Adds NVDIMM RCW drive strength workaround

An NVDIMM supplier updated the drive strength
values for for the RCW's command/address/control
signals. The new drive strength causes the parts
to fail writes/reads. This commit restores the
old drive strength values.

Change-Id: If4d44f08cff2522de463b9a2ac57853950aa3356
CQ:SW478491
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/85229
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Reviewed-by: Louis Stermole <stermole@us.ibm.com>
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: Hostboot CI <hostboot-ci+hostboot@us.ibm.com>
Dev-Ready: STEPHEN GLANCY <sglancy@us.ibm.com>
Reviewed-by: JEREMY R NEATON <jrneaton@us.ibm.com>
Reviewed-by: TSUNG K YEUNG <tyeung@us.ibm.com>
Reviewed-by: Jennifer A Stofer <stofer@us.ibm.com>
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/85426
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Reviewed-by: Christian R Geddes <crgeddes@us.ibm.com>

3 files changed, 135 insertions, 0 deletions

diff --git a/src/import/chips/p9/procedures/hwp/memory/lib/dimm/eff_dimm.C b/src/import/chips/p9/procedures/hwp/memory/lib/dimm/eff_dimm.C
index 5074a5b4d..2c3a3a757 100644
--- a/src/import/chips/p9/procedures/hwp/memory/lib/dimm/eff_dimm.C
+++ b/src/import/chips/p9/procedures/hwp/memory/lib/dimm/eff_dimm.C
@@ -51,6 +51,7 @@
 #include <lib/phy/dp16.H>
 #include <lib/mss_attribute_accessors_manual.H>
 #include <generic/memory/lib/utils/freq/gen_mss_freq.H>
+#include <lib/workarounds/eff_config_workarounds.H>
 
 namespace mss
 {
@@ -1567,6 +1568,7 @@ fapi_try_exit:
 ///
 fapi2::ReturnCode eff_dimm::dimm_rc03()
 {
+    constexpr uint8_t NVDIMM_RCW_WORKAROUND_VALUE = 0x08;
     fapi2::buffer<uint8_t> l_buffer;
 
     uint8_t l_attrs_dimm_rc03[PORTS_PER_MCS][MAX_DIMM_PER_PORT] = {};
@@ -1589,6 +1591,10 @@ fapi2::ReturnCode eff_dimm::dimm_rc03()
         l_buffer.insertFromRight<CA_START, LEN>(l_ca_output_drive)
         .insertFromRight<CS_START, LEN>(l_cs_output_drive);
     }
+
+    // Update the value if the NVDIMM workaround is needed
+    FAPI_TRY(mss::workarounds::eff_config::nvdimm_rc_drive_strength(iv_dimm, NVDIMM_RCW_WORKAROUND_VALUE, l_buffer));
+
     // Retrieve MCS attribute data
     FAPI_TRY( eff_dimm_ddr4_rc03(iv_mcs, &l_attrs_dimm_rc03[0][0]) );
 
@@ -1608,6 +1614,7 @@ fapi_try_exit:
 ///
 fapi2::ReturnCode eff_dimm::dimm_rc04()
 {
+    constexpr uint8_t NVDIMM_RCW_WORKAROUND_VALUE = 0x0a;
     uint8_t l_attrs_dimm_rc04[PORTS_PER_MCS][MAX_DIMM_PER_PORT] = {};
     uint8_t l_odt_output_drive = 0;
     uint8_t l_cke_output_drive = 0;
@@ -1631,6 +1638,9 @@ fapi2::ReturnCode eff_dimm::dimm_rc04()
         .insertFromRight<ODT_START, LEN>(l_odt_output_drive);
     }
 
+    // Update the value if the NVDIMM workaround is needed
+    FAPI_TRY(mss::workarounds::eff_config::nvdimm_rc_drive_strength(iv_dimm, NVDIMM_RCW_WORKAROUND_VALUE, l_buffer));
+
     // Retrieve MCS attribute data
     FAPI_TRY( eff_dimm_ddr4_rc04(iv_mcs, &l_attrs_dimm_rc04[0][0]) );
 
@@ -1650,6 +1660,7 @@ fapi_try_exit:
 ///
 fapi2::ReturnCode eff_dimm::dimm_rc05()
 {
+    constexpr uint8_t NVDIMM_RCW_WORKAROUND_VALUE = 0x0a;
     uint8_t l_attrs_dimm_rc05[PORTS_PER_MCS][MAX_DIMM_PER_PORT] = {};
     uint8_t l_a_side_output_drive = 0;
     uint8_t l_b_side_output_drive = 0;
@@ -1673,6 +1684,9 @@ fapi2::ReturnCode eff_dimm::dimm_rc05()
         .insertFromRight<A_START, LEN>(l_a_side_output_drive);
     }
 
