* [PATCH v5 1/2] dt-bindings: watchdog: Add Spreadtrum watchdog documentation
@ 2017-11-03 11:18 Eric Long
2017-11-03 11:18 ` [PATCH v5 2/2] watchdog: Add Spreadtrum watchdog driver Eric Long
0 siblings, 1 reply; 4+ messages in thread
From: Eric Long @ 2017-11-03 11:18 UTC (permalink / raw)
To: Wim Van Sebroeck, Rob Herring, Mark Rutland
Cc: baolin.wang, Guenter Roeck, linux-watchdog, devicetree,
linux-kernel, eric.long
This patch adds the documentation for Spreadtrum watchdog driver.
Signed-off-by: Eric Long <eric.long@spreadtrum.com>
Acked-by: Rob Herring <robh@kernel.org>
---
Changes since v4:
- No updates.
Changes since v3:
- No updates.
Changes since v2:
- Add acked tag from Rob.
Changes since v1:
- No updates.
---
.../devicetree/bindings/watchdog/sprd-wdt.txt | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
create mode 100644 Documentation/devicetree/bindings/watchdog/sprd-wdt.txt
diff --git a/Documentation/devicetree/bindings/watchdog/sprd-wdt.txt b/Documentation/devicetree/bindings/watchdog/sprd-wdt.txt
new file mode 100644
index 0000000..aeaf3e0
--- /dev/null
+++ b/Documentation/devicetree/bindings/watchdog/sprd-wdt.txt
@@ -0,0 +1,19 @@
+Spreadtrum SoCs Watchdog timer
+
+Required properties:
+- compatible : Should be "sprd,sp9860-wdt".
+- reg : Specifies base physical address and size of the registers.
+- interrupts : Exactly one interrupt specifier.
+- timeout-sec : Contain the default watchdog timeout in seconds.
+- clock-names : Contain the input clock names.
+- clocks : Phandles to input clocks.
+
+Example:
+ watchdog: watchdog@40310000 {
+ compatible = "sprd,sp9860-wdt";
+ reg = <0 0x40310000 0 0x1000>;
+ interrupts = <GIC_SPI 61 IRQ_TYPE_LEVEL_HIGH>;
+ timeout-sec = <12>;
+ clock-names = "enable", "rtc_enable";
+ clocks = <&clk_aon_apb_gates1 8>, <&clk_aon_apb_rtc_gates 9>;
+ };
--
1.9.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v5 2/2] watchdog: Add Spreadtrum watchdog driver
2017-11-03 11:18 [PATCH v5 1/2] dt-bindings: watchdog: Add Spreadtrum watchdog documentation Eric Long
@ 2017-11-03 11:18 ` Eric Long
2017-11-03 13:48 ` [v5,2/2] " Guenter Roeck
0 siblings, 1 reply; 4+ messages in thread
From: Eric Long @ 2017-11-03 11:18 UTC (permalink / raw)
To: Wim Van Sebroeck, Rob Herring, Mark Rutland
Cc: baolin.wang, Guenter Roeck, linux-watchdog, devicetree,
linux-kernel, eric.long
This patch adds the watchdog driver for Spreadtrum SC9860 platform.
Signed-off-by: Eric Long <eric.long@spreadtrum.com>
---
Changes since v4:
- Remove sprd_wdt_remove().
- Add devm_add_action() for sprd_wdt_disable().
Changes since v3:
- Update Kconfig SPRD_WATCHDOG help messages.
- Correct the wrong spell words.
- Rename SPRD_WDT_CNT_HIGH_VALUE as SPRD_WDT_CNT_HIGH_SHIFT.
- Remove unused macor.
- Update sprd_wdt_set_pretimeout() api.
- Add wdt->wdd.timeout default value.
- Use devm_watchdog_register_device() to register wdt device.
- If module does not support NOWAYOUT, disable wdt when remove this driver.
- Call sprd_wdt_disable() every wdt suspend.
Changes since v2:
- Rename all the macors, add SPRD tag at the head of the macro names.
- Rename SPRD_WDT_CLK as SPRD_WTC_CNT_STEP.
- Remove the code which check timeout value at the wrong place.
- Add min/max timeout value limit.
- Remove set WDOG_HW_RUNNING status at sprd_wdt_enable().
- Add timeout/pretimeout judgment when set them.
- Support WATCHDOG_NOWAYOUT status.
Changes since v1:
- Use pretimeout instead of own implementation.
- Fix timeout loop when loading timeout values.
- use the infrastructure to read and set "timeout-sec" property.
- Add conditions when start or stop watchdog.
- Change the position of enabling watchdog.
- Other optimization.
---
drivers/watchdog/Kconfig | 8 +
drivers/watchdog/Makefile | 1 +
drivers/watchdog/sprd_wdt.c | 407 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 416 insertions(+)
create mode 100644 drivers/watchdog/sprd_wdt.c
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index c722cbf..3367a8c 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -787,6 +787,14 @@ config UNIPHIER_WATCHDOG
To compile this driver as a module, choose M here: the
module will be called uniphier_wdt.
+config SPRD_WATCHDOG
+ tristate "Spreadtrum watchdog support"
+ depends on ARCH_SPRD || COMPILE_TEST
+ select WATCHDOG_CORE
+ help
+ Say Y here to include watchdog timer supported
+ by Spreadtrum system.
+
# AVR32 Architecture
config AT32AP700X_WDT
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 56adf9f..187cca2 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -87,6 +87,7 @@ obj-$(CONFIG_ASPEED_WATCHDOG) += aspeed_wdt.o
obj-$(CONFIG_ZX2967_WATCHDOG) += zx2967_wdt.o
obj-$(CONFIG_STM32_WATCHDOG) += stm32_iwdg.o
obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o
+obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o
# AVR32 Architecture
obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o
diff --git a/drivers/watchdog/sprd_wdt.c b/drivers/watchdog/sprd_wdt.c
new file mode 100644
index 0000000..88f6f84
--- /dev/null
+++ b/drivers/watchdog/sprd_wdt.c
@@ -0,0 +1,407 @@
+/*
+ * Spreadtrum watchdog driver
+ * Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+
+#define SPRD_WDT_LOAD_LOW 0x0
+#define SPRD_WDT_LOAD_HIGH 0x4
+#define SPRD_WDT_CTRL 0x8
+#define SPRD_WDT_INT_CLR 0xc
+#define SPRD_WDT_INT_RAW 0x10
+#define SPRD_WDT_INT_MSK 0x14
+#define SPRD_WDT_CNT_LOW 0x18
+#define SPRD_WDT_CNT_HIGH 0x1c
+#define SPRD_WDT_LOCK 0x20
+#define SPRD_WDT_IRQ_LOAD_LOW 0x2c
+#define SPRD_WDT_IRQ_LOAD_HIGH 0x30
+
+/* WDT_CTRL */
+#define SPRD_WDT_INT_EN_BIT BIT(0)
+#define SPRD_WDT_CNT_EN_BIT BIT(1)
