Piteball
/
android_kernel_samsung_msm8976
mirror of https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git
1
1
Fork 0
Code Issues Projects Releases Wiki Activity

parisc: document the shadow registers 

commit a83f58bcb24003b9de2364de7c829a263423ead7 upstream.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Helge Deller 2013-06-29 13:24:16 +02:00 committed by Greg Kroah-Hartman
parent b6891ed4e6
commit fa8223db1d
1 changed files with 8 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
Documentation/parisc/registers
View File

@ -77,6 +77,14 @@ PSW default E value 0
Shadow Registers used by interruption handler code
TOC enable bit 1
=========================================================================
The PA-RISC architecture defines 7 registers as "shadow registers".
Those are used in RETURN FROM INTERRUPTION AND RESTORE instruction to reduce
the state save and restore time by eliminating the need for general register
(GR) saves and restores in interruption handlers.
Shadow registers are the GRs 1, 8, 9, 16, 17, 24, and 25.
=========================================================================
Register usage notes, originally from John Marvin, with some additional
notes from Randolph Chung.