+    // Update the value if the NVDIMM workaround is needed
+    FAPI_TRY(mss::workarounds::eff_config::nvdimm_rc_drive_strength(iv_dimm, NVDIMM_RCW_WORKAROUND_VALUE, l_buffer));
+
     // Retrieve MCS attribute data
     FAPI_TRY( eff_dimm_ddr4_rc05(iv_mcs, &l_attrs_dimm_rc05[0][0]) );
 
diff --git a/src/import/chips/p9/procedures/hwp/memory/lib/workarounds/eff_config_workarounds.C b/src/import/chips/p9/procedures/hwp/memory/lib/workarounds/eff_config_workarounds.C
index 080023b8a..dae18167b 100644
--- a/src/import/chips/p9/procedures/hwp/memory/lib/workarounds/eff_config_workarounds.C
+++ b/src/import/chips/p9/procedures/hwp/memory/lib/workarounds/eff_config_workarounds.C
@@ -22,3 +22,73 @@
 /* permissions and limitations under the License.                         */
 /*                                                                        */
 /* IBM_PROLOG_END_TAG                                                     */
+
+
+#include <fapi2.H>
+#include <lib/mss_attribute_accessors.H>
+#include <lib/workarounds/eff_config_workarounds.H>
+
+namespace mss
+{
+
+namespace workarounds
+{
+
+namespace eff_config
+{
+
+///
+/// @brief Checks if the NVDIMM RC drive strength workaround is needed
+/// @param[in] i_target DIMM target on which to operate
+/// @param[out] o_is_needed true if the workaround is needed
+/// @return SUCCESS if the code executes successfully
+///
+fapi2::ReturnCode is_nvdimm_rc_drive_strength_needed(const fapi2::Target<fapi2::TARGET_TYPE_DIMM>& i_target,
+        bool& o_is_needed)
+{
+    o_is_needed = false;
+
+    uint8_t l_hybrid = 0;
+    uint8_t l_hybrid_type = 0;
+    uint32_t l_size = 0;
+
+    FAPI_TRY(mss::eff_hybrid(i_target, l_hybrid));
+    FAPI_TRY(mss::eff_hybrid_memory_type(i_target, l_hybrid_type));
+    FAPI_TRY(mss::eff_dimm_size(i_target, l_size));
+
+    if(l_hybrid == fapi2::ENUM_ATTR_EFF_HYBRID_IS_HYBRID &&
+       l_hybrid_type == fapi2::ENUM_ATTR_EFF_HYBRID_MEMORY_TYPE_NVDIMM &&
+       l_size == fapi2::ENUM_ATTR_EFF_DIMM_SIZE_32GB)
+    {
+        o_is_needed = true;
+    }
+
+fapi_try_exit:
+    return fapi2::current_err;
+}
+
+///
+/// @brief Updates the RC drive strength if the workaround is needed
+/// @param[in] i_target DIMM target on which to operate
+/// @param[in] i_override_value the value to override if the workaround needs to be applied
+/// @param[in,out] io_rc_value Register Control word value to update
+/// @return SUCCESS if the code executes successfully
+///
+fapi2::ReturnCode nvdimm_rc_drive_strength(const fapi2::Target<fapi2::TARGET_TYPE_DIMM>& i_target,
+        const uint8_t i_override_value,
+        fapi2::buffer<uint8_t>& io_rc_value)
+{
+    bool l_is_needed = false;
+    FAPI_TRY(is_nvdimm_rc_drive_strength_needed(i_target, l_is_needed));
+
+    // If the workaround is needed, overwrite it to be ALL_MODERATE values
+    // Otherwise keep it as it is
+    io_rc_value = l_is_needed ? fapi2::buffer<uint8_t>(i_override_value) : io_rc_value;
+
+fapi_try_exit:
+    return fapi2::current_err;
+}
+
+} // ns eff_config
+} // ns workarounds
+} // ns mss
diff --git a/src/import/chips/p9/procedures/hwp/memory/lib/workarounds/eff_config_workarounds.H b/src/import/chips/p9/procedures/hwp/memory/lib/workarounds/eff_config_workarounds.H
index ad8bee571..f41d9b89c 100644
--- a/src/import/chips/p9/procedures/hwp/memory/lib/workarounds/eff_config_workarounds.H
+++ b/src/import/chips/p9/procedures/hwp/memory/lib/workarounds/eff_config_workarounds.H
@@ -22,3 +22,54 @@
 /* permissions and limitations under the License.                         */
 /*                                                                        */
 /* IBM_PROLOG_END_TAG                                                     */
+
+///
+/// @file eff_config_workarounds.H
+/// @brief Workarounds for effective config
+/// Workarounds are very device specific, so there is no attempt to generalize
+/// this code in any way.
+///
+// *HWP HWP Owner: Stephen Glancy <sglancy@us.ibm.com>
+// *HWP HWP Backup: Andre Marin <aamarin@us.ibm.com>
+// *HWP Team: Memory
+// *HWP Level: 3
+// *HWP Consumed by: FSP:HB
+
+#ifndef _EFF_CONFIG_WORKAROUNDS_H_
+#define _EFF_CONFIG_WORKAROUNDS_H_
+
+#include <fapi2.H>
+
+namespace mss
+{
+
+namespace workarounds
+{
+
+namespace eff_config
+{
+
+///
+/// @brief Checks if the NVDIMM RC drive strength workaround is needed
+/// @param[in] i_target DIMM target on which to operate
+/// @param[out] o_is_needed true if the workaround is needed
+/// @return SUCCESS if the code executes successfully
+///
+fapi2::ReturnCode is_nvdimm_rc_drive_strength_needed(const fapi2::Target<fapi2::TARGET_TYPE_DIMM>& i_target,
+        bool& o_is_needed);
+
+///
+/// @brief Updates the RC drive strength if the workaround is needed
+/// @param[in] i_target DIMM target on which to operate
+/// @param[in] i_override_value the value to override if the workaround needs to be applied
+/// @param[in,out] io_rc_value Register Control word value to update
+/// @return SUCCESS if the code executes successfully
+///
+fapi2::ReturnCode nvdimm_rc_drive_strength(const fapi2::Target<fapi2::TARGET_TYPE_DIMM>& i_target,
+        const uint8_t i_override_value,
+        fapi2::buffer<uint8_t>& io_rc_value);
+
+} // ns eff_config
+} // ns workarounds
+} // ns mss
+#endif