardware's timer setup, and expose the local
common timer interrupt handler to the lower level hardware timer.

Ultimately this will save definitions of all these functions across all
the platform code to setup the function pointers (which for any given
m68knommu CPU family member can be only one set of hardware timer
functions).
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove build reference to arch/m68knommu/boot directory, it doesn't
exist.
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove use of undefined symbols CONFIG_TELOS, CONFIG_M68EZ328ADS
and CONFIG_ALMA_ANS.
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix system call restart handling. We can call directly to the
restart handler, no need to back track through trap that isn't
even implemented on m68knommu.
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add make support for the Savant/Rosie1 board.
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is no separate stack region addresses to print at startup time,
so remove it from the debug listing
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add configure support for the Savant/Rosie1 board.
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Updated defconfig with new options for m68knommu.
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix the system call code for handling syscall tracing, so strace
and gdbserver work properly.

This fix originally developed by Philippe De Muyter and Stuart Hughes.
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

zero out dma_length in the entry immediately following the last mapped
entry for unmap_sg.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NAlejandro Martinez Ruiz <alex@flawedcode.org>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Implement at32_add_device_cf() which will add a platform_device for
the at32_cf driver (not merged yet). Separate out most of the
at32_add_device_ide() code and use it to implement
at32_add_device_cf() as well.

This changes the API in the following ways:
  * The board code must initialize data->cs to the chipselect ID to
    use before calling any of these functions.
  * The board code must use GPIO_PIN_NONE to indicate unused CF pins.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Implement functions for adding platform devices for TWI, MCI, AC97C
and ABDAC. They may need to be modified to cope with platform data,
etc. when the corresponding drivers are ready to be merged, but such
changes are much less likely to conflict than adding support for a
whole new type of device.
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

Signed-off-by: NHans-Christian Egtvedt <hcegtvedt@atmel.com>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

This patch adds platform code for PATA devices on the AP7000.

[hskinnemoen@atmel.com: board code left out for now since stk1000
	doesn't support IDE out of the box]
Signed-off-by: NKristoffer Nyborg Gregertsen <kngregertsen@norway.atmel.com>
Signed-off-by: NHaavard Skinnemoen <hskinnemoen@atmel.com>

arch/parisc/kernel/pci-dma.c: In function 'pa11_dma_map_sg':
arch/parisc/kernel/pci-dma.c:487: error: 'struct scatterlist' has no member named 'page'
arch/parisc/kernel/pci-dma.c: In function 'pa11_dma_unmap_sg':
arch/parisc/kernel/pci-dma.c:508: error: 'struct scatterlist' has no member named 'page'
arch/parisc/kernel/pci-dma.c:508: error: 'struct scatterlist' has no member named 'page'
arch/parisc/kernel/pci-dma.c: In function 'pa11_dma_sync_sg_for_cpu':
arch/parisc/kernel/pci-dma.c:535: error: 'struct scatterlist' has no member named 'page'
arch/parisc/kernel/pci-dma.c:535: error: 'struct scatterlist' has no member named 'page'
arch/parisc/kernel/pci-dma.c: In function 'pa11_dma_sync_sg_for_device':
arch/parisc/kernel/pci-dma.c:545: error: 'struct scatterlist' has no member named 'page'
arch/parisc/kernel/pci-dma.c:545: error: 'struct scatterlist' has no member named 'page'
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

arch/arm/common/dmabounce.c: In function 'dma_map_sg':
arch/arm/common/dmabounce.c:445: error: implicit declaration of function 'sg_page'
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Version 2.07 of the boot protocol uses 0x23C for the hardware_subarch
field, that for lguest is "1".  This allows us to use the standard
boot entry point rather than the "GenuineLguest" string hack.

The standard entry point also clears the BSS and copies the boot parameters
and commandline for us, saving more code.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

This makes lguest able to use the virtio devices.

We change the device descriptor page from a simple array to a variable
length "type, config_len, status, config data..." format, and
implement virtio_config_ops to read from that config data.

We use the virtio ring implementation for an efficient Guest <-> Host
virtqueue mechanism, and the new LHCALL_NOTIFY hypercall to kick the
host when it changes.

We also use LHCALL_NOTIFY on kernel addresses for very very early
console output.  We could have another hypercall, but this hack works
quite well.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

This gets rid of the lguest bus, drivers and DMA mechanism, to make
way for a generic virtio mechanism.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

These helper routines supply most of the virtqueue_ops for hypervisors
which want to use a ring for virtio.  Unlike the previous lguest
implementation:

1) The rings are variable sized (2^n-1 elements).
2) They have an unfortunate limit of 65535 bytes per sg element.
3) The page numbers are always 64 bit (PAE anyone?)
4) They no longer place used[] on a separate page, just a separate
   cacheline.
5) We do a modulo on a variable.  We could be tricky if we cared.
6) Interrupts and notifies are suppressed using flags within the rings.

Users need only get the ring pages and provide a notify hook (KVM
wants the guest to allocate the rings, lguest does it sanely).
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Dor Laor <dor.laor@qumranet.com>

1) This allows us to get alot closer to booting bzImages.

2) It means we don't have to know page_offset.

3) The Guest needs to modify the boot pagetables to create the
   PAGE_OFFSET mapping before jumping to C code.

4) guest_pa() walks the page tables rather than using page_offset.

5) We don't use page_offset to figure out whether to emulate: it was
   always kinda quesationable, and won't work for instructions done
   before remapping (bzImage unpacking in particular).

6) We still want the kernel address for tlb flushing: have the initial
   hypercall give us that, too.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

(Based on Ron Minnich's LGUEST_PLAN9_SYSCALL patch).

This patch allows Guests to specify what system call vector they want,
and we try to reserve it.  We only allow one non-Linux system call
vector, to try to avoid DoS on the Host.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Clean up the hypercall code to make the code in hypercalls.c
architecture independent. First process the common hypercalls and
then call lguest_arch_do_hcall() if the call hasn't been handled.
Rename struct hcall_ring to hcall_args.

This patch requires the previous patch which reorganize the layout of
struct lguest_regs on i386 so they match the layout of struct
hcall_args.
Signed-off-by: NJes Sorensen <jes@sgi.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Separate i386 architecture specific from core.c and move it to
x86/core.c and add x86/lguest.h header file to match.
Signed-off-by: NJes Sorensen <jes@sgi.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Lguest has two sides: host support (to launch guests) and guest
support (replacement boot path and paravirt_ops).  This moves the
guest side to arch/x86/lguest where it's closer to related code.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>

1) Group all the "guest OS" support options together, under a PARAVIRT_GUEST
   menu.
2) Make those options select CONFIG_PARAVIRT, as suggested by Andi.
3) Make kconfig help titles consistent.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Chris Wright <chrisw@sous-sol.org>

Signed-off-by: NAlejandro Martinez Ruiz <alex@flawedcode.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use write_c0_compare(read_c0_count()) to clear interrupt.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

And make use of it for Cobalt.  A few others such as the Malta could make
use of it as well.
Signed-off-by: NYoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The BCM148 has 4 cores but there are also just 4 generic timers available
so use the ZBbus cycle counter instead of it.  In addition the ZBbus
counter also offers a much higher resolution and 64-bit counting so I'm
considering a later complete conversion to it once I figure out if all
members of the Sibyte SOC family support it - the docs seem to agree but
the headers files seem to disagree ...
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>