#11085 BLOC 1.5-har: XO-1.75 Memory errors
Zarro Boogs per Child
bugtracker at laptop.org
Thu Sep 1 23:43:10 EDT 2011
#11085: XO-1.75 Memory errors
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Reporter: wad | Owner: wad
Type: defect | Status: assigned
Priority: blocker | Milestone: 1.5-hardware-C
Component: ofw - open firmware | Version: 1.75-B1
Resolution: | Keywords: XO-1.75, memory
Next_action: reproduce | Verified: 0
Deployment_affected: | Blockedby:
Blocking: |
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Comment(by wad):
Q4B07re restored the default DQ/Addr drive settings to those use before
Q4B05, and also changed the default PHY_RFIFO_PTR_DLY_VAL and DQ_EXT_DLY
to 3/3. These had been 4/4 since Q4B05.
After a 48 hour run on 30+ laptops (additional laptops ran for less than
48 hrs), three seg faults were seen. Two (on laptops which had seen
memory errors in other close to stable configurations) generated no log
entries, other than memtester stopping due to segfault. The third
generated a strange error message (#11204), but also stopped memtester due
to a seg fault.
Playing around with other values of PHY_RFIFO_PTR_DLY_VAL and DQ_EXT_DLY
resulted in the following observation: No values lower than 3/3 work.
3/2 fails, as does 3/1, 2/2, etc. 5/5 seems to work fine, and will be
tested further.
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Ticket URL: <http://dev.laptop.org/ticket/11085#comment:15>
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