+#define SPRD_WDT_NEW_VER_EN BIT(2)
+#define SPRD_WDT_RST_EN_BIT BIT(3)
+
+/* WDT_INT_CLR */
+#define SPRD_WDT_INT_CLEAR_BIT BIT(0)
+#define SPRD_WDT_RST_CLEAR_BIT BIT(3)
+
+/* WDT_INT_RAW */
+#define SPRD_WDT_INT_RAW_BIT BIT(0)
+#define SPRD_WDT_RST_RAW_BIT BIT(3)
+#define SPRD_WDT_LD_BUSY_BIT BIT(4)
+
+/* 1s equal to 32768 counter steps */
+#define SPRD_WDT_CNT_STEP 32768
+
+#define SPRD_WDT_UNLOCK_KEY 0xe551
+#define SPRD_WDT_MIN_TIMEOUT 3
+#define SPRD_WDT_MAX_TIMEOUT 60
+
+#define SPRD_WDT_CNT_HIGH_SHIFT 16
+#define SPRD_WDT_LOW_VALUE_MASK GENMASK(15, 0)
+#define SPRD_WDT_LOAD_TIMEOUT 1000
+
+struct sprd_wdt {
+ void __iomem *base;
+ struct watchdog_device wdd;
+ struct clk *enable;
+ struct clk *rtc_enable;
+ unsigned int irq;
+};
+
+static inline struct sprd_wdt *to_sprd_wdt(struct watchdog_device *wdd)
+{
+ return container_of(wdd, struct sprd_wdt, wdd);
+}
+
+static inline void sprd_wdt_lock(void __iomem *addr)
+{
+ writel_relaxed(0x0, addr + SPRD_WDT_LOCK);
+}
+
+static inline void sprd_wdt_unlock(void __iomem *addr)
+{
+ writel_relaxed(SPRD_WDT_UNLOCK_KEY, addr + SPRD_WDT_LOCK);
+}
+
+static inline bool sprd_wdt_is_running(struct sprd_wdt *wdt)
+{
+ u32 val;
+
+ val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
+ return val & SPRD_WDT_NEW_VER_EN;
+}
+
+static irqreturn_t sprd_wdt_isr(int irq, void *dev_id)
+{
+ struct sprd_wdt *wdt = (struct sprd_wdt *)dev_id;
+
+ sprd_wdt_unlock(wdt->base);
+ writel_relaxed(SPRD_WDT_INT_CLEAR_BIT, wdt->base + SPRD_WDT_INT_CLR);
+ sprd_wdt_lock(wdt->base);
+ watchdog_notify_pretimeout(&wdt->wdd);
+ return IRQ_HANDLED;
+}
+
+static u32 sprd_wdt_get_cnt_value(struct sprd_wdt *wdt)
+{
+ u32 val;
+
+ val = readl_relaxed(wdt->base + SPRD_WDT_CNT_HIGH) <<
+ SPRD_WDT_CNT_HIGH_SHIFT;
+ val |= readl_relaxed(wdt->base + SPRD_WDT_CNT_LOW) &
+ SPRD_WDT_LOW_VALUE_MASK;
+
+ return val;
+}
+
+static int sprd_wdt_load_value(struct sprd_wdt *wdt, u32 timeout,
+ u32 pretimeout)
+{
+ u32 val, delay_cnt = 0;
+ u32 tmr_step = timeout * SPRD_WDT_CNT_STEP;
+ u32 prtmr_step = pretimeout * SPRD_WDT_CNT_STEP;
+
+ sprd_wdt_unlock(wdt->base);
+ writel_relaxed((tmr_step >> SPRD_WDT_CNT_HIGH_SHIFT) &
+ SPRD_WDT_LOW_VALUE_MASK, wdt->base + SPRD_WDT_LOAD_HIGH);
+ writel_relaxed((tmr_step & SPRD_WDT_LOW_VALUE_MASK),
+ wdt->base + SPRD_WDT_LOAD_LOW);
+ writel_relaxed((prtmr_step >> SPRD_WDT_CNT_HIGH_SHIFT) &
+ SPRD_WDT_LOW_VALUE_MASK,
+ wdt->base + SPRD_WDT_IRQ_LOAD_HIGH);
+ writel_relaxed(prtmr_step & SPRD_WDT_LOW_VALUE_MASK,
+ wdt->base + SPRD_WDT_IRQ_LOAD_LOW);
+ sprd_wdt_lock(wdt->base);
+
+ /*
+ * Waiting the load value operation done,
+ * it needs two or three RTC clock cycles.
+ */
+ do {
+ val = readl_relaxed(wdt->base + SPRD_WDT_INT_RAW);
+ if (!(val & SPRD_WDT_LD_BUSY_BIT))
+ break;
+
+ cpu_relax();
+ } while (delay_cnt++ < SPRD_WDT_LOAD_TIMEOUT);
+
+ if (delay_cnt >= SPRD_WDT_LOAD_TIMEOUT)
+ return -EBUSY;
+ return 0;
+}
+
+static int sprd_wdt_enable(struct sprd_wdt *wdt)
+{
+ u32 val;
+ int ret;
+
+ ret = clk_prepare_enable(wdt->enable);
+ if (ret)
+ return ret;
+ ret = clk_prepare_enable(wdt->rtc_enable);
+ if (ret)
+ return ret;
+
+ sprd_wdt_unlock(wdt->base);
+ val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
+ val |= SPRD_WDT_NEW_VER_EN;
+ writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
+ sprd_wdt_lock(wdt->base);
+ return 0;
+}
+
+static void sprd_wdt_disable(void *_data)
+{
+ struct sprd_wdt *wdt = _data;
+
+ sprd_wdt_unlock(wdt->base);
+ writel_relaxed(0x0, wdt->base + SPRD_WDT_CTRL);
+ sprd_wdt_lock(wdt->base);
+
+ clk_disable_unprepare(wdt->rtc_enable);
+ clk_disable_unprepare(wdt->enable);
+}
+
+static int sprd_wdt_start(struct watchdog_device *wdd)
+{
+ struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+ u32 val;
+ int ret;
+
+ ret = sprd_wdt_load_value(wdt, wdd->timeout, wdd->pretimeout);
+ if (ret)
+ return ret;
+
+ sprd_wdt_unlock(wdt->base);
+ val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
+ val |= SPRD_WDT_CNT_EN_BIT | SPRD_WDT_INT_EN_BIT | SPRD_WDT_RST_EN_BIT;
+ writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
+ sprd_wdt_lock(wdt->base);
+ set_bit(WDOG_HW_RUNNING, &wdd->status);
+
+ return 0;
+}
+
+static int sprd_wdt_stop(struct watchdog_device *wdd)
+{
+ struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+ u32 val;
+
+ sprd_wdt_unlock(wdt->base);
+ val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
+ val &= ~(SPRD_WDT_CNT_EN_BIT | SPRD_WDT_RST_EN_BIT |
+ SPRD_WDT_INT_EN_BIT);
+ writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
+ sprd_wdt_lock(wdt->base);
+ return 0;
+}
+
+static int sprd_wdt_set_timeout(struct watchdog_device *wdd,
+ u32 timeout)
+{
+ struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+
+ if (timeout == wdd->timeout)
+ return 0;
+
+ wdd->timeout = timeout;
+
+ return sprd_wdt_load_value(wdt, timeout, wdd->pretimeout);
+}
+
+static int sprd_wdt_set_pretimeout(struct watchdog_device *wdd,
+ u32 new_pretimeout)
+{
+ struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+
+ if (new_pretimeout < wdd->min_timeout)
+ return -EINVAL;
+
+ wdd->pretimeout = new_pretimeout;
+
+ return sprd_wdt_load_value(wdt, wdd->timeout, new_pretimeout);
+}
+
+static u32 sprd_wdt_get_timeleft(struct watchdog_device *wdd)
+{
+ struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+ u32 val;
+
+ val = sprd_wdt_get_cnt_value(wdt);
+ val = val / SPRD_WDT_CNT_STEP;
+
+ return val;
+}
+
+static const struct watchdog_ops sprd_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = sprd_wdt_start,
+ .stop = sprd_wdt_stop,
+ .set_timeout = sprd_wdt_set_timeout,
