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2023-06-01riscv: Implement missing huge_ptep_getAlexandre Ghiti
huge_ptep_get must be reimplemented in order to go through all the PTEs of a NAPOT region: this is needed because the HW can update the A/D bits of any of the PTE that constitutes the NAPOT region. Fixes: 82a1a1f3bfb6 ("riscv: mm: support Svnapot in hugetlb page") Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20230428120120.21620-2-alexghiti@rivosinc.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01riscv: perf: Fix callchain parse error with kernel tracepoint eventsIsm Hong
For RISC-V, when tracing with tracepoint events, the IP and status are set to 0, preventing the perf code parsing the callchain and resolving the symbols correctly. ./ply 'tracepoint:kmem/kmem_cache_alloc { @[stack]=count(); }' @: { <STACKID4294967282> }: 1 The fix is to implement perf_arch_fetch_caller_regs for riscv, which fills several necessary registers used for callchain unwinding, including epc, sp, s0 and status. It's similar to commit b3eac0265bf6 ("arm: perf: Fix callchain parse error with kernel tracepoint events") and commit 5b09a094f2fb ("arm64: perf: Fix callchain parse error with kernel tracepoint events"). With this patch, callchain can be parsed correctly as: ./ply 'tracepoint:kmem/kmem_cache_alloc { @[stack]=count(); }' @: { __traceiter_kmem_cache_alloc+68 __traceiter_kmem_cache_alloc+68 kmem_cache_alloc+354 __sigqueue_alloc+94 __send_signal_locked+646 send_signal_locked+154 do_send_sig_info+84 __kill_pgrp_info+130 kill_pgrp+60 isig+150 n_tty_receive_signal_char+36 n_tty_receive_buf_standard+2214 n_tty_receive_buf_common+280 n_tty_receive_buf2+26 tty_ldisc_receive_buf+34 tty_port_default_receive_buf+62 flush_to_ldisc+158 process_one_work+458 worker_thread+138 kthread+178 riscv_cpufeature_patch_func+832 }: 1 Signed-off-by: Ism Hong <ism.hong@gmail.com> Link: https://lore.kernel.org/r/20230601095355.1168910-1-ism.hong@gmail.com Fixes: 178e9fc47aae ("perf: riscv: preliminary RISC-V support") Cc: stable@vger.kernel.org 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>
2023-06-01drivers/acpi: RISC-V: Add RHCT related codeSunil V L
RHCT is a new table defined for RISC-V to communicate the features of the CPU to the OS. Create a new architecture folder in drivers/acpi and add RHCT parsing code. 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: Palmer Dabbelt <palmer@rivosinc.com> Link: https://lore.kernel.org/r/20230515054928.2079268-11-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>
2023-06-01ACPI: processor_core: RISC-V: Enable mapping processor to the hartidSunil V L
processor_core needs arch-specific functions to map the ACPI ID to the physical ID. In RISC-V platforms, hartid is the physical id and RINTC structure in MADT provides this mapping. Add arch-specific function to get this mapping from RINTC. 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/20230515054928.2079268-8-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>
2023-05-15riscv: 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
2023-05-05Merge tag 'locking-core-2023-05-05' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: - Introduce local{,64}_try_cmpxchg() - a slightly more optimal primitive, which will be used in perf events ring-buffer code - Simplify/modify rwsems on PREEMPT_RT, to address writer starvation - Misc cleanups/fixes * tag 'locking-core-2023-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/atomic: Correct (cmp)xchg() instrumentation locking/x86: Define arch_try_cmpxchg_local() locking/arch: Wire up local_try_cmpxchg() locking/generic: Wire up local{,64}_try_cmpxchg() locking/atomic: Add generic try_cmpxchg{,64}_local() support locking/rwbase: Mitigate indefinite writer starvation locking/arch: Rename all internal __xchg() names to __arch_xchg()
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
2023-04-29RISC-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>
2023-04-29RISC-V: Factor out common code of __cpu_resume_enter()Sia Jee Heng
The cpu_resume() function is very similar for the suspend to disk and suspend to ram cases. Factor out the common code into suspend_restore_csrs macro and suspend_restore_regs macro. Signed-off-by: Sia Jee Heng <jeeheng.sia@starfivetech.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230330064321.1008373-3-jeeheng.sia@starfivetech.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-29RISC-V: Change suspend_save_csrs and suspend_restore_csrs to public functionSia Jee Heng
