[PATCH v5 00/17] RISC-V: ACPI: Add external interrupt controller support

From: Sunil V L
Date: Wed May 01 2024 - 08:18:15 EST


This series adds support for the below ECR approved by ASWG.
1) MADT - https://drive.google.com/file/d/1oMGPyOD58JaPgMl1pKasT-VKsIKia7zR/view?usp=sharing

The series primarily enables irqchip drivers for RISC-V ACPI based
platforms.

The series can be broadly categorized like below.

1) PCI ACPI related functions are migrated from arm64 to common file so
that we don't need to duplicate them for RISC-V.

2) Added support for re-ordering the probe of interrupt controllers when
IRQCHIP_ACPI_DECLARE is used.

3) To ensure probe order between interrupt controllers and devices,
implicit dependency is created similar to when _DEP is present.

4) Added 8250 serial driver for a generic 16550 UART which is enumerated
as ACPI platform device.

5) ACPI support added in RISC-V interrupt controller drivers.

Changes since RFC v4:
1) Removed RFC tag as the RFCv4 design looked reasonable.
2) Dropped PCI patch needed to avoid warning when there is no MSI
controller. This will be sent later separately after the
current series.
3) Dropped PNP handling of _DEP since there is new ACPI ID for
generic 16550 UART. Added the serial driver patch instead.
4) Rebased to latest linux-next.
5) Reordered/squashed patches in the series

Changes since RFC v3:
1) Moved to _DEP method instead of fw_devlink.
2) PLIC/APLIC driver probe using namespace devices.
3) Handling PNP devices as part of clearing dependency.
4) Rebased to latest linux-next to get AIA DT drivers.

Changes since RFC v2:
1) Introduced fw_devlink for ACPI nodes for IRQ dependency.
2) Dropped patches in drivers which are not required due to
fw_devlink support.
3) Dropped pci_set_msi() patch and added a patch in
pci_create_root_bus().
4) Updated pnp_irq() patch so that none of the actual PNP
drivers need to change.

Changes since RFC v1:
1) Abandoned swnode approach as per Marc's feedback.
2) To cope up with AIA series changes which changed irqchip driver
probe from core_initcall() to platform_driver, added patches
to support deferred probing.
3) Rebased on top of Anup's AIA v11 and added tags.

To test the series,

1) qemu should be built using the riscv_acpi_namespace_v2 branch at
https://github.com/vlsunil/qemu.git

2) EDK2 should be built using the instructions at:
https://github.com/tianocore/edk2/blob/master/OvmfPkg/RiscVVirt/README.md

NOTE: One should be able to use u-boot as well as per instructions from Björn.
https://lore.kernel.org/lkml/87a5lqsrvh.fsf@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/

3) Build Linux using this series.

Run Qemu:
qemu-system-riscv64 \
-M virt,pflash0=pflash0,pflash1=pflash1,aia=aplic-imsic \
-m 2G -smp 8 \
-serial mon:stdio \
-device virtio-gpu-pci -full-screen \
-device qemu-xhci \
-device usb-kbd \
-blockdev node-name=pflash0,driver=file,read-only=on,filename=RISCV_VIRT_CODE.fd \
-blockdev node-name=pflash1,driver=file,filename=RISCV_VIRT_VARS.fd \
-netdev user,id=net0 -device virtio-net-pci,netdev=net0 \
-kernel arch/riscv/boot/Image \
-initrd rootfs.cpio \
-append "root=/dev/ram ro console=ttyS0 rootwait earlycon=uart8250,mmio,0x10000000"

To boot with APLIC only, use aia=aplic.
To boot with PLIC, remove aia= option.

This series is also available in acpi_b2_v5 branch at
https://github.com/vlsunil/linux.git

Based-on: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tag/?h=next-20240501

Sunil V L (17):
arm64: PCI: Migrate ACPI related functions to pci-acpi.c
ACPI: scan: Add a weak function to reorder the IRQCHIP probe
ACPI: bus: Add acpi_riscv_init function
ACPI: scan: Refactor dependency creation
ACPI: scan: Add RISC-V interrupt controllers to honor list
ACPI: scan: Define weak function to populate dependencies
ACPI: bus: Add RINTC IRQ model for RISC-V
ACPI: pci_link: Clear the dependencies after probe
ACPI: RISC-V: Implement PCI related functionality
ACPI: RISC-V: Implement function to reorder irqchip probe entries
ACPI: RISC-V: Initialize GSI mapping structures
ACPI: RISC-V: Implement function to add implicit dependencies
irqchip/riscv-intc: Add ACPI support for AIA
irqchip/riscv-imsic: Add ACPI support
irqchip/riscv-aplic: Add ACPI support
irqchip/sifive-plic: Add ACPI support
serial: 8250: Add 8250_acpi driver

arch/arm64/kernel/pci.c | 191 ------------
arch/riscv/Kconfig | 3 +
arch/riscv/configs/defconfig | 1 +
arch/riscv/include/asm/irq.h | 57 ++++
arch/riscv/kernel/acpi.c | 31 +-
drivers/acpi/Kconfig | 3 +
drivers/acpi/bus.c | 4 +
drivers/acpi/pci_link.c | 3 +
drivers/acpi/riscv/Makefile | 2 +-
drivers/acpi/riscv/init.c | 14 +
drivers/acpi/riscv/init.h | 4 +
drivers/acpi/riscv/irq.c | 329 +++++++++++++++++++++
drivers/acpi/scan.c | 65 ++--
drivers/irqchip/irq-riscv-aplic-direct.c | 20 +-
drivers/irqchip/irq-riscv-aplic-main.c | 70 +++--
drivers/irqchip/irq-riscv-aplic-main.h | 1 +
drivers/irqchip/irq-riscv-aplic-msi.c | 9 +-
drivers/irqchip/irq-riscv-imsic-early.c | 52 +++-
drivers/irqchip/irq-riscv-imsic-platform.c | 32 +-
drivers/irqchip/irq-riscv-imsic-state.c | 115 ++++---
drivers/irqchip/irq-riscv-imsic-state.h | 2 +-
drivers/irqchip/irq-riscv-intc.c | 102 ++++++-
drivers/irqchip/irq-sifive-plic.c | 89 ++++--
drivers/pci/pci-acpi.c | 182 ++++++++++++
drivers/tty/serial/8250/8250_acpi.c | 96 ++++++
drivers/tty/serial/8250/Kconfig | 8 +
drivers/tty/serial/8250/Makefile | 1 +
include/acpi/acpi_bus.h | 2 +
include/linux/acpi.h | 9 +
include/linux/irqchip/riscv-imsic.h | 10 +
30 files changed, 1155 insertions(+), 352 deletions(-)
create mode 100644 drivers/acpi/riscv/init.c
create mode 100644 drivers/acpi/riscv/init.h
create mode 100644 drivers/acpi/riscv/irq.c
create mode 100644 drivers/tty/serial/8250/8250_acpi.c

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2.40.1