Re: [PATCH v5 0/6] New RISC-V Local Interrupt Controller Driver
On 2020-05-27 19:47, Palmer Dabbelt wrote: [...] I think it's best if this all goes in through a single tree, as it seems more work than it's worth to split it up. I'm happy to take it through my tree if that's OK with the irqchip folks? This still needs some fixing on patch 3 (the exported symbol is pretty awful), but this should definitely go via the RISC-V tree. Thanks, M. -- Jazz is not dead. It just smells funny...
RE: [PATCH v5 0/6] New RISC-V Local Interrupt Controller Driver
> -Original Message- > From: linux-kernel-ow...@vger.kernel.org ow...@vger.kernel.org> On Behalf Of Palmer Dabbelt > Sent: 29 May 2020 09:43 > To: a...@brainfault.org > Cc: Marc Zyngier ; Anup Patel ; Paul > Walmsley ; a...@eecs.berkeley.edu; > daniel.lezc...@linaro.org; t...@linutronix.de; ja...@lakedaemon.net; Atish > Patra ; Alistair Francis ; > linux-ri...@lists.infradead.org; linux-kernel@vger.kernel.org > Subject: Re: [PATCH v5 0/6] New RISC-V Local Interrupt Controller Driver > > On Thu, 28 May 2020 20:57:26 PDT (-0700), a...@brainfault.org wrote: > > On Thu, May 28, 2020 at 12:17 AM Palmer Dabbelt > wrote: > >> > >> On Thu, 21 May 2020 06:32:55 PDT (-0700), Anup Patel wrote: > >> > This patchset provides a new RISC-V Local Interrupt Controller > >> > Driver for managing per-CPU local interrupts. The overall approach > >> > is inspired from the way per-CPU local interrupts are handled by > >> > Linux ARM64 and ARM GICv3 driver. > >> > > >> > Few advantages of this new driver over previous one are: > >> > 1. All local interrupts are registered as per-CPU interrupts 2. The > >> > RISC-V timer driver can register timer interrupt handler > >> >using kernel irq subsystem without relying on arch/riscv to > >> >explicitly call it's interrupt handler 3. The KVM RISC-V can use > >> > this driver to implement interrupt > >> >handler for per-HART guest external interrupt defined by > >> >the RISC-V H-Extension > >> > 4. In future, we can develop drivers for devices with per-HART > >> >interrupts without changing arch code or this driver (example, > >> >CLINT timer driver for RISC-V M-mode kernel) > >> > > >> > With this patchset, output of "cat /proc/interrupts" looks as follows: > >> >CPU0 CPU1 CPU2 CPU3 > >> > 2:379 0 0 0 SiFive PLIC 10 ttyS0 > >> > 3:591 0 0 0 SiFive PLIC 8 > >> > virtio0 > >> > 5: 5079 10821 8435 12984 RISC-V INTC 5 > >> > riscv-timer > >> > IPI0: 2045 2537891870 Rescheduling interrupts > >> > IPI1: 9269 91168 Function call > >> > interrupts > >> > IPI2: 0 0 0 0 CPU stop interrupts > >> > > >> > The patchset is based up Linux-5.7-rc6 and can be found at > >> > riscv_intc_v5 branch of: https://github.com/avpatel/linux.git > >> > > >> > This series is tested on: > >> > 1. QEMU RV64 virt machine using Linux RISC-V S-mode 2. QEMU RV32 > >> > virt machine using Linux RISC-V S-mode 3. QEMU RV64 virt machine > >> > using Linux RISC-V M-mode (i.e. NoMMU) > >> > > >> > Changes since v4: > >> > - Rebased to Linux-5.7-rc6 and multi-PLIC improvement patches > >> > - Added separate patch to force select RISCV_INTC for CONFIG_RISCV > >> > - Fixed the driver for Linux RISC-V NoMMU > >> > > >> > Changes since v3: > >> > - Rebased to Linux-5.6-rc5 and Atish's PLIC patches > >> > - Added separate patch to rename and move plic_find_hart_id() > >> >to arch directory > >> > - Use riscv_of_parent_hartid() in riscv_intc_init() instead of > >> >atomic counter > >> > > >> > Changes since v2: > >> > - Dropped PATCH2 since it was merged long-time back > >> > - Rebased