diff --git a/LICENSE.txt b/LICENSE.txt
new file mode 100644
index 0000000..9276d43
--- /dev/null
+++ b/LICENSE.txt
@@ -0,0 +1,22 @@
+MIT License
+
+Copyright (c) 2018 Shotaro Gotanda, Masashi Ikarashi
+https://github.com/progrunner17/e1000/blob/master/LICENSE.txt
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..8e402f3
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,70 @@
+CC = gcc
+CFLAGS = -g -MMD -MP -Wall -Werror=implicit -pthread -std=gnu99
+SRCS = main.c init.c util.c mem.c reg.c desc.c
+LIBS = checker.a
+OBJS = $(SRCS:.c=.o)
+DEPS= $(filter %.d, $(subst .o,.d, $(OBJS)))
+TARGET = driver
+
+
+TARGET_KEYWORD := I217
+TARGET_DEFAULT_DRIVER := e1000e
+TARGET_PCI_BUS_ID:=$(if $(TARGET_PCI_BUS_ID),$(TARGET_PCI_BUS_ID),$(shell lspci -D | grep $(TARGET_KEYWORD) | cut -f 1 -d ' ' | head -n1))
+TARGET_PCI_VID_DID=$(shell lspci -n -s $(TARGET_PCI_BUS_ID) | cut -f 3 -d ' ')
+TARGET_PCI_VID=$(shell echo $(TARGET_PCI_VID_DID) | cut -f 1 -d ':')
+TARGET_PCI_DID=$(shell echo $(TARGET_PCI_VID_DID) | cut -f 2 -d ':')
+TARGET_CURRENT_DRIVER=$(shell lspci -k -s $(TARGET_PCI_BUS_ID) | grep "Kernel driver in use:" | cut -f 2 -d ":" | tr -d " ")
+
+ARGS=
+
+
+
+default: $(TARGET)
+
+.PHONY: load restore run exec
+
+-include $(DEPS)
+
+run:load
+	trap '$(MAKE) restore;' INT ; $(MAKE) exec ; $(MAKE) restore;
+
+exec: $(TARGET)
+	sudo sh -c "echo 120 > /proc/sys/vm/nr_hugepages"
+	sudo ./$(TARGET) $(ARGS)
+
+
+check:
+	@lspci -vvxxx -n -k -s $(TARGET_PCI_BUS_ID)
+	@echo "           bus: $(TARGET_PCI_BUS_ID)"
+	@echo "        vendor: $(TARGET_PCI_VID)"
+	@echo "        device: $(TARGET_PCI_DID)"
+	@echo "driver current: $(TARGET_CURRENT_DRIVER)"
+	@echo "       default: $(TARGET_DEFAULT_DRIVER)"
+
+load:
+ifneq ($(shell lspci -v -s $(TARGET_PCI_BUS_ID) | grep $(TARGET_DEFAULT_DRIVER)),)
+	sudo modprobe uio_pci_generic
+	sudo sh -c "echo '$(TARGET_PCI_VID) $(TARGET_PCI_DID)' > /sys/bus/pci/drivers/uio_pci_generic/new_id"
+	sudo sh -c "echo -n $(TARGET_PCI_BUS_ID) > /sys/bus/pci/drivers/$(TARGET_CURRENT_DRIVER)/unbind"
+	sudo sh -c "echo -n $(TARGET_PCI_BUS_ID) > /sys/bus/pci/drivers/uio_pci_generic/bind"
+endif
+
+restore:
+ifeq ($(shell lspci -v -s $(TARGET_PCI_BUS_ID) | grep $(TARGET_DEFAULT_DRIVER)),)
+	sudo modprobe $(TARGET_DEFAULT_DRIVER)
+	sudo sh -c "echo -n $(TARGET_PCI_BUS_ID) > /sys/bus/pci/drivers/$(TARGET_CURRENT_DRIVER)/unbind"
+	sudo sh -c "echo -n $(TARGET_PCI_BUS_ID) > /sys/bus/pci/drivers/$(TARGET_DEFAULT_DRIVER)/bind"
+endif
+
+
+watch_irq:
+	watch -n1 "cat /proc/interrupts"
+
+
+
+$(TARGET): $(OBJS) $(LIBS)
+	$(CC) $(CFLAGS) -o $@ $^
+
+
+clean:
+	$(RM) $(TARGET) $(OBJS) $(DEPS) *~
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..f106a2a
--- /dev/null
+++ b/README.md
@@ -0,0 +1,18 @@
+# e1000
+
+e1000e向けのデバイスドライバ
+
+## 使用方法
+- `make run`
+  - プログラムの実行
+- `make check`
+  - デバイスの状態チェック
+- `make clean`
+
+## PCに不調が出たら
+`make check`で「driver current」と「default」がどちらもe1000eであることを確認してください  
+万が一「driver current」がuio_pci_genericとなっていた場合`make restore`を実行して下さい。
+
+それでも直らない場合はPCを再起動してください。
+
+
diff --git a/checker.a b/checker.a
new file mode 100644
index 0000000..c1804ec
Binary files /dev/null and b/checker.a differ
diff --git a/checker.h b/checker.h
new file mode 100644
index 0000000..df9399c
--- /dev/null
+++ b/checker.h
@@ -0,0 +1,23 @@
+#define CHECK_LEVEL ((check_level)CHECK_STRICT)
+
+#include <stdint.h>
+
+// Define check level.
