Git Repo - u-boot.git/blame_incremental - drivers/timer/altera

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Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0+
	2	/*
	3	* (C) Copyright 2000-2002
	4	* Wolfgang Denk, DENX Software Engineering, [email protected].
	5	*
	6	* (C) Copyright 2004, Psyent Corporation <www.psyent.com>
	7	* Scott McNutt <[email protected]>
	8	*/
	9
	10	#include <common.h>
	11	#include <dm.h>
	12	#include <errno.h>
	13	#include <timer.h>
	14	#include <asm/io.h>
	15	#include <linux/bitops.h>
	16
	17	/* control register */
	18	#define ALTERA_TIMER_CONT BIT(1) /* Continuous mode */
	19	#define ALTERA_TIMER_START BIT(2) /* Start timer */
	20	#define ALTERA_TIMER_STOP BIT(3) /* Stop timer */
	21
	22	struct altera_timer_regs {
	23	u32 status; /* Timer status reg */
	24	u32 control; /* Timer control reg */
	25	u32 periodl; /* Timeout period low */
	26	u32 periodh; /* Timeout period high */
	27	u32 snapl; /* Snapshot low */
	28	u32 snaph; /* Snapshot high */
	29	};
	30
	31	struct altera_timer_platdata {
	32	struct altera_timer_regs *regs;
	33	};
	34
	35	static u64 altera_timer_get_count(struct udevice *dev)
	36	{
	37	struct altera_timer_platdata *plat = dev->platdata;
	38	struct altera_timer_regs *const regs = plat->regs;
	39	u32 val;
	40
	41	/* Trigger update */
	42	writel(0x0, &regs->snapl);
	43
	44	/* Read timer value */
	45	val = readl(&regs->snapl) & 0xffff;
	46	val \|= (readl(&regs->snaph) & 0xffff) << 16;
	47	return timer_conv_64(~val);
	48	}
	49
	50	static int altera_timer_probe(struct udevice *dev)
	51	{
	52	struct altera_timer_platdata *plat = dev->platdata;
	53	struct altera_timer_regs *const regs = plat->regs;
	54
	55	writel(0, &regs->status);
	56	writel(0, &regs->control);
	57	writel(ALTERA_TIMER_STOP, &regs->control);
	58
	59	writel(0xffff, &regs->periodl);
	60	writel(0xffff, &regs->periodh);
	61	writel(ALTERA_TIMER_CONT \| ALTERA_TIMER_START, &regs->control);
	62
	63	return 0;
	64	}
	65
	66	static int altera_timer_ofdata_to_platdata(struct udevice *dev)
	67	{
	68	struct altera_timer_platdata *plat = dev_get_platdata(dev);
	69
	70	plat->regs = map_physmem(dev_read_addr(dev),
	71	sizeof(struct altera_timer_regs),
	72	MAP_NOCACHE);
	73
	74	return 0;
	75	}
	76
	77	static const struct timer_ops altera_timer_ops = {
	78	.get_count = altera_timer_get_count,
	79	};
	80
	81	static const struct udevice_id altera_timer_ids[] = {
	82	{ .compatible = "altr,timer-1.0" },
	83	{}
	84	};
	85
	86	U_BOOT_DRIVER(altera_timer) = {
	87	.name = "altera_timer",
	88	.id = UCLASS_TIMER,
	89	.of_match = altera_timer_ids,
	90	.ofdata_to_platdata = altera_timer_ofdata_to_platdata,
	91	.platdata_auto_alloc_size = sizeof(struct altera_timer_platdata),
	92	.probe = altera_timer_probe,
	93	.ops = &altera_timer_ops,
	94	};