ppc4xx: Add "ecctest" command to test/simulate ECC errors

This patch adds the "ecctest" command to test and simulate ECC errors
(single bit and/or double bit) while running from SDRAM. Currently only
the IBM DDR2 controller is supported (405EX, 440SP(e), 460EX/GT).

This is done by copying and calling functions, modifying the SDRAM
controller operation mode, in internal SRAM/OCM.

For correctable ECC errors (single bit) only the status will be printed
since the DDR2 controller doesn't provide the faulting address:

=> ecctest 1000000 1
Using address 01000000 for 1 bit ECC error injection
ECC: Correctable error

Uncorrectable ECC errors (double bit) will also display the faulting
address:

=> ecctest 1000000 2
Using address 01000000 for 2 bit ECC error injection
ECC: Uncorrectable error at 0x0001000000

To enable this "ecctest" function you need to define CONFIG_CMD_ECCTEST
in the board config header.

Tested on katmai and t3corp.

Signed-off-by: Stefan Roese <sr@denx.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/powerpc/cpu/ppc4xx/Makefile b/arch/powerpc/cpu/ppc4xx/Makefile
index 88d53fb..c9c1a33 100644
--- a/arch/powerpc/cpu/ppc4xx/Makefile
+++ b/arch/powerpc/cpu/ppc4xx/Makefile
@@ -51,6 +51,9 @@ COBJS	+= cpu_init.o
 COBJS	+= denali_data_eye.o
 COBJS	+= denali_spd_ddr2.o
 COBJS	+= ecc.o
+ifdef CONFIG_CMD_ECCTEST
+COBJS	+= cmd_ecctest.o
+endif
 COBJS	+= fdt.o
 COBJS	+= interrupts.o
 COBJS	+= iop480_uart.o