diff --git a/glm_ucode_disasm/glm_ucode_disasm.py b/glm_ucode_disasm/glm_ucode_disasm.py
index d3a0813..6552ae0 100644
--- a/glm_ucode_disasm/glm_ucode_disasm.py
+++ b/glm_ucode_disasm/glm_ucode_disasm.py
@@ -112,6 +112,7 @@ g_dst_mnem += g_idq_src_dst_mnem
 g_uop_lables = {}
 g_uop_cregs = {}
 g_uop_fscp_regs = {}
+g_uop_ioregs = {}
 
 def glm_ucode_disasm_init():
     global g_opcodes
@@ -294,6 +295,11 @@ def is_uop_uret(uop):
     opcode = get_uop_opcode(uop)
     return opcode in uret_opcodes
 
+def is_uop_rw_ioport(uop):
+    rwio_opcodes = [0xd0b, 0xd0f]
+    opcode = get_uop_opcode(uop)
+    return (opcode & 0xf3f) in rwio_opcodes
+
 def get_str_uop_phys_stg_buf_ldstad_special_imms(uop, uaddr):
     str_special_imms = ()
     
@@ -684,6 +690,21 @@ def get_str_uop_uret_special_imms(uop, uaddr):
     str_special_imms += "0x%02x" % uret_idx,
     return str_special_imms
 
+def get_str_uop_rw_ioport_special_imms(uop, uaddr):
+    src0_sel = get_src0_sel(uop)
+    src1_sel = get_src1_sel(uop)
+    is_src0_imm = is_src_imm_sel(src0_sel)
+    is_src1_imm = is_src_imm_sel(src1_sel)
+    assert(not is_src1_imm)
+    
+    str_special_imms = ()
+    if is_src0_imm:
+        assert((src0_sel & 0x10) == 0)
+        special_imm = ((src0_sel & 0x07) << 13) | ((uop & 0x7c0000) >> 10) | ((uop & 0xff000000) >> 24)
+        str_special_imms += get_str_ioreg(special_imm), "$"
+    
+    return str_special_imms
+
 def get_str_uop_common_special_imms(uop, uaddr):
     special_imm = (uop & 0xff000000) >> 24
     str_special_imms = "0x%08x" % special_imm,
@@ -703,6 +724,7 @@ g_uop_special_imms_process_funcs = ( \
     (is_uop_rw_segfield, get_str_uop_rw_segfield_special_imms), \
     (is_uop_aet_trace, get_str_uop_aet_trace_special_imms), \
     (is_uop_uret, get_str_uop_uret_special_imms), \
+    (is_uop_rw_ioport, get_str_uop_rw_ioport_special_imms), \
     (is_uop_common_special_imm, get_str_uop_common_special_imms))
 
 def is_uop_special_imms(uop):
@@ -841,6 +863,11 @@ def get_str_uram_addr(uram_addr):
         return g_uop_fscp_regs[uram_addr]
     return "0x%04x" % uram_addr
 
+def get_str_ioreg(ioreg):
+    if ioreg in g_uop_ioregs:
+        return g_uop_ioregs[ioreg]
+    return "0x%04x" % ioreg
+
 def uop_disassemble(uop, uaddr):
     src0_sel = get_src0_sel(uop)
     src1_sel = get_src1_sel(uop)
@@ -1112,9 +1139,11 @@ def msrom_disasm(arrays_dump_dir):
     global g_uop_cregs
     global g_uop_lables
     global g_uop_fscp_regs
+    global g_uop_ioregs
     g_uop_lables = load_id_names_str_data("lables.txt")
     g_uop_cregs = load_id_names_str_data("cregs.txt")
     g_uop_fscp_regs = load_id_names_str_data("fscp.txt")
+    g_uop_ioregs = load_id_names_str_data("ioregs.txt")
     ucode = load_ms_array_str_data(arrays_dump_dir + "\\ms_array0.txt")
     msrom_seqwords = load_ms_array_str_data(arrays_dump_dir + "\\ms_array1.txt")
     assert(len(ucode) == len(msrom_seqwords))
diff --git a/glm_ucode_disasm/ioregs.txt b/glm_ucode_disasm/ioregs.txt
new file mode 100644
index 0000000..39c1a10
--- /dev/null
+++ b/glm_ucode_disasm/ioregs.txt
@@ -0,0 +1,4 @@
+d4: PCU_CR_PCODE_UCODE_Mailbox_Interface
+d8: PCU_CR_PCODE_UCODE_Mailbox_Data
+4900: PCU_CR_MICROCONTROLLER_CONFIGURATION
+
diff --git a/glm_ucode_disasm/lables.txt b/glm_ucode_disasm/lables.txt
index 29762ae..7cf8c17 100644
--- a/glm_ucode_disasm/lables.txt
+++ b/glm_ucode_disasm/lables.txt
@@ -13,6 +13,7 @@
 0738: sysexit_xlat
 0788: rdtscp_xlat
 0794: clear_aflags_uend0
+07b5: send_op_pcu_mailbox
 0818: hlt_xlat
 0890: mov_cr0_r64_xlat
 08c0: rsm_xlat
@@ -69,6 +70,7 @@
 556a: calc_fast_sha256_start
 5795: rsa_signing_error
 5c01: probe_mode_force_smm_xlat
+5c62: send_op_data_pcu_mailbox
 5e68: fit_process_error
 5ed5: rc4_decrypt
 608a: fit_load_end