root/arch/sparc/include/asm/timer_64.h

INCLUDED FROM

DEFINITIONS

1. get_tick

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /* timer.h: System timer definitions for sun5.
   3  *
   4  * Copyright (C) 1997, 2008 David S. Miller (davem@davemloft.net)
   5  */
   6 
   7 #ifndef _SPARC64_TIMER_H
   8 #define _SPARC64_TIMER_H
   9 
  10 #include <linux/types.h>
  11 #include <linux/init.h>
  12 
  13 /* The most frequently accessed fields should be first,
  14  * to fit into the same cacheline.
  15  */
  16 struct sparc64_tick_ops {
  17         unsigned long ticks_per_nsec_quotient;
  18         unsigned long offset;
  19         unsigned long long (*get_tick)(void);
  20         int (*add_compare)(unsigned long);
  21         unsigned long softint_mask;
  22         void (*disable_irq)(void);
  23 
  24         void (*init_tick)(void);
  25         unsigned long (*add_tick)(unsigned long);
  26         unsigned long (*get_frequency)(void);
  27         unsigned long frequency;
  28 
  29         char *name;
  30 };
  31 
  32 extern struct sparc64_tick_ops *tick_ops;
  33 
  34 unsigned long sparc64_get_clock_tick(unsigned int cpu);
  35 void setup_sparc64_timer(void);
  36 void __init time_init(void);
  37 
  38 #define TICK_PRIV_BIT           BIT(63)
  39 #define TICKCMP_IRQ_BIT         BIT(63)
  40 
  41 #define HBIRD_STICKCMP_ADDR     0x1fe0000f060UL
  42 #define HBIRD_STICK_ADDR        0x1fe0000f070UL
  43 
  44 #define GET_TICK_NINSTR         13
  45 struct get_tick_patch {
  46         unsigned int    addr;
  47         unsigned int    tick[GET_TICK_NINSTR];
  48         unsigned int    stick[GET_TICK_NINSTR];
  49 };
  50 
  51 extern struct get_tick_patch __get_tick_patch;
  52 extern struct get_tick_patch __get_tick_patch_end;
  53 
  54 static inline unsigned long get_tick(void)
  55 {
  56         unsigned long tick, tmp1, tmp2;
  57 
  58         __asm__ __volatile__(
  59         /* read hbtick 13 instructions */
  60         "661:\n"
  61         "       mov     0x1fe, %1\n"
  62         "       sllx    %1, 0x20, %1\n"
  63         "       sethi   %%hi(0xf000), %2\n"
  64         "       or      %2, 0x70, %2\n"
  65         "       or      %1, %2, %1\n"   /* %1 = HBIRD_STICK_ADDR */
  66         "       add     %1, 8, %2\n"
  67         "       ldxa    [%2]%3, %0\n"
  68         "       ldxa    [%1]%3, %1\n"
  69         "       ldxa    [%2]%3, %2\n"
  70         "       sub     %2, %0, %0\n"   /* don't modify %xcc */
  71         "       brnz,pn %0, 661b\n"     /* restart to save one register */
  72         "        sllx   %2, 32, %2\n"
  73         "       or      %2, %1, %0\n"
  74         /* Common/not patched code */
  75         "       sllx    %0, 1, %0\n"
  76         "       srlx    %0, 1, %0\n"    /* Clear TICK_PRIV_BIT */
  77         /* Beginning of patch section */
  78         "       .section .get_tick_patch, \"ax\"\n"
  79         "       .word   661b\n"
  80         /* read tick 2 instructions and 11 skipped */
  81         "       ba      1f\n"
  82         "        rd     %%tick, %0\n"
  83         "       .skip   4 * (%4 - 2)\n"
  84         "1:\n"
  85         /* read stick 2 instructions and 11 skipped */
  86         "       ba      1f\n"
  87         "        rd     %%asr24, %0\n"
  88         "       .skip   4 * (%4 - 2)\n"
  89         "1:\n"
  90         /* End of patch section */
  91         "       .previous\n"
  92         : "=&r" (tick), "=&r" (tmp1), "=&r" (tmp2)
  93         : "i" (ASI_PHYS_BYPASS_EC_E), "i" (GET_TICK_NINSTR));
  94 
  95         return tick;
  96 }
  97 
  98 #endif /* _SPARC64_TIMER_H */