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authorAndrew Waterman <andrew@sifive.com>2017-06-03 15:36:55 -0700
committerAndrew Waterman <andrew@sifive.com>2017-06-03 15:36:55 -0700
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tree046937c0c4992680be54b528280d45193dba4656 /src/supervisor.tex
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Incorporate Allen's feedback
Diffstat (limited to 'src/supervisor.tex')
-rw-r--r--src/supervisor.tex10
1 files changed, 6 insertions, 4 deletions
diff --git a/src/supervisor.tex b/src/supervisor.tex
index 26073cc..dfcfa85 100644
--- a/src/supervisor.tex
+++ b/src/supervisor.tex
@@ -281,8 +281,9 @@ requiring up to $4\times$XLEN-byte alignment.
\begin{commentary}
When vectored interrupts are enabled, interrupt cause 0, which corresponds to
user-mode software interrupts, are vectored to the same location as
-synchronous exceptions. This ambiguity does not arise in practice, since
-user-mode software interrupts are either disabled or delegated to user mode.
+synchronous exceptions. This ambiguity does not arise in practice for
+supervisor software, since user-mode software interrupts are either disabled
+or delegated to user mode.
\end{commentary}
\subsection{Supervisor Interrupt Registers ({\tt sip} and {\tt sie})}
@@ -561,6 +562,7 @@ Otherwise, {\tt scause} is never written by the implementation, though it may be
explicitly written by software.
The Interrupt bit in the {\tt scause} register is set if the
+trap was caused by an interrupt. The Exception Code field
contains a code identifying the last exception. Table~\ref{scauses}
lists the possible exception codes for the current supervisor ISAs, in
descending order of priority. The Exception Code is an \wlrl\ field,
@@ -895,8 +897,8 @@ writes and the address translation hardware.
\end{commentary}
\begin{commentary}
-Note the instruction has no effect on the translations of other RISC-V
-threads, which must be notified separately. One approach is to use 1)
+Note the instruction has no effect on the translations of other harts,
+which must be notified separately. One approach is to use 1)
a local data fence to ensure local writes are visible globally, then
2) an interprocessor interrupt to the other thread, then 3) a local
SFENCE.VMA in the interrupt handler of the remote thread, and finally