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linux-stable/drivers/clocksource/timer-tegra186.c
Rob Herring 6303d0693f clocksource: Explicitly include correct DT includes 
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it was merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Link: https://lore.kernel.org/r/20230714174409.4053843-1-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
2023-08-28 13:30:57 -05:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2019-2020 NVIDIA Corporation. All rights reserved.
*/
#include <linux/clocksource.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/watchdog.h>
/* shared registers */
#define TKETSC0 0x000
#define TKETSC1 0x004
#define TKEUSEC 0x008
#define TKEOSC 0x00c
#define TKEIE(x) (0x100 + ((x) * 4))
#define TKEIE_WDT_MASK(x, y) ((y) << (16 + 4 * (x)))
/* timer registers */
#define TMRCR 0x000
#define TMRCR_ENABLE BIT(31)
#define TMRCR_PERIODIC BIT(30)
#define TMRCR_PTV(x) ((x) & 0x0fffffff)
#define TMRSR 0x004
#define TMRSR_INTR_CLR BIT(30)
#define TMRCSSR 0x008
#define TMRCSSR_SRC_USEC (0 << 0)
/* watchdog registers */
#define WDTCR 0x000
#define WDTCR_SYSTEM_POR_RESET_ENABLE BIT(16)
#define WDTCR_SYSTEM_DEBUG_RESET_ENABLE BIT(15)
#define WDTCR_REMOTE_INT_ENABLE BIT(14)
#define WDTCR_LOCAL_FIQ_ENABLE BIT(13)
#define WDTCR_LOCAL_INT_ENABLE BIT(12)
#define WDTCR_PERIOD_MASK (0xff << 4)
#define WDTCR_PERIOD(x) (((x) & 0xff) << 4)
#define WDTCR_TIMER_SOURCE_MASK 0xf
#define WDTCR_TIMER_SOURCE(x) ((x) & 0xf)
#define WDTCMDR 0x008
#define WDTCMDR_DISABLE_COUNTER BIT(1)
#define WDTCMDR_START_COUNTER BIT(0)
#define WDTUR 0x00c
#define WDTUR_UNLOCK_PATTERN 0x0000c45a
struct tegra186_timer_soc {
unsigned int num_timers;
unsigned int num_wdts;
};
struct tegra186_tmr {
struct tegra186_timer *parent;
void __iomem *regs;
unsigned int index;
unsigned int hwirq;
};
struct tegra186_wdt {
struct watchdog_device base;
void __iomem *regs;
unsigned int index;
bool locked;
struct tegra186_tmr *tmr;
};
static inline struct tegra186_wdt *to_tegra186_wdt(struct watchdog_device *wdd)
{
return container_of(wdd, struct tegra186_wdt, base);
}
struct tegra186_timer {
const struct tegra186_timer_soc *soc;
struct device *dev;
void __iomem *regs;
struct tegra186_wdt *wdt;
struct clocksource usec;
struct clocksource tsc;
struct clocksource osc;
};
static void tmr_writel(struct tegra186_tmr *tmr, u32 value, unsigned int offset)
{
writel_relaxed(value, tmr->regs + offset);
}
static void wdt_writel(struct tegra186_wdt *wdt, u32 value, unsigned int offset)
{
writel_relaxed(value, wdt->regs + offset);
}
static u32 wdt_readl(struct tegra186_wdt *wdt, unsigned int offset)
{
return readl_relaxed(wdt->regs + offset);
}
static struct tegra186_tmr *tegra186_tmr_create(struct tegra186_timer *tegra,
unsigned int index)
{
unsigned int offset = 0x10000 + index * 0x10000;
struct tegra186_tmr *tmr;
tmr = devm_kzalloc(tegra->dev, sizeof(*tmr), GFP_KERNEL);
if (!tmr)
return ERR_PTR(-ENOMEM);
tmr->parent = tegra;
tmr->regs = tegra->regs + offset;
tmr->index = index;
tmr->hwirq = 0;
