summaryrefslogtreecommitdiff
path: root/arch/riscv/kernel
AgeCommit message (Collapse)AuthorFilesLines
2023-06-26riscv: vmlinux-xip.lds.S: remove .alternative sectionJisheng Zhang1-6/+0
ALTERNATIVE mechanism can't work on XIP, and this is also reflected by below Kconfig dependency: RISCV_ALTERNATIVE ... depends on !XIP_KERNEL ... So there's no .alternative section at all for XIP case, remove it. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Guo Ren <guoren@kernel.org> Tested-by: Nick Desaulniers <ndesaulniers@google.com> # build Link: https://lore.kernel.org/r/20230523165502.2592-3-jszhang@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-23riscv: hibernate: remove WARN_ON in save_processor_stateSong Shuai1-1/+0
During hibernation or restoration, freeze_secondary_cpus checks num_online_cpus via BUG_ON, and the subsequent save_processor_state also does the checking with WARN_ON. In the case of CONFIG_PM_SLEEP_SMP=n, freeze_secondary_cpus is not defined, but the sole possible condition to disable CONFIG_PM_SLEEP_SMP is !SMP where num_online_cpus is always 1. We also don't have to check it in save_processor_state. So remove the unnecessary checking in save_processor_state. Fixes: c0317210012e ("RISC-V: Add arch functions to support hibernation/suspend-to-disk") Signed-off-by: Song Shuai <songshuaishuai@tinylab.org> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230609075049.2651723-4-songshuaishuai@tinylab.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-23Merge patch series "riscv: Add independent irq/softirq stacks support"Palmer Dabbelt2-2/+101
guoren@kernel.org <guoren@kernel.org> says: From: Guo Ren <guoren@linux.alibaba.com> This patch series adds independent irq/softirq stacks to decrease the press of the thread stack. Also, add a thread STACK_SIZE config for users to adjust the proper size during compile time. * b4-shazam-merge: riscv: stack: Add config of thread stack size riscv: stack: Support HAVE_SOFTIRQ_ON_OWN_STACK riscv: stack: Support HAVE_IRQ_EXIT_ON_IRQ_STACK Link: https://lore.kernel.org/r/20230614013018.2168426-1-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-23Merge patch series "ISA string parser cleanups"Palmer Dabbelt3-28/+116
Conor Dooley <conor@kernel.org> says: From: Conor Dooley <conor.dooley@microchip.com> Here are some bits that were discussed with Drew on the "should we allow caps" threads that I have now created patches for: - splitting of riscv_of_processor_hartid() into two distinct functions, one for use purely during early boot, prior to the establishment of the possible-cpus mask & another to fit the other current use-cases - that then allows us to then completely skip some validation of the hartid in the parser - the biggest diff in the series is a rework of the comments in the parser, as I have mostly found the existing (sparse) ones to not be all that helpful whenever I have to go back and look at it - from writing the comments, I found a conditional doing a bit of a dance that I found counter-intuitive, so I've had a go at making that match what I would expect a little better - `i` implies 4 other extensions, so add them as extensions and set them for the craic. Sure why not like... * b4-shazam-merge: RISC-V: always report presence of extensions formerly part of the base ISA dt-bindings: riscv: explicitly mention assumption of Zicntr & Zihpm support RISC-V: remove decrement/increment dance in ISA string parser RISC-V: rework comments in ISA string parser RISC-V: validate riscv,isa at boot, not during ISA string parsing RISC-V: split early & late of_node to hartid mapping RISC-V: simplify register width check in ISA string parsing Link: https://lore.kernel.org/r/20230607-audacity-overhaul-82bb867a825f@spud Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-22riscv: stack: Support HAVE_SOFTIRQ_ON_OWN_STACKGuo Ren1-0/+35
Add the HAVE_SOFTIRQ_ON_OWN_STACK feature for the IRQ_STACKS config, and the irq and softirq use the same irq_stack of percpu. Tested-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Link: https://lore.kernel.org/r/20230614013018.2168426-3-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-22riscv: stack: Support HAVE_IRQ_EXIT_ON_IRQ_STACKGuo Ren2-2/+66
Add independent irq stacks for percpu to prevent kernel stack overflows. It is also compatible with VMAP_STACK by arch_alloc_vmap_stack. Tested-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Cc: Clément Léger <cleger@rivosinc.com> Link: https://lore.kernel.org/r/20230614013018.2168426-2-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-22riscv: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVALDonglin Peng1-6/+1
