[PING*2][PATCH] Extend mode-switching to support toggle (1/2)

[Oleg Endo]

On Mon, 2014-05-12 at 13:51 +0100, Joern Rennecke wrote:
> On 12 May 2014 13:16, Christian Bruel <christian.bruel@st.com> wrote:
> 
> > Just for my curiosity, which other targets have multi-way toggling
> > support ?
> 
> The epiphany has, sort of: you read a control register, AND and/or OR
> some mask(s) to the value,
> and write it back.
> If we knew the previous mode, we might elide and AND or an OR.
> 
> I think this is actually quite a common issue.

This is the same as changing/setting the FP modes (PR, SZ) on SH while
preserving the other FPSCR bits, or did I miss something?

Cheers,
Oleg