Currently suspend_save_csrs() and suspend_restore_csrs() functions are statically defined in the suspend.c. Change the function's attribute to public so that the functions can be used by hibernation as well. 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/20230330064321.1008373-2-jeeheng.sia@starfivetech.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-29locking/arch: Rename all internal __xchg() names to __arch_xchg()Andrzej Hajda
Decrease the probability of this internal facility to be used by driver code. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Acked-by: Palmer Dabbelt <palmer@rivosinc.com> [riscv] Link: https://lore.kernel.org/r/20230118154450.73842-1-andrzej.hajda@intel.com Cc: Linus Torvalds <torvalds@linux-foundation.org>
2023-04-28Merge tag 'riscv-for-linus-6.4-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for runtime detection of the Svnapot extension - Support for Zicboz when clearing pages - We've moved to GENERIC_ENTRY - Support for !MMU on rv32 systems - The linear region is now mapped via huge pages - Support for building relocatable kernels - Support for the hwprobe interface - Various fixes and cleanups throughout the tree * tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (57 commits) RISC-V: hwprobe: Explicity check for -1 in vdso init RISC-V: hwprobe: There can only be one first riscv: Allow to downgrade paging mode from the command line dt-bindings: riscv: add sv57 mmu-type RISC-V: hwprobe: Remove __init on probe_vendor_features() riscv: Use --emit-relocs in order to move .rela.dyn in init riscv: Check relocations at compile time powerpc: Move script to check relocations at compile time in scripts/ riscv: Introduce CONFIG_RELOCATABLE riscv: Move .rela.dyn outside of init to avoid empty relocations riscv: Prepare EFI header for relocatable kernels riscv: Unconditionnally select KASAN_VMALLOC if KASAN riscv: Fix ptdump when KASAN is enabled riscv: Fix EFI stub usage of KASAN instrumented strcmp function riscv: Move DTB_EARLY_BASE_VA to the kernel address space riscv: Rework kasan population functions riscv: Split early and final KASAN population functions riscv: Use PUD/P4D/PGD pages for the linear mapping riscv: Move the linear mapping creation in its own function riscv: Get rid of riscv_pfn_base variable ...
2023-04-25RISC-V: hwprobe: Remove __init on probe_vendor_features()Evan Green
probe_vendor_features() is now called from smp_callin(), which is not __init code and runs during cpu hotplug events. Remove the __init_or_module decoration from it and the functions it calls to avoid walking into outer space. Fixes: 62a31d6e38bd ("RISC-V: hwprobe: Support probing of misaligned access performance") Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230420194934.1871356-1-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-25Merge tag 'irq-core-2023-04-24' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull interrupt updates from Thomas Gleixner: "Core: - Add tracepoints for tasklet callbacks which makes it possible to analyze individual tasklet functions instead of guess working from the overall duration of tasklet processing - Ensure that secondary interrupt threads have their affinity adjusted correctly Drivers: - A large rework of the RISC-V IPI management to prepare for a new RISC-V interrupt architecture - Small fixes and enhancements all over the place - Removal of support for various obsolete hardware platforms and the related code" * tag 'irq-core-2023-04-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits) irqchip/st: Remove stih415/stih416 and stid127 platforms support irqchip/gic-v3: Add Rockchip 3588001 erratum workaround genirq: Update affinity of secondary threads softirq: Add trace points for tasklet entry/exit irqchip/loongson-pch-pic: Fix pch_pic_acpi_init calling irqchip/loongson-pch-pic: Fix registration of syscore_ops irqchip/loongson-eiointc: Fix registration of syscore_ops irqchip/loongson-eiointc: Fix incorrect use of acpi_get_vec_parent irqchip/loongson-eiointc: Fix returned value on parsing MADT irqchip/riscv-intc: Add empty irq_eoi() for chained irq handlers RISC-V: Use IPIs for remote icache flush when possible RISC-V: Use IPIs for remote TLB flush when possible RISC-V: Allow marking IPIs as suitable for remote FENCEs RISC-V: Treat IPIs as normal Linux IRQs irqchip/riscv-intc: Allow drivers to directly discover INTC hwnode RISC-V: Clear SIP bit only when using SBI IPI operations irqchip/irq-sifive-plic: Add syscore callbacks for hibernation irqchip: Use of_property_read_bool() for boolean properties irqchip/bcm-6345-l1: Request memory region irqchip/gicv3: Workaround for NVIDIA erratum T241-FABRIC-4 ...