The previous patch ("function_graph: Support recording and printing the return value of function") has laid the groundwork for the for the funcgraph-retval, and this modification makes it available on the RISC-V platform. We introduce a new structure called fgraph_ret_regs for the RISC-V platform to hold return registers and the frame pointer. We then fill its content in the return_to_handler and pass its address to the function ftrace_return_to_handler to record the return value. Link: https://lore.kernel.org/linux-trace-kernel/a8d71b12259f90e7e63d0ea654fcac95b0232bbc.1680954589.git.pengdonglin@sangfor.com.cn Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-06-21RISC-V: always report presence of extensions formerly part of the base ISAConor Dooley2-0/+21
Of these four extensions, two were part of the base ISA when the port was written and are required by the kernel. The other two are implied when `i` is in riscv,isa on DT systems. There's not much that userspace can do with this extra information, but there is no harm in reporting an ISA string that closer resembles the current versions of the specifications either. Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230607-nest-collision-5796b6be8be6@spud Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-21RISC-V: remove decrement/increment dance in ISA string parserConor Dooley1-8/+6
While expanding on the comments in the ISA string parsing code, I noticed that the conditional decrement of `isa` at the end of the loop was a bit odd. The parsing code expects that at the start of the for loop, `isa` will point to the first character of the next unparsed extension. However, depending on what the next extension is, this may not be true. Unless the next extension is a multi-letter extension preceded by an underscore, `isa` will either point to the string's null-terminator or to the first character of the next extension, once the switch statement has been evaluated. Obviously incrementing `isa` at the end of the loop could cause it to increment past the null terminator or miss a single letter extension, so `isa` is conditionally decremented, just so that the loop can increment it again. It's easier to understand the code if, instead of this decrement + increment dance, we instead use a while loop & rely on the handling of individual extension types to leave `isa` pointing to the first character of the next extension. As already mentioned, this won't be the case where the following extension is multi-letter & preceded by an underscore. To handle that, invert the check and increment rather than decrement. Hopefully this eliminates a "huh?!?" moment the next time somebody tries to understand this code. Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Sunil V L <sunilvl@ventanamicro.com> Link: https://lore.kernel.org/r/20230607-estate-left-f20faabefb89@spud Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-21RISC-V: rework comments in ISA string parserConor Dooley1-11/+59
I have found these comments to not be at all helpful whenever I look at the parser. Further, the comments in the default case (single letter parser) are not quite right either. Group the comments into a larger one at the start of each case, that attempts to explain things at a higher level. Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230607-headpiece-tannery-83ed5cc4856a@spud Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-21RISC-V: validate riscv,isa at boot, not during ISA string parsingConor Dooley2-9/+11
Since riscv_fill_hwcap() now only iterates over possible cpus, the basic validation of whether riscv,isa contains "rv<width>" can be moved to riscv_early_of_processor_hartid(). Further, "ima" support is required by the kernel, so reject any CPU not fitting the bill. Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Sunil V L <sunilvl@ventanamicro.com> Link: https://lore.kernel.org/r/20230607-guts-blurry-67e711acf328@spud Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-21RISC-V: split early & late of_node to hartid mappingConor Dooley2-2/+22
