[PATCH 05/10] ARM: dt: tegra: add bindings of power management configurations for PMC

Joseph Lo josephl at nvidia.com
Mon Mar 4 06:40:41 EST 2013


The PMC mostly controls the entry and exit of the system from different
sleep modes. Different platform or system may have different configurations.
The power management configurations of PMC is represented as some properties.
The system needs to define the properties when the system supports deep sleep
mode (i.e. suspend).

Signed-off-by: Joseph Lo <josephl at nvidia.com>
---
 .../bindings/arm/tegra/nvidia,tegra20-pmc.txt      | 45 +++++++++++++++++++++-
 1 file changed, 44 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
index b5846e2..4216c34 100644
--- a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
+++ b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
@@ -1,14 +1,49 @@
 NVIDIA Tegra Power Management Controller (PMC)
 
-Properties:
+The PMC block interacts with an external Power Management Unit. The PMC
+mostly controls the entry and exit of the system from different sleep
+modes. It provides power-gating controllers for SoC and CPU power-islands.
+
+Required properties:
 - name : Should be pmc
 - compatible : Should contain "nvidia,tegra<chip>-pmc".
 - reg : Offset and length of the register set for the device
+
+Optional properties:
 - nvidia,invert-interrupt : If present, inverts the PMU interrupt signal.
   The PMU is an external Power Management Unit, whose interrupt output
   signal is fed into the PMC. This signal is optionally inverted, and then
   fed into the ARM GIC. The PMC is not involved in the detection or
   handling of this interrupt signal, merely its inversion.
+- nvidia,suspend-mode : The suspend mode that the platform should use.
+  Valid valuse are 0, 1 and 2:
+  0 (LP0): CPU + Core voltage off and DRAM in self-refresh
+  1 (LP1): CPU vlotage off and DRAM in self-refresh
+  2 (LP2): CPU voltage off
+- nvidia,cpu-pwr-good-time : CPU power good time in uS. If not present, the
+  suspend function will be disabled as default.
+- nvidia,cpu-pwr-off-time : CPU power off time in uS. If not present, the
+  suspend function will be disabled as default.
+- nvidia,core-pwr-good-time : <Oscillator-stable-time Power-stable-time>
+  Core power good time in uS. If not present, the suspend function will
+  be disabled as default.
+- nvidia,core-pwr-off-time : Core power off time in uS. If not present, the
+  suspend function will be disabled as default.
+- nvidia,core-power-req-active-high : Boolean, core power request active-high
+- nvidia,sys-clock-req-active-high : Boolean, system clock request active-high
+- nvidia,combined-power-req : Boolean, combined power request for CPU & Core
+- nvidia,cpu-pwr-good-en : Boolean, CPU power good signal (from PMIC to PMC)
+			   is enabled.
+
+Required properties when nvidia,suspend-mode=<0>:
+- nvidia,lp0-vec : <start length> Starting address and length of LP0 vector
+  The LP0 vector contains the warm boot code that is executed by AVP when
+  resuming from the LP0 state. The AVP (Audio-Video Processor) is an ARM7
+  processor and always being the first boot processor when chip is power on
+  or resume from deep sleep mode. When the system is resumed from the deep
+  sleep mode, the warm boot code will restore some PLLs, clocks and then
+  bring up CPU0 for resuming the system. If the suspend mode is LP0, then
+  this property is must to have.
 
 Example:
 
@@ -16,4 +51,12 @@ pmc at 7000f400 {
 	compatible = "nvidia,tegra20-pmc";
 	reg = <0x7000e400 0x400>;
 	nvidia,invert-interrupt;
+	nvidia,suspend-mode = <1>;
+	nvidia,cpu-pwr-good-time = <2000>;
+	nvidia,cpu-pwr-off-time = <100>;
+	nvidia,core-pwr-good-ticks = <3845 3845>;
+	nvidia,core-pwr-off-ticks = <458>;
+	nvidia,core-power-req-active-high;
+	nvidia,sys-clock-req-active-high;
+	nvidia,lp0-vec = <0xbdffd000 0x2000>;
 };
-- 
1.8.1.1




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