Blackfin RTC Driver: dont let RTC programming in bootloaders randomly cause ~5 second boot delays
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-bfin.c b/drivers/rtc/rtc-bfin.c
index 9d2da1c..34439ce 100644
--- a/drivers/rtc/rtc-bfin.c
+++ b/drivers/rtc/rtc-bfin.c
@@ -363,6 +363,7 @@
struct bfin_rtc *rtc;
struct device *dev = &pdev->dev;
int ret = 0;
+ unsigned long timeout;
dev_dbg_stamp(dev);
@@ -377,6 +378,13 @@
ret = request_irq(IRQ_RTC, bfin_rtc_interrupt, IRQF_SHARED, pdev->name, dev);
if (unlikely(ret))
goto err;
+ /* sometimes the bootloader touched things, but the write complete was not
+ * enabled, so let's just do a quick timeout here since the IRQ will not fire ...
+ */
+ timeout = jiffies + HZ;
+ while (bfin_read_RTC_ISTAT() & RTC_ISTAT_WRITE_PENDING)
+ if (time_after(jiffies, timeout))
+ break;
bfin_rtc_reset(dev, RTC_ISTAT_WRITE_COMPLETE);
bfin_write_RTC_SWCNT(0);