projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 81fbc5ef PW |
1 | /* |
| 2 | * OMAP2+ MPU WD_TIMER-specific code | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or modify | |
| 5 | * it under the terms of the GNU General Public License as published by | |
| 6 | * the Free Software Foundation; either version 2 of the License, or | |
| 7 | * (at your option) any later version. | |
| 8 | */ | |
| 9 | ||
| 10 | #include <linux/kernel.h> | |
| 11 | #include <linux/io.h> | |
| 12 | #include <linux/err.h> | |
| 13 | ||
| 14 | #include <plat/omap_hwmod.h> | |
| 15 | ||
| 16 | /* | |
| 17 | * In order to avoid any assumptions from bootloader regarding WDT | |
| 18 | * settings, WDT module is reset during init. This enables the watchdog | |
| 19 | * timer. Hence it is required to disable the watchdog after the WDT reset | |
| 20 | * during init. Otherwise the system would reboot as per the default | |
| 21 | * watchdog timer registers settings. | |
| 22 | */ | |
| 23 | #define OMAP_WDT_WPS 0x34 | |
| 24 | #define OMAP_WDT_SPR 0x48 | |
| 25 | ||
| 26 | ||
| 27 | int omap2_wd_timer_disable(struct omap_hwmod *oh) | |
| 28 | { | |
| 29 | void __iomem *base; | |
| 81fbc5ef PW |
30 | |
| 31 | if (!oh) { | |
| 32 | pr_err("%s: Could not look up wdtimer_hwmod\n", __func__); | |
| 33 | return -EINVAL; | |
| 34 | } | |
| 35 | ||
| 36 | base = omap_hwmod_get_mpu_rt_va(oh); | |
| 37 | if (!base) { | |
| 38 | pr_err("%s: Could not get the base address for %s\n", | |
| 39 | oh->name, __func__); | |
| 40 | return -EINVAL; | |
| 41 | } | |
| 42 | ||
| 81fbc5ef PW |
43 | /* sequence required to disable watchdog */ |
| 44 | __raw_writel(0xAAAA, base + OMAP_WDT_SPR); | |
| 45 | while (__raw_readl(base + OMAP_WDT_WPS) & 0x10) | |
| 46 | cpu_relax(); | |
| 47 | ||
| 48 | __raw_writel(0x5555, base + OMAP_WDT_SPR); | |
| 49 | while (__raw_readl(base + OMAP_WDT_WPS) & 0x10) | |
| 50 | cpu_relax(); | |
| 51 | ||
| ff2516fb | 52 | return 0; |
| 81fbc5ef PW |
53 | } |
| 54 |