SDRAM contents corrupted

[osresearch]

The refresh might not be doing the right thing - after sitting all night the SDRAM contents had a few bit errors compared to what was loaded into it. For example:

29969c29969
< 00075100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
---
> 00075100: ff ff ff ff ff ff ff ff ff ff bf ff ff ff ff ff  ................
44677c44677
< 000ae840: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
---
> 000ae840: ff ff ff ff ff ff ff ff ff ff fe ff ff ff ff ff  ................
50487c50487
< 000c5360: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
---
> 000c5360: ff ff ff ff fd ff ff ff ff ff ff ff ff ff ff ff  ................
52533c52533
< 000cd340: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
---
> 000cd340: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff fe  ................
86337c86337
< 00151400: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................
---
> 00151400: ff ff ff ff ff ff ff f7 ff ff ff ff ff ff ff ff  ................
93746c93746
< 0016e310: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff  ................