+// When CHECK_NONE, these functions do nothing.
+#define CHECK_STRICT 2
+#define CHECK_LOOSE  1
+#define CHECK_NONE   0
+
+typedef int check_level;
+
+
+void check_set_rqueue_head(check_level l, uint32_t val);
+void check_set_tqueue_head(check_level l, uint32_t val);
+void check_set_rqueue_tail(check_level l, uint32_t val);
+void check_set_tqueue_tail(check_level l, uint32_t val);
+void check_before_rqueue_enable(check_level l);
+void check_before_tqueue_enable(check_level l);
+void check_before_set_rdba(check_level l);
+void check_before_set_tdba(check_level l);
+void check_before_set_rdlen(check_level l);
+void check_before_set_tdlen(check_level l);
diff --git a/desc.c b/desc.c
new file mode 100644
index 0000000..7f1d33a
--- /dev/null
+++ b/desc.c
@@ -0,0 +1,30 @@
+#include <stdio.h>
+#include <stdint.h>
+#include "mem.h"
+#define DANGER
+#include "reg.h"
+#include "desc.h"
+#include "checker.h"
+
+uint64_t get_mac_addr(void) {
+  static uint64_t mac_addr = 0;
+  if (mac_addr == 0) {
+    uint32_t buf32;
+    buf32 = read_reg_wrapper(RAL_OFFSET);
+    mac_addr |= buf32;
+    buf32 = read_reg_wrapper(RAH_OFFSET);
+    mac_addr |= ((uint64_t)buf32 & 0xFFFFll) << 32;
+  }
+  return mac_addr;
+}
+
+void enable_receive(void) {
+  check_before_rqueue_enable(CHECK_LEVEL);
+  set_flags((uint32_t)RCTL_OFFSET, (uint32_t)RCTL_EN);
+}
+void enable_transmit(void) {
+  check_before_tqueue_enable(CHECK_LEVEL);
+  set_flags((uint32_t)TCTL_OFFSET, (uint32_t)TCTL_EN);
+}
+void disable_receive(void) { clear_flags((uint32_t)RCTL_OFFSET, (uint32_t)RCTL_EN); }
+void disable_transmit(void) { clear_flags((uint32_t)TCTL_OFFSET, (uint32_t)TCTL_EN); }
diff --git a/desc.h b/desc.h
new file mode 100644
index 0000000..15622c8
--- /dev/null
+++ b/desc.h
@@ -0,0 +1,47 @@
+#pragma once
+#include "mem.h"
+uint64_t get_mac_addr(void);
+void enable_receive(void);
+void enable_transmit(void);
+void disable_receive(void);
+void disable_transmit(void);
+
+/* Receive Descriptor
+** Legacy Rx Descriptor (RCTL.DTYPE=00b,RFCTL.EXSTEN = 0b)
+** see spec p23 3.2.4 Receive Descriptor Format
+** 命名規則は基本的にはspec依存
+** 例外
+** buffer address -> addr
+** packet checksum -> csm
+** vlan tag -> vtag
+*/
+typedef struct rdesc *Rdesc;
+struct rdesc {
+  phys_addr addr;
+  uint16_t length;
+  uint16_t csm;
+  uint8_t status;
+  uint8_t errors;
+  uint16_t vtag;
+}__attribute__((packed));
