menu "Kernel hacking"
  
  source "lib/Kconfig.debug"

  config DEBUG_STACKOVERFLOW
  	bool "Check for stack overflows"
  	depends on DEBUG_KERNEL
  	help
  	  This option will cause messages to be printed if free stack space
  	  drops below a certain limit.

  config DEBUG_VERBOSE
  	bool "Verbose fault messages"
  	default y
  	select PRINTK
  	help
  	  When a program crashes due to an exception, or the kernel detects
  	  an internal error, the kernel can print a not so brief message
  	  explaining what the problem was. This debugging information is
  	  useful to developers and kernel hackers when tracking down problems,
  	  but mostly meaningless to other people. This is always helpful for
  	  debugging but serves no purpose on a production system.
  	  Most people should say N here.

  config DEBUG_MMRS

  	tristate "Generate Blackfin MMR tree"

  	select DEBUG_FS
  	help
  	  Create a tree of Blackfin MMRs via the debugfs tree.  If
  	  you enable this, you will find all MMRs laid out in the
  	  /sys/kernel/debug/blackfin/ directory where you can read/write
  	  MMRs directly from userspace.  This is obviously just a debug
  	  feature.
  
  config DEBUG_HWERR
  	bool "Hardware error interrupt debugging"
  	depends on DEBUG_KERNEL
  	help
  	  When enabled, the hardware error interrupt is never disabled, and
  	  will happen immediately when an error condition occurs.  This comes
  	  at a slight cost in code size, but is necessary if you are getting
  	  hardware error interrupts and need to know where they are coming
  	  from.

  config EXACT_HWERR
  	bool "Try to make Hardware errors exact"
  	depends on DEBUG_HWERR
  	help
  	  By default, the Blackfin hardware errors are not exact - the error
            be reported multiple cycles after the error happens. This delay
  	  can cause the wrong application, or even the kernel to receive a
  	  signal to be killed. If you are getting HW errors in your system,

  	  try turning this on to ensure they are at least coming from the

  	  proper thread.
  
  	  On production systems, it is safe (and a small optimization) to say N.

  config DEBUG_DOUBLEFAULT
  	bool "Debug Double Faults"
  	default n
  	help
  	  If an exception is caused while executing code within the exception
  	  handler, the NMI handler, the reset vector, or in emulator mode,
  	  a double fault occurs. On the Blackfin, this is a unrecoverable
  	  event. You have two options:
  	  - RESET exactly when double fault occurs. The excepting
  	    instruction address is stored in RETX, where the next kernel
  	    boot will print it out.
  	  - Print debug message. This is much more error prone, although
  	    easier to handle. It is error prone since:
  	    - The excepting instruction is not committed.
  	    - All writebacks from the instruction are prevented.
  	    - The generated exception is not taken.
  	    - The EXCAUSE field is updated with an unrecoverable event
  	    The only way to check this is to see if EXCAUSE contains the
  	    unrecoverable event value at every exception return. By selecting
  	    this option, you are skipping over the faulting instruction, and 
  	    hoping things stay together enough to print out a debug message.
  
  	  This does add a little kernel code, but is the only method to debug
  	  double faults - if unsure say "Y"
  
  choice
  	prompt "Double Fault Failure Method"
  	default DEBUG_DOUBLEFAULT_PRINT
  	depends on DEBUG_DOUBLEFAULT
  
  config DEBUG_DOUBLEFAULT_PRINT
  	bool "Print"
  
  config DEBUG_DOUBLEFAULT_RESET
  	bool "Reset"
  
  endchoice

  config DEBUG_HUNT_FOR_ZERO
  	bool "Catch NULL pointer reads/writes"
  	default y
  	help
  	  Say Y here to catch reads/writes to anywhere in the memory range
  	  from 0x0000 - 0x0FFF (the first 4k) of memory.  This is useful in
  	  catching common programming errors such as NULL pointer dereferences.
  
  	  Misbehaving applications will be killed (generate a SEGV) while the
  	  kernel will trigger a panic.
  
  	  Enabling this option will take up an extra entry in CPLB table.
  	  Otherwise, there is no extra overhead.
  
  config DEBUG_BFIN_HWTRACE_ON
  	bool "Turn on Blackfin's Hardware Trace"
  	default y
  	help
  	  All Blackfins include a Trace Unit which stores a history of the last
  	  16 changes in program flow taken by the program sequencer. The history
  	  allows the user to recreate the program sequencer’s recent path. This
  	  can be handy when an application dies - we print out the execution
  	  path of how it got to the offending instruction.
  
  	  By turning this off, you may save a tiny amount of power.
  
  choice
  	prompt "Omit loop Tracing"
  	default DEBUG_BFIN_HWTRACE_COMPRESSION_OFF
  	depends on DEBUG_BFIN_HWTRACE_ON
  	help
  	  The trace buffer can be configured to omit recording of changes in
  	  program flow that match either the last entry or one of the last
  	  two entries. Omitting one of these entries from the record prevents
  	  the trace buffer from overflowing because of any sort of loop (for, do
  	  while, etc) in the program.
  
