On Sat, Oct 11, 2014 at 12:12:01PM +0200, Johan Hovold wrote:

On Fri, Oct 10, 2014 at 01:02:31PM -0500, Felipe Balbi wrote:

quoted

Hi,

On Thu, Oct 09, 2014 at 09:06:30PM +0200, Johan Hovold wrote:

quoted

Make sure to restore local irq state when reading the timer/calendar
(TC) registers, so that omap_rtc_read_time() can be called with
interrupts disabled.

Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/rtc/rtc-omap.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
index 0ef016553a97..62e2e9a9887a 100644
--- a/drivers/rtc/rtc-omap.c
+++ b/drivers/rtc/rtc-omap.c

@@ -239,8 +239,10 @@ static void bcd2tm(struct rtc_time *tm)
 
 static int omap_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
+	unsigned long flags;
+
 	/* we don't report wday/yday/isdst ... */
-	local_irq_disable();
+	local_irq_save(flags);

you should really convert these to a real spin_lock_irq*(), that's
because local_irq* do not get re-written with RT patchset, so this
pretty much "breaks" RT.

The driver uses local_irq* throughout to guarantee registers are not
read or written during an update event.

In fact, at least on AM33xx, this is not even necessary when reading (as
opposed to writing) the TC registers, but I did not dare change that
without knowing how the legacy platforms work in this respect.

Do you suggest doing this conversion as part of, or on top of, this
series?

probably on top of is. Safer that way.

-- 
balbi
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