[PATCH v7 0/7] RISC-V IPI Improvements
Anup Patel
apatel at ventanamicro.com
Wed Jul 20 08:23:41 PDT 2022
This series aims to improve IPI support in Linux RISC-V in following ways:
1) Treat IPIs as normal per-CPU interrupts instead of having custom RISC-V
specific hooks. This also makes Linux RISC-V IPI support aligned with
other architectures.
2) Remote TLB flushes and icache flushes should prefer local IPIs instead
of SBI calls whenever we have specialized hardware (such as RISC-V AIA
IMSIC and RISC-V SWI) which allows S-mode software to directly inject
IPIs without any assistance from M-mode runtime firmware.
These patches were originally part of the "Linux RISC-V ACLINT Support"
series but this now a separate series so that it can be merged independently
of the "Linux RISC-V ACLINT Support" series.
(Refer, https://lore.kernel.org/lkml/20211007123632.697666-1-anup.patel@wdc.com/)
These patches are also a preparatory patches for the up-coming:
1) Linux RISC-V AIA support
2) KVM RISC-V TLB flush improvements
3) Linux RISC-V SWI support
These patches can also be found in riscv_ipi_imp_v7 branch at:
https://github.com/avpatel/linux.git
Changes since v6:
- Rebased on Linux-5.19-rc7
- Added documentation for struct ipi_mux_ops in PATCH3
- Dropped dummy irq_mask()/unmask() in PATCH3
- Added const for "ipi_mux_chip" in PATCH3
- Removed "type" initialization from ipi_mux_domain_alloc() in PATCH3
- Dropped translate() from "ipi_mux_domain_ops" in PATCH3
- Improved barrier documentation in ipi_mux_process() of PATCH3
- Added percpu check in ipi_mux_create() for parent_virq of PATCH3
- Added nr_ipi parameter in ipi_mux_create() of PATCH3
Changes since v5:
- Rebased on Linux-5.18-rc3
- Used kernel doc style in PATCH3
- Removed redundant loop in ipi_mux_process() of PATCH3
- Removed "RISC-V" prefix form ipi_mux_chip.name of PATCH3
- Removed use of "this patch" in PATCH3 commit description
- Addressed few other nit comments in PATCH3
Changes since v4:
- Rebased on Linux-5.17
- Includes new PATCH3 which adds mechanism to multiplex a single HW IPI
Changes since v3:
- Rebased on Linux-5.17-rc6
- Updated PATCH2 to not export riscv_set_intc_hwnode_fn()
- Simplified riscv_intc_hwnode() in PATCH2
Changes since v2:
- Rebased on Linux-5.17-rc4
- Updated PATCH2 to not create synthetic INTC fwnode and instead provide
a function which allows drivers to directly discover INTC fwnode
Changes since v1:
- Use synthetic fwnode for INTC instead of irq_set_default_host() in PATCH2
Anup Patel (7):
RISC-V: Clear SIP bit only when using SBI IPI operations
irqchip/riscv-intc: Allow drivers to directly discover INTC hwnode
genirq: Add mechanism to multiplex a single HW IPI
RISC-V: Treat IPIs as normal Linux IRQs
RISC-V: Allow marking IPIs as suitable for remote FENCEs
RISC-V: Use IPIs for remote TLB flush when possible
RISC-V: Use IPIs for remote icache flush when possible
arch/riscv/Kconfig | 2 +
arch/riscv/include/asm/irq.h | 4 +
arch/riscv/include/asm/sbi.h | 2 +
arch/riscv/include/asm/smp.h | 51 +++++---
arch/riscv/kernel/Makefile | 1 +
arch/riscv/kernel/cpu-hotplug.c | 3 +-
arch/riscv/kernel/irq.c | 21 +++-
arch/riscv/kernel/sbi-ipi.c | 60 +++++++++
arch/riscv/kernel/sbi.c | 11 --
arch/riscv/kernel/smp.c | 167 +++++++++++++------------
arch/riscv/kernel/smpboot.c | 5 +-
arch/riscv/mm/cacheflush.c | 5 +-
arch/riscv/mm/tlbflush.c | 93 +++++++++++---
drivers/clocksource/timer-clint.c | 41 ++++--
drivers/irqchip/irq-riscv-intc.c | 60 ++++-----
include/linux/irq.h | 16 +++
kernel/irq/Kconfig | 4 +
kernel/irq/Makefile | 1 +
kernel/irq/ipi-mux.c | 199 ++++++++++++++++++++++++++++++
19 files changed, 579 insertions(+), 167 deletions(-)
create mode 100644 arch/riscv/kernel/sbi-ipi.c
create mode 100644 kernel/irq/ipi-mux.c
--
2.34.1
More information about the linux-riscv
mailing list