[PATCH AUTOSEL 4.19 24/38] ARM: dts: ls1021a: output PPS signal on FIPER2

Sasha Levin
2020-08-21T16:23:11Z

From: Yangbo Lu <yangbo.lu@nxp.com>

[ Upstream commit 5656bb3857c4904d1dec6e1b8f876c1c0337274e ]

The timer fixed interval period pulse generator register
is used to generate periodic pulses. The down count
register loads the value programmed in the fixed period
interval (FIPER). At every tick of the timer accumulator
overflow, the counter decrements by the value of
TMR_CTRL[TCLK_PERIOD]. It generates a pulse when the down
counter value reaches zero. It reloads the down counter
in the cycle following a pulse.

To use the TMR_FIPER register to generate desired periodic
pulses. The value should programmed is,
desired_period - tclk_period

Current tmr-fiper2 value is to generate 100us periodic pulses.
(But the value should have been 99995, not 99990. The tclk_period is 5.)
This patch is to generate 1 second periodic pulses with value
999999995 programmed which is more desired by user.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/arm/boot/dts/ls1021a.dtsi | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/ls1021a.dtsi b/arch/arm/boot/dts/ls1021a.dtsi
index 074b4ec520c63..d18c043264440 100644
--- a/arch/arm/boot/dts/ls1021a.dtsi
+++ b/arch/arm/boot/dts/ls1021a.dtsi
@@ -609,7 +609,7 @@ ptp_clock@2d10e00 {
fsl,tmr-prsc = <2>;
fsl,tmr-add = <0xaaaaaaab>;
fsl,tmr-fiper1 = <999999995>;
- fsl,tmr-fiper2 = <99990>;
+ fsl,tmr-fiper2 = <999999995>;
fsl,max-adj = <499999999>;
};

--
2.25.1