arch/microblaze/cpu/timer.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * (C) Copyright 2007 Michal Simek
   4  *
   5  * Michal  SIMEK <monstr@monstr.eu>
   6  */
   7
   8 #include <common.h>
   9 #include <fdtdec.h>
  10 #include <init.h>
  11 #include <log.h>
  12 #include <time.h>
  13 #include <asm/microblaze_timer.h>
  14 #include <asm/microblaze_intc.h>
  15
  16 DECLARE_GLOBAL_DATA_PTR;
  17
  18 volatile int timestamp = 0;
  19 microblaze_timer_t *tmr;
  20
  21 ulong get_timer (ulong base)
  22 {
  23         if (tmr)
  24                 return timestamp - base;
  25         return timestamp++ - base;
  26 }
  27
  28 void __udelay(unsigned long usec)
  29 {
  30         u32 i;
  31
  32         if (tmr) {
  33                 i = get_timer(0);
  34                 while ((get_timer(0) - i) < (usec / 1000))
  35                         ;
  36         }
  37 }
  38
  39 #ifndef CONFIG_SPL_BUILD
  40 static void timer_isr(void *arg)
  41 {
  42         timestamp++;
  43         tmr->control = tmr->control | TIMER_INTERRUPT;
  44 }
  45
  46 int timer_init (void)
  47 {
  48         int irq = -1;
  49         u32 preload = 0;
  50         u32 ret = 0;
  51         const void *blob = gd->fdt_blob;
  52         int node = 0;
  53         u32 cell[2];
  54
  55         debug("TIMER: Initialization\n");
  56
  57         /* Do not init before relocation */
  58         if (!(gd->flags & GD_FLG_RELOC))
  59                 return 0;
  60
  61         node = fdt_node_offset_by_compatible(blob, node,
  62                                 "xlnx,xps-timer-1.00.a");
  63         if (node != -1) {
  64                 fdt_addr_t base = fdtdec_get_addr(blob, node, "reg");
  65                 if (base == FDT_ADDR_T_NONE)
  66                         return -1;
  67
  68                 debug("TIMER: Base addr %lx\n", base);
  69                 tmr = (microblaze_timer_t *)base;
  70
  71                 ret = fdtdec_get_int_array(blob, node, "interrupts",
  72                                             cell, ARRAY_SIZE(cell));
  73                 if (ret)
  74                         return ret;
  75
  76                 irq = cell[0];
  77                 debug("TIMER: IRQ %x\n", irq);
  78
  79                 preload = fdtdec_get_int(blob, node, "clock-frequency", 0);
  80                 preload /= CONFIG_SYS_HZ;
  81         } else {
  82                 return node;
  83         }
  84
  85         if (tmr && preload && irq >= 0) {
  86                 tmr->loadreg = preload;
  87                 tmr->control = TIMER_INTERRUPT | TIMER_RESET;
  88                 tmr->control = TIMER_ENABLE | TIMER_ENABLE_INTR |\
  89                                         TIMER_RELOAD | TIMER_DOWN_COUNT;
  90                 timestamp = 0;
  91                 ret = install_interrupt_handler (irq, timer_isr, (void *)tmr);
  92                 if (ret)
  93                         tmr = NULL;
  94         }
  95         /* No problem if timer is not found/initialized */
  96         return 0;
  97 }
  98 #else
  99 int timer_init(void)
 100 {
 101         return 0;
 102 }
 103 #endif
 104
 105 /*
 106  * This function is derived from PowerPC code (read timebase as long long).
 107  * On Microblaze it just returns the timer value.
 108  */
 109 unsigned long long get_ticks(void)
 110 {
 111         return get_timer(0);
 112 }
 113
 114 /*
 115  * This function is derived from PowerPC code (timebase clock frequency).
 116  * On Microblaze it returns the number of timer ticks per second.
 117  */
 118 ulong get_tbclk(void)
 119 {
 120         return CONFIG_SYS_HZ;
 121 }