diff --git a/cmake/AgentHwSwitchAsics.cmake b/cmake/AgentHwSwitchAsics.cmake
index 35313c3ce32db..30ac0cefb8532 100644
--- a/cmake/AgentHwSwitchAsics.cmake
+++ b/cmake/AgentHwSwitchAsics.cmake
@@ -29,6 +29,7 @@ add_library(switch_asics
   fboss/agent/hw/switch_asics/ChenabAsic.cpp
   fboss/agent/hw/switch_asics/BroadcomXgsAsic.cpp
   fboss/agent/hw/switch_asics/G202xAsic.cpp
+  fboss/agent/hw/switch_asics/Q4DAsic.cpp
 )
 
 target_link_libraries(switch_asics
diff --git a/fboss/agent/ApplyThriftConfig.cpp b/fboss/agent/ApplyThriftConfig.cpp
index ec0ed70bb3e31..e8449732e7288 100644
--- a/fboss/agent/ApplyThriftConfig.cpp
+++ b/fboss/agent/ApplyThriftConfig.cpp
@@ -1175,6 +1175,7 @@ void ThriftConfigApplier::processUpdatedDsfNodes() {
             asicCore = 1;
             break;
           case cfg::AsicType::ASIC_TYPE_JERICHO3:
+          case cfg::AsicType::ASIC_TYPE_Q4D:
             if (isDualStage3Q2QMode()) {
               asicCore = 447;
             } else {
diff --git a/fboss/agent/AsicUtils.cpp b/fboss/agent/AsicUtils.cpp
index 31261bdabcd90..c3d0dc9f8b900 100644
--- a/fboss/agent/AsicUtils.cpp
+++ b/fboss/agent/AsicUtils.cpp
@@ -10,6 +10,7 @@
 #include "fboss/agent/AsicUtils.h"
 #include "fboss/agent/hw/switch_asics/Jericho2Asic.h"
 #include "fboss/agent/hw/switch_asics/Jericho3Asic.h"
+#include "fboss/agent/hw/switch_asics/Q4DAsic.h"
 #include "fboss/agent/hw/switch_asics/Ramon3Asic.h"
 #include "fboss/agent/hw/switch_asics/RamonAsic.h"
 
@@ -39,6 +40,11 @@ const HwAsic& getHwAsicForAsicType(const cfg::AsicType& asicType) {
       static Jericho3Asic jericho3Asic{switchId, switchInfo};
       return jericho3Asic;
     }
+    case cfg::AsicType::ASIC_TYPE_Q4D: {
+      switchInfo.switchType() = cfg::SwitchType::VOQ;
+      static Q4DAsic q4dAsic{switchId, switchInfo};
+      return q4dAsic;
+    }
     case cfg::AsicType::ASIC_TYPE_RAMON: {
       switchInfo.switchType() = cfg::SwitchType::FABRIC;
       static RamonAsic ramonAsic{switchId, switchInfo};
@@ -82,6 +88,8 @@ uint32_t getFabricPortsPerVirtualDevice(const cfg::AsicType asicType) {
       return 192;
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
       return 160;
+    case cfg::AsicType::ASIC_TYPE_Q4D:
+      return 160;
     case cfg::AsicType::ASIC_TYPE_RAMON3:
       return 256;
     case cfg::AsicType::ASIC_TYPE_FAKE:
diff --git a/fboss/agent/PortUpdateHandler.cpp b/fboss/agent/PortUpdateHandler.cpp
index b4e48da1052fb..5f8238ca6698c 100644
--- a/fboss/agent/PortUpdateHandler.cpp
+++ b/fboss/agent/PortUpdateHandler.cpp
@@ -299,6 +299,7 @@ void PortUpdateHandler::computeFabricOverdrainPct(const StateDelta& delta) {
       case cfg::AsicType::ASIC_TYPE_JERICHO2:
         return 1.12;
       case cfg::AsicType::ASIC_TYPE_JERICHO3:
+      case cfg::AsicType::ASIC_TYPE_Q4D:
         return 1.06;
       case cfg::AsicType::ASIC_TYPE_MOCK:
       case cfg::AsicType::ASIC_TYPE_FAKE:
diff --git a/fboss/agent/hw/bcm/BcmFieldProcessorUtils.cpp b/fboss/agent/hw/bcm/BcmFieldProcessorUtils.cpp
index 832dd37702a53..c59e5d1bbb28d 100644
--- a/fboss/agent/hw/bcm/BcmFieldProcessorUtils.cpp
+++ b/fboss/agent/hw/bcm/BcmFieldProcessorUtils.cpp
@@ -543,6 +543,7 @@ bool needsExtraFPQsetQualifiers(cfg::AsicType asicType) {
     case cfg::AsicType::ASIC_TYPE_SANDIA_PHY:
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
     case cfg::AsicType::ASIC_TYPE_RAMON:
     case cfg::AsicType::ASIC_TYPE_RAMON3:
     case cfg::AsicType::ASIC_TYPE_G202X:
diff --git a/fboss/agent/hw/bcm/BcmSwitch.cpp b/fboss/agent/hw/bcm/BcmSwitch.cpp
index 8517f3ff18211..923f8bbb9609a 100644
--- a/fboss/agent/hw/bcm/BcmSwitch.cpp
+++ b/fboss/agent/hw/bcm/BcmSwitch.cpp
@@ -4222,6 +4222,7 @@ void BcmSwitch::disableHotSwap() const {
       case cfg::AsicType::ASIC_TYPE_SANDIA_PHY:
       case cfg::AsicType::ASIC_TYPE_JERICHO2:
       case cfg::AsicType::ASIC_TYPE_JERICHO3:
+      case cfg::AsicType::ASIC_TYPE_Q4D:
       case cfg::AsicType::ASIC_TYPE_RAMON:
       case cfg::AsicType::ASIC_TYPE_RAMON3:
       case cfg::AsicType::ASIC_TYPE_G202X:
diff --git a/fboss/agent/hw/bcm/tests/HwTestTamUtils.cpp b/fboss/agent/hw/bcm/tests/HwTestTamUtils.cpp
