Resolve riscv-non-isa#118

Remove SRST requirement. It doesn't matter how SystemReset is implemented,
we're only concerned with it being the only mechanism used by a BRS-I
OS.

What about BRS-B? Well it can choose to do whatever, which (most likely)
will mean using SRST. A particular BRS-B implementation may impose any number
of additional requirements not actually present in the BRS spec.

Signed-off-by: Andrei Warkentin <[email protected]>

sbi.adoc

@@ -12,9 +12,7 @@ privilege mode in order to be compatible with this specification.
 | ID#     ^| Requirement
 | SBI_010  | The SBI implementation MUST conform to SBI v2.0 or later.
 | SBI_020  | The SBI implementation MUST implement the Hart State Management (HSM) extension.
-2+| _HSM is used by an OS for starting up, stopping, suspending and querying the status of secondary harts.
-| SBI_030  | The System Reset (SRST) extension MUST be implemented.
-2+| _See <<uefi-resetsystem, UEFI requirements>> for additional notes on SRST use by a UEFI and OS._
+2+| _HSM is used by an OS for starting up, stopping, suspending and querying the status of secondary harts._
 |===
 
 Certain requirements are conditional on the presence of RISC-V ISA extensions or system features.
@@ -23,9 +21,9 @@ Certain requirements are conditional on the presence of RISC-V ISA extensions or
 [%header, cols="5,25"]
 |===
 | ID#     ^| Requirement
-| SBI_040  | The Timer (TIME) extension MUST be implemented, if the RISC-V "stimecmp / vstimecmp" Extension (Sstc) cite: [Sstc] is not available.
-| SBI_050  | The S-Mode IPI (IPI) extension MUST be implemented, if the Incoming MSI Controller (IMSIC) cite: [Aia] is not available.
-| SBI_060  | The RFENCE (RFNC) extension MUST be implemented, if the Incoming MSI Controller (IMSIC) cite: [Aia] is not available.
-| SBI_070  | The Performance Monitoring (PMU) extension MUST be implemented, if the counter delegation-related ISA extensions (S*csrind cite: [Sscsrind], Smcdeleg cite: [Smcdeleg], Ssccfg cite: [Smcdeleg]) are not present.
+| SBI_030  | The Timer (TIME) extension MUST be implemented, if the RISC-V "stimecmp / vstimecmp" Extension (Sstc) cite: [Sstc] is not available.
+| SBI_040  | The S-Mode IPI (IPI) extension MUST be implemented, if the Incoming MSI Controller (IMSIC) cite: [Aia] is not available.
+| SBI_050  | The RFENCE (RFNC) extension MUST be implemented, if the Incoming MSI Controller (IMSIC) cite: [Aia] is not available.
+| SBI_060  | The Performance Monitoring (PMU) extension MUST be implemented, if the counter delegation-related ISA extensions (S*csrind cite: [Sscsrind], Smcdeleg cite: [Smcdeleg], Ssccfg cite: [Smcdeleg]) are not present.
 2+| _NOTE: The PMU extension is currently being developed by the performance analysis TG cite: [PerfAnalysis]._
 |===

uefi.adoc

@@ -72,17 +72,8 @@ See additional <<uefi-rt, requirements under UEFI Runtime Services>>.
              * GetTime and SetTime must return EFI_UNSUPPORTED, when called after the UEFI boot services have been exited.
              * GetTime and SetTime must be appropriately described in EFI_RT_PROPERTIES_TABLE.
 2+|_Also see <<acpi-tad, AML_070>>_.
-| [[uefi-resetsystem]] URT_030 a| The UEFI ResetSystem() runtime service MUST be implemented using the SBI SRST extension. The following table maps the UEFI RT and SRST call parameters:
-[width=100%]
-[%header]
-!===
-!ResetSystem() ResetType ^! sbi_system_reset type
-!EfiResetShutdown ! 0x00000000 (Shutdown)
-!EfiResetCold ! 0x00000001 (Cold reboot)
-!EfiResetWarm ! 0x00000002 (Warm reboot)
-!EfiResetPlatformSpecific ! 0xF0000000 - 0xFFFFFFFF (Vendor or system-specific reset type)
-!===
-2+| _The OS MUST call the ResetSystem() runtime service call to reset or shutdown the system, preferring this to SBI SRST, ACPI or other system-specific mechanisms. This allows for systems to perform any required system tasks on the way out (e.g. servicing UpdateCapsule() or persisting non-volatile variables in some systems)._
+| URT_030 a| The UEFI ResetSystem() runtime service MUST be implemented.
+2+| _The OS MUST call the ResetSystem() runtime service call to reset or shutdown the system, preferring this to SBI, ACPI or other system-specific mechanisms. This allows for systems to perform any required system tasks on the way out (e.g. servicing UpdateCapsule() or persisting non-volatile variables in some systems)._
 | URT_040 | Non-volatile UEFI variables MUST persist across calls to the Reset System() runtime service call.
 | URT_050 | UEFI Runtime Services MUST be able to update the variables directly without the aid of an OS.
 | URT_060 a| The following requirements MUST be met for systems with UEFI Secure Boot: