ARM: dts: sunxi: Fix cpufreq instabilities
Subsystems (2)
v2 cover ARM: dts: sunxi: Fix cpufreq instabilities
Hi Maxime,
Here's v2 of the sunxi cpufreq dts fixes, rebased onto v4.0-rc5. I assume you'll fix up the merge conflicts with 4.1 stuff?
The first patch limits the Olimex A10-Lime to 912MHz, as a few people reported on IRC that it was unstable at 1008MHz.
The second patch removes the overclocking settings from sun[457]i dts, so all the boards will be stable, regardless of whether regulators were added or not.
I would like to revisit this after the new OPP bindings are merged and support added to cpufreq-dt.
Changes since v1:
- Added sun4i dts fixes
- Corrected A10-Lime settings to match sun4i
Regards
ChenYu
Chen-Yu Tsai (2):
ARM: dts: sun4i: a10-lime: Override and remove 1008MHz OPP setting
ARM: dts: sunxi: Remove overclocked/overvoltaged OPP
arch/arm/boot/dts/sun4i-a10-olinuxino-lime.dts | 16 ++++++++++++++++ arch/arm/boot/dts/sun4i-a10.dtsi | 3 +-- arch/arm/boot/dts/sun5i-a13.dtsi | 3 +-- arch/arm/boot/dts/sun7i-a20.dtsi | 3 +-- 4 files changed, 19 insertions(+), 6 deletions(-)
Signature · 1 line
2.1.4
PATCH RESEND v2 1/2 ARM: dts: sun4i: a10-lime: Override and remove 1008MHz OPP setting
The Olimex A10-Lime is known to be unstable when running at 1008MHz.
--- arch/arm/boot/dts/sun4i-a10-olinuxino-lime.dts | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
arch/arm/boot/dts/sun4i-a10-olinuxino-lime.dts +16 -0
@@ -56,6 +56,22 @@ model = "Olimex A10-OLinuXino-LIME"; compatible = "olimex,a10-olinuxino-lime", "allwinner,sun4i-a10"; + cpus { + cpu0: cpu at 0 { + /* + * The A10-Lime is known to be unstable + * when running at 1008 MHz + */ + operating-points = < + /* kHz uV */ + 912000 1350000 + 864000 1300000 + 624000 1250000 + >; + cooling-max-level = <2>; + }; + }; + soc at 01c00000 { emac: ethernet at 01c0b000 { pinctrl-names = "default";
Signature · 1 line
2.1.4
PATCH RESEND v2 1/2 ARM: dts: sun4i: a10-lime: Override and remove 1008MHz OPP setting
arch/arm/boot/dts/sun4i-a10-olinuxino-lime.dts line 68
Quoted 6 lines · Chen-Yu Tsai
The Olimex A10-Lime is known to be unstable when running at 1008MHz.
arch/arm/boot/dts/sun4i-a10-olinuxino-lime.dts +4
-0+ operating-points = < + /* kHz uV */ + 912000 1350000 + 864000 1300000
If we're dropping the top speed to 912 in the kernel, should we do the same in u-boot?
I was already planning on sending a patch to add the 912MHz setting to u-boot due to sun7i requesting CONFIG_CLK_FULL_SPEED of 912 but getting overclocked to 960 instead. I can easily do this at the same time.
Rgds,
Iain
PATCH RESEND v2 2/2 ARM: dts: sunxi: Remove overclocked/overvoltaged OPP
In reply to Chen-Yu TsaiWithout proper regulator support for individual boards, it is dangerous to have overclocked/overvoltaged OPPs in the list. Cpufreq will increase the frequency without the accompanying voltage increase, resulting in an unstable system.
Remove them for now. We can revisit them with the new version of OPP bindings, which support boost settings and frequency ranges, among other things.
--- arch/arm/boot/dts/sun4i-a10.dtsi | 3 +-- arch/arm/boot/dts/sun5i-a13.dtsi | 3 +-- arch/arm/boot/dts/sun7i-a20.dtsi | 3 +-- 3 files changed, 3 insertions(+), 6 deletions(-)
arch/arm/boot/dts/sun4i-a10.dtsi +1 -2
@@ -75,7 +75,6 @@ clock-latency = <244144>; /* 8 32k periods */ operating-points = < /* kHz uV */ - 1056000 1500000 1008000 1400000 912000 1350000 864000 1300000
@@ -83,7 +82,7 @@ >; #cooling-cells = <2>; cooling-min-level = <0>; - cooling-max-level = <4>; + cooling-max-level = <3>; }; };
arch/arm/boot/dts/sun5i-a13.dtsi +1 -2
@@ -47,7 +47,6 @@ clock-latency = <244144>; /* 8 32k periods */ operating-points = < /* kHz uV */ - 1104000 1500000 1008000 1400000 912000 1350000 864000 1300000
@@ -57,7 +56,7 @@ >; #cooling-cells = <2>; cooling-min-level = <0>; - cooling-max-level = <6>; + cooling-max-level = <5>; }; };
arch/arm/boot/dts/sun7i-a20.dtsi +1 -2
@@ -105,7 +105,6 @@ clock-latency = <244144>; /* 8 32k periods */ operating-points = < /* kHz uV */ - 1008000 1450000 960000 1400000 912000 1400000 864000 1300000
@@ -116,7 +115,7 @@ >; #cooling-cells = <2>; cooling-min-level = <0>; - cooling-max-level = <7>; + cooling-max-level = <6>; }; cpu at 1 {
Signature · 1 line
2.1.4
Maxime Ripard
Appliedv2 cover ARM: dts: sunxi: Fix cpufreq instabilities
In reply to Chen-Yu TsaiQuoted 8 lines · Chen-Yu Tsai
Hi Maxime,
Here's v2 of the sunxi cpufreq dts fixes, rebased onto v4.0-rc5. I assume you'll fix up the merge conflicts with 4.1 stuff?
The first patch limits the Olimex A10-Lime to 912MHz, as a few people reported on IRC that it was unstable at 1008MHz.
Quoted 6 lines
The second patch removes the overclocking settings from sun[457]i dts, so all the boards will be stable, regardless of whether regulators were added or not.
I would like to revisit this after the new OPP bindings are merged and support added to cpufreq-dt.
Applied both, 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/20150324/0016420b/attachment.sig>