index 34ed3b111dcc9..ea8e416dec057 100644
--- a/fboss/agent/hw/bcm/tests/HwTestTamUtils.cpp
+++ b/fboss/agent/hw/bcm/tests/HwTestTamUtils.cpp
@@ -20,6 +20,7 @@ void triggerParityError(HwSwitchEnsemble* ensemble) {
     case cfg::AsicType::ASIC_TYPE_SANDIA_PHY:
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
     case cfg::AsicType::ASIC_TYPE_RAMON:
     case cfg::AsicType::ASIC_TYPE_RAMON3:
     case cfg::AsicType::ASIC_TYPE_EBRO:
diff --git a/fboss/agent/hw/bcm/tests/HwTestTamUtilsThriftHandler.cpp b/fboss/agent/hw/bcm/tests/HwTestTamUtilsThriftHandler.cpp
index 5d71acdd08818..83d4dc19182fe 100644
--- a/fboss/agent/hw/bcm/tests/HwTestTamUtilsThriftHandler.cpp
+++ b/fboss/agent/hw/bcm/tests/HwTestTamUtilsThriftHandler.cpp
@@ -19,6 +19,7 @@ void HwTestThriftHandler::triggerParityError() {
     case cfg::AsicType::ASIC_TYPE_SANDIA_PHY:
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
     case cfg::AsicType::ASIC_TYPE_RAMON:
     case cfg::AsicType::ASIC_TYPE_RAMON3:
     case cfg::AsicType::ASIC_TYPE_EBRO:
diff --git a/fboss/agent/hw/sai/hw_test/HwTestTamUtils.cpp b/fboss/agent/hw/sai/hw_test/HwTestTamUtils.cpp
index 3629cf64fd3db..c87f40203009d 100644
--- a/fboss/agent/hw/sai/hw_test/HwTestTamUtils.cpp
+++ b/fboss/agent/hw/sai/hw_test/HwTestTamUtils.cpp
@@ -141,6 +141,7 @@ void triggerParityError(HwSwitchEnsemble* ensemble) {
       triggerBcmJericho2ParityError(ensemble);
       break;
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
       triggerBcmJericho3ParityError(ensemble);
       break;
     case cfg::AsicType::ASIC_TYPE_CHENAB:
diff --git a/fboss/agent/hw/sai/hw_test/HwTestTamUtilsThriftHandler.cpp b/fboss/agent/hw/sai/hw_test/HwTestTamUtilsThriftHandler.cpp
index 357d8f02d4806..5cced993ac763 100644
--- a/fboss/agent/hw/sai/hw_test/HwTestTamUtilsThriftHandler.cpp
+++ b/fboss/agent/hw/sai/hw_test/HwTestTamUtilsThriftHandler.cpp
@@ -236,6 +236,7 @@ void HwTestThriftHandler::triggerParityError() {
       triggerBcmJericho2ParityError(hwSwitch_);
       break;
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
       triggerBcmJericho3ParityError(hwSwitch_);
       break;
     case cfg::AsicType::ASIC_TYPE_CHENAB:
diff --git a/fboss/agent/hw/sai/switch/SaiAclTableManager.cpp b/fboss/agent/hw/sai/switch/SaiAclTableManager.cpp
index 30ceb503f6f29..a1e703fa28e41 100644
--- a/fboss/agent/hw/sai/switch/SaiAclTableManager.cpp
+++ b/fboss/agent/hw/sai/switch/SaiAclTableManager.cpp
@@ -1682,8 +1682,9 @@ std::set<cfg::AclTableQualifier> SaiAclTableManager::getSupportedQualifierSet(
       platform_->getAsic()->getAsicType() == cfg::AsicType::ASIC_TYPE_TRIDENT2;
   bool isJericho2 =
       platform_->getAsic()->getAsicType() == cfg::AsicType::ASIC_TYPE_JERICHO2;
-  bool isJericho3 =
-      platform_->getAsic()->getAsicType() == cfg::AsicType::ASIC_TYPE_JERICHO3;
+  bool isJericho3 = platform_->getAsic()->getAsicType() ==
+          cfg::AsicType::ASIC_TYPE_JERICHO3 ||
+      platform_->getAsic()->getAsicType() == cfg::AsicType::ASIC_TYPE_Q4D;
   bool isTomahawk5 =
       platform_->getAsic()->getAsicType() == cfg::AsicType::ASIC_TYPE_TOMAHAWK5;
   bool isChenab =
diff --git a/fboss/agent/hw/sai/switch/SaiBufferManager.cpp b/fboss/agent/hw/sai/switch/SaiBufferManager.cpp
index 31742f7d3af7a..a63a6be974742 100644
--- a/fboss/agent/hw/sai/switch/SaiBufferManager.cpp
+++ b/fboss/agent/hw/sai/switch/SaiBufferManager.cpp
@@ -109,6 +109,7 @@ void assertMaxBufferPoolSize(const SaiPlatform* platform) {
       break;
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
     case cfg::AsicType::ASIC_TYPE_TRIDENT2:
       CHECK_EQ(maxEgressPoolSize, availableBuffer);
       break;
@@ -201,6 +202,7 @@ uint64_t SaiBufferManager::getMaxEgressPoolBytes(const SaiPlatform* platform) {
     }
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
       /*
        * XXX: TODO: Need to check if there is a way to compute the
        * buffers available for use in Jericho2 without using the
diff --git a/fboss/agent/hw/sai/switch/SaiPortManager.cpp b/fboss/agent/hw/sai/switch/SaiPortManager.cpp
index 30897e2a51805..f261e01f1b3ad 100644
--- a/fboss/agent/hw/sai/switch/SaiPortManager.cpp