2023-04-21Merge tag 'irqchip-6.4' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core Pull irqchip changes from Marc Zyngier: - Large RISC-V IPI rework to make way for a new interrupt architecture - More Loongarch fixes from Lianmin Lv, fixing issues in the so called "dual-bridge" systems. - Workaround for the nvidia T241 chip that gets confused in 3 and 4 socket configurations, leading to the GIC malfunctionning in some contexts - Drop support for non-firmware driven GIC configurarations now that the old ARM11MP Cavium board is gone - Workaround for the Rockchip 3588 chip that doesn't correctly deal with the shareability attributes. - Replace uses of of_find_property() with the more appropriate of_property_read_bool() - Make bcm-6345-l1 request its MMIO region - Add suspend support to the SiFive PLIC - Drop support for stih415, stih416 and stid127 platforms Link: https://lore.kernel.org/lkml/20230421132104.3021536-1-maz@kernel.org
2023-04-21RISC-V: KVM: Virtualize per-HART AIA CSRsAnup Patel
The AIA specification introduce per-HART AIA CSRs which primarily support: * 64 local interrupts on both RV64 and RV32 * priority for each of the 64 local interrupts * interrupt filtering for local interrupts This patch virtualize above mentioned AIA CSRs and also extend ONE_REG interface to allow user-space save/restore Guest/VM view of these CSRs. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-21RISC-V: KVM: Use bitmap for irqs_pending and irqs_pending_maskAnup Patel
To support 64 VCPU local interrupts on RV32 host, we should use bitmap for irqs_pending and irqs_pending_mask in struct kvm_vcpu_arch. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-21RISC-V: KVM: Initial skeletal support for AIAAnup Patel
To incrementally implement AIA support, we first add minimal skeletal support which only compiles and detects AIA hardware support at the boot-time but does not provide any functionality. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-21RISC-V: KVM: Drop the _MASK suffix from hgatp.VMID mask definesAnup Patel
The hgatp.VMID mask defines are used before shifting when extracting VMID value from hgatp CSR value so based on the convention followed in the other parts of asm/csr.h, the hgatp.VMID mask defines should not have a _MASK suffix. While we are here, let's use GENMASK() for hgatp.VMID and hgatp.PPN. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-21RISC-V: Detect AIA CSRs from ISA stringAnup Patel
We have two extension names for AIA ISA support: Smaia (M-mode AIA CSRs) and Ssaia (S-mode AIA CSRs). We extend the ISA string parsing to detect Smaia and Ssaia extensions. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Signed-off-by: Anup Patel <anup@brainfault.org> Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-21RISC-V: Add AIA related CSR definesAnup Patel
The RISC-V AIA specification improves handling per-HART local interrupts in a backward compatible manner. This patch adds defines for new RISC-V AIA CSRs. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org> Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-21RISC-V: KVM: Add ONE_REG interface to enable/disable SBI extensionsAnup Patel
We add ONE_REG interface to enable/disable SBI extensions (just like the ONE_REG interface for ISA extensions). This allows KVM user-space to decide the set of SBI extension enabled for a Guest and by default all SBI extensions are enabled. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2023-04-19Merge patch series "Introduce 64b relocatable kernel"Palmer Dabbelt
Alexandre Ghiti <alexghiti@rivosinc.com> says: After multiple attempts, this patchset is now based on the fact that the 64b kernel mapping was moved outside the linear mapping. The first patch allows to build relocatable kernels but is not selected by default. That patch is a requirement for KASLR. The second and third patches take advantage of an already existing powerpc script that checks relocations at compile-time, and uses it for riscv. * b4-shazam-merge: riscv: Use --emit-relocs in order to move .rela.dyn in init riscv: Check relocations at compile time powerpc: Move script to check relocations at compile time in scripts/ riscv: Introduce CONFIG_RELOCATABLE riscv: Move .rela.dyn outside of init to avoid empty relocations riscv: Prepare EFI header for relocatable kernels Link: https://lore.kernel.org/r/20230329045329.64565-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-19riscv: Prepare EFI header for relocatable kernelsAlexandre Ghiti
