From: lkcl <lkcl@web>
Date: Tue, 25 Jun 2019 07:08:10 +0000 (+0100)
Subject: (no commit message)
X-Git-Tag: convert-csv-opcode-to-binary~4470
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=83d01a08be358475466d62541566e93ff2bdab9a;p=libreriscv.git

---

diff --git a/simple_v_extension/sv_prefix_proposal.rst b/simple_v_extension/sv_prefix_proposal.rst
index b5c2cb07c..07c7fa93d 100644
--- a/simple_v_extension/sv_prefix_proposal.rst
+++ b/simple_v_extension/sv_prefix_proposal.rst
@@ -824,6 +824,15 @@ executing 48/64-bit instructions. For just SVPrefix, I would say that the only
 user-visible CSR needed is VL. This is ignoring all the state for
 context-switching and exception handling.
 
+> the consequence of that would be that P48/64 would need
+> its own CSR State to track the subelement index.
+> or that any exceptions would need to occur on a group
+> basis, which is less than ideal,
+> and interrupts would have to be stalled.
+> interacting with SUBVL and requiring P48/64 to save the
+> STATE CSR if needed is a workable compromise that
+> does not result in huge CSR proliferation
+
 --
 
 What are the interaction rules when a 48/64 prefix opcode has a rd/rs