17 messages in org.freebsd.freebsd-usb31st address line sometimes not used ...| From | Sent On | Attachments |
|---|---|---|
| Hans Petter Selasky | May 27, 2007 8:35 pm | |
| M. Warner Losh | May 27, 2007 8:55 pm | |
| John-Mark Gurney | May 27, 2007 10:19 pm | |
| Hans Petter Selasky | May 28, 2007 6:43 am | |
| Hans Petter Selasky | May 28, 2007 6:53 am | |
| Hans Petter Selasky | May 28, 2007 7:04 am | |
| Julian Elischer | May 28, 2007 7:15 am | |
| John-Mark Gurney | May 28, 2007 7:50 am | |
| Julian Elischer | May 28, 2007 7:59 am | |
| Hans Petter Selasky | Jun 11, 2007 7:19 am | |
| Julian Elischer | Jun 12, 2007 5:29 pm | |
| Hans Petter Selasky | Jun 13, 2007 9:04 am | |
| Julian Elischer | Jun 15, 2007 7:35 pm | |
| Hans Petter Selasky | Jun 18, 2007 6:26 am | |
| M. Warner Losh | Jun 18, 2007 7:39 pm | |
| Thomas Sparrevohn | Jun 19, 2007 8:49 am | |
| Alexander Leidinger | Jun 19, 2007 12:08 pm |
| Subject: | 31st address line sometimes not used on EHCI/UHCI/OHCI | |
|---|---|---|
| From: | M. Warner Losh (im...@bsdimp.com) | |
| Date: | May 27, 2007 8:55:31 pm | |
| List: | org.freebsd.freebsd-usb | |
In message: <2007...@c2i.net> Hans Petter Selasky <hsel...@c2i.net> writes: : I've got some reports back that some USB host controllers do not support : transferring memory from a location higher than 2GB. : : What should we do about this? : : Should we limit all USB DMA allocations to the lower 2GB of the memory?
busdma should be managing this behind the scenes. You shouldn't care, as the problematical usb controllers, if any, can do the bouncing as required. We need to get the hierarchical bus tagging stuff more fully integrated, then we'd get this for free.
Of course, you'd have to stop using contigmalloc to allocate all the memory for usb. That won't work on some of the embedded platforms we have, for example, because memory on them isn't as fungible as it is on i386 and amd64.
Warner