+
+/* Transmit Descriptor
+** Legacy Transmit Descriptor (デスクリプタのdext ＝ 1bで設定)
+** こちらの命名規則も基本的にはspec準拠
+** その結果ステータスがstaとなっていたりする。(Rxではstatus)
+** reserved はstaにまとめた。
+**
+*/
+
+typedef struct tdesc *Tdesc;
+struct tdesc {
+  phys_addr addr;
+  uint16_t length;
+  uint8_t cso;
+  uint8_t cmd;
+  uint8_t sta;
+  uint8_t css;
+  uint16_t special;
+}__attribute__((packed));
+
+
diff --git a/init.c b/init.c
new file mode 100644
index 0000000..53c3553
--- /dev/null
+++ b/init.c
@@ -0,0 +1,155 @@
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/uio.h>
+#include <unistd.h>
+
+#include "init.h"
+#include "util.h"
+#define DANGER
+#include "reg.h"
+#undef DANGER
+
+void init_pci() {
+  int uiofd, configfd, csrfd;
+  uint16_t buf16;
+
+  uiofd = open("/dev/uio0", O_RDONLY);
+  if (uiofd < 0) {
+    perror("uio open:");
+    panic("");
+  }
+  print_log("open /dev/uio0");
+
+  configfd = open("/sys/class/uio/uio0/device/config", O_RDWR);
+  if (configfd < 0) {
+    perror("config open:");
+    panic("");
+  }
+  print_log("[init_pci] open /sys/class/uio/uio0/device/config");
+
+  // PCICMD see chipset c220 spec p365
+  // Bus Master Enable, Memory Space Enable, I/O Space Enable
+  pread(configfd, &buf16, 2, 0x04);
+  buf16 |= 0b111;
+  pwrite(configfd, &buf16, 2, 0x04);
+  print_log("config PCIe CTRL register");
+
+  csrfd = open("/sys/class/uio/uio0/device/resource0", O_RDWR);
+  if (csrfd < 0) {
+    perror("open");
+    panic("");
+  }
+  print_log("[init_pci] open resource0");
+
+  // Internal registers and memories region is 128KB
+  // see spec Table 13-1 PCI Base Address Registers (p271)
+  void *base_addr =
+      mmap(NULL, 1 << 17, PROT_READ | PROT_WRITE, MAP_SHARED, csrfd, 0);
+  if (base_addr == MAP_FAILED) {
+    perror("mmap");
+    panic("");
+  }
+  set_regspace(base_addr);
+  close(csrfd);
+  print_log("[init_pci] map Internal registers and memories(resource0)");
+  print_log("[init_pci] regspace = %p", base_addr);
+}
+
+void init_dev(void) {
+  uint16_t buf16;
+
+  // Disable Interrupts;
+  // see spec 14.4 Interrupts Duraing Initialization
+  // cf. spec 13.3.32 Interrupt Mask Clear Register
+  set_flags(IMC_OFFSET, 0xFFFFFFFF);
+
+  print_log("[init_dev] Disable interrupts");
+  usleep(10000);
+  print_log("wait 10ms");
+
+  // Global reset
+  // see spec chapter 14.5(p490)
+  // CHECK: are these really Global reset?
