On 11.05.21 05:41, Rahul Pathak wrote:
> Initial changes for the Base Boot & Runtime requirements.
> The sections which are currently in-progress are marked as TBD.
> These changes can serve as the starting point and more details/changes
> can be done tailored for RISC-V.
>
> Updated the section "Storage and Partition" along with details on
> SBI Extensions in Runtime Section.
>
> There is an patch to add RISC-V details in the EBBR spec sent by Atish.
> That patch is not yet merged in the EBBR. The section on the
> "Startup Protocol" in this spec will refer to the requirements there
> and currently that link is marked as TBD.
>
> Corrected SBI Spec version
>
> Signed-off-by: Rahul Pathak <rpathak@...>
> ---
>  riscv-platform-spec.adoc | 134 +++++++++++++++++++++++++++++++++++++--
>  1 file changed, 127 insertions(+), 7 deletions(-)
>
> diff --git a/riscv-platform-spec.adoc b/riscv-platform-spec.adoc
> index 160c74a..8827476 100644
> --- a/riscv-platform-spec.adoc
> +++ b/riscv-platform-spec.adoc
> @@ -34,6 +34,36 @@ include::profiles.adoc[]
>  // Linux-2022 Platform
>  == Linux-2022 Platform
>
> +=== Terminology
> +[cols="1,2", width=80%, align="left", options="header"]
> +|===
> +|TERM      | DESCRIPTION
> +|SBI       | Supervisor Binary Interface
> +|UEFI      | Unified Extensible Firmware Interface
> +|ACPI      | Advanced Configuration and Power Interface
> +|SMBIOS    | System Management Basic I/O System
> +|DTS       | Devicetree source file
> +|DTB       | Devicetree binary
> +|RVA22     | RISC-V Application 2022
> +|EE        | Execution Environment
> +|RV32GC    | RISC-V 32-bit general purpose ISA described as RV32IMAFDC.
> +|RV64GC    | RISC-V 64-bit general purpose ISA described as RV64IMAFDC.
> +|===
> +
> +=== Specifications
> +[cols="1,2", width=80%, align="left", options="header"]
> +|===
> +|SPECIFICATION      | VERSION
> +|link:https://uefi.org/sites/default/files/resources/UEFI_Spec_2_9_2021_03_18.pdf[UEFI Specification]         | v2.9
> +|link:https://github.com/devicetree-org/devicetree-specification/releases/tag/v0.3[Devicetree Specification]  | v0.3
> +|link:https://github.com/riscv/riscv-sbi-doc/blob/master/riscv-sbi.adoc[SBI Specification]                    | v0.3-rc0
> +|link:[RVA22 Specification]                                                                                   | TBD
> +|link:https://arm-software.github.io/ebbr/[EBBR Specification]                                                | v2.0.0-pre1
> +|link:https://uefi.org/sites/default/files/resources/ACPI_Spec_6_4_Jan22.pdf[ACPI Specification]              | v6.4
> +|link:https://www.dmtf.org/sites/default/files/standards/documents/DSP0134_3.4.0.pdf[SMBIOS Specification]    | v3.4.0
> +|link:[Platform Policy]                                                                                       | TBD
> +|===
> +
>  // Base feature set for Linux-2022 Platform
>  === Base
>  ==== Architecture
> @@ -59,14 +89,104 @@ include::profiles.adoc[]
>  * Timers
>  * Watchdog Timers
>
> -==== Boot Process
> -* Firmware
> -* Boot-Loader
> -* Discovery Mechanisms
> +==== Boot and Runtime Requirements
> +- The base specification defines the interface between the firmware and the
> +operating system suitable for the RISC-V platforms with rich operating
> +systems.
> +- These requirements specifies the required boot and runtime services, device
> +discovery mechanism, etc.
> +- The requirements are operating system agnostic, specific firmware/bootloader
> +implementation agnostic.
> +- Any RV32GC or RV64GC platform seeking compliance with the base specification
> +require to implement all three privilege modes i.e. M, S and U mode.
> +- For the generic mandatory requirements this base specification will refer to
> +the EBBR Specification. Any deviation from the EBBR will be explicitly
> +mentioned in the requirements.
> +- Specifications followed are mentioned in the
> +<<Specifications,Specification Section>>
> +
> +
> +===== Firmware
> +- UEFI Platform is required to adhere to RISC-V Platform requirements on
> +calling conventions, ABI support specific to RISC-V. Refer Chapter - 2.3.7
> +RISC-V Platforms of UEFI specification.
> +- For compliance with base specification platform is required to implement
> +link:https://arm-software.github.io/ebbr/#required-elements[EBBR - UEFI Required Elements],
> +link:https://arm-software.github.io/ebbr/#required-platform-specific-elements[EBBR - UEFI Platform Specific Elements]
> +and following
> +link:https://arm-software.github.io/ebbr/#required-global-variables[EBBR - Global Variables].
> +
> +====== Storage and Partitioning
> +- Firmware is required to implement requirements as per the
> +link:https://arm-software.github.io/ebbr/#firmware-storage[EBBR Firmware Storage].
> +requirements.
> +- For shared storage base spec requires GPT partitioning, MBR is deprecated.