  	  Because zero-overhead Hardware loops are not recorded in the trace buffer,
  	  this feature can be used to prevent trace overflow from loops that
  	  are nested four deep.
  
  config DEBUG_BFIN_HWTRACE_COMPRESSION_OFF
  	bool "Trace all Loops"
  	help
  	  The trace buffer records all changes of flow 
  
  config DEBUG_BFIN_HWTRACE_COMPRESSION_ONE
  	bool "Compress single-level loops"
  	help
  	  The trace buffer does not record single loops - helpful if trace 
  	  is spinning on a while or do loop.
  
  config DEBUG_BFIN_HWTRACE_COMPRESSION_TWO
  	bool "Compress two-level loops"
  	help
  	  The trace buffer does not record loops two levels deep. Helpful if
  	  the trace is spinning in a nested loop
  
  endchoice
  
  config DEBUG_BFIN_HWTRACE_COMPRESSION
  	int
  	depends on DEBUG_BFIN_HWTRACE_ON
  	default 0 if DEBUG_BFIN_HWTRACE_COMPRESSION_OFF
  	default 1 if DEBUG_BFIN_HWTRACE_COMPRESSION_ONE
  	default 2 if DEBUG_BFIN_HWTRACE_COMPRESSION_TWO
  
  
  config DEBUG_BFIN_HWTRACE_EXPAND
  	bool "Expand Trace Buffer greater than 16 entries"
  	depends on DEBUG_BFIN_HWTRACE_ON
  	default n
  	help
  	  By selecting this option, every time the 16 hardware entries in
  	  the Blackfin's HW Trace buffer are full, the kernel will move them
  	  into a software buffer, for dumping when there is an issue. This 
  	  has a great impact on performance, (an interrupt every 16 change of 
  	  flows) and should normally be turned off, except in those nasty
  	  debugging sessions
  
  config DEBUG_BFIN_HWTRACE_EXPAND_LEN
  	int "Size of Trace buffer (in power of 2k)"
  	range 0 4
  	depends on DEBUG_BFIN_HWTRACE_EXPAND
  	default 1
  	help
  	  This sets the size of the software buffer that the trace information
  	  is kept in.
  	  0 for (2^0)  1k, or 256 entries,
  	  1 for (2^1)  2k, or 512 entries,
  	  2 for (2^2)  4k, or 1024 entries,
  	  3 for (2^3)  8k, or 2048 entries,
  	  4 for (2^4) 16k, or 4096 entries
  
  config DEBUG_BFIN_NO_KERN_HWTRACE

  	bool "Turn off hwtrace in CPLB handlers"

  	depends on DEBUG_BFIN_HWTRACE_ON

  	default y

  	help

  	  The CPLB error handler contains a lot of flow changes which can

  	  quickly fill up the hardware trace buffer.  When debugging crashes,
  	  the hardware trace may indicate that the problem lies in kernel
  	  space when in reality an application is buggy.
  
  	  Say Y here to disable hardware tracing in some known "jumpy" pieces
  	  of code so that the trace buffer will extend further back.
  
  config EARLY_PRINTK
  	bool "Early printk" 
  	default n

  	select SERIAL_CORE_CONSOLE

  	help
  	  This option enables special console drivers which allow the kernel
  	  to print messages very early in the bootup process.
  
  	  This is useful for kernel debugging when your machine crashes very
  	  early before the console code is initialized. After enabling this
  	  feature, you must add "earlyprintk=serial,uart0,57600" to the
  	  command line (bootargs). It is safe to say Y here in all cases, as
  	  all of this lives in the init section and is thrown away after the
  	  kernel boots completely.

  config NMI_WATCHDOG
  	bool "Enable NMI watchdog to help debugging lockup on SMP"
  	default n

  	depends on SMP

  	help
  	  If any CPU in the system does not execute the period local timer
  	  interrupt for more than 5 seconds, then the NMI handler dumps debug
  	  information. This information can be used to debug the lockup.

  config CPLB_INFO
  	bool "Display the CPLB information"
  	help

  	  Display the CPLB information via /proc/cplbinfo.

  
  config ACCESS_CHECK
  	bool "Check the user pointer address"
  	default y
  	help
  	  Usually the pointer transfer from user space is checked to see if its
  	  address is in the kernel space.
  
  	  Say N here to disable that check to improve the performance.

  config BFIN_ISRAM_SELF_TEST
  	bool "isram boot self tests"
  	default n
  	help
  	  Run some self tests of the isram driver code at boot.

  config BFIN_PSEUDODBG_INSNS
  	bool "Support pseudo debug instructions"
  	default n
  	help
  	  This option allows the kernel to emulate some pseudo instructions which
  	  allow simulator test cases to be run under Linux with no changes.
  
  	  Most people should say N here.

  endmenu