1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 *  arch/arm/include/asm/proc-fns.h
  4 *
  5 *  Copyright (C) 1997-1999 Russell King
  6 *  Copyright (C) 2000 Deep Blue Solutions Ltd
  7 */
  8#ifndef __ASM_PROCFNS_H
  9#define __ASM_PROCFNS_H
 10
 11#ifdef __KERNEL__
 12
 13#include <asm/glue-proc.h>
 14#include <asm/page.h>
 15
 16#ifndef __ASSEMBLY__
 17
 18struct mm_struct;
 19
 20/*
 21 * Don't change this structure - ASM code relies on it.
 22 */
 23struct processor {
 24	/* MISC
 25	 * get data abort address/flags
 26	 */
 27	void (*_data_abort)(unsigned long pc);
 28	/*
 29	 * Retrieve prefetch fault address
 30	 */
 31	unsigned long (*_prefetch_abort)(unsigned long lr);
 32	/*
 33	 * Set up any processor specifics
 34	 */
 35	void (*_proc_init)(void);
 36	/*
 37	 * Check for processor bugs
 38	 */
 39	void (*check_bugs)(void);
 40	/*
 41	 * Disable any processor specifics
 42	 */
 43	void (*_proc_fin)(void);
 44	/*
 45	 * Special stuff for a reset
 46	 */
 47	void (*reset)(unsigned long addr, bool hvc) __attribute__((noreturn));
 48	/*
 49	 * Idle the processor
 50	 */
 51	int (*_do_idle)(void);
 52	/*
 53	 * Processor architecture specific
 54	 */
 55	/*
 56	 * clean a virtual address range from the
 57	 * D-cache without flushing the cache.
 58	 */
 59	void (*dcache_clean_area)(void *addr, int size);
 60
 61	/*
 62	 * Set the page table
 63	 */
 64	void (*switch_mm)(phys_addr_t pgd_phys, struct mm_struct *mm);
 65	/*
 66	 * Set a possibly extended PTE.  Non-extended PTEs should
 67	 * ignore 'ext'.
 68	 */
 69#ifdef CONFIG_ARM_LPAE
 70	void (*set_pte_ext)(pte_t *ptep, pte_t pte);
 71#else
 72	void (*set_pte_ext)(pte_t *ptep, pte_t pte, unsigned int ext);
 73#endif
 74
 75	/* Suspend/resume */
 76	unsigned int suspend_size;
 77	void (*do_suspend)(void *);
 78	void (*do_resume)(void *);
 79};
 80
 81#ifndef MULTI_CPU
 82static inline void init_proc_vtable(const struct processor *p)
 83{
 84}
 85
 86extern void cpu_proc_init(void);
 87extern void cpu_proc_fin(void);
 88extern int cpu_do_idle(void);
 89extern void cpu_dcache_clean_area(void *, int);
 90extern void cpu_do_switch_mm(phys_addr_t pgd_phys, struct mm_struct *mm);
 91#ifdef CONFIG_ARM_LPAE
 92extern void cpu_set_pte_ext(pte_t *ptep, pte_t pte);
 93#else
 94extern void cpu_set_pte_ext(pte_t *ptep, pte_t pte, unsigned int ext);
 95#endif
 96extern void cpu_reset(unsigned long addr, bool hvc) __attribute__((noreturn));
 97
 98/* These three are private to arch/arm/kernel/suspend.c */
 99extern void cpu_do_suspend(void *);
100extern void cpu_do_resume(void *);
101#else
102
103extern struct processor processor;
104#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR)
105#include <linux/smp.h>
106/*
107 * This can't be a per-cpu variable because we need to access it before
108 * per-cpu has been initialised.  We have a couple of functions that are
109 * called in a pre-emptible context, and so can't use smp_processor_id()
110 * there, hence PROC_TABLE().  We insist in init_proc_vtable() that the
111 * function pointers for these are identical across all CPUs.
112 */
113extern struct processor *cpu_vtable[];
114#define PROC_VTABLE(f)			cpu_vtable[smp_processor_id()]->f
115#define PROC_TABLE(f)			cpu_vtable[0]->f
116static inline void init_proc_vtable(const struct processor *p)
117{
118	unsigned int cpu = smp_processor_id();
119	*cpu_vtable[cpu] = *p;
120	WARN_ON_ONCE(cpu_vtable[cpu]->dcache_clean_area !=
121		     cpu_vtable[0]->dcache_clean_area);
122	WARN_ON_ONCE(cpu_vtable[cpu]->set_pte_ext !=
123		     cpu_vtable[0]->set_pte_ext);
124}
125#else
126#define PROC_VTABLE(f)			processor.f
127#define PROC_TABLE(f)			processor.f
128static inline void init_proc_vtable(const struct processor *p)
129{
130	processor = *p;
131}
132#endif
133
134#define cpu_proc_init			PROC_VTABLE(_proc_init)
135#define cpu_check_bugs			PROC_VTABLE(check_bugs)
136#define cpu_proc_fin			PROC_VTABLE(_proc_fin)
137#define cpu_reset			PROC_VTABLE(reset)
138#define cpu_do_idle			PROC_VTABLE(_do_idle)
139#define cpu_dcache_clean_area		PROC_TABLE(dcache_clean_area)
140#define cpu_set_pte_ext			PROC_TABLE(set_pte_ext)
141#define cpu_do_switch_mm		PROC_VTABLE(switch_mm)
142
143/* These two are private to arch/arm/kernel/suspend.c */
144#define cpu_do_suspend			PROC_VTABLE(do_suspend)
145#define cpu_do_resume			PROC_VTABLE(do_resume)
146#endif
147
148extern void cpu_resume(void);
149
150#ifdef CONFIG_MMU
151
152#define cpu_switch_mm(pgd,mm) cpu_do_switch_mm(virt_to_phys(pgd),mm)
153
154#ifdef CONFIG_ARM_LPAE
155
156#define cpu_get_ttbr(nr)					\
157	({							\
158		u64 ttbr;					\
159		__asm__("mrrc	p15, " #nr ", %Q0, %R0, c2"	\
160			: "=r" (ttbr));				\
161		ttbr;						\
162	})
163
164#define cpu_get_pgd()	\
165	({						\
166		u64 pg = cpu_get_ttbr(0);		\
167		pg &= ~(PTRS_PER_PGD*sizeof(pgd_t)-1);	\
168		(pgd_t *)phys_to_virt(pg);		\
169	})
170#else
171#define cpu_get_pgd()	\
172	({						\
173		unsigned long pg;			\
174		__asm__("mrc	p15, 0, %0, c2, c0, 0"	\
175			 : "=r" (pg) : : "cc");		\
176		pg &= ~0x3fff;				\
177		(pgd_t *)phys_to_virt(pg);		\
178	})
179#endif
180
181#else	/*!CONFIG_MMU */
182
183#define cpu_switch_mm(pgd,mm)	{ }
184
185#endif
186
187#endif /* __ASSEMBLY__ */
188#endif /* __KERNEL__ */
189#endif /* __ASM_PROCFNS_H */