On Wed, 2020-02-26 at 15:46 -0800, Palmer Dabbelt wrote: > On Tue, 25 Feb 2020 17:10:32 PST (-0800), Atish Patra wrote: > > This series adds UEFI support for RISC-V. Currently, only boot time > > services have been added. Runtime services will be added in a > > separate > > series. This series depends on some core EFI patches > > present in current in efi-next and following other patches. > > > > U-Boot: Adds the boot hartid under chosen node. > > https://lists.denx.de/pipermail/u-boot/2020-February/401227.html > > > > Linux kernel: SBI v0.2 and HSM extension support. This series is a > > mandatory > > pre-requisite for UEFI support as only single core can boot EFI > > stub and > > Linux via UEFI. All other cores are brought up using SBI HSM > > extension. > > http://lists.infradead.org/pipermail/linux-riscv/2020-February/008513.html > > > > OpenSBI: master (commit: ge3f69fc1e934) > > > > Patch 1 just moves arm-stub code to a generic code so that it can > > be used > > across different architecture. > > > > Patch 3 adds fixmap bindings so that CONFIG_EFI can be compiled and > > we do not > > have create separate config to enable boot time services. > > As runtime services are not enabled at this time, full generic > > early ioremap > > support is also not added in this series. > > > > Patch 4 and 5 adds the PE/COFF header and EFI stub code support for > > RISC-V > > respectively. > > > > The patches can also be found in following git repo. > > > > https://github.com/atishp04/linux/tree/wip_uefi_riscv > > > > The patches have been verified on Qemu using bootefi command in U- > > Boot. > > Here is a boot log. > > > > Atish Patra (5): > > efi: Move arm-stub to a common file > > include: pe.h: Add RISC-V related PE definition > > RISC-V: Define fixmap bindings for generic early ioremap support > > RISC-V: Add PE/COFF header for EFI stub > > RISC-V: Add EFI stub support. > > > > arch/arm/Kconfig | 2 +- > > arch/arm64/Kconfig | 2 +- > > arch/riscv/Kconfig | 21 +++ > > arch/riscv/Makefile | 1 + > > arch/riscv/configs/defconfig | 1 + > > arch/riscv/include/asm/Kbuild | 2 +- > > arch/riscv/include/asm/fixmap.h | 21 ++- > > arch/riscv/include/asm/io.h | 1 + > > arch/riscv/include/asm/sections.h | 13 ++ > > arch/riscv/kernel/Makefile | 4 + > > arch/riscv/kernel/efi-header.S | 107 ++++++++++++++ > > arch/riscv/kernel/head.S | 15 ++ > > arch/riscv/kernel/image-vars.h | 52 +++++++ > > arch/riscv/kernel/vmlinux.lds.S | 27 +++- > > drivers/firmware/efi/Kconfig | 6 +- > > drivers/firmware/efi/libstub/Makefile | 20 ++- > > .../efi/libstub/{arm-stub.c => efi-stub.c} | 7 +- > > drivers/firmware/efi/libstub/riscv-stub.c | 135 > > ++++++++++++++++++ > > include/linux/pe.h | 3 + > > 19 files changed, 420 insertions(+), 20 deletions(-) > > create mode 100644 arch/riscv/include/asm/sections.h > > create mode 100644 arch/riscv/kernel/efi-header.S > > create mode 100644 arch/riscv/kernel/image-vars.h > > rename drivers/firmware/efi/libstub/{arm-stub.c => efi-stub.c} > > (98%) > > create mode 100644 drivers/firmware/efi/libstub/riscv-stub.c > > I'm in favor of adding EFI support, and I'd rather have it sooner > than later so > we don't paint ourselves into a corner. I'm not sure what happened > to the > RISC-V EFI spec process, though, which would be my only worry here > (also I > haven't looked at the code :)). Do we have enough of a spec through > the EFI > process that this is all kosher on their end? > The RISC-V platform is already merged in UEFI spec. The latest UEFI spec can be found here. https://uefi.org/sites/default/files/resources/UEFI_Spec_2_8_A_Feb14.pdf Section 2.3.7: RISC-V Platforms There are some modification required in the current spec. For example: The current spec assumes that UEFI will execute in M mode only and should perform handoff control to OS in M-mode as well. This is not entirely correct as we can do this in S-mode as well. We are in the process of creating an ECR so that next release will have the correct information. > Given that this definately isn't for these RCs, I'm going to leave it > in my > review queue. It might be best to get the "move stuff to generic" > work merged > on its own, as then we can carry less diff around. > > Yup. It's definitely not rc material. Given that RISC-V specific section is already merged in UEFI spec, can we aim for 5.7 merge window? > Thanks! -- Regards, Atish
