I've encountered a serious problem with PCI config space access on Au1x000
platforms with recent 2.6.x-kernel. With 2.4.31 the same hardware works fine.
So I was looking for the differences:

Symptoms:
- no PCI-device is seen on bootup though two or three cards are present
- lspci output is empty
- OR: lspci shows 20 times the same device
(- OR: in some slot-configurations it worked anyhow)

System(s):
1. platform with Au1500 and three PCI-devices (actually a mycable XXS1500
    with backplane for three PCI-devices)
2. platform with Au1550 and two PCI-devices (custom board)

Debugging:
I digged down to the config_access() of the au1xxx-processors in
arch/mips/pci/ops-au1000.c and switched on DEBUG.

The code of config_access() seems to be almost the same as of the
2.4.x-kernel. But the "pci_cfg_vm->addr" returned by get_vm_area(0x2000, 0)
once on booting is different. That's of course not forbidden. But the
alignment seems to be wrong. In my case, I received:

2.4.31: pci_cfg_vm->addr = c0000000
2.6.18-rc5: pci_cfg_vm->addr = c0101000

To make it short: With 2.6.x it fails on the first config-access with:
"PCI ERR detected: status 83a00356".

Fixup:
My fix is now, to use the VM_IOREMAP-flag in the get_vm_area call. This flag
seems to be introduced in mm/vmalloc.c a long time ago (in 2.6.7-bk13, I
found in gitweb).
Now, the returned address is pci_cfg_vm->addr = c0104000 and everything works
fine.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Since lmo commit 323a380bf9e1a1679a774a2b053e3c1f2aa3f179 ("Simplify
dump_stack()") made prepare_frametrace() always inlined, using $2 (v0)
in __asm__ is not safe anymore.  We can use $1 (at) instead.  Also we
should use "dla" instead of "la" for 64-bit kernel.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

c-r4k.c and c-sb1.c use drop_mmu_context() to flush virtually tagged
I-caches, but this does not work for flushing other task's icache.  This
is for example triggered by copy_to_user_page() called from ptrace(2).
Use indexed flush for such cases.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

XTC can only be set if VPA is clear, which it may not be. There is
also the possibility of a back to back c0 register access hazard to
take care of.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

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

dclz() expects its 64-bit argument being passed as a single register
but on 32-bit kernels it'll actually be in a register pair.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

... kconfig will do weird stuff.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The driver has not been merged yet so selecting it results in a warning
message.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

On the 34K the redundant cache operations were causing excessive stalls
resulting in realtime code running on the second VPE missing its deadline.
For all other platforms this patch is just a significant performance
improvment as illustrated by below benchmark numbers.

Processor, Processes - times in microseconds - smaller is better
------------------------------------------------------------------------------
Host                 OS  Mhz null null      open slct sig  sig  fork exec sh
                             call  I/O stat clos TCP  inst hndl proc proc proc
--------- ------------- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
25Kf      2.6.18-rc4     533 0.49 1.16 7.57 33.4 30.5 1.34 12.4 5497 17.K 54.K
25Kf      2.6.18-rc4-p   533 0.49 1.16 6.68 23.0 30.7 1.36 8.55 5030 16.K 48.K
4Kc       2.6.18-rc4      80 4.21 15.0 131. 289. 261. 16.5 258. 18.K 70.K 227K
4Kc       2.6.18-rc4-p    80 4.34 13.1 128. 285. 262. 18.2 258. 12.K 52.K 176K
34Kc      2.6.18-rc4      40 5.01 14.0 61.6 90.0 477. 17.9 94.7 29.K 108K 342K
34Kc      2.6.18-rc4-p    40 4.98 13.9 61.2 89.7 475. 17.6 93.7 8758 44.K 158K
BCM1480   2.6.18-rc4     700 0.28 0.60 3.68 5.92 16.0 0.78 5.08 931. 3163 15.K
BCM1480   2.6.18-rc4-p   700 0.28 0.61 3.65 5.85 16.0 0.79 5.20 395. 1464 8385
TX49-16K  2.6.18-rc3     197 0.73 2.41 19.0 37.8 82.9 2.94 17.5 4438 14.K 56.K
TX49-16K  2.6.18-rc3-p   197 0.73 2.40 19.9 36.3 82.9 2.94 23.4 2577 9103 38.K
TX49-32K  2.6.18-rc3     396 0.36 1.19 6.80 11.8 41.0 1.46 8.17 2738 8465 32.K
TX49-32K  2.6.18-rc3-p   396 0.36 1.19 6.82 10.2 41.0 1.46 8.18 1330 4638 18.K
    