+++ b/fboss/agent/hw/sai/switch/SaiPortManager.cpp
@@ -611,6 +611,7 @@ int getWorstCaseAssumedOpticsDelayNS(
     case cfg::AsicType::ASIC_TYPE_G202X:
       break;
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
       if (portType == cfg::PortType::FABRIC_PORT) {
         return 110;
       } else {
diff --git a/fboss/agent/hw/sai/switch/SaiVirtualRouterManager.cpp b/fboss/agent/hw/sai/switch/SaiVirtualRouterManager.cpp
index 93d52d0ad656c..3d7282a20e254 100644
--- a/fboss/agent/hw/sai/switch/SaiVirtualRouterManager.cpp
+++ b/fboss/agent/hw/sai/switch/SaiVirtualRouterManager.cpp
@@ -110,6 +110,7 @@ SaiVirtualRouterManager::createMplsRouterInterface(VirtualRouterSaiId vrId) {
     case cfg::AsicType::ASIC_TYPE_SANDIA_PHY:
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
     case cfg::AsicType::ASIC_TYPE_RAMON:
     case cfg::AsicType::ASIC_TYPE_RAMON3:
     case cfg::AsicType::ASIC_TYPE_CHENAB:
diff --git a/fboss/agent/hw/switch_asics/HwAsic.cpp b/fboss/agent/hw/switch_asics/HwAsic.cpp
index 676391b85d34d..087af1078dcba 100644
--- a/fboss/agent/hw/switch_asics/HwAsic.cpp
+++ b/fboss/agent/hw/switch_asics/HwAsic.cpp
@@ -19,6 +19,7 @@
 #include "fboss/agent/hw/switch_asics/Jericho2Asic.h"
 #include "fboss/agent/hw/switch_asics/Jericho3Asic.h"
 #include "fboss/agent/hw/switch_asics/MockAsic.h"
+#include "fboss/agent/hw/switch_asics/Q4DAsic.h"
 #include "fboss/agent/hw/switch_asics/Ramon3Asic.h"
 #include "fboss/agent/hw/switch_asics/RamonAsic.h"
 #include "fboss/agent/hw/switch_asics/Tomahawk3Asic.h"
@@ -120,6 +121,8 @@ std::unique_ptr<HwAsic> HwAsic::makeAsic(
       return std::make_unique<Jericho2Asic>(switchId, switchInfo, sdkVersion);
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
       return std::make_unique<Jericho3Asic>(switchId, switchInfo, sdkVersion);
+    case cfg::AsicType::ASIC_TYPE_Q4D:
+      return std::make_unique<Q4DAsic>(switchId, switchInfo, sdkVersion);
     case cfg::AsicType::ASIC_TYPE_RAMON:
       return std::make_unique<RamonAsic>(switchId, switchInfo, sdkVersion);
     case cfg::AsicType::ASIC_TYPE_RAMON3:
diff --git a/fboss/agent/hw/switch_asics/Q4DAsic.cpp b/fboss/agent/hw/switch_asics/Q4DAsic.cpp
new file mode 100644
index 0000000000000..62f039141f105
--- /dev/null
+++ b/fboss/agent/hw/switch_asics/Q4DAsic.cpp
@@ -0,0 +1,255 @@
+// Copyright 2004-present Facebook. All Rights Reserved.
+
+#include "fboss/agent/hw/switch_asics/Q4DAsic.h"
+#include <thrift/lib/cpp/util/EnumUtils.h>
+#include "fboss/agent/AgentFeatures.h"
+
+namespace facebook::fboss {
+
+bool Q4DAsic::isSupported(Feature feature) const {
+  switch (feature) {
+    case HwAsic::Feature::OBJECT_KEY_CACHE:
+    case HwAsic::Feature::PKTIO:
+    case HwAsic::Feature::HOSTTABLE:
+    case HwAsic::Feature::OBM_COUNTERS:
+    case HwAsic::Feature::MIRROR_PACKET_TRUNCATION:
+    case HwAsic::Feature::SFLOW_SAMPLING:
+    case HwAsic::Feature::TELEMETRY_AND_MONITORING:
+    case HwAsic::Feature::WIDE_ECMP:
+    case HwAsic::Feature::ALPM_ROUTE_PROJECTION:
+    case HwAsic::Feature::MAC_AGING:
+    case HwAsic::Feature::SAI_PORT_SPEED_CHANGE: // CS00011784917
+    case HwAsic::Feature::EGRESS_MIRRORING:
+    case HwAsic::Feature::EGRESS_SFLOW:
+    case HwAsic::Feature::DEFAULT_VLAN:
+    case HwAsic::Feature::CPU_PORT:
+    case HwAsic::Feature::CPU_QUEUES:
+    case HwAsic::Feature::VRF:
+    case HwAsic::Feature::SAI_HASH_FIELDS_CLEAR_BEFORE_SET:
+    case HwAsic::Feature::SAI_WEIGHTED_NEXTHOPGROUP_MEMBER:
+    case HwAsic::Feature::PORT_TX_DISABLE:
+    case HwAsic::Feature::SAI_PORT_ERR_STATUS:
+    case HwAsic::Feature::ROUTE_PROGRAMMING:
+    case HwAsic::Feature::FABRIC_PORTS:
+    case HwAsic::Feature::LINK_TRAINING:
+    case HwAsic::Feature::FEC:
+    case HwAsic::Feature::SAI_TTL0_PACKET_FORWARD_ENABLE:
+    case HwAsic::Feature::PMD_RX_LOCK_STATUS:
+    case HwAsic::Feature::PMD_RX_SIGNAL_DETECT:
+    case HwAsic::Feature::MEDIA_TYPE:
+    case HwAsic::Feature::PORT_FABRIC_ISOLATE:
+    case HwAsic::Feature::CPU_TX_VIA_RECYCLE_PORT:
+    case HwAsic::Feature::SWITCH_DROP_STATS:
+    case HwAsic::Feature::PACKET_INTEGRITY_DROP_STATS:
+    case HwAsic::Feature::SAI_CONFIGURE_SIX_TAP:
