linux/drivers/watchdog/orion_wdt.c
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 Version: GnuPG v2
 
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00

655 lines
17 KiB
C

/*
* drivers/watchdog/orion_wdt.c
*
* Watchdog driver for Orion/Kirkwood processors
*
* Author: Sylver Bruneau <sylver.bruneau@googlemail.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/of_device.h>
/* RSTOUT mask register physical address for Orion5x, Kirkwood and Dove */
#define ORION_RSTOUT_MASK_OFFSET 0x20108
/* Internal registers can be configured at any 1 MiB aligned address */
#define INTERNAL_REGS_MASK ~(SZ_1M - 1)
/*
* Watchdog timer block registers.
*/
#define TIMER_CTRL 0x0000
#define TIMER_A370_STATUS 0x04
#define WDT_MAX_CYCLE_COUNT 0xffffffff
#define WDT_A370_RATIO_MASK(v) ((v) << 16)
#define WDT_A370_RATIO_SHIFT 5
#define WDT_A370_RATIO (1 << WDT_A370_RATIO_SHIFT)
#define WDT_AXP_FIXED_ENABLE_BIT BIT(10)
#define WDT_A370_EXPIRED BIT(31)
static bool nowayout = WATCHDOG_NOWAYOUT;
static int heartbeat = -1; /* module parameter (seconds) */
struct orion_watchdog;
struct orion_watchdog_data {
int wdt_counter_offset;
int wdt_enable_bit;
int rstout_enable_bit;
int rstout_mask_bit;
int (*clock_init)(struct platform_device *,
struct orion_watchdog *);
int (*enabled)(struct orion_watchdog *);
int (*start)(struct watchdog_device *);
int (*stop)(struct watchdog_device *);
};
struct orion_watchdog {
struct watchdog_device wdt;
void __iomem *reg;
void __iomem *rstout;
void __iomem *rstout_mask;
unsigned long clk_rate;
struct clk *clk;
const struct orion_watchdog_data *data;
};
static int orion_wdt_clock_init(struct platform_device *pdev,
struct orion_watchdog *dev)
{
int ret;
dev->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(dev->clk))
return PTR_ERR(dev->clk);
ret = clk_prepare_enable(dev->clk);
if (ret) {
clk_put(dev->clk);
return ret;
}
dev->clk_rate = clk_get_rate(dev->clk);
return 0;
}
static int armada370_wdt_clock_init(struct platform_device *pdev,
struct orion_watchdog *dev)
{
int ret;
dev->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(dev->clk))
return PTR_ERR(dev->clk);
ret = clk_prepare_enable(dev->clk);
if (ret) {
clk_put(dev->clk);
return ret;
}
/* Setup watchdog input clock */
atomic_io_modify(dev->reg + TIMER_CTRL,
WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT),
WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT));
dev->clk_rate = clk_get_rate(dev->clk) / WDT_A370_RATIO;
return 0;
}
static int armada375_wdt_clock_init(struct platform_device *pdev,
struct orion_watchdog *dev)
{
int ret;
dev->clk = of_clk_get_by_name(pdev->dev.of_node, "fixed");
if (!IS_ERR(dev->clk)) {
ret = clk_prepare_enable(dev->clk);
if (ret) {
clk_put(dev->clk);
return ret;
}
atomic_io_modify(dev->reg + TIMER_CTRL,
WDT_AXP_FIXED_ENABLE_BIT,
WDT_AXP_FIXED_ENABLE_BIT);
dev->clk_rate = clk_get_rate(dev->clk);
return 0;
}
/* Mandatory fallback for proper devicetree backward compatibility */
dev->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(dev->clk))
return PTR_ERR(dev->clk);
ret = clk_prepare_enable(dev->clk);
if (ret) {
clk_put(dev->clk);
return ret;
}
atomic_io_modify(dev->reg + TIMER_CTRL,
WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT),
WDT_A370_RATIO_MASK(WDT_A370_RATIO_SHIFT));
dev->clk_rate = clk_get_rate(dev->clk) / WDT_A370_RATIO;
return 0;
}
static int armadaxp_wdt_clock_init(struct platform_device *pdev,
struct orion_watchdog *dev)
{
int ret;
dev->clk = of_clk_get_by_name(pdev->dev.of_node, "fixed");
if (IS_ERR(dev->clk))
return PTR_ERR(dev->clk);
ret = clk_prepare_enable(dev->clk);
if (ret) {
clk_put(dev->clk);
return ret;
}
/* Enable the fixed watchdog clock input */
atomic_io_modify(dev->reg + TIMER_CTRL,
WDT_AXP_FIXED_ENABLE_BIT,
WDT_AXP_FIXED_ENABLE_BIT);
dev->clk_rate = clk_get_rate(dev->clk);
return 0;
}
static int orion_wdt_ping(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
/* Reload watchdog duration */
writel(dev->clk_rate * wdt_dev->timeout,
dev->reg + dev->data->wdt_counter_offset);
return 0;
}
static int armada375_start(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
u32 reg;
/* Set watchdog duration */
writel(dev->clk_rate * wdt_dev->timeout,
dev->reg + dev->data->wdt_counter_offset);
/* Clear the watchdog expiration bit */