+ .set_pretimeout = sprd_wdt_set_pretimeout,
+ .get_timeleft = sprd_wdt_get_timeleft,
+};
+
+static const struct watchdog_info sprd_wdt_info = {
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_PRETIMEOUT |
+ WDIOF_MAGICCLOSE |
+ WDIOF_KEEPALIVEPING,
+ .identity = "Spreadtrum Watchdog Timer",
+};
+
+static int sprd_wdt_probe(struct platform_device *pdev)
+{
+ struct resource *wdt_res;
+ struct sprd_wdt *wdt;
+ int ret;
+
+ wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
+ if (!wdt)
+ return -ENOMEM;
+
+ wdt_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ wdt->base = devm_ioremap_resource(&pdev->dev, wdt_res);
+ if (IS_ERR(wdt->base)) {
+ dev_err(&pdev->dev, "failed to map memory resource\n");
+ return PTR_ERR(wdt->base);
+ }
+
+ wdt->enable = devm_clk_get(&pdev->dev, "enable");
+ if (IS_ERR(wdt->enable)) {
+ dev_err(&pdev->dev, "can't get the enable clock\n");
+ return PTR_ERR(wdt->enable);
+ }
+
+ wdt->rtc_enable = devm_clk_get(&pdev->dev, "rtc_enable");
+ if (IS_ERR(wdt->rtc_enable)) {
+ dev_err(&pdev->dev, "can't get the rtc enable clock\n");
+ return PTR_ERR(wdt->rtc_enable);
+ }
+
+ wdt->irq = platform_get_irq(pdev, 0);
+ if (wdt->irq < 0) {
+ dev_err(&pdev->dev, "failed to get IRQ resource\n");
+ return wdt->irq;
+ }
+
+ ret = devm_request_irq(&pdev->dev, wdt->irq, sprd_wdt_isr,
+ IRQF_NO_SUSPEND, "sprd-wdt", (void *)wdt);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register irq\n");
+ return ret;
+ }
+
+ wdt->wdd.info = &sprd_wdt_info;
+ wdt->wdd.ops = &sprd_wdt_ops;
+ wdt->wdd.parent = &pdev->dev;
+ wdt->wdd.min_timeout = SPRD_WDT_MIN_TIMEOUT;
+ wdt->wdd.max_timeout = SPRD_WDT_MAX_TIMEOUT;
+ wdt->wdd.timeout = SPRD_WDT_MAX_TIMEOUT;
+
+ ret = sprd_wdt_enable(wdt);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to enable wdt\n");
+ return ret;
+ }
+ ret = devm_add_action(&pdev->dev, sprd_wdt_disable, wdt);
+ if (ret) {
+ sprd_wdt_disable(wdt);
+ dev_err(&pdev->dev, "Failed to add wdt disable action\n");
+ return ret;
+ }
+
+ watchdog_set_nowayout(&wdt->wdd, WATCHDOG_NOWAYOUT);
+ watchdog_init_timeout(&wdt->wdd, 0, &pdev->dev);
+
+ ret = devm_watchdog_register_device(&pdev->dev, &wdt->wdd);
+ if (ret) {
+ sprd_wdt_disable(wdt);
+ dev_err(&pdev->dev, "failed to register watchdog\n");
+ return ret;
+ }
+ platform_set_drvdata(pdev, wdt);
+
+ return 0;
+}
+
+static int __maybe_unused sprd_wdt_pm_suspend(struct device *dev)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ struct sprd_wdt *wdt = dev_get_drvdata(dev);
+
+ if (watchdog_active(wdd))
+ sprd_wdt_stop(&wdt->wdd);
+ sprd_wdt_disable(wdt);
+
+ return 0;
+}
+
+static int __maybe_unused sprd_wdt_pm_resume(struct device *dev)
+{
+ struct watchdog_device *wdd = dev_get_drvdata(dev);
+ struct sprd_wdt *wdt = dev_get_drvdata(dev);
+ int ret;
+
+ ret = sprd_wdt_enable(wdt);
+ if (ret)
+ return ret;
+
+ if (watchdog_active(wdd)) {
+ ret = sprd_wdt_start(&wdt->wdd);
+ if (ret) {
+ sprd_wdt_disable(wdt);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops sprd_wdt_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(sprd_wdt_pm_suspend,
+ sprd_wdt_pm_resume)
+};
+
+static const struct of_device_id sprd_wdt_match_table[] = {
+ { .compatible = "sprd,sp9860-wdt", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sprd_wdt_match_table);
+
+static struct platform_driver sprd_watchdog_driver = {
+ .probe = sprd_wdt_probe,
+ .driver = {
+ .name = "sprd-wdt",
+ .of_match_table = sprd_wdt_match_table,
+ .pm = &sprd_wdt_pm_ops,
+ },
+};
+module_platform_driver(sprd_watchdog_driver);
+
+MODULE_AUTHOR("Eric Long <eric.long@spreadtrum.com>");
+MODULE_DESCRIPTION("Spreadtrum Watchdog Timer Controller Driver");
+MODULE_LICENSE("GPL v2");
--
1.9.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [v5,2/2] watchdog: Add Spreadtrum watchdog driver
2017-11-03 11:18 ` [PATCH v5 2/2] watchdog: Add Spreadtrum watchdog driver Eric Long
@ 2017-11-03 13:48 ` Guenter Roeck
2017-11-06 2:06 ` Eric Long
0 siblings, 1 reply; 4+ messages in thread
From: Guenter Roeck @ 2017-11-03 13:48 UTC (permalink / raw)
To: Eric Long
Cc: Wim Van Sebroeck, Rob Herring, Mark Rutland, baolin.wang,
linux-watchdog, devicetree, linux-kernel
On Fri, Nov 03, 2017 at 07:18:28PM +0800, Eric Long wrote:
> This patch adds the watchdog driver for Spreadtrum SC9860 platform.
>
> Signed-off-by: Eric Long <eric.long@spreadtrum.com>
> ---
> Changes since v4:
> - Remove sprd_wdt_remove().
> - Add devm_add_action() for sprd_wdt_disable().
>
> Changes since v3:
> - Update Kconfig SPRD_WATCHDOG help messages.
> - Correct the wrong spell words.
> - Rename SPRD_WDT_CNT_HIGH_VALUE as SPRD_WDT_CNT_HIGH_SHIFT.
> - Remove unused macor.
> - Update sprd_wdt_set_pretimeout() api.
> - Add wdt->wdd.timeout default value.
> - Use devm_watchdog_register_device() to register wdt device.
> - If module does not support NOWAYOUT, disable wdt when remove this driver.
> - Call sprd_wdt_disable() every wdt suspend.
>
> Changes since v2:
> - Rename all the macors, add SPRD tag at the head of the macro names.
> - Rename SPRD_WDT_CLK as SPRD_WTC_CNT_STEP.
> - Remove the code which check timeout value at the wrong place.
> - Add min/max timeout value limit.
> - Remove set WDOG_HW_RUNNING status at sprd_wdt_enable().
> - Add timeout/pretimeout judgment when set them.
> - Support WATCHDOG_NOWAYOUT status.
>
> Changes since v1:
> - Use pretimeout instead of own implementation.
> - Fix timeout loop when loading timeout values.
> - use the infrastructure to read and set "timeout-sec" property.
> - Add conditions when start or stop watchdog.
> - Change the position of enabling watchdog.
> - Other optimization.
