--- /dev/null
+.. SPDX-License-Identifier: GPL-2.0
+
+=======================================
+QLogic QLGE 10Gb Ethernet device driver
+=======================================
+
+This driver use drgn and devlink for debugging.
+
+Dump kernel data structures in drgn
+-----------------------------------
+
+To dump kernel data structures, the following Python script can be used
+in drgn:
+
+.. code-block:: python
+
+       def align(x, a):
+           """the alignment a should be a power of 2
+           """
+           mask = a - 1
+           return (x+ mask) & ~mask
+
+       def struct_size(struct_type):
+           struct_str = "struct {}".format(struct_type)
+           return sizeof(Object(prog, struct_str, address=0x0))
+
+       def netdev_priv(netdevice):
+           NETDEV_ALIGN = 32
+           return netdevice.value_() + align(struct_size("net_device"), NETDEV_ALIGN)
+
+       name = 'xxx'
+       qlge_device = None
+       netdevices = prog['init_net'].dev_base_head.address_of_()
+       for netdevice in list_for_each_entry("struct net_device", netdevices, "dev_list"):
+           if netdevice.name.string_().decode('ascii') == name:
+               print(netdevice.name)
+
+       ql_adapter = Object(prog, "struct ql_adapter", address=netdev_priv(qlge_device))
+
+The struct ql_adapter will be printed in drgn as follows,
+
+    >>> ql_adapter
+    (struct ql_adapter){
+            .ricb = (struct ricb){
+                    .base_cq = (u8)0,
+                    .flags = (u8)120,
+                    .mask = (__le16)26637,
+                    .hash_cq_id = (u8 [1024]){ 172, 142, 255, 255 },
+                    .ipv6_hash_key = (__le32 [10]){},
+                    .ipv4_hash_key = (__le32 [4]){},
+            },
+            .flags = (unsigned long)0,
+            .wol = (u32)0,
+            .nic_stats = (struct nic_stats){
+                    .tx_pkts = (u64)0,
+                    .tx_bytes = (u64)0,
+                    .tx_mcast_pkts = (u64)0,
+                    .tx_bcast_pkts = (u64)0,
+                    .tx_ucast_pkts = (u64)0,
+                    .tx_ctl_pkts = (u64)0,
+                    .tx_pause_pkts = (u64)0,
+                    ...
+            },
+            .active_vlans = (unsigned long [64]){
+                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 52780853100545, 18446744073709551615,
+                    18446619461681283072, 0, 42949673024, 2147483647,
+            },
+            .rx_ring = (struct rx_ring [17]){
+                    {
+                            .cqicb = (struct cqicb){
+                                    .msix_vect = (u8)0,
+                                    .reserved1 = (u8)0,
+                                    .reserved2 = (u8)0,
+                                    .flags = (u8)0,
+                                    .len = (__le16)0,
+                                    .rid = (__le16)0,
+                                    ...
+                            },
+                            .cq_base = (void *)0x0,
+                            .cq_base_dma = (dma_addr_t)0,
+                    }
+                    ...
+            }
+    }
+
+coredump via devlink
+--------------------
+
+
+And the coredump obtained via devlink in json format looks like,
+
+.. code:: shell
+
+       $ devlink health dump show DEVICE reporter coredump -p -j
+       {
+           "Core Registers": {
+               "segment": 1,
+               "values": [ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 ]
+           },
+           "Test Logic Regs": {
+               "segment": 2,
+               "values": [ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 ]
+           },
+           "RMII Registers": {
+               "segment": 3,
+               "values": [ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 ]
+           },
+           ...
+           "Sem Registers": {
+               "segment": 50,
+               "values": [ 0,0,0,0 ]
+           }
+       }
+
+When the module parameter qlge_force_coredump is set to be true, the MPI
+RISC reset before coredumping. So coredumping will much longer since
+devlink tool has to wait for 5 secs for the resetting to be
+finished.