return tmr;
}
static const struct watchdog_info tegra186_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
.identity = "NVIDIA Tegra186 WDT",
};
static void tegra186_wdt_disable(struct tegra186_wdt *wdt)
{
/* unlock and disable the watchdog */
wdt_writel(wdt, WDTUR_UNLOCK_PATTERN, WDTUR);
wdt_writel(wdt, WDTCMDR_DISABLE_COUNTER, WDTCMDR);
/* disable timer */
tmr_writel(wdt->tmr, 0, TMRCR);
}
static void tegra186_wdt_enable(struct tegra186_wdt *wdt)
{
struct tegra186_timer *tegra = wdt->tmr->parent;
u32 value;
/* unmask hardware IRQ, this may have been lost across powergate */
value = TKEIE_WDT_MASK(wdt->index, 1);
writel(value, tegra->regs + TKEIE(wdt->tmr->hwirq));
/* clear interrupt */
tmr_writel(wdt->tmr, TMRSR_INTR_CLR, TMRSR);
/* select microsecond source */
tmr_writel(wdt->tmr, TMRCSSR_SRC_USEC, TMRCSSR);
/* configure timer (system reset happens on the fifth expiration) */
value = TMRCR_PTV(wdt->base.timeout * USEC_PER_SEC / 5) |
TMRCR_PERIODIC | TMRCR_ENABLE;
tmr_writel(wdt->tmr, value, TMRCR);
if (!wdt->locked) {
value = wdt_readl(wdt, WDTCR);
/* select the proper timer source */
value &= ~WDTCR_TIMER_SOURCE_MASK;
value |= WDTCR_TIMER_SOURCE(wdt->tmr->index);
/* single timer period since that's already configured */
value &= ~WDTCR_PERIOD_MASK;
value |= WDTCR_PERIOD(1);
/* enable local interrupt for WDT petting */
value |= WDTCR_LOCAL_INT_ENABLE;
/* enable local FIQ and remote interrupt for debug dump */
if (0)
value |= WDTCR_REMOTE_INT_ENABLE |
WDTCR_LOCAL_FIQ_ENABLE;
/* enable system debug reset (doesn't properly reboot) */
if (0)
value |= WDTCR_SYSTEM_DEBUG_RESET_ENABLE;
/* enable system POR reset */
value |= WDTCR_SYSTEM_POR_RESET_ENABLE;
wdt_writel(wdt, value, WDTCR);
}
wdt_writel(wdt, WDTCMDR_START_COUNTER, WDTCMDR);
}
static int tegra186_wdt_start(struct watchdog_device *wdd)
{
struct tegra186_wdt *wdt = to_tegra186_wdt(wdd);
tegra186_wdt_enable(wdt);
return 0;
}
static int tegra186_wdt_stop(struct watchdog_device *wdd)
{
struct tegra186_wdt *wdt = to_tegra186_wdt(wdd);
tegra186_wdt_disable(wdt);
return 0;
}
static int tegra186_wdt_ping(struct watchdog_device *wdd)
{
struct tegra186_wdt *wdt = to_tegra186_wdt(wdd);
tegra186_wdt_disable(wdt);
tegra186_wdt_enable(wdt);
return 0;
}
static int tegra186_wdt_set_timeout(struct watchdog_device *wdd,
unsigned int timeout)
{
struct tegra186_wdt *wdt = to_tegra186_wdt(wdd);
if (watchdog_active(&wdt->base))
tegra186_wdt_disable(wdt);
wdt->base.timeout = timeout;
if (watchdog_active(&wdt->base))
tegra186_wdt_enable(wdt);
return 0;
}
static const struct watchdog_ops tegra186_wdt_ops = {
.owner = THIS_MODULE,
.start = tegra186_wdt_start,
.stop = tegra186_wdt_stop,
.ping = tegra186_wdt_ping,
.set_timeout = tegra186_wdt_set_timeout,
};
static struct tegra186_wdt *tegra186_wdt_create(struct tegra186_timer *tegra,
unsigned int index)
{
unsigned int offset = 0x10000, source;
struct tegra186_wdt *wdt;
u32 value;
int err;
offset += tegra->soc->num_timers * 0x10000 + index * 0x10000;
wdt = devm_kzalloc(tegra->dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return ERR_PTR(-ENOMEM);
