diff --git a/Makefile.am b/Makefile.am
index 84b0c56..953a5ae 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -7,7 +7,7 @@
 
 libsyscmdsdir = ${libdir}/ipmid-providers
 libsyscmds_LTLIBRARIES = libsyscmds.la
-libsyscmds_la_SOURCES = main.cpp cable.cpp cpld.cpp eth.cpp psu.cpp
+libsyscmds_la_SOURCES = main.cpp cable.cpp cpld.cpp eth.cpp psu.cpp pcie_i2c.cpp
 
 libsyscmds_la_LDFLAGS = \
 	$(SDBUSPLUS_LIBS) \
diff --git a/README.md b/README.md
index 5486171..f3b7fae 100644
--- a/README.md
+++ b/README.md
@@ -93,3 +93,43 @@
 |Byte(s) |Value  |Data
 |--------|-------|----
 |0x00|0x03|Subcommand
+
+### GetPCIeSlotsCount - SubCommand 0x04 {#getpcieslotscount-0x04}
+
+Sys can get the total number of PCIe slots from BMC using this command. When BMC receives this command, BMC can enumerate over all the PCIe slots and create a hashmap with all the available PCIe slot name - I2C bus number mappings. BMC can then send the total number of PCIe slots as part of this command response.
+
+Request
+
+|Byte(s) |Value  |Data
+|--------|-------|----
+|0x00|0x04|Subcommand
+
+
+Response
+
+|Byte(s) |Value  |Data
+|--------|-------|----
+|0x00|0x04|Subcommand
+|0x01|Total number of PCIe slots|Total number of PCIe slots
+
+
+### GetPCIeSlotI2cBusMapping - SubCommand 0x05 {#getpciesloti2cbusmapping-0x05}
+
+If Sys gets N total slots as part of the above command, then Sys can send this command N times with Entry IDs ranging from 0 to N - 1. Say, Sys sends this command with Entry ID as 1, BMC can go and fetch the first PCIe slot name - I2C bus number mapping from the hashmap created above and then send the PCIe slot name and I2C bus number as part of the command response.
+
+Request
+
+|Byte(s) |Value  |Data
+|--------|-------|----
+|0x00|0x05|Subcommand
+|0x01|Entry ID|Entry ID ranging from 0 to N - 1
+
+
+Response
+
+|Byte(s) |Value  |Data
+|--------|-------|----
+|0x00|0x05|Subcommand
+|0x01|I2C bus number|The I2C bus number which is input to the above PCIe slot
+|0x02|PCIe slot name length|The PCIe slot name length
+|0x03...|PCIe slot name|The PCIe slot name without null terminator
diff --git a/main.cpp b/main.cpp
index eaa82ab..f0c61a9 100644
--- a/main.cpp
+++ b/main.cpp
@@ -19,6 +19,7 @@
 #include "cable.hpp"
 #include "cpld.hpp"
 #include "eth.hpp"
+#include "pcie_i2c.hpp"
 #include "psu.hpp"
 
 #include <host-ipmid/ipmid-api.h>
@@ -62,6 +63,10 @@
             return GetEthDevice(reqBuf, replyCmdBuf, dataLen);
         case SysPsuHardReset:
             return PsuHardReset(reqBuf, replyCmdBuf, dataLen);
+        case SysPcieSlotCount:
+            return PcieSlotCount(reqBuf, replyCmdBuf, dataLen);
+        case SysPcieSlotI2cBusMapping:
+            return PcieSlotI2cBusMapping(reqBuf, replyCmdBuf, dataLen);
         default:
             std::fprintf(stderr, "Invalid subcommand: 0x%x\n", reqBuf[0]);
             return IPMI_CC_INVALID;
diff --git a/main.hpp b/main.hpp
index f34e2a3..f1cfccf 100644
--- a/main.hpp
+++ b/main.hpp
@@ -15,6 +15,10 @@
     SysGetEthDevice = 2,
     // The Sys psu hard reset command.
     SysPsuHardReset = 3,
+    // The Sys pcie slot count command.
+    SysPcieSlotCount = 4,
+    // The Sys pcie slot to i2c bus mapping command.
