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Diffstat (limited to 'arch/riscv/include/asm/processor.h')
| -rw-r--r-- | arch/riscv/include/asm/processor.h | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h new file mode 100644 index 000000000000..da5426122d28 --- /dev/null +++ b/arch/riscv/include/asm/processor.h @@ -0,0 +1,220 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2012 Regents of the University of California + */ + +#ifndef _ASM_RISCV_PROCESSOR_H +#define _ASM_RISCV_PROCESSOR_H + +#include <linux/const.h> +#include <linux/cache.h> +#include <linux/prctl.h> + +#include <vdso/processor.h> + +#include <asm/ptrace.h> +#include <asm/insn-def.h> +#include <asm/alternative-macros.h> +#include <asm/hwcap.h> + +#define arch_get_mmap_end(addr, len, flags) \ +({ \ + STACK_TOP_MAX; \ +}) + +#define arch_get_mmap_base(addr, base) \ +({ \ + base; \ +}) + +#ifdef CONFIG_64BIT +#define DEFAULT_MAP_WINDOW (UL(1) << (MMAP_VA_BITS - 1)) +#define STACK_TOP_MAX TASK_SIZE_64 +#else +#define DEFAULT_MAP_WINDOW TASK_SIZE +#define STACK_TOP_MAX TASK_SIZE +#endif +#define STACK_ALIGN 16 + +#define STACK_TOP DEFAULT_MAP_WINDOW + +#ifdef CONFIG_MMU +#define user_max_virt_addr() arch_get_mmap_end(ULONG_MAX, 0, 0) +#else +#define user_max_virt_addr() 0 +#endif /* CONFIG_MMU */ + +/* + * This decides where the kernel will search for a free chunk of vm + * space during mmap's. + */ +#ifdef CONFIG_64BIT +#define TASK_UNMAPPED_BASE PAGE_ALIGN((UL(1) << MMAP_MIN_VA_BITS) / 3) +#else +#define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3) +#endif + +#ifndef __ASSEMBLER__ + +struct task_struct; +struct pt_regs; + +/* + * We use a flag to track in-kernel Vector context. Currently the flag has the + * following meaning: + * + * - bit 0: indicates whether the in-kernel Vector context is active. The + * activation of this state disables the preemption. On a non-RT kernel, it + * also disable bh. + * - bits 8: is used for tracking preemptible kernel-mode Vector, when + * RISCV_ISA_V_PREEMPTIVE is enabled. Calling kernel_vector_begin() does not + * disable the preemption if the thread's kernel_vstate.datap is allocated. + * Instead, the kernel set this bit field. Then the trap entry/exit code + * knows if we are entering/exiting the context that owns preempt_v. + * - 0: the task is not using preempt_v + * - 1: the task is actively using preempt_v. But whether does the task own + * the preempt_v context is decided by bits in RISCV_V_CTX_DEPTH_MASK. + * - bit 16-23 are RISCV_V_CTX_DEPTH_MASK, used by context tracking routine + * when preempt_v starts: + * - 0: the task is actively using, and own preempt_v context. + * - non-zero: the task was using preempt_v, but then took a trap within. + * Thus, the task does not own preempt_v. Any use of Vector will have to + * save preempt_v, if dirty, and fallback to non-preemptible kernel-mode + * Vector. + * - bit 29: The thread voluntarily calls schedule() while holding an active + * preempt_v. All preempt_v context should be dropped in such case because + * V-regs are caller-saved. Only sstatus.VS=ON is persisted across a + * schedule() call. + * - bit 30: The in-kernel preempt_v context is saved, and requries to be + * restored when returning to the context that owns the preempt_v. + * - bit 31: The in-kernel preempt_v context is dirty, as signaled by the + * trap entry code. Any context switches out-of current task need to save + * it to the task's in-kernel V context. Also, any traps nesting on-top-of + * preempt_v requesting to use V needs a save. + */ +#define RISCV_V_CTX_DEPTH_MASK 0x00ff0000 + +#define RISCV_V_CTX_UNIT_DEPTH 0x00010000 +#define RISCV_KERNEL_MODE_V 0x00000001 +#define RISCV_PREEMPT_V 0x00000100 +#define RISCV_PREEMPT_V_DIRTY 0x80000000 +#define RISCV_PREEMPT_V_NEED_RESTORE 0x40000000 +#define RISCV_PREEMPT_V_IN_SCHEDULE 0x20000000 + +/* CPU-specific state of