drivers/timer/sandbox_timer.c

   1 /*
   2  * Copyright (C) 2015 Thomas Chou <thomas@wytron.com.tw>
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <dm.h>
   9 #include <errno.h>
  10 #include <timer.h>
  11 #include <os.h>
  12
  13 #define SANDBOX_TIMER_RATE      1000000
  14
  15 /* system timer offset in ms */
  16 static unsigned long sandbox_timer_offset;
  17
  18 void sandbox_timer_add_offset(unsigned long offset)
  19 {
  20         sandbox_timer_offset += offset;
  21 }
  22
  23 u64 notrace timer_early_get_count(void)
  24 {
  25         return os_get_nsec() / 1000 + sandbox_timer_offset * 1000;
  26 }
  27
  28 unsigned long notrace timer_early_get_rate(void)
  29 {
  30         return SANDBOX_TIMER_RATE;
  31 }
  32
  33 static notrace int sandbox_timer_get_count(struct udevice *dev, u64 *count)
  34 {
  35         *count = timer_early_get_count();
  36
  37         return 0;
  38 }
  39
  40 static int sandbox_timer_probe(struct udevice *dev)
  41 {
  42         struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
  43
  44         if (!uc_priv->clock_rate)
  45                 uc_priv->clock_rate = SANDBOX_TIMER_RATE;
  46
  47         return 0;
  48 }
  49
  50 static const struct timer_ops sandbox_timer_ops = {
  51         .get_count = sandbox_timer_get_count,
  52 };
  53
  54 static const struct udevice_id sandbox_timer_ids[] = {
  55         { .compatible = "sandbox,timer" },
  56         { }
  57 };
  58
  59 U_BOOT_DRIVER(sandbox_timer) = {
  60         .name   = "sandbox_timer",
  61         .id     = UCLASS_TIMER,
  62         .of_match = sandbox_timer_ids,
  63         .probe = sandbox_timer_probe,
  64         .ops    = &sandbox_timer_ops,
  65         .flags = DM_FLAG_PRE_RELOC,
  66 };
  67
  68 /* This is here in case we don't have a device tree */
  69 U_BOOT_DEVICE(sandbox_timer_non_fdt) = {
  70         .name = "sandbox_timer",
  71 };