xref: /linux/arch/riscv/include/asm/processor.h (revision d4abde52b4b116111537593e2744b3234d18808d)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2012 Regents of the University of California
4  */
5 
6 #ifndef _ASM_RISCV_PROCESSOR_H
7 #define _ASM_RISCV_PROCESSOR_H
8 
9 #include <linux/const.h>
10 #include <linux/cache.h>
11 #include <linux/prctl.h>
12 
13 #include <vdso/processor.h>
14 
15 #include <asm/ptrace.h>
16 
17 #ifdef CONFIG_64BIT
18 #define DEFAULT_MAP_WINDOW	(UL(1) << (MMAP_VA_BITS - 1))
19 #define STACK_TOP_MAX		TASK_SIZE
20 
21 #define arch_get_mmap_end(addr, len, flags)			\
22 ({								\
23 	unsigned long mmap_end;					\
24 	typeof(addr) _addr = (addr);				\
25 	if ((_addr) == 0 || (IS_ENABLED(CONFIG_COMPAT) && is_compat_task())) \
26 		mmap_end = STACK_TOP_MAX;			\
27 	else if ((_addr) >= VA_USER_SV57)			\
28 		mmap_end = STACK_TOP_MAX;			\
29 	else if ((((_addr) >= VA_USER_SV48)) && (VA_BITS >= VA_BITS_SV48)) \
30 		mmap_end = VA_USER_SV48;			\
31 	else							\
32 		mmap_end = VA_USER_SV39;			\
33 	mmap_end;						\
34 })
35 
36 #define arch_get_mmap_base(addr, base)				\
37 ({								\
38 	unsigned long mmap_base;				\
39 	typeof(addr) _addr = (addr);				\
40 	typeof(base) _base = (base);				\
41 	unsigned long rnd_gap = DEFAULT_MAP_WINDOW - (_base);	\
42 	if ((_addr) == 0 || (IS_ENABLED(CONFIG_COMPAT) && is_compat_task())) \
43 		mmap_base = (_base);				\
44 	else if (((_addr) >= VA_USER_SV57) && (VA_BITS >= VA_BITS_SV57)) \
45 		mmap_base = VA_USER_SV57 - rnd_gap;		\
46 	else if ((((_addr) >= VA_USER_SV48)) && (VA_BITS >= VA_BITS_SV48)) \
47 		mmap_base = VA_USER_SV48 - rnd_gap;		\
48 	else							\
49 		mmap_base = VA_USER_SV39 - rnd_gap;		\
50 	mmap_base;						\
51 })
52 
53 #else
54 #define DEFAULT_MAP_WINDOW	TASK_SIZE
55 #define STACK_TOP_MAX		TASK_SIZE
56 #endif
57 #define STACK_ALIGN		16
58 
59 #define STACK_TOP		DEFAULT_MAP_WINDOW
60 
61 /*
62  * This decides where the kernel will search for a free chunk of vm
63  * space during mmap's.
64  */
65 #ifdef CONFIG_64BIT
66 #define TASK_UNMAPPED_BASE	PAGE_ALIGN((UL(1) << MMAP_MIN_VA_BITS) / 3)
67 #else
68 #define TASK_UNMAPPED_BASE	PAGE_ALIGN(TASK_SIZE / 3)
69 #endif
70 
71 #ifndef __ASSEMBLY__
72 
73 struct task_struct;
74 struct pt_regs;
75 
76 /* CPU-specific state of a task */
77 struct thread_struct {
78 	/* Callee-saved registers */
79 	unsigned long ra;
80 	unsigned long sp;	/* Kernel mode stack */
81 	unsigned long s[12];	/* s[0]: frame pointer */
82 	struct __riscv_d_ext_state fstate;
83 	unsigned long bad_cause;
84 	unsigned long vstate_ctrl;
85 	struct __riscv_v_ext_state vstate;
86 	unsigned long align_ctl;
87 };
88 
89 /* Whitelist the fstate from the task_struct for hardened usercopy */
90 static inline void arch_thread_struct_whitelist(unsigned long *offset,
91 						unsigned long *size)
92 {
93 	*offset = offsetof(struct thread_struct, fstate);
94 	*size = sizeof_field(struct thread_struct, fstate);
95 }
96 
97 #define INIT_THREAD {					\
98 	.sp = sizeof(init_stack) + (long)&init_stack,	\
99 	.align_ctl = PR_UNALIGN_NOPRINT,		\
100 }
101 
102 #define task_pt_regs(tsk)						\
103 	((struct pt_regs *)(task_stack_page(tsk) + THREAD_SIZE		\
104 			    - ALIGN(sizeof(struct pt_regs), STACK_ALIGN)))
105 
106 #define KSTK_EIP(tsk)		(task_pt_regs(tsk)->epc)
107 #define KSTK_ESP(tsk)		(task_pt_regs(tsk)->sp)
108 
109 
110 /* Do necessary setup to start up a newly executed thread. */
111 extern void start_thread(struct pt_regs *regs,
112 			unsigned long pc, unsigned long sp);
113 
114 extern unsigned long __get_wchan(struct task_struct *p);
115 
116 
117 static inline void wait_for_interrupt(void)
118 {
119 	__asm__ __volatile__ ("wfi");
120 }
121 
122 extern phys_addr_t dma32_phys_limit;
123 
124 struct device_node;
125 int riscv_of_processor_hartid(struct device_node *node, unsigned long *hartid);
126 int riscv_early_of_processor_hartid(struct device_node *node, unsigned long *hartid);
127 int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid);
128 
129 extern void riscv_fill_hwcap(void);
130 extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
131 
132 extern unsigned long signal_minsigstksz __ro_after_init;
133 
134 #ifdef CONFIG_RISCV_ISA_V
135 /* Userspace interface for PR_RISCV_V_{SET,GET}_VS prctl()s: */
136 #define RISCV_V_SET_CONTROL(arg)	riscv_v_vstate_ctrl_set_current(arg)
137 #define RISCV_V_GET_CONTROL()		riscv_v_vstate_ctrl_get_current()
138 extern long riscv_v_vstate_ctrl_set_current(unsigned long arg);
139 extern long riscv_v_vstate_ctrl_get_current(void);
140 #endif /* CONFIG_RISCV_ISA_V */
141 
142 extern int get_unalign_ctl(struct task_struct *tsk, unsigned long addr);
143 extern int set_unalign_ctl(struct task_struct *tsk, unsigned int val);
144 
145 #define GET_UNALIGN_CTL(tsk, addr)	get_unalign_ctl((tsk), (addr))
146 #define SET_UNALIGN_CTL(tsk, val)	set_unalign_ctl((tsk), (val))
147 
148 #endif /* __ASSEMBLY__ */
149 
150 #endif /* _ASM_RISCV_PROCESSOR_H */
151