ld does not handle relocations correctly as explained here [1], a fix for that was proposed by Nelson there but we have to support older toolchains and then provide this fix. Note that llvm does not need this fix and is then excluded. [1] https://sourceware.org/pipermail/binutils/2023-March/126690.html Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20230329045329.64565-2-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18Merge patch series "riscv: Use PUD/P4D/PGD pages for the linear mapping"Palmer Dabbelt
Alexandre Ghiti <alexghiti@rivosinc.com> says: This patchset intends to improve tlb utilization by using hugepages for the linear mapping. As reported by Anup in v6, when STRICT_KERNEL_RWX is enabled, we must take care of isolating the kernel text and rodata so that they are not mapped with a PUD mapping which would then assign wrong permissions to the whole region: it is achieved the same way as arm64 by using the memblock nomap API which isolates those regions and re-merge them afterwards thus avoiding any issue with the system resources tree creation. arch/riscv/include/asm/page.h | 19 ++++++- arch/riscv/mm/init.c | 102 ++++++++++++++++++++++++++-------- arch/riscv/mm/physaddr.c | 16 ++++++ drivers/of/fdt.c | 11 ++-- 4 files changed, 118 insertions(+), 30 deletions(-) * b4-shazam-merge: riscv: Use PUD/P4D/PGD pages for the linear mapping riscv: Move the linear mapping creation in its own function riscv: Get rid of riscv_pfn_base variable Link: https://lore.kernel.org/r/20230324155421.271544-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18riscv: Use PUD/P4D/PGD pages for the linear mappingAlexandre Ghiti
During the early page table creation, we used to set the mapping for PAGE_OFFSET to the kernel load address: but the kernel load address is always offseted by PMD_SIZE which makes it impossible to use PUD/P4D/PGD pages as this physical address is not aligned on PUD/P4D/PGD size (whereas PAGE_OFFSET is). But actually we don't have to establish this mapping (ie set va_pa_offset) that early in the boot process because: - first, setup_vm installs a temporary kernel mapping and among other things, discovers the system memory, - then, setup_vm_final creates the final kernel mapping and takes advantage of the discovered system memory to create the linear mapping. During the first phase, we don't know the start of the system memory and then until the second phase is finished, we can't use the linear mapping at all and phys_to_virt/virt_to_phys translations must not be used because it would result in a different translation from the 'real' one once the final mapping is installed. So here we simply delay the initialization of va_pa_offset to after the system memory discovery. But to make sure noone uses the linear mapping before, we add some guard in the DEBUG_VIRTUAL config. Finally we can use PUD/P4D/PGD hugepages when possible, which will result in a better TLB utilization. Note that: - this does not apply to rv32 as the kernel mapping lies in the linear mapping. - we rely on the firmware to protect itself using PMP. Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Acked-by: Rob Herring <robh@kernel.org> # DT bits Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org> Tested-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20230324155421.271544-4-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18riscv: Get rid of riscv_pfn_base variableAlexandre Ghiti
Use directly phys_ram_base instead, riscv_pfn_base is just the pfn of the address contained in phys_ram_base. Even if there is no functional change intended in this patch, actually setting phys_ram_base that early changes the behaviour of kernel_mapping_pa_to_va during the early boot: phys_ram_base used to be zero before this patch and now it is set to the physical start address of the kernel. But it does not break the conversion of a kernel physical address into a virtual address since kernel_mapping_pa_to_va should only be used on kernel physical addresses, i.e. addresses greater than the physical start address of the kernel. Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Anup Patel <anup@brainfault.org> Tested-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/r/20230324155421.271544-2-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18riscv: export cpu/freq invariant to schedulerSong Shuai
RISC-V now manages CPU topology using arch_topology which provides CPU capacity and frequency related interfaces to access the cpu/freq invariant in possible heterogeneous or DVFS-enabled platforms. Here adds topology.h file to export the arch_topology interfaces for replacing the scheduler's constant-based cpu/freq invariant accounting. Signed-off-by: Song Shuai <suagrfillet@gmail.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Ley Foon Tan <lftan@kernel.org> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230323123924.3032174-1-suagrfillet@gmail.com [Palmer: Fix the whitespace issues.] Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18Merge patch series "RISC-V Hardware Probing User Interface"Palmer Dabbelt
