[people/ms/u-boot.git] / doc / README.mpc83xx.ddrecc

Overview
========

The overall usage pattern for ECC diagnostic commands is the following:

  * (injecting errors is initially disabled)

  * define inject mask (which tells the DDR controller what type of errors
    we'll be injecting: single/multiple bit etc.)

  * enable injecting errors - from now on the controller injects errors as
    indicated in the inject mask

IMPORTANT NOTICE: enabling injecting multiple-bit errors is potentially
dangerous as such errors are NOT corrected by the controller. Therefore caution
should be taken when enabling the injection of multiple-bit errors: it is only
safe when used on a carefully selected memory area and used under control of
the 'ecc testdw' 'ecc testword' command (see example 'Injecting Multiple-Bit
Errors' below). In particular, when you simply set the multiple-bit errors in
inject mask and enable injection, U-Boot is very likely to hang quickly as the
errors will be injected when it accesses its code, data etc.


Use cases for DDR 'ecc' command:
================================

Before executing particular tests reset target board or clear status registers:

=> ecc captureclear
=> ecc errdetectclr all
=> ecc sbecnt 0


Injecting Single-Bit Errors
---------------------------

1. Set 1 bit in Data Path Error Inject Mask

=> ecc injectdatahi 1

2. Run test over some memory region

=> ecc testdw 200000 10

3. Check ECC status

=> ecc status
...
Memory Data Path Error Injection Mask High/Low: 00000001 00000000
...
Memory Single-Bit Error Management (0..255):
  Single-Bit Error Threshold: 255
  Single Bit Error Counter: 16
...
Memory Error Detect:
  Multiple Memory Errors: 0
  Multiple-Bit Error: 0
  Single-Bit Error: 0
...

16 errors were generated, Single-Bit Error flag was not set as Single Bit Error
Counter did not reach  Single-Bit Error Threshold.

4. Make sure used memory region got re-initialized with 0x0123456789abcdef

=> md 200000
00200000: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200010: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200020: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200030: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200040: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200050: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200060: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200070: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200080: deadbeef deadbeef deadbeef deadbeef    ................
00200090: deadbeef deadbeef deadbeef deadbeef    ................

Injecting Multiple-Bit Errors
-----------------------------

1. Set more than 1 bit in Data Path Error Inject Mask

=> ecc injectdatahi 1
=> ecc injectdatalo 1

2. Run test over some memory region

=> ecc testword 200000 1

3. Check ECC status

=> ecc status
...
Memory Data Path Error Injection Mask High/Low: 00000001 00000001
...
Memory Error Detect:
  Multiple Memory Errors: 0
  Multiple-Bit Error: 1
  Single-Bit Error: 0
...

The Multiple Memory Errors flags not set and Multiple-Bit Error flags are set.

4. Make sure used memory region got re-initialized with 0x0123456789abcdef

=> md 200000
00200000: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200010: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200020: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200030: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200040: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200050: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200060: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200070: 01234567 89abcdef 01234567 89abcdef    .#Eg.....#Eg....
00200080: deadbeef deadbeef deadbeef deadbeef    ................
00200090: deadbeef deadbeef deadbeef deadbeef    ................


Test Single-Bit Error Counter and Threshold
-------------------------------------------

1. Set 1 bit in Data Path Error Inject Mask

=> ecc injectdatahi 1

2. Enable error injection

=> ecc inject en

3. Let u-boot run for a with Single-Bit error injection enabled

4. Disable error injection

=> ecc inject dis

4. Check status

=> ecc status

...
Memory Single-Bit Error Management (0..255):
  Single-Bit Error Threshold: 255
  Single Bit Error Counter: 199

Memory Error Detect:
  Multiple Memory Errors: 1
  Multiple-Bit Error: 0
  Single-Bit Error: 1
...

