u-boot-brain/arch/arm/mach-zynq/timer.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

110 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2017 Weidmüller Interface GmbH & Co. KG
* Stefan Herbrechtsmeier <stefan.herbrechtsmeier@weidmueller.com>
*
* Copyright (C) 2012 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2011-2017 Xilinx, Inc. All rights reserved.
*
* (C) Copyright 2008
* Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
*
* (C) Copyright 2004
* Philippe Robin, ARM Ltd. <philippe.robin@arm.com>
*
* (C) Copyright 2002-2004
* Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
*
* (C) Copyright 2003
* Texas Instruments <www.ti.com>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Alex Zuepke <azu@sysgo.de>
*/
#include <clk.h>
#include <common.h>
#include <div64.h>
#include <dm.h>
#include <asm/io.h>
#include <asm/arch/hardware.h>
#include <asm/arch/clk.h>
DECLARE_GLOBAL_DATA_PTR;
struct scu_timer {
u32 load; /* Timer Load Register */
u32 counter; /* Timer Counter Register */
u32 control; /* Timer Control Register */
};
static struct scu_timer *timer_base =
(struct scu_timer *)ZYNQ_SCUTIMER_BASEADDR;
#define SCUTIMER_CONTROL_PRESCALER_MASK 0x0000FF00 /* Prescaler */
#define SCUTIMER_CONTROL_PRESCALER_SHIFT 8
#define SCUTIMER_CONTROL_AUTO_RELOAD_MASK 0x00000002 /* Auto-reload */
#define SCUTIMER_CONTROL_ENABLE_MASK 0x00000001 /* Timer enable */
#define TIMER_LOAD_VAL 0xFFFFFFFF
#define TIMER_PRESCALE 255
int timer_init(void)
{
const u32 emask = SCUTIMER_CONTROL_AUTO_RELOAD_MASK |
(TIMER_PRESCALE << SCUTIMER_CONTROL_PRESCALER_SHIFT) |
SCUTIMER_CONTROL_ENABLE_MASK;
struct udevice *dev;
struct clk clk;
int ret;
ret = uclass_get_device_by_driver(UCLASS_CLK,
DM_GET_DRIVER(zynq_clk), &dev);
if (ret)
return ret;
clk.id = cpu_6or4x_clk;
ret = clk_request(dev, &clk);
if (ret < 0)
return ret;
gd->cpu_clk = clk_get_rate(&clk);
clk_free(&clk);
gd->arch.timer_rate_hz = (gd->cpu_clk / 2) / (TIMER_PRESCALE + 1);
/* Load the timer counter register */
writel(0xFFFFFFFF, &timer_base->load);
/*
* Start the A9Timer device
* Enable Auto reload mode, Clear prescaler control bits
* Set prescaler value, Enable the decrementer
*/
clrsetbits_le32(&timer_base->control, SCUTIMER_CONTROL_PRESCALER_MASK,
emask);
/* Reset time */
gd->arch.lastinc = readl(&timer_base->counter) /
(gd->arch.timer_rate_hz / CONFIG_SYS_HZ);
gd->arch.tbl = 0;
return 0;
}
/*
* This function is derived from PowerPC code (timebase clock frequency).
* On ARM it returns the number of timer ticks per second.
*/
ulong get_tbclk(void)
{
return gd->arch.timer_rate_hz;
}