Evan Green <evan@rivosinc.com> says: There's been a bunch of off-list discussions about this, including at Plumbers. The original plan was to do something involving providing an ISA string to userspace, but ISA strings just aren't sufficient for a stable ABI any more: in order to parse an ISA string users need the version of the specifications that the string is written to, the version of each extension (sometimes at a finer granularity than the RISC-V releases/versions encode), and the expected use case for the ISA string (ie, is it a U-mode or M-mode string). That's a lot of complexity to try and keep ABI compatible and it's probably going to continue to grow, as even if there's no more complexity in the specifications we'll have to deal with the various ISA string parsing oddities that end up all over userspace. Instead this patch set takes a very different approach and provides a set of key/value pairs that encode various bits about the system. The big advantage here is that we can clearly define what these mean so we can ensure ABI stability, but it also allows us to encode information that's unlikely to ever appear in an ISA string (see the misaligned access performance, for example). The resulting interface looks a lot like what arm64 and x86 do, and will hopefully fit well into something like ACPI in the future. The actual user interface is a syscall, with a vDSO function in front of it. The vDSO function can answer some queries without a syscall at all, and falls back to the syscall for cases it doesn't have answers to. Currently we prepopulate it with an array of answers for all keys and a CPU set of "all CPUs". This can be adjusted as necessary to provide fast answers to the most common queries. An example series in glibc exposing this syscall and using it in an ifunc selector for memcpy can be found at [1]. I was asked about the performance delta between this and something like sysfs. I created a small test program and ran it on a Nezha D1 Allwinner board. Doing each operation 100000 times and dividing, these operations take the following amount of time: - open()+read()+close() of /sys/kernel/cpu_byteorder: 3.8us - access("/sys/kernel/cpu_byteorder", R_OK): 1.3us - riscv_hwprobe() vDSO and syscall: .0094us - riscv_hwprobe() vDSO with no syscall: 0.0091us These numbers get farther apart if we query multiple keys, as sysfs will scale linearly with the number of keys, where the dedicated syscall stays the same. To frame these numbers, I also did a tight fork/exec/wait loop, which I measured as 4.8ms. So doing 4 open/read/close operations is a delta of about 0.3%, versus a single vDSO call is a delta of essentially zero. [1] https://patchwork.ozlabs.org/project/glibc/list/?series=343050 * b4-shazam-merge: RISC-V: Add hwprobe vDSO function and data selftests: Test the new RISC-V hwprobe interface RISC-V: hwprobe: Support probing of misaligned access performance RISC-V: hwprobe: Add support for RISCV_HWPROBE_BASE_BEHAVIOR_IMA RISC-V: Add a syscall for HW probing RISC-V: Move struct riscv_cpuinfo to new header Link: https://lore.kernel.org/r/20230407231103.2622178-1-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18RISC-V: Add hwprobe vDSO function and dataEvan Green
Add a vDSO function __vdso_riscv_hwprobe, which can sit in front of the riscv_hwprobe syscall and answer common queries. We stash a copy of static answers for the "all CPUs" case in the vDSO data page. This data is private to the vDSO, so we can decide later to change what's stored there or under what conditions we defer to the syscall. Currently all data can be discovered at boot, so the vDSO function answers all queries when the cpumask is set to the "all CPUs" hint. There's also a boolean in the data that lets the vDSO function know that all CPUs are the same. In that case, the vDSO will also answer queries for arbitrary CPU masks in addition to the "all CPUs" hint. Signed-off-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20230407231103.2622178-7-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18RISC-V: hwprobe: Support probing of misaligned access performanceEvan Green
