ARM: dts: sunxi: A20-OlinuXino-Lime2 raise dcdc2 lower voltage limit
Subsystems (2)
The Lime2 is not stable if the cpu core voltage is reduced below 1v. To prevent any problems when operating points are enabled, raise the pmic dcdc2 lower voltage limit to 1v.
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Maxime, I realise the axp209 nodes will probably end up abstracted somewhat differently once all of the patches Chen-Yu posted are reviewed and picked up and I can redo the lime2 dts to fit once that's done.
For now, the lime2 dts defines the full axp209 node itself including all of the regulators, so if the lowest opp with the 0.9v setting is enabled this will cause problems.
Up to you if you want to take this patch now or we wait until the axp209.dtsi lands and refactor the lime2 dts appropriately then.
arch/arm/boot/dts/sun7i-a20-olinuxino-lime2.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
arch/arm/boot/dts/sun7i-a20-olinuxino-lime2.dts +1 -1
@@ -159,7 +159,7 @@ }; vdd_cpu: dcdc2 { - regulator-min-microvolt = <700000>; + regulator-min-microvolt = <1000000>; regulator-max-microvolt = <2275000>; regulator-always-on; };
Signature · 1 line
2.1.3
Quoted 25 lines · Iain Paton
The Lime2 is not stable if the cpu core voltage is reduced below 1v. To prevent any problems when operating points are enabled, raise the pmic dcdc2 lower voltage limit to 1v.
Signed-off-by Iain Paton <[email protected]>---
Maxime, I realise the axp209 nodes will probably end up abstracted somewhat differently once all of the patches Chen-Yu posted are reviewed and picked up and I can redo the lime2 dts to fit once that's done.
For now, the lime2 dts defines the full axp209 node itself including all of the regulators, so if the lowest opp with the 0.9v setting is enabled this will cause problems.Up to you if you want to take this patch now or we wait until the
axp209.dtsilands and refactor the lime2 dts appropriately then.arch/arm/boot/dts/sun7i-a20-olinuxino-lime2.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)arch/arm/boot/dts/sun7i-a20-olinuxino-lime2.dts +0
-0
arch/arm/boot/dts/sun7i-a20-olinuxino-lime2.dts line 163
Quoted 6 lines
arch/arm/boot/dts/sun7i-a20-olinuxino-lime2.dts +1
-1@@ -159,7 +159,7 @@ }; vdd_cpu: dcdc2 { - regulator-min-microvolt = <700000>; + regulator-min-microvolt = <1000000>; regulator-max-microvolt = <2275000>;
You should lower the maximum voltage as well, either in this patch or when you redo all the regulators. AFAIK the SoC certainly cannot take up to 2.275V. The regulator nodes are supposed to say what the board can handle.
ChenYu
Quoted 5 lines
arch/arm/boot/dts/sun7i-a20-olinuxino-lime2.dts +0
-1regulator-always-on; }; --2.1.3
Quoted 4 lines · wens Tsai
You should lower the maximum voltage as well, either in this patch or when you redo all the regulators. AFAIK the SoC certainly cannot take up to 2.275V. The regulator nodes are supposed to say what the board can handle.
Yes, I suspect several of them are not currently sensible. I just used the limits from the pmic datasheet at the time as there were no other boards with axp209 regulator defined, no fex file for the lime2 etc.
I likely would have sent a full respin based on your patches, but as only bits have been applied it seemed better to do this minimal one and fix the rest properly later.
I can do a couple of the other Olimex boards that I have available to test while I'm doing it.
Iain
Quoted 11 lines · Iain Paton
Quoted 4 lines · wens Tsai
You should lower the maximum voltage as well, either in this patch or when you redo all the regulators. AFAIK the SoC certainly cannot take up to 2.275V. The regulator nodes are supposed to say what the board can handle.
Yes, I suspect several of them are not currently sensible. I just used the limits from the pmic datasheet at the time as there were no other boards with axp209 regulator defined, no fex file for the lime2 etc.
Quoted 5 lines
I likely would have sent a full respin based on your patches, but as only bits have been applied it seemed better to do this minimal one and fix the rest properly later.
I can do a couple of the other Olimex boards that I have available to test while I'm doing it.
All the meaningful patches should have been merged by now, so it would be good if you could resend this with the proper limits for all the regulators enabled.
Thanks!
Maxime
Signature · 10 lines
Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20150112/6e083860/attachment.sig>