LXR uboot/drivers/timer/sti-timer.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
   4 * Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics.
   5 */
   6
   7#include <common.h>
   8#include <dm.h>
   9#include <fdtdec.h>
  10#include <timer.h>
  11
  12#include <asm/io.h>
  13#include <asm/arch-armv7/globaltimer.h>
  14
  15DECLARE_GLOBAL_DATA_PTR;
  16
  17struct sti_timer_priv {
  18        struct globaltimer *global_timer;
  19};
  20
  21static int sti_timer_get_count(struct udevice *dev, u64 *count)
  22{
  23        struct sti_timer_priv *priv = dev_get_priv(dev);
  24        struct globaltimer *global_timer = priv->global_timer;
  25        u32 low, high;
  26        u64 timer;
  27        u32 old = readl(&global_timer->cnt_h);
  28
  29        while (1) {
  30                low = readl(&global_timer->cnt_l);
  31                high = readl(&global_timer->cnt_h);
  32                if (old == high)
  33                        break;
  34                else
  35                        old = high;
  36        }
  37        timer = high;
  38        *count = (u64)((timer << 32) | low);
  39
  40        return 0;
  41}
  42
  43static int sti_timer_probe(struct udevice *dev)
  44{
  45        struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
  46        struct sti_timer_priv *priv = dev_get_priv(dev);
  47        fdt_addr_t addr;
  48
  49        uc_priv->clock_rate = CONFIG_SYS_HZ_CLOCK;
  50
  51        /* get arm global timer base address */
  52        addr = fdtdec_get_addr(gd->fdt_blob, dev_of_offset(dev), "reg");
  53        priv->global_timer = (struct globaltimer *)addr;
  54
  55        /* init timer */
  56        writel(0x01, &priv->global_timer->ctl);
  57
  58        return 0;
  59}
  60
  61static const struct timer_ops sti_timer_ops = {
  62        .get_count = sti_timer_get_count,
  63};
  64
  65static const struct udevice_id sti_timer_ids[] = {
  66        { .compatible = "arm,cortex-a9-global-timer" },
  67        {}
  68};
  69
  70U_BOOT_DRIVER(sti_timer) = {
  71        .name = "sti_timer",
  72        .id = UCLASS_TIMER,
  73        .of_match = sti_timer_ids,
  74        .priv_auto_alloc_size = sizeof(struct sti_timer_priv),
  75        .probe = sti_timer_probe,
  76        .ops = &sti_timer_ops,
  77};
  78