Some back and forth with Drew [1] about riscv_fill_hwcap() resulted in the realisation that it is not very useful to parse the DT & perform validation of riscv,isa every time we would like to get the id for a hart. Although it is no longer called in riscv_fill_hwcap(), riscv_of_processor_hartid() is called in several other places. Notably in setup_smp() it forms part of the logic for filling the mask of possible CPUs. Since a possible CPU must have passed this basic validation of riscv,isa, a repeat validation is not required. Rename riscv_of_processor_id() to riscv_early_of_processor_id(), which will be called from setup_smp() & introduce a new riscv_of_processor_id() which makes use of the pre-populated mask of possible cpus. Link: https://lore.kernel.org/linux-riscv/xvdswl3iyikwvamny7ikrxo2ncuixshtg3f6uucjahpe3xpc5c@ud4cz4fkg5dj/ [1] Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Sunil V L <sunilvl@ventanamicro.com> Link: https://lore.kernel.org/r/20230607-glade-pastel-d8cbd9d9f3c6@spud Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-21RISC-V: simplify register width check in ISA string parsingConor Dooley1-8/+7
Saving off the `isa` pointer to a temp variable, followed by checking if it has been incremented is a bit of an odd pattern. Perhaps it was done to avoid a funky looking if statement mixed with the ifdeffery. Now that we use IS_ENABLED() here just return from the parser as soon as we detect a mismatch between the string and the currently running kernel. Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Sunil V L <sunilvl@ventanamicro.com> Link: https://lore.kernel.org/r/20230607-splatter-bacterium-a75bb9f0d0b7@spud Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-20riscv: replace deprecated scall with ecallFangrui Song2-2/+2
scall is a deprecated alias for ecall. ecall is used in several places, so there is no assembler compatibility concern. Signed-off-by: Fangrui Song <maskray@google.com> Link: https://lore.kernel.org/r/20230423223210.126948-1-maskray@google.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-20riscv: uprobes: Restore thread.bad_causeTiezhu Yang1-0/+2
thread.bad_cause is saved in arch_uprobe_pre_xol(), it should be restored in arch_uprobe_{post,abort}_xol() accordingly, otherwise the save operation is meaningless, this change is similar with x86 and powerpc. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Acked-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Guo Ren <guoren@kernel.org> Fixes: 74784081aac8 ("riscv: Add uprobes supported") Link: https://lore.kernel.org/r/1682214146-3756-1-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-20Merge patch series "RISC-V: Export Zba, Zbb to usermode via hwprobe"Palmer Dabbelt3-16/+56
Evan Green <evan@rivosinc.com> says: This change detects the presence of Zba, Zbb, and Zbs extensions and exports them per-hart to userspace via the hwprobe mechanism. Glibc can then use these in setting up hwcaps-based library search paths. There's a little bit of extra housekeeping here: the first change adds Zba and Zbs to the set of extensions the kernel recognizes, and the second change starts tracking ISA features per-hart (in addition to the ANDed mask of features across all harts which the kernel uses to make decisions). Now that we track the ISA information per-hart, we could even fix up /proc/cpuinfo to accurately report extension per-hart, though I've left that out of this series for now. * b4-shazam-merge: RISC-V: hwprobe: Expose Zba, Zbb, and Zbs RISC-V: Track ISA extensions per hart RISC-V: Add Zba, Zbs extension probing Link: https://lore.kernel.org/r/20230509182504.2997252-1-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-19RISC-V: hwprobe: Expose Zba, Zbb, and ZbsEvan Green1-7/+41
Add two new bits to the IMA_EXT_0 key for ZBA, ZBB, and ZBS extensions. These are accurately reported per CPU. Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230509182504.2997252-4-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-19RISC-V: Track ISA extensions per hartEvan Green1-6/+12
The kernel maintains a mask of ISA extensions ANDed together across all harts. Let's also keep a bitmap of ISA extensions for each CPU. Although the kernel is currently unlikely to enable a feature that exists only on some CPUs, we want the ability to report asymmetric CPU extensions accurately to usermode. Note that riscv_fill_hwcaps() runs before the per_cpu_offsets are built, which is why I've used a [NR_CPUS] array rather than per_cpu() data. Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230509182504.2997252-3-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-19RISC-V: Add Zba, Zbs extension probingEvan Green2-0/+4
Add the Zba address bit manipulation extension and Zbs single bit instructions extension into those the kernel is aware of and maintains in its riscv_isa bitmap. Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230509182504.2997252-2-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-19RISC-V: ACPI : Fix for usage of pointers in different address spaceSunil V L1-2/+2