series from Linux-4.19-rc2 to Linux-5.6-rc2 > >> > > >> > Changes since v1: > >> > - Removed changes related to puggable IPI triggering > >> > - Separate patch for self-contained IPI handling routine > >> > - Removed patch for GENERIC_IRQ kconfig options > >> > - Added patch to remove do_IRQ() function > >> > - Rebased upon Atish's SMP patches > >> > > >> > Anup Patel (6): > >> > RISC-V: self-contained IPI handling routine > >> > RISC-V: Rename and move plic_find_hart_id() to arch directory > >> > irqchip: RISC-V per-HART local interrupt controller driver > >> > clocksource/drivers/timer-riscv: Use per-CPU timer interrupt > >> > RISC-V: Remove do_IRQ() function > >> > RISC-V: Force select RISCV_INTC for CONFIG_RISCV > >> > > >> > arch/riscv/Kc
Re: [PATCH v5 0/6] New RISC-V Local Interrupt Controller Driver
On Thu, 28 May 2020 20:57:26 PDT (-0700), a...@brainfault.org wrote: On Thu, May 28, 2020 at 12:17 AM Palmer Dabbelt wrote: On Thu, 21 May 2020 06:32:55 PDT (-0700), Anup Patel wrote: > This patchset provides a new RISC-V Local Interrupt Controller Driver > for managing per-CPU local interrupts. The overall approach is inspired > from the way per-CPU local interrupts are handled by Linux ARM64 and > ARM GICv3 driver. > > Few advantages of this new driver over previous one are: > 1. All local interrupts are registered as per-CPU interrupts > 2. The RISC-V timer driver can register timer interrupt handler >using kernel irq subsystem without relying on arch/riscv to >explicitly call it's interrupt handler > 3. The KVM RISC-V can use this driver to implement interrupt >handler for per-HART guest external interrupt defined by >the RISC-V H-Extension > 4. In future, we can develop drivers for devices with per-HART >interrupts without changing arch code or this driver (example, >CLINT timer driver for RISC-V M-mode kernel) > > With this patchset, output of "cat /proc/interrupts" looks as follows: >CPU0 CPU1 CPU2 CPU3 > 2:379 0 0 0 SiFive PLIC 10 ttyS0 > 3:591 0 0 0 SiFive PLIC 8 virtio0 > 5: 5079 10821 8435 12984 RISC-V INTC 5 riscv-timer > IPI0: 2045 2537891870 Rescheduling interrupts > IPI1: 9269 91168 Function call interrupts > IPI2: 0 0 0 0 CPU stop interrupts > > The patchset is based up Linux-5.7-rc6 and can be found at riscv_intc_v5 > branch of: https://github.com/avpatel/linux.git > > This series is tested on: > 1. QEMU RV64 virt machine using Linux RISC-V S-mode > 2. QEMU RV32 virt machine using Linux RISC-V S-mode > 3. QEMU RV64 virt machine using Linux RISC-V M-mode (i.e. NoMMU) > > Changes since v4: > - Rebased to Linux-5.7-rc6 and multi-PLIC improvement patches > - Added separate patch to force select RISCV_INTC for CONFIG_RISCV > - Fixed the driver for Linux RISC-V NoMMU > > Changes since v3: > - Rebased to Linux-5.6-rc5 and Atish's PLIC patches > - Added separate patch to rename and move plic_find_hart_id() >to arch directory > - Use riscv_of_parent_hartid() in riscv_intc_init() instead of >atomic counter > > Changes since v2: > - Dropped PATCH2 since it was merged long-time back > - Rebased series from Linux-4.19-rc2 to Linux-5.6-rc2 > > Changes since v1: > - Removed changes related to puggable IPI triggering > - Separate patch for self-contained IPI handling routine > - Removed patch for GENERIC_IRQ kconfig options > - Added patch to remove do_IRQ() function > - Rebased upon Atish's SMP patches > > Anup Patel (6): > RISC-V: self-contained IPI handling routine > RISC-V: Rename and move plic_find_hart_id() to arch directory > irqchip: RISC-V per-HART local interrupt controller