On Tue, Jun 11, 2013 at 10:30:48AM +0300, Peter De Schrijver wrote: > On Mon, Jun 10, 2013 at 09:55:12PM +0200, Thierry Reding wrote: > > * PGP Signed by an unknown key > > > > On Wed, Jun 05, 2013 at 12:27:31AM +0530, Jay Agarwal wrote: > > [...] > > > @@ -29,7 +29,7 @@ > > > ranges = <0x82000000 0 0x00000000 0x00000000 0 0x00001000 /* port 0 configuration space */ > > > 0x82000000 0 0x00001000 0x00001000 0 0x00001000 /* port 1 configuration space */ > > > 0x82000000 0 0x00004000 0x00004000 0 0x00001000 /* port 2 configuration space */ > > > - 0x81000000 0 0 0x02000000 0 0x00010000 /* downstream I/O */ > > > + 0x81000000 0 0 0x02000000 0 0x00100000 /* downstream I/O */ > > > 0x82000000 0 0x20000000 0x20000000 0 0x10000000 /* non-prefetchable memory */ > > > 0xc2000000 0 0x30000000 0x30000000 0 0x10000000>; /* prefetchable memory */ > > > > That increases the I/O region size from 64 KiB to 1 MiB. Why is that > > necessary? I/O operations can only address 64 KiB, so I don't think > > adding more makes any sense. > > At least PCI allows 32bit I/O addresses. No idea if anyone uses them though. I just realized that we are constrained to 64 KiB by the implementation of pci_ioremap_io(), which assumes each mapping is 64 KiB. Not that it couldn't be changed, but unless there actually is a use-case where more than 64 KiB are required I don't think we should worry about it. Thierry
Attachment:
pgp2TPXo3sk7W.pgp
Description: PGP signature