diff options
Diffstat (limited to 'arch/riscv/kernel')
| -rw-r--r-- | arch/riscv/kernel/Makefile | 2 | ||||
| -rw-r--r-- | arch/riscv/kernel/asm-offsets.c | 3 | ||||
| -rw-r--r-- | arch/riscv/kernel/cpu.c | 6 | ||||
| -rw-r--r-- | arch/riscv/kernel/cpu_ops_sbi.c | 2 | ||||
| -rw-r--r-- | arch/riscv/kernel/head.S | 27 | ||||
| -rw-r--r-- | arch/riscv/kernel/module.c | 4 | ||||
| -rw-r--r-- | arch/riscv/kernel/perf_callchain.c | 2 | ||||
| -rw-r--r-- | arch/riscv/kernel/process.c | 3 | ||||
| -rw-r--r-- | arch/riscv/kernel/stacktrace.c | 6 | ||||
| -rw-r--r-- | arch/riscv/kernel/suspend.c | 87 | ||||
| -rw-r--r-- | arch/riscv/kernel/suspend_entry.S | 124 |
11 files changed, 231 insertions, 35 deletions
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index e0133d113216..87adbe47bc15 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -48,6 +48,8 @@ obj-$(CONFIG_RISCV_BOOT_SPINWAIT) += cpu_ops_spinwait.o obj-$(CONFIG_MODULES) += module.o obj-$(CONFIG_MODULE_SECTIONS) += module-sections.o +obj-$(CONFIG_CPU_PM) += suspend_entry.o suspend.o + obj-$(CONFIG_FUNCTION_TRACER) += mcount.o ftrace.o obj-$(CONFIG_DYNAMIC_FTRACE) += mcount-dyn.o diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c index df0519a64eaf..df9444397908 100644 --- a/arch/riscv/kernel/asm-offsets.c +++ b/arch/riscv/kernel/asm-offsets.c @@ -13,6 +13,7 @@ #include <asm/thread_info.h> #include <asm/ptrace.h> #include <asm/cpu_ops_sbi.h> +#include <asm/suspend.h> void asm_offsets(void); @@ -113,6 +114,8 @@ void asm_offsets(void) OFFSET(PT_BADADDR, pt_regs, badaddr); OFFSET(PT_CAUSE, pt_regs, cause); + OFFSET(SUSPEND_CONTEXT_REGS, suspend_context, regs); + OFFSET(KVM_ARCH_GUEST_ZERO, kvm_vcpu_arch, guest_context.zero); OFFSET(KVM_ARCH_GUEST_RA, kvm_vcpu_arch, guest_context.ra); OFFSET(KVM_ARCH_GUEST_SP, kvm_vcpu_arch, guest_context.sp); diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c index d2a936195295..ccb617791e56 100644 --- a/arch/riscv/kernel/cpu.c +++ b/arch/riscv/kernel/cpu.c @@ -69,11 +69,11 @@ int riscv_of_parent_hartid(struct device_node *node) .uprop = #UPROP, \ .isa_ext_id = EXTID, \ } -/** +/* * Here are the ordering rules of extension naming defined by RISC-V * specification : * 1. All extensions should be separated from other multi-letter extensions - * from other multi-letter extensions by an underscore. + * by an underscore. * 2. The first letter following the 'Z' conventionally indicates the most * closely related alphabetical extension category, IMAFDQLCBKJTPVH. * If multiple 'Z' extensions are named, they should be ordered first @@ -110,7 +110,7 @@ static void print_isa_ext(struct seq_file *f) } } -/** +/* * These are the only valid base (single letter) ISA extensions as per the spec. * It also specifies the canonical order in which it appears in the spec. * Some of the extension may just be a place holder for now (B, K, P, J). diff --git a/arch/riscv/kernel/cpu_ops_sbi.c b/arch/riscv/kernel/cpu_ops_sbi.c index 2e16f6732cdf..4f5a6f84e2a4 100644 --- a/arch/riscv/kernel/cpu_ops_sbi.c +++ b/arch/riscv/kernel/cpu_ops_sbi.c @@ -21,7 +21,7 @@ const struct cpu_operations cpu_ops_sbi; * be invoked from multiple threads in parallel. Define a per cpu data * to handle that. */ -DEFINE_PER_CPU(struct sbi_hart_boot_data, boot_data); +static DEFINE_PER_CPU(struct sbi_hart_boot_data, boot_data); static int sbi_hsm_hart_start(unsigned long hartid, unsigned long saddr, unsigned long priv) diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index ec07f991866a..893b8bb69391 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -16,26 +16,6 @@ #include <asm/image.h> #include "efi-header.S" -#ifdef CONFIG_XIP_KERNEL -.macro XIP_FIXUP_OFFSET reg - REG_L t0, _xip_fixup - add \reg, \reg, t0 -.endm -.macro XIP_FIXUP_FLASH_OFFSET reg - la t0, __data_loc - REG_L t1, _xip_phys_offset - sub \reg, \reg, t1 - add \reg, \reg, t0 -.endm -_xip_fixup: .dword CONFIG_PHYS_RAM_BASE - CONFIG_XIP_PHYS_ADDR - XIP_OFFSET -_xip_phys_offset: .dword CONFIG_XIP_PHYS_ADDR + XIP_OFFSET -#else -.macro XIP_FIXUP_OFFSET reg -.endm -.macro XIP_FIXUP_FLASH_OFFSET reg -.endm -#endif /* CONFIG_XIP_KERNEL */ - __HEAD ENTRY(_start) /* @@ -89,7 +69,8 @@ pe_head_start: .align 2 #ifdef CONFIG_MMU -relocate: + .global relocate_enable_mmu +relocate_enable_mmu: /* Relocate return address */ la a1, kernel_map XIP_FIXUP_OFFSET a1 @@ -184,7 +165,7 @@ secondary_start_sbi: /* Enable virtual memory and relocate to virtual address */ la a0, swapper_pg_dir XIP_FIXUP_OFFSET a0 - call relocate + call relocate_enable_mmu #endif call setup_trap_vector tail smp_callin @@ -328,7 +309,7 @@ clear_bss_done: #ifdef CONFIG_MMU la a0, early_pg_dir XIP_FIXUP_OFFSET a0 - call relocate + call relocate_enable_mmu #endif /* CONFIG_MMU */ call setup_trap_vector diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c index 4a48287513c3..c29cef90d1dd 100644 --- a/arch/riscv/kernel/module.c +++ b/arch/riscv/kernel/module.c @@ -69,7 +69,7 @@ static int apply_r_riscv_jal_rela(struct module *me, u32 *location, return 0; } -static int apply_r_riscv_rcv_branch_rela(struct module *me, u32 *location, +static int apply_r_riscv_rvc_branch_rela(struct module *me, u32 *location, Elf_Addr v) { ptrdiff_t offset = (void *)v - (void *)location; @@ -301,7 +301,7 @@ static int (*reloc_handlers_rela[]) (struct module *me, u32 *location, [R_RISCV_64] = apply_r_riscv_64_rela, [R_RISCV_BRANCH] = apply_r_riscv_branch_rela, [R_RISCV_JAL] = apply_r_riscv_jal_rela, - [R_RISCV_RVC_BRANCH] = apply_r_riscv_rcv_branch_rela, + [R_RISCV_RVC_BRANCH] = apply_r_riscv_rvc_branch_rela, [R_RISCV_RVC_JUMP] = apply_r_riscv_rvc_jump_rela, [R_RISCV_PCREL_HI20] = apply_r_riscv_pcrel_hi20_rela, [R_RISCV_PCREL_LO12_I] = apply_r_riscv_pcrel_lo12_i_rela, diff --git a/arch/riscv/kernel/perf_callchain.c b/arch/riscv/kernel/perf_callchain.c index 55faa4991b87..3348a61de7d9 100644 --- a/arch/riscv/kernel/perf_callchain.c +++ b/arch/riscv/kernel/perf_callchain.c @@ -68,7 +68,7 @@ void perf_callchain_user(struct perf_callchain_entry_ctx *entry, static bool fill_callchain(void *entry, unsigned long pc) { - return perf_callchain_store(entry, pc); + return perf_callchain_store(entry, pc) == 0; } void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index 03ac3aa611f5..504b496787aa 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -23,6 +23,7 @@ #include <asm/string.h> #include <asm/switch_to.h> #include <asm/thread_info.h> +#include <asm/cpuidle.h> register unsigned long gp_in_global __asm__("gp"); @@ -37,7 +38,7 @@ extern asmlinkage void ret_from_kernel_thread(void); void arch_cpu_idle(void) { - wait_for_interrupt(); + cpu_do_idle(); raw_local_irq_enable(); } diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c index 14d2b53ec322..08d11a53f39e 100644 --- a/arch/riscv/kernel/stacktrace.c +++ b/arch/riscv/kernel/stacktrace.c @@ -14,8 +14,6 @@ #include <asm/stacktrace.h> -register unsigned long sp_in_global __asm__("sp"); - #ifdef CONFIG_FRAME_POINTER void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs, @@ -30,7 +28,7 @@ void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs, pc = instruction_pointer(regs); } else if (task == NULL || task == current) { fp = (unsigned long)__builtin_frame_address(0); - sp = sp_in_global; + sp = current_stack_pointer; pc = (unsigned long)walk_stackframe; } else { /* task blocked in __switch_to */ @@ -78,7 +76,7 @@ void notrace walk_stackframe(struct task_struct *task, sp = user_stack_pointer(regs); pc = instruction_pointer(regs); } else if (task == NULL || task == current) { - sp = sp_in_global; + sp = current_stack_pointer; pc = (unsigned long)walk_stackframe; } else { /* task blocked in __switch_to */ diff --git a/arch/riscv/kernel/suspend.c b/arch/riscv/kernel/suspend.c new file mode 100644 index 000000000000..9ba24fb8cc93 --- /dev/null +++ b/arch/riscv/kernel/suspend.c @@ -0,0 +1,87 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * Copyright (c) 2022 Ventana Micro Systems Inc. + */ + +#include <linux/ftrace.h> +#include <asm/csr.h> +#include <asm/suspend.h> + +static void suspend_save_csrs(struct suspend_context *context) +{ + context->scratch = csr_read(CSR_SCRATCH); + context->tvec = csr_read(CSR_TVEC); + context->ie = csr_read(CSR_IE); + + /* + * No need to save/restore IP CSR (i.e. MIP or SIP) because: + * + * 1. For no-MMU (M-mode) kernel, the bits in MIP are set by + * external devices (such as interrupt controller, timer, etc). + * 2. For MMU (S-mode) kernel, the bits in SIP are set by + * M-mode firmware and external devices (such as interrupt + * controller, etc). + */ + +#ifdef CONFIG_MMU + context->satp = csr_read(CSR_SATP); +#endif +} + +static void suspend_restore_csrs(struct suspend_context *context) +{ + csr_write(CSR_SCRATCH, context->scratch); + csr_write(CSR_TVEC, context->tvec); + csr_write(CSR_IE, context->ie); + +#ifdef CONFIG_MMU + csr_write(CSR_SATP, context->satp); +#endif +} + +int cpu_suspend(unsigned long arg, + int (*finish)(unsigned long arg, + unsigned long entry, + unsigned long context)) +{ + int rc = 0; + struct suspend_context context = { 0 }; + + /* Finisher should be non-NULL */ + if (!finish) + return -EINVAL; + + /* Save additional CSRs*/ + suspend_save_csrs(&context); + + /* + * Function graph tracer state gets incosistent when the kernel + * calls functions that never return (aka finishers) hence disable + * graph tracing during their execution. + */ + pause_graph_tracing(); + + /* Save context on stack */ + if (__cpu_suspend_enter(&context)) { + /* Call the finisher */ + rc = finish(arg, __pa_symbol(__cpu_resume_enter), + (ulong)&context); + + /* + * Should never reach here, unless the suspend finisher + * fails. Successful cpu_suspend() should return from + * __cpu_resume_entry() + */ + if (!rc) + rc = -EOPNOTSUPP; + } + + /* Enable function graph tracer */ + unpause_graph_tracing(); + + /* Restore additional CSRs */ + suspend_restore_csrs(&context); + + return rc; +} diff --git a/arch/riscv/kernel/suspend_entry.S b/arch/riscv/kernel/suspend_entry.S new file mode 100644 index 000000000000..4b07b809a2b8 --- /dev/null +++ b/arch/riscv/kernel/suspend_entry.S @@ -0,0 +1,124 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * Copyright (c) 2022 Ventana Micro Systems Inc. + */ + +#include <linux/linkage.h> +#include <asm/asm.h> +#include <asm/asm-offsets.h> +#include <asm/csr.h> + + .text + .altmacro + .option norelax + +ENTRY(__cpu_suspend_enter) + /* Save registers (except A0 and T0-T6) */ + REG_S ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0) + REG_S sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0) + REG_S gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0) + REG_S tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0) + REG_S s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0) + REG_S s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0) + REG_S a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0) + REG_S a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0) + REG_S a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0) + REG_S a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0) + REG_S a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0) + REG_S a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0) + REG_S a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0) + REG_S s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0) + REG_S s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0) + REG_S s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0) + REG_S s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0) + REG_S s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0) + REG_S s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0) + REG_S s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0) + REG_S s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0) + REG_S s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0) + REG_S s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0) + + /* Save CSRs */ + csrr t0, CSR_EPC + REG_S t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0) + csrr t0, CSR_STATUS + REG_S t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0) + csrr t0, CSR_TVAL + REG_S t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0) + csrr t0, CSR_CAUSE + REG_S t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0) + + /* Return non-zero value */ + li a0, 1 + + /* Return to C code */ + ret +END(__cpu_suspend_enter) + +ENTRY(__cpu_resume_enter) + /* Load the global pointer */ + .option push + .option norelax + la gp, __global_pointer$ + .option pop + +#ifdef CONFIG_MMU + /* Save A0 and A1 */ + add t0, a0, zero + add t1, a1, zero + + /* Enable MMU */ + la a0, swapper_pg_dir + XIP_FIXUP_OFFSET a0 + call relocate_enable_mmu + + /* Restore A0 and A1 */ + add a0, t0, zero + add a1, t1, zero +#endif + + /* Make A0 point to suspend context */ + add a0, a1, zero + + /* Restore CSRs */ + REG_L t0, (SUSPEND_CONTEXT_REGS + PT_EPC)(a0) + csrw CSR_EPC, t0 + REG_L t0, (SUSPEND_CONTEXT_REGS + PT_STATUS)(a0) + csrw CSR_STATUS, t0 + REG_L t0, (SUSPEND_CONTEXT_REGS + PT_BADADDR)(a0) + csrw CSR_TVAL, t0 + REG_L t0, (SUSPEND_CONTEXT_REGS + PT_CAUSE)(a0) + csrw CSR_CAUSE, t0 + + /* Restore registers (except A0 and T0-T6) */ + REG_L ra, (SUSPEND_CONTEXT_REGS + PT_RA)(a0) + REG_L sp, (SUSPEND_CONTEXT_REGS + PT_SP)(a0) + REG_L gp, (SUSPEND_CONTEXT_REGS + PT_GP)(a0) + REG_L tp, (SUSPEND_CONTEXT_REGS + PT_TP)(a0) + REG_L s0, (SUSPEND_CONTEXT_REGS + PT_S0)(a0) + REG_L s1, (SUSPEND_CONTEXT_REGS + PT_S1)(a0) + REG_L a1, (SUSPEND_CONTEXT_REGS + PT_A1)(a0) + REG_L a2, (SUSPEND_CONTEXT_REGS + PT_A2)(a0) + REG_L a3, (SUSPEND_CONTEXT_REGS + PT_A3)(a0) + REG_L a4, (SUSPEND_CONTEXT_REGS + PT_A4)(a0) + REG_L a5, (SUSPEND_CONTEXT_REGS + PT_A5)(a0) + REG_L a6, (SUSPEND_CONTEXT_REGS + PT_A6)(a0) + REG_L a7, (SUSPEND_CONTEXT_REGS + PT_A7)(a0) + REG_L s2, (SUSPEND_CONTEXT_REGS + PT_S2)(a0) + REG_L s3, (SUSPEND_CONTEXT_REGS + PT_S3)(a0) + REG_L s4, (SUSPEND_CONTEXT_REGS + PT_S4)(a0) + REG_L s5, (SUSPEND_CONTEXT_REGS + PT_S5)(a0) + REG_L s6, (SUSPEND_CONTEXT_REGS + PT_S6)(a0) + REG_L s7, (SUSPEND_CONTEXT_REGS + PT_S7)(a0) + REG_L s8, (SUSPEND_CONTEXT_REGS + PT_S8)(a0) + REG_L s9, (SUSPEND_CONTEXT_REGS + PT_S9)(a0) + REG_L s10, (SUSPEND_CONTEXT_REGS + PT_S10)(a0) + REG_L s11, (SUSPEND_CONTEXT_REGS + PT_S11)(a0) + + /* Return zero value */ + add a0, zero, zero + + /* Return to C code */ + ret +END(__cpu_resume_enter) |