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>
Reviewed-by: Rob Herring <robh at kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski at canonical.com>
---
(no changes since v3)
Changes in v3:
* Add Reviewed-by
Changes in v2:
* hyphens, not underscores
* *-hz units, and drop the types definition
.../rockchip,rk3399-dmc.yaml | 37 +++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/Documentation/devicetree/bindings/memory-controllers/rockchip,rk3399-dmc.yaml b/Documentation/devicetree/bindings/memory-controllers/rockchip,rk3399-dmc.yaml
index 5228a32b5962..fb4920397d08 100644
--- a/Documentation/devicetree/bindings/memory-controllers/rockchip,rk3399-dmc.yaml
+++ b/Documentation/devicetree/bindings/memory-controllers/rockchip,rk3399-dmc.yaml
@@ -313,6 +313,38 @@ 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
@@ -344,4 +376,9 @@ 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>;
};
--
2.35.1.616.g0bdcbb4464-goog