| Message ID | 20200611061350.434293-1-anup.patel@wdc.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | New RISC-V Local Interrupt Controller Driver | expand |
On Wed, 10 Jun 2020 23:13:44 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. > > It is a major re-write over perviously submitted version. > (Refer, https://www.spinics.net/lists/devicetree/msg241230.html) > > 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 2537 891 870 Rescheduling interrupts > IPI1: 9 269 91 168 Function call interrupts > IPI2: 0 0 0 0 CPU stop interrupts > > The patchset is based upon Linux-5.7 and can be found at riscv_intc_v7 > 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 v7: > - Rebased on Linux-5.7 release > - Minor typo-fix in pr_warn() of PATCH3 My PR was tagged before v8 was sent out, and while I haven't sent it yet (I like to give the autobuilders at least a day to chew on it) I don't want to re-spin everything this late in the merge window for a spelling issue in a warning message. I'll split the fix out as its own patch. Thanks for fixing it, though! > Changes since v6: > - Rebased patches on Linux-5.7 and tested with runtime CPU hotplug > - Minor changes in PATCH3 as suggested by Marc Z > - Don't programm PLIC threshold for CPU_OFF in PATCH3 > - Simplified finding IRQ domain in riscv_timer_init_dt() of PATCH4 > > Changes since v5: > - Rebased to Linux-5.7-rc7 with PLIC improvement patches > - Removed riscv_of_parent_hartid() from PATCH3 > - Addressed other minor comments from Palmer and Marc Z > > 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 | 43 ++++++++- > drivers/irqchip/Kconfig | 13 +++ > drivers/irqchip/Makefile | 1 + > drivers/irqchip/irq-riscv-intc.c | 138 +++++++++++++++++++++++++++++ > drivers/irqchip/irq-sifive-plic.c | 44 ++++----- > include/linux/cpuhotplug.h | 1 + > 15 files changed, 252 insertions(+), 65 deletions(-) > create mode 100644 drivers/irqchip/irq-riscv-intc.c
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. It is a major re-write over perviously submitted version. (Refer, https://www.spinics.net/lists/devicetree/msg241230.html) 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 2537 891 870 Rescheduling interrupts IPI1: 9 269 91 168 Function call interrupts IPI2: 0 0 0 0 CPU stop interrupts The patchset is based upon Linux-5.7 and can be found at riscv_intc_v7 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 v7: - Rebased on Linux-5.7 release - Minor typo-fix in pr_warn() of PATCH3 Changes since v6: - Rebased patches on Linux-5.7 and tested with runtime CPU hotplug - Minor changes in PATCH3 as suggested by Marc Z - Don't programm PLIC threshold for CPU_OFF in PATCH3 - Simplified finding IRQ domain in riscv_timer_init_dt() of PATCH4 Changes since v5: - Rebased to Linux-5.7-rc7 with PLIC improvement patches - Removed riscv_of_parent_hartid() from PATCH3 - Addressed other minor comments from Palmer and Marc Z 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 | 43 ++++++++- drivers/irqchip/Kconfig | 13 +++ drivers/irqchip/Makefile | 1 + drivers/irqchip/irq-riscv-intc.c | 138 +++++++++++++++++++++++++++++ drivers/irqchip/irq-sifive-plic.c | 44 ++++----- include/linux/cpuhotplug.h | 1 + 15 files changed, 252 insertions(+), 65 deletions(-) create mode 100644 drivers/irqchip/irq-riscv-intc.c