diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-06-26 11:34:35 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-06-26 11:34:35 -0700 |
commit | 4aa705b18bf17c4ff33ff7bbcd3f0c596443fa81 (patch) | |
tree | 3b166bff290d123ccaa88598ad2d45be67f5b358 /drivers/watchdog/bcm2835_wdt.c | |
parent | c11d716218910c3aa2bac1bb641e6086ad649555 (diff) | |
parent | 2879e43f09122f8b3ef5456e3d7e48716b086e60 (diff) |
Merge tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC platform support updates from Kevin Hilman:
"Our SoC branch usually contains expanded support for new SoCs and
other core platform code. Some highlights from this round:
- sunxi: SMP support for A23 SoC
- socpga: big-endian support
- pxa: conversion to common clock framework
- bcm: SMP support for BCM63138
- imx: support new I.MX7D SoC
- zte: basic support for ZX296702 SoC"
* tag 'armsoc-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (134 commits)
ARM: zx: Add basic defconfig support for ZX296702
ARM: dts: zx: add an initial zx296702 dts and doc
clk: zx: add clock support to zx296702
dt-bindings: Add #defines for ZTE ZX296702 clocks
ARM: socfpga: fix build error due to secondary_startup
MAINTAINERS: ARM64: EXYNOS: Extend entry for ARM64 DTS
ARM: ep93xx: simone: support for SPI-based MMC/SD cards
MAINTAINERS: update Shawn's email to use kernel.org one
ARM: socfpga: support suspend to ram
ARM: socfpga: add CPU_METHOD_OF_DECLARE for Arria 10
ARM: socfpga: use CPU_METHOD_OF_DECLARE for socfpga_cyclone5
ARM: EXYNOS: register power domain driver from core_initcall
ARM: EXYNOS: use PS_HOLD based poweroff for all supported SoCs
ARM: SAMSUNG: Constify platform_device_id
ARM: EXYNOS: Constify irq_domain_ops
ARM: EXYNOS: add coupled cpuidle support for Exynos3250
ARM: EXYNOS: add exynos_get_boot_addr() helper
ARM: EXYNOS: add exynos_set_boot_addr() helper
ARM: EXYNOS: make exynos_core_restart() less verbose
ARM: EXYNOS: fix exynos_boot_secondary() return value on timeout
...
Diffstat (limited to 'drivers/watchdog/bcm2835_wdt.c')
-rw-r--r-- | drivers/watchdog/bcm2835_wdt.c | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/drivers/watchdog/bcm2835_wdt.c b/drivers/watchdog/bcm2835_wdt.c index 2b5a9bbf80b7..7116968dee12 100644 --- a/drivers/watchdog/bcm2835_wdt.c +++ b/drivers/watchdog/bcm2835_wdt.c @@ -13,20 +13,25 @@ * option) any later version. */ +#include <linux/delay.h> +#include <linux/reboot.h> #include <linux/types.h> #include <linux/module.h> #include <linux/io.h> #include <linux/watchdog.h> #include <linux/platform_device.h> #include <linux/of_address.h> +#include <linux/of_platform.h> #define PM_RSTC 0x1c +#define PM_RSTS 0x20 #define PM_WDOG 0x24 #define PM_PASSWORD 0x5a000000 #define PM_WDOG_TIME_SET 0x000fffff #define PM_RSTC_WRCFG_CLR 0xffffffcf +#define PM_RSTS_HADWRH_SET 0x00000040 #define PM_RSTC_WRCFG_SET 0x00000030 #define PM_RSTC_WRCFG_FULL_RESET 0x00000020 #define PM_RSTC_RESET 0x00000102 @@ -37,6 +42,7 @@ struct bcm2835_wdt { void __iomem *base; spinlock_t lock; + struct notifier_block restart_handler; }; static unsigned int heartbeat; @@ -106,6 +112,53 @@ static struct watchdog_device bcm2835_wdt_wdd = { .timeout = WDOG_TICKS_TO_SECS(PM_WDOG_TIME_SET), }; +static int +bcm2835_restart(struct notifier_block *this, unsigned long mode, void *cmd) +{ + struct bcm2835_wdt *wdt = container_of(this, struct bcm2835_wdt, + restart_handler); + u32 val; + + /* use a timeout of 10 ticks (~150us) */ + writel_relaxed(10 | PM_PASSWORD, wdt->base + PM_WDOG); + val = readl_relaxed(wdt->base + PM_RSTC); + val &= PM_RSTC_WRCFG_CLR; + val |= PM_PASSWORD | PM_RSTC_WRCFG_FULL_RESET; + writel_relaxed(val, wdt->base + PM_RSTC); + + /* No sleeping, possibly atomic. */ + mdelay(1); + + return 0; +} + +/* + * We can't really power off, but if we do the normal reset scheme, and + * indicate to bootcode.bin not to reboot, then most of the chip will be + * powered off. + */ +static void bcm2835_power_off(void) +{ + struct device_node *np = + of_find_compatible_node(NULL, NULL, "brcm,bcm2835-pm-wdt"); + struct platform_device *pdev = of_find_device_by_node(np); + struct bcm2835_wdt *wdt = platform_get_drvdata(pdev); + u32 val; + + /* + * We set the watchdog hard reset bit here to distinguish this reset + * from the normal (full) reset. bootcode.bin will not reboot after a + * hard reset. + */ + val = readl_relaxed(wdt->base + PM_RSTS); + val &= PM_RSTC_WRCFG_CLR; + val |= PM_PASSWORD | PM_RSTS_HADWRH_SET; + writel_relaxed(val, wdt->base + PM_RSTS); + + /* Continue with normal reset mechanism */ + bcm2835_restart(&wdt->restart_handler, REBOOT_HARD, NULL); +} + static int bcm2835_wdt_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -136,6 +189,12 @@ static int bcm2835_wdt_probe(struct platform_device *pdev) return err; } + wdt->restart_handler.notifier_call = bcm2835_restart; + wdt->restart_handler.priority = 128; + register_restart_handler(&wdt->restart_handler); + if (pm_power_off == NULL) + pm_power_off = bcm2835_power_off; + dev_info(dev, "Broadcom BCM2835 watchdog timer"); return 0; } @@ -144,6 +203,9 @@ static int bcm2835_wdt_remove(struct platform_device *pdev) { struct bcm2835_wdt *wdt = platform_get_drvdata(pdev); + unregister_restart_handler(&wdt->restart_handler); + if (pm_power_off == bcm2835_power_off) + pm_power_off = NULL; watchdog_unregister_device(&bcm2835_wdt_wdd); iounmap(wdt->base); |