Anup Patel <apatel@xxxxxxxxxxxxxxxx> writes: > The RISC-V AIA specification is ratified as-per the RISC-V international > process. The latest ratified AIA specifcation can be found at: > https://github.com/riscv/riscv-aia/releases/download/1.0/riscv-interrupts-1.0.pdf > > At a high-level, the AIA specification adds three things: > 1) AIA CSRs > - Improved local interrupt support > 2) Incoming Message Signaled Interrupt Controller (IMSIC) > - Per-HART MSI controller > - Support MSI virtualization > - Support IPI along with virtualization > 3) Advanced Platform-Level Interrupt Controller (APLIC) > - Wired interrupt controller > - In MSI-mode, converts wired interrupt into MSIs (i.e. MSI generator) > - In Direct-mode, injects external interrupts directly into HARTs > > For an overview of the AIA specification, refer the AIA virtualization > talk at KVM Forum 2022: > https://static.sched.com/hosted_files/kvmforum2022/a1/AIA_Virtualization_in_KVM_RISCV_final.pdf > https://www.youtube.com/watch?v=r071dL8Z0yo > > To test this series, use QEMU v7.2 (or higher) and OpenSBI v1.2 (or higher). > > These patches can also be found in the riscv_aia_v12 branch at: > https://github.com/avpatel/linux.git > > Changes since v11: > - Rebased on Linux-6.8-rc1 > - Included kernel/irq related patches from "genirq, irqchip: Convert ARM > MSI handling to per device MSI domains" series by Thomas. > (PATCH7, PATCH8, PATCH9, PATCH14, PATCH16, PATCH17, PATCH18, PATCH19, > PATCH20, PATCH21, PATCH22, PATCH23, and PATCH32 of > https://lore.kernel.org/linux-arm-kernel/20221121135653.208611233@xxxxxxxxxxxxx/) > - Updated APLIC MSI-mode driver to use the new WIRED_TO_MSI mechanism. > - Updated IMSIC driver to support per-device MSI domains for PCI and > platform devices. Thanks for working on this, Anup! I'm still reviewing the patches. I'm hitting a boot hang in text patching, with this series applied on 6.8-rc2. IPI issues? I'm booting with U-boot UEFI. kernel config: https://gist.github.com/bjoto/bac563e6dcaab68dba1a5eaf675d51aa QEMU 8.2.0/OpenSBI 1.4: | qemu-system-riscv64 \ | -machine virt,acpi=off,aia=aplic-imsic \ | -cpu rv64,v=true,vlen=256,elen=64,h=true,zbkb=on,zbkc=on,zbkx=on,zkr=on,zkt=on,svinval=on,svnapot=on,svpbmt=on \ | -smp 4 \ | -object rng-random,filename=/dev/urandom,id=rng0 \ | -device virtio-rng-device,rng=rng0 \ | -append "root=/dev/vda2 rw earlycon console=tty0 console=ttyS0 panic=-1 oops=panic sysctl.vm.panic_on_oom=1" \ | -m 4G \ | ... Last lines from the kernel: | ... | goldfish_rtc 101000.rtc: registered as rtc0 | goldfish_rtc 101000.rtc: setting system clock to 2024-01-30T06:39:28 UTC (1706596768) Same kernel boots w/ "-machine virt,acpi=off" (AIA is *not* enabled). Related or not, I got this splat (once) a ftrace kselftest: | # selftests: ftrace: ftracetest-ktap | Unable to handle kernel paging request at virtual address 5a5a5a5a5a5a5ac2 | Oops [#1] | Modules linked in: drm fuse i2c_core drm_panel_orientation_quirks backlight dm_mod configfs ip_tables x_tables [last unloaded: trace_printk] | CPU: 2 PID: 19691 Comm: ls Tainted: G W 6.8.0-rc2-kselftest_plain #1 | Hardware name: riscv-virtio,qemu (DT) | epc : set_top_events_ownership+0x14/0x5c | ra : eventfs_get_attr+0x2e/0x50 | epc : ffffffff80533aa4 ra : ffffffff80533b1a sp : ff20000001cebc70 | gp : ffffffff8258b860 tp : ff6000008623e240 t0 : ffffffff80533a98 | t1 : ffffffff825b6b60 t2 : 0000000000000008 s0 : ff20000001cebc80 | s1 : ffffffff8233c000 a0 : ff6000009224e9b8 a1 : ff20000001cebd28 | a2 : ff20000001cebd98 a3 : 000000000000025e a4 : ffffffff80000000 | a5 : 5a5a5a5a5a5a5a5a a6 : 0000000000000000 a7 : 0000000000735049 | s2 : 000000000000025e s3 : ff20000001cebd98 s4 : ff6000009224e9b8 | s5 : ff20000001cebd28 s6 : ffffffffffffff9c s7 : ff6000008ac6a1c0 | s8 : 00007fff9f685d80 s9 : 0000000000000000 s10: 00007fffd4550ef0 | s11: 0000000000000000 t3 : 0000000000000001 t4 : 0000000000000016 | t5 : ffffffff818145be t6 : ff6000009233d77e | status: 0000000200000120 badaddr: 5a5a5a5a5a5a5ac2 cause: 000000000000000d | [<ffffffff80533aa4>] set_top_events_ownership+0x14/0x5c | Code: b297 ffad 82e7 d302 1141 e422 0800 3783 ff85 cb89 (57b8) 8b09 | ---[ end trace 0000000000000000 ]--- This might be unrelated, but the hang above is on every boot. Björn
