mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-23 11:33:32 +00:00
0e6956cc7d
Simplify the code a bit by using dev_read_addr_ptr() instead of dev_read_addr(). This avoids having to cast explicitly to the struct nomadik_mtu_regs. Signed-off-by: Stephan Gerhold <stephan@gerhold.net> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
110 lines
2.8 KiB
C
110 lines
2.8 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Copyright (C) 2019 Stephan Gerhold <stephan@gerhold.net>
|
|
*
|
|
* Based on arch/arm/cpu/armv7/u8500/timer.c:
|
|
* Copyright (C) 2010 Linaro Limited
|
|
* John Rigby <john.rigby@linaro.org>
|
|
*
|
|
* Based on Linux kernel source and internal ST-Ericsson U-Boot source:
|
|
* Copyright (C) 2009 Alessandro Rubini
|
|
* Copyright (C) 2010 ST-Ericsson
|
|
* Copyright (C) 2010 Linus Walleij for ST-Ericsson
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <dm.h>
|
|
#include <timer.h>
|
|
#include <asm/io.h>
|
|
#include <linux/bitops.h>
|
|
|
|
#define MTU_NUM_TIMERS 4
|
|
|
|
/* The timers */
|
|
struct nomadik_mtu_timer_regs {
|
|
u32 lr; /* Load register */
|
|
u32 cv; /* Current value */
|
|
u32 cr; /* Control register */
|
|
u32 bglr; /* Background load register */
|
|
};
|
|
|
|
/* The MTU that contains the timers */
|
|
struct nomadik_mtu_regs {
|
|
u32 imsc; /* Interrupt mask set/clear */
|
|
u32 ris; /* Raw interrupt status */
|
|
u32 mis; /* Masked interrupt status */
|
|
u32 icr; /* Interrupt clear register */
|
|
|
|
struct nomadik_mtu_timer_regs timers[MTU_NUM_TIMERS];
|
|
};
|
|
|
|
/* Bits for the control register */
|
|
#define MTU_CR_ONESHOT BIT(0) /* if 0 = wraps reloading from BGLR */
|
|
#define MTU_CR_32BITS BIT(1) /* if 0 = 16-bit counter */
|
|
|
|
#define MTU_CR_PRESCALE_SHIFT 2
|
|
#define MTU_CR_PRESCALE_1 (0 << MTU_CR_PRESCALE_SHIFT)
|
|
#define MTU_CR_PRESCALE_16 (1 << MTU_CR_PRESCALE_SHIFT)
|
|
#define MTU_CR_PRESCALE_256 (2 << MTU_CR_PRESCALE_SHIFT)
|
|
|
|
#define MTU_CR_PERIODIC BIT(6) /* if 0 = free-running */
|
|
#define MTU_CR_ENABLE BIT(7)
|
|
|
|
struct nomadik_mtu_priv {
|
|
struct nomadik_mtu_timer_regs *timer;
|
|
};
|
|
|
|
static u64 nomadik_mtu_get_count(struct udevice *dev)
|
|
{
|
|
struct nomadik_mtu_priv *priv = dev_get_priv(dev);
|
|
|
|
/* Decrementing counter: invert the value */
|
|
return timer_conv_64(~readl(&priv->timer->cv));
|
|
}
|
|
|
|
static int nomadik_mtu_probe(struct udevice *dev)
|
|
{
|
|
struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
|
|
struct nomadik_mtu_priv *priv = dev_get_priv(dev);
|
|
struct nomadik_mtu_regs *mtu;
|
|
u32 prescale;
|
|
|
|
mtu = dev_read_addr_ptr(dev);
|
|
if (!mtu)
|
|
return -EINVAL;
|
|
priv->timer = mtu->timers; /* Use first timer */
|
|
|
|
if (!uc_priv->clock_rate)
|
|
return -EINVAL;
|
|
|
|
/* Use divide-by-16 counter if tick rate is more than 32 MHz */
|
|
if (uc_priv->clock_rate > 32000000) {
|
|
uc_priv->clock_rate /= 16;
|
|
prescale = MTU_CR_PRESCALE_16;
|
|
} else {
|
|
prescale = MTU_CR_PRESCALE_1;
|
|
}
|
|
|
|
/* Configure a free-running, auto-wrap counter with selected prescale */
|
|
writel(MTU_CR_ENABLE | prescale | MTU_CR_32BITS, &priv->timer->cr);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct timer_ops nomadik_mtu_ops = {
|
|
.get_count = nomadik_mtu_get_count,
|
|
};
|
|
|
|
static const struct udevice_id nomadik_mtu_ids[] = {
|
|
{ .compatible = "st,nomadik-mtu" },
|
|
{}
|
|
};
|
|
|
|
U_BOOT_DRIVER(nomadik_mtu) = {
|
|
.name = "nomadik_mtu",
|
|
.id = UCLASS_TIMER,
|
|
.of_match = nomadik_mtu_ids,
|
|
.priv_auto = sizeof(struct nomadik_mtu_priv),
|
|
.probe = nomadik_mtu_probe,
|
|
.ops = &nomadik_mtu_ops,
|
|
};
|