From: "yong.liang" yong.liang@mediatek.com
Add reset controller API in watchdog driver. Besides watchdog, MTK toprgu module also provide sub-system (eg, audio, camera, codec and connectivity) software reset functionality.
Signed-off-by: yong.liang yong.liang@mediatek.com --- drivers/watchdog/Kconfig | 1 + drivers/watchdog/mtk_wdt.c | 111 ++++++++++++++++++++++++++++++++++++- 2 files changed, 111 insertions(+), 1 deletion(-)
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 2e07caab9db2..629249fe5305 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -717,6 +717,7 @@ config MEDIATEK_WATCHDOG tristate "Mediatek SoCs watchdog support" depends on ARCH_MEDIATEK || COMPILE_TEST select WATCHDOG_CORE + select RESET_CONTROLLER help Say Y here to include support for the watchdog timer in Mediatek SoCs. diff --git a/drivers/watchdog/mtk_wdt.c b/drivers/watchdog/mtk_wdt.c index 9c3d0033260d..d29484c7940a 100644 --- a/drivers/watchdog/mtk_wdt.c +++ b/drivers/watchdog/mtk_wdt.c @@ -9,6 +9,9 @@ * Based on sunxi_wdt.c */
+#include <dt-bindings/reset-controller/mt2712-resets.h> +#include <dt-bindings/reset-controller/mt8183-resets.h> +#include <linux/delay.h> #include <linux/err.h> #include <linux/init.h> #include <linux/io.h> @@ -16,10 +19,12 @@ #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/of.h> +#include <linux/of_device.h> #include <linux/platform_device.h> +#include <linux/reset-controller.h> +#include <linux/slab.h> #include <linux/types.h> #include <linux/watchdog.h> -#include <linux/delay.h>
#define WDT_MAX_TIMEOUT 31 #define WDT_MIN_TIMEOUT 1 @@ -44,6 +49,9 @@ #define WDT_SWRST 0x14 #define WDT_SWRST_KEY 0x1209
+#define WDT_SWSYSRST 0x18U +#define WDT_SWSYS_RST_KEY 0x88000000 + #define DRV_NAME "mtk-wdt" #define DRV_VERSION "1.0"
@@ -53,8 +61,99 @@ static unsigned int timeout; struct mtk_wdt_dev { struct watchdog_device wdt_dev; void __iomem *wdt_base; + spinlock_t lock; /* protects WDT_SWSYSRST reg */ + struct reset_controller_dev rcdev; +}; + +struct mtk_wdt_data { + int sw_rst_num; };
+static const struct mtk_wdt_data mt2712_data = { + .sw_rst_num = MT2712_TOPRGU_SW_RST_NUM, +}; + +static const struct mtk_wdt_data mt8183_data = { + .sw_rst_num = MT8183_TOPRGU_SW_RST_NUM, +}; + +static int toprgu_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + unsigned int tmp; + unsigned long flags; + struct mtk_wdt_dev *data = + container_of(rcdev, struct mtk_wdt_dev, rcdev); + + spin_lock_irqsave(&data->lock, flags); + + tmp = __raw_readl(data->wdt_base + WDT_SWSYSRST); + tmp |= BIT(id); + tmp |= WDT_SWSYS_RST_KEY; + writel(tmp, data->wdt_base + WDT_SWSYSRST); + + spin_unlock_irqrestore(&data->lock, flags); + + return 0; +} + +static int toprgu_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + unsigned int tmp; + unsigned long flags; + struct mtk_wdt_dev *data = + container_of(rcdev, struct mtk_wdt_dev, rcdev); + + spin_lock_irqsave(&data->lock, flags); + + tmp = __raw_readl(data->wdt_base + WDT_SWSYSRST); + tmp &= ~BIT(id); + tmp |= WDT_SWSYS_RST_KEY; + writel(tmp, data->wdt_base + WDT_SWSYSRST); + + spin_unlock_irqrestore(&data->lock, flags); + + return 0; +} + +static int toprgu_reset(struct reset_controller_dev *rcdev, + unsigned long id) +{ + int ret; + + ret = toprgu_reset_assert(rcdev, id); + if (ret) + return ret; + + return toprgu_reset_deassert(rcdev, id); +} + +static const struct reset_control_ops toprgu_reset_ops = { + .assert = toprgu_reset_assert, + .deassert = toprgu_reset_deassert, + .reset = toprgu_reset, +}; + +static int toprgu_register_reset_controller(struct platform_device *pdev, + int rst_num) +{ + int ret; + struct mtk_wdt_dev *mtk_wdt = platform_get_drvdata(pdev); + + spin_lock_init(&mtk_wdt->lock); + + mtk_wdt->rcdev.owner = THIS_MODULE; + mtk_wdt->rcdev.nr_resets = rst_num; + mtk_wdt->rcdev.ops = &toprgu_reset_ops; + mtk_wdt->rcdev.of_node = pdev->dev.of_node; + ret = reset_controller_register(&mtk_wdt->rcdev); + if (ret != 0) + dev_err(&pdev->dev, + "couldn't register wdt reset controller: %d\n", ret); + return ret; +} + static int mtk_wdt_restart(struct watchdog_device *wdt_dev, unsigned long action, void *data) { @@ -155,6 +254,7 @@ static int mtk_wdt_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct mtk_wdt_dev *mtk_wdt; + struct mtk_wdt_data *wdt_data; int err;
mtk_wdt = devm_kzalloc(dev, sizeof(*mtk_wdt), GFP_KERNEL); @@ -190,6 +290,13 @@ static int mtk_wdt_probe(struct platform_device *pdev) dev_info(dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)\n", mtk_wdt->wdt_dev.timeout, nowayout);
+ wdt_data = (struct mtk_wdt_data *)of_device_get_match_data(dev); + if (wdt_data) { + err = toprgu_register_reset_controller(pdev, + wdt_data->sw_rst_num); + if (err) + return err; + } return 0; }
@@ -218,7 +325,9 @@ static int mtk_wdt_resume(struct device *dev) #endif
static const struct of_device_id mtk_wdt_dt_ids[] = { + { .compatible = "mediatek,mt2712-wdt", .data = &mt2712_data }, { .compatible = "mediatek,mt6589-wdt" }, + { .compatible = "mediatek,mt8183-wdt", .data = &mt8183_data }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, mtk_wdt_dt_ids);