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2023-06-19RISC-V: hwprobe: Expose Zba, Zbb, and ZbsEvan Green
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 Green
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 Green
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 L
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 Shuai
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 Shuai
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 Dooks
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 Dabbelt
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 Chiu
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 Chiu
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 Chiu
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 Hu
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 Chiu
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 Chen
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 Hu
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 Chiu
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 Hu
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 Chiu
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 Hu
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 Hu
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 Ren
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 Hu
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 Chiu
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 Ren
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>
2023-06-06Merge patch series "riscv: allow case-insensitive ISA string parsing"Palmer Dabbelt
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>
2023-06-06riscv: allow case-insensitive ISA string parsingYangyu Chen
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 Torvalds
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 L
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 L
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 L
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 L
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 L
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 L
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 L
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>
2023-06-01RISC-V: Add ACPI initialization in setup_arch()Sunil V L
Initialize the ACPI core for RISC-V during boot. ACPI tables and interpreter are initialized based on the information passed from the firmware and the value of the kernel parameter 'acpi'. With ACPI support added for RISC-V, the kernel parameter 'acpi' is also supported on RISC-V. Hence, update the documentation. 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> Acked-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230515054928.2079268-9-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01RISC-V: Add support to build the ACPI coreSunil V L
Enable ACPI core for RISC-V after adding architecture-specific interfaces and header files required to build the ACPI core. 1) Couple of header files are required unconditionally by the ACPI core. Add empty acenv.h and cpu.h header files. 2) If CONFIG_PCI is enabled, a few PCI related interfaces need to be provided by the architecture. Define dummy interfaces for now so that build succeeds. Actual implementation will be added when PCI support is added for ACPI along with external interrupt controller support. 3) A few globals and memory mapping related functions specific to the architecture need to be provided. 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> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230515054928.2079268-7-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01riscv: move sbi_init() earlier before jump_label_init()Jisheng Zhang
We call jump_label_init() in setup_arch() is to use static key mechanism earlier, but riscv jump label relies on the sbi functions, If we enable static key before sbi_init(), the code path looks like: static_branch_enable() .. arch_jump_label_transform() patch_text_nosync() flush_icache_range() flush_icache_all() sbi_remote_fence_i() for CONFIG_RISCV_SBI case __sbi_rfence() Since sbi isn't initialized, so NULL deference! Here is a typical panic log: [ 0.000000] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 0.000000] Oops [#1] [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0-rc7+ #79 [ 0.000000] Hardware name: riscv-virtio,qemu (DT) [ 0.000000] epc : 0x0 [ 0.000000] ra : sbi_remote_fence_i+0x1e/0x26 [ 0.000000] epc : 0000000000000000 ra : ffffffff80005826 sp : ffffffff80c03d50 [ 0.000000] gp : ffffffff80ca6178 tp : ffffffff80c0ad80 t0 : 6200000000000000 [ 0.000000] t1 : 0000000000000000 t2 : 62203a6b746e6972 s0 : ffffffff80c03d60 [ 0.000000] s1 : ffffffff80001af6 a0 : 0000000000000000 a1 : 0000000000000000 [ 0.000000] a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000 [ 0.000000] a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000000080200 [ 0.000000] s2 : ffffffff808b3e48 s3 : ffffffff808bf698 s4 : ffffffff80cb2818 [ 0.000000] s5 : 0000000000000001 s6 : ffffffff80c9c345 s7 : ffffffff80895aa0 [ 0.000000] s8 : 0000000000000001 s9 : 000000000000007f s10: 0000000000000000 [ 0.000000] s11: 0000000000000000 t3 : ffffffff80824d08 t4 : 0000000000000022 [ 0.000000] t5 : 000000000000003d t6 : 0000000000000000 [ 0.000000] status: 0000000000000100 badaddr: 0000000000000000 cause: 000000000000000c [ 0.000000] ---[ end trace 0000000000000000 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- Fix this issue by moving sbi_init() earlier before jump_label_init() Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Atish Patra <atishp@rivosinc.com> Link: https://lore.kernel.org/r/20230515054928.2079268-2-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-05-31riscv: Fix relocatable kernels with early alternatives using -fno-pieAlexandre Ghiti
