Stuart Wood wrote: > Wolfgamg > > >> What has the MMU to do with it? >> >> Just program your memory controller such that the 4 banks form a >> contiguous region. > > The memory controller unfortunatly can not map the SDRAM banks as > contiguous region. That IS the main problem. For the SDRAM I'm using > It ends up giving me region sizes of 8MBytes. > > U-Boot runs in the first region, and we down load into the second region. > If the down load is larger than the region size it gets corrupted.
IOW, your hardware sucks. Not the first time *that* has happened. > So the thought is to enable the MMU to do the address translation. > Or is there another way to handle this? No. Wait, there is half a way. If your SDRAM banks are not fully decoded (and they most likely are *not*), if you use the address last "copy" of the first bank and the first "copy" of the second bank, you will have two bank's worth of contiguous memory. > It appears to happen when the image size becomes larger then a bank of >> SDRAM. I've got a 32 MByte SDRAM >> that appears as 4 banks of 8 MBytes. >> >> The system is using u-boot 1.1.3 and we will move to 1.3.3 soon. >> The memory regions are broken up like this. >> >> 0xE0000000 - 0xE07FFFFF >> 0xE1000000 - 0xE17FFFFF >> 0xE4000000 - 0xE47FFFFF >> 0xE5000000 - 0xE57FFFFF So you should be able to use 0xE0800000..0xE0FFFFFF - 2nd "copy" of the first bank 0xE1000000..0xE17FFFFF - 1st "copy" of the second bank you will double your available consecutive memory. You can do the same thing with the third and fourth banks of memory, but you will still have a gap between the first pair and second pair. This will reduce your four fragments / three holes to two fragments / one hole. Solved half your problem anyway. 0xE4800000..0xE4FFFFFF - 2nd "copy" of the first bank 0xE5000000..0xE57FFFFF - 1st "copy" of the second bank HTH, gvb ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ U-Boot-Users mailing list U-Boot-Users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/u-boot-users
