[v2,05/15] dt-bindings: devfreq: rk3399_dmc: Add more disable-freq properties

Commit Message

Brian Norris Jan. 27, 2022, 11:07 p.m. UTC

DDR DVFS tuning has found that several power-saving features don't have
good tradeoffs at higher frequencies -- at higher frequencies, we'll see
glitches or other errors. Provide tuning controls so these can be
disabled at higher OPPs, and left active only at the lower ones.

Signed-off-by: Brian Norris <[e-mail]>
---

Changes in v2:
 - hyphens, not underscores
 - *-hz units, and drop the types definition

 .../bindings/devfreq/rk3399_dmc.yaml          | 37 +++++++++++++++++++
 1 file changed, 37 insertions(+)

Comments

Rob Herring (Arm) Feb. 9, 2022, 8:29 p.m. UTC | #1

On Thu, 27 Jan 2022 15:07:16 -0800, Brian Norris wrote:
> DDR DVFS tuning has found that several power-saving features don't have
> good tradeoffs at higher frequencies -- at higher frequencies, we'll see
> glitches or other errors. Provide tuning controls so these can be
> disabled at higher OPPs, and left active only at the lower ones.
> 
> Signed-off-by: Brian Norris <[e-mail]>
> ---
> 
> Changes in v2:
>  - hyphens, not underscores
>  - *-hz units, and drop the types definition
> 
>  .../bindings/devfreq/rk3399_dmc.yaml          | 37 +++++++++++++++++++
>  1 file changed, 37 insertions(+)
> 

Reviewed-by: Rob Herring <[e-mail]>

Patch

diff --git a/Documentation/devicetree/bindings/devfreq/rk3399_dmc.yaml b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.yaml
index 8786b7fa9b28..afa058c52c0b 100644
--- a/Documentation/devicetree/bindings/devfreq/rk3399_dmc.yaml
+++ b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.yaml
@@ -299,6 +299,38 @@  properties:
       self-refresh mode. The controller, pi, PHY and DRAM clock will be gated
       if bus is idle for standby_idle nanoseconds.
 
+  rockchip,pd-idle-dis-freq-hz:
+    description:
+      Defines the power-down idle disable frequency in Hz. When the DDR
+      frequency is greater than pd-idle-dis-freq, power-down idle is disabled.
+      See also rockchip,pd-idle-ns.
+
+  rockchip,sr-idle-dis-freq-hz:
+    description:
+      Defines the self-refresh idle disable frequency in Hz. When the DDR
+      frequency is greater than sr-idle-dis-freq, self-refresh idle is
+      disabled. See also rockchip,sr-idle-ns.
+
+  rockchip,sr-mc-gate-idle-dis-freq-hz:
+    description:
+      Defines the self-refresh and memory-controller clock gating disable
+      frequency in Hz. When the DDR frequency is greater than
+      sr-mc-gate-idle-dis-freq, the clock will not be gated when idle. See also
+      rockchip,sr-mc-gate-idle-ns.
+
+  rockchip,srpd-lite-idle-dis-freq-hz:
+    description:
+      Defines the self-refresh power down idle disable frequency in Hz. When
+      the DDR frequency is greater than srpd-lite-idle-dis-freq, memory will
+      not be placed into self-refresh power down mode when idle. See also
+      rockchip,srpd-lite-idle-ns.
+
+  rockchip,standby-idle-dis-freq-hz:
+    description:
+      Defines the standby idle disable frequency in Hz. When the DDR frequency
+      is greater than standby-idle-dis-freq, standby idle is disabled. See also
+      rockchip,standby-idle-ns.
+
 required:
   - compatible
   - devfreq-events
@@ -330,4 +362,9 @@  examples:
       rockchip,ddr3_odt_dis_freq = <333000000>;
       rockchip,lpddr3_odt_dis_freq = <333000000>;
       rockchip,lpddr4_odt_dis_freq = <333000000>;
+      rockchip,pd-idle-dis-freq-hz = <1000000000>;
+      rockchip,sr-idle-dis-freq-hz = <1000000000>;
+      rockchip,sr-mc-gate-idle-dis-freq-hz = <1000000000>;
+      rockchip,srpd-lite-idle-dis-freq-hz = <0>;
+      rockchip,standby-idle-dis-freq-hz = <928000000>;
     };