driver > clocksource/drivers/timer-riscv: Use per-CPU timer interrupt > RISC-V: Remove do_IRQ() function > RISC-V: Force select RISCV_INTC for CONFIG_RISCV > > arch/riscv/Kconfig | 2 + > arch/riscv/include/asm/irq.h | 5 - > arch/riscv/include/asm/processor.h | 1 + > arch/riscv/include/asm/smp.h | 3 + > arch/riscv/kernel/cpu.c| 16 +++ > arch/riscv/kernel/entry.S | 4 +- > arch/riscv/kernel/irq.c| 33 +- > arch/riscv/kernel/smp.c| 11 +- > arch/riscv/kernel/traps.c | 2 - > drivers/clocksource/timer-riscv.c | 30 - > drivers/irqchip/Kconfig| 13 +++ > drivers/irqchip/Makefile | 1 + > drivers/irqchip/irq-riscv-intc.c | 150 + > drivers/irqchip/irq-sifive-plic.c | 52 + > include/linux/cpuhotplug.h | 1 + > include/linux/irqchip/irq-riscv-intc.h | 20 > 16 files changed, 280 insertions(+), 64 deletions(-) > create mode 100644 drivers/irqchip/irq-riscv-intc.c > create mode 100644 include/linux/irqchip/irq-riscv-intc.h So I read through this a bit, and while I haven't gone through every line of code I'm somewhat inclined toward taking it. During the original RISC-V port submission we went back and forth between having this first-level interrupt controller in arch/riscv/ vs drivers/irqchip/. The original deciding factor was that the ISA mandated the interrupt controller, but as that's proving to be less and less the case every day (with the CLIC and M-mode Linux) it certainly seem sane to move all our interrupt controller drivers out of arch/riscv/. This is certainly a step in the right direction, and it handles some of the more glaring issues (iscv_timer_interrupt and lacking IRQs for the CLINT). I think we should just go ahead and merge it, even though there might be some more refac
Re: [PATCH v5 0/6] New RISC-V Local Interrupt Controller Driver
On Thu, May 28, 2020 at 12:17 AM Palmer Dabbelt wrote: > > On Thu, 21 May 2020 06:32:55 PDT (-0700), Anup Patel wrote: > > This patchset provides a new RISC-V Local Interrupt Controller Driver > > for managing per-CPU local interrupts. The overall approach is inspired > > from the way per-CPU local interrupts are handled by Linux ARM64 and > > ARM GICv3 driver. > > > > Few advantages of this new driver over previous one are: > > 1. All local interrupts are registered as per-CPU interrupts > > 2. The RISC-V timer driver can register timer interrupt handler > >using kernel irq subsystem without relying on arch/riscv to > >explicitly call it's interrupt handler > > 3. The KVM RISC-V can use this driver to implement interrupt > >handler for per-HART guest external interrupt defined by > >the RISC-V H-Extension > > 4. In future, we can develop drivers for devices with per-HART > >interrupts without changing arch code or this driver (example, > >CLINT timer driver for RISC-V M-mode kernel) > > > > With this patchset, output of "cat /proc/interrupts" looks as follows: > >CPU0 CPU1 CPU2 CPU3 > > 2:379 0 0 0 SiFive PLIC 10 ttyS0 > > 3:591 0 0 0 SiFive PLIC 8 virtio0 > > 5: 5079 10821 8435 12984 RISC-V INTC 5 > > riscv-timer > > IPI0: 2045 2537891870 Rescheduling interrupts > > IPI1: 9269 91168 Function call interrupts > > IPI2: 0 0 0 0 CPU stop interrupts > > > > The patchset is based up Linux-5.7-rc6 and can be found at riscv_intc_v5 > > branch of: https://github.com/avpatel/linux.git > > > > This series is tested on: > > 1. QEMU RV64 virt machine using Linux RISC-V S-mode > > 2. QEMU RV32 virt machine using Linux RISC-V S-mode > > 3. QEMU RV64 virt machine using Linux RISC-V M-mode (i.e. NoMMU) > > > > Changes since v4: > > - Rebased to Linux-5.7-rc6 and multi-PLIC improvement