> ---
> drivers/watchdog/Kconfig | 8 +
> drivers/watchdog/Makefile | 1 +
> drivers/watchdog/sprd_wdt.c | 407 ++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 416 insertions(+)
> create mode 100644 drivers/watchdog/sprd_wdt.c
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index c722cbf..3367a8c 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -787,6 +787,14 @@ config UNIPHIER_WATCHDOG
> To compile this driver as a module, choose M here: the
> module will be called uniphier_wdt.
>
> +config SPRD_WATCHDOG
> + tristate "Spreadtrum watchdog support"
> + depends on ARCH_SPRD || COMPILE_TEST
> + select WATCHDOG_CORE
> + help
> + Say Y here to include watchdog timer supported
> + by Spreadtrum system.
> +
> # AVR32 Architecture
>
> config AT32AP700X_WDT
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 56adf9f..187cca2 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -87,6 +87,7 @@ obj-$(CONFIG_ASPEED_WATCHDOG) += aspeed_wdt.o
> obj-$(CONFIG_ZX2967_WATCHDOG) += zx2967_wdt.o
> obj-$(CONFIG_STM32_WATCHDOG) += stm32_iwdg.o
> obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o
> +obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o
>
> # AVR32 Architecture
> obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o
> diff --git a/drivers/watchdog/sprd_wdt.c b/drivers/watchdog/sprd_wdt.c
> new file mode 100644
> index 0000000..88f6f84
> --- /dev/null
> +++ b/drivers/watchdog/sprd_wdt.c
> @@ -0,0 +1,407 @@
> +/*
> + * Spreadtrum watchdog driver
> + * Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful, but
> + * WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + * General Public License for more details.
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +#include <linux/watchdog.h>
> +
> +#define SPRD_WDT_LOAD_LOW 0x0
> +#define SPRD_WDT_LOAD_HIGH 0x4
> +#define SPRD_WDT_CTRL 0x8
> +#define SPRD_WDT_INT_CLR 0xc
> +#define SPRD_WDT_INT_RAW 0x10
> +#define SPRD_WDT_INT_MSK 0x14
> +#define SPRD_WDT_CNT_LOW 0x18
> +#define SPRD_WDT_CNT_HIGH 0x1c
> +#define SPRD_WDT_LOCK 0x20
> +#define SPRD_WDT_IRQ_LOAD_LOW 0x2c
> +#define SPRD_WDT_IRQ_LOAD_HIGH 0x30
> +
> +/* WDT_CTRL */
> +#define SPRD_WDT_INT_EN_BIT BIT(0)
> +#define SPRD_WDT_CNT_EN_BIT BIT(1)
> +#define SPRD_WDT_NEW_VER_EN BIT(2)
> +#define SPRD_WDT_RST_EN_BIT BIT(3)
> +
> +/* WDT_INT_CLR */
> +#define SPRD_WDT_INT_CLEAR_BIT BIT(0)
> +#define SPRD_WDT_RST_CLEAR_BIT BIT(3)
> +
> +/* WDT_INT_RAW */
> +#define SPRD_WDT_INT_RAW_BIT BIT(0)
> +#define SPRD_WDT_RST_RAW_BIT BIT(3)
> +#define SPRD_WDT_LD_BUSY_BIT BIT(4)
> +
> +/* 1s equal to 32768 counter steps */
> +#define SPRD_WDT_CNT_STEP 32768
> +
> +#define SPRD_WDT_UNLOCK_KEY 0xe551
> +#define SPRD_WDT_MIN_TIMEOUT 3
> +#define SPRD_WDT_MAX_TIMEOUT 60
> +
> +#define SPRD_WDT_CNT_HIGH_SHIFT 16
> +#define SPRD_WDT_LOW_VALUE_MASK GENMASK(15, 0)
> +#define SPRD_WDT_LOAD_TIMEOUT 1000
> +
> +struct sprd_wdt {
> + void __iomem *base;
> + struct watchdog_device wdd;
> + struct clk *enable;
> + struct clk *rtc_enable;
> + unsigned int irq;
> +};
> +
> +static inline struct sprd_wdt *to_sprd_wdt(struct watchdog_device *wdd)
> +{
> + return container_of(wdd, struct sprd_wdt, wdd);
> +}
> +
> +static inline void sprd_wdt_lock(void __iomem *addr)
> +{
> + writel_relaxed(0x0, addr + SPRD_WDT_LOCK);
> +}
> +
> +static inline void sprd_wdt_unlock(void __iomem *addr)
> +{
> + writel_relaxed(SPRD_WDT_UNLOCK_KEY, addr + SPRD_WDT_LOCK);
> +}
> +
> +static inline bool sprd_wdt_is_running(struct sprd_wdt *wdt)
> +{
> + u32 val;
> +
> + val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
> + return val & SPRD_WDT_NEW_VER_EN;
> +}
> +
> +static irqreturn_t sprd_wdt_isr(int irq, void *dev_id)
> +{
> + struct sprd_wdt *wdt = (struct sprd_wdt *)dev_id;
> +
> + sprd_wdt_unlock(wdt->base);
> + writel_relaxed(SPRD_WDT_INT_CLEAR_BIT, wdt->base + SPRD_WDT_INT_CLR);
> + sprd_wdt_lock(wdt->base);
> + watchdog_notify_pretimeout(&wdt->wdd);
> + return IRQ_HANDLED;
> +}
> +
> +static u32 sprd_wdt_get_cnt_value(struct sprd_wdt *wdt)
> +{
> + u32 val;
> +
> + val = readl_relaxed(wdt->base + SPRD_WDT_CNT_HIGH) <<
> + SPRD_WDT_CNT_HIGH_SHIFT;
> + val |= readl_relaxed(wdt->base + SPRD_WDT_CNT_LOW) &
> + SPRD_WDT_LOW_VALUE_MASK;
> +
> + return val;
> +}
> +
> +static int sprd_wdt_load_value(struct sprd_wdt *wdt, u32 timeout,
> + u32 pretimeout)
> +{
> + u32 val, delay_cnt = 0;
> + u32 tmr_step = timeout * SPRD_WDT_CNT_STEP;
> + u32 prtmr_step = pretimeout * SPRD_WDT_CNT_STEP;
> +
> + sprd_wdt_unlock(wdt->base);
> + writel_relaxed((tmr_step >> SPRD_WDT_CNT_HIGH_SHIFT) &
> + SPRD_WDT_LOW_VALUE_MASK, wdt->base + SPRD_WDT_LOAD_HIGH);
> + writel_relaxed((tmr_step & SPRD_WDT_LOW_VALUE_MASK),
> + wdt->base + SPRD_WDT_LOAD_LOW);
> + writel_relaxed((prtmr_step >> SPRD_WDT_CNT_HIGH_SHIFT) &
> + SPRD_WDT_LOW_VALUE_MASK,
> + wdt->base + SPRD_WDT_IRQ_LOAD_HIGH);
> + writel_relaxed(prtmr_step & SPRD_WDT_LOW_VALUE_MASK,
> + wdt->base + SPRD_WDT_IRQ_LOAD_LOW);
> + sprd_wdt_lock(wdt->base);
> +
> + /*
> + * Waiting the load value operation done,
> + * it needs two or three RTC clock cycles.
