diff options
Diffstat (limited to 'arch/arm/mach-omap2/wd_timer.c')
| -rw-r--r-- | arch/arm/mach-omap2/wd_timer.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/wd_timer.c b/arch/arm/mach-omap2/wd_timer.c index 4067669d96c..b2f1c67043a 100644 --- a/arch/arm/mach-omap2/wd_timer.c +++ b/arch/arm/mach-omap2/wd_timer.c @@ -14,6 +14,7 @@ #include <plat/omap_hwmod.h> #include "wd_timer.h" +#include "common.h" /* * In order to avoid any assumptions from bootloader regarding WDT @@ -25,6 +26,8 @@ #define OMAP_WDT_WPS 0x34 #define OMAP_WDT_SPR 0x48 +/* Maximum microseconds to wait for OMAP module to softreset */ +#define MAX_MODULE_SOFTRESET_WAIT 10000 int omap2_wd_timer_disable(struct omap_hwmod *oh) { @@ -54,3 +57,45 @@ int omap2_wd_timer_disable(struct omap_hwmod *oh) return 0; } +/** + * omap2_wdtimer_reset - reset and disable the WDTIMER IP block + * @oh: struct omap_hwmod * + * + * After the WDTIMER IP blocks are reset on OMAP2/3, we must also take + * care to execute the special watchdog disable sequence. This is + * because the watchdog is re-armed upon OCP softreset. (On OMAP4, + * this behavior was apparently changed and the watchdog is no longer + * re-armed after an OCP soft-reset.) Returns -ETIMEDOUT if the reset + * did not complete, or 0 upon success. + * + * XXX Most of this code should be moved to the omap_hwmod.c layer + * during a normal merge window. omap_hwmod_softreset() should be + * renamed to omap_hwmod_set_ocp_softreset(), and omap_hwmod_softreset() + * should call the hwmod _ocp_softreset() code. + */ +int omap2_wd_timer_reset(struct omap_hwmod *oh) +{ + int c = 0; + + /* Write to the SOFTRESET bit */ + omap_hwmod_softreset(oh); + + /* Poll on RESETDONE bit */ + omap_test_timeout((omap_hwmod_read(oh, + oh->class->sysc->syss_offs) + & SYSS_RESETDONE_MASK), + MAX_MODULE_SOFTRESET_WAIT, c); + + if (oh->class->sysc->srst_udelay) + udelay(oh->class->sysc->srst_udelay); + + if (c == MAX_MODULE_SOFTRESET_WAIT) + pr_warning("%s: %s: softreset failed (waited %d usec)\n", + __func__, oh->name, MAX_MODULE_SOFTRESET_WAIT); + else + pr_debug("%s: %s: softreset in %d usec\n", __func__, + oh->name, c); + + return (c == MAX_MODULE_SOFTRESET_WAIT) ? -ETIMEDOUT : + omap2_wd_timer_disable(oh); +} |