On Fri, Mar 02, 2012 at 08:38:05PM +0000, John Baldwin wrote: > Author: jhb > Date: Fri Mar 2 20:38:04 2012 > New Revision: 232403 > URL: http://svn.freebsd.org/changeset/base/232403 > > Log: > - Add a bus_dma tag to each PCI bus that is a child of a Host-PCI bridge. > The tag enforces a single restriction that all DMA transactions must not > cross a 4GB boundary. Note that while this restriction technically only > applies to PCI-express, this change applies it to all PCI devices as it > is simpler to implement that way and errs on the side of caution.
Hrm, wouldn't it have been more appropriate to implement this in the Host-PCI bridges instead? Probably for anything but x86 this would allow to easily distinguish at least between PCI and PCI-Express capable bus hierarchies and would move the PAE workaround to the MD bits to where it belongs. Marius _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