> + */
> + do {
> + val = readl_relaxed(wdt->base + SPRD_WDT_INT_RAW);
> + if (!(val & SPRD_WDT_LD_BUSY_BIT))
> + break;
> +
> + cpu_relax();
> + } while (delay_cnt++ < SPRD_WDT_LOAD_TIMEOUT);
> +
> + if (delay_cnt >= SPRD_WDT_LOAD_TIMEOUT)
> + return -EBUSY;
> + return 0;
> +}
> +
> +static int sprd_wdt_enable(struct sprd_wdt *wdt)
> +{
> + u32 val;
> + int ret;
> +
> + ret = clk_prepare_enable(wdt->enable);
> + if (ret)
> + return ret;
> + ret = clk_prepare_enable(wdt->rtc_enable);
> + if (ret)
> + return ret;
> +
> + sprd_wdt_unlock(wdt->base);
> + val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
> + val |= SPRD_WDT_NEW_VER_EN;
> + writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
> + sprd_wdt_lock(wdt->base);
> + return 0;
> +}
> +
> +static void sprd_wdt_disable(void *_data)
> +{
> + struct sprd_wdt *wdt = _data;
> +
> + sprd_wdt_unlock(wdt->base);
> + writel_relaxed(0x0, wdt->base + SPRD_WDT_CTRL);
> + sprd_wdt_lock(wdt->base);
> +
> + clk_disable_unprepare(wdt->rtc_enable);
> + clk_disable_unprepare(wdt->enable);
> +}
> +
> +static int sprd_wdt_start(struct watchdog_device *wdd)
> +{
> + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> + u32 val;
> + int ret;
> +
> + ret = sprd_wdt_load_value(wdt, wdd->timeout, wdd->pretimeout);
> + if (ret)
> + return ret;
> +
> + sprd_wdt_unlock(wdt->base);
> + val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
> + val |= SPRD_WDT_CNT_EN_BIT | SPRD_WDT_INT_EN_BIT | SPRD_WDT_RST_EN_BIT;
> + writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
> + sprd_wdt_lock(wdt->base);
> + set_bit(WDOG_HW_RUNNING, &wdd->status);
> +
> + return 0;
> +}
> +
> +static int sprd_wdt_stop(struct watchdog_device *wdd)
> +{
> + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> + u32 val;
> +
> + sprd_wdt_unlock(wdt->base);
> + val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
> + val &= ~(SPRD_WDT_CNT_EN_BIT | SPRD_WDT_RST_EN_BIT |
> + SPRD_WDT_INT_EN_BIT);
> + writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
> + sprd_wdt_lock(wdt->base);
> + return 0;
> +}
> +
> +static int sprd_wdt_set_timeout(struct watchdog_device *wdd,
> + u32 timeout)
> +{
> + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> +
> + if (timeout == wdd->timeout)
> + return 0;
> +
> + wdd->timeout = timeout;
> +
> + return sprd_wdt_load_value(wdt, timeout, wdd->pretimeout);
> +}
> +
> +static int sprd_wdt_set_pretimeout(struct watchdog_device *wdd,
> + u32 new_pretimeout)
> +{
> + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> +
> + if (new_pretimeout < wdd->min_timeout)
> + return -EINVAL;
> +
> + wdd->pretimeout = new_pretimeout;
> +
> + return sprd_wdt_load_value(wdt, wdd->timeout, new_pretimeout);
> +}
> +
> +static u32 sprd_wdt_get_timeleft(struct watchdog_device *wdd)
> +{
> + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> + u32 val;
> +
> + val = sprd_wdt_get_cnt_value(wdt);
> + val = val / SPRD_WDT_CNT_STEP;
> +
> + return val;
> +}
> +
> +static const struct watchdog_ops sprd_wdt_ops = {
> + .owner = THIS_MODULE,
> + .start = sprd_wdt_start,
> + .stop = sprd_wdt_stop,
> + .set_timeout = sprd_wdt_set_timeout,
> + .set_pretimeout = sprd_wdt_set_pretimeout,
> + .get_timeleft = sprd_wdt_get_timeleft,
> +};
> +
> +static const struct watchdog_info sprd_wdt_info = {
> + .options = WDIOF_SETTIMEOUT |
> + WDIOF_PRETIMEOUT |
> + WDIOF_MAGICCLOSE |
> + WDIOF_KEEPALIVEPING,
> + .identity = "Spreadtrum Watchdog Timer",
> +};
> +
> +static int sprd_wdt_probe(struct platform_device *pdev)
> +{
> + struct resource *wdt_res;
> + struct sprd_wdt *wdt;
> + int ret;
> +
> + wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
> + if (!wdt)
> + return -ENOMEM;
> +
> + wdt_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + wdt->base = devm_ioremap_resource(&pdev->dev, wdt_res);
> + if (IS_ERR(wdt->base)) {
> + dev_err(&pdev->dev, "failed to map memory resource\n");
> + return PTR_ERR(wdt->base);
> + }
> +
> + wdt->enable = devm_clk_get(&pdev->dev, "enable");
> + if (IS_ERR(wdt->enable)) {
> + dev_err(&pdev->dev, "can't get the enable clock\n");
> + return PTR_ERR(wdt->enable);
> + }
> +
> + wdt->rtc_enable = devm_clk_get(&pdev->dev, "rtc_enable");
> + if (IS_ERR(wdt->rtc_enable)) {
> + dev_err(&pdev->dev, "can't get the rtc enable clock\n");
> + return PTR_ERR(wdt->rtc_enable);
> + }
> +
> + wdt->irq = platform_get_irq(pdev, 0);
> + if (wdt->irq < 0) {
Please test compile your code and look out for warnings.
drivers/watchdog/sprd_wdt.c: In function ‘sprd_wdt_probe’:
drivers/watchdog/sprd_wdt.c:306:15: warning: comparison of unsigned expression <
0 is always false
wdt->irq is unsigned.
> + dev_err(&pdev->dev, "failed to get IRQ resource\n");
> + return wdt->irq;
> + }
> +
> + ret = devm_request_irq(&pdev->dev, wdt->irq, sprd_wdt_isr,
> + IRQF_NO_SUSPEND, "sprd-wdt", (void *)wdt);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to register irq\n");
> + return ret;
> + }
> +
> + wdt->wdd.info = &sprd_wdt_info;
> + wdt->wdd.ops = &sprd_wdt_ops;
> + wdt->wdd.parent = &pdev->dev;
> + wdt->wdd.min_timeout = SPRD_WDT_MIN_TIMEOUT;
> + wdt->wdd.max_timeout = SPRD_WDT_MAX_TIMEOUT;
> + wdt->wdd.timeout = SPRD_WDT_MAX_TIMEOUT;
> +
> + ret = sprd_wdt_enable(wdt);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to enable wdt\n");
> + return ret;
> + }
> + ret = devm_add_action(&pdev->dev, sprd_wdt_disable, wdt);
> + if (ret) {
> + sprd_wdt_disable(wdt);
> + dev_err(&pdev->dev, "Failed to add wdt disable action\n");
> + return ret;
> + }
> +
> + watchdog_set_nowayout(&wdt->wdd, WATCHDOG_NOWAYOUT);
> + watchdog_init_timeout(&wdt->wdd, 0, &pdev->dev);
> +
> + ret = devm_watchdog_register_device(&pdev->dev, &wdt->wdd);
> + if (ret) {
> + sprd_wdt_disable(wdt);
> + dev_err(&pdev->dev, "failed to register watchdog\n");
> + return ret;
> + }
> + platform_set_drvdata(pdev, wdt);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused sprd_wdt_pm_suspend(struct device *dev)
> +{
> + struct watchdog_device *wdd = dev_get_drvdata(dev);
> + struct sprd_wdt *wdt = dev_get_drvdata(dev);
> +
> + if (watchdog_active(wdd))
> + sprd_wdt_stop(&wdt->wdd);
> + sprd_wdt_disable(wdt);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused sprd_wdt_pm_resume(struct device *dev)
> +{
> + struct watchdog_device *wdd = dev_get_drvdata(dev);
> + struct sprd_wdt *wdt = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = sprd_wdt_enable(wdt);
> + if (ret)
> + return ret;
> +
> + if (watchdog_active(wdd)) {
> + ret = sprd_wdt_start(&wdt->wdd);
> + if (ret) {
> + sprd_wdt_disable(wdt);
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static const struct dev_pm_ops sprd_wdt_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(sprd_wdt_pm_suspend,
> + sprd_wdt_pm_resume)
> +};
> +
> +static const struct of_device_id sprd_wdt_match_table[] = {
> + { .compatible = "sprd,sp9860-wdt", },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, sprd_wdt_match_table);
> +
> +static struct platform_driver sprd_watchdog_driver = {
> + .probe = sprd_wdt_probe,
> + .driver = {
> + .name = "sprd-wdt",
> + .of_match_table = sprd_wdt_match_table,
> + .pm = &sprd_wdt_pm_ops,
> + },
> +};
> +module_platform_driver(sprd_watchdog_driver);
> +
> +MODULE_AUTHOR("Eric Long <eric.long@spreadtrum.com>");
> +MODULE_DESCRIPTION("Spreadtrum Watchdog Timer Controller Driver");
> +MODULE_LICENSE("GPL v2");
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [v5,2/2] watchdog: Add Spreadtrum watchdog driver
2017-11-03 13:48 ` [v5,2/2] " Guenter Roeck
@ 2017-11-06 2:06 ` Eric Long
0 siblings, 0 replies; 4+ messages in thread
From: Eric Long @ 2017-11-06 2:06 UTC (permalink / raw)
To: Guenter Roeck, eric.long
Cc: Wim Van Sebroeck, Rob Herring, Mark Rutland, baolin.wang,
linux-watchdog, devicetree, linux-kernel
On Fri, Nov 03, 2017 at 06:48:26AM -0700, Guenter Roeck wrote:
> On Fri, Nov 03, 2017 at 07:18:28PM +0800, Eric Long wrote:
> > This patch adds the watchdog driver for Spreadtrum SC9860 platform.