+    case HwAsic::Feature::DRAM_ENQUEUE_DEQUEUE_STATS:
+    case HwAsic::Feature::RESOURCE_USAGE_STATS:
+    case HwAsic::Feature::SAI_FEC_COUNTERS:
+    case HwAsic::Feature::SAI_FEC_CORRECTED_BITS:
+    case HwAsic::Feature::BLACKHOLE_ROUTE_DROP_COUNTER:
+    case HwAsic::Feature::ECN:
+    case HwAsic::Feature::SAI_ECN_WRED:
+    case HwAsic::Feature::QUEUE_ECN_COUNTER:
+    case HwAsic::Feature::MANAGEMENT_PORT:
+    case HwAsic::Feature::ANY_ACL_DROP_COUNTER:
+    case HwAsic::Feature::EGRESS_FORWARDING_DROP_COUNTER:
+    case HwAsic::Feature::ACL_COUNTER_LABEL:
+    case HwAsic::Feature::SWITCH_ATTR_INGRESS_ACL:
+    case HwAsic::Feature::ACL_TABLE_GROUP:
+    case HwAsic::Feature::ERSPANv4:
+    case HwAsic::Feature::ERSPANv6:
+    case HwAsic::Feature::RCI_WATERMARK_COUNTER:
+    case HwAsic::Feature::SAI_ACL_ENTRY_SRC_PORT_QUALIFIER:
+    case HwAsic::Feature::SAI_PRBS:
+    case HwAsic::Feature::PORT_SERDES_ZERO_PREEMPHASIS:
+    case HwAsic::Feature::LINK_ACTIVE_INACTIVE_NOTIFY:
+    case HwAsic::Feature::WARMBOOT:
+    case HwAsic::Feature::PQP_ERROR_EGRESS_DROP_COUNTER:
+    case HwAsic::Feature::FABRIC_LINK_DOWN_CELL_DROP_COUNTER:
+    case HwAsic::Feature::CRC_ERROR_DETECT:
+    case HwAsic::Feature::ACL_METADATA_QUALIFER:
+    case HwAsic::Feature::EVENTOR_PORT_FOR_SFLOW:
+    case HwAsic::Feature::SFLOWv6:
+    case HwAsic::Feature::ZERO_SDK_WRITE_WARMBOOT:
+    case HwAsic::Feature::SWITCH_REACHABILITY_CHANGE_NOTIFY:
+    case HwAsic::Feature::CABLE_PROPOGATION_DELAY:
+    case HwAsic::Feature::DRAM_BLOCK_TIME:
+    case HwAsic::Feature::VOQ_LATENCY_WATERMARK_BIN:
+    case HwAsic::Feature::ACL_ENTRY_ETHER_TYPE:
+    case HwAsic::Feature::ACL_BYTE_COUNTER:
+    case HwAsic::Feature::EGRESS_CORE_BUFFER_WATERMARK:
+    case HwAsic::Feature::DELETED_CREDITS_STAT:
+    case HwAsic::Feature::INGRESS_PRIORITY_GROUP_DROPPED_PACKETS:
+    case HwAsic::Feature::ROUTE_METADATA:
+    case HwAsic::Feature::NO_RX_REASON_TRAP:
+    case HwAsic::Feature::EGRESS_GVOQ_WATERMARK_BYTES:
+    case HwAsic::Feature::INGRESS_PRIORITY_GROUP_SHARED_WATERMARK:
+    case HwAsic::Feature::PORT_MTU_ERROR_TRAP:
+    case HwAsic::Feature::FAST_LLFC_COUNTER:
+    case HwAsic::Feature::INGRESS_SRAM_MIN_BUFFER_WATERMARK:
+    case HwAsic::Feature::FDR_FIFO_WATERMARK:
+    case HwAsic::Feature::EGRESS_CELL_ERROR_STATS:
+    case HwAsic::Feature::ECMP_MEMBER_WIDTH_INTROSPECTION:
+    case HwAsic::Feature::CPU_QUEUE_WATERMARK_STATS:
+    case HwAsic::Feature::SAMPLE_RATE_CONFIG_PER_MIRROR:
+    case HwAsic::Feature::SFLOW_SAMPLES_PACKING:
+    case HwAsic::Feature::VENDOR_SWITCH_NOTIFICATION:
+    case HwAsic::Feature::SDK_REGISTER_DUMP:
+    case HwAsic::Feature::FEC_ERROR_DETECT_ENABLE:
+    case HwAsic::Feature::BUFFER_POOL_HEADROOM_WATERMARK:
+    case HwAsic::Feature::SAI_SET_TC_WITH_USER_DEFINED_TRAP_CPU_ACTION:
+    case HwAsic::Feature::DRAM_DATAPATH_PACKET_ERROR_STATS:
+    case HwAsic::Feature::EGRESS_POOL_AVAILABLE_SIZE_ATTRIBUTE_SUPPORTED:
+    case HwAsic::Feature::VENDOR_SWITCH_CONGESTION_MANAGEMENT_ERRORS:
+    case HwAsic::Feature::ASIC_RESET_NOTIFICATIONS:
+    case HwAsic::Feature::RX_SERDES_PARAMETERS:
+    case HwAsic::Feature::BULK_CREATE_ECMP_MEMBER:
+    case HwAsic::Feature::TECH_SUPPORT:
+    case HwAsic::Feature::DRAM_QUARANTINED_BUFFER_STATS:
+    case HwAsic::Feature::FABRIC_LINK_MONITORING:
+    case HwAsic::Feature::TEMPERATURE_MONITORING:
+      return true;
+    // Features not expected to work on SIM
+    case HwAsic::Feature::SHARED_INGRESS_EGRESS_BUFFER_POOL:
+    case HwAsic::Feature::BUFFER_POOL:
+    case HwAsic::Feature::PFC:
+    case HwAsic::Feature::PFC_XON_TO_XOFF_COUNTER:
+    case HwAsic::Feature::SAI_PORT_SERDES_FIELDS_RESET:
+    case HwAsic::Feature::VOQ:
+    case HwAsic::Feature::FABRIC_TX_QUEUES:
+    case HwAsic::Feature::VOQ_DELETE_COUNTER:
+    case HwAsic::Feature::L3_QOS:
+    case HwAsic::Feature::TC_TO_QUEUE_QOS_MAP_ON_SYSTEM_PORT:
+    case HwAsic::Feature::CREDIT_WATCHDOG:
+    case HwAsic::Feature::SAI_PORT_SERDES_PROGRAMMING:
+      return getAsicMode() != AsicMode::ASIC_MODE_SIM;
+    // SIM specific features.
