LXR uboot/drivers/timer/andes_plmt

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2019, Rick Chen <rick@andestech.com>
   4 * Copyright (C) 2020, Sean Anderson <seanga2@gmail.com>
   5 *
   6 * U-Boot syscon driver for Andes's Platform Level Machine Timer (PLMT).
   7 * The PLMT block holds memory-mapped mtime register
   8 * associated with timer tick.
   9 */
  10
  11#include <common.h>
  12#include <dm.h>
  13#include <timer.h>
  14#include <asm/io.h>
  15#include <dm/device-internal.h>
  16#include <linux/err.h>
  17
  18/* mtime register */
  19#define MTIME_REG(base)                 ((ulong)(base))
  20
  21static u64 notrace andes_plmt_get_count(struct udevice *dev)
  22{
  23        return readq((void __iomem *)MTIME_REG(dev_get_priv(dev)));
  24}
  25
  26#if CONFIG_IS_ENABLED(RISCV_MMODE) && IS_ENABLED(CONFIG_TIMER_EARLY)
  27/**
  28 * timer_early_get_rate() - Get the timer rate before driver model
  29 */
  30unsigned long notrace timer_early_get_rate(void)
  31{
  32        return RISCV_MMODE_TIMER_FREQ;
  33}
  34
  35/**
  36 * timer_early_get_count() - Get the timer count before driver model
  37 *
  38 */
  39u64 notrace timer_early_get_count(void)
  40{
  41        return readq((void __iomem *)MTIME_REG(RISCV_MMODE_TIMERBASE));
  42}
  43#endif
  44
  45static const struct timer_ops andes_plmt_ops = {
  46        .get_count = andes_plmt_get_count,
  47};
  48
  49static int andes_plmt_probe(struct udevice *dev)
  50{
  51        dev_set_priv(dev, dev_read_addr_ptr(dev));
  52        if (!dev_get_priv(dev))
  53                return -EINVAL;
  54
  55        return timer_timebase_fallback(dev);
  56}
  57
  58static const struct udevice_id andes_plmt_ids[] = {
  59        { .compatible = "riscv,plmt0" },
  60        { }
  61};
  62
  63U_BOOT_DRIVER(andes_plmt) = {
  64        .name           = "andes_plmt",
  65        .id             = UCLASS_TIMER,
  66        .of_match       = andes_plmt_ids,
  67        .ops            = &andes_plmt_ops,
  68        .probe          = andes_plmt_probe,
  69        .flags          = DM_FLAG_PRE_RELOC,
  70};
  71