Updates DRAM minimum utilization to 25%

Change-Id: I7af6a56573e5190607977e5743055b4dc02f2511
CQ:SW396389
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/46696
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Reviewed-by: JACOB L. HARVEY <jlharvey@us.ibm.com>
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: HWSV CI <hwsv-ci+hostboot@us.ibm.com>
Tested-by: Hostboot CI <hostboot-ci+hostboot@us.ibm.com>
Reviewed-by: Louis Stermole <stermole@us.ibm.com>
Reviewed-by: ANDRE A. MARIN <aamarin@us.ibm.com>
Reviewed-by: Jennifer A. Stofer <stofer@us.ibm.com>
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/46706
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Reviewed-by: Daniel M. Crowell <dcrowell@us.ibm.com>

2 files changed, 18 insertions, 5 deletions

diff --git a/src/import/chips/p9/procedures/hwp/memory/lib/power_thermal/throttle.C b/src/import/chips/p9/procedures/hwp/memory/lib/power_thermal/throttle.C
index ee15073e5..ac0c1b739 100644
--- a/src/import/chips/p9/procedures/hwp/memory/lib/power_thermal/throttle.C
+++ b/src/import/chips/p9/procedures/hwp/memory/lib/power_thermal/throttle.C
@@ -49,6 +49,7 @@ namespace mss
 {
 namespace power_thermal
 {
+
 ///
 /// @brief Constructor
 /// @param[in] i_target MCS target to call power thermal stuff on
@@ -458,8 +459,13 @@ void throttle::calc_util_usage(const uint32_t i_slope,
     //Cast to uint32 for edge case where it has decimals
     o_util = (static_cast<uint32_t>(o_util) < iv_databus_port_max) ? static_cast<uint32_t>(o_util) : iv_databus_port_max;
 
-    //Can't have zero
-    o_util = (o_util == 0) ? MIN_UTIL : o_util;
+    // Check for the minimum threshnold and update if need be
+    if(o_util < MIN_UTIL)
+    {
+        FAPI_INF("Calculated utilization (%lu) is less than the minimum utilization: %lu. Setting to minimum value", o_util,
+                 MIN_UTIL);
+        o_util = MIN_UTIL;
+    }
 }
 
 ///
@@ -721,7 +727,7 @@ fapi_try_exit:
 ///
 fapi2::ReturnCode set_runtime_m_and_watt_limit( const std::vector< fapi2::Target<fapi2::TARGET_TYPE_MCS> >& i_targets )
 {
-    uint32_t l_m_clocks;
+    uint32_t l_m_clocks = 0;
     uint32_t l_vmem_power_limit_dimm = 0;
     uint8_t l_max_dimms = 0;
 
diff --git a/src/import/chips/p9/procedures/hwp/memory/lib/power_thermal/throttle.H b/src/import/chips/p9/procedures/hwp/memory/lib/power_thermal/throttle.H
index 70156eb04..637d1be79 100644
--- a/src/import/chips/p9/procedures/hwp/memory/lib/power_thermal/throttle.H
+++ b/src/import/chips/p9/procedures/hwp/memory/lib/power_thermal/throttle.H
@@ -57,7 +57,7 @@ enum throttle_const : size_t
     PERCENT_CONVERSION = 100,
 
     /// MIN_UTIL is  in c%
-    MIN_UTIL = 100,
+    MIN_UTIL = 2500,
 
     /// IDLE_UTIL is  in c%
     IDLE_UTIL = 0,
@@ -264,6 +264,7 @@ inline uint32_t throttled_cmds(const uint32_t i_databus_util, const uint32_t i_n
 
 ///
 /// @brief Calculate the port databus utilization based off of N throttles and M dram clocks
+/// @tparam T output type
 /// @param[in] i_n_throttles N (address operations) allowed within a window of M DRAM clocks
 /// @param[in] i_num_dram_clocks window of M DRAM clocks
 /// @param[out] o_calc_util
@@ -296,7 +297,13 @@ fapi2::ReturnCode calc_util_from_throttles(const uint16_t i_n_throttles,
                  l_multiplier,
                  i_num_dram_clocks);
 
-    o_calc_util = ( (o_calc_util == 0) ? MIN_UTIL : o_calc_util);
+    // Check for the minimum
+    if(o_calc_util < MIN_UTIL)
+    {
+        FAPI_INF("Calculated utilization (%lu) is less than the minimum utilization: %lu. Setting to minimum value",
+                 o_calc_util, MIN_UTIL);
+        o_calc_util = MIN_UTIL;
+    }
 
     FAPI_INF("In calc_util_from_throttles, calculated %d for output utilization", o_calc_util);
     return fapi2::FAPI2_RC_SUCCESS;