Re: [PATCH 8/9] ARM: dts: sun7i: bananapi-m1-plus: Add PMIC regulators and OPPs for cpufreq

Hi,

On Sat, Jul 9, 2016 at 4:18 PM, Maxime Ripard
[off-list ref] wrote:

Hi,

On Wed, Jul 06, 2016 at 05:10:49PM +0800, Chen-Yu Tsai wrote:

quoted

The Bananapi M1+, like other Allwinner A20 based boards, uses the AXP209
PMIC to supply its power. The vendor FEX file's DVFS table suggests the
board's CPU power rail has a voltage drop of 25 ~ 50 mV.

Add the PMIC regulator nodes and copy the DVFS table from the FEX file.

Signed-off-by: Chen-Yu Tsai <redacted>
---
 arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts | 48 ++++++++++++++++++++++--
 1 file changed, 44 insertions(+), 4 deletions(-)

diff --git a/arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts b/arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts
index ba5bca0fe997..7bb418bd1b6e 100644
--- a/arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts
+++ b/arch/arm/boot/dts/sun7i-a20-bananapi-m1-plus.dts

@@ -105,6 +105,22 @@
      status = "okay";
 };

+&cpu0 {
+     cpu-supply = <&reg_dcdc2>;
+
+     /* The custom DVFS table suggests a voltage drop of 25 ~ 50 mV */
+     operating-points = <
+             /* kHz    uV */
+             1080000 1450000
+             912000  1425000
+             864000  1350000
+             720000  1250000
+             528000  1150000
+             312000  1100000
+             144000  1050000
+             >;
+};
+

We've always tried to not use all the non-sense OPPs coming from the
FEX files. Have you experienced any issues with the default ones?

I'll find some time to run a stress test on it.

The other patches have been queued either for 4.8 as fixes, or 4.9.

Thanks!

ChenYu

Thanks!
Maxime

--
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com