On 07/31/2013 04:20 PM, Sergei Shtylyov wrote: > On 08/01/2013 02:06 AM, Stephen Warren wrote: ... >>> That's really horrible design. >> >> Yup. Both USB PHY and EHCI controller registers really are interleaved >> in one range. > > But the standard EHCI register space has no holes IIRC, so they can't > be really that much interleaved as you're describing (unless you have > some non-standard registers of course)... Yes, there are certainly non-standard registers. ... >>> Don't they cause numerous resource conflicts while device nodes >>> being >>> instantiated as the platform devices? > >> No; the driver knows that the HW is screwy and there's lots of >> register-range sharing going on, so it simply maps the registers, rather >> than reserving the physical address range and mapping it. > > Yes, it's clear that the driver should take special measures, I was > asking about the platform device creation phase. What do you see in > /proc/iomem? The drivers don't request the memory region since doing so would cause conflicts. Hence, the regions don't show up in /proc/iomem. This actually isn't that uncommon for DT-based drivers anyway; many use e.g. of_iomap() which IIRC just looks up the resource and maps it without registering the usage. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
