Tejun Heo wrote:
Hello, all. During 2.6.24-rc1, libata enabled ATA-ACPI support by default and there have been a lot of regression reports stemming from it. I have patchset ready to fix most of the problems. With these patches applied, libata should be able to cope with most failures pretty well. There is one remaining issue tho. libata caches the result of _GTM during controller for later use. The primary use is to peek at how BIOS configured the controller. Some controllers (pata_via and pata_amd) lack proper cable detection and BIOS configured values are used as reference. This caching is done before any other operation is performed on the port to avoid caching corrupted data. Problem is that _GTM implementation on certain BIOSen crap themselves if invoked on empty channels. However, as written above, because initial _GTM caching is done before any actual operation is performed on the port, libata can't determine whether the port is occupied or not when trying to cache _GTM result. Unfortunately, VIA PATA is on both categories - it needs _GTM caching but can't cope with _GTM invocation on empty ports. Yay!
I seem to have lost the thread/bug report where we decided that one board always choked on an empty channel. Maybe it's not that and it's just another case of the same issue where our resetting default timing values on the controller before calling _GTM would choke the _GTM method?
-- Robert Hancock Saskatoon, SK, Canada To email, remove "nospam" from hancockr@xxxxxxxxxxxxx Home Page: http://www.roberthancock.com/ - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
