summaryrefslogtreecommitdiff
path: root/Documentation/arch/riscv
AgeCommit message (Collapse)Author
2024-07-01documentation: Fix riscv cmodx exampleCharlie Jenkins
ON/OFF in the keys was swapped between the first and second argument of the prctl. The prctl key is always PR_RISCV_SET_ICACHE_FLUSH_CTX, and the second argument can be PR_RISCV_CTX_SW_FENCEI_ON or PR_RISCV_CTX_SW_FENCEI_OFF. Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> Fixes: 6a08e4709c58 ("documentation: Document PR_RISCV_SET_ICACHE_FLUSH_CTX prctl") Link: https://lore.kernel.org/r/20240628-fix_cmodx_example-v1-1-e6c6523bc163@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-05-30Documentation: RISC-V: uabi: Only scalar misaligned loads are supportedPalmer Dabbelt
We're stuck supporting scalar misaligned loads in userspace because they were part of the ISA at the time we froze the uABI. That wasn't the case for vector misaligned accesses, so depending on them unconditionally is a userspace bug. All extant vector hardware traps on these misaligned accesses. Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20240524185600.5919-1-palmer@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-04-30Merge patch series "riscv: Create and document PR_RISCV_SET_ICACHE_FLUSH_CTX ↵Palmer Dabbelt
prctl" Charlie Jenkins <charlie@rivosinc.com> says: Improve the performance of icache flushing by creating a new prctl flag PR_RISCV_SET_ICACHE_FLUSH_CTX. The interface is left generic to allow for future expansions such as with the proposed J extension [1]. Documentation is also provided to explain the use case. Patch sent to add PR_RISCV_SET_ICACHE_FLUSH_CTX to man-pages [2]. [1] https://github.com/riscv/riscv-j-extension [2] https://lore.kernel.org/linux-man/20240124-fencei_prctl-v1-1-0bddafcef331@rivosinc.com * b4-shazam-merge: cpumask: Add assign cpu documentation: Document PR_RISCV_SET_ICACHE_FLUSH_CTX prctl riscv: Include riscv_set_icache_flush_ctx prctl riscv: Remove unnecessary irqflags processor.h include Link: https://lore.kernel.org/r/20240312-fencei-v13-0-4b6bdc2bbf32@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-04-28riscv: hwprobe: export Zihintpause ISA extensionClément Léger
Export the Zihintpause ISA extension through hwprobe which allows using "pause" instructions. Some userspace applications (OpenJDK for instance) uses this to handle some locking back-off. Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Link: https://lore.kernel.org/r/20240221083108.1235311-1-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-04-18documentation: Document PR_RISCV_SET_ICACHE_FLUSH_CTX prctlCharlie Jenkins
Provide documentation that explains how to properly do CMODX in riscv. Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240312-fencei-v13-3-4b6bdc2bbf32@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-03-14docs: riscv: Define behavior of mmapCharlie Jenkins
Define mmap on riscv to not provide an address that uses more bits than the hint address, if provided. Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240130-use_mmap_hint_address-v3-3-8a655cfa8bcb@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-17Merge tag 'docs-6.8-2' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation fixes from Jonathan Corbet: "A handful of late-arriving documentation fixes" * tag 'docs-6.8-2' of git://git.lwn.net/linux: docs, kprobes: Add loongarch as supported architecture docs, kprobes: Update email address of Masami Hiramatsu docs: admin-guide: hw_random: update rng-tools website Documentation/core-api: fix spelling mistake in workqueue docs: kernel_feat.py: fix potential command injection Documentation: constrain alabaster package to older versions
2024-01-11docs: kernel_feat.py: fix potential command injectionVegard Nossum
The kernel-feat directive passes its argument straight to the shell. This is unfortunate and unnecessary. Let's always use paths relative to $srctree/Documentation/ and use subprocess.check_call() instead of subprocess.Popen(shell=True). This also makes the code shorter. This is analogous to commit 3231dd586277 ("docs: kernel_abi.py: fix command injection") where we did exactly the same thing for kernel_abi.py, somehow I completely missed this one. Link: https://fosstodon.org/@jani/111676532203641247 Reported-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20240110174758.3680506-1-vegard.nossum@oracle.com
2024-01-09Merge patch series "riscv: hwprobe: add Zicond, Zacas and Ztso support"Palmer Dabbelt
Clément Léger <cleger@rivosinc.com> says: This series add support for a few more extensions that are present in the RVA22U64/RVA23U64 (either mandatory or optional) and that are useful for userspace: - Zicond - Zacas - Ztso Series currently based on riscv/for-next. * b4-shazam-lts: riscv: hwprobe: export Zicond extension riscv: hwprobe: export Zacas ISA extension riscv: add ISA extension parsing for Zacas dt-bindings: riscv: add Zacas ISA extension description riscv: hwprobe: export Ztso ISA extension riscv: add ISA extension parsing for Ztso Link: https://lore.kernel.org/r/20231220155723.684081-1-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09riscv: hwprobe: export Zicond extensionClément Léger