The arch specific __acpi_map_table can be wrapper around either early_memremap or early_ioremap. But early_memremap routine works with normal pointers whereas __acpi_map_table expects pointers in iomem address space. This causes kernel test bot to fail while using the sparse tool. Fix the issue by using early_ioremap and similar fix done for __acpi_unmap_table. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202305201427.I7QhPjNW-lkp@intel.com/ Fixes: a91a9ffbd3a5 ("RISC-V: Add support to build the ACPI core") Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230607112417.782085-2-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-19riscv: hibernation: Remove duplicate call of suspend_restore_csrsSong Shuai1-1/+0
The suspend_restore_csrs is called in both __hibernate_cpu_resume and the `else` of subsequent swsusp_arch_suspend. Removing the first call makes both suspend_{save,restore}_csrs left in swsusp_arch_suspend for clean code. Fixes: c0317210012e ("RISC-V: Add arch functions to support hibernation/suspend-to-disk") Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: JeeHeng Sia <jeeheng.sia@starfivetech.com> Signed-off-by: Song Shuai <songshuaishuai@tinylab.org> Link: https://lore.kernel.org/r/20230522025020.285042-1-songshuaishuai@tinylab.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-19riscv: hibernation: Replace jalr with jr before suspend_restore_regsSong Shuai1-2/+2
No need to link the x1/ra reg via jalr before suspend_restore_regs So it's better to replace jalr with jr. Signed-off-by: Song Shuai <suagrfillet@gmail.com> Reviewed-by: JeeHeng Sia <jeeheng.sia@starfivetech.com > Link: https://lore.kernel.org/r/20230519060854.214138-1-suagrfillet@gmail.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-14riscv: say disabling zicbom if no or bad riscv,cbom-block-size foundBen Dooks1-2/+2
If Zicbom is present but there was no riscv,cbom-blocks-size property found during the cpu feeatures probe, or the cbom-block-size is not valid, then the extension will be disabled. Make the print explicitly say this is disabled to ensure that there is no confusion about what is being done. Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20230317134512.254627-1-ben.dooks@codethink.co.uk Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08Merge patch series "riscv: Add vector ISA support"Palmer Dabbelt12-41/+658
Andy Chiu <andy.chiu@sifive.com> says: This is the v21 patch series for adding Vector extension support in Linux. Please refer to [1] for the introduction of the patchset. The v21 patch series was aimed to solve build issues from v19, provide usage guideline for the prctl interface, and address review comments on v20. Thank every one who has been reviewing, suggesting on the topic. Hope this get a step closer to the final merge. * b4-shazam-merge: (27 commits) selftests: add .gitignore file for RISC-V hwprobe selftests: Test RISC-V Vector prctl interface riscv: Add documentation for Vector riscv: Enable Vector code to be built riscv: detect assembler support for .option arch riscv: Add sysctl to set the default vector rule for new processes riscv: Add prctl controls for userspace vector management riscv: hwcap: change ELF_HWCAP to a function riscv: KVM: Add vector lazy save/restore support riscv: kvm: Add V extension to KVM ISA riscv: prevent stack corruption by reserving task_pt_regs(p) early riscv: signal: validate altstack to reflect Vector riscv: signal: Report signal frame size to userspace via auxv riscv: signal: Add sigcontext save/restore for vector riscv: signal: check fp-reserved words unconditionally riscv: Add ptrace vector support riscv: Allocate user's vector context in the first-use trap riscv: Add task switch support for vector riscv: Introduce struct/helpers to save/restore per-task Vector state riscv: Introduce riscv_v_vsize to record size of Vector context ... Link: https://lore.kernel.org/r/20230605110724.21391-1-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Add sysctl to set the default vector rule for new processesAndy Chiu1-1/+32
