[deliverable/linux.git] / arch / blackfin / Kconfig.debug

menu "Kernel hacking"

source "lib/Kconfig.debug"

config DEBUG_MMRS
	bool "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 DEBUG_ICACHE_CHECK
	bool "Check Instruction cache coherency"
	depends on DEBUG_KERNEL
	depends on DEBUG_HWERR
	help
	  Say Y here if you are getting weird unexplained errors. This will
	  ensure that icache is what SDRAM says it should be by doing a
	  byte wise comparison between SDRAM and instruction cache. This
	  also relocates the irq_panic() function to L1 memory, (which is
	  un-cached).

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 "Trace user apps (turn off hwtrace in kernel)"
	depends on DEBUG_BFIN_HWTRACE_ON
	default n
	help
	  Some pieces of the kernel contain 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
	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 DUAL_CORE_TEST_MODULE
	tristate "Dual Core Test Module"
	depends on (BF561)
	default n
	help
	  Say Y here to build-in dual core test module for dual core test.

config CPLB_INFO
	bool "Display the CPLB information"
	help
	  Display the CPLB information.

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.

endmenu
Commit	Line	Data
74ce8322 MF	1	menu "Kernel hacking"
	2
	3	source "lib/Kconfig.debug"
	4
	5	config DEBUG_MMRS
	6	bool "Generate Blackfin MMR tree"
	7	select DEBUG_FS
	8	help
	9	Create a tree of Blackfin MMRs via the debugfs tree. If
	10	you enable this, you will find all MMRs laid out in the
	11	/sys/kernel/debug/blackfin/ directory where you can read/write
	12	MMRs directly from userspace. This is obviously just a debug
	13	feature.
	14
	15	config DEBUG_HWERR
	16	bool "Hardware error interrupt debugging"
	17	depends on DEBUG_KERNEL
	18	help
	19	When enabled, the hardware error interrupt is never disabled, and
	20	will happen immediately when an error condition occurs. This comes
	21	at a slight cost in code size, but is necessary if you are getting
	22	hardware error interrupts and need to know where they are coming
	23	from.
	24
	25	config DEBUG_ICACHE_CHECK
	26	bool "Check Instruction cache coherency"
	27	depends on DEBUG_KERNEL
	28	depends on DEBUG_HWERR
	29	help
	30	Say Y here if you are getting weird unexplained errors. This will
	31	ensure that icache is what SDRAM says it should be by doing a
	32	byte wise comparison between SDRAM and instruction cache. This
	33	also relocates the irq_panic() function to L1 memory, (which is
	34	un-cached).
	35
	36	config DEBUG_HUNT_FOR_ZERO
	37	bool "Catch NULL pointer reads/writes"
	38	default y
	39	help
	40	Say Y here to catch reads/writes to anywhere in the memory range
	41	from 0x0000 - 0x0FFF (the first 4k) of memory. This is useful in
	42	catching common programming errors such as NULL pointer dereferences.
	43
	44	Misbehaving applications will be killed (generate a SEGV) while the
	45	kernel will trigger a panic.
	46
	47	Enabling this option will take up an extra entry in CPLB table.
	48	Otherwise, there is no extra overhead.
	49
	50	config DEBUG_BFIN_HWTRACE_ON
	51	bool "Turn on Blackfin's Hardware Trace"
	52	default y
	53	help
	54	All Blackfins include a Trace Unit which stores a history of the last
	55	16 changes in program flow taken by the program sequencer. The history
	56	allows the user to recreate the program sequencer’s recent path. This
	57	can be handy when an application dies - we print out the execution
	58	path of how it got to the offending instruction.
	59
	60	By turning this off, you may save a tiny amount of power.
	61
	62	choice
	63	prompt "Omit loop Tracing"
	64	default DEBUG_BFIN_HWTRACE_COMPRESSION_OFF
65	depends on DEBUG_BFIN_HWTRACE_ON
66	help
67	The trace buffer can be configured to omit recording of changes in
68	program flow that match either the last entry or one of the last
