[U-Boot] [PATCH 1/6] ARM: add secure monitor handler to switch to non-secure state

[Albert ARIBAUD]

Hi Peter,

(sorry for the duplicate; first reply sent was missing recipients, and
I had a fix to do anyway)

On Thu, 23 May 2013 14:00:17 +0100, Peter Maydell
<peter.maydell at linaro.org> wrote:

> On 23 May 2013 13:34, Albert ARIBAUD <albert.u.boot at aribaud.net> wrote:
> > Well -- if you form the acronym, you do end with 'A R M' indeed, but
> > this is quite unfortunate, as 'ARM ARM' is redundant (as the acronym's
> > A already has ARM in it), confusion (as 'ARM' already bears a quite
> > established meaning) and ambiguous (as there are actually several
> > documents with the title of 'ARM<vXXX> Reference Manual' and which
> > would end up with the same acronym).
> 
> "ARM ARM" is the standard abbreviated way of referring to the
> ARM Architecture Reference Manual (and as you can see it's
> not a redundant acronym, since the A doesn't stand for ARM).

Before answering about the double 'ARM', I did google for possible
meanings of the acronym 'ARM' and did not find any indication of it
meaning 'Architecture Reference Manual' except on www.all-acronyms.com,
which is completely foreign to the embedded world and where the
definition is not backed by any substantial source.

OTOH, the ARM Information Center does not use the acronym ARM to mean
'Architecture Reference Manual', nor does the Glossary section of ARM
documents I've read so far - including "the" ARM Glossary (AEG0014E),
which lists quite a lot of 'ARM something' but no 'ARM' alone, except
in the preamble phrase: 'Where the term ARM is used it means “ARM
or any of its subsidiaries as appropriate”'.

Of course, I might have missed it, so any actual pointer to the
definition is heartily welcome.

> A TRM (Technical Reference Manual) is a completely different
> document type, describing a specific processor. Andre is correct
> that the restriction in question is architectural (and thus
> described in the ARM ARM), not implementation specific (which
> would be what you'd find in a TRM).

You are correct that here the document is not a TRM.

> > So if you don't want to use 'TRM' (which I can understand), then
> > at least please replace 'ARM ARM' with 'ARMv7-AR Reference Manual'.
> > Stating the DDI* reference is not a must, unless you want to specify
> > a given revision (but then I suggest adding it after 'Manual' too).
> 
> "ARMv7-AR Reference Manual" is confusing, because you've dropped
> the "Architecture" bit.

That drop was involuntary.

> Since this is only a git comment, I'd suggest "ARM architecture
> reference manual" as both clear for non-ARM people and sufficiently
> unambiguous, or "ARMv7-AR Architecture Reference Manual" if you
> want to be a bit more formal about it.

Since a git comment is there for a reason, which includes helping its
readers understand the commit, I consider "ARMv7-AR Reference Manual"
to help them much more than 'ARM ARM', as it points them unambiguously
to the document by stating the exact title under which it is listed in
the ARM information center, but I am ok with 'ARMv7-AR Architecture
Reference Manual' as this how its title goes.

> thanks
> -- PMM

Amicalement,
-- 
Albert.