To support Vector extension, the series exports variable-length vector registers on the signal frame. However, this potentially breaks abi if processing vector registers is required in the signal handler for old binaries. For example, there is such need if user-level context switch is triggerred via signals[1]. For this reason, it is best to leave a decision to distro maintainers, where the enablement of userspace Vector for new launching programs can be controlled. Developers may also need the switch to experiment with. The parameter is configurable through sysctl interface so a distro may turn off Vector early at init script if the break really happens in the wild. The switch will only take effects on new execve() calls once set. This will not effect existing processes that do not call execve(), nor processes which has been set with a non-default vstate_ctrl by making explicit PR_RISCV_V_SET_CONTROL prctl() calls. Link: https://lore.kernel.org/all/87cz4048rp.fsf@all.your.base.are.belong.to.us/ Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Greentime Hu <greentime.hu@sifive.com> Reviewed-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-23-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Add prctl controls for userspace vector managementAndy Chiu3-1/+123
This patch add two riscv-specific prctls, to allow usespace control the use of vector unit: * PR_RISCV_V_SET_CONTROL: control the permission to use Vector at next, or all following execve for a thread. Turning off a thread's Vector live is not possible since libraries may have registered ifunc that may execute Vector instructions. * PR_RISCV_V_GET_CONTROL: get the same permission setting for the current thread, and the setting for following execve(s). Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Greentime Hu <greentime.hu@sifive.com> Reviewed-by: Vincent Chen <vincent.chen@sifive.com> Link: https://lore.kernel.org/r/20230605110724.21391-22-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: hwcap: change ELF_HWCAP to a functionAndy Chiu1-0/+5
Using a function is flexible to represent ELF_HWCAP. So the kernel may encode hwcap reflecting supported hardware features just at the moment of the start of each program. This will be helpful when we introduce prctl/sysctl interface to control per-process availability of Vector extension in following patches. Programs started with V disabled should see V masked off in theirs ELF_HWCAP. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230605110724.21391-21-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: prevent stack corruption by reserving task_pt_regs(p) earlyGreentime Hu1-0/+2
Early function calls, such as setup_vm(), relocate_enable_mmu(), soc_early_init() etc, are free to operate on stack. However, PT_SIZE_ON_STACK bytes at the head of the kernel stack are purposedly reserved for the placement of per-task register context pointed by task_pt_regs(p). Those functions may corrupt task_pt_regs if we overlap the $sp with it. In fact, we had accidentally corrupted sstatus.VS in some tests, treating the kernel to save V context before V was actually allocated, resulting in a kernel panic. Thus, we should skip PT_SIZE_ON_STACK for $sp before making C function calls from the top-level assembly. Co-developed-by: ShihPo Hung <shihpo.hung@sifive.com> Signed-off-by: ShihPo Hung <shihpo.hung@sifive.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-18-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: signal: validate altstack to reflect VectorAndy Chiu1-0/+7
Some extensions, such as Vector, dynamically change footprint on a signal frame, so MINSIGSTKSZ is no longer accurate. For example, an RV64V implementation with vlen = 512 may occupy 2K + 40 + 12 Bytes of a signal frame with the upcoming support. And processes that do not execute any vector instructions do not need to reserve the extra sigframe. So we need a way to guard the allocation size of the sigframe at process runtime according to current status of V. Thus, provide the function sigaltstack_size_valid() to validate its size based on current allocation status of supported extensions. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-17-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: signal: Report signal frame size to userspace via auxvVincent Chen1-5/+15
The vector register belongs to the signal context. They need to be stored and restored as entering and leaving the signal handler. According to the V-extension specification, the maximum length of the vector registers can be 2^16. Hence, if userspace refers to the MINSIGSTKSZ to create a sigframe, it may not be enough. To resolve this problem, this patch refers to the commit 94b07c1f8c39c ("arm64: signal: Report signal frame size to userspace via auxv") to enable userspace to know the minimum required sigframe size through the auxiliary vector and use it to allocate enough memory for signal context. Note that auxv always reports size of the sigframe as if V exists for all starting processes, whenever the kernel has CONFIG_RISCV_ISA_V. The reason is that users usually reference this value to allocate an alternative signal stack, and the user may use V anytime. So the user must reserve a space for V-context in sigframe in case that the signal handler invokes after the kernel allocating V. Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-16-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: signal: Add sigcontext save/restore for vectorGreentime Hu2-14/+163
