[PATCH 04/10] dt-bindings: devfreq: rk3399_dmc: Add more disable-freq properties

Brian Norris briannorris at chromium.org
Fri Jan 7 15:53:14 PST 2022


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 <briannorris at chromium.org>
---

 .../bindings/devfreq/rk3399_dmc.yaml          | 42 +++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/Documentation/devicetree/bindings/devfreq/rk3399_dmc.yaml b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.yaml
index 2c871c57fd97..357d07c5a3df 100644
--- a/Documentation/devicetree/bindings/devfreq/rk3399_dmc.yaml
+++ b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.yaml
@@ -271,6 +271,43 @@ properties:
       When the DRAM type is LPDDR4, this parameter defines the PHY side ODT
       strength. Default value is 60.
 
+  rockchip,pd_idle_dis_freq:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    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.
+
+  rockchip,sr_idle_dis_freq:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    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.
+
+  rockchip,sr_mc_gate_idle_dis_freq:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    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.
+
+  rockchip,srpd_lite_idle_dis_freq:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    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.
+
+  rockchip,standby_idle_dis_freq:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    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.
+
 additionalProperties: false
 
 examples:
@@ -294,4 +331,9 @@ examples:
       rockchip,ddr3_odt_dis_freq = <333000000>;
       rockchip,lpddr3_odt_dis_freq = <333000000>;
       rockchip,lpddr4_odt_dis_freq = <333000000>;
+      rockchip,pd_idle_dis_freq = <1000000000>;
+      rockchip,sr_idle_dis_freq = <1000000000>;
+      rockchip,sr_mc_gate_idle_dis_freq = <1000000000>;
+      rockchip,srpd_lite_idle_dis_freq = <0>;
+      rockchip,standby_idle_dis_freq = <928000000>;
     };
-- 
2.34.1.575.g55b058a8bb-goog




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