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| author | Anup Patel | 2020-02-02 14:42:16 +0100 |
|---|---|---|
| committer | Palmer Dabbelt | 2020-02-27 22:46:36 +0100 |
| commit | c695724868ce4049fd79c5a509880dbdf171e744 (patch) | |
| tree | e399f75e9a1aeb4f9c64dfa9a5e985413d5e8d24 /include/hw | |
| parent | riscv: virt: Allow PCI address 0 (diff) | |
| download | qemu-c695724868ce4049fd79c5a509880dbdf171e744.tar.gz qemu-c695724868ce4049fd79c5a509880dbdf171e744.tar.xz qemu-c695724868ce4049fd79c5a509880dbdf171e744.zip | |
target/riscv: Emulate TIME CSRs for privileged mode
Currently, TIME CSRs are emulated only for user-only mode. This
patch add TIME CSRs emulation for privileged mode.
For privileged mode, the TIME CSRs will return value provided
by rdtime callback which is registered by QEMU machine/platform
emulation (i.e. CLINT emulation). If rdtime callback is not
available then the monitor (i.e. OpenSBI) will trap-n-emulate
TIME CSRs in software.
We see 25+% performance improvement in hackbench numbers when
TIME CSRs are not trap-n-emulated.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Diffstat (limited to 'include/hw')
0 files changed, 0 insertions, 0 deletions