This patch facilitates the existing fp-reserved words for placement of the first extension's context header on the user's sigframe. A context header consists of a distinct magic word and the size, including the header itself, of an extension on the stack. Then, the frame is followed by the context of that extension, and then a header + context body for another extension if exists. If there is no more extension to come, then the frame must be ended with a null context header. A special case is rv64gc, where the kernel support no extensions requiring to expose additional regfile to the user. In such case the kernel would place the null context header right after the first reserved word of __riscv_q_ext_state when saving sigframe. And the kernel would check if all reserved words are zeros when a signal handler returns. __riscv_q_ext_state---->| |<-__riscv_extra_ext_header ~ ~ .reserved[0]--->|0 |<- .reserved <-------|magic |<- .hdr | |size |_______ end of sc_fpregs | |ext-bdy| | ~ ~ +)size ------->|magic |<- another context header |size | |ext-bdy| ~ ~ |magic:0|<- null context header |size:0 | The vector registers will be saved in datap pointer. The datap pointer will be allocated dynamically when the task needs in kernel space. On the other hand, datap pointer on the sigframe will be set right after the __riscv_v_ext_state data structure. Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Suggested-by: Vineet Gupta <vineetg@rivosinc.com> Suggested-by: Richard Henderson <richard.henderson@linaro.org> Co-developed-by: Andy Chiu <andy.chiu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Acked-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-15-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: signal: check fp-reserved words unconditionallyAndy Chiu1-27/+28
In order to let kernel/user locate and identify an extension context on the existing sigframe, we are going to utilize reserved space of fp and encode the information there. And since the sigcontext has already preserved a space for fp context w or w/o CONFIG_FPU, we move those reserved words checking/setting routine back into generic code. This commit also undone an additional logical change carried by the refactor commit 007f5c3589578 ("Refactor FPU code in signal setup/return procedures"). Originally we did not restore fp context if restoring of gpr have failed. And it was fine on the other side. In such way the kernel could keep the regfiles intact, and potentially react at the failing point of restore. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Acked-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-14-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Add ptrace vector supportGreentime Hu1-0/+70
This patch adds ptrace support for riscv vector. The vector registers will be saved in datap pointer of __riscv_v_ext_state. This pointer will be set right after the __riscv_v_ext_state data structure then it will be put in ubuf for ptrace system call to get or set. It will check if the datap got from ubuf is set to the correct address or not when the ptrace system call is trying to set the vector registers. Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-13-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Allocate user's vector context in the first-use trapAndy Chiu2-2/+119
Vector unit is disabled by default for all user processes. Thus, a process will take a trap (illegal instruction) into kernel at the first time when it uses Vector. Only after then, the kernel allocates V context and starts take care of the context for that user process. Suggested-by: Richard Henderson <richard.henderson@linaro.org> Link: https://lore.kernel.org/r/3923eeee-e4dc-0911-40bf-84c34aee962d@linaro.org Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230605110724.21391-12-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Add task switch support for vectorGreentime Hu1-0/+19