+    case HwAsic::Feature::SAI_PORT_ETHER_STATS:
+    case HwAsic::Feature::SLOW_STAT_UPDATE:
+      // supported only on the SIM
+      return getAsicMode() == AsicMode::ASIC_MODE_SIM;
+    case HwAsic::Feature::RESERVED_ENCAP_INDEX_RANGE:
+    case HwAsic::Feature::UDF_HASH_FIELD_QUERY:
+    case HwAsic::Feature::IN_PAUSE_INCREMENTS_DISCARDS:
+    case HwAsic::Feature::SAI_LAG_HASH:
+    case HwAsic::Feature::QOS_MAP_GLOBAL:
+    case HwAsic::Feature::QCM:
+    case HwAsic::Feature::SMAC_EQUALS_DMAC_CHECK_ENABLED:
+    case HwAsic::Feature::PORT_TTL_DECREMENT_DISABLE:
+    case HwAsic::Feature::PORT_INTERFACE_TYPE:
+    case HwAsic::Feature::WEIGHTED_NEXTHOPGROUP_MEMBER:
+    case HwAsic::Feature::HSDK:
+    case HwAsic::Feature::L3_EGRESS_MODE_AUTO_ENABLED:
+    case HwAsic::Feature::INGRESS_FIELD_PROCESSOR_FLEX_COUNTER:
+    case HwAsic::Feature::PENDING_L2_ENTRY:
+    case HwAsic::Feature::EGRESS_QUEUE_FLEX_COUNTER:
+    case HwAsic::Feature::INGRESS_L3_INTERFACE:
+    case HwAsic::Feature::NON_UNICAST_HASH:
+    case HwAsic::Feature::DETAILED_L2_UPDATE:
+    case HwAsic::Feature::COUNTER_REFRESH_INTERVAL:
+    case HwAsic::Feature::SFLOW_SHIM_VERSION_FIELD:
+    case HwAsic::Feature::REMOVE_PORTS_FOR_COLDBOOT: // CS00012066057
+    case HwAsic::Feature::MACSEC:
+    case HwAsic::Feature::SAI_MPLS_QOS:
+    case HwAsic::Feature::EMPTY_ACL_MATCHER:
+    case HwAsic::Feature::ROUTE_FLEX_COUNTERS:
+    case HwAsic::Feature::FEC_DIAG_COUNTERS:
+    case HwAsic::Feature::SAI_ACL_TABLE_UPDATE:
+    case HwAsic::Feature::SAI_MPLS_TTL_1_TRAP:
+    case HwAsic::Feature::SAI_MPLS_LABEL_LOOKUP_FAIL_COUNTER:
+    case HwAsic::Feature::EXACT_MATCH:
+    case HwAsic::Feature::RX_FREQUENCY_PPM:
+    case HwAsic::Feature::SAI_FIRMWARE_PATH:
+    // On Q4D ASIC we don't create any vlans but rather
+    // associate RIFs directly with ports. Hence no bridge port
+    // is created (or supported for now).
+    case HwAsic::Feature::BRIDGE_PORT_8021Q:
+    case HwAsic::Feature::EXTENDED_FEC:
+    case HwAsic::Feature::SAI_RX_REASON_COUNTER:
+    case HwAsic::Feature::SAI_MPLS_INSEGMENT:
+    case HwAsic::Feature::XPHY_PORT_STATE_TOGGLE:
+    case HwAsic::Feature::SAI_PORT_GET_PMD_LANES:
+    case HwAsic::Feature::SAI_PORT_VCO_CHANGE:
+    case HwAsic::Feature::ARS:
+    case HwAsic::Feature::P4_WARMBOOT:
+    case HwAsic::Feature::FEC_AM_LOCK_STATUS:
+    case HwAsic::Feature::PCS_RX_LINK_STATUS:
+    case HwAsic::Feature::SAI_CONFIGURE_SEVEN_TAP:
+    case HwAsic::Feature::SAI_SAMPLEPACKET_TRAP:
+    case HwAsic::Feature::SAI_UDF_HASH:
+    case HwAsic::Feature::PTP_TC:
+    case HwAsic::Feature::PTP_TC_PCS:
+    case HwAsic::Feature::INGRESS_PRIORITY_GROUP_HEADROOM_WATERMARK:
+    case HwAsic::Feature::RX_LANE_SQUELCH_ENABLE:
+    case HwAsic::Feature::SEPARATE_BYTE_AND_PACKET_ACL_COUNTER:
+    case HwAsic::Feature::ARS_PORT_ATTRIBUTES:
+    case HwAsic::Feature::ARS_ALTERNATE_MEMBERS:
+    case HwAsic::Feature::SAI_EAPOL_TRAP:
+    case HwAsic::Feature::SAI_USER_DEFINED_TRAP:
+    case HwAsic::Feature::PORT_EYE_VALUES:
+    case HwAsic::Feature::ECMP_DLB_OFFSET:
+    case HwAsic::Feature::SPAN:
+    case HwAsic::Feature::SFLOWv4:
+    case HwAsic::Feature::MPLS:
+    case HwAsic::Feature::MPLS_ECMP:
+    case HwAsic::Feature::RX_SNR:
+    case HwAsic::Feature::FEC_CORRECTED_BITS:
+    case HwAsic::Feature::ROUTE_COUNTERS:
+    // J3-AI natively supports hashing. So hash configuration is not supported.