atomic_io_modify(dev->reg + TIMER_A370_STATUS, WDT_A370_EXPIRED, 0);
/* Enable watchdog timer */
atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit,
dev->data->wdt_enable_bit);
/* Enable reset on watchdog */
reg = readl(dev->rstout);
reg |= dev->data->rstout_enable_bit;
writel(reg, dev->rstout);
atomic_io_modify(dev->rstout_mask, dev->data->rstout_mask_bit, 0);
return 0;
}
static int armada370_start(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
u32 reg;
/* Set watchdog duration */
writel(dev->clk_rate * wdt_dev->timeout,
dev->reg + dev->data->wdt_counter_offset);
/* Clear the watchdog expiration bit */
atomic_io_modify(dev->reg + TIMER_A370_STATUS, WDT_A370_EXPIRED, 0);
/* Enable watchdog timer */
atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit,
dev->data->wdt_enable_bit);
/* Enable reset on watchdog */
reg = readl(dev->rstout);
reg |= dev->data->rstout_enable_bit;
writel(reg, dev->rstout);
return 0;
}
static int orion_start(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
/* Set watchdog duration */
writel(dev->clk_rate * wdt_dev->timeout,
dev->reg + dev->data->wdt_counter_offset);
/* Enable watchdog timer */
atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit,
dev->data->wdt_enable_bit);
/* Enable reset on watchdog */
atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit,
dev->data->rstout_enable_bit);
return 0;
}
static int orion_wdt_start(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
/* There are some per-SoC quirks to handle */
return dev->data->start(wdt_dev);
}
static int orion_stop(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
/* Disable reset on watchdog */
atomic_io_modify(dev->rstout, dev->data->rstout_enable_bit, 0);
/* Disable watchdog timer */
atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit, 0);
return 0;
}
static int armada375_stop(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
u32 reg;
/* Disable reset on watchdog */
atomic_io_modify(dev->rstout_mask, dev->data->rstout_mask_bit,
dev->data->rstout_mask_bit);
reg = readl(dev->rstout);
reg &= ~dev->data->rstout_enable_bit;
writel(reg, dev->rstout);
/* Disable watchdog timer */
atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit, 0);
return 0;
}
static int armada370_stop(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
u32 reg;
/* Disable reset on watchdog */
reg = readl(dev->rstout);
reg &= ~dev->data->rstout_enable_bit;
writel(reg, dev->rstout);
/* Disable watchdog timer */
atomic_io_modify(dev->reg + TIMER_CTRL, dev->data->wdt_enable_bit, 0);
return 0;
}
static int orion_wdt_stop(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
return dev->data->stop(wdt_dev);
}
static int orion_enabled(struct orion_watchdog *dev)
{
bool enabled, running;
enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
return enabled && running;
}
static int armada375_enabled(struct orion_watchdog *dev)
{
bool masked, enabled, running;
masked = readl(dev->rstout_mask) & dev->data->rstout_mask_bit;
enabled = readl(dev->rstout) & dev->data->rstout_enable_bit;
running = readl(dev->reg + TIMER_CTRL) & dev->data->wdt_enable_bit;
return !masked && enabled && running;
}
static int orion_wdt_enabled(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
return dev->data->enabled(dev);
}
static unsigned int orion_wdt_get_timeleft(struct watchdog_device *wdt_dev)
{
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
return readl(dev->reg + dev->data->wdt_counter_offset) / dev->clk_rate;
}
static int orion_wdt_set_timeout(struct watchdog_device *wdt_dev,
unsigned int timeout)
{
wdt_dev->timeout = timeout;
return 0;
}
static const struct watchdog_info orion_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "Orion Watchdog",
};
static const struct watchdog_ops orion_wdt_ops = {
.owner = THIS_MODULE,
.start = orion_wdt_start,
.stop = orion_wdt_stop,
.ping = orion_wdt_ping,
.set_timeout = orion_wdt_set_timeout,
.get_timeleft = orion_wdt_get_timeleft,
};
static irqreturn_t orion_wdt_irq(int irq, void *devid)
{
panic("Watchdog Timeout");
return IRQ_HANDLED;
}
/*
* The original devicetree binding for this driver specified only
* one memory resource, so in order to keep DT backwards compatibility
* we try to fallback to a hardcoded register address, if the resource
* is missing from the devicetree.