This allows userspace to select various routines to use based on the performance of misaligned access on the target hardware. Rather than adding DT bindings, this change taps into the alternatives mechanism used to probe CPU errata. Add a new function pointer alongside the vendor-specific errata_patch_func() that probes for desirable errata (otherwise known as "features"). Unlike the errata_patch_func(), this function is called on each CPU as it comes up, so it can save feature information per-CPU. The T-head C906 has fast unaligned access, both as defined by GCC [1], and in performing a basic benchmark, which determined that byte copies are >50% slower than a misaligned word copy of the same data size (source for this test at [2]): bytecopy size f000 count 50000 offset 0 took 31664899 us wordcopy size f000 count 50000 offset 0 took 5180919 us wordcopy size f000 count 50000 offset 1 took 13416949 us [1] https://github.com/gcc-mirror/gcc/blob/master/gcc/config/riscv/riscv.cc#L353 [2] https://pastebin.com/EPXvDHSW Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com> Link: https://lore.kernel.org/r/20230407231103.2622178-5-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18RISC-V: hwprobe: Add support for RISCV_HWPROBE_BASE_BEHAVIOR_IMAEvan Green
We have an implicit set of base behaviors that userspace depends on, which are mostly defined in various ISA specifications. Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Evan Green <evan@rivosinc.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: Paul Walmsley <paul.walmsley@sifive.com> Link: https://lore.kernel.org/r/20230407231103.2622178-4-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18RISC-V: Add a syscall for HW probingEvan Green
We don't have enough space for these all in ELF_HWCAP{,2} and there's no system call that quite does this, so let's just provide an arch-specific one to probe for hardware capabilities. This currently just provides m{arch,imp,vendor}id, but with the key-value pairs we can pass more in the future. Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Evan Green <evan@rivosinc.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: Paul Walmsley <paul.walmsley@sifive.com> Link: https://lore.kernel.org/r/20230407231103.2622178-3-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-18RISC-V: Move struct riscv_cpuinfo to new headerEvan Green
In preparation for tracking and exposing microarchitectural details to userspace (like whether or not unaligned accesses are fast), move the riscv_cpuinfo struct out to its own new cpufeatures.h header. It will need to be used by more than just cpu.c. Signed-off-by: Evan Green <evan@rivosinc.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: Paul Walmsley <paul.walmsley@sifive.com> Link: https://lore.kernel.org/r/20230407231103.2622178-2-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-13riscv: Move early dtb mapping into the fixmap regionAlexandre Ghiti
riscv establishes 2 virtual mappings: - early_pg_dir maps the kernel which allows to discover the system memory - swapper_pg_dir installs the final mapping (linear mapping included) We used to map the dtb in early_pg_dir using DTB_EARLY_BASE_VA, and this mapping was not carried over in swapper_pg_dir. It happens that early_init_fdt_scan_reserved_mem() must be called before swapper_pg_dir is setup otherwise we could allocate reserved memory defined in the dtb. And this function initializes reserved_mem variable with addresses that lie in the early_pg_dir dtb mapping: when those addresses are reused with swapper_pg_dir, this mapping does not exist and then we trap. The previous "fix" was incorrect as early_init_fdt_scan_reserved_mem() must be called before swapper_pg_dir is set up otherwise we could allocate in reserved memory defined in the dtb. So move the dtb mapping in the fixmap region which is established in early_pg_dir and handed over to swapper_pg_dir. Fixes: 922b0375fc93 ("riscv: Fix memblock reservation for device tree blob") Fixes: 8f3a2b4a96dc ("RISC-V: Move DT mapping outof fixmap") Fixes: 50e63dd8ed92 ("riscv: fix reserved memory setup") Reported-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/all/f8e67f82-103d-156c-deb0-d6d6e2756f5e@microchip.com/ Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Tested-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20230329081932.79831-2-alexghiti@rivosinc.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-08RISC-V: Allow marking IPIs as suitable for remote FENCEsAnup Patel
To do remote FENCEs (i.e. remote TLB flushes) using IPI calls on the RISC-V kernel, we need hardware mechanism to directly inject IPI from the supervisor mode (i.e. RISC-V kernel) instead of using SBI calls. The upcoming AIA IMSIC devices allow direct IPI injection from the supervisor mode (i.e. RISC-V kernel). To support this, we extend the riscv_ipi_set_virq_range() function so that IPI provider (i.e. irqchip drivers can mark IPIs as suitable for remote FENCEs. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230328035223.1480939-5-apatel@ventanamicro.com