Early alternatives are called with the mmu disabled, and then should not access any global symbols through the GOT since it requires relocations, relocations that we do before but *virtually*. So only use medany code model for this early code. Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Tested-by: Conor Dooley <conor.dooley@microchip.com> # booted on nezha & unmatched Fixes: 39b33072941f ("riscv: Introduce CONFIG_RELOCATABLE") Link: https://lore.kernel.org/r/20230526154630.289374-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-05-18Merge tag 'probes-fixes-v6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull probes fixes from Masami Hiramatsu: - Initialize 'ret' local variables on fprobe_handler() to fix the smatch warning. With this, fprobe function exit handler is not working randomly. - Fix to use preempt_enable/disable_notrace for rethook handler to prevent recursive call of fprobe exit handler (which is based on rethook) - Fix recursive call issue on fprobe_kprobe_handler() - Fix to detect recursive call on fprobe_exit_handler() - Fix to make all arch-dependent rethook code notrace (the arch-independent code is already notrace)" * tag 'probes-fixes-v6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: rethook, fprobe: do not trace rethook related functions fprobe: add recursion detection in fprobe_exit_handler fprobe: make fprobe_kprobe_handler recursion free rethook: use preempt_{disable, enable}_notrace in rethook_trampoline_handler tracing: fprobe: Initialize ret valiable to fix smatch error
2023-05-18rethook, fprobe: do not trace rethook related functionsZe Gao
These functions are already marked as NOKPROBE to prevent recursion and we have the same reason to blacklist them if rethook is used with fprobe, since they are beyond the recursion-free region ftrace can guard. Link: https://lore.kernel.org/all/20230517034510.15639-5-zegao@tencent.com/ Fixes: f3a112c0c40d ("x86,rethook,kprobes: Replace kretprobe with rethook on x86") Signed-off-by: Ze Gao <zegao@tencent.com> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-05-15riscv: Switch to hotplug core state synchronizationThomas Gleixner
Switch to the CPU hotplug core state tracking and synchronization mechanim. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Tested-by: Michael Kelley <mikelley@microsoft.com> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name> Tested-by: Helge Deller <deller@gmx.de> # parisc Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck Link: https://lore.kernel.org/r/20230512205256.916055844@linutronix.de
2023-05-09riscv: Fix orphan section warnings caused by kernel/piAlexandre Ghiti
kernel/pi gives rise to a lot of new sections that end up orphans: the first attempt to fix that tried to enumerate them all in the linker script, but kernel test robot with a random config keeps finding more of them. So prefix all those sections with .init.pi instead of only .init in order to be able to easily catch them all in the linker script. Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/oe-kbuild-all/202304301606.Cgp113Ha-lkp@intel.com/ Fixes: 26e7aacb83df ("riscv: Allow to downgrade paging mode from the command line") Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20230504120759.18730-1-alexghiti@rivosinc.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-05-05Merge tag 'riscv-for-linus-6.4-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 hibernation - The .rela.dyn section has been moved to the init area - A fix for the SBI probing to allow for implementation-defined behavior - Various other fixes and cleanups throughout the tree * tag 'riscv-for-linus-6.4-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: RISC-V: include cpufeature.h in cpufeature.c riscv: Move .rela.dyn to the init sections dt-bindings: riscv: explicitly mention assumption of Zicsr & Zifencei support riscv: compat_syscall_table: Fixup compile warning RISC-V: fixup in-flight collision with ARCH_WANT_OPTIMIZE_VMEMMAP rename RISC-V: fix sifive and thead section mismatches in errata RISC-V: Align SBI probe implementation with spec riscv: mm: remove redundant parameter of create_fdt_early_page_table riscv: Adjust dependencies of HAVE_DYNAMIC_FTRACE selection RISC-V: Add arch functions to support hibernation/suspend-to-disk RISC-V: mm: Enable huge page support to kernel_page_present() function RISC-V: Factor out common code of __cpu_resume_enter() RISC-V: Change suspend_save_csrs and suspend_restore_csrs to public function
2023-05-05Merge tag 'kvm-riscv-6.4-1' of https://github.com/kvm-riscv/linux into HEADPaolo Bonzini
KVM/riscv changes for 6.4 - ONE_REG interface to enable/disable SBI extensions - Zbb extension for Guest/VM - AIA CSR virtualization
2023-05-01RISC-V: include cpufeature.h in cpufeature.cConor Dooley
Automation complains: warning: symbol '__pcpu_scope_misaligned_access_speed' was not declared. Should it be static? cpufeature.c doesn't actually include the header of the same name, as it had not previously used anything from it. The per-cpu variable is declared there, so include it to silence the complaints. Fixes: 62a31d6e38bd ("RISC-V: hwprobe: Support probing of misaligned access performance") Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20230420-wound-gizzard-2b2b589d9bea@spud Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-05-01riscv: Move .rela.dyn to the init sectionsAlexandre Ghiti