wdt->regs = tegra->regs + offset;
wdt->index = index;
/* read the watchdog configuration since it might be locked down */
value = wdt_readl(wdt, WDTCR);
if (value & WDTCR_LOCAL_INT_ENABLE)
wdt->locked = true;
source = value & WDTCR_TIMER_SOURCE_MASK;
wdt->tmr = tegra186_tmr_create(tegra, source);
if (IS_ERR(wdt->tmr))
return ERR_CAST(wdt->tmr);
wdt->base.info = &tegra186_wdt_info;
wdt->base.ops = &tegra186_wdt_ops;
wdt->base.min_timeout = 1;
wdt->base.max_timeout = 255;
wdt->base.parent = tegra->dev;
err = watchdog_init_timeout(&wdt->base, 5, tegra->dev);
if (err < 0) {
dev_err(tegra->dev, "failed to initialize timeout: %d\n", err);
return ERR_PTR(err);
}
err = devm_watchdog_register_device(tegra->dev, &wdt->base);
if (err < 0) {
dev_err(tegra->dev, "failed to register WDT: %d\n", err);
return ERR_PTR(err);
}
return wdt;
}
static u64 tegra186_timer_tsc_read(struct clocksource *cs)
{
struct tegra186_timer *tegra = container_of(cs, struct tegra186_timer,
tsc);
u32 hi, lo, ss;
hi = readl_relaxed(tegra->regs + TKETSC1);
/*
* The 56-bit value of the TSC is spread across two registers that are
* not synchronized. In order to read them atomically, ensure that the
* high 24 bits match before and after reading the low 32 bits.
*/
do {
/* snapshot the high 24 bits */
ss = hi;
lo = readl_relaxed(tegra->regs + TKETSC0);
hi = readl_relaxed(tegra->regs + TKETSC1);
} while (hi != ss);
return (u64)hi << 32 | lo;
}
static int tegra186_timer_tsc_init(struct tegra186_timer *tegra)
{
tegra->tsc.name = "tsc";
tegra->tsc.rating = 300;
tegra->tsc.read = tegra186_timer_tsc_read;
tegra->tsc.mask = CLOCKSOURCE_MASK(56);
tegra->tsc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
return clocksource_register_hz(&tegra->tsc, 31250000);
}
static u64 tegra186_timer_osc_read(struct clocksource *cs)
{
struct tegra186_timer *tegra = container_of(cs, struct tegra186_timer,
osc);
return readl_relaxed(tegra->regs + TKEOSC);
}
static int tegra186_timer_osc_init(struct tegra186_timer *tegra)
{
tegra->osc.name = "osc";
tegra->osc.rating = 300;
tegra->osc.read = tegra186_timer_osc_read;
tegra->osc.mask = CLOCKSOURCE_MASK(32);
tegra->osc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
return clocksource_register_hz(&tegra->osc, 38400000);
}
static u64 tegra186_timer_usec_read(struct clocksource *cs)
{
struct tegra186_timer *tegra = container_of(cs, struct tegra186_timer,
usec);
return readl_relaxed(tegra->regs + TKEUSEC);
}
static int tegra186_timer_usec_init(struct tegra186_timer *tegra)
{
tegra->usec.name = "usec";
tegra->usec.rating = 300;
tegra->usec.read = tegra186_timer_usec_read;
tegra->usec.mask = CLOCKSOURCE_MASK(32);
tegra->usec.flags = CLOCK_SOURCE_IS_CONTINUOUS;
return clocksource_register_hz(&tegra->usec, USEC_PER_SEC);
}
static irqreturn_t tegra186_timer_irq(int irq, void *data)
{
struct tegra186_timer *tegra = data;
if (watchdog_active(&tegra->wdt->base)) {
tegra186_wdt_disable(tegra->wdt);
tegra186_wdt_enable(tegra->wdt);
}
return IRQ_HANDLED;
}