patches > > - Added separate patch to force select RISCV_INTC for CONFIG_RISCV > > - Fixed the driver for Linux RISC-V NoMMU > > > > Changes since v3: > > - Rebased to Linux-5.6-rc5 and Atish's PLIC patches > > - Added separate patch to rename and move plic_find_hart_id() > >to arch directory > > - Use riscv_of_parent_hartid() in riscv_intc_init() instead of > >atomic counter > > > > Changes since v2: > > - Dropped PATCH2 since it was merged long-time back > > - Rebased series from Linux-4.19-rc2 to Linux-5.6-rc2 > > > > Changes since v1: > > - Removed changes related to puggable IPI triggering > > - Separate patch for self-contained IPI handling routine > > - Removed patch for GENERIC_IRQ kconfig options > > - Added patch to remove do_IRQ() function > > - Rebased upon Atish's SMP patches > > > > Anup Patel (6): > > RISC-V: self-contained IPI handling routine > > RISC-V: Rename and move plic_find_hart_id() to arch directory > > irqchip: RISC-V per-HART local interrupt controller driver > > clocksource/drivers/timer-riscv: Use per-CPU timer interrupt > > RISC-V: Remove do_IRQ() function > > RISC-V: Force select RISCV_INTC for CONFIG_RISCV > > > > arch/riscv/Kconfig | 2 + > > arch/riscv/include/asm/irq.h | 5 - > > arch/riscv/include/asm/processor.h | 1 + > > arch/riscv/include/asm/smp.h | 3 + > > arch/riscv/kernel/cpu.c| 16 +++ > > arch/riscv/kernel/entry.S | 4 +- > > arch/riscv/kernel/irq.c| 33 +- > > arch/riscv/kernel/smp.c| 11 +- > > arch/riscv/kernel/traps.c | 2 - > > drivers/clocksource/timer-riscv.c | 30 - > > drivers/irqchip/Kconfig| 13 +++ > > drivers/irqchip/Makefile | 1 + > > drivers/irqchip/irq-riscv-intc.c | 150 + > > drivers/irqchip/irq-sifive-plic.c | 52 + > > include/linux/cpuhotplug.h | 1 + > > include/linux/irqchip/irq-riscv-intc.h | 20 > > 16 files changed, 280 insertions(+), 64 deletions(-) > > create mode 100644 drivers/irqchip/irq-riscv-intc.c > > create mode 100644 include/linux/irqchip/irq-riscv-intc.h > > So I read through this a bit, and while I haven't gone through every line of > code I'm somewhat inclined toward taking it. > > During the original RISC-V port submission we went back and forth between > having this first-level interrupt controller in arch/riscv/ vs > drivers/irqchip/. The original deciding factor was that the ISA mandated the > interrupt controller, but as that's proving to be less and less the case every > day (with the CLIC and M-mode Linux) it certainly seem sane to move all our > interrupt controller drivers out of arch/riscv/. > > This is certainly a step in the right direction, and it handles some of the > more glaring issues (iscv_timer_inter
Re: [PATCH v5 0/6] New RISC-V Local Interrupt Controller Driver
On Thu, 21 May 2020 06:32:55 PDT (-0700), Anup Patel wrote: This patchset provides a new RISC-V Local Interrupt Controller Driver for managing per-CPU local interrupts. The overall approach is inspired from the way per-CPU local interrupts are handled by Linux ARM64 and ARM GICv3 driver. Few advantages of this new driver over previous one are: 1. All local interrupts are registered as per-CPU interrupts 2. The RISC-V timer driver can register timer interrupt handler using kernel irq subsystem without relying on arch/riscv to explicitly call it's interrupt handler 3. The KVM RISC-V can use this driver to implement interrupt handler for per-HART guest external interrupt defined by the RISC-V H-Extension 4. In future, we can develop drivers for devices with per-HART interrupts without changing arch code or this driver (example, CLINT timer