*/
static void __iomem *orion_wdt_ioremap_rstout(struct platform_device *pdev,
phys_addr_t internal_regs)
{
struct resource *res;
phys_addr_t rstout;
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (res)
return devm_ioremap(&pdev->dev, res->start,
resource_size(res));
rstout = internal_regs + ORION_RSTOUT_MASK_OFFSET;
WARN(1, FW_BUG "falling back to harcoded RSTOUT reg %pa\n", &rstout);
return devm_ioremap(&pdev->dev, rstout, 0x4);
}
static const struct orion_watchdog_data orion_data = {
.rstout_enable_bit = BIT(1),
.wdt_enable_bit = BIT(4),
.wdt_counter_offset = 0x24,
.clock_init = orion_wdt_clock_init,
.enabled = orion_enabled,
.start = orion_start,
.stop = orion_stop,
};
static const struct orion_watchdog_data armada370_data = {
.rstout_enable_bit = BIT(8),
.wdt_enable_bit = BIT(8),
.wdt_counter_offset = 0x34,
.clock_init = armada370_wdt_clock_init,
.enabled = orion_enabled,
.start = armada370_start,
.stop = armada370_stop,
};
static const struct orion_watchdog_data armadaxp_data = {
.rstout_enable_bit = BIT(8),
.wdt_enable_bit = BIT(8),
.wdt_counter_offset = 0x34,
.clock_init = armadaxp_wdt_clock_init,
.enabled = orion_enabled,
.start = armada370_start,
.stop = armada370_stop,
};
static const struct orion_watchdog_data armada375_data = {
.rstout_enable_bit = BIT(8),
.rstout_mask_bit = BIT(10),
.wdt_enable_bit = BIT(8),
.wdt_counter_offset = 0x34,
.clock_init = armada375_wdt_clock_init,
.enabled = armada375_enabled,
.start = armada375_start,
.stop = armada375_stop,
};
static const struct orion_watchdog_data armada380_data = {
.rstout_enable_bit = BIT(8),
.rstout_mask_bit = BIT(10),
.wdt_enable_bit = BIT(8),
.wdt_counter_offset = 0x34,
.clock_init = armadaxp_wdt_clock_init,
.enabled = armada375_enabled,
.start = armada375_start,
.stop = armada375_stop,
};
static const struct of_device_id orion_wdt_of_match_table[] = {
{
.compatible = "marvell,orion-wdt",
.data = &orion_data,
},
{
.compatible = "marvell,armada-370-wdt",
.data = &armada370_data,
},
{
.compatible = "marvell,armada-xp-wdt",
.data = &armadaxp_data,
},
{
.compatible = "marvell,armada-375-wdt",
.data = &armada375_data,
},
{
.compatible = "marvell,armada-380-wdt",
.data = &armada380_data,
},
{},
};
MODULE_DEVICE_TABLE(of, orion_wdt_of_match_table);
static int orion_wdt_get_regs(struct platform_device *pdev,
struct orion_watchdog *dev)
{
struct device_node *node = pdev->dev.of_node;
struct resource *res;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
dev->reg = devm_ioremap(&pdev->dev, res->start,
resource_size(res));
if (!dev->reg)
return -ENOMEM;
/* Each supported compatible has some RSTOUT register quirk */
if (of_device_is_compatible(node, "marvell,orion-wdt")) {
dev->rstout = orion_wdt_ioremap_rstout(pdev, res->start &
INTERNAL_REGS_MASK);
if (!dev->rstout)
return -ENODEV;
} else if (of_device_is_compatible(node, "marvell,armada-370-wdt") ||
of_device_is_compatible(node, "marvell,armada-xp-wdt")) {
/* Dedicated RSTOUT register, can be requested. */
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
dev->rstout = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(dev->rstout))
return PTR_ERR(dev->rstout);
} else if (of_device_is_compatible(node, "marvell,armada-375-wdt") ||
of_device_is_compatible(node, "marvell,armada-380-wdt")) {
/* Dedicated RSTOUT register, can be requested. */
