From adc597e5068d28dfc24093c310678188d859ea5f Mon Sep 17 00:00:00 2001
From: "cornelia.huck" <cornelia.huck@0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652>
Date: Thu, 12 Dec 2013 10:08:47 +0000
Subject: ccw: clarify passing of subchannel id

Make clear that the upper half of the register must be ignored, just
like normal I/O instructions do.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

git-svn-id: https://tools.oasis-open.org/version-control/svn/virtio@172 0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652
---
 content.tex | 4 ++++
 1 file changed, 4 insertions(+)

(limited to 'content.tex')

diff --git a/content.tex b/content.tex
index b0a0ab7..b6092b6 100644
--- a/content.tex
+++ b/content.tex
@@ -2243,6 +2243,10 @@ GPR  &   Input Value     & Output Value \\
 \hline
 \end{tabular}
 
+The device MUST ignore bits 0-31 (counting from the left) of GPR2.
+This aligns passing the subchannel ID with the way it is passed
+for the existing I/O instructions.
+
 Host cookie is an optional per-virtqueue 64 bit value that can be
 used by the hypervisor to speed up the notification execution.
 For each notification, the output value is returned in GPR2 and
-- 
cgit v1.2.3

