mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-21 02:33:07 +00:00
47e8bc8467
Update the README for DDR ECC, change the name to README.mpc83xx.ddrecc. Signed-off-by: Dave Liu <daveliu@freescale.com> Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
154 lines
4.5 KiB
Text
154 lines
4.5 KiB
Text
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).
|