Re: [RFC PATCH v4 00/20] RISC-V: ACPI: Add external interrupt controller support

[Sunil V L <sunilvl@ventanamicro.com>]

On Thu, Apr 18, 2024 at 03:49:22PM +0200, Björn Töpel wrote:
> Sunil V L <sunilvl@ventanamicro.com> writes:
> 
> > 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) When PNP devices like Generic 16550A UART, have the dependency on the
> > interrupt controller, they will not be added to PNP data structures. So,
> > added second phase of pnpacpi_init to handle this.
> >
> > 5) ACPI support added in RISC-V interrupt controller drivers.
> >
> > This series is still kept as RFC to seek feedback on above design
> > changes. Looking forward for the feedback!
> >
> > 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_v1 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
> 
> Hi Sunil,
> 
> I started playing with your work, and FYI: Using U-boot instead of EDK2
> works out of the box (with acpi.config added to U-boot).
> 
> I changed my rootfs/boot tooling like [1], and it boots.
> 
> (For those who prefer working with U-boot UEFI instead of EDK2.)
> 
> 
Hi Björn,

This is cool!. I was not aware that u-boot also supports ACPI on
RISC-V. Many thanks!

Thanks,
Sunil