aboutsummaryrefslogtreecommitdiff
path: root/src/priv-csrs.tex
diff options
context:
space:
mode:
authorPaolo Bonzini <pbonzini@redhat.com>2019-07-31 09:15:32 +0200
committerAndrew Waterman <andrew@sifive.com>2019-08-16 14:14:12 -0700
commit4bfae7862e436ce67c1aebaf2d95f0d35c658c51 (patch)
tree90ac3a5d6468d635f05e4f862f7e5ab12639fa84 /src/priv-csrs.tex
parent81300f89c4ac5f49b052b42ffe70924218d69a33 (diff)
downloadriscv-isa-manual-4bfae7862e436ce67c1aebaf2d95f0d35c658c51.zip
riscv-isa-manual-4bfae7862e436ce67c1aebaf2d95f0d35c658c51.tar.gz
riscv-isa-manual-4bfae7862e436ce67c1aebaf2d95f0d35c658c51.tar.bz2
hypervisor: add performance counter delta registers
It has been requested that we add htimedelta[h] CSRs so that hosts can lie to guests about the current time, without requiring trapping and emulating. cycle is also included, since the SBI set timer callback has absolute cycles as the argument. There is no intent to add equivalent CSRs for instret and performance counters. Fixes: #298
Diffstat (limited to 'src/priv-csrs.tex')
-rw-r--r--src/priv-csrs.tex5
1 files changed, 5 insertions, 0 deletions
diff --git a/src/priv-csrs.tex b/src/priv-csrs.tex
index fe78bab..166ff06 100644
--- a/src/priv-csrs.tex
+++ b/src/priv-csrs.tex
@@ -241,6 +241,11 @@ Number & Privilege & Name & Description \\
\hline
\tt 0x680 & HRW &\tt hgatp & Hypervisor guest address translation and protection. \\
\hline
+\multicolumn{4}{|c|}{Hypervisor Counter/Timer Virtualization Registers} \\
+\hline
+\tt 0x605 & HRW &\tt htimedelta & Delta for VS/VU-mode timer. \\
+\tt 0x615 & HRW &\tt htimedeltah & Upper 32 bits of {\tt htimedelta}, RV32I only. \\
+\hline
\multicolumn{4}{|c|}{Virtual Supervisor Registers} \\
\hline
\tt 0x200 & HRW &\tt vsstatus & Virtual supervisor status register. \\