+    case HwAsic::Feature::HASH_FIELDS_CUSTOMIZATION:
+    case HwAsic::Feature::ECMP_HASH_V4:
+    case HwAsic::Feature::ECMP_HASH_V6:
+    case HwAsic::Feature::TRAFFIC_HASHING:
+    case HwAsic::Feature::PORT_WRED_COUNTER:
+    case HwAsic::Feature::DTL_WATERMARK_COUNTER:
+    case HwAsic::Feature::MULTIPLE_ACL_TABLES:
+    case HwAsic::Feature::SAI_ECMP_HASH_ALGORITHM:
+    case HwAsic::Feature::SCHEDULER_PPS:
+    case HwAsic::Feature::DATA_CELL_FILTER:
+    case HwAsic::Feature::MULTIPLE_EGRESS_BUFFER_POOL:
+    case HwAsic::Feature::ENABLE_DELAY_DROP_CONGESTION_THRESHOLD:
+    case HwAsic::Feature::L3_MTU_ERROR_TRAP:
+    case HwAsic::Feature::L3_INTF_MTU:
+    case HwAsic::Feature::DEDICATED_CPU_BUFFER_POOL:
+    case HwAsic::Feature::INGRESS_POST_LOOKUP_ACL_TABLE:
+    case HwAsic::Feature::SAI_HOST_MISS_TRAP:
+    case HwAsic::Feature::CPU_TX_PACKET_REQUIRES_VLAN_TAG:
+    case HwAsic::Feature::SWITCH_ASIC_SDK_HEALTH_NOTIFY:
+    case HwAsic::Feature::PFC_WATCHDOG_TIMER_GRANULARITY:
+    case HwAsic::Feature::SAI_PORT_IN_CONGESTION_DISCARDS:
+    case HwAsic::Feature::ROUTER_INTERFACE_STATISTICS:
+    case HwAsic::Feature::CPU_PORT_EGRESS_BUFFER_POOL:
+    case HwAsic::Feature::ACL_SET_ECMP_HASH_ALGORITHM:
+    case HwAsic::Feature::SET_NEXT_HOP_GROUP_HASH_ALGORITHM:
+    case HwAsic::Feature::MANAGEMENT_PORT_MULTICAST_QUEUE_ALPHA:
+    case HwAsic::Feature::SAI_PORT_PG_DROP_STATUS:
+    case HwAsic::Feature::FABRIC_INTER_CELL_JITTER_WATERMARK:
+    case HwAsic::Feature::MAC_TRANSMIT_DATA_QUEUE_WATERMARK:
+    /*
+     * Q4D does not support NEXTHOP_TTL_DECREMENT_DISABLE. Similar effect is
+     * achieved by configuring to forward TTL0 packets by enabling
+     * SAI_TTL0_PACKET_FORWARD_ENABLE.
+     */
+    case HwAsic::Feature::NEXTHOP_TTL_DECREMENT_DISABLE:
+    case HwAsic::Feature::RESERVED_BYTES_FOR_BUFFER_POOL:
+    case HwAsic::Feature::INGRESS_BUFFER_POOL_SIZE_EXCLUDES_HEADROOM:
+    case HwAsic::Feature::IN_DISCARDS_EXCLUDES_PFC:
+    case HwAsic::Feature::PORT_LEVEL_BUFFER_CONFIGURATION_SUPPORT:
+    case HwAsic::Feature::SAI_SERDES_RX_REACH:
+    case HwAsic::Feature::SAI_SERDES_PRECODING:
+    case HwAsic::Feature::ARS_FUTURE_PORT_LOAD:
+    case HwAsic::Feature::ECN_PROBABILISTIC_MARKING:
+    case HwAsic::Feature::SWITCH_DROP_DEBUG_COUNTER:
+    // Disabling ANY_TRAP_DROP_COUNTER for the time being.
+    // This will result in an early return in
+    // SaiDebugCounterManager::setupTrapDropCounter(), which is currently
+    // failing with SAI 14.x
+    case HwAsic::Feature::ANY_TRAP_DROP_COUNTER:
+    case HwAsic::Feature::SAI_FEC_CODEWORDS_STATS:
+    case HwAsic::Feature::LINK_INACTIVE_BASED_ISOLATE:
+      return false;
+  }
+  return false;
+}
+
+} // namespace facebook::fboss
diff --git a/fboss/agent/hw/switch_asics/Q4DAsic.h b/fboss/agent/hw/switch_asics/Q4DAsic.h
new file mode 100644
index 0000000000000..f36e6b47f0973
--- /dev/null
+++ b/fboss/agent/hw/switch_asics/Q4DAsic.h
@@ -0,0 +1,33 @@
+// Copyright 2004-present Facebook. All Rights Reserved.
+
+#pragma once
+
+#include <optional>
+#include "fboss/agent/hw/switch_asics/Jericho3Asic.h"
+
+namespace facebook::fboss {
+
+class Q4DAsic : public Jericho3Asic {
+ public:
+  Q4DAsic(
+      std::optional<int64_t> switchId,
+      cfg::SwitchInfo switchInfo,
+      std::optional<cfg::SdkVersion> sdkVersion = std::nullopt)
+      : Jericho3Asic(switchId, switchInfo, sdkVersion) {}
+
+  bool isSupported(Feature) const override;
+
+  cfg::AsicType getAsicType() const override {
+    return cfg::AsicType::ASIC_TYPE_Q4D;
+  }
+
+  cfg::PortSpeed getMaxPortSpeed() const override {
+    return cfg::PortSpeed::EIGHTHUNDREDG;
+  }
+
+  uint32_t getNumCores() const override {
+    return 8;
+  }
+};
+
+} // namespace facebook::fboss
diff --git a/fboss/agent/hw/test/HwHashPolarizationTestUtils.cpp b/fboss/agent/hw/test/HwHashPolarizationTestUtils.cpp
index bc48f906f5c64..e2e4aa38b0d57 100644
--- a/fboss/agent/hw/test/HwHashPolarizationTestUtils.cpp
+++ b/fboss/agent/hw/test/HwHashPolarizationTestUtils.cpp
@@ -57,6 +57,7 @@ std::unique_ptr<std::vector<utility::EthFrame>> getFullHashedPackets(
       case cfg::AsicType::ASIC_TYPE_AGERA3:
       case cfg::AsicType::ASIC_TYPE_JERICHO2:
       case cfg::AsicType::ASIC_TYPE_JERICHO3:
+      case cfg::AsicType::ASIC_TYPE_Q4D:
       case cfg::AsicType::ASIC_TYPE_RAMON:
       case cfg::AsicType::ASIC_TYPE_RAMON3:
       case cfg::AsicType::ASIC_TYPE_G202X:
@@ -88,6 +89,7 @@ std::unique_ptr<std::vector<utility::EthFrame>> getFullHashedPackets(
       case cfg::AsicType::ASIC_TYPE_SANDIA_PHY:
       case cfg::AsicType::ASIC_TYPE_JERICHO2:
       case cfg::AsicType::ASIC_TYPE_JERICHO3:
+      case cfg::AsicType::ASIC_TYPE_Q4D:
       case cfg::AsicType::ASIC_TYPE_RAMON:
       case cfg::AsicType::ASIC_TYPE_RAMON3:
       case cfg::AsicType::ASIC_TYPE_G202X:
diff --git a/fboss/agent/hw/test/dataplane_tests/HwProdInvariantHelper.cpp b/fboss/agent/hw/test/dataplane_tests/HwProdInvariantHelper.cpp
index efc3ee16d28c7..10fc998676d73 100644
--- a/fboss/agent/hw/test/dataplane_tests/HwProdInvariantHelper.cpp
+++ b/fboss/agent/hw/test/dataplane_tests/HwProdInvariantHelper.cpp
@@ -174,6 +174,7 @@ void HwProdInvariantHelper::verifySafeDiagCmds() {
     case cfg::AsicType::ASIC_TYPE_SANDIA_PHY:
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
     case cfg::AsicType::ASIC_TYPE_RAMON:
     case cfg::AsicType::ASIC_TYPE_RAMON3:
     case cfg::AsicType::ASIC_TYPE_TOMAHAWK5:
diff --git a/fboss/agent/platforms/sai/SaiPlatform.cpp b/fboss/agent/platforms/sai/SaiPlatform.cpp
index b0e0ba95d1352..997b46c276b22 100644
--- a/fboss/agent/platforms/sai/SaiPlatform.cpp
+++ b/fboss/agent/platforms/sai/SaiPlatform.cpp
@@ -17,6 +17,7 @@
 #include "fboss/agent/hw/sai/switch/SaiSwitch.h"
 #include "fboss/agent/hw/switch_asics/HwAsic.h"
 #include "fboss/agent/hw/switch_asics/Jericho3Asic.h"
+#include "fboss/agent/hw/switch_asics/Q4DAsic.h"
 #include "fboss/agent/platforms/sai/SaiBcmDarwinPlatformPort.h"
 #include "fboss/agent/platforms/sai/SaiBcmElbertPlatformPort.h"
 #include "fboss/agent/platforms/sai/SaiBcmFujiPlatformPort.h"
@@ -556,6 +557,7 @@ SaiSwitchTraits::CreateAttributes SaiPlatform::getSwitchAttributes(
       swInfo.switchType() = cfg::SwitchType::VOQ;
       swInfo.switchMac() = localMac.toString();
       const Jericho3Asic j3(0, swInfo);
+      const Q4DAsic q4d(0, swInfo);
       for (const auto& [id, dsfNode] : *agentCfg->thrift.sw()->dsfNodes()) {
         if (dsfNode.type() != cfg::DsfNodeType::INTERFACE_NODE) {
           continue;
@@ -568,6 +570,11 @@ SaiSwitchTraits::CreateAttributes SaiPlatform::getSwitchAttributes(
             maxSystemCoreCount =
                 std::max(maxSystemCoreCount, uint32_t(id + j3.getNumCores()));
             break;
+          case cfg::AsicType::ASIC_TYPE_Q4D:
+            maxCoreCount = std::max(q4d.getNumCores(), maxCoreCount);
+            maxSystemCoreCount =
+                std::max(maxSystemCoreCount, uint32_t(id + q4d.getNumCores()));
+            break;
           default:
             throw FbossError("Unexpected asic type: ", *dsfNode.asicType());
         }
@@ -911,6 +918,13 @@ SaiSwitchTraits::CreateAttributes SaiPlatform::getSwitchAttributes(
   }
 #endif
 
+  // Q4D bringup - Override max sysports and voqs for Q4D standalone box.
+  if (getAsic()->getAsicType() == cfg::AsicType::ASIC_TYPE_Q4D) {
+    maxSystemPorts = 1024;
+    maxVoqs = 8 * 1024;
+    maxSystemPortId = 1024 - 1;
+  }
+
   return {
       initSwitch,
       hwInfo, // hardware info
diff --git a/fboss/agent/switch_config.thrift b/fboss/agent/switch_config.thrift
index 0c8916c688ada..231006686b970 100644
--- a/fboss/agent/switch_config.thrift
+++ b/fboss/agent/switch_config.thrift
@@ -1543,6 +1543,7 @@ enum AsicType {
   ASIC_TYPE_G202X = 20,
   ASIC_TYPE_FAKE_NO_WARMBOOT = 21,
   ASIC_TYPE_TOMAHAWKULTRA1 = 22,
+  ASIC_TYPE_Q4D = 23,
 }
 /**
  * The configuration for an interface
diff --git a/fboss/agent/test/agent_hw_tests/AgentDiagShellStressTests.cpp b/fboss/agent/test/agent_hw_tests/AgentDiagShellStressTests.cpp
index 827e2b709e2b7..40b7953f62bd6 100644
--- a/fboss/agent/test/agent_hw_tests/AgentDiagShellStressTests.cpp
+++ b/fboss/agent/test/agent_hw_tests/AgentDiagShellStressTests.cpp
@@ -33,6 +33,7 @@ class AgentDiagShellStressTest : public AgentHwTest {
           // No diag shell to test for these ASICs
           break;
         case cfg::AsicType::ASIC_TYPE_JERICHO3:
+        case cfg::AsicType::ASIC_TYPE_Q4D:
           runBcmDnxCmds(switchId);
           break;
         case cfg::AsicType::ASIC_TYPE_EBRO:
diff --git a/fboss/agent/test/prod_agent_tests/ProdInvariantTests.cpp b/fboss/agent/test/prod_agent_tests/ProdInvariantTests.cpp
index 3a83d95bfbb9f..8cc97365ccb03 100644
--- a/fboss/agent/test/prod_agent_tests/ProdInvariantTests.cpp
+++ b/fboss/agent/test/prod_agent_tests/ProdInvariantTests.cpp
@@ -373,6 +373,7 @@ void ProdInvariantTest::verifySafeDiagCommands() {
     case cfg::AsicType::ASIC_TYPE_AGERA3:
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
     case cfg::AsicType::ASIC_TYPE_RAMON:
     case cfg::AsicType::ASIC_TYPE_RAMON3:
     case cfg::AsicType::ASIC_TYPE_TOMAHAWK5:
