diff options
Diffstat (limited to 'Documentation/arch')
| -rw-r--r-- | Documentation/arch/arm64/booting.rst | 8 | ||||
| -rw-r--r-- | Documentation/arch/arm64/sve.rst | 5 | ||||
| -rw-r--r-- | Documentation/arch/riscv/hwprobe.rst | 11 | ||||
| -rw-r--r-- | Documentation/arch/s390/s390dbf.rst | 5 | ||||
| -rw-r--r-- | Documentation/arch/x86/boot.rst | 40 |
5 files changed, 52 insertions, 17 deletions
diff --git a/Documentation/arch/arm64/booting.rst b/Documentation/arch/arm64/booting.rst index e4f953839f71..26efca09aef3 100644 --- a/Documentation/arch/arm64/booting.rst +++ b/Documentation/arch/arm64/booting.rst @@ -391,13 +391,13 @@ Before jumping into the kernel, the following conditions must be met: - SMCR_EL2.LEN must be initialised to the same value for all CPUs the kernel will execute on. - - HWFGRTR_EL2.nTPIDR2_EL0 (bit 55) must be initialised to 0b01. + - HFGRTR_EL2.nTPIDR2_EL0 (bit 55) must be initialised to 0b01. - - HWFGWTR_EL2.nTPIDR2_EL0 (bit 55) must be initialised to 0b01. + - HFGWTR_EL2.nTPIDR2_EL0 (bit 55) must be initialised to 0b01. - - HWFGRTR_EL2.nSMPRI_EL1 (bit 54) must be initialised to 0b01. + - HFGRTR_EL2.nSMPRI_EL1 (bit 54) must be initialised to 0b01. - - HWFGWTR_EL2.nSMPRI_EL1 (bit 54) must be initialised to 0b01. + - HFGWTR_EL2.nSMPRI_EL1 (bit 54) must be initialised to 0b01. For CPUs with the Scalable Matrix Extension FA64 feature (FEAT_SME_FA64): diff --git a/Documentation/arch/arm64/sve.rst b/Documentation/arch/arm64/sve.rst index 28152492c29c..a61c9d0efe4d 100644 --- a/Documentation/arch/arm64/sve.rst +++ b/Documentation/arch/arm64/sve.rst @@ -402,6 +402,11 @@ The regset data starts with struct user_sve_header, containing: streaming mode and any SETREGSET of NT_ARM_SSVE will enter streaming mode if the target was not in streaming mode. +* On systems that do not support SVE it is permitted to use SETREGSET to + write SVE_PT_REGS_FPSIMD formatted data via NT_ARM_SVE, in this case the + vector length should be specified as 0. This allows streaming mode to be + disabled on systems with SME but not SVE. + * If any register data is provided along with SVE_PT_VL_ONEXEC then the registers data will be interpreted with the current vector length, not the vector length configured for use on exec. diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst index 2f449c9b15bd..06c5280b728a 100644 --- a/Documentation/arch/riscv/hwprobe.rst +++ b/Documentation/arch/riscv/hwprobe.rst @@ -249,6 +249,9 @@ The following keys are defined: defined in the in the RISC-V ISA manual starting from commit e87412e621f1 ("integrate Zaamo and Zalrsc text (#1304)"). + * :c:macro:`RISCV_HWPROBE_EXT_ZALASR`: The Zalasr extension is supported as + frozen at commit 194f0094 ("Version 0.9 for freeze") of riscv-zalasr. + * :c:macro:`RISCV_HWPROBE_EXT_ZALRSC`: The Zalrsc extension is supported as defined in the in the RISC-V ISA manual starting from commit e87412e621f1 ("integrate Zaamo and Zalrsc text (#1304)"). @@ -275,6 +278,9 @@ The following keys are defined: ratified in commit 49f49c842ff9 ("Update to Rafified state") of riscv-zabha. + * :c:macro:`RISCV_HWPROBE_EXT_ZICBOP`: The Zicbop extension is supported, as + ratified in commit 3dd606f ("Create cmobase-v1.0.pdf") of riscv-CMOs. + * :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: Deprecated. Returns similar values to :c:macro:`RISCV_HWPROBE_KEY_MISALIGNED_SCALAR_PERF`, but the key was mistakenly classified as a bitmask rather than a value. @@ -369,4 +375,7 @@ The following keys are defined: * :c:macro:`RISCV_HWPROBE_VENDOR_EXT_XSFVFWMACCQQQ`: The Xsfvfwmaccqqq vendor extension is supported in version 1.0 of Matrix Multiply Accumulate - Instruction Extensions Specification.