+    SysPcieSlotI2cBusMapping = 5,
 };
 
 } // namespace ipmi
diff --git a/pcie_i2c.cpp b/pcie_i2c.cpp
new file mode 100644
index 0000000..80d545a
--- /dev/null
+++ b/pcie_i2c.cpp
@@ -0,0 +1,227 @@
+/*
+ * Copyright 2018 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "pcie_i2c.hpp"
+
+#include "main.hpp"
+
+#include <cstdint>
+#include <cstring>
+#include <experimental/filesystem>
+#include <fstream>
+#include <regex>
+#include <sstream>
+#include <string>
+#include <system_error>
+#include <unordered_map>
+
+namespace google
+{
+namespace ipmi
+{
+namespace fs = std::experimental::filesystem;
+
+namespace
+{
+
+#ifndef MAX_IPMI_BUFFER
+#define MAX_IPMI_BUFFER 64
+#endif
+
+std::vector<std::tuple<uint32_t, std::string>> pcie_i2c_map;
+
+std::string read_file(const std::string& file_name)
+{
+    std::ifstream ifs(file_name);
+    std::string file_content;
+    if (!ifs.is_open())
+    {
+        std::fprintf(stderr, "Unable to open file %s.\n", file_name.c_str());
+    }
+    else
+    {
+        if (ifs >> file_content)
+        {
+            // If the last character is a null terminator; remove it.
+            if (!file_content.empty())
+            {
+                char const& back = file_content.back();
+                if (back == '\0')
+                    file_content.pop_back();
+            }
+            return file_content;
+        }
+        else
+        {
+            std::fprintf(stderr, "Unable to read file %s.\n",
+                         file_name.c_str());
+        }
+    }
+    return "";
+}
+
+} // namespace
+
+struct PcieSlotCountRequest
+{
+    uint8_t subcommand;
+} __attribute__((packed));
+
+struct PcieSlotCountReply
+{
+    uint8_t subcommand;
+    uint8_t value;
+} __attribute__((packed));
+
+struct PcieSlotI2cBusMappingRequest
+{
+    uint8_t subcommand;
+    uint8_t entry;
+} __attribute__((packed));
+
+struct PcieSlotI2cBusMappingReply
+{
+    uint8_t subcommand;
+    uint8_t i2c_bus_number;
+    uint8_t pcie_slot_name_len;
+    uint8_t pcie_slot_name[0];
+} __attribute__((packed));
+
+ipmi_ret_t PcieSlotCount(const uint8_t* reqBuf, uint8_t* replyBuf,
+                         size_t* dataLen)
+{
+    if ((*dataLen) < sizeof(struct PcieSlotCountRequest))
+    {
+        std::fprintf(stderr, "Invalid command length: %u\n",
+                     static_cast<uint32_t>(*dataLen));
+        return IPMI_CC_REQ_DATA_LEN_INVALID;
+    }
+
+    // If there are already entries in the vector, clear them.
+    if (!pcie_i2c_map.empty())
+        pcie_i2c_map.clear();
+
+    // Build a vector with i2c bus to pcie slot mapping.
+    // Iterate through all the devices under "/sys/bus/i2c/devices".
+    for (auto& i2c_dev : fs::directory_iterator("/sys/bus/i2c/devices"))
+    {
+        std::string i2c_dev_path = i2c_dev.path();
+        std::smatch i2c_dev_string_number;
+        std::regex e("(i2c-)(\\d+)");
+        // Check if the device has "i2c-" in its path.
+        if (std::regex_search(i2c_dev_path, i2c_dev_string_number, e))
+        {
+            // Check if the i2c device has "pcie-slot" file under "of-node" dir.
+            std::string pcie_slot_path = i2c_dev_path + "/of_node/pcie-slot";
+            std::string pcie_slot;
+            // Read the "pcie-slot" name from the "pcie-slot" file.
+            pcie_slot = read_file(pcie_slot_path);
+            if (pcie_slot.empty())
+            {
+                continue;
+            }
+            std::string pcie_slot_name;
+            std::string pcie_slot_full_path;
+            // Append the "pcie-slot" name to dts base.
+            pcie_slot_full_path.append("/proc/device-tree");
+            pcie_slot_full_path.append(pcie_slot);
+            // Read the "label" which contains the pcie slot name.
+            pcie_slot_full_path.append("/label");
+            pcie_slot_name = read_file(pcie_slot_full_path);
+            if (pcie_slot_name.empty())
+            {
+                continue;
+            }
+            // Get the i2c bus number from the i2c device path.
