Re: [PATCH v5 0/3] RISC-V: Add ACPI support for IOMMU

From: Palmer Dabbelt
Date: Wed Jul 16 2025 - 11:27:57 EST


On Wed, 16 Jul 2025 03:40:56 PDT (-0700), Sunil V L wrote:
This series adds support for RISC-V IOMMU on ACPI based platforms.
RISC-V IO Mapping Table (RIMT) is a new static ACPI table [1] introduced
to communicate IOMMU information to the OS.

[1] - https://github.com/riscv-non-isa/riscv-acpi-rimt/releases/download/v1.0/rimt-spec.pdf

Changes since v4:
1) Rebased to 6.16-rc6
2) Addressed Anup's feedback on formatting.
3) Added RB tag from Will and Anup.

Changes since v3:
1) Rebased to 6.16-rc5
2) Addressed Drew's feedback on v3.
a) Reordered calling rimt_iommu_configure_id().
b) Removed unnecessary inline.
c) Added pr_fmt.
d) Removed redundant rimt_iommu_configure_id() stub.
3) Added Drew's RB tag in PATCH 3.

Changes since v2:
1) Rebased to 6.16-rc4
2) Removed Anup's SOB and link tags added by mistake in v2.

Changes since v1:
1) Rebased to v6.16-rc1.
2) Dropped ACPICA patch since it is already available in 6.16-rc1.
3) Added Rafael's ACK.
4) Fixed few issues found by bots.

Sunil V L (3):
ACPI: RISC-V: Add support for RIMT
ACPI: scan: Add support for RISC-V in acpi_iommu_configure_id()
iommu/riscv: Add ACPI support

MAINTAINERS | 1 +
arch/riscv/Kconfig | 1 +
drivers/acpi/Kconfig | 4 +
drivers/acpi/riscv/Kconfig | 7 +
drivers/acpi/riscv/Makefile | 1 +
drivers/acpi/riscv/init.c | 2 +
drivers/acpi/riscv/init.h | 1 +
drivers/acpi/riscv/rimt.c | 520 +++++++++++++++++++++++++++
drivers/acpi/scan.c | 4 +
drivers/iommu/riscv/iommu-platform.c | 17 +-
drivers/iommu/riscv/iommu.c | 10 +
include/linux/acpi_rimt.h | 28 ++

Thanks. Anup came to the patchwork meeting this morning and asked me to pick it up. It only barely touches arch/riscv stuff so I'd figured it was going somewhere else, but happy to do so. I've picked it up into my staging tree as

* e5efe466d9bd - (HEAD -> for-next, palmer/for-next) Merge patch series "RISC-V: Add ACPI support for IOMMU" (2 minutes ago) <Palmer Dabbelt>
|\
| * 368ed89f7ac9 - iommu/riscv: Add ACPI support (2 minutes ago) <Sunil V L>
| * 0d7c16d0df92 - ACPI: scan: Add support for RISC-V in acpi_iommu_configure_id() (2 minutes ago) <Sunil V L>
| * ea35561bc965 - ACPI: RISC-V: Add support for RIMT (2 minutes ago) <Sunil V L>

it should show up on for-next assuming it builds and such (it's behind some fixes, so might take a bit). Happy to do a tag if someone wants, just let me know...

12 files changed, 595 insertions(+), 1 deletion(-)
create mode 100644 drivers/acpi/riscv/Kconfig
create mode 100644 drivers/acpi/riscv/rimt.c
create mode 100644 include/linux/acpi_rimt.h