drivers/timer/rockchip_timer.c

   1 /*
   2  * Copyright (C) 2017 Theobroma Systems Design und Consulting GmbH
   3  *
   4  * SPDX-License-Identifier: GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <dm.h>
   9 #include <dm/ofnode.h>
  10 #include <mapmem.h>
  11 #include <asm/arch/timer.h>
  12 #include <dt-structs.h>
  13 #include <timer.h>
  14 #include <asm/io.h>
  15
  16 DECLARE_GLOBAL_DATA_PTR;
  17
  18 #if CONFIG_IS_ENABLED(OF_PLATDATA)
  19 struct rockchip_timer_plat {
  20         struct dtd_rockchip_rk3368_timer dtd;
  21 };
  22 #endif
  23
  24 /* Driver private data. Contains timer id. Could be either 0 or 1. */
  25 struct rockchip_timer_priv {
  26         struct rk_timer *timer;
  27 };
  28
  29 static inline int64_t rockchip_timer_get_curr_value(struct rk_timer *timer)
  30 {
  31         uint64_t timebase_h, timebase_l;
  32         uint64_t cntr;
  33
  34         timebase_l = readl(&timer->timer_curr_value0);
  35         timebase_h = readl(&timer->timer_curr_value1);
  36
  37         cntr = timebase_h << 32 | timebase_l;
  38         return cntr;
  39 }
  40
  41 #if CONFIG_IS_ENABLED(BOOTSTAGE)
  42 ulong timer_get_boot_us(void)
  43 {
  44         uint64_t  ticks = 0;
  45         uint32_t  rate;
  46         uint64_t  us;
  47         int ret;
  48
  49         ret = dm_timer_init();
  50
  51         if (!ret) {
  52                 /* The timer is available */
  53                 rate = timer_get_rate(gd->timer);
  54                 timer_get_count(gd->timer, &ticks);
  55 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
  56         } else if (ret == -EAGAIN) {
  57                 /* We have been called so early that the DM is not ready,... */
  58                 ofnode node = offset_to_ofnode(-1);
  59                 struct rk_timer *timer = NULL;
  60
  61                 /*
  62                  * ... so we try to access the raw timer, if it is specified
  63                  * via the tick-timer property in /chosen.
  64                  */
  65                 node = ofnode_get_chosen_node("tick-timer");
  66                 if (!ofnode_valid(node)) {
  67                         debug("%s: no /chosen/tick-timer\n", __func__);
  68                         return 0;
  69                 }
  70
  71                 timer = (struct rk_timer *)ofnode_get_addr(node);
  72
  73                 /* This timer is down-counting */
  74                 ticks = ~0uLL - rockchip_timer_get_curr_value(timer);
  75                 if (ofnode_read_u32(node, "clock-frequency", &rate)) {
  76                         debug("%s: could not read clock-frequency\n", __func__);
  77                         return 0;
  78                 }
  79 #endif
  80         } else {
  81                 return 0;
  82         }
  83
  84         us = (ticks * 1000) / rate;
  85         return us;
  86 }
  87 #endif
  88
  89 static int rockchip_timer_get_count(struct udevice *dev, u64 *count)
  90 {
  91         struct rockchip_timer_priv *priv = dev_get_priv(dev);
  92         uint64_t cntr = rockchip_timer_get_curr_value(priv->timer);
  93
  94         /* timers are down-counting */
  95         *count = ~0ull - cntr;
  96         return 0;
  97 }
  98
  99 static int rockchip_clk_ofdata_to_platdata(struct udevice *dev)
 100 {
 101 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
 102         struct rockchip_timer_priv *priv = dev_get_priv(dev);
 103
 104         priv->timer = dev_read_addr_ptr(dev);
 105         if (!priv->timer)
 106                 return -ENOENT;
 107 #endif
 108
 109         return 0;
 110 }
 111
 112 static int rockchip_timer_start(struct udevice *dev)
 113 {
 114         struct rockchip_timer_priv *priv = dev_get_priv(dev);
 115         const uint64_t reload_val = ~0uLL;
 116         const uint32_t reload_val_l = reload_val & 0xffffffff;
 117         const uint32_t reload_val_h = reload_val >> 32;
 118
 119         /* don't reinit, if the timer is already running and set up */
 120         if ((readl(&priv->timer->timer_ctrl_reg) & 1) == 1 &&
 121             (readl(&priv->timer->timer_load_count0) == reload_val_l) &&
 122             (readl(&priv->timer->timer_load_count1) == reload_val_h))
 123                 return 0;
 124
 125         /* disable timer and reset all control */
 126         writel(0, &priv->timer->timer_ctrl_reg);
 127         /* write reload value */
 128         writel(reload_val_l, &priv->timer->timer_load_count0);
 129         writel(reload_val_h, &priv->timer->timer_load_count1);
 130         /* enable timer */
 131         writel(1, &priv->timer->timer_ctrl_reg);
 132
 133         return 0;
 134 }
 135
 136 static int rockchip_timer_probe(struct udevice *dev)
 137 {
 138 #if CONFIG_IS_ENABLED(OF_PLATDATA)
 139         struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
 140         struct rockchip_timer_priv *priv = dev_get_priv(dev);
 141         struct rockchip_timer_plat *plat = dev_get_platdata(dev);
 142
 143         priv->timer = map_sysmem(plat->dtd.reg[1], plat->dtd.reg[3]);
 144         uc_priv->clock_rate = plat->dtd.clock_frequency;
 145 #endif
 146
 147         return rockchip_timer_start(dev);
 148 }
 149
 150 static const struct timer_ops rockchip_timer_ops = {
 151         .get_count = rockchip_timer_get_count,
 152 };
 153
 154 static const struct udevice_id rockchip_timer_ids[] = {
 155         { .compatible = "rockchip,rk3368-timer" },
 156         {}
 157 };
 158
 159 U_BOOT_DRIVER(rockchip_rk3368_timer) = {
 160         .name   = "rockchip_rk3368_timer",
 161         .id     = UCLASS_TIMER,
 162         .of_match = rockchip_timer_ids,
 163         .probe = rockchip_timer_probe,
 164         .ops    = &rockchip_timer_ops,
 165         .flags = DM_FLAG_PRE_RELOC,
 166         .priv_auto_alloc_size = sizeof(struct rockchip_timer_priv),
 167 #if CONFIG_IS_ENABLED(OF_PLATDATA)
 168         .platdata_auto_alloc_size = sizeof(struct rockchip_timer_plat),
 169 #endif
 170         .ofdata_to_platdata = rockchip_clk_ofdata_to_platdata,
 171 };