+            uint32_t i2c_bus_number = i2c_dev_string_number[2].matched
+                                          ? std::stoi(i2c_dev_string_number[2])
+                                          : 0;
+            // Store the i2c bus number and the pcie slot name in the vector.
+            pcie_i2c_map.push_back(
+                std::make_tuple(i2c_bus_number, pcie_slot_name));
+        }
+    }
+
+    struct PcieSlotCountReply reply;
+    reply.subcommand = SysPcieSlotCount;
+    // Fill the pcie slot count as the number of entries in the vector.
+    reply.value = pcie_i2c_map.size();
+
+    std::memcpy(&replyBuf[0], &reply, sizeof(reply));
+
+    // Return the subcommand and the result.
+    (*dataLen) = sizeof(reply);
+
+    return IPMI_CC_OK;
+}
+
+ipmi_ret_t PcieSlotI2cBusMapping(const uint8_t* reqBuf, uint8_t* replyBuf,
+                                 size_t* dataLen)
+{
+    struct PcieSlotI2cBusMappingRequest request;
+
+    if ((*dataLen) < sizeof(request))
+    {
+        std::fprintf(stderr, "Invalid command length: %u\n",
+                     static_cast<uint32_t>(*dataLen));
+        return IPMI_CC_REQ_DATA_LEN_INVALID;
+    }
+
+    // If there are no entries in the vector return error.
+    if (pcie_i2c_map.empty())
+    {
+        return IPMI_CC_INVALID_RESERVATION_ID;
+    }
+
+    std::memcpy(&request, &reqBuf[0], sizeof(request));
+
+    // The valid entries range from 0 to N - 1, N being the total number of
+    // entries in the vector.
+    if (request.entry >= pcie_i2c_map.size())
+    {
+        return IPMI_CC_PARM_OUT_OF_RANGE;
+    }
+
+    // Get the i2c bus number and the pcie slot name from the vector.
+    uint32_t i2c_bus_number = std::get<0>(pcie_i2c_map[request.entry]);
+    std::string pcie_slot_name = std::get<1>(pcie_i2c_map[request.entry]);
+
+    int length =
+        sizeof(struct PcieSlotI2cBusMappingReply) + pcie_slot_name.length();
+
+    // TODO (jaghu) : Add a way to dynamically receive the MAX_IPMI_BUFFER
+    // value and change error to IPMI_CC_REQUESTED_TOO_MANY_BYTES.
+    if (length > MAX_IPMI_BUFFER)
+    {
+        std::fprintf(stderr, "Response would overflow response buffer\n");
+        return IPMI_CC_INVALID;
+    }
+
+    auto reply =
+        reinterpret_cast<struct PcieSlotI2cBusMappingReply*>(&replyBuf[0]);
+    reply->subcommand = SysPcieSlotI2cBusMapping;
+    // Copy the i2c bus number and the pcie slot name to the reply struct.
+    reply->i2c_bus_number = i2c_bus_number;
+    reply->pcie_slot_name_len = pcie_slot_name.length();
+    std::memcpy(reply->pcie_slot_name, pcie_slot_name.c_str(),
+                pcie_slot_name.length());
+
+    // Return the subcommand and the result.
+    (*dataLen) = length;
+    return IPMI_CC_OK;
+}
+} // namespace ipmi
+} // namespace google
diff --git a/pcie_i2c.hpp b/pcie_i2c.hpp
new file mode 100644
index 0000000..6150226
--- /dev/null
+++ b/pcie_i2c.hpp
@@ -0,0 +1,21 @@
+#pragma once
+
+#include <host-ipmid/ipmid-api.h>
+
+namespace google
+{
+namespace ipmi
+{
+
+//  Handle the pcie slot count command.
+//  Sys can query the number of pcie slots.
+ipmi_ret_t PcieSlotCount(const uint8_t* reqBuf, uint8_t* replyBuf,
+                         size_t* dataLen);
+
+// Handle the pcie slot to i2c bus mapping command.
+// Sys can query which i2c bus is routed to which pcie slot.
+ipmi_ret_t PcieSlotI2cBusMapping(const uint8_t* reqBuf, uint8_t* replyBuf,
+                                 size_t* dataLen);
+
+} // namespace ipmi
+} // namespace google