commit b5d7222f549d6e60742b139155f9cf0f55d4f8c1
author Jonathan Doman <jonathan.doman@intel.com> Thu Jan 11 14:20:13 2024 -0800
committer Jonathan Doman <jonathan.doman@intel.com> Thu Jan 11 19:14:06 2024 -0800
tree bc5e5e840299410ad3899ed9e919162dee93899b
parent 117671edb829f9495cbb725a2f38e62389d3fe64

sst: Don't always wake idle CPU

Some parts of SST are important (initial discovery, appliedConfig
change) and should use wake-on-PECI to ensure success even if the CPU is
in an idle PkgC state. Other parts are not important enough to justify
increasing the CPU power draw. Add a WakePolicy parameter to the
SSTInterface infrastructure to use a different policy in different
contexts.

Change-Id: I91435cc0357ab60ca4656e1bc51286e046ae3809
Signed-off-by: Jonathan Doman <jonathan.doman@intel.com>

src/sst_mailbox.cpp

diff --git a/src/sst_mailbox.cpp b/src/sst_mailbox.cpp
index 2627894..b086c55 100644
--- a/src/sst_mailbox.cpp
+++ b/src/sst_mailbox.cpp
@@ -38,9 +38,11 @@
     bool peciWoken;
     CPUModel cpuModel;
     uint8_t mbBus;
+    WakePolicy wakePolicy;
 
-    PECIManager(uint8_t address, CPUModel model) :
-        peciAddress(address), peciWoken(false), cpuModel(model)
+    PECIManager(uint8_t address, CPUModel model, WakePolicy wakePolicy_) :
+        peciAddress(address), peciWoken(false), cpuModel(model),
+        wakePolicy(wakePolicy_)
     {
         mbBus = (model == icx) ? mbBusICX : mbBusOther;
     }
@@ -120,7 +122,7 @@
     void wrMailboxReg(uint16_t regAddress, uint32_t data)
     {
         uint8_t completionCode;
-        bool tryWaking = true;
+        bool tryWaking = (wakePolicy == wakeAllowed);
         while (true)
         {
             EPECIStatus libStatus = peci_WrEndPointPCIConfigLocal(
@@ -152,7 +154,7 @@
     {
         uint8_t completionCode;
         uint32_t outputData;
-        bool tryWaking = true;
+        bool tryWaking = (wakePolicy == wakeAllowed);
         while (true)
         {
             EPECIStatus libStatus = peci_RdEndPointConfigPciLocal(
@@ -397,9 +399,9 @@
     static constexpr int mhzPerRatio = 100;
 
   public:
-    SSTMailbox(uint8_t _address, CPUModel _model) :
+    SSTMailbox(uint8_t _address, CPUModel _model, WakePolicy wakePolicy) :
         address(_address), model(_model),
-        pm(static_cast<uint8_t>(address), model)
+        pm(static_cast<uint8_t>(address), model, wakePolicy)
     {}
     ~SSTMailbox() {}
 
@@ -568,8 +570,8 @@
     }
 };
 
-static std::unique_ptr<SSTInterface> createMailbox(uint8_t address,
-                                                   CPUModel model)
+static std::unique_ptr<SSTInterface>
+    createMailbox(uint8_t address, CPUModel model, WakePolicy wakePolicy)
 {
     DEBUG_PRINT << "createMailbox\n";
     switch (model)
@@ -578,7 +580,7 @@
         case icxd:
         case spr:
         case emr:
-            return std::make_unique<SSTMailbox>(address, model);
+            return std::make_unique<SSTMailbox>(address, model, wakePolicy);
         default:
             return nullptr;
     }