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
dev->rstout = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(dev->rstout))
return PTR_ERR(dev->rstout);
res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
if (!res)
return -ENODEV;
dev->rstout_mask = devm_ioremap(&pdev->dev, res->start,
resource_size(res));
if (!dev->rstout_mask)
return -ENOMEM;
} else {
return -ENODEV;
}
return 0;
}
static int orion_wdt_probe(struct platform_device *pdev)
{
struct orion_watchdog *dev;
const struct of_device_id *match;
unsigned int wdt_max_duration; /* (seconds) */
int ret, irq;
dev = devm_kzalloc(&pdev->dev, sizeof(struct orion_watchdog),
GFP_KERNEL);
if (!dev)
return -ENOMEM;
match = of_match_device(orion_wdt_of_match_table, &pdev->dev);
if (!match)
/* Default legacy match */
match = &orion_wdt_of_match_table[0];
dev->wdt.info = &orion_wdt_info;
dev->wdt.ops = &orion_wdt_ops;
dev->wdt.min_timeout = 1;
dev->data = match->data;
ret = orion_wdt_get_regs(pdev, dev);
if (ret)
return ret;
ret = dev->data->clock_init(pdev, dev);
if (ret) {
dev_err(&pdev->dev, "cannot initialize clock\n");
return ret;
}
wdt_max_duration = WDT_MAX_CYCLE_COUNT / dev->clk_rate;
dev->wdt.timeout = wdt_max_duration;
dev->wdt.max_timeout = wdt_max_duration;
watchdog_init_timeout(&dev->wdt, heartbeat, &pdev->dev);
platform_set_drvdata(pdev, &dev->wdt);
watchdog_set_drvdata(&dev->wdt, dev);
/*
* Let's make sure the watchdog is fully stopped, unless it's
* explicitly enabled. This may be the case if the module was
* removed and re-insterted, or if the bootloader explicitly
* set a running watchdog before booting the kernel.
*/
if (!orion_wdt_enabled(&dev->wdt))
orion_wdt_stop(&dev->wdt);
/* Request the IRQ only after the watchdog is disabled */
irq = platform_get_irq(pdev, 0);
if (irq > 0) {
/*
* Not all supported platforms specify an interrupt for the
* watchdog, so let's make it optional.
*/
ret = devm_request_irq(&pdev->dev, irq, orion_wdt_irq, 0,
pdev->name, dev);
if (ret < 0) {
dev_err(&pdev->dev, "failed to request IRQ\n");
goto disable_clk;
}
}
watchdog_set_nowayout(&dev->wdt, nowayout);
ret = watchdog_register_device(&dev->wdt);
if (ret)
goto disable_clk;
pr_info("Initial timeout %d sec%s\n",
dev->wdt.timeout, nowayout ? ", nowayout" : "");
return 0;
disable_clk:
clk_disable_unprepare(dev->clk);
clk_put(dev->clk);
return ret;
}
static int orion_wdt_remove(struct platform_device *pdev)
{
struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
struct orion_watchdog *dev = watchdog_get_drvdata(wdt_dev);
watchdog_unregister_device(wdt_dev);
clk_disable_unprepare(dev->clk);
clk_put(dev->clk);
return 0;
}
static void orion_wdt_shutdown(struct platform_device *pdev)
{
struct watchdog_device *wdt_dev = platform_get_drvdata(pdev);
orion_wdt_stop(wdt_dev);
}
static struct platform_driver orion_wdt_driver = {
.probe = orion_wdt_probe,
.remove = orion_wdt_remove,
.shutdown = orion_wdt_shutdown,
.driver = {
.name = "orion_wdt",
.of_match_table = orion_wdt_of_match_table,
},
};
module_platform_driver(orion_wdt_driver);
MODULE_AUTHOR("Sylver Bruneau <sylver.bruneau@googlemail.com>");
MODULE_DESCRIPTION("Orion Processor Watchdog");
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Initial watchdog heartbeat in seconds");
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:orion_wdt");