Mikulas Patocka writes: > Hi > > This patch fixes a data corruption when SSD is connected to Ultra 5. > > Mikulas > > -- > > Serialize CMD643 and CMD646 to fix a hardware bug with SSD > > CMD646 corrupts data on concurrent transfers on both channels when IDE SSD is > connected to one of the channels. > > Setup that demonstrates this hardware bug: Ultra 5, onboard CMD646, rev 3. > /dev/hda is 8GB Seagate ST38410A in MWDMA2 > /dev/hdd is 32GB SSD SiliconHardDisk in MWDMA2 > > - When reading /dev/hdd (for example with dd or fsck), reads from /dev/hda > are corrupted, there are twiddled single bits 1->0 and some full 32-bit > words corrupted, sometimes commands fail (which switches /dev/hda to > PIO mode but the corruptions happen even in PIO). > - Reads from /dev/hdd don't seem to be corrupted (i.e. fsck passes fine). > - When I connected normal rotating harddisk to /dev/hdd, there was no > corruption, so the corruption is something specific to SSD. > - I tried the same setup on a PCI card with CMD649 and saw no corruption. > > This patch serializes the operation for CMD646 and 643 (I didn't test > CMD643 but it may have the same hw bug too because it's earlier design). > CMD649 is good. I don't know anything about CMD 648. Have you checked if the libata pata_cmd64x driver also has this problem? I know that it works fine on the Ultra 5 with just a single pata drive, but the pata+ssd combo may not have been tested. -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
