Sometimes when we crash, current is not valid, (has been written
over), so the existing code causes a invalid read during exception
context - which is a unrecoverable double fault. This fixes this.
Signed-off-by: NRobin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: NBryan Wu <cooloney@kernel.org>

[Blackfin] arch: add missing __user marking to ss_sp member of signalstack and a few userspace system functions
Signed-off-by: NMike Frysinger <vapier.adi@gmail.com>
Signed-off-by: NBryan Wu <cooloney@kernel.org>

d_path() is used on a <dentry,vfsmount> pair.  Lets use a struct path to
reflect this.

[akpm@linux-foundation.org: fix build in mm/memory.c]
Signed-off-by: NJan Blunck <jblunck@suse.de>
Acked-by: NBryan Wu <bryan.wu@analog.com>
Acked-by: NChristoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NMike Frysinger <vapier.adi@gmail.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Blackfin arch: split apart dump_bfin_regs and merge/remove show_regs from process.c, which was largely duplicated
Signed-off-by: NMike Frysinger <michael.frysinger@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

We need to send signals with the proper PC, or gdb gets
confused, and lots of tests fail. This should fix that.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

[Blackfin] arch: print out list of modules if kernel is crashing and tell people if the kernel is tainted 
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Don't oops_in_progress if single step is comming from the
kernel, which happens if a single step occurs after a exception cause.
This fixes up the remaining issues in the toolchain bug.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Clean up dump_bfin_mem so that it will display
content from the kernel, as well as l1 instruction, when deferred
HW errors happen, print out the last frame info if it makes sense.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

http://blackfin.uclinux.org/gf/project/toolchain/tracker/?action=TrackerItemEdit&tracker_item_id=3651

As Bernd predicted, this was only necessary because of other
problems in the kenel - fixing those, and this is not necessary, so
remove it.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3719

When the CPLBs get a miss, we do:
  - find a victim in the HW table
  - remove the victim
  - find the replacement in the software table
  - put it into the HW table.

If we can't find a replacement in the software table, we accidently
leave a duplicate in the HW table. This patch ensures that duplicate
is marked as not valid.

What we should do is find the replacement in the software table, before
we find a victim in the HW table - but its too late in the release cycle
to do that much restructuring of this code.

Rather that duplicate code, connect Hardware Errors (irq5) into trap_c,
so user space processes get killed properly.

The rest of irq_panic() can be moved into traps.c (later)

There is still a small corner case that causes problems when a
pheriperal interrupt goes off a single cycle before a user space
hardware error. This causes a kernel panic, rather than the user
space process being killed.

But, this checkin makes things work in 99.9% of the cases, and is a vast
improvement from what is there today (which fails 100% of the time).
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

https://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=1685

Ensure that cache/protection is turned back on when we get a
fault, and ensure that the initial population of the CPLB tables are
correct - that kernel is locked in CPLB tables
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

 We currently do not. Also make it easier to handle cplb violations - in traps.c
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

 - move the CONFIG_KGDB into one block, for easier reading
 - remove printk from printk_address, and pass around buffers. Also
   print out the labels when decoding CPLB errors, so you know exactly
   where the error was.
 - Do not use fixed addresses, becuase people do not know where they come from.
 - Turn the printing level down on the dump, so if you don't want,
   only the signal prints out - just like on other archs. If a kernel/interrupt
   crashes, it should dump everything all the time
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

This fixes two things:
 - stop calling write_lock_irq/write_unlock_irq which can turn modify
   irq levels
 - don't calling mmput when handing exceptions - since this might_sleep,
   which does a rti, and leaves us in kernel space (irq15, rather
   than irq5).
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

We must balance calls to get_task_mm with corresponding mmput calls, otherwise
refcounting is screwed up and mms don't get freed when their task exits.
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Blackfin arch: Enable earlyprintk earlier - so any error after our interrupt tables are set up will print out

Also ensure that the traps_c code doesn't cause a double fault, by
sending a signal to a faulting kernel before the memory subsystem
is fully initialized, by printing out the error message before sending
the signal.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Today when a double fault happens (exception during an exception
handling event), we go into an endless loop, with nothing comming out
the UART. With this patch, we actually see that we have commited a
double fault event
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

add an exception request/free api similar to the interrupt request/fre
api so people can utilize the free software based exceptions for their
own purposes
Signed-off-by: NMike Frysinger <michael.frysinger@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NMike Frysinger <michael.frysinger@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Add ability to expend the hardware trace buffer via a configurable
software buffer - so you can have lots of history when a crash occurs.

The interesting way we do printk in the traps.c confusese the checking
script
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

we converted to using a system call for userspace spinlocks
rather than a dedicated exception long ago
Signed-off-by: NMike Frysinger <michael.frysinger@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NMike Frysinger <michael.frysinger@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Turns on trace earlier, so crashes at kernel start should print out a
trace, making things easier to debug.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <michael.frysinger@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

to look like:

return address: [0x0357fcc4]; contents of:
0x0357fca0:  fcbc  0357  fe20  0357  0009  0000  6a8c  0345
0x0357fcb0:  000e  0000  fcc4  0357  fd44  0357  e128  00ad
0x0357fcc0:  00a0  0000 [000e] 0000  0000  0000  0080  0000
0x0357fcd0:  0000  0000  0000  0000  00a0  0000  000e  0000

instruction in [] is the offending instruction
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NSimon Arlott <simon@fire.lp0.eu>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Signed-off-by: NMike Frysinger <michael.frysinger@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This adds support for the Analog Devices Blackfin processor architecture, and
currently supports the BF533, BF532, BF531, BF537, BF536, BF534, and BF561
(Dual Core) devices, with a variety of development platforms including those
avaliable from Analog Devices (BF533-EZKit, BF533-STAMP, BF537-STAMP,
BF561-EZKIT), and Bluetechnix!  Tinyboards.

The Blackfin architecture was jointly developed by Intel and Analog Devices
Inc.  (ADI) as the Micro Signal Architecture (MSA) core and introduced it in
December of 2000.  Since then ADI has put this core into its Blackfin
processor family of devices.  The Blackfin core has the advantages of a clean,
orthogonal,RISC-like microprocessor instruction set.  It combines a dual-MAC
(Multiply/Accumulate), state-of-the-art signal processing engine and
single-instruction, multiple-data (SIMD) multimedia capabilities into a single
instruction-set architecture.

The Blackfin architecture, including the instruction set, is described by the
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
http://blackfin.uclinux.org/gf/download/frsrelease/29/2549/Blackfin_PRM.pdf

The Blackfin processor is already supported by major releases of gcc, and
there are binary and source rpms/tarballs for many architectures at:
http://blackfin.uclinux.org/gf/project/toolchain/frs There is complete
documentation, including "getting started" guides available at:
http://docs.blackfin.uclinux.org/ which provides links to the sources and
patches you will need in order to set up a cross-compiling environment for
bfin-linux-uclibc

This patch, as well as the other patches (toolchain, distribution,
uClibc) are actively supported by Analog Devices Inc, at:
http://blackfin.uclinux.org/

We have tested this on LTP, and our test plan (including pass/fails) can
be found at:
http://docs.blackfin.uclinux.org/doku.php?id=testing_the_linux_kernel

[m.kozlowski@tuxland.pl: balance parenthesis in blackfin header files]
Signed-off-by: NBryan Wu <bryan.wu@analog.com>
Signed-off-by: NMariusz Kozlowski <m.kozlowski@tuxland.pl>
Signed-off-by: NAubrey Li <aubrey.li@analog.com>
Signed-off-by: NJie Zhang <jie.zhang@analog.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>