This patch adds task switch support for vector. It also supports all lengths of vlen. Suggested-by: Andrew Waterman <andrew@sifive.com> Co-developed-by: Nick Knight <nick.knight@sifive.com> Signed-off-by: Nick Knight <nick.knight@sifive.com> Co-developed-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Co-developed-by: Ruinland Tsai <ruinland.tsai@sifive.com> Signed-off-by: Ruinland Tsai <ruinland.tsai@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Link: https://lore.kernel.org/r/20230605110724.21391-11-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Introduce riscv_v_vsize to record size of Vector contextGreentime Hu4-0/+46
This patch is used to detect the size of CPU vector registers and use riscv_v_vsize to save the size of all the vector registers. It assumes all harts has the same capabilities in a SMP system. If a core detects VLENB that is different from the boot core, then it warns and turns off V support for user space. Co-developed-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-9-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Disable Vector Instructions for kernel itselfGuo Ren2-9/+9
Disable vector instructions execution for kernel mode at its entrances. This helps find illegal uses of vector in the kernel space, which is similar to the fpu. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Co-developed-by: Vincent Chen <vincent.chen@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Co-developed-by: Han-Kuan Chen <hankuan.chen@sifive.com> Signed-off-by: Han-Kuan Chen <hankuan.chen@sifive.com> Co-developed-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-7-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Clear vector regfile on bootupGreentime Hu1-2/+25
clear vector registers on boot if kernel supports V. Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Signed-off-by: Vineet Gupta <vineetg@rivosinc.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Acked-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-6-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: hwprobe: Add support for probing V in RISCV_HWPROBE_KEY_IMA_EXT_0Andy Chiu1-0/+4
Probing kernel support for Vector extension is available now. This only add detection for V only. Extenions like Zvfh, Zk are not in this scope. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Evan Green <evan@rivosinc.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-4-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08riscv: Extending cpufeature.c to detect V-extensionGuo Ren1-0/+11
Add V-extension into riscv_isa_ext_keys array and detect it with isa string parsing. Signed-off-by: Guo Ren <ren_guo@c-sky.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Greentime Hu <greentime.hu@sifive.com> Suggested-by: Vineet Gupta <vineetg@rivosinc.com> Co-developed-by: Andy Chiu <andy.chiu@sifive.com> Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230605110724.21391-3-andy.chiu@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-07Merge patch series "riscv: allow case-insensitive ISA string parsing"Palmer Dabbelt2-19/+19
Yangyu Chen <cyy@cyyself.name> says: This patchset allows case-insensitive ISA string parsing, which is needed in the ACPI environment. As the RISC-V Hart Capabilities Table (RHCT) description in UEFI Forum ECR[1] shows the format of the ISA string is defined in the RISC-V unprivileged specification[2]. However, the RISC-V unprivileged specification defines the ISA naming strings are case-insensitive while the current ISA string parser in the kernel only accepts lowercase letters. In this case, the kernel should allow case-insensitive ISA string parsing. Moreover, this reason has been discussed in Conor's patch[3]. And I have also checked the current ISA string parsing in the recent ACPI support patch[4] will also call `riscv_fill_hwcap` function as DT we use now. The original motivation for my patch v1[5] is that some SoC generators will provide generated DT with illegal ISA string in dt-binding such as rocket-chip, which will even cause kernel panic in some cases as I mentioned in v1[5]. Now, the rocket-chip has been fixed in PR #3333[6]. However, when using some specific version of rocket-chip with illegal ISA string in DT, this patchset will also work for parsing uppercase letters correctly in DT, thus will have better compatibility. In summary, this patch not only works for case-insensitive ISA string parsing to meet the requirements in ECR[1] but also can be a workaround for some specific versions of rocket-chip. * b4-shazam-merge: dt-bindings: riscv: drop invalid comment about riscv,isa lower-case reasoning riscv: allow case-insensitive ISA string parsing Link: https://lore.kernel.org/r/tencent_E6911C8D71F5624E432A1AFDF86804C3B509@qq.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-07riscv: allow case-insensitive ISA string parsingYangyu Chen2-19/+19
