3.11.10.2 -stable review patch.  If anyone has any objections, please let me 
know.

------------------

From: Joel Fernandes <[email protected]>

commit 912e663127c5f700da6805ce21635dce703cb2cc upstream.

Enabling of Posted mode is seen to cause problems on dmtimer modules on AM33xx
(much like other OMAPs).  Reference discussions on forums [1] [2]. Earlier
patch solving this on other OMAPs [3].

For OMAP SoCs with this errata, the fix has been to not enable Posted mode.
However, on some SoCs (atleast AM33xx) which carry this errata, Posted mode
is enabled on reset. So we not only need to ignore enabling of the POSTED bit
when the timer is requested, but also disable Posted mode if errata is present.

[1] http://e2e.ti.com/support/arm/sitara_arm/f/791/t/285744.aspx
[2] http://e2e.ti.com/support/arm/sitara_arm/f/791/t/270632.aspx
[3] http://www.spinics.net/lists/linux-omap/msg81770.html

Reported-by: Russ Dill <[email protected]>
Cc: Santosh Shilimkar <[email protected]>
Signed-off-by: Joel Fernandes <[email protected]>
Signed-off-by: Tony Lindgren <[email protected]>
Signed-off-by: Luis Henriques <[email protected]>
---
 arch/arm/plat-omap/include/plat/dmtimer.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/arm/plat-omap/include/plat/dmtimer.h 
b/arch/arm/plat-omap/include/plat/dmtimer.h
index fb92abb..2861b15 100644
--- a/arch/arm/plat-omap/include/plat/dmtimer.h
+++ b/arch/arm/plat-omap/include/plat/dmtimer.h
@@ -336,8 +336,11 @@ static inline void __omap_dm_timer_enable_posted(struct 
omap_dm_timer *timer)
        if (timer->posted)
                return;
 
-       if (timer->errata & OMAP_TIMER_ERRATA_I103_I767)
+       if (timer->errata & OMAP_TIMER_ERRATA_I103_I767) {
+               timer->posted = OMAP_TIMER_NONPOSTED;
+               __omap_dm_timer_write(timer, OMAP_TIMER_IF_CTRL_REG, 0, 0);
                return;
+       }
 
        __omap_dm_timer_write(timer, OMAP_TIMER_IF_CTRL_REG,
                              OMAP_TIMER_CTRL_POSTED, 0);
-- 
1.8.3.2

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