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| author | Andrew Waterman <andrew@sifive.com> | 2019-03-15 12:39:37 -0700 |
|---|---|---|
| committer | Andrew Waterman <andrew@sifive.com> | 2019-03-15 12:40:41 -0700 |
| commit | eb86f4f0d01381eb6cd520d495450c1ac4670f96 (patch) | |
| tree | 7cf503fea94a08678888e7dda799a9ccb4504d91 | |
| parent | c8c3a436efabcc050738c8fa7414620f6637578a (diff) | |
| download | riscv-isa-manual-eb86f4f0d01381eb6cd520d495450c1ac4670f96.zip riscv-isa-manual-eb86f4f0d01381eb6cd520d495450c1ac4670f96.tar.gz riscv-isa-manual-eb86f4f0d01381eb6cd520d495450c1ac4670f96.tar.bz2 | |
Add more MXR/SUM commentary
| -rw-r--r-- | src/machine.tex | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/src/machine.tex b/src/machine.tex index d202e97..eb8b15e 100644 --- a/src/machine.tex +++ b/src/machine.tex @@ -678,6 +678,12 @@ Note that, while SUM is ordinarily ignored when not executing in S-mode, it {\em is} in effect when MPRV=1 and MPP=S. SUM is hardwired to 0 if S-mode is not supported. +\begin{commentary} +The MXR and SUM mechanisms only affect the interpretation of permissions +encoded in page-table entries. In particular, they have no impact on whether +access exceptions are raised due to PMAs or PMP. +\end{commentary} + \subsubsection{Virtualization Support in {\tt mstatus} Register} \label{virt-control} |