RE: [PATCH 1/5 v2] Add the explanation and a sample of RapidIO DTS sector to the document of booting-without-of.txt file.

Hi, Segher,=20

DTS sector to the document of booting-without-of.txt file.
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+    - #address-cells : Address representation for

"rapidio" devices.

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+      This field represents the number of cells needed=20

to represent

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+      the RapidIO address of the registers.  For

supporting more than

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+      32-bits RapidIO address, this field should be <2>.
+      See 1) above for more details on defining #address-cells.

What does the RapidIO standard say about number of address
bits?  You want to follow that, so all RapidIO devices can
use the same #address-cells, not just the FSL ones.  Also,
are there different kinds of address spaces on the bus, or
is it just one big memory-like space?

I've checked the specification of RapidIO. The supporting of RapidIO
extended address modes are 66, 50 and 34 bit.

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These three are all two bits more than some "regular" size --
do those two extra bits have some special meaning perhaps,
like an address space identifier or something?
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The Freescale's silicons is only support 34 bit address now.
Do you mean I should not use words -- 'should be <2>'?
The #address-cells should be assigned according the address mode
supported by silicon.

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No.  The #address-cells is determined by the bus binding,
so that all RapidIO busses on the planet can be represented
in a similar way in the OF device tree.  Take for example
the PCI binding, which gives you three address cells -- one
to distinguish between different address spaces (configuration
space, legacy I/O space, memory mapped space) and to contain
some flags (prefetchable vs. non-prefetchable, etc.); the
other two 32-bit cells contain a 64-bit address, although
config and legacy I/O never are more than 32 bit, and many
PCI devices can't do 64-bit addressing at all.
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Now, there is no OF binding for RapidIO yet of course, but
it would be good to start thinking about one while doing
the binding for your specific controller -- it will make
life easier down the line for everyone, including yourself.
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How about I add more words here for more clear expression?
Such as "<2> for 34 and 50 bit address, <3> for 66 bit address".

Thanks!
Wei.