1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4  */
5 #ifndef _ASM_PROCESSOR_H
6 #define _ASM_PROCESSOR_H
7 
8 #include <linux/atomic.h>
9 #include <linux/cpumask.h>
10 #include <linux/sizes.h>
11 
12 #include <asm/cpu.h>
13 #include <asm/cpu-info.h>
14 #include <asm/loongarch.h>
15 #include <asm/vdso/processor.h>
16 #include <uapi/asm/ptrace.h>
17 #include <uapi/asm/sigcontext.h>
18 
19 #ifdef CONFIG_32BIT
20 
21 #define TASK_SIZE	0x80000000UL
22 #define TASK_SIZE_MIN	TASK_SIZE
23 #define STACK_TOP_MAX	TASK_SIZE
24 
25 #define TASK_IS_32BIT_ADDR 1
26 
27 #endif
28 
29 #ifdef CONFIG_64BIT
30 
31 #define TASK_SIZE32	0x100000000UL
32 #define TASK_SIZE64     (0x1UL << ((cpu_vabits > VA_BITS) ? VA_BITS : cpu_vabits))
33 
34 #define TASK_SIZE	(test_thread_flag(TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
35 #define TASK_SIZE_MIN	TASK_SIZE32
36 #define STACK_TOP_MAX	TASK_SIZE64
37 
38 #define TASK_SIZE_OF(tsk)						\
39 	(test_tsk_thread_flag(tsk, TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE64)
40 
41 #define TASK_IS_32BIT_ADDR test_thread_flag(TIF_32BIT_ADDR)
42 
43 #endif
44 
45 #define VDSO_RANDOMIZE_SIZE	(TASK_IS_32BIT_ADDR ? SZ_1M : SZ_64M)
46 
47 unsigned long stack_top(void);
48 #define STACK_TOP stack_top()
49 
50 /*
51  * This decides where the kernel will search for a free chunk of vm
52  * space during mmap's.
53  */
54 #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)
55 
56 #define FPU_REG_WIDTH		256
57 #define FPU_ALIGN		__attribute__((aligned(32)))
58 
59 union fpureg {
60 	__u32	val32[FPU_REG_WIDTH / 32];
61 	__u64	val64[FPU_REG_WIDTH / 64];
62 };
63 
64 #define FPR_IDX(width, idx)	(idx)
65 
66 #define BUILD_FPR_ACCESS(width) \
67 static inline u##width get_fpr##width(union fpureg *fpr, unsigned idx)	\
68 {									\
69 	return fpr->val##width[FPR_IDX(width, idx)];			\
70 }									\
71 									\
72 static inline void set_fpr##width(union fpureg *fpr, unsigned int idx,	\
73 				  u##width val)				\
74 {									\
75 	fpr->val##width[FPR_IDX(width, idx)] = val;			\
76 }
77 
78 BUILD_FPR_ACCESS(32)
79 BUILD_FPR_ACCESS(64)
80 
81 struct loongarch_fpu {
82 	unsigned int	fcsr;
83 	uint64_t	fcc;	/* 8x8 */
84 	union fpureg	fpr[NUM_FPU_REGS];
85 };
86 
87 #define INIT_CPUMASK { \
88 	{0,} \
89 }
90 
91 #define ARCH_MIN_TASKALIGN	32
92 
93 struct loongarch_vdso_info;
94 
95 /*
96  * If you change thread_struct remember to change the #defines below too!
