diff options
Diffstat (limited to 'drivers/watchdog/rti_wdt.c')
| -rw-r--r-- | drivers/watchdog/rti_wdt.c | 36 |
1 files changed, 15 insertions, 21 deletions
diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c index 859ef121886d..d4850be421ca 100644 --- a/drivers/watchdog/rti_wdt.c +++ b/drivers/watchdog/rti_wdt.c @@ -52,6 +52,8 @@ #define DWDST BIT(1) +#define MAX_HW_ERROR 250 + static int heartbeat = DEFAULT_HEARTBEAT; /* @@ -90,7 +92,7 @@ static int rti_wdt_start(struct watchdog_device *wdd) * to be 50% or less than that; we obviouly want to configure the open * window as large as possible so we select the 50% option. */ - wdd->min_hw_heartbeat_ms = 550 * wdd->timeout; + wdd->min_hw_heartbeat_ms = 520 * wdd->timeout + MAX_HW_ERROR; /* Generate NMI when wdt expires */ writel_relaxed(RTIWWDRX_NMI, wdt->base + RTIWWDRXCTRL); @@ -124,33 +126,33 @@ static int rti_wdt_setup_hw_hb(struct watchdog_device *wdd, u32 wsize) * be petted during the open window; not too early or not too late. * The HW configuration options only allow for the open window size * to be 50% or less than that. - * To avoid any glitches, we accommodate 5% safety margin, with the - * exception of open window size < 10%. + * To avoid any glitches, we accommodate 2% + max hardware error + * safety margin. */ switch (wsize) { case RTIWWDSIZE_50P: - /* 50% open window => 55% min heartbeat */ - wdd->min_hw_heartbeat_ms = 550 * heartbeat; + /* 50% open window => 52% min heartbeat */ + wdd->min_hw_heartbeat_ms = 520 * heartbeat + MAX_HW_ERROR; break; case RTIWWDSIZE_25P: - /* 25% open window => 80% min heartbeat */ - wdd->min_hw_heartbeat_ms = 800 * heartbeat; + /* 25% open window => 77% min heartbeat */ + wdd->min_hw_heartbeat_ms = 770 * heartbeat + MAX_HW_ERROR; break; case RTIWWDSIZE_12P5: - /* 12.5% open window => 92.5% min heartbeat */ - wdd->min_hw_heartbeat_ms = 925 * heartbeat; + /* 12.5% open window => 89.5% min heartbeat */ + wdd->min_hw_heartbeat_ms = 895 * heartbeat + MAX_HW_ERROR; break; case RTIWWDSIZE_6P25: - /* 6.5% open window => 96.5% min heartbeat */ - wdd->min_hw_heartbeat_ms = 965 * heartbeat; + /* 6.5% open window => 95.5% min heartbeat */ + wdd->min_hw_heartbeat_ms = 955 * heartbeat + MAX_HW_ERROR; break; case RTIWWDSIZE_3P125: - /* 3.125% open window => 97.9% min heartbeat */ - wdd->min_hw_heartbeat_ms = 979 * heartbeat; + /* 3.125% open window => 98.9% min heartbeat */ + wdd->min_hw_heartbeat_ms = 989 * heartbeat + MAX_HW_ERROR; break; default: @@ -223,14 +225,6 @@ static int rti_wdt_probe(struct platform_device *pdev) return -EINVAL; } - /* - * If watchdog is running at 32k clock, it is not accurate. - * Adjust frequency down in this case so that we don't pet - * the watchdog too often. - */ - if (wdt->freq < 32768) - wdt->freq = wdt->freq * 9 / 10; - pm_runtime_enable(dev); ret = pm_runtime_resume_and_get(dev); if (ret < 0) { |