Export the zicond extension to userspace using hwprobe. Signed-off-by: Clément Léger <cleger@rivosinc.com> Link: https://lore.kernel.org/r/20231220155723.684081-7-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09riscv: hwprobe: export Zacas ISA extensionClément Léger
Export Zacas ISA extension through hwprobe. Signed-off-by: Clément Léger <cleger@rivosinc.com> Link: https://lore.kernel.org/r/20231220155723.684081-6-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09riscv: hwprobe: export Ztso ISA extensionClément Léger
Export the Ztso extension to userspace. Signed-off-by: Clément Léger <cleger@rivosinc.com> Link: https://lore.kernel.org/r/20231220155723.684081-3-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-09Merge patch series "RISC-V: hwprobe: Introduce which-cpus"Palmer Dabbelt
Andrew Jones <ajones@ventanamicro.com> says: This series introduces a flag for the hwprobe syscall which effectively reverses its behavior from getting the values of keys for a set of cpus to getting the cpus for a set of key-value pairs. * b4-shazam-merge: RISC-V: selftests: Add which-cpus hwprobe test RISC-V: hwprobe: Introduce which-cpus flag RISC-V: Move the hwprobe syscall to its own file RISC-V: hwprobe: Clarify cpus size parameter Link: https://lore.kernel.org/r/20231122164700.127954-6-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-03RISC-V: hwprobe: Introduce which-cpus flagAndrew Jones
Introduce the first flag for the hwprobe syscall. The flag basically reverses its behavior, i.e. instead of populating the values of keys for a given set of cpus, the set of cpus after the call is the result of finding a set which supports the values of the keys. In order to do this, we implement a pair compare function which takes the type of value (a single value vs. a bitmask of booleans) into consideration. We also implement vdso support for the new flag. Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20231122164700.127954-9-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-01-03RISC-V: hwprobe: Clarify cpus size parameterAndrew Jones
The "count" parameter associated with the 'cpus' parameter of the hwprobe syscall is the size in bytes of 'cpus'. Naming it 'cpu_count' may mislead users (it did me) to think it's the number of CPUs that are or can be represented by 'cpus' instead. This is particularly easy (IMO) to get wrong since 'cpus' is documented to be defined by CPU_SET(3) and CPU_SET(3) also documents a CPU_COUNT() (the number of CPUs in set) macro. CPU_SET(3) refers to the size of cpu sets with 'setsize'. Adopt 'cpusetsize' for the hwprobe parameter and specifically state it is in bytes in Documentation/riscv/hwprobe.rst to clarify. Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20231122164700.127954-7-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12riscv: hwprobe: export Zfa ISA extensionClément Léger
Export Zfa ISA extension[1] through hwprobe. Link: https://drive.google.com/file/d/1VT6QIggpb59-8QRV266dEE4T8FZTxGq4/view [1] Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20231114141256.126749-20-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12riscv: hwprobe: export Zvfh[min] ISA extensionsClément Léger
Export Zvfh[min] ISA extension[1] through hwprobe. Link: https://drive.google.com/file/d/1_Yt60HGAf1r1hx7JnsIptw0sqkBd9BQ8/view [1] Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20231114141256.126749-17-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12riscv: hwprobe: export Zhintntl ISA extensionClément Léger
Export Zihintntl extension[1] through hwprobe. Link: https://drive.google.com/file/d/13_wsN8YmRfH8YWysFyTX-DjTkCnBd9hj/view [1] Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20231114141256.126749-14-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12riscv: hwprobe: export Zfh[min] ISA extensionsClément Léger
Export Zfh[min] ISA extensions[1] through hwprobe only if FPU support is available. Link: https://drive.google.com/file/d/1z3tQQLm5ALsAD77PM0l0CHnapxWCeVzP/view [1] Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20231114141256.126749-11-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12riscv: hwprobe: export vector crypto ISA extensionsClément Léger
