How to enable ddr's ecc in Linux?

Question

I'm using linux on powerpc p1020,and Freescale provides a whole system include u-boot,linux.The system does not enable ecc check by default.I'm trying to enable this function by modify p1020's ddr_sdram_cfg register,but I failed.In linux,I could only mmap register's memory space with PROT_READ permissions and makes linux outage if add PROT_WRITE permissions.Then I try to enable ecc in u-boot,but I failed too,the u-boot stops if I use mw to modify ddr_sdram_cfg. Could anybody meet this problem?Thanks anyone help me.

Answer 1

The answer will depend on your target platform, for example you may have P1020RDB, or something else.

Assuming that SDRAM ECC can be enabled on the platform (this may include extra RAM to hold syndrome bits, e.g. 36-bit data path) then ECC needs to be enabled at the time that SDRAM controller is initialized. It can't be turned on at runtime while the SDRAM is already in use. Thorough study of chip reference manual, target platform documentation, and (ideally) target BSP u-boot source will reveal everything that's needed.