69	two entries. Omitting one of these entries from the record prevents
70	the trace buffer from overflowing because of any sort of loop (for, do
71	while, etc) in the program.
72
73	Because zero-overhead Hardware loops are not recorded in the trace buffer,
74	this feature can be used to prevent trace overflow from loops that
75	are nested four deep.
76
77	config DEBUG_BFIN_HWTRACE_COMPRESSION_OFF
78	bool "Trace all Loops"
79	help
80	The trace buffer records all changes of flow
81
82	config DEBUG_BFIN_HWTRACE_COMPRESSION_ONE
83	bool "Compress single-level loops"
84	help
85	The trace buffer does not record single loops - helpful if trace
86	is spinning on a while or do loop.
87
88	config DEBUG_BFIN_HWTRACE_COMPRESSION_TWO
89	bool "Compress two-level loops"
90	help
91	The trace buffer does not record loops two levels deep. Helpful if
92	the trace is spinning in a nested loop
93
94	endchoice
95
96	config DEBUG_BFIN_HWTRACE_COMPRESSION
97	int
98	depends on DEBUG_BFIN_HWTRACE_ON
99	default 0 if DEBUG_BFIN_HWTRACE_COMPRESSION_OFF
100	default 1 if DEBUG_BFIN_HWTRACE_COMPRESSION_ONE
101	default 2 if DEBUG_BFIN_HWTRACE_COMPRESSION_TWO
102
103
104	config DEBUG_BFIN_HWTRACE_EXPAND
105	bool "Expand Trace Buffer greater than 16 entries"
106	depends on DEBUG_BFIN_HWTRACE_ON
107	default n
108	help
109	By selecting this option, every time the 16 hardware entries in
110	the Blackfin's HW Trace buffer are full, the kernel will move them
111	into a software buffer, for dumping when there is an issue. This
112	has a great impact on performance, (an interrupt every 16 change of
113	flows) and should normally be turned off, except in those nasty
114	debugging sessions
115
116	config DEBUG_BFIN_HWTRACE_EXPAND_LEN
117	int "Size of Trace buffer (in power of 2k)"
118	range 0 4
119	depends on DEBUG_BFIN_HWTRACE_EXPAND
120	default 1
121	help
122	This sets the size of the software buffer that the trace information
123	is kept in.
124	0 for (2^0) 1k, or 256 entries,
125	1 for (2^1) 2k, or 512 entries,
126	2 for (2^2) 4k, or 1024 entries,
127	3 for (2^3) 8k, or 2048 entries,
128	4 for (2^4) 16k, or 4096 entries
129
130	config DEBUG_BFIN_NO_KERN_HWTRACE
131	bool "Trace user apps (turn off hwtrace in kernel)"
132	depends on DEBUG_BFIN_HWTRACE_ON
133	default n
134	help
135	Some pieces of the kernel contain a lot of flow changes which can
136	quickly fill up the hardware trace buffer. When debugging crashes,
137	the hardware trace may indicate that the problem lies in kernel
138	space when in reality an application is buggy.
139
140	Say Y here to disable hardware tracing in some known "jumpy" pieces
141	of code so that the trace buffer will extend further back.
142
143	config EARLY_PRINTK
144	bool "Early printk"
145	default n
146	help
147	This option enables special console drivers which allow the kernel
148	to print messages very early in the bootup process.
149
150	This is useful for kernel debugging when your machine crashes very
151	early before the console code is initialized. After enabling this
152	feature, you must add "earlyprintk=serial,uart0,57600" to the
153	command line (bootargs). It is safe to say Y here in all cases, as
154	all of this lives in the init section and is thrown away after the
155	kernel boots completely.
156
157	config DUAL_CORE_TEST_MODULE
158	tristate "Dual Core Test Module"
159	depends on (BF561)
160	default n
161	help
162	Say Y here to build-in dual core test module for dual core test.
163
164	config CPLB_INFO
165	bool "Display the CPLB information"
166	help
167	Display the CPLB information.
168
169	config ACCESS_CHECK
170	bool "Check the user pointer address"
171	default y
172	help
173	Usually the pointer transfer from user space is checked to see if its
174	address is in the kernel space.
175
176	Say N here to disable that check to improve the performance.
177
178	endmenu