> >
> > Signed-off-by: Eric Long <eric.long@spreadtrum.com>
> > ---
> > Changes since v4:
> > - Remove sprd_wdt_remove().
> > - Add devm_add_action() for sprd_wdt_disable().
> >
> > Changes since v3:
> > - Update Kconfig SPRD_WATCHDOG help messages.
> > - Correct the wrong spell words.
> > - Rename SPRD_WDT_CNT_HIGH_VALUE as SPRD_WDT_CNT_HIGH_SHIFT.
> > - Remove unused macor.
> > - Update sprd_wdt_set_pretimeout() api.
> > - Add wdt->wdd.timeout default value.
> > - Use devm_watchdog_register_device() to register wdt device.
> > - If module does not support NOWAYOUT, disable wdt when remove this driver.
> > - Call sprd_wdt_disable() every wdt suspend.
> >
> > Changes since v2:
> > - Rename all the macors, add SPRD tag at the head of the macro names.
> > - Rename SPRD_WDT_CLK as SPRD_WTC_CNT_STEP.
> > - Remove the code which check timeout value at the wrong place.
> > - Add min/max timeout value limit.
> > - Remove set WDOG_HW_RUNNING status at sprd_wdt_enable().
> > - Add timeout/pretimeout judgment when set them.
> > - Support WATCHDOG_NOWAYOUT status.
> >
> > Changes since v1:
> > - Use pretimeout instead of own implementation.
> > - Fix timeout loop when loading timeout values.
> > - use the infrastructure to read and set "timeout-sec" property.
> > - Add conditions when start or stop watchdog.
> > - Change the position of enabling watchdog.
> > - Other optimization.
> > ---
> > drivers/watchdog/Kconfig | 8 +
> > drivers/watchdog/Makefile | 1 +
> > drivers/watchdog/sprd_wdt.c | 407 ++++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 416 insertions(+)
> > create mode 100644 drivers/watchdog/sprd_wdt.c
> >
> > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> > index c722cbf..3367a8c 100644
> > --- a/drivers/watchdog/Kconfig
> > +++ b/drivers/watchdog/Kconfig
> > @@ -787,6 +787,14 @@ config UNIPHIER_WATCHDOG
> > To compile this driver as a module, choose M here: the
> > module will be called uniphier_wdt.
> >
> > +config SPRD_WATCHDOG
> > + tristate "Spreadtrum watchdog support"
> > + depends on ARCH_SPRD || COMPILE_TEST
> > + select WATCHDOG_CORE
> > + help
> > + Say Y here to include watchdog timer supported
> > + by Spreadtrum system.
> > +
> > # AVR32 Architecture
> >
> > config AT32AP700X_WDT
> > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> > index 56adf9f..187cca2 100644
> > --- a/drivers/watchdog/Makefile
> > +++ b/drivers/watchdog/Makefile
> > @@ -87,6 +87,7 @@ obj-$(CONFIG_ASPEED_WATCHDOG) += aspeed_wdt.o
> > obj-$(CONFIG_ZX2967_WATCHDOG) += zx2967_wdt.o
> > obj-$(CONFIG_STM32_WATCHDOG) += stm32_iwdg.o
> > obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o
> > +obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o
> >
> > # AVR32 Architecture
> > obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o
> > diff --git a/drivers/watchdog/sprd_wdt.c b/drivers/watchdog/sprd_wdt.c
> > new file mode 100644
> > index 0000000..88f6f84
> > --- /dev/null
> > +++ b/drivers/watchdog/sprd_wdt.c
> > @@ -0,0 +1,407 @@
> > +/*
> > + * Spreadtrum watchdog driver
> > + * Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com
> > + *
> > + * This program is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU General Public License
> > + * version 2 as published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope that it will be useful, but
> > + * WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > + * General Public License for more details.
