diff mbox series

[v6,01/10] dt-bindings: cpufreq: mediatek: Add MediaTek CCI property

Message ID 20220505115226.20130-2-rex-bc.chen@mediatek.com
State Accepted
Commit 818c8321d8def50971188b8b33ef2a43ca1e2511
Headers show
Series cpufreq: mediatek: Cleanup and support MT8183 and MT8186 | expand

Commit Message

Rex-BC Chen (陳柏辰) May 5, 2022, 11:52 a.m. UTC
MediaTek Cache Coherent Interconnect (CCI) uses software devfreq module
for scaling clock frequency and adjust voltage.
The phandle could be linked between CPU and MediaTek CCI for some
MediaTek SoCs, like MT8183 and MT8186.

The reason we need the link status between cpufreq and MediaTek cci is
cpufreq and mediatek cci could share the same regulator in some MediaTek
SoCs. Therefore, to prevent the issue of high frequency and low voltage,
we need to use this to make sure mediatek cci is ready.

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
 .../devicetree/bindings/cpufreq/cpufreq-mediatek.txt       | 7 +++++++
 1 file changed, 7 insertions(+)

Comments

Rob Herring May 11, 2022, 2:37 p.m. UTC | #1
On Thu, 05 May 2022 19:52:17 +0800, Rex-BC Chen wrote:
> MediaTek Cache Coherent Interconnect (CCI) uses software devfreq module
> for scaling clock frequency and adjust voltage.
> The phandle could be linked between CPU and MediaTek CCI for some
> MediaTek SoCs, like MT8183 and MT8186.
> 
> The reason we need the link status between cpufreq and MediaTek cci is
> cpufreq and mediatek cci could share the same regulator in some MediaTek
> SoCs. Therefore, to prevent the issue of high frequency and low voltage,
> we need to use this to make sure mediatek cci is ready.
> 
> Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> ---
>  .../devicetree/bindings/cpufreq/cpufreq-mediatek.txt       | 7 +++++++
>  1 file changed, 7 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-mediatek.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-mediatek.txt
index b8233ec91d3d..e0a4ba599abc 100644
--- a/Documentation/devicetree/bindings/cpufreq/cpufreq-mediatek.txt
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-mediatek.txt
@@ -20,6 +20,13 @@  Optional properties:
 	       Vsram to fit SoC specific needs. When absent, the voltage scaling
 	       flow is handled by hardware, hence no software "voltage tracking" is
 	       needed.
+- mediatek,cci:
+	Used to confirm the link status between cpufreq and mediatek cci. Because
+	cpufreq and mediatek cci could share the same regulator in some MediaTek SoCs.
+	To prevent the issue of high frequency and low voltage, we need to use this
+	property to make sure mediatek cci is ready.
+	For details of mediatek cci, please refer to
+	Documentation/devicetree/bindings/interconnect/mediatek,cci.yaml
 - #cooling-cells:
 	For details, please refer to
 	Documentation/devicetree/bindings/thermal/thermal-cooling-devices.yaml