static int tegra186_timer_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct tegra186_timer *tegra;
unsigned int irq;
int err;
tegra = devm_kzalloc(dev, sizeof(*tegra), GFP_KERNEL);
if (!tegra)
return -ENOMEM;
tegra->soc = of_device_get_match_data(dev);
dev_set_drvdata(dev, tegra);
tegra->dev = dev;
tegra->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(tegra->regs))
return PTR_ERR(tegra->regs);
err = platform_get_irq(pdev, 0);
if (err < 0)
return err;
irq = err;
/* create a watchdog using a preconfigured timer */
tegra->wdt = tegra186_wdt_create(tegra, 0);
if (IS_ERR(tegra->wdt)) {
err = PTR_ERR(tegra->wdt);
dev_err(dev, "failed to create WDT: %d\n", err);
return err;
}
err = tegra186_timer_tsc_init(tegra);
if (err < 0) {
dev_err(dev, "failed to register TSC counter: %d\n", err);
return err;
}
err = tegra186_timer_osc_init(tegra);
if (err < 0) {
dev_err(dev, "failed to register OSC counter: %d\n", err);
goto unregister_tsc;
}
err = tegra186_timer_usec_init(tegra);
if (err < 0) {
dev_err(dev, "failed to register USEC counter: %d\n", err);
goto unregister_osc;
}
err = devm_request_irq(dev, irq, tegra186_timer_irq, 0,
"tegra186-timer", tegra);
if (err < 0) {
dev_err(dev, "failed to request IRQ#%u: %d\n", irq, err);
goto unregister_usec;
}
return 0;
unregister_usec:
clocksource_unregister(&tegra->usec);
unregister_osc:
clocksource_unregister(&tegra->osc);
unregister_tsc:
clocksource_unregister(&tegra->tsc);
return err;
}
static void tegra186_timer_remove(struct platform_device *pdev)
{
struct tegra186_timer *tegra = platform_get_drvdata(pdev);
clocksource_unregister(&tegra->usec);
clocksource_unregister(&tegra->osc);
clocksource_unregister(&tegra->tsc);
}
static int __maybe_unused tegra186_timer_suspend(struct device *dev)
{
struct tegra186_timer *tegra = dev_get_drvdata(dev);
if (watchdog_active(&tegra->wdt->base))
tegra186_wdt_disable(tegra->wdt);
return 0;
}
static int __maybe_unused tegra186_timer_resume(struct device *dev)
{
struct tegra186_timer *tegra = dev_get_drvdata(dev);
if (watchdog_active(&tegra->wdt->base))
tegra186_wdt_enable(tegra->wdt);
return 0;
}
static SIMPLE_DEV_PM_OPS(tegra186_timer_pm_ops, tegra186_timer_suspend,
tegra186_timer_resume);
static const struct tegra186_timer_soc tegra186_timer = {
.num_timers = 10,
.num_wdts = 3,
};
static const struct tegra186_timer_soc tegra234_timer = {
.num_timers = 16,
.num_wdts = 3,
};
static const struct of_device_id tegra186_timer_of_match[] = {
{ .compatible = "nvidia,tegra186-timer", .data = &tegra186_timer },
{ .compatible = "nvidia,tegra234-timer", .data = &tegra234_timer },
{ }
};
MODULE_DEVICE_TABLE(of, tegra186_timer_of_match);
static struct platform_driver tegra186_wdt_driver = {
.driver = {
.name = "tegra186-timer",
.pm = &tegra186_timer_pm_ops,
.of_match_table = tegra186_timer_of_match,
},
.probe = tegra186_timer_probe,
.remove_new = tegra186_timer_remove,
};
module_platform_driver(tegra186_wdt_driver);
MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
MODULE_DESCRIPTION("NVIDIA Tegra186 timers driver");
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