2023-04-08RISC-V: Treat IPIs as normal Linux IRQsAnup Patel
Currently, the RISC-V kernel provides arch specific hooks (i.e. struct riscv_ipi_ops) to register IPI handling methods. The stats gathering of IPIs is also arch specific in the RISC-V kernel. Other architectures (such as ARM, ARM64, and MIPS) have moved away from custom arch specific IPI handling methods. Currently, these architectures have Linux irqchip drivers providing a range of Linux IRQ numbers to be used as IPIs and IPI triggering is done using generic IPI APIs. This approach allows architectures to treat IPIs as normal Linux IRQs and IPI stats gathering is done by the generic Linux IRQ subsystem. We extend the RISC-V IPI handling as-per above approach so that arch specific IPI handling methods (struct riscv_ipi_ops) can be removed and the IPI handling is done through the Linux IRQ subsystem. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230328035223.1480939-4-apatel@ventanamicro.com
2023-04-08irqchip/riscv-intc: Allow drivers to directly discover INTC hwnodeAnup Patel
Various RISC-V drivers (such as SBI IPI, SBI Timer, SBI PMU, and KVM RISC-V) don't have associated DT node but these drivers need standard per-CPU (local) interrupts defined by the RISC-V privileged specification. We add riscv_get_intc_hwnode() in arch/riscv which allows RISC-V drivers not having DT node to discover INTC hwnode which in-turn helps these drivers to map per-CPU (local) interrupts provided by the INTC driver. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230328035223.1480939-3-apatel@ventanamicro.com
2023-03-29Merge patch series "RISC-V: Fixes for riscv_has_extension[un]likely()'s ↵Palmer Dabbelt
alternative dependency" Conor Dooley <conor.dooley@microchip.com> says: Here's my attempt at fixing both the use of an FPU on XIP kernels and the issue that Jason ran into where CONFIG_FPU, which needs the alternatives frame work for has_fpu() checks, could be enabled without the alternatives actually being present. For the former, a "slow" fallback that does not use alternatives is added to riscv_has_extension_[un]likely() that can be used with XIP. Obviously, we want to make use of Jisheng's alternatives based approach where possible, so any users of riscv_has_extension_[un]likely() will want to make sure that they select RISCV_ALTERNATIVE. If they don't however, they'll hit the fallback path which (should, sparing a silly mistake from me!) behave in the same way, thus succeeding silently. Sounds like a To prevent "depends on !XIP_KERNEL; select RISCV_ALTERNATIVE" spreading like the plague through the various places that want to check for the presence of extensions, and sidestep the potential silent "success" mentioned above, all users RISCV_ALTERNATIVE are converted from selects to dependencies, with the option being selected for all !XIP_KERNEL builds. I know that the VDSO was a key place that Jisheng wanted to use the new helper rather than static branches, and I think the fallback path should not cause issues there. See the thread at [1] for the prior discussion. 1 - https://lore.kernel.org/linux-riscv/20230128172856.3814-1-jszhang@kernel.org/T/#m21390d570997145d31dd8bb95002fd61f99c6573 [Palmer: these were also merged into fixes, but there's a cleanup that depends on the merge so I'm taking it into for-next as well.] * b4-shazam-merge: RISC-V: always select RISCV_ALTERNATIVE for non-xip kernels RISC-V: add non-alternative fallback for riscv_has_extension_[un]likely() Link: https://lore.kernel.org/r/20230324100538.3514663-1-conor.dooley@microchip.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> * commit '1ee7fc3f4d0a93831a20d5566f203d5ad6d44de8': RISC-V: always select RISCV_ALTERNATIVE for non-xip kernels RISC-V: add non-alternative fallback for riscv_has_extension_[un]likely()
2023-03-29Merge patch series "RISC-V: Fixes for riscv_has_extension[un]likely()'s ↵Palmer Dabbelt
