On Thu, Oct 10, 2024 at 06:40:48PM -0400, Frank Li wrote: > On Thu, Oct 10, 2024 at 04:57:45PM -0500, Bjorn Helgaas wrote: > > On Tue, Oct 08, 2024 at 03:53:58PM -0400, Frank Li wrote: > > > Introduce field 'parent_bus_addr' in of_pci_range to retrieve untranslated > > > CPU address information. > It is "untranslated CPU address", previous patch use cpu_untranslate_addr. > Rob suggest change to parent_bus_addr. > > Is it better change to "to retrieve the address at bus fabric port" instead > of *untranslated* CPU address "parent_bus_addr" will hold an untranslated CPU address in some cases, but not all. I think it's better to use a generic term like "parent bus addres" here because that is accurate in all cases. > > and this "ranges": > > > > ranges = <0x5f000000 0x0 0x5f000000 0x21000000>, > > <0x80000000 0x0 0x70000000 0x10000000>; > > > > means: > > > > (IA 0x5f000000, CPU 0x0 0x5f000000, length 0x21000000) > > (IA 0x80000000, CPU 0x0 0x70000000, length 0x10000000) > > > > which would mean: > > > > CPU 0x0_5f000000-0x0_7fffffff -> IA 0x5f000000-0x7fffffff > > CPU 0x0_70000000-0x0_7fffffff -> IA 0x80000000-0x8fffffff > > Yes, > > > I must be misunderstanding something because this would mean CPU addr > > 0x70000000 would translate to IA addr 0x70000000 via the first range > > and to IA addr 0x80000000 via the second range, which doesn't make > > sense. > > Yes, it is my mistake, first length should reduce to 0x0100_0000 from > 0x21000000. It works because dt convert IA to CPU, instead of CPU to > IA. for example, input IA: 0x80000000, match second one, convert to > CPU address 0x0_70000000. Great, if we can omit 0x5f000000 completely that will avoid the confusion. I hope the actual DT doesn't have this error. Bjorn
