>> I'm also not clear what kind of BIOS quirk it's trying to >> resolve. Is the issue just that PCI setup from Linux, long >> before the HCD initializes, ends up confusing the BIOS >> on those "summit" machines? What symptoms would >> suggest that I should try this option, on non-summit boxes? > >https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=126984 > >Here's the interesting part: > >> The hardware team here narrowed down the boot time hang to a >BIOS bug >> where the USB Legacy support feature causes register >corruption. This >> is unfortunately due to architecture timing constraints and >cannot be >> fixed with a BIOS update. Disabling Legacy USB support works around >> the issue, but leaves the user w/o keyboard support in grub. [snip] >I suspect Aleks hits a similar issue with some other hardware. > >-- Pete >
Pete, thanks for an explanation & reference. Though, I also got "not authorized" while trying to access it. Patch is supposed to resolve at least 2 issues (I ran into both of them on different laptops): 1. USB Legacy support problem Pete mentioned above 2. Boot lockup problem due to an interrupt shared with HC on a platform with legacy free BIOS. Symptoms for second one are described here: http://www.mail-archive.com/[EMAIL PROTECTED]/msg267 77.html Basically, in a case of legacy free BIOS, HC is not in SMM mode, and USB IRQ is routed to PCI IRQ line and generates interrupts. When this IRQ is enabled in PIC (by driver that starts before HC driver), system is flooded with interrupts. One solution is to reset HC, but it takes some time (at least 50ms). I agree that it might duplicate SOME code in HC driver, but HC init executes too late. Well, if handoff has been done early, it might not be necessary to do the same in HC driver. Aleks. ------------------------------------------------------- This SF.Net email is sponsored by BEA Weblogic Workshop FREE Java Enterprise J2EE developer tools! Get your free copy of BEA WebLogic Workshop 8.1 today. http://ads.osdn.com/?ad_idP47&alloc_id808&op=click _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