Export Zv* vector crypto ISA extensions that were added in "RISC-V Cryptography Extensions Volume II" specification[1] through hwprobe. This adds support for the following instructions: - Zvbb: Vector Basic Bit-manipulation - Zvbc: Vector Carryless Multiplication - Zvkb: Vector Cryptography Bit-manipulation - Zvkg: Vector GCM/GMAC. - Zvkned: NIST Suite: Vector AES Block Cipher - Zvknh[ab]: NIST Suite: Vector SHA-2 Secure Hash - Zvksed: ShangMi Suite: SM4 Block Cipher - Zvksh: ShangMi Suite: SM3 Secure Hash - Zvknc: NIST Algorithm Suite with carryless multiply - Zvkng: NIST Algorithm Suite with GCM. - Zvksc: ShangMi Algorithm Suite with carryless multiplication - Zvksg: ShangMi Algorithm Suite with GCM. - Zvkt: Vector Data-Independent Execution Latency. Zvkn and Zvks are ommited since they are a superset of other extensions. Link: https://drive.google.com/file/d/1gb9OLH-DhbCgWp7VwpPOVrrY6f3oSJLL/view [1] Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20231114141256.126749-8-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12riscv: hwprobe: add support for scalar crypto ISA extensionsClément Léger
Export the following scalar crypto extensions through hwprobe: - Zbkb - Zbkc - Zbkx - Zknd - Zkne - Zknh - Zksed - Zksh - Zkt Signed-off-by: Clément Léger <cleger@rivosinc.com> Link: https://lore.kernel.org/r/20231114141256.126749-5-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-12-12riscv: hwprobe: export missing Zbc ISA extensionClément Léger
While Zba and Zbb were exported through hwprobe, Zbc was not. Export it. Signed-off-by: Clément Léger <cleger@rivosinc.com> Link: https://lore.kernel.org/r/20231114141256.126749-3-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-11-10Merge tag 'riscv-for-linus-6.7-mw2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull more RISC-V updates from Palmer Dabbelt: - Support for handling misaligned accesses in S-mode - Probing for misaligned access support is now properly cached and handled in parallel - PTDUMP now reflects the SW reserved bits, as well as the PBMT and NAPOT extensions - Performance improvements for TLB flushing - Support for many new relocations in the module loader - Various bug fixes and cleanups * tag 'riscv-for-linus-6.7-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits) riscv: Optimize bitops with Zbb extension riscv: Rearrange hwcap.h and cpufeature.h drivers: perf: Do not broadcast to other cpus when starting a counter drivers: perf: Check find_first_bit() return value of: property: Add fw_devlink support for msi-parent RISC-V: Don't fail in riscv_of_parent_hartid() for disabled HARTs riscv: Fix set_memory_XX() and set_direct_map_XX() by splitting huge linear mappings riscv: Don't use PGD entries for the linear mapping RISC-V: Probe misaligned access speed in parallel RISC-V: Remove __init on unaligned_emulation_finish() RISC-V: Show accurate per-hart isa in /proc/cpuinfo RISC-V: Don't rely on positional structure initialization riscv: Add tests for riscv module loading riscv: Add remaining module relocations riscv: Avoid unaligned access when relocating modules riscv: split cache ops out of dma-noncoherent.c riscv: Improve flush_tlb_kernel_range() riscv: Make __flush_tlb_range() loop over pte instead of flushing the whole tlb riscv: Improve flush_tlb_range() for hugetlb pages riscv: Improve tlb_flush() ...
2023-11-08Merge tag 'riscv-for-linus-6.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for cbo.zero in userspace - Support for CBOs on ACPI-based systems - A handful of improvements for the T-Head cache flushing ops - Support for software shadow call stacks - Various cleanups and fixes * tag 'riscv-for-linus-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (31 commits) RISC-V: hwprobe: Fix vDSO SIGSEGV riscv: configs: defconfig: Enable configs required for RZ/Five SoC riscv: errata: prefix T-Head mnemonics with th. riscv: put interrupt entries into .irqentry.text riscv: mm: Update the comment of CONFIG_PAGE_OFFSET riscv: Using TOOLCHAIN_HAS_ZIHINTPAUSE marco replace zihintpause riscv/mm: Fix the comment for swap pte format RISC-V: clarify the QEMU workaround in ISA parser riscv: correct pt_level name via pgtable_l5/4_enabled RISC-V: Provide pgtable_l5_enabled on rv32 clocksource: timer-riscv: Increase rating of clock_event_device for Sstc clocksource: timer-riscv: Don't enable/disable timer interrupt lkdtm: Fix CFI_BACKWARD on RISC-V riscv: Use separate IRQ shadow call stacks riscv: Implement Shadow Call Stack riscv: Move global pointer loading to a macro riscv: Deduplicate IRQ stack switching riscv: VMAP_STACK overflow detection thread-safe RISC-V: cacheflush: Initialize CBO variables on ACPI systems RISC-V: ACPI: RHCT: Add function to get CBO block sizes ...
2023-10-10docs: move riscv under archCosta Shulyupin
and fix all in-tree references. Architecture-specific documentation is being moved into Documentation/arch/ as a way of cleaning up the top-level documentation directory and making the docs hierarchy more closely match the source hierarchy. Signed-off-by: Costa Shulyupin <costa.shul@redhat.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20230930185354.3034118-1-costa.shul@redhat.com