On Tue, Jul 16 2019 at 08:47 -0600, Sudeep Holla wrote:
On Mon, May 13, 2019 at 09:22:59PM +0200, Ulf Hansson wrote:
From: Lina Iyer <lina.iyer@xxxxxxxxxx>
In the hierarchical layout, we are creating power domains around each CPU
and describes the idle states for them inside the power domain provider
node. Note that, the CPU's idle states still needs to be compatible with
"arm,idle-state".
Furthermore, represent the CPU cluster as a separate master power domain,
powering the CPU's power domains. The cluster node, contains the idle
states for the cluster and each idle state needs to be compatible with the
"domain-idle-state".
If the running platform is using a PSCI FW that supports the OS initiated
CPU suspend mode, which likely should be the case unless the PSCI FW is
very old, this change triggers the PSCI driver to enable it.
Cc: Andy Gross <andy.gross@xxxxxxxxxx>
Cc: David Brown <david.brown@xxxxxxxxxx>
Signed-off-by: Lina Iyer <lina.iyer@xxxxxxxxxx>
Co-developed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
---
[...]
@@ -166,12 +170,57 @@
min-residency-us = <2000>;
local-timer-stop;
};
+
+ CLUSTER_RET: cluster-retention {
+ compatible = "domain-idle-state";
+ arm,psci-suspend-param = <0x1000010>;
+ entry-latency-us = <500>;
+ exit-latency-us = <500>;
+ min-residency-us = <2000>;
+ };
+
+ CLUSTER_PWRDN: cluster-gdhs {
+ compatible = "domain-idle-state";
+ arm,psci-suspend-param = <0x1000030>;
+ entry-latency-us = <2000>;
+ exit-latency-us = <2000>;
+ min-residency-us = <6000>;
+ };
};
};
I was trying to understand the composition of composite state parameters
in this series and that made me look at these DT examples.
This was meant to depict a hierarchical state format for OSI.
What format does the above platform use ? I tried matching them to
both original as well as extended format and I fail to understand.
Assuming original format:
State power_state PowerLevel StateType StateID
SPC 0x40000002 0(core) 0(Retention) 0x2 (Res0 b[29]=1?)
CLUSTER_RET 0x1000010 1(clusters) 0(Retention) 0x10
CLUSTER_PWRDN 0x1000030 1(clusters) 0(Retention?) 0x30
Now extended format:
State power_state StateType StateID
SPC 0x40000002 0(Retention) 0x40000002 (Res0 b[29]=1?)
CLUSTER_RET 0x1000010 0(Retention) 0x1000010
The composite state would comprise of CPU state and Cluster state.
So for the last CPU entering idle -
(CLUSTER_RET | SPC)
0x41000012
CLUSTER_PWRDN 0x1000030 0(Retention?) 0x1000030
(CLUSTER_PWRDN | SPC)
0x41000032
Hope this helps.
Lina