> > + */
> > +
> > +#include <linux/bitops.h>
> > +#include <linux/clk.h>
> > +#include <linux/device.h>
> > +#include <linux/err.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/io.h>
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_address.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/watchdog.h>
> > +
> > +#define SPRD_WDT_LOAD_LOW 0x0
> > +#define SPRD_WDT_LOAD_HIGH 0x4
> > +#define SPRD_WDT_CTRL 0x8
> > +#define SPRD_WDT_INT_CLR 0xc
> > +#define SPRD_WDT_INT_RAW 0x10
> > +#define SPRD_WDT_INT_MSK 0x14
> > +#define SPRD_WDT_CNT_LOW 0x18
> > +#define SPRD_WDT_CNT_HIGH 0x1c
> > +#define SPRD_WDT_LOCK 0x20
> > +#define SPRD_WDT_IRQ_LOAD_LOW 0x2c
> > +#define SPRD_WDT_IRQ_LOAD_HIGH 0x30
> > +
> > +/* WDT_CTRL */
> > +#define SPRD_WDT_INT_EN_BIT BIT(0)
> > +#define SPRD_WDT_CNT_EN_BIT BIT(1)
> > +#define SPRD_WDT_NEW_VER_EN BIT(2)
> > +#define SPRD_WDT_RST_EN_BIT BIT(3)
> > +
> > +/* WDT_INT_CLR */
> > +#define SPRD_WDT_INT_CLEAR_BIT BIT(0)
> > +#define SPRD_WDT_RST_CLEAR_BIT BIT(3)
> > +
> > +/* WDT_INT_RAW */
> > +#define SPRD_WDT_INT_RAW_BIT BIT(0)
> > +#define SPRD_WDT_RST_RAW_BIT BIT(3)
> > +#define SPRD_WDT_LD_BUSY_BIT BIT(4)
> > +
> > +/* 1s equal to 32768 counter steps */
> > +#define SPRD_WDT_CNT_STEP 32768
> > +
> > +#define SPRD_WDT_UNLOCK_KEY 0xe551
> > +#define SPRD_WDT_MIN_TIMEOUT 3
> > +#define SPRD_WDT_MAX_TIMEOUT 60
> > +
> > +#define SPRD_WDT_CNT_HIGH_SHIFT 16
> > +#define SPRD_WDT_LOW_VALUE_MASK GENMASK(15, 0)
> > +#define SPRD_WDT_LOAD_TIMEOUT 1000
> > +
> > +struct sprd_wdt {
> > + void __iomem *base;
> > + struct watchdog_device wdd;
> > + struct clk *enable;
> > + struct clk *rtc_enable;
> > + unsigned int irq;
> > +};
> > +
> > +static inline struct sprd_wdt *to_sprd_wdt(struct watchdog_device *wdd)
> > +{
> > + return container_of(wdd, struct sprd_wdt, wdd);
> > +}
> > +
> > +static inline void sprd_wdt_lock(void __iomem *addr)
> > +{
> > + writel_relaxed(0x0, addr + SPRD_WDT_LOCK);
> > +}
> > +
> > +static inline void sprd_wdt_unlock(void __iomem *addr)
> > +{
> > + writel_relaxed(SPRD_WDT_UNLOCK_KEY, addr + SPRD_WDT_LOCK);
> > +}
> > +
> > +static inline bool sprd_wdt_is_running(struct sprd_wdt *wdt)
> > +{
> > + u32 val;
> > +
> > + val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
> > + return val & SPRD_WDT_NEW_VER_EN;
> > +}
> > +
> > +static irqreturn_t sprd_wdt_isr(int irq, void *dev_id)
> > +{
> > + struct sprd_wdt *wdt = (struct sprd_wdt *)dev_id;
> > +
> > + sprd_wdt_unlock(wdt->base);
> > + writel_relaxed(SPRD_WDT_INT_CLEAR_BIT, wdt->base + SPRD_WDT_INT_CLR);
> > + sprd_wdt_lock(wdt->base);
> > + watchdog_notify_pretimeout(&wdt->wdd);
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static u32 sprd_wdt_get_cnt_value(struct sprd_wdt *wdt)
> > +{
> > + u32 val;
> > +
> > + val = readl_relaxed(wdt->base + SPRD_WDT_CNT_HIGH) <<
> > + SPRD_WDT_CNT_HIGH_SHIFT;
> > + val |= readl_relaxed(wdt->base + SPRD_WDT_CNT_LOW) &
> > + SPRD_WDT_LOW_VALUE_MASK;
> > +
> > + return val;
> > +}
> > +
> > +static int sprd_wdt_load_value(struct sprd_wdt *wdt, u32 timeout,
> > + u32 pretimeout)
> > +{
> > + u32 val, delay_cnt = 0;
> > + u32 tmr_step = timeout * SPRD_WDT_CNT_STEP;
> > + u32 prtmr_step = pretimeout * SPRD_WDT_CNT_STEP;
> > +
> > + sprd_wdt_unlock(wdt->base);
> > + writel_relaxed((tmr_step >> SPRD_WDT_CNT_HIGH_SHIFT) &
> > + SPRD_WDT_LOW_VALUE_MASK, wdt->base + SPRD_WDT_LOAD_HIGH);
> > + writel_relaxed((tmr_step & SPRD_WDT_LOW_VALUE_MASK),
> > + wdt->base + SPRD_WDT_LOAD_LOW);
> > + writel_relaxed((prtmr_step >> SPRD_WDT_CNT_HIGH_SHIFT) &
> > + SPRD_WDT_LOW_VALUE_MASK,
> > + wdt->base + SPRD_WDT_IRQ_LOAD_HIGH);
> > + writel_relaxed(prtmr_step & SPRD_WDT_LOW_VALUE_MASK,
> > + wdt->base + SPRD_WDT_IRQ_LOAD_LOW);
> > + sprd_wdt_lock(wdt->base);
> > +
> > + /*
> > + * Waiting the load value operation done,
> > + * it needs two or three RTC clock cycles.
> > + */
> > + do {
> > + val = readl_relaxed(wdt->base + SPRD_WDT_INT_RAW);
> > + if (!(val & SPRD_WDT_LD_BUSY_BIT))
> > + break;
> > +
> > + cpu_relax();
> > + } while (delay_cnt++ < SPRD_WDT_LOAD_TIMEOUT);
> > +
> > + if (delay_cnt >= SPRD_WDT_LOAD_TIMEOUT)
> > + return -EBUSY;
> > + return 0;
> > +}
> > +
> > +static int sprd_wdt_enable(struct sprd_wdt *wdt)
> > +{
> > + u32 val;
> > + int ret;
> > +
> > + ret = clk_prepare_enable(wdt->enable);
> > + if (ret)
> > + return ret;
> > + ret = clk_prepare_enable(wdt->rtc_enable);
> > + if (ret)
> > + return ret;
> > +
> > + sprd_wdt_unlock(wdt->base);
> > + val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
> > + val |= SPRD_WDT_NEW_VER_EN;
> > + writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
> > + sprd_wdt_lock(wdt->base);
> > + return 0;
> > +}
> > +
> > +static void sprd_wdt_disable(void *_data)
> > +{
> > + struct sprd_wdt *wdt = _data;
> > +
> > + sprd_wdt_unlock(wdt->base);
> > + writel_relaxed(0x0, wdt->base + SPRD_WDT_CTRL);
> > + sprd_wdt_lock(wdt->base);
> > +
> > + clk_disable_unprepare(wdt->rtc_enable);
> > + clk_disable_unprepare(wdt->enable);
> > +}
> > +
> > +static int sprd_wdt_start(struct watchdog_device *wdd)
> > +{
> > + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> > + u32 val;
> > + int ret;
> > +
> > + ret = sprd_wdt_load_value(wdt, wdd->timeout, wdd->pretimeout);
> > + if (ret)
> > + return ret;
> > +
> > + sprd_wdt_unlock(wdt->base);
> > + val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
> > + val |= SPRD_WDT_CNT_EN_BIT | SPRD_WDT_INT_EN_BIT | SPRD_WDT_RST_EN_BIT;
> > + writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
> > + sprd_wdt_lock(wdt->base);
> > + set_bit(WDOG_HW_RUNNING, &wdd->status);
> > +
> > + return 0;
> > +}
> > +
> > +static int sprd_wdt_stop(struct watchdog_device *wdd)
> > +{
> > + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> > + u32 val;
> > +
> > + sprd_wdt_unlock(wdt->base);
> > + val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
> > + val &= ~(SPRD_WDT_CNT_EN_BIT | SPRD_WDT_RST_EN_BIT |
> > + SPRD_WDT_INT_EN_BIT);
> > + writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
> > + sprd_wdt_lock(wdt->base);
> > + return 0;
> > +}
