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+menu "Kernel hacking"
+
+source "lib/Kconfig.debug"
+
+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.
+
+config BFIN_PM_WAKEUP_TIME_BENCH
+ bool "Display the total time for kernel to resume from power saving mode"
+ default n
+ help
+ Display the total time when kernel resumes normal from standby or
+ suspend to mem mode.
+
+endmenu