Board:via/epia

Current problems

• Mixing of memory widths appears to cause memory errors. The 256MB and 64MB DIMM from the table below show memory errors when installed together. Or maybe it's the width itself, since all the 8-bit-wide ones work.
• shutting down system does not turn off power.
• Hangs at ram detection. Patch which improves this but does not solve available 2007-06-04
• If the via_agp module is loaded, the machine resets. This can be worked around by blacklisting that kernel module. It may also be necessary to blacklist agpgart.

Previous problems

• MA map type is set incorrectly for some types of DIMM. Fixed as of r2653.

MA Map Types

The values for MA map type refer to bits 15-13, 7-5, and 3-1 of offset 0x59-0x58 of the VT8601A host bridge. See the VT8601/PLE133 data sheet for details. All values other than 0xx and 100 are documented as "reserved (do not program)"

Values determined by testing various modules with the factory BIOS.

DIMM size	Row Density (SPD 31)	Width (SPD 13)	Rows(SPD 5)	MA map type	Works
512MB	256MB	8	2	0xe (111)	Yes (benh)
256MB	128MB	16	2	0xc (110)	No (hawke)
128MB	128MB	16	1	0xc (110)	No (hawke)
128MB	64MB	8	2	0x8 (100)	Yes (benh)
64MB	64MB	8	1	0x8 (100)	Yes (hawke)

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