Observe that Single-Bit Error is 'on' which means that Single-Bit Error Counter
reached Single-Bit Error Threshold. Multiple Memory Errors bit is also 'on', that
is Counter reached Threshold more than one time (it wraps back after reaching
Threshold).
Commit	Line	Data
dc9e499c RJ	1	Overview
	2	========
	3
	4	The overall usage pattern for ECC diagnostic commands is the following:
	5
	6	* (injecting errors is initially disabled)
	7
	8	* define inject mask (which tells the DDR controller what type of errors
	9	we'll be injecting: single/multiple bit etc.)
	10
	11	* enable injecting errors - from now on the controller injects errors as
	12	indicated in the inject mask
	13
	14	IMPORTANT NOTICE: enabling injecting multiple-bit errors is potentially
	15	dangerous as such errors are NOT corrected by the controller. Therefore caution
	16	should be taken when enabling the injection of multiple-bit errors: it is only
	17	safe when used on a carefully selected memory area and used under control of
47e8bc84 DL	18	the 'ecc testdw' 'ecc testword' command (see example 'Injecting Multiple-Bit
	19	Errors' below). In particular, when you simply set the multiple-bit errors in
	20	inject mask and enable injection, U-Boot is very likely to hang quickly as the
	21	errors will be injected when it accesses its code, data etc.
d326f4a2 MB	22
	23
	24	Use cases for DDR 'ecc' command:
	25	================================
	26
	27	Before executing particular tests reset target board or clear status registers:
	28
	29	=> ecc captureclear
	30	=> ecc errdetectclr all
	31	=> ecc sbecnt 0
	32
	33
	34	Injecting Single-Bit Errors
	35	---------------------------
	36
	37	1. Set 1 bit in Data Path Error Inject Mask
	38
	39	=> ecc injectdatahi 1
	40
	41	2. Run test over some memory region
	42
47e8bc84	43	=> ecc testdw 200000 10
d326f4a2 MB	44
	45	3. Check ECC status
	46
	47	=> ecc status
	48	...
	49	Memory Data Path Error Injection Mask High/Low: 00000001 00000000
	50	...
	51	Memory Single-Bit Error Management (0..255):
	52	Single-Bit Error Threshold: 255
	53	Single Bit Error Counter: 16
	54	...
	55	Memory Error Detect:
	56	Multiple Memory Errors: 0
	57	Multiple-Bit Error: 0
	58	Single-Bit Error: 0
	59	...
	60
	61	16 errors were generated, Single-Bit Error flag was not set as Single Bit Error
	62	Counter did not reach Single-Bit Error Threshold.
	63
47e8bc84	64	4. Make sure used memory region got re-initialized with 0x0123456789abcdef
d326f4a2 MB	65
d326f4a2 MB	66	=> md 200000
47e8bc84 DL	67	00200000: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	68	00200010: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	69	00200020: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	70	00200030: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	71	00200040: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	72	00200050: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	73	00200060: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	74	00200070: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
d326f4a2 MB	75	00200080: deadbeef deadbeef deadbeef deadbeef ................
	76	00200090: deadbeef deadbeef deadbeef deadbeef ................
	77
d326f4a2 MB	78	Injecting Multiple-Bit Errors
	79	-----------------------------
	80
	81	1. Set more than 1 bit in Data Path Error Inject Mask
	82
47e8bc84 DL	83	=> ecc injectdatahi 1
47e8bc84 DL	84	=> ecc injectdatalo 1
d326f4a2 MB	85
	86	2. Run test over some memory region
	87
47e8bc84	88	=> ecc testword 200000 1
d326f4a2 MB	89
	90	3. Check ECC status
	91
	92	=> ecc status
	93	...
47e8bc84	94	Memory Data Path Error Injection Mask High/Low: 00000001 00000001
d326f4a2 MB	95	...
d326f4a2 MB	96	Memory Error Detect:
47e8bc84	97	Multiple Memory Errors: 0
d326f4a2 MB	98	Multiple-Bit Error: 1
	99	Single-Bit Error: 0
	100	...
	101
47e8bc84	102	The Multiple Memory Errors flags not set and Multiple-Bit Error flags are set.
d326f4a2	103
47e8bc84	104	4. Make sure used memory region got re-initialized with 0x0123456789abcdef
d326f4a2 MB	105
d326f4a2 MB	106	=> md 200000
47e8bc84 DL	107	00200000: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	108	00200010: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	109	00200020: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	110	00200030: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	111	00200040: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	112	00200050: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	113	00200060: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
	114	00200070: 01234567 89abcdef 01234567 89abcdef .#Eg.....#Eg....
d326f4a2 MB	115	00200080: deadbeef deadbeef deadbeef deadbeef ................
	116	00200090: deadbeef deadbeef deadbeef deadbeef ................
	117
	118
	119	Test Single-Bit Error Counter and Threshold
	120	-------------------------------------------
	121
	122	1. Set 1 bit in Data Path Error Inject Mask
	123
	124	=> ecc injectdatahi 1
	125
	126	2. Enable error injection
	127
	128	=> ecc inject en
	129
	130	3. Let u-boot run for a with Single-Bit error injection enabled
	131
	132	4. Disable error injection
	133
	134	=> ecc inject dis
	135
	136	4. Check status
	137
	138	=> ecc status
	139
	140	...
	141	Memory Single-Bit Error Management (0..255):
	142	Single-Bit Error Threshold: 255
47e8bc84	143	Single Bit Error Counter: 199
d326f4a2 MB	144
	145	Memory Error Detect:
	146	Multiple Memory Errors: 1
	147	Multiple-Bit Error: 0
	148	Single-Bit Error: 1
	149	...
	150
	151	Observe that Single-Bit Error is 'on' which means that Single-Bit Error Counter
	152	reached Single-Bit Error Threshold. Multiple Memory Errors bit is also 'on', that
	153	is Counter reached Threshold more than one time (it wraps back after reaching
	154	Threshold).