On Wed, Aug 5, 2020 at 7:17 AM Palmer Dabbelt <palmer@xxxxxxxxxxx> wrote: > > On Fri, 24 Jul 2020 00:18:18 PDT (-0700), Anup Patel wrote: > > The current RISC-V timer driver is convoluted and implements two > > distinct timers: > > 1. S-mode timer: This is for Linux RISC-V S-mode with MMU. The > > clocksource is implemented using TIME CSR and clockevent device > > is implemented using SBI Timer calls. > > 2. M-mode timer: This is for Linux RISC-V M-mode without MMU. The > > clocksource is implemented using CLINT MMIO time register and > > clockevent device is implemented using CLINT MMIO timecmp registers. > > > > This patchset removes clint related code from RISC-V timer driver and > > arch/riscv directory. Instead, the series adds a dedicated MMIO based > > CLINT driver under drivers/clocksource directory which can be used by > > Linux RISC-V M-mode (i.e NoMMU Linux RISC-V). > > > > The patchset is based up Linux-5.8-rc6 and can be found at riscv_clint_v6 > > 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 v5: > > - Fixed order of compatible strings in PATCH4 > > - Added "additionalProperties: false" in PATCH4 > > - Fixed register space size for example DT node in PATCH4 > > > > Changes since v4: > > - Rebased series on Linux-5.8-rc6 > > - Updated Kconfig option as suggested by Daniel in PATCH2 > > - Removed per-CPU registered flag in PATCH2 > > - Addressed nit comments from Atish in PATCH2 > > > > Changes since v3: > > - Updated commit description of PATCH2 > > - Use clint_get_cycles64() in clint_rdtime() of PATCH2 > > - Call clockevents_config_and_register() only once for each CPU in > > clint_timer_starting_cpu of PATCH2 > > - Select CLINT timer driver from platform Kconfig in PATCH3 > > - Fixed 'make dt_binding_check' for PATCH4 > > > > Changes since v2: > > - Rebased series on Linux-5.8-rc5 > > - Squashed PATCH3 onto PATCH2 to preserve GIT bisectability > > - Moved PATCH4 before PATCH2 to preserve GIT bisectability > > - Replaced CLINT dt-bindings text document with YAML schema > > - Use SiFive CLINT compatible string as per SiFive IP block versioning > > > > Changes since v1: > > - Rebased series on Linux-5.8-rc2 > > - Added pr_warn() for case where ipi_ops not available in PATCH1 > > - Updated ipi_inject() prototype to use "struct cpumask *" in PATCH1 > > - Updated CLINT_TIMER kconfig option to depend on RISCV_M_MODE in PATCH4 > > - Added riscv,clint0 compatible string in DT bindings document > > > > Anup Patel (4): > > RISC-V: Add mechanism to provide custom IPI operations > > clocksource/drivers: Add CLINT timer driver > > RISC-V: Remove CLINT related code from timer and arch > > dt-bindings: timer: Add CLINT bindings > > > > .../bindings/timer/sifive,clint.yaml | 60 +++++ > > arch/riscv/Kconfig | 2 +- > > arch/riscv/Kconfig.socs | 2 + > > arch/riscv/configs/nommu_virt_defconfig | 7 +- > > arch/riscv/include/asm/clint.h | 39 --- > > arch/riscv/include/asm/smp.h | 19 ++ > > arch/riscv/include/asm/timex.h | 28 +-- > > arch/riscv/kernel/Makefile | 2 +- > > arch/riscv/kernel/clint.c | 44 ---- > > arch/riscv/kernel/sbi.c | 14 ++ > > arch/riscv/kernel/setup.c | 2 - > > arch/riscv/kernel/smp.c | 44 ++-- > > arch/riscv/kernel/smpboot.c | 4 +- > > drivers/clocksource/Kconfig | 12 +- > > drivers/clocksource/Makefile | 1 + > > drivers/clocksource/timer-clint.c | 226 ++++++++++++++++++ > > drivers/clocksource/timer-riscv.c | 17 +- > > include/linux/cpuhotplug.h | 1 + > > 18 files changed, 371 insertions(+), 153 deletions(-) > > create mode 100644 Documentation/devicetree/bindings/timer/sifive,clint.yaml > > delete mode 100644 arch/riscv/include/asm/clint.h > > delete mode 100644 arch/riscv/kernel/clint.c > > create mode 100644 drivers/clocksource/timer-clint.c > > Thanks, this is way cleaner. Patchwork is still broken but IIRC we reached > consensus on these. I'm not going to include these in my first 5.9 PR, as I > want to get that out tomorrow to avoid more merge conflicts, but assuming > there's reviews from the other maintainers I'd like to take this for my second > 5.9 merge window PR. > > Assuming you've been collecting reviews and acks, do you mind posting another > version with them? If not I have some scripts to dig them out, so it's not a > big deal. Most of the Reviewed-by and Ack-by are already there, except yours and Rob Herring's Reviewed-by. I will post v7 based on Linux-5.9-rc1 Regards, Anup
