drivers/timer/mtk_timer.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * MediaTek timer driver
   4  *
   5  * Copyright (C) 2018 MediaTek Inc.
   6  * Author: Ryder Lee <[email protected]>
   7  */
   8
   9 #include <clk.h>
  10 #include <common.h>
  11 #include <dm.h>
  12 #include <timer.h>
  13 #include <asm/io.h>
  14 #include <linux/bitops.h>
  15
  16 #define MTK_GPT4_CTRL   0x40
  17 #define MTK_GPT4_CLK    0x44
  18 #define MTK_GPT4_CNT    0x48
  19
  20 #define GPT4_ENABLE     BIT(0)
  21 #define GPT4_CLEAR      BIT(1)
  22 #define GPT4_FREERUN    GENMASK(5, 4)
  23 #define GPT4_CLK_SYS    0x0
  24 #define GPT4_CLK_DIV1   0x0
  25
  26 struct mtk_timer_priv {
  27         void __iomem *base;
  28 };
  29
  30 static u64 mtk_timer_get_count(struct udevice *dev)
  31 {
  32         struct mtk_timer_priv *priv = dev_get_priv(dev);
  33         u32 val = readl(priv->base + MTK_GPT4_CNT);
  34
  35         return timer_conv_64(val);
  36 }
  37
  38 static int mtk_timer_probe(struct udevice *dev)
  39 {
  40         struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
  41         struct mtk_timer_priv *priv = dev_get_priv(dev);
  42         struct clk clk, parent;
  43         int ret;
  44
  45         priv->base = dev_read_addr_ptr(dev);
  46         if (!priv->base)
  47                 return -ENOENT;
  48
  49         ret = clk_get_by_index(dev, 0, &clk);
  50         if (ret)
  51                 return ret;
  52
  53         ret = clk_get_by_index(dev, 1, &parent);
  54         if (!ret) {
  55                 ret = clk_set_parent(&clk, &parent);
  56                 if (ret)
  57                         return ret;
  58         }
  59
  60         uc_priv->clock_rate = clk_get_rate(&clk);
  61         if (!uc_priv->clock_rate)
  62                 return -EINVAL;
  63
  64         return 0;
  65 }
  66
  67 static const struct timer_ops mtk_timer_ops = {
  68         .get_count = mtk_timer_get_count,
  69 };
  70
  71 static const struct udevice_id mtk_timer_ids[] = {
  72         { .compatible = "mediatek,timer" },
  73         { .compatible = "mediatek,mt6577-timer" },
  74         { }
  75 };
  76
  77 U_BOOT_DRIVER(mtk_timer) = {
  78         .name = "mtk_timer",
  79         .id = UCLASS_TIMER,
  80         .of_match = mtk_timer_ids,
  81         .priv_auto      = sizeof(struct mtk_timer_priv),
  82         .probe = mtk_timer_probe,
  83         .ops = &mtk_timer_ops,
  84         .flags = DM_FLAG_PRE_RELOC,
  85 };