On Thu, Jun 8, 2023 at 5:43 PM Andrew Jones <[email protected]> wrote: > > On Thu, Jun 08, 2023 at 12:23:10AM -0700, Tommy Wu wrote: > > This patchset added support for Smrnmi Extension in RISC-V. > > > > There are four new CSRs and one new instruction added to allow NMI to be > > resumable in RISC-V, which are: > > > > ============================================================= > > * mnscratch (0x740) > > * mnepc (0x741) > > * mncause (0x742) > > * mnstatus (0x744) > > ============================================================= > > * mnret: To return from RNMI interrupt/exception handler. > > ============================================================= > > > > RNMI also has higher priority than any other interrupts or exceptions > > and cannot be disabled by software. > > > > RNMI may be used to route to other devices such as Bus Error Unit or > > Watchdog Timer in the future. > > > > The interrupt/exception trap handler addresses of RNMI are > > implementation defined. > > Is there an M-mode software PoC for this with implemented handlers? > > Thanks, > drew >
Sorry for the late reply. We implement a simple RNMI trap handler in the customized OpenSBI [1], and use the work from Damien Hedde [2] to inject the RNMI interrupt. We can test the RNMI functionality with the signal injection in the customized QEMU [3]. I’ll include the test case in the latest upstream email. [1] https://github.com/TommyWu-fdgkhdkgh/opensbi/commits/dev/twu/master [2] https://lists.gnu.org/archive/html/qemu-devel/2019-06/msg06232.html [3] https://github.com/TommyWu-fdgkhdkgh/qemu/tree/dev/twu/master > > > > Changelog: > > > > v4 > > * Fix some coding style issues. > > ( Thank Daniel for the suggestions. ) > > > > v3 > > * Update to the newest version of Smrnmi extension specification. > > > > v2 > > * split up the series into more commits for convenience of review. > > * add missing rnmi_irqvec and rnmi_excpvec properties to riscv_harts. > > > > Tommy Wu (4): > > target/riscv: Add Smrnmi cpu extension. > > target/riscv: Add Smrnmi CSRs. > > target/riscv: Handle Smrnmi interrupt and exception. > > target/riscv: Add Smrnmi mnret instruction. > > > > hw/riscv/riscv_hart.c | 21 +++++ > > include/hw/riscv/riscv_hart.h | 4 + > > target/riscv/cpu.c | 18 ++++ > > target/riscv/cpu.h | 11 +++ > > target/riscv/cpu_bits.h | 23 ++++++ > > target/riscv/cpu_helper.c | 81 ++++++++++++++++-- > > target/riscv/csr.c | 82 +++++++++++++++++++ > > target/riscv/helper.h | 1 + > > target/riscv/insn32.decode | 3 + > > .../riscv/insn_trans/trans_privileged.c.inc | 12 +++ > > target/riscv/op_helper.c | 49 +++++++++++ > > 11 files changed, 300 insertions(+), 5 deletions(-) > > > > -- > > 2.31.1 > > > >