driver for RISC-V M-mode kernel) With this patchset, output of "cat /proc/interrupts" looks as follows: CPU0 CPU1 CPU2 CPU3 2:379 0 0 0 SiFive PLIC 10 ttyS0 3:591 0 0 0 SiFive PLIC 8 virtio0 5: 5079 10821 8435 12984 RISC-V INTC 5 riscv-timer IPI0: 2045 2537891870 Rescheduling interrupts IPI1: 9269 91168 Function call interrupts IPI2: 0 0 0 0 CPU stop interrupts The patchset is based up Linux-5.7-rc6 and can be found at riscv_intc_v5 branch of: https://github.com/avpatel/linux.git This series is tested on: 1. QEMU RV64 virt machine using Linux RISC-V S-mode 2. QEMU RV32 virt machine using Linux RISC-V S-mode 3. QEMU RV64 virt machine using Linux RISC-V M-mode (i.e. NoMMU) Changes since v4: - Rebased to Linux-5.7-rc6 and multi-PLIC improvement patches - Added separate patch to force select RISCV_INTC for CONFIG_RISCV - Fixed the driver for Linux RISC-V NoMMU Changes since v3: - Rebased to Linux-5.6-rc5 and Atish's PLIC patches - Added separate patch to rename and move plic_find_hart_id() to arch directory - Use riscv_of_parent_hartid() in riscv_intc_init() instead of atomic counter Changes since v2: - Dropped PATCH2 since it was merged long-time back - Rebased series from Linux-4.19-rc2 to Linux-5.6-rc2 Changes since v1: - Removed changes related to puggable IPI triggering - Separate patch for self-contained IPI handling routine - Removed patch for GENERIC_IRQ kconfig options - Added patch to remove do_IRQ() function - Rebased upon Atish's SMP patches Anup Patel (6): RISC-V: self-contained IPI handling routine RISC-V: Rename and move plic_find_hart_id() to arch directory irqchip: RISC-V per-HART local interrupt controller driver clocksource/drivers/timer-riscv: Use per-CPU timer interrupt RISC-V: Remove do_IRQ() function RISC-V: Force select RISCV_INTC for CONFIG_RISCV arch/riscv/Kconfig | 2 + arch/riscv/include/asm/irq.h | 5 - arch/riscv/include/asm/processor.h | 1 + arch/riscv/include/asm/smp.h | 3 + arch/riscv/kernel/cpu.c| 16 +++ arch/riscv/kernel/entry.S | 4 +- arch/riscv/kernel/irq.c| 33 +- arch/riscv/kernel/smp.c| 11 +- arch/riscv/kernel/traps.c | 2 - drivers/clocksource/timer-riscv.c | 30 - drivers/irqchip/Kconfig| 13 +++ drivers/irqchip/Makefile | 1 + drivers/irqchip/irq-riscv-intc.c | 150 + drivers/irqchip/irq-sifive-plic.c | 52 + include/linux/cpuhotplug.h | 1 + include/linux/irqchip/irq-riscv-intc.h | 20 16 files changed, 280 insertions(+), 64 deletions(-) create mode 100644 drivers/irqchip/irq-riscv-intc.c create mode 100644 include/linux/irqchip/irq-riscv-intc.h So I read through this a bit, and while I haven't gone through every line of code I'm somewhat inclined toward taking it. During the original RISC-V port submission we went back and forth between having this first-level interrupt controller in arch/riscv/ vs drivers/irqchip/. The original deciding factor was that the ISA mandated the interrupt controller, but as that's proving to be less and less the case every day (with the CLIC and M-mode Linux) it certainly seem sane to move all our interrupt controller drivers out of arch/riscv/. This is certainly a step in the right direction, and it handles some of the more glaring issues (iscv_timer_interrupt and lacking IRQs for the CLINT). I think we should just go ahead and merge it, even though there might be some more refactoring to do when we eventually end up with another interrupt controller. I think it's best if this all goes in through a single tree, as it seems more work than it's worth to split it up. I'm happy to take it through my tree if that's OK with the irqchip folks?