> > +
> > +static int sprd_wdt_set_timeout(struct watchdog_device *wdd,
> > + u32 timeout)
> > +{
> > + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> > +
> > + if (timeout == wdd->timeout)
> > + return 0;
> > +
> > + wdd->timeout = timeout;
> > +
> > + return sprd_wdt_load_value(wdt, timeout, wdd->pretimeout);
> > +}
> > +
> > +static int sprd_wdt_set_pretimeout(struct watchdog_device *wdd,
> > + u32 new_pretimeout)
> > +{
> > + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> > +
> > + if (new_pretimeout < wdd->min_timeout)
> > + return -EINVAL;
> > +
> > + wdd->pretimeout = new_pretimeout;
> > +
> > + return sprd_wdt_load_value(wdt, wdd->timeout, new_pretimeout);
> > +}
> > +
> > +static u32 sprd_wdt_get_timeleft(struct watchdog_device *wdd)
> > +{
> > + struct sprd_wdt *wdt = to_sprd_wdt(wdd);
> > + u32 val;
> > +
> > + val = sprd_wdt_get_cnt_value(wdt);
> > + val = val / SPRD_WDT_CNT_STEP;
> > +
> > + return val;
> > +}
> > +
> > +static const struct watchdog_ops sprd_wdt_ops = {
> > + .owner = THIS_MODULE,
> > + .start = sprd_wdt_start,
> > + .stop = sprd_wdt_stop,
> > + .set_timeout = sprd_wdt_set_timeout,
> > + .set_pretimeout = sprd_wdt_set_pretimeout,
> > + .get_timeleft = sprd_wdt_get_timeleft,
> > +};
> > +
> > +static const struct watchdog_info sprd_wdt_info = {
> > + .options = WDIOF_SETTIMEOUT |
> > + WDIOF_PRETIMEOUT |
> > + WDIOF_MAGICCLOSE |
> > + WDIOF_KEEPALIVEPING,
> > + .identity = "Spreadtrum Watchdog Timer",
> > +};
> > +
> > +static int sprd_wdt_probe(struct platform_device *pdev)
> > +{
> > + struct resource *wdt_res;
> > + struct sprd_wdt *wdt;
> > + int ret;
> > +
> > + wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
> > + if (!wdt)
> > + return -ENOMEM;
> > +
> > + wdt_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > + wdt->base = devm_ioremap_resource(&pdev->dev, wdt_res);
> > + if (IS_ERR(wdt->base)) {
> > + dev_err(&pdev->dev, "failed to map memory resource\n");
> > + return PTR_ERR(wdt->base);
> > + }
> > +
> > + wdt->enable = devm_clk_get(&pdev->dev, "enable");
> > + if (IS_ERR(wdt->enable)) {
> > + dev_err(&pdev->dev, "can't get the enable clock\n");
> > + return PTR_ERR(wdt->enable);
> > + }
> > +
> > + wdt->rtc_enable = devm_clk_get(&pdev->dev, "rtc_enable");
> > + if (IS_ERR(wdt->rtc_enable)) {
> > + dev_err(&pdev->dev, "can't get the rtc enable clock\n");
> > + return PTR_ERR(wdt->rtc_enable);
> > + }
> > +
> > + wdt->irq = platform_get_irq(pdev, 0);
> > + if (wdt->irq < 0) {
>
> Please test compile your code and look out for warnings.
>
> drivers/watchdog/sprd_wdt.c: In function ‘sprd_wdt_probe’:
> drivers/watchdog/sprd_wdt.c:306:15: warning: comparison of unsigned expression <
> 0 is always false
>
> wdt->irq is unsigned.
>
Yes, you are right, I will fix it. Thank you.
> > + dev_err(&pdev->dev, "failed to get IRQ resource\n");
> > + return wdt->irq;
> > + }
> > +
> > + ret = devm_request_irq(&pdev->dev, wdt->irq, sprd_wdt_isr,
> > + IRQF_NO_SUSPEND, "sprd-wdt", (void *)wdt);
> > + if (ret) {
> > + dev_err(&pdev->dev, "failed to register irq\n");
> > + return ret;
> > + }
> > +
> > + wdt->wdd.info = &sprd_wdt_info;
> > + wdt->wdd.ops = &sprd_wdt_ops;
> > + wdt->wdd.parent = &pdev->dev;
> > + wdt->wdd.min_timeout = SPRD_WDT_MIN_TIMEOUT;
> > + wdt->wdd.max_timeout = SPRD_WDT_MAX_TIMEOUT;
> > + wdt->wdd.timeout = SPRD_WDT_MAX_TIMEOUT;
> > +
> > + ret = sprd_wdt_enable(wdt);
> > + if (ret) {
> > + dev_err(&pdev->dev, "failed to enable wdt\n");
> > + return ret;
> > + }
> > + ret = devm_add_action(&pdev->dev, sprd_wdt_disable, wdt);
> > + if (ret) {
> > + sprd_wdt_disable(wdt);
> > + dev_err(&pdev->dev, "Failed to add wdt disable action\n");
> > + return ret;
> > + }
> > +
> > + watchdog_set_nowayout(&wdt->wdd, WATCHDOG_NOWAYOUT);
> > + watchdog_init_timeout(&wdt->wdd, 0, &pdev->dev);
> > +
> > + ret = devm_watchdog_register_device(&pdev->dev, &wdt->wdd);
> > + if (ret) {
> > + sprd_wdt_disable(wdt);
> > + dev_err(&pdev->dev, "failed to register watchdog\n");
> > + return ret;
> > + }
> > + platform_set_drvdata(pdev, wdt);
> > +
> > + return 0;
> > +}
> > +
> > +static int __maybe_unused sprd_wdt_pm_suspend(struct device *dev)
> > +{
> > + struct watchdog_device *wdd = dev_get_drvdata(dev);
> > + struct sprd_wdt *wdt = dev_get_drvdata(dev);
> > +
> > + if (watchdog_active(wdd))
> > + sprd_wdt_stop(&wdt->wdd);
> > + sprd_wdt_disable(wdt);
> > +
> > + return 0;
> > +}
> > +
> > +static int __maybe_unused sprd_wdt_pm_resume(struct device *dev)
> > +{
> > + struct watchdog_device *wdd = dev_get_drvdata(dev);
> > + struct sprd_wdt *wdt = dev_get_drvdata(dev);
> > + int ret;
> > +
> > + ret = sprd_wdt_enable(wdt);
> > + if (ret)
> > + return ret;
> > +
> > + if (watchdog_active(wdd)) {
> > + ret = sprd_wdt_start(&wdt->wdd);
> > + if (ret) {
> > + sprd_wdt_disable(wdt);
> > + return ret;
> > + }
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static const struct dev_pm_ops sprd_wdt_pm_ops = {
> > + SET_SYSTEM_SLEEP_PM_OPS(sprd_wdt_pm_suspend,
> > + sprd_wdt_pm_resume)
> > +};
> > +
> > +static const struct of_device_id sprd_wdt_match_table[] = {
> > + { .compatible = "sprd,sp9860-wdt", },
> > + {},
> > +};
> > +MODULE_DEVICE_TABLE(of, sprd_wdt_match_table);
> > +
> > +static struct platform_driver sprd_watchdog_driver = {
> > + .probe = sprd_wdt_probe,
> > + .driver = {
> > + .name = "sprd-wdt",
> > + .of_match_table = sprd_wdt_match_table,
> > + .pm = &sprd_wdt_pm_ops,
> > + },
> > +};
> > +module_platform_driver(sprd_watchdog_driver);
> > +
> > +MODULE_AUTHOR("Eric Long <eric.long@spreadtrum.com>");
> > +MODULE_DESCRIPTION("Spreadtrum Watchdog Timer Controller Driver");
> > +MODULE_LICENSE("GPL v2");
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2017-11-06 2:14 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-11-03 11:18 [PATCH v5 1/2] dt-bindings: watchdog: Add Spreadtrum watchdog documentation Eric Long
2017-11-03 11:18 ` [PATCH v5 2/2] watchdog: Add Spreadtrum watchdog driver Eric Long
2017-11-03 13:48 ` [v5,2/2] " Guenter Roeck
2017-11-06 2:06 ` Eric Long
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