The recent introduction of relocatable kernels prepared the move of .rela.dyn to the init section, but actually forgot to do so, so do it here. Before this patch: "Freeing unused kernel image (initmem) memory: 2592K" After this patch: "Freeing unused kernel image (initmem) memory: 6288K" The difference corresponds to the size of the .rela.dyn section: "[42] .rela.dyn RELA ffffffff8197e798 0127f798 000000000039c660 0000000000000018 A 47 0 8" Fixes: 559d1e45a16d ("riscv: Use --emit-relocs in order to move .rela.dyn in init") Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20230428120932.22735-1-alexghiti@rivosinc.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-05-01riscv: compat_syscall_table: Fixup compile warningGuo Ren
../arch/riscv/kernel/compat_syscall_table.c:12:41: warning: initialized field overwritten [-Woverride-init] 12 | #define __SYSCALL(nr, call) [nr] = (call), | ^ ../include/uapi/asm-generic/unistd.h:567:1: note: in expansion of macro '__SYSCALL' 567 | __SYSCALL(__NR_semget, sys_semget) Fixes: 59c10c52f573 ("riscv: compat: syscall: Add compat_sys_call_table implementation") Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reported-by: kernel test robot <lkp@intel.com> Tested-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Signed-off-by: Drew Fustini <dfustini@baylibre.com> Link: https://lore.kernel.org/r/20230501223353.2833899-1-dfustini@baylibre.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-29RISC-V: Align SBI probe implementation with specAndrew Jones
sbi_probe_extension() is specified with "Returns 0 if the given SBI extension ID (EID) is not available, or 1 if it is available unless defined as any other non-zero value by the implementation." Additionally, sbiret.value is a long. Fix the implementation to ensure any nonzero long value is considered a success, rather than only positive int values. Fixes: b9dcd9e41587 ("RISC-V: Add basic support for SBI v0.2") Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230427163626.101042-1-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-29Merge patch series "RISC-V Hibernation Support"Palmer Dabbelt
Sia Jee Heng <jeeheng.sia@starfivetech.com> says: This series adds RISC-V Hibernation/suspend to disk support. Low level Arch functions were created to support hibernation. swsusp_arch_suspend() relies code from __cpu_suspend_enter() to write cpu state onto the stack, then calling swsusp_save() to save the memory image. Arch specific hibernation header is implemented and is utilized by the arch_hibernation_header_restore() and arch_hibernation_header_save() functions. The arch specific hibernation header consists of satp, hartid, and the cpu_resume address. The kernel built version is also need to be saved into the hibernation image header to making sure only the same kernel is restore when resume. swsusp_arch_resume() creates a temporary page table that covering only the linear map. It copies the restore code to a 'safe' page, then start to restore the memory image. Once completed, it restores the original kernel's page table. It then calls into __hibernate_cpu_resume() to restore the CPU context. Finally, it follows the normal hibernation path back to the hibernation core. To enable hibernation/suspend to disk into RISCV, the below config need to be enabled: - CONFIG_HIBERNATION - CONFIG_ARCH_HIBERNATION_HEADER - CONFIG_ARCH_HIBERNATION_POSSIBLE At high-level, this series includes the following changes: 1) Change suspend_save_csrs() and suspend_restore_csrs() to public function as these functions are common to suspend/hibernation. (patch 1) 2) Refactor the common code in the __cpu_resume_enter() function and __hibernate_cpu_resume() function. The common code are used by hibernation and suspend. (patch 2) 3) Enhance kernel_page_present() function to support huge page. (patch 3) 4) Add arch/riscv low level functions to support hibernation/suspend to disk. (patch 4) * b4-shazam-merge: RISC-V: Add arch functions to support hibernation/suspend-to-disk RISC-V: mm: Enable huge page support to kernel_page_present() function RISC-V: Factor out common code of __cpu_resume_enter() RISC-V: Change suspend_save_csrs and suspend_restore_csrs to public function Link: https://lore.kernel.org/r/20230330064321.1008373-1-jeeheng.sia@starfivetech.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-29RISC-V: Add arch functions to support hibernation/suspend-to-diskSia Jee Heng
Low level Arch functions were created to support hibernation. swsusp_arch_suspend() relies code from __cpu_suspend_enter() to write cpu state onto the stack, then calling swsusp_save() to save the memory image. Arch specific hibernation header is implemented and is utilized by the arch_hibernation_header_restore() and arch_hibernation_header_save() functions. The arch specific hibernation header consists of satp, hartid, and the cpu_resume address. The kernel built version is also need to be saved into the hibernation image header to making sure only the same kernel is restore when resume. swsusp_arch_resume() creates a temporary page table that covering only the linear map. It copies the restore code to a 'safe' page, then start to restore the memory image. Once completed, it restores the original kernel's page table. It then calls into __hibernate_cpu_resume() to restore the CPU context. Finally, it follows the normal hibernation path back to the hibernation core. To enable hibernation/suspend to disk into RISCV, the below config need to be enabled: - CONFIG_HIBERNATION - CONFIG_ARCH_HIBERNATION_HEADER - CONFIG_ARCH_HIBERNATION_POSSIBLE Signed-off-by: Sia Jee Heng <jeeheng.sia@starfivetech.com> Reviewed-by: Ley Foon Tan <leyfoon.tan@starfivetech.com> Reviewed-by: Mason Huo <mason.huo@starfivetech.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20230330064321.1008373-5-jeeheng.sia@starfivetech.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>