u-boot/drivers/timer/arc_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

112 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2016 Synopsys, Inc. All rights reserved.
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <timer.h>
#include <asm/arcregs.h>
#include <asm/io.h>
DECLARE_GLOBAL_DATA_PTR;
#define NH_MODE (1 << 1)
/*
* ARC timer control registers are mapped to auxiliary address space.
* There are special ARC asm command to access that addresses.
* Therefore we use built-in functions to read from and write to timer
* control register.
*/
/* Driver private data. Contains timer id. Could be either 0 or 1. */
struct arc_timer_priv {
uint timer_id;
};
static int arc_timer_get_count(struct udevice *dev, u64 *count)
{
u32 val = 0;
struct arc_timer_priv *priv = dev_get_priv(dev);
switch (priv->timer_id) {
case 0:
val = read_aux_reg(ARC_AUX_TIMER0_CNT);
break;
case 1:
val = read_aux_reg(ARC_AUX_TIMER1_CNT);
break;
}
*count = timer_conv_64(val);
return 0;
}
static int arc_timer_probe(struct udevice *dev)
{
int id;
struct arc_timer_priv *priv = dev_get_priv(dev);
/* Get registers offset and size */
id = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev), "reg", -1);
if (id < 0)
return -EINVAL;
if (id > 1)
return -ENXIO;
priv->timer_id = (uint)id;
/*
* In ARC core there're special registers (Auxiliary or AUX) in its
* separate memory space that are used for accessing some hardware
* features of the core. They are not mapped in normal memory space
* and also always have the same location regardless core configuration.
* Thus to simplify understanding of the programming model we chose to
* access AUX regs of Timer0 and Timer1 separately instead of using
* offsets from some base address.
*/
switch (priv->timer_id) {
case 0:
/* Disable timer if CPU is halted */
write_aux_reg(ARC_AUX_TIMER0_CTRL, NH_MODE);
/* Set max value for counter/timer */
write_aux_reg(ARC_AUX_TIMER0_LIMIT, 0xffffffff);
/* Set initial count value and restart counter/timer */
write_aux_reg(ARC_AUX_TIMER0_CNT, 0);
break;
case 1:
/* Disable timer if CPU is halted */
write_aux_reg(ARC_AUX_TIMER1_CTRL, NH_MODE);
/* Set max value for counter/timer */
write_aux_reg(ARC_AUX_TIMER1_LIMIT, 0xffffffff);
/* Set initial count value and restart counter/timer */
write_aux_reg(ARC_AUX_TIMER1_CNT, 0);
break;
}
return 0;
}
static const struct timer_ops arc_timer_ops = {
.get_count = arc_timer_get_count,
};
static const struct udevice_id arc_timer_ids[] = {
{ .compatible = "snps,arc-timer" },
{}
};
U_BOOT_DRIVER(arc_timer) = {
.name = "arc_timer",
.id = UCLASS_TIMER,
.of_match = arc_timer_ids,
.probe = arc_timer_probe,
.ops = &arc_timer_ops,
.flags = DM_FLAG_PRE_RELOC,
.priv_auto_alloc_size = sizeof(struct arc_timer_priv),
};