drivers/timer/gxp-timer.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * GXP timer driver
   4  *
   5  * (C) Copyright 2022 Hewlett Packard Enterprise Development LP.
   6  * Author: Nick Hawkins <nick.hawkins@hpe.com>
   7  * Author: Jean-Marie Verdun <verdun@hpe.com>
   8  */
   9
  10 #include <clk.h>
  11 #include <dm.h>
  12 #include <timer.h>
  13 #include <asm/io.h>
  14
  15 #define USTIMELO        0x18
  16 #define USTIMEHI        0x1C
  17
  18 struct gxp_timer_priv {
  19         void __iomem *base;
  20 };
  21
  22 static u64 gxp_timer_get_count(struct udevice *dev)
  23 {
  24         struct gxp_timer_priv *priv = dev_get_priv(dev);
  25         u64 val;
  26
  27         val = readl(priv->base + USTIMEHI);
  28         val = (val << 32) | readl(priv->base + USTIMELO);
  29
  30         return val;
  31 }
  32
  33 static int gxp_timer_probe(struct udevice *dev)
  34 {
  35         struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
  36         struct gxp_timer_priv *priv = dev_get_priv(dev);
  37
  38         priv->base = dev_read_addr_ptr(dev);
  39         if (!priv->base)
  40                 return -ENOENT;
  41
  42         uc_priv->clock_rate = 1000000;
  43
  44         return 0;
  45 }
  46
  47 static const struct timer_ops gxp_timer_ops = {
  48         .get_count = gxp_timer_get_count,
  49 };
  50
  51 static const struct udevice_id gxp_timer_ids[] = {
  52         { .compatible = "hpe,gxp-timer" },
  53         {}
  54 };
  55
  56 U_BOOT_DRIVER(gxp_timer) = {
  57         .name = "gxp-timer",
  58         .id = UCLASS_TIMER,
  59         .of_match = gxp_timer_ids,
  60         .priv_auto = sizeof(struct gxp_timer_priv),
  61         .probe = gxp_timer_probe,
  62         .ops = &gxp_timer_ops,
  63         .flags = DM_FLAG_PRE_RELOC,
  64 };