Author: rminnich Date: 2008-04-30 06:12:56 +0200 (Wed, 30 Apr 2008) New Revision: 671 Modified: coreboot-v3/northbridge/amd/geodelx/raminit.c Log: Rework Geode LX RAMinit DIMM size formula to be more understandable. Added benefit is complaining loudly for unsupported 2 GB DIMM size. Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net> Tested on the dbe62 up to and including Etherboot. Acked-by: Ronald G. Minnich <rminnich@gmail.com> Modified: coreboot-v3/northbridge/amd/geodelx/raminit.c =================================================================== --- coreboot-v3/northbridge/amd/geodelx/raminit.c 2008-04-29 11:49:42 UTC (rev 670) +++ coreboot-v3/northbridge/amd/geodelx/raminit.c 2008-04-30 04:12:56 UTC (rev 671) @@ -151,16 +151,12 @@ banner(BIOS_DEBUG, "SPDBANKDENSITY"); dimm_size = spd_read_byte(dimm, SPD_BANK_DENSITY); - /* Align so 1 GB (bit 0) is bit 8. This is a little weird to get gcc - * to not optimize this out. - */ - dimm_size |= (dimm_size << 8); + /* Bits 0-1 have been redefined by JEDEC to contain what would have + * been in non-existing bits 8 (1GB) and 9 (2GB). Move bits 0-1 to + * bits 8-9 and mask bits 0-1 off. + */ + dimm_size = ((dimm_size & 0x3) << 8) | (dimm_size & ~0x3); - /* And off 2 GB DIMM size: not supported and the 1 GB size we just - * moved up to bit 8 as well as all the extra on top. - */ - dimm_size &= 0x01FC; - /* Module Density * Module Banks */ /* Shift to multiply by the number of DIMM banks. */ dimm_size <<= (dimm_setting >> CF07_UPPER_D0_MB_SHIFT) & 1;