drivers/timer/cadence-ttc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2018 Xilinx, Inc. (Michal Simek)
   4  */
   5
   6 #include <common.h>
   7 #include <dm.h>
   8 #include <errno.h>
   9 #include <timer.h>
  10 #include <asm/io.h>
  11
  12 #define CNT_CNTRL_RESET         BIT(4)
  13
  14 struct cadence_ttc_regs {
  15         u32 clk_cntrl1; /* 0x0 - Clock Control 1 */
  16         u32 clk_cntrl2; /* 0x4 - Clock Control 2 */
  17         u32 clk_cntrl3; /* 0x8 - Clock Control 3 */
  18         u32 counter_cntrl1; /* 0xC - Counter Control 1 */
  19         u32 counter_cntrl2; /* 0x10 - Counter Control 2 */
  20         u32 counter_cntrl3; /* 0x14 - Counter Control 3 */
  21         u32 counter_val1; /* 0x18 - Counter Control 1 */
  22         u32 counter_val2; /* 0x1C - Counter Control 2 */
  23         u32 counter_val3; /* 0x20 - Counter Control 3 */
  24         u32 reserved[15];
  25         u32 interrupt_enable1; /* 0x60 - Interrupt Enable 1 */
  26         u32 interrupt_enable2; /* 0x64 - Interrupt Enable 2 */
  27         u32 interrupt_enable3; /* 0x68 - Interrupt Enable 3 */
  28 };
  29
  30 struct cadence_ttc_priv {
  31         struct cadence_ttc_regs *regs;
  32 };
  33
  34 #if CONFIG_IS_ENABLED(BOOTSTAGE)
  35 ulong timer_get_boot_us(void)
  36 {
  37         u64 ticks = 0;
  38         u32 rate = 1;
  39         u64 us;
  40         int ret;
  41
  42         ret = dm_timer_init();
  43         if (!ret) {
  44                 /* The timer is available */
  45                 rate = timer_get_rate(gd->timer);
  46                 timer_get_count(gd->timer, &ticks);
  47         } else {
  48                 return 0;
  49         }
  50
  51         us = (ticks * 1000) / rate;
  52         return us;
  53 }
  54 #endif
  55
  56 static int cadence_ttc_get_count(struct udevice *dev, u64 *count)
  57 {
  58         struct cadence_ttc_priv *priv = dev_get_priv(dev);
  59
  60         *count = readl(&priv->regs->counter_val1);
  61
  62         return 0;
  63 }
  64
  65 static int cadence_ttc_probe(struct udevice *dev)
  66 {
  67         struct cadence_ttc_priv *priv = dev_get_priv(dev);
  68
  69         /* Disable interrupts for sure */
  70         writel(0, &priv->regs->interrupt_enable1);
  71         writel(0, &priv->regs->interrupt_enable2);
  72         writel(0, &priv->regs->interrupt_enable3);
  73
  74         /* Make sure that clocks are configured properly without prescaller */
  75         writel(0, &priv->regs->clk_cntrl1);
  76         writel(0, &priv->regs->clk_cntrl2);
  77         writel(0, &priv->regs->clk_cntrl3);
  78
  79         /* Reset and enable this counter */
  80         writel(CNT_CNTRL_RESET, &priv->regs->counter_cntrl1);
  81
  82         return 0;
  83 }
  84
  85 static int cadence_ttc_ofdata_to_platdata(struct udevice *dev)
  86 {
  87         struct cadence_ttc_priv *priv = dev_get_priv(dev);
  88
  89         priv->regs = map_physmem(dev_read_addr(dev),
  90                                  sizeof(struct cadence_ttc_regs), MAP_NOCACHE);
  91         if (IS_ERR(priv->regs))
  92                 return PTR_ERR(priv->regs);
  93
  94         return 0;
  95 }
  96
  97 static const struct timer_ops cadence_ttc_ops = {
  98         .get_count = cadence_ttc_get_count,
  99 };
 100
 101 static const struct udevice_id cadence_ttc_ids[] = {
 102         { .compatible = "cdns,ttc" },
 103         {}
 104 };
 105
 106 U_BOOT_DRIVER(cadence_ttc) = {
 107         .name = "cadence_ttc",
 108         .id = UCLASS_TIMER,
 109         .of_match = cadence_ttc_ids,
 110         .ofdata_to_platdata = cadence_ttc_ofdata_to_platdata,
 111         .priv_auto_alloc_size = sizeof(struct cadence_ttc_priv),
 112         .probe = cadence_ttc_probe,
 113         .ops = &cadence_ttc_ops,
 114 };