a task */ +struct thread_struct { + /* Callee-saved registers */ + unsigned long ra; + unsigned long sp; /* Kernel mode stack */ + unsigned long s[12]; /* s[0]: frame pointer */ + struct __riscv_d_ext_state fstate; + unsigned long bad_cause; + unsigned long envcfg; + unsigned long sum; + u32 riscv_v_flags; + u32 vstate_ctrl; + struct __riscv_v_ext_state vstate; + unsigned long align_ctl; + struct __riscv_v_ext_state kernel_vstate; +#ifdef CONFIG_SMP + /* Flush the icache on migration */ + bool force_icache_flush; + /* A forced icache flush is not needed if migrating to the previous cpu. */ + unsigned int prev_cpu; +#endif +}; + +/* Whitelist the fstate from the task_struct for hardened usercopy */ +static inline void arch_thread_struct_whitelist(unsigned long *offset, + unsigned long *size) +{ + *offset = offsetof(struct thread_struct, fstate); + *size = sizeof_field(struct thread_struct, fstate); +} + +#define INIT_THREAD { \ + .sp = sizeof(init_stack) + (long)&init_stack, \ + .align_ctl = PR_UNALIGN_NOPRINT, \ +} + +#define task_pt_regs(tsk) \ + ((struct pt_regs *)(task_stack_page(tsk) + THREAD_SIZE \ + - ALIGN(sizeof(struct pt_regs), STACK_ALIGN))) + +#define KSTK_EIP(tsk) (task_pt_regs(tsk)->epc) +#define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp) + +#define PREFETCH_ASM(x) \ + ALTERNATIVE(__nops(1), PREFETCH_R(x, 0), 0, \ + RISCV_ISA_EXT_ZICBOP, CONFIG_RISCV_ISA_ZICBOP) + +#define PREFETCHW_ASM(x) \ + ALTERNATIVE(__nops(1), PREFETCH_W(x, 0), 0, \ + RISCV_ISA_EXT_ZICBOP, CONFIG_RISCV_ISA_ZICBOP) + +#ifdef CONFIG_RISCV_ISA_ZICBOP +#define ARCH_HAS_PREFETCH +static inline void prefetch(const void *x) +{ + __asm__ __volatile__(PREFETCH_ASM(%0) : : "r" (x) : "memory"); +} + +#define ARCH_HAS_PREFETCHW +static inline void prefetchw(const void *x) +{ + __asm__ __volatile__(PREFETCHW_ASM(%0) : : "r" (x) : "memory"); +} +#endif /* CONFIG_RISCV_ISA_ZICBOP */ + +/* Do necessary setup to start up a newly executed thread. */ +extern void start_thread(struct pt_regs *regs, + unsigned long pc, unsigned long sp); + +extern unsigned long __get_wchan(struct task_struct *p); + + +static inline void wait_for_interrupt(void) +{ + __asm__ __volatile__ ("wfi"); +} + +extern phys_addr_t dma32_phys_limit; + +struct device_node; +int riscv_of_processor_hartid(struct device_node *node, unsigned long *hartid); +int riscv_early_of_processor_hartid(struct device_node *node, unsigned long *hartid); +int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid); + +extern void riscv_fill_hwcap(void); +extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); + +extern unsigned long signal_minsigstksz __ro_after_init; + +#ifdef CONFIG_RISCV_ISA_V +/* Userspace interface for PR_RISCV_V_{SET,GET}_VS prctl()s: */ +#define RISCV_V_SET_CONTROL(arg) riscv_v_vstate_ctrl_set_current(arg) +#define RISCV_V_GET_CONTROL() riscv_v_vstate_ctrl_get_current() +extern long riscv_v_vstate_ctrl_set_current(unsigned long arg); +extern long riscv_v_vstate_ctrl_get_current(void); +#endif /* CONFIG_RISCV_ISA_V */ + +extern int get_unalign_ctl(struct task_struct *tsk, unsigned long addr); +extern int set_unalign_ctl(struct task_struct *tsk, unsigned int val); + +#define GET_UNALIGN_CTL(tsk, addr) get_unalign_ctl((tsk), (addr)) +#define SET_UNALIGN_CTL(tsk, val) set_unalign_ctl((tsk), (val)) + +#define RISCV_SET_ICACHE_FLUSH_CTX(arg1, arg2) riscv_set_icache_flush_ctx(arg1, arg2) +extern int riscv_set_icache_flush_ctx(unsigned long ctx, unsigned long per_thread); + +#ifdef CONFIG_RISCV_ISA_SUPM +/* PR_{SET,GET}_TAGGED_ADDR_CTRL prctl */ +long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg); +long get_tagged_addr_ctrl(struct task_struct *task); +#define SET_TAGGED_ADDR_CTRL(arg) set_tagged_addr_ctrl(current, arg) +#define GET_TAGGED_ADDR_CTRL() get_tagged_addr_ctrl(current) +#endif + +#endif /* __ASSEMBLER__ */ + +#endif /* _ASM_RISCV_PROCESSOR_H */ |