Git Repo - u-boot.git/blame_incremental - drivers/timer/timer-uclass.c

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Commit	Line	Data
	1	/*
	2	* Copyright (C) 2015 Thomas Chou <[email protected]>
	3	*
	4	* SPDX-License-Identifier: GPL-2.0+
	5	*/
	6
	7	#include <common.h>
	8	#include <dm.h>
	9	#include <dm/lists.h>
	10	#include <dm/device-internal.h>
	11	#include <clk.h>
	12	#include <errno.h>
	13	#include <timer.h>
	14
	15	DECLARE_GLOBAL_DATA_PTR;
	16
	17	/*
	18	* Implement a timer uclass to work with lib/time.c. The timer is usually
	19	* a 32/64 bits free-running up counter. The get_rate() method is used to get
	20	* the input clock frequency of the timer. The get_count() method is used
	21	* to get the current 64 bits count value. If the hardware is counting down,
	22	* the value should be inversed inside the method. There may be no real
	23	* tick, and no timer interrupt.
	24	*/
	25
	26	int notrace timer_get_count(struct udevice dev, u64 count)
	27	{
	28	const struct timer_ops *ops = device_get_ops(dev);
	29
	30	if (!ops->get_count)
	31	return -ENOSYS;
	32
	33	return ops->get_count(dev, count);
	34	}
	35
	36	unsigned long notrace timer_get_rate(struct udevice *dev)
	37	{
	38	struct timer_dev_priv *uc_priv = dev->uclass_priv;
	39
	40	return uc_priv->clock_rate;
	41	}
	42
	43	static int timer_pre_probe(struct udevice *dev)
	44	{
	45	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
	46	struct clk timer_clk;
	47	int err;
	48	ulong ret;
	49
	50	err = clk_get_by_index(dev, 0, &timer_clk);
	51	if (!err) {
	52	ret = clk_get_rate(&timer_clk);
	53	if (IS_ERR_VALUE(ret))
	54	return ret;
	55	uc_priv->clock_rate = ret;
	56	} else
	57	uc_priv->clock_rate = fdtdec_get_int(gd->fdt_blob,
	58	dev_of_offset(dev), "clock-frequency", 0);
	59
	60	return 0;
	61	}
	62
	63	static int timer_post_probe(struct udevice *dev)
	64	{
	65	struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
	66
	67	if (!uc_priv->clock_rate)
	68	return -EINVAL;
	69
	70	return 0;
	71	}
	72
	73	u64 timer_conv_64(u32 count)
	74	{
	75	/* increment tbh if tbl has rolled over */
	76	if (count < gd->timebase_l)
	77	gd->timebase_h++;
	78	gd->timebase_l = count;
	79	return ((u64)gd->timebase_h << 32) \| gd->timebase_l;
	80	}
	81
	82	int notrace dm_timer_init(void)
	83	{
	84	const void *blob = gd->fdt_blob;
	85	struct udevice *dev = NULL;
	86	int node;
	87	int ret;
	88
	89	if (gd->timer)
	90	return 0;
	91
	92	/* Check for a chosen timer to be used for tick */
	93	node = fdtdec_get_chosen_node(blob, "tick-timer");
	94	if (node < 0) {
	95	/* No chosen timer, trying first available timer */
	96	ret = uclass_first_device_err(UCLASS_TIMER, &dev);
	97	if (ret)
	98	return ret;
	99	} else {
	100	if (uclass_get_device_by_of_offset(UCLASS_TIMER, node, &dev)) {
	101	/*
	102	* If the timer is not marked to be bound before
	103	* relocation, bind it anyway.
	104	*/
	105	if (node > 0 &&
	106	!lists_bind_fdt(gd->dm_root, offset_to_ofnode(node),
	107	&dev)) {
	108	ret = device_probe(dev);
	109	if (ret)
	110	return ret;
	111	}
	112	}
	113	}
	114
	115	if (dev) {
	116	gd->timer = dev;
	117	return 0;
	118	}
	119
	120	return -ENODEV;
	121	}
	122
	123	UCLASS_DRIVER(timer) = {
	124	.id = UCLASS_TIMER,
	125	.name = "timer",
	126	.pre_probe = timer_pre_probe,
	127	.flags = DM_UC_FLAG_SEQ_ALIAS,
	128	.post_probe = timer_post_probe,
	129	.per_device_auto_alloc_size = sizeof(struct timer_dev_priv),
	130	};