"deprecated" implies is required but will be removed in next version.
Use instead:

"MBR support is not required."

> +
> +===== Boot Services
> +- All functions defined as boot services are required. Methods for
> +unsupported or unimplemented behavior must return an appropriate error
> +code.
> +
> +====== Startup Protocol
> +- UEFI firmware could be executed in either Machine mode or Supervisor mode
> +during the entire POST, according to the hart capability and the platform
> +design. For detailed requirements on startup protocol refer link:[**TBD** - EBBR LINK FOR STARTUP PROTOCOL]
> +and UEFI chapter 2.3.7 RISC-V Platforms.
> +
> +
> +====== Memory Map
> +- Base specification requires UEFI environment to provide a system memory map
> +as per the requirements link:https://arm-software.github.io/ebbr/#memory-map[EBBR - Memory Map].
> +
> +
> +===== Discovery Mechanisms
> +- Devicetree is the required mechanism for system description.
> +- System is required to implement link:https://arm-software.github.io/ebbr/#devicetree[EBBR - Devicetree requirements]
> +to comply with this base specification. Also refer Devicetree tables section in
> +chapter - 4.6 EFI Configuration Table & Properties Table of UEFI specification.
> +
> +===== Runtime Services
> +====== SBI
>
> -==== Runtime services
> -* SBI
> -* UEFI
> +- Required SBI spec version is 0.3 or higher.
> +- Legacy Extensions from the SBI Specification are deprecated.

Please, remove this sentence because we do not require to implement
this.

Best regards

Heinrich

> +- Required SBI extensions -
> +
> +[cols="1,2", width=80%, align="left", options="header"]
> +|===
> +|EXTENSION     |    CONDITIONS
> +|SBI TIME      |    if **stimecmp** CSR not available
> +|SBI IPI       |
> +|SBI RFENCE    |
> +|SBI HSM       |
> +|SBI SRST      |
> +|SBI PMU       |
> +|===
> +
> +- Required responsibilities of M-Mode runtime also includes -
> +    ** Interrupt and Exception Delegation
> +    ** Misaligned Load & Stores handling
> +    ** Missing CSRs emulation
> +    ** PMP Configuration
> +
> +- Wherever applicable firmware must implement UEFI interfaces over similar
> +interfaces and services present in the SBI specification. For example, UEFI
> +runtime services must implement ResetSystem() via SBI Reset extension.
> +
> +====== UEFI
> +- Firmware must conform to the
> +link:https://arm-software.github.io/ebbr/#uefi-runtime-services[EBBR - UEFI EFI_RUNTIME_SERVICES requirements].
> +- Firmware must meet the requirements for
> +link:https://arm-software.github.io/ebbr/#runtime-device-mappings[EBBR - Runtime Device Mappings]
> +to avoid conflict between the firmware and OS when accessing the mapped
> +devices.
> +- Compliant UEFI runtime environment must meet the requirements for the
> +link:https://arm-software.github.io/ebbr/#runtime-variable-access[EBBR - Runtime Variable Access].
> +- Compliant implementation must meet the Realtime Clock requirements
> +link:https://arm-software.github.io/ebbr/#real-time-clock-rtc[EBBR - UEFI RTC interface]
> +if RTC is present in the system.
> +- OS should prioritize calling the UEFI interfaces before the SBI or Platform
> +specific mechanisms.
>
>  // Server extension for Linux-2022 Platform
>  === Server Extension
>