/* SPDX-License-Identifier: GPL-2.0-only */
/*
 *  arch/arm/include/asm/proc-fns.h
 *
 *  Copyright (C) 1997-1999 Russell King
 *  Copyright (C) 2000 Deep Blue Solutions Ltd
 */
#ifndef __ASM_PROCFNS_H
#define __ASM_PROCFNS_H

#ifdef __KERNEL__

#include <asm/glue-proc.h>
#include <asm/page.h>

#ifndef __ASSEMBLY__

struct mm_struct;

/*
 * Don't change this structure - ASM code relies on it.
 */
struct processor {
        /* MISC
         * get data abort address/flags
         */
        void (*_data_abort)(unsigned long pc);
        /*
         * Retrieve prefetch fault address
         */
        unsigned long (*_prefetch_abort)(unsigned long lr);
        /*
         * Set up any processor specifics
         */
        void (*_proc_init)(void);
        /*
         * Check for processor bugs
         */
        void (*check_bugs)(void);
        /*
         * Disable any processor specifics
         */
        void (*_proc_fin)(void);
        /*
         * Special stuff for a reset
         */
        void (*reset)(unsigned long addr, bool hvc) __attribute__((noreturn));
        /*
         * Idle the processor
         */
        int (*_do_idle)(void);
        /*
         * Processor architecture specific
         */
        /*
         * clean a virtual address range from the
         * D-cache without flushing the cache.
         */
        void (*dcache_clean_area)(void *addr, int size);

        /*
         * Set the page table
         */
        void (*switch_mm)(phys_addr_t pgd_phys, struct mm_struct *mm);
        /*
         * Set a possibly extended PTE.  Non-extended PTEs should
         * ignore 'ext'.
         */
#ifdef CONFIG_ARM_LPAE
        void (*set_pte_ext)(pte_t *ptep, pte_t pte);
#else
        void (*set_pte_ext)(pte_t *ptep, pte_t pte, unsigned int ext);
#endif

        /* Suspend/resume */
        unsigned int suspend_size;
        void (*do_suspend)(void *);
        void (*do_resume)(void *);
};

#ifndef MULTI_CPU
static inline void init_proc_vtable(const struct processor *p)
{
}

extern void cpu_proc_init(void);
extern void cpu_proc_fin(void);
extern int cpu_do_idle(void);
extern void cpu_dcache_clean_area(void *, int);
extern void cpu_do_switch_mm(phys_addr_t pgd_phys, struct mm_struct *mm);
#ifdef CONFIG_ARM_LPAE
extern void cpu_set_pte_ext(pte_t *ptep, pte_t pte);
#else
extern void cpu_set_pte_ext(pte_t *ptep, pte_t pte, unsigned int ext);
#endif
extern void cpu_reset(unsigned long addr, bool hvc) __attribute__((noreturn));

/* These three are private to arch/arm/kernel/suspend.c */
extern void cpu_do_suspend(void *);
extern void cpu_do_resume(void *);
#else

extern struct processor processor;
#if defined(CONFIG_BIG_LITTLE) && defined(CONFIG_HARDEN_BRANCH_PREDICTOR)
#include <linux/smp.h>
/*
 * This can't be a per-cpu variable because we need to access it before
 * per-cpu has been initialised.  We have a couple of functions that are
 * called in a pre-emptible context, and so can't use smp_processor_id()
 * there, hence PROC_TABLE().  We insist in init_proc_vtable() that the
 * function pointers for these are identical across all CPUs.
 */
extern struct processor *cpu_vtable[];
#define PROC_VTABLE(f)                  cpu_vtable[smp_processor_id()]->f
#define PROC_TABLE(f)                   cpu_vtable[0]->f
static inline void init_proc_vtable(const struct processor *p)
{
        unsigned int cpu = smp_processor_id();
        *cpu_vtable[cpu] = *p;
        WARN_ON_ONCE(cpu_vtable[cpu]->dcache_clean_area !=
                     cpu_vtable[0]->dcache_clean_area);
        WARN_ON_ONCE(cpu_vtable[cpu]->set_pte_ext !=
                     cpu_vtable[0]->set_pte_ext);
}
#else
#define PROC_VTABLE(f)                  processor.f
#define PROC_TABLE(f)                   processor.f
static inline void init_proc_vtable(const struct processor *p)
{
        processor = *p;
}
#endif

#define cpu_proc_init                   PROC_VTABLE(_proc_init)
#define cpu_check_bugs                  PROC_VTABLE(check_bugs)
#define cpu_proc_fin                    PROC_VTABLE(_proc_fin)
#define cpu_reset                       PROC_VTABLE(reset)
#define cpu_do_idle                     PROC_VTABLE(_do_idle)
#define cpu_dcache_clean_area           PROC_TABLE(dcache_clean_area)
#define cpu_set_pte_ext                 PROC_TABLE(set_pte_ext)
#define cpu_do_switch_mm                PROC_VTABLE(switch_mm)

/* These two are private to arch/arm/kernel/suspend.c */
#define cpu_do_suspend                  PROC_VTABLE(do_suspend)
#define cpu_do_resume                   PROC_VTABLE(do_resume)
#endif

extern void cpu_resume(void);

#ifdef CONFIG_MMU

#define cpu_switch_mm(pgd,mm) cpu_do_switch_mm(virt_to_phys(pgd),mm)

#ifdef CONFIG_ARM_LPAE

#define cpu_get_ttbr(nr)                                        \
        ({                                                      \
                u64 ttbr;                                       \
                __asm__("mrrc   p15, " #nr ", %Q0, %R0, c2"     \
                        : "=r" (ttbr));                         \
                ttbr;                                           \
        })

#define cpu_get_pgd()   \
        ({                                              \
                u64 pg = cpu_get_ttbr(0);               \
                pg &= ~(PTRS_PER_PGD*sizeof(pgd_t)-1);  \
                (pgd_t *)phys_to_virt(pg);              \
        })
#else
#define cpu_get_pgd()   \
        ({                                              \
                unsigned long pg;                       \
                __asm__("mrc    p15, 0, %0, c2, c0, 0"  \
                         : "=r" (pg) : : "cc");         \
                pg &= ~0x3fff;                          \
                (pgd_t *)phys_to_virt(pg);              \
        })
#endif

static inline unsigned int cpu_get_ttbcr(void)
{
        unsigned int ttbcr;
        asm("mrc p15, 0, %0, c2, c0, 2" : "=r" (ttbcr));
        return ttbcr;
}

static inline void cpu_set_ttbcr(unsigned int ttbcr)
{
        asm volatile("mcr p15, 0, %0, c2, c0, 2" : : "r" (ttbcr) : "memory");
}

#else   /*!CONFIG_MMU */

#define cpu_switch_mm(pgd,mm)   { }

#endif

#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* __ASM_PROCFNS_H */