diff --git a/fboss/agent/test/utils/ConfigUtils.cpp b/fboss/agent/test/utils/ConfigUtils.cpp
index 4913f667a9998..625bb953789b2 100644
--- a/fboss/agent/test/utils/ConfigUtils.cpp
+++ b/fboss/agent/test/utils/ConfigUtils.cpp
@@ -87,7 +87,9 @@ int getSysPortIdsAllocated(
     std::optional<PlatformType> platformType = std::nullopt) {
   auto portsConsumed = firstSwitchIdMin;
   auto deviceIndex = remoteSwitchId / asic.getNumCores();
-  CHECK(asic.getAsicType() == cfg::AsicType::ASIC_TYPE_JERICHO3);
+  CHECK(
+      asic.getAsicType() == cfg::AsicType::ASIC_TYPE_JERICHO3 ||
+      asic.getAsicType() == cfg::AsicType::ASIC_TYPE_Q4D);
   if (deviceIndex < getMaxRdsw(platformType)) {
     portsConsumed += deviceIndex * getRdswSysPortBlockSize(platformType) - 1;
   } else {
diff --git a/fboss/agent/test/utils/CoppTestUtils.cpp b/fboss/agent/test/utils/CoppTestUtils.cpp
index 3335aec4ce3cb..1016ca276fa96 100644
--- a/fboss/agent/test/utils/CoppTestUtils.cpp
+++ b/fboss/agent/test/utils/CoppTestUtils.cpp
@@ -119,6 +119,7 @@ uint16_t getCoppHighPriQueueId(const HwAsic* hwAsic) {
     case cfg::AsicType::ASIC_TYPE_YUBA:
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
     case cfg::AsicType::ASIC_TYPE_G202X:
       return 7;
     case cfg::AsicType::ASIC_TYPE_CHENAB:
@@ -166,6 +167,7 @@ cfg::ToCpuAction getCpuActionType(const HwAsic* hwAsic) {
       return cfg::ToCpuAction::COPY;
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
     case cfg::AsicType::ASIC_TYPE_CHENAB:
       return cfg::ToCpuAction::TRAP;
     case cfg::AsicType::ASIC_TYPE_ELBERT_8DD:
@@ -246,7 +248,8 @@ cfg::PortQueueRate getPortQueueRate(const HwAsic* hwAsic, uint16_t queueId) {
     portQueueRate.pktsPerSec() = getRange(0, pps);
   } else {
     uint32_t kbps;
-    if (hwAsic->getAsicType() == cfg::AsicType::ASIC_TYPE_JERICHO3) {
+    if (hwAsic->getAsicType() == cfg::AsicType::ASIC_TYPE_JERICHO3 ||
+        hwAsic->getAsicType() == cfg::AsicType::ASIC_TYPE_Q4D) {
       kbps = kCoppDnxLowPriKbitsPerSec;
     } else {
       kbps = getCoppQueueKbpsFromPps(hwAsic, pps);
diff --git a/fboss/agent/test/utils/InvariantTestUtils.cpp b/fboss/agent/test/utils/InvariantTestUtils.cpp
index cbcbe8039dc31..92d27cb81fc21 100644
--- a/fboss/agent/test/utils/InvariantTestUtils.cpp
+++ b/fboss/agent/test/utils/InvariantTestUtils.cpp
@@ -46,6 +46,7 @@ void verifySafeDiagCmds(TestEnsembleIf* ensemble) {
       case cfg::AsicType::ASIC_TYPE_AGERA3:
       case cfg::AsicType::ASIC_TYPE_JERICHO2:
       case cfg::AsicType::ASIC_TYPE_JERICHO3:
+      case cfg::AsicType::ASIC_TYPE_Q4D:
       case cfg::AsicType::ASIC_TYPE_RAMON:
       case cfg::AsicType::ASIC_TYPE_RAMON3:
       case cfg::AsicType::ASIC_TYPE_TOMAHAWK5:
diff --git a/fboss/agent/test/utils/PfcTestUtils.cpp b/fboss/agent/test/utils/PfcTestUtils.cpp
index 3602f1c841727..cf8aac4358933 100644
--- a/fboss/agent/test/utils/PfcTestUtils.cpp
+++ b/fboss/agent/test/utils/PfcTestUtils.cpp
@@ -261,6 +261,7 @@ PfcBufferParams PfcBufferParams::getPfcBufferParams(
   switch (asicType) {
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
       buffer.globalShared = kSmallGlobalSharedBytes;
       break;
     default:
diff --git a/fboss/agent/test/utils/PortTestUtils.cpp b/fboss/agent/test/utils/PortTestUtils.cpp
index 4b2be9794818a..81afcbcecef2d 100644
--- a/fboss/agent/test/utils/PortTestUtils.cpp
+++ b/fboss/agent/test/utils/PortTestUtils.cpp
@@ -186,6 +186,7 @@ cfg::PortSpeed getDefaultInterfaceSpeed(const cfg::AsicType& asicType) {
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
       return cfg::PortSpeed::HUNDREDG;
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
       return cfg::PortSpeed::FOURHUNDREDG;
     default:
       throw FbossError(
@@ -199,6 +200,7 @@ cfg::PortSpeed getDefaultFabricSpeed(const cfg::AsicType& asicType) {
     case cfg::AsicType::ASIC_TYPE_JERICHO2:
       return cfg::PortSpeed::FIFTYTHREEPOINTONETWOFIVEG;
     case cfg::AsicType::ASIC_TYPE_JERICHO3:
+    case cfg::AsicType::ASIC_TYPE_Q4D:
       return cfg::PortSpeed::HUNDREDANDSIXPOINTTWOFIVEG;
     default:
       throw FbossError(
diff --git a/fboss/lib/platform_mapping_v2/platform_mapping_config.thrift b/fboss/lib/platform_mapping_v2/platform_mapping_config.thrift
index e97a65d4ede66..9d5d0254edf26 100644
--- a/fboss/lib/platform_mapping_v2/platform_mapping_config.thrift
+++ b/fboss/lib/platform_mapping_v2/platform_mapping_config.thrift
@@ -34,6 +34,7 @@ enum CoreType {
   J3_EVT = 7, // J3 Eventor Port
   CHENAB_NIF = 8,
   TH6_NIF = 9, // TH6
+  Q4D_NIF = 10, // Q4D
 
   // Transceivers
   OSFP = 100,