alternative dependency" Conor Dooley <conor.dooley@microchip.com> says: Here's my attempt at fixing both the use of an FPU on XIP kernels and the issue that Jason ran into where CONFIG_FPU, which needs the alternatives frame work for has_fpu() checks, could be enabled without the alternatives actually being present. For the former, a "slow" fallback that does not use alternatives is added to riscv_has_extension_[un]likely() that can be used with XIP. Obviously, we want to make use of Jisheng's alternatives based approach where possible, so any users of riscv_has_extension_[un]likely() will want to make sure that they select RISCV_ALTERNATIVE. If they don't however, they'll hit the fallback path which (should, sparing a silly mistake from me!) behave in the same way, thus succeeding silently. Sounds like a To prevent "depends on !XIP_KERNEL; select RISCV_ALTERNATIVE" spreading like the plague through the various places that want to check for the presence of extensions, and sidestep the potential silent "success" mentioned above, all users RISCV_ALTERNATIVE are converted from selects to dependencies, with the option being selected for all !XIP_KERNEL builds. I know that the VDSO was a key place that Jisheng wanted to use the new helper rather than static branches, and I think the fallback path should not cause issues there. See the thread at [1] for the prior discussion. 1 - https://lore.kernel.org/linux-riscv/20230128172856.3814-1-jszhang@kernel.org/T/#m21390d570997145d31dd8bb95002fd61f99c6573 [Palmer: merging in the fixes as a branch as there's some features that depend on it.] * b4-shazam-merge: RISC-V: always select RISCV_ALTERNATIVE for non-xip kernels RISC-V: add non-alternative fallback for riscv_has_extension_[un]likely() Link: https://lore.kernel.org/r/20230324100538.3514663-1-conor.dooley@microchip.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-03-29RISC-V: add non-alternative fallback for riscv_has_extension_[un]likely()Conor Dooley
The has_fpu() check, which in turn calls riscv_has_extension_likely(), relies on alternatives to figure out whether the system has an FPU. As a result, it will malfunction on XIP kernels, as they do not support the alternatives mechanism. When alternatives support is not present, fall back to using __riscv_isa_extension_available() in riscv_has_extension_[un]likely() instead stead, which handily takes the same argument, so that kernels that do not support alternatives can accurately report the presence of FPU support. Fixes: 702e64550b12 ("riscv: fpu: switch has_fpu() to riscv_has_extension_likely()") Link: https://lore.kernel.org/all/ad445951-3d13-4644-94d9-e0989cda39c3@spud/ Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com> Link: https://lore.kernel.org/r/20230324100538.3514663-2-conor.dooley@microchip.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-03-24Merge patch series "riscv: Add GENERIC_ENTRY support"Palmer Dabbelt
guoren@kernel.org <guoren@kernel.org> says: From: Guo Ren <guoren@linux.alibaba.com> The patches convert riscv to use the generic entry infrastructure from kernel/entry/*. Some optimization for entry.S with new .macro and merge ret_from_kernel_thread into ret_from_fork. * b4-shazam-merge: riscv: entry: Consolidate general regs saving/restoring riscv: entry: Consolidate ret_from_kernel_thread into ret_from_fork riscv: entry: Remove extra level wrappers of trace_hardirqs_{on,off} riscv: entry: Convert to generic entry riscv: entry: Add noinstr to prevent instrumentation inserted riscv: ptrace: Remove duplicate operation Link: https://lore.kernel.org/r/20230222033021.983168-1-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-03-23riscv: entry: Consolidate general regs saving/restoringJisheng Zhang
Consolidate the saving/restoring GPs (except zero, ra, sp, gp, tp and t0) into save_from_x6_to_x31/restore_from_x6_to_x31 macros. No functional change intended. Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Guo Ren <guoren@kernel.org> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Tested-by: Guo Ren <guoren@kernel.org> Signed-off-by: Guo Ren <guoren@kernel.org> Link: https://lore.kernel.org/r/20230222033021.983168-8-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-03-23riscv: entry: Convert to generic entryGuo Ren
This patch converts riscv to use the generic entry infrastructure from kernel/entry/*. The generic entry makes maintainers' work easier and codes more elegant. Here are the changes: - More clear entry.S with handle_exception and ret_from_exception - Get rid of complex custom signal implementation - Move syscall procedure from assembly to C, which is much more readable. - Connect ret_from_fork & ret_from_kernel_thread to generic entry. - Wrap with irqentry_enter/exit and syscall_enter/exit_from_user_mode - Use the standard preemption code instead of custom Suggested-by: Huacai Chen <chenhuacai@kernel.org> Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Tested-by: Yipeng Zou <zouyipeng@huawei.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> Cc: Ben Hutchings <ben@decadent.org.uk> Link: https://lore.kernel.org/r/20230222033021.983168-5-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>