97  */
98 struct thread_struct {
99 	/* Main processor registers. */
100 	unsigned long reg01, reg03, reg22; /* ra sp fp */
101 	unsigned long reg23, reg24, reg25, reg26; /* s0-s3 */
102 	unsigned long reg27, reg28, reg29, reg30, reg31; /* s4-s8 */
103 
104 	/* __schedule() return address / call frame address */
105 	unsigned long sched_ra;
106 	unsigned long sched_cfa;
107 
108 	/* CSR registers */
109 	unsigned long csr_prmd;
110 	unsigned long csr_crmd;
111 	unsigned long csr_euen;
112 	unsigned long csr_ecfg;
113 	unsigned long csr_badvaddr;	/* Last user fault */
114 
115 	/* Scratch registers */
116 	unsigned long scr0;
117 	unsigned long scr1;
118 	unsigned long scr2;
119 	unsigned long scr3;
120 
121 	/* Eflags register */
122 	unsigned long eflags;
123 
124 	/* Other stuff associated with the thread. */
125 	unsigned long trap_nr;
126 	unsigned long error_code;
127 	struct loongarch_vdso_info *vdso;
128 
129 	/*
130 	 * FPU & vector registers, must be at last because
131 	 * they are conditionally copied at fork().
132 	 */
133 	struct loongarch_fpu fpu FPU_ALIGN;
134 };
135 
136 #define thread_saved_ra(tsk)	(tsk->thread.sched_ra)
137 #define thread_saved_fp(tsk)	(tsk->thread.sched_cfa)
138 
139 #define INIT_THREAD  {						\
140 	/*							\
141 	 * Main processor registers				\
142 	 */							\
143 	.reg01			= 0,				\
144 	.reg03			= 0,				\
145 	.reg22			= 0,				\
146 	.reg23			= 0,				\
147 	.reg24			= 0,				\
148 	.reg25			= 0,				\
149 	.reg26			= 0,				\
150 	.reg27			= 0,				\
151 	.reg28			= 0,				\
152 	.reg29			= 0,				\
153 	.reg30			= 0,				\
154 	.reg31			= 0,				\
155 	.sched_ra		= 0,				\
156 	.sched_cfa		= 0,				\
157 	.csr_crmd		= 0,				\
158 	.csr_prmd		= 0,				\
159 	.csr_euen		= 0,				\
160 	.csr_ecfg		= 0,				\
161 	.csr_badvaddr		= 0,				\
162 	/*							\
163 	 * Other stuff associated with the process		\
164 	 */							\
165 	.trap_nr		= 0,				\
166 	.error_code		= 0,				\
167 	/*							\
168 	 * FPU & vector registers				\
169 	 */							\
170 	.fpu			= {				\
171 		.fcsr		= 0,				\
172 		.fcc		= 0,				\
173 		.fpr		= {{{0,},},},			\
174 	},							\
175 }
176 
177 struct task_struct;
178 
179 enum idle_boot_override {IDLE_NO_OVERRIDE = 0, IDLE_HALT, IDLE_NOMWAIT, IDLE_POLL};
180 
181 extern unsigned long		boot_option_idle_override;
182 /*
183  * Do necessary setup to start up a newly executed thread.
184  */
185 extern void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp);
186 
flush_thread(void)187 static inline void flush_thread(void)
188 {
189 }
190 
191 unsigned long __get_wchan(struct task_struct *p);
192 
193 #define __KSTK_TOS(tsk) ((unsigned long)task_stack_page(tsk) + \
194 			 THREAD_SIZE - sizeof(struct pt_regs))
195 #define task_pt_regs(tsk) ((struct pt_regs *)__KSTK_TOS(tsk))
196 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->csr_era)
197 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->regs[3])
198 #define KSTK_EUEN(tsk) (task_pt_regs(tsk)->csr_euen)
199 #define KSTK_ECFG(tsk) (task_pt_regs(tsk)->csr_ecfg)
200 
201 #define return_address() ({__asm__ __volatile__("":::"$1"); __builtin_return_address(0);})
202 
203 #ifdef CONFIG_CPU_HAS_PREFETCH
204 
205 #define ARCH_HAS_PREFETCH
206 #define prefetch(x) __builtin_prefetch((x), 0, 1)
207 
208 #define ARCH_HAS_PREFETCHW
209 #define prefetchw(x) __builtin_prefetch((x), 1, 1)
210 
211 #endif
212 
213 #endif /* _ASM_PROCESSOR_H */
214