According to RISC-V Hart Capabilities Table (RHCT) description in UEFI Forum ECR, the format of the ISA string is defined in the RISC-V unprivileged specification which is case-insensitive. However, the current ISA string parser in the kernel does not support ISA strings with uppercase letters. This patch modifies the ISA string parser in the kernel to support case-insensitive ISA string parsing. Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Yangyu Chen <cyy@cyyself.name> Link: https://lore.kernel.org/r/tencent_B30EED51C7235CA1988890E5C658BE35C107@qq.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-02Merge tag 'riscv-for-linus-6.4-rc5' of ↵Linus Torvalds1-0/+4
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: - A build warning fix for BUILTIN_DTB=y - Hibernation support is hidden behind NONPORTABLE, as it depends on some undocumented early boot behavior and breaks on most platforms - A fix for relocatable kernels on systems with early boot errata - A fix to properly handle perf callchains for kernel tracepoints - A pair of fixes for NAPOT to avoid inconsistencies between PTEs and handle hardware that sets arbitrary A/D bits * tag 'riscv-for-linus-6.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Implement missing huge_ptep_get riscv: Fix huge_ptep_set_wrprotect when PTE is a NAPOT riscv: perf: Fix callchain parse error with kernel tracepoint events riscv: Fix relocatable kernels with early alternatives using -fno-pie RISC-V: mark hibernation as nonportable riscv: Fix unused variable warning when BUILTIN_DTB is set
2023-06-01RISC-V: time.c: Add ACPI support for time_init()Sunil V L1-6/+19
On ACPI based platforms, timer related information is available in RHCT. Add ACPI based probe support to the timer initialization. Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230515054928.2079268-20-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01RISC-V: cpu: Enable cpuinfo for ACPI systemsSunil V L1-8/+22
On ACPI based platforms, few details like ISA need to be read from the ACPI table. Enable cpuinfo on ACPI based systems. ACPI has nothing similar to DT compatible property for each CPU. Hence, cpuinfo will not print "uarch". Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230515054928.2079268-16-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01RISC-V: cpufeature: Add ACPI support in riscv_fill_hwcap()Sunil V L1-10/+31
On ACPI based systems, the information about the hart like ISA is provided by the RISC-V Hart Capabilities Table (RHCT). Enable filling up hwcap structure based on the information in RHCT. Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230515054928.2079268-15-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01RISC-V: only iterate over possible CPUs in ISA string parserSunil V L1-5/+10
During boot we call riscv_of_processor_hartid() for each hart that we add to the possible cpus list. Repeating the call again here is not required, if we iterate over the list of possible CPUs, rather than the list of all CPUs. The call to of_property_read_string() for "riscv,isa" cannot fail either, as it has previously succeeded in riscv_of_processor_hartid(), but leaving in the error checking makes the operation of the loop more obvious & provides leeway for future refactoring of riscv_of_processor_hartid(). Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Co-developed-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20230515054928.2079268-14-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01RISC-V: smpboot: Add ACPI support in setup_smp()Sunil V L1-1/+71
Enable SMP boot on ACPI based platforms by using the RINTC structures in the MADT table. Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20230515054928.2079268-13-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01RISC-V: smpboot: Create wrapper setup_smp()Sunil V L1-1/+6
setup_smp() currently assumes DT-based platforms. To enable ACPI, first make this a wrapper function and move existing code to a separate DT-specific function. Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230515054928.2079268-12-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01RISC-V: ACPI: Cache and retrieve the RINTC structureSunil V L2-0/+49
RINTC structures in the MADT provide mapping between the hartid and the CPU. This is required many times even at run time like cpuinfo. So, instead of parsing the ACPI table every time, cache the RINTC structures and provide a function to get the correct RINTC structure for a given cpu. Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20230515054928.2079268-10-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>