From 81fbc5ef9b22df2e2198dd0c530719a263a8d1c5 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Tue, 21 Dec 2010 19:56:17 -0700 Subject: OMAP2+: wd_timer: separate watchdog disable code from the rest of mach-omap2/devices.c Split the wd_timer disable code out into its own file, mach-omap2/wd_timer.c; it belongs in its own file rather than cluttering up devices.c. Signed-off-by: Paul Walmsley Cc: Charulatha Varadarajan --- arch/arm/mach-omap2/wd_timer.c | 68 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 arch/arm/mach-omap2/wd_timer.c (limited to 'arch/arm/mach-omap2/wd_timer.c') diff --git a/arch/arm/mach-omap2/wd_timer.c b/arch/arm/mach-omap2/wd_timer.c new file mode 100644 index 0000000..06c256d --- /dev/null +++ b/arch/arm/mach-omap2/wd_timer.c @@ -0,0 +1,68 @@ +/* + * OMAP2+ MPU WD_TIMER-specific code + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include +#include +#include + +#include + +/* + * In order to avoid any assumptions from bootloader regarding WDT + * settings, WDT module is reset during init. This enables the watchdog + * timer. Hence it is required to disable the watchdog after the WDT reset + * during init. Otherwise the system would reboot as per the default + * watchdog timer registers settings. + */ +#define OMAP_WDT_WPS 0x34 +#define OMAP_WDT_SPR 0x48 + + +int omap2_wd_timer_disable(struct omap_hwmod *oh) +{ + void __iomem *base; + int ret; + + if (!oh) { + pr_err("%s: Could not look up wdtimer_hwmod\n", __func__); + return -EINVAL; + } + + base = omap_hwmod_get_mpu_rt_va(oh); + if (!base) { + pr_err("%s: Could not get the base address for %s\n", + oh->name, __func__); + return -EINVAL; + } + + /* Enable the clocks before accessing the WDT registers */ + ret = omap_hwmod_enable(oh); + if (ret) { + pr_err("%s: Could not enable clocks for %s\n", + oh->name, __func__); + return ret; + } + + /* sequence required to disable watchdog */ + __raw_writel(0xAAAA, base + OMAP_WDT_SPR); + while (__raw_readl(base + OMAP_WDT_WPS) & 0x10) + cpu_relax(); + + __raw_writel(0x5555, base + OMAP_WDT_SPR); + while (__raw_readl(base + OMAP_WDT_WPS) & 0x10) + cpu_relax(); + + ret = omap_hwmod_idle(oh); + if (ret) + pr_err("%s: Could not disable clocks for %s\n", + oh->name, __func__); + + return ret; +} + -- cgit v1.1