memc(4) - NetBSD Manual Pages

MEMC(4)             NetBSD/mvme68k Kernel Interfaces Manual            MEMC(4)


NAME

     memc -- MVME162-MVME177 Memory Controller Chip


SYNOPSIS

     memc* at mainbus0


DESCRIPTION

     The memc devices are used on MVME162, MVME167, MVME172 and MVME177 boards
     to manage one or more DRAM modules.

     Depending on the type of DRAM module fitted, the device will either be a
     MEMC040 device or an MCECC device. The former manages a Parity DRAM mod-
     ule while the latter manages an ECC DRAM module.


DIAGNOSTICS

     memc0 at mainbus0.  This is the normal autoconfiguration message indicat-
     ing that the Memory Controller Chip has been found and attached to the
     main processor bus.
     memc0: Correctable error on CPU read access to 0x12345678.  This indi-
     cates that an MCECC memory controller detected and corrected a single bit
     error in one of the DRAM banks. There are a few variations on the message
     where "CPU" can be replaced with "Peripheral Device" or "Scrubber", and
     "read" can be substituted for "write".  This message is followed by some
     more details which can help pin-point the error...
     memc0: ECC Syndrome 0x23 (DRAM Bank C, Bit#16).  Pin-points exactly where
     the error occurred.
     memc0: Uncorrectable error on CPU read access to 0x12345678.  Errors like
     this have the potential to corrupt data. As such, it is likely the system
     will panic very soon afterwards.


SEE ALSO

     mvme68k/mainbus(4)


BUGS

     The memc driver does not yet fully support the MEMC040 (Parity) version
     of the device.

NetBSD 9.3                     February 17, 2017                    NetBSD 9.3