jay_chen wrote: > Hello, all~~~ > > I am using a MCP8548 board with 2.6.14.5 kernel. > And I would like to upgrade memory from 512MB to 2048MB. > Finally, I realize this is not so easy as I think. I encounter several > problems. :~~
Well, it should be easy if you use highmem... > First, I change mem=512M to mem=2048M. > > 1. vmalloc fail problem Are you saying you have vmalloc failures if you don't do any of the below, and enable highmem, with 2GB RAM? Could you provide more details? > So, I change kernel config in "advanced setup" > Change "Set maximum low memory" from 0x30000000 to 0x80000000. > Change "Virtual address of kernel base" from 0xC0000000 to 0x60000000. > Change "Set custom user task size" from 0x80000000 to 0x60000000 > > Someone said that he could change "Virtual address of kernel base" to > 0xA0000000 without problem. > Could I change it to 0x60000000? Any possible problem? There are always *possible* problems. :-) In theory it should work, but it's not a very well tread path. > In adjust_total_lowmem(), fsl_booke_mmu.c > It always limits the low memory to 768MB. (no matter we set mem=768MB or > mem=1024MB, or mem=2048MB) > __max_low_memory = max_low_mem = __cam0 + __cam1 + __cam2; (each TLB could > map up to 256MB) > > My question is could I use more than 3 TLBs here? Such as 8 TLBs to map 2G > ram? Yes. > Or could I use e500v2 new feature, that is 1 TLB could map up to 4G? Yes. -Scott _______________________________________________ Linuxppc-embedded mailing list Linuxppc-embedded@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-embedded
