From 710322ba8cc6c1ce98779ee02e1fdb6571700c47 Mon Sep 17 00:00:00 2001 From: Hauke Mehrtens Date: Sun, 20 Aug 2017 00:18:11 +0200 Subject: watchdog: lantiq: access boot cause register through regmap This patch avoids accessing the function ltq_reset_cause() and directly accesses the register given over the syscon interface. The syscon interface will be implemented for the xway SoCs for the falcon SoCs the ltq_reset_cause() function never worked, because a wrong offset was used. Signed-off-by: Hauke Mehrtens Acked-by: Guenter Roeck Cc: martin.blumenstingl@googlemail.com Cc: john@phrozen.org Cc: robh@kernel.org Cc: andy.shevchenko@gmail.com Cc: p.zabel@pengutronix.de Cc: kishon@ti.com Cc: mark.rutland@arm.com Cc: linux-mips@linux-mips.org Cc: linux-mtd@lists.infradead.org Cc: linux-watchdog@vger.kernel.org Cc: devicetree@vger.kernel.org Cc: linux-spi@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17123/ Signed-off-by: Ralf Baechle --- drivers/watchdog/lantiq_wdt.c | 74 ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 69 insertions(+), 5 deletions(-) diff --git a/drivers/watchdog/lantiq_wdt.c b/drivers/watchdog/lantiq_wdt.c index e0823677d8c1..7f43cefa0eae 100644 --- a/drivers/watchdog/lantiq_wdt.c +++ b/drivers/watchdog/lantiq_wdt.c @@ -4,6 +4,7 @@ * by the Free Software Foundation. * * Copyright (C) 2010 John Crispin + * Copyright (C) 2017 Hauke Mehrtens * Based on EP93xx wdt driver */ @@ -17,9 +18,20 @@ #include #include #include +#include +#include #include +#define LTQ_XRX_RCU_RST_STAT 0x0014 +#define LTQ_XRX_RCU_RST_STAT_WDT BIT(31) + +/* CPU0 Reset Source Register */ +#define LTQ_FALCON_SYS1_CPU0RS 0x0060 +/* reset cause mask */ +#define LTQ_FALCON_SYS1_CPU0RS_MASK 0x0007 +#define LTQ_FALCON_SYS1_CPU0RS_WDT 0x02 + /* * Section 3.4 of the datasheet * The password sequence protects the WDT control register from unintended @@ -186,16 +198,70 @@ static struct miscdevice ltq_wdt_miscdev = { .fops = <q_wdt_fops, }; +typedef int (*ltq_wdt_bootstatus_set)(struct platform_device *pdev); + +static int ltq_wdt_bootstatus_xrx(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct regmap *rcu_regmap; + u32 val; + int err; + + rcu_regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "regmap"); + if (IS_ERR(rcu_regmap)) + return PTR_ERR(rcu_regmap); + + err = regmap_read(rcu_regmap, LTQ_XRX_RCU_RST_STAT, &val); + if (err) + return err; + + if (val & LTQ_XRX_RCU_RST_STAT_WDT) + ltq_wdt_bootstatus = WDIOF_CARDRESET; + + return 0; +} + +static int ltq_wdt_bootstatus_falcon(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct regmap *rcu_regmap; + u32 val; + int err; + + rcu_regmap = syscon_regmap_lookup_by_phandle(dev->of_node, + "lantiq,rcu"); + if (IS_ERR(rcu_regmap)) + return PTR_ERR(rcu_regmap); + + err = regmap_read(rcu_regmap, LTQ_FALCON_SYS1_CPU0RS, &val); + if (err) + return err; + + if ((val & LTQ_FALCON_SYS1_CPU0RS_MASK) == LTQ_FALCON_SYS1_CPU0RS_WDT) + ltq_wdt_bootstatus = WDIOF_CARDRESET; + + return 0; +} + static int ltq_wdt_probe(struct platform_device *pdev) { struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); struct clk *clk; + ltq_wdt_bootstatus_set ltq_wdt_bootstatus_set; + int ret; ltq_wdt_membase = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(ltq_wdt_membase)) return PTR_ERR(ltq_wdt_membase); + ltq_wdt_bootstatus_set = of_device_get_match_data(&pdev->dev); + if (ltq_wdt_bootstatus_set) { + ret = ltq_wdt_bootstatus_set(pdev); + if (ret) + return ret; + } + /* we do not need to enable the clock as it is always running */ clk = clk_get_io(); if (IS_ERR(clk)) { @@ -205,10 +271,6 @@ ltq_wdt_probe(struct platform_device *pdev) ltq_io_region_clk_rate = clk_get_rate(clk); clk_put(clk); - /* find out if the watchdog caused the last reboot */ - if (ltq_reset_cause() == LTQ_RST_CAUSE_WDTRST) - ltq_wdt_bootstatus = WDIOF_CARDRESET; - dev_info(&pdev->dev, "Init done\n"); return misc_register(<q_wdt_miscdev); } @@ -222,7 +284,9 @@ ltq_wdt_remove(struct platform_device *pdev) } static const struct of_device_id ltq_wdt_match[] = { - { .compatible = "lantiq,wdt" }, + { .compatible = "lantiq,wdt", .data = NULL}, + { .compatible = "lantiq,xrx100-wdt", .data = ltq_wdt_bootstatus_xrx }, + { .compatible = "lantiq,falcon-wdt", .data = ltq_wdt_bootstatus_falcon }, {}, }; MODULE_DEVICE_TABLE(of, ltq_wdt_match); -- cgit v1.2.3