Original patch by me with enhancements by Atsushi Nemoto.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>

In entry.S resume_userspace ... jal do_notify_resume form a loop through
which the kernel will iterate as long as work is pending.  If we
iterate through this loop more than once with no signal pending for at
least one but the last iteration we will take do the syscall restarting
multiple times resulting in a syscall return prior to the the syscall
instruction in userspace.  This may happen when debugging a multithreaded
program.

Debugging and original fix by Maciej; extended to other ABIs by me.
Signed-off-by: NMaciej W. Rozycki <macro@mips.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Recent 34Ks come out of reset with WP enabled on VPE 1 so we take an
immediate exception when starting the second VPE.
Signed-off-by: NChris Dearman <chris@mips.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NYoichi Yuasa <yoichi_yuasa@tripeaks.co.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>

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

CONFIG_IRQ_PER_CPU now controls the IRQ_PER_CPU stuff.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch allows unwind_stack() to return ra for leaf function.
But it tries to detects cases where get_frame_info() wrongly
consider nested function as a leaf one.

It also pass 'unsinged long *sp' instead of 'unsigned long **sp'
as second parameter. The code looks cleaner.
Signed-off-by: NFranck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Now get_frame_info() wants to detect move sp instruction first. It
assumes that the save ra in the stack instruction can't happen
before allocating frame size space into the stack.
Signed-off-by: NFranck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Make dump_stack() code not depend on CONFIG_KALLSYMS.

It also make prepare_frametrace() always inlined to get
less false entries reported by show_raw_backtrace().
Signed-off-by: NFranck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NFranck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

We usually use backtrace term for dumping a call tree during
debug. Therefore this patch renames show_frametrace() into
show_backtrace() and show_trace() into show_raw_backtrace().

It also uses the new function print_ip_sym().
Signed-off-by: NFranck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NFranck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NFranck Bui-Huu <vagabon.xyz@gmail.com>
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>

Instead of dump all possible address in the stack, unwind the stack frame
based on prologue code analysis, as like as get_wchan() does.  While the
code analysis might fail for some reason, there is a new kernel option
"raw_show_trace" to disable this feature.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

CONFIG_WM97XX_COMODULE doesn't exist.
Signed-off-by: NYoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Print call-trace in show_stack() (like on other archs).  Also make
show_trace() static and simplify its argument list.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NYoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NYoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NYoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NMaxime Bizon <mbizon@freebox.fr>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

* 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6: (225 commits)
  [PATCH] Don't set calgary iommu as default y
  [PATCH] i386/x86-64: New Intel feature flags
  [PATCH] x86: Add a cumulative thermal throttle event counter.
  [PATCH] i386: Make the jiffies compares use the 64bit safe macros.
  [PATCH] x86: Refactor thermal throttle processing
  [PATCH] Add 64bit jiffies compares (for use with get_jiffies_64)
  [PATCH] Fix unwinder warning in traps.c
  [PATCH] x86: Allow disabling early pci scans with pci=noearly or disallowing conf1
  [PATCH] x86: Move direct PCI scanning functions out of line
  [PATCH] i386/x86-64: Make all early PCI scans dependent on CONFIG_PCI
  [PATCH] Don't leak NT bit into next task
  [PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder
  [PATCH] Fix some broken white space in ia32_signal.c
  [PATCH] Initialize argument registers for 32bit signal handlers.
  [PATCH] Remove all traces of signal number conversion
  [PATCH] Don't synchronize time reading on single core AMD systems
  [PATCH] Remove outdated comment in x86-64 mmconfig code
  [PATCH] Use string instructions for Core2 copy/clear
  [PATCH] x86: - restore i8259A eoi status on resume
  [PATCH] i386: Split multi-line printk in oops output.
  ...

* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (47 commits)
  Driver core: Don't call put methods while holding a spinlock
  Driver core: Remove unneeded routines from driver core
  Driver core: Fix potential deadlock in driver core
  PCI: enable driver multi-threaded probe
  Driver Core: add ability for drivers to do a threaded probe
  sysfs: add proper sysfs_init() prototype
  drivers/base: check errors
  drivers/base: Platform notify needs to occur before drivers attach to the device
  v4l-dev2: handle __must_check
  add CONFIG_ENABLE_MUST_CHECK
  add __must_check to device management code
  Driver core: fixed add_bind_files() definition
  Driver core: fix comments in drivers/base/power/resume.c
  sysfs_remove_bin_file: no return value, dump_stack on error
  kobject: must_check fixes
  Driver core: add ability for devices to create and remove bin files
  Class: add support for class interfaces for devices
  Driver core: create devices/virtual/ tree
  Driver core: add device_rename function
  Driver core: add ability for classes to handle devices properly
  ...

Convert cmm's usage of kernel_thread to kthread_run.  Also create the
cmmthread at module load time, so it is possible to check if creation of
the thread fails.

In addition the cmmthread now gets terminated when the module gets unloaded
instead of leaving a stale kernel thread.  Also check the return values of
other registration functions at module load and handle their return values
appropriately.

Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Include the host architecture's ptrace-abi.h instead of ptrace.h.

There was some cpp mangling of names around the ptrace.h include to avoid
symbol clashes between UML and the host architecture.  Most of these can go
away.  The exception is struct pt_regs, which is convenient to have in
userspace, but must be renamed in order that UML can define its own.

ptrace-x86_64.h needed to have some now-obsolete cpp cruft and a declaration
removed.
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The use of SEGMENT_RPL_MASK in the i386 ptrace.h introduced by
x86-allow-a-kernel-to-not-be-in-ring-0.patch broke the UML build, as UML
includes the underlying architecture's ptrace.h, but has no easy access to the
x86 segment definitions.

Rather than kludging around this, as in the past, this patch splits the
userspace-usable parts, which are the bits that UML needs, of ptrace.h into
ptrace-abi.h, which is included back into ptrace.h.  Thus, there is no net
effect on i386.

As a side-effect, this creates a ptrace header which is close to being usable
in /usr/include.

x86_64 is also treated in this way for consistency.  There was some trailing
whitespace there, which is cleaned up.
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Ensure current->signal->tty doesn't get freed during log_exec().
Signed-off-by: NAlan Cox <alan@redhat.com>
Acked-by: NJeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The KSTK_* macros used an inordinate amount of stack.  In order to overcome
an impedance mismatch between their interface, which just returns a single
register value, and the interface of get_thread_regs, which took a full
pt_regs, the implementation created an on-stack pt_regs, filled it in, and
returned one field.  do_task_stat calls KSTK_* twice, resulting in two
local pt_regs, blowing out the stack.

This patch changes the interface (and name) of get_thread_regs to just
return a single register from a jmp_buf.

The include of archsetjmp.h" in registers.h to get the definition of
jmp_buf exposed a bogus include of <setjmp.h> in start_up.c.  <setjmp.h>
shouldn't be used anywhere any more since UML uses the klibc
setjmp/longjmp.
Signed-off-by: NJeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Clean set_ether_mac usage.  Maybe could also be removed, but surely it can't
be a global function taking a void* argument.
Signed-off-by: NPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: NJeff Dike <jdike@addtoit.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>