/* SPDX-License-Identifier: GPL-2.0 */
/* timer.h: System timer definitions for sun5.
 *
 * Copyright (C) 1997, 2008 David S. Miller (davem@davemloft.net)
 */

#ifndef _SPARC64_TIMER_H
#define _SPARC64_TIMER_H

#include <uapi/asm/asi.h>
#include <linux/types.h>
#include <linux/init.h>

/* The most frequently accessed fields should be first,
 * to fit into the same cacheline.
 */
struct sparc64_tick_ops {
        unsigned long ticks_per_nsec_quotient;
        unsigned long offset;
        unsigned long long (*get_tick)(void);
        int (*add_compare)(unsigned long);
        unsigned long softint_mask;
        void (*disable_irq)(void);

        void (*init_tick)(void);
        unsigned long (*add_tick)(unsigned long);
        unsigned long (*get_frequency)(void);
        unsigned long frequency;

        char *name;
};

extern struct sparc64_tick_ops *tick_ops;

unsigned long sparc64_get_clock_tick(unsigned int cpu);
void setup_sparc64_timer(void);

#define TICK_PRIV_BIT           BIT(63)
#define TICKCMP_IRQ_BIT         BIT(63)

#define HBIRD_STICKCMP_ADDR     0x1fe0000f060UL
#define HBIRD_STICK_ADDR        0x1fe0000f070UL

#define GET_TICK_NINSTR         13
struct get_tick_patch {
        unsigned int    addr;
        unsigned int    tick[GET_TICK_NINSTR];
        unsigned int    stick[GET_TICK_NINSTR];
};

extern struct get_tick_patch __get_tick_patch;
extern struct get_tick_patch __get_tick_patch_end;

static inline unsigned long get_tick(void)
{
        unsigned long tick, tmp1, tmp2;

        __asm__ __volatile__(
        /* read hbtick 13 instructions */
        "661:\n"
        "       mov     0x1fe, %1\n"
        "       sllx    %1, 0x20, %1\n"
        "       sethi   %%hi(0xf000), %2\n"
        "       or      %2, 0x70, %2\n"
        "       or      %1, %2, %1\n"   /* %1 = HBIRD_STICK_ADDR */
        "       add     %1, 8, %2\n"
        "       ldxa    [%2]%3, %0\n"
        "       ldxa    [%1]%3, %1\n"
        "       ldxa    [%2]%3, %2\n"
        "       sub     %2, %0, %0\n"   /* don't modify %xcc */
        "       brnz,pn %0, 661b\n"     /* restart to save one register */
        "        sllx   %2, 32, %2\n"
        "       or      %2, %1, %0\n"
        /* Common/not patched code */
        "       sllx    %0, 1, %0\n"
        "       srlx    %0, 1, %0\n"    /* Clear TICK_PRIV_BIT */
        /* Beginning of patch section */
        "       .section .get_tick_patch, \"ax\"\n"
        "       .word   661b\n"
        /* read tick 2 instructions and 11 skipped */
        "       ba      1f\n"
        "        rd     %%tick, %0\n"
        "       .skip   4 * (%4 - 2)\n"
        "1:\n"
        /* read stick 2 instructions and 11 skipped */
        "       ba      1f\n"
        "        rd     %%asr24, %0\n"
        "       .skip   4 * (%4 - 2)\n"
        "1:\n"
        /* End of patch section */
        "       .previous\n"
        : "=&r" (tick), "=&r" (tmp1), "=&r" (tmp2)
        : "i" (ASI_PHYS_BYPASS_EC_E), "i" (GET_TICK_NINSTR));

        return tick;
}

#endif /* _SPARC64_TIMER_H */