On Thu, Jan 10, 2013 at 06:26:55PM +0000, Arnd Bergmann wrote: > On Thursday 10 January 2013, Thierry Reding wrote: > > I don't understand how this would help. The encoding is like this: > > > > [27:24] extended register number > > [23:16] bus number > > [15:11] device number > > [10: 8] function number > > [ 7: 0] register number > > > > So it doesn't matter whether I use separate areas per bus or not. As > > soon as the whole extended configuration space needs to be accessed a > > whopping 28 bits (256 MiB) are required. > > > > What you propose would work if only regular configuration space is > > supported. I'm not sure if that's an option. > > I mean something like: > > struct tegra_bus_private { > ... > void __iomem *config_space[16]; > }; > > > void tegra_scan_bus(struct pci_bus *bus) > { > int i; > struct tegra_bus_private *priv = bus->dev->private; > > for (i=0; i<16; i++) > priv->config_space[i] = ioremap(config_space_phys + > 65536 * bus->primary + i * SZ_1M, 65536); > > ... > }
Okay, I see. It's a bit kludgy, but I guess so was the I/O map cache. It'll take some more time to work this out and test, but I'll give it a shot. Thierry
pgpC4AnXiuPs2.pgp
Description: PGP signature