\ No newline at end of file + Instruction Extensions Specification. + +* :c:macro:`RISCV_HWPROBE_KEY_ZICBOP_BLOCK_SIZE`: An unsigned int which + represents the size of the Zicbop block in bytes. diff --git a/Documentation/arch/s390/s390dbf.rst b/Documentation/arch/s390/s390dbf.rst index af8bdc3629e7..aad6d88974fe 100644 --- a/Documentation/arch/s390/s390dbf.rst +++ b/Documentation/arch/s390/s390dbf.rst @@ -243,9 +243,8 @@ Examples: Changing the size of debug areas ------------------------------------ -It is possible the change the size of debug areas through piping -the number of pages to the debugfs file "pages". The resize request will -also flush the debug areas. +To resize a debug area, write the desired page count to the "pages" file. +Existing data is preserved if it fits; otherwise, oldest entries are dropped. Example: diff --git a/Documentation/arch/x86/boot.rst b/Documentation/arch/x86/boot.rst index 77e6163288db..32eea3d2807e 100644 --- a/Documentation/arch/x86/boot.rst +++ b/Documentation/arch/x86/boot.rst @@ -1431,12 +1431,34 @@ The boot loader *must* fill out the following fields in bp:: All other fields should be zero. .. note:: - The EFI Handover Protocol is deprecated in favour of the ordinary PE/COFF - entry point, combined with the LINUX_EFI_INITRD_MEDIA_GUID based initrd - loading protocol (refer to [0] for an example of the bootloader side of - this), which removes the need for any knowledge on the part of the EFI - bootloader regarding the internal representation of boot_params or any - requirements/limitations regarding the placement of the command line - and ramdisk in memory, or the placement of the kernel image itself. - -[0] https://github.com/u-boot/u-boot/commit/ec80b4735a593961fe701cc3a5d717d4739b0fd0 + The EFI Handover Protocol is deprecated in favour of the ordinary PE/COFF + entry point described below. + +.. _pe-coff-entry-point: + +PE/COFF entry point +=================== + +When compiled with ``CONFIG_EFI_STUB=y``, the kernel can be executed as a +regular PE/COFF binary. See Documentation/admin-guide/efi-stub.rst for +implementation details. + +The stub loader can request the initrd via a UEFI protocol. For this to work, +the firmware or bootloader needs to register a handle which carries +implementations of the ``EFI_LOAD_FILE2`` protocol and the device path +protocol exposing the ``LINUX_EFI_INITRD_MEDIA_GUID`` vendor media device path. +In this case, a kernel booting via the EFI stub will invoke +``LoadFile2::LoadFile()`` method on the registered protocol to instruct the +firmware to load the initrd into a memory location chosen by the kernel/EFI +stub. + +This approach removes the need for any knowledge on the part of the EFI +bootloader regarding the internal representation of boot_params or any +requirements/limitations regarding the placement of the command line and +ramdisk in memory, or the placement of the kernel image itself. + +For sample implementations, refer to `the original u-boot implementation`_ or +`the OVMF implementation`_. + +.. _the original u-boot implementation: https://github.com/u-boot/u-boot/commit/ec80b4735a593961fe701cc3a5d717d4739b0fd0 +.. _the OVMF implementation: https://github.com/tianocore/edk2/blob/1780373897f12c25075f8883e073144506441168/OvmfPkg/LinuxInitrdDynamicShellCommand/LinuxInitrdDynamicShellCommand.c |