+  set_flags(CTRL_OFFSET, CTRL_LRST | CTRL_RST | CTRL_PHY_RST);
+  print_log("[init_dev] Global rest(Link reset & Device reset & PHY reset)");
+
+  // Disable Interrupts again;
+  // see spec 14.4 Interrupts Duraing Initialization
+  set_flags(IMC_OFFSET, 0xFFFFFFFF);
+  print_log("[init_dev] Disable interrupt(again)");
+
+  // General Configuration
+  // see spec 14.5 Global Reset and General Configuration
+  // there seems to be device specific setting (ignore them here)
+  // No use of XOFF flow control write 0 to FCAL, FCAH, FCT
+  write_reg(FCAL_OFFSET, 0);
+  write_reg(FCAH_OFFSET, 0);
+  write_reg(FCT_OFFSET, 0);
+  print_log("[init_dev] Configure XOFF Flow control(no use)");
+
+  // Setup PHY and Link
+  // see spec 14.8 Link Setup Mechanisms and Control/Status Bit Summary
+
+  // PHY Initialization
+  // see spec 14.8.1 PHY Initialization
+  // see spec 13.3.8 MDI Control Register
+  buf16 = read_mdic(MDIC_PCTRL_POFFSET);
+  buf16 |= MDIC_PCTRL_PHYRST;
+  write_mdic(MDIC_PCTRL_POFFSET, buf16);
+  print_log("[init_dev] PHY RESET from MDI");
+
+  // MAC/PHY Link Setup
+  // see spec 14.8.2 MAC/PHY Link Setup
+  clear_flags(CTRL_OFFSET, CTRL_FRCSPD | CTRL_FRCDPLX);
+  set_flags(CTRL_OFFSET, CTRL_SLU | CTRL_RFCE);
+  print_log("[init_dev] MAC/PHY Link Setup");
+
+  // Initialize all statistical counters
+  // see spec 13.9 Statistics Registers
+  // dee spec 14.10 Initialization of Statistics
+  usleep(1000);
+  for (int offset = 0x04000; offset <= 0x04124; offset += 0x04) {
+    read_reg(offset);
+  }
+  print_log("[init_dev] reset statistical registers");
+}
+
+void init_receive(void) {
+  // see spec 14.6 Receive Initialization
+
+  // MTA
+  // see spec 13.4.1 Multicast Table Array
+  for (int i = 0; i < MTA_LEN; i++) {
+    write_reg(MTA_OFFSET + i * 4, 0);
+  }
+  print_log("[Receive] Reset Multicast Table Array");
+
+  // RCTL
+  // see spec 13.3.34 Receive Control Register
+  // set receive buffer size to 2KB & disable VFE
+  clear_flags(RCTL_OFFSET, RCTL_BSIZE_MASK | RCTL_BSEX | RCTL_VFE);
+  set_flags(RCTL_OFFSET, RCTL_BSIZE_2K | RCTL_UPE | RCTL_MPE |RCTL_LPE);
+  print_log("[Receive] program RCTL");
+}
+
+void init_transmit(void) {
+  // TXDCTL values GRAN=1 WTHRESH=1(TXDCTL[21:16]) othes=0
+  write_reg(TXDCTL_OFFSET, TXDCTL_GRAN | (1 << 16));
+  print_log("[Transmit] program TXDCTL");
+
+  // TCTL CT=0x0F(TCTL[11:4]) COLD=0x03F(TCTL[21:12]) PSP=1b EN =1b others = 0
+  write_reg(TCTL_OFFSET, (0x0F << 4) | (0x03F << 12) | TCTL_PSP);
+  print_log("[Transmit] program TCTL");
+
+  // Program TARC if use multi Txqueues
+  // TODO:
+
+  // Program TIPG
+  // TODO:
+}
+
+void disable_interrupts(uint32_t flags) { set_flags(IMC_OFFSET, flags); }
+void enable_interrupts(uint32_t flags) { set_flags(IMS_OFFSET, flags); }
diff --git a/init.h b/init.h
new file mode 100644
index 0000000..a620bee
--- /dev/null
+++ b/init.h
@@ -0,0 +1,8 @@
+#pragma once
+// pciを初期化
+void init_pci(void);
+void init_dev(void);
+void init_receive(void);
+void init_transmit(void);
+void enable_interrupts(uint32_t);
+void disable_interrupts(uint32_t);
diff --git a/main.c b/main.c
new file mode 100644
index 0000000..56eeb76
--- /dev/null
+++ b/main.c
@@ -0,0 +1,47 @@
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include "desc.h"
+#include "init.h"
+#include "mem.h"
+#include "reg.h"
+#include "util.h"
+
+int main(int argc, char const *argv[]) {
+  init_pci();
+  init_dev();
+  init_mem(1024 * 1024 * 2);
+
+  void *memory_base_virt = get_virt_ptr();
+  size_t memory_base_phys = get_phys_ptr();
+
+  // initialize receive
+  print_log("initialize receive");
+  init_receive();
+  // TODO: set receive descriptor ring base address and length
+
+  // receive buffer size is set to 2KB in init_receive
+  // TODO: allocate memory to each receivev descriptors
+
+  enable_receive();
+
+  // initialize transmit
+  print_log("initialize transmit");
+  init_transmit();
+  // TODO: set transmit descriptor ring base address and length
+
+  // TODO: allocate memory to each transmit descriptors
+  // this can be done on transmit
+
+  enable_transmit();
+  print_log("enable interrupts");
+  enable_interrupts(0xFFFFFFFF);
+  usleep(1000);
+
+  // TODO: program data communicaton
+
+  // wait until NIC send packet physically 
+  sleep(2);
+  return 0;
+}
diff --git a/mem.c b/mem.c
new file mode 100644
index 0000000..5d2796a
--- /dev/null
+++ b/mem.c
@@ -0,0 +1,63 @@
+#include <assert.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include "mem.h"
+#include "util.h"
+
+size_t v2p(size_t vaddr);
+static virt_addr _virt;
+static phys_addr _phys;
+static size_t _req_size = 0;
+static size_t _act_size = 0;
+
+phys_addr get_phys_ptr() { return _phys; }
+
+virt_addr get_virt_ptr() { return _virt; }
+
+void init_mem(size_t size) {
+  _req_size = size;
+
+  if (_req_size > 0) {
+    _act_size = 2 * 1024 * 1024;
+    assert(_req_size <= _act_size);
+    _virt =
+      mmap(NULL, _act_size, PROT_READ | PROT_WRITE,
+          MAP_PRIVATE | MAP_HUGETLB | MAP_ANONYMOUS | MAP_POPULATE, 0, 0);
+    if (_virt == MAP_FAILED) {
+      perror("page alloc:");
+      panic("");
+    }
+    _phys = v2p((size_t)_virt);
+  } else {
+    _virt = 0;
+    _phys = 0;
+  }
+  bzero(get_virt_ptr(), _req_size);
+}
+
+size_t v2p(size_t vaddr) {
+  FILE *pagemap;
+  size_t paddr = 0;
+  ssize_t offset = (vaddr / sysconf(_SC_PAGESIZE)) * sizeof(uint64_t);
+  uint64_t e;
+
+  // https://www.kernel.org/doc/Documentation/vm/pagemap.txt
+  if ((pagemap = fopen("/proc/self/pagemap", "r"))) {
+    if (lseek(fileno(pagemap), offset, SEEK_SET) == offset) {
+      if (fread(&e, sizeof(uint64_t), 1, pagemap)) {
+        if (e & (1ULL << 63)) {            // page present ?
+          paddr = e & ((1ULL << 55) - 1);  // pfn mask
+          paddr = paddr * sysconf(_SC_PAGESIZE);
+          // add offset within page
+          paddr = paddr | (vaddr & (sysconf(_SC_PAGESIZE) - 1));
+        }
+      }
+    }
+    fclose(pagemap);
+  }
+  return paddr;
+}
diff --git a/mem.h b/mem.h
new file mode 100644
index 0000000..e5416dc
--- /dev/null
+++ b/mem.h
@@ -0,0 +1,8 @@
+#pragma once
+
+typedef size_t phys_addr;
+typedef void *virt_addr;
+
+void init_mem(size_t size);
+phys_addr get_phys_ptr();
+virt_addr get_virt_ptr();
diff --git a/reg.c b/reg.c
new file mode 100644
index 0000000..fd7c502
--- /dev/null
+++ b/reg.c
@@ -0,0 +1,117 @@
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#define DANGER
+#include "reg.h"
+#include "checker.h"
+#include "util.h"
+
+static void *regspace;
+
+
+void set_regspace(void *addr) { regspace = addr; }
+
+uint32_t read_reg_wrapper(uint32_t off){
+  switch(off){
+    case RDBAL_OFFSET:
+    case RDBAH_OFFSET:
+    case RDLEN_OFFSET:
+    case RDH_OFFSET:
+    case RDT_OFFSET:
+    case RAL_OFFSET:
+    case RAH_OFFSET:
+    case TDBAL_OFFSET:
+    case TDBAH_OFFSET:
+    case TDLEN_OFFSET:
+    case TDH_OFFSET:
+    case TDT_OFFSET:break;
+    default:panic("this register is not allowed to access");
+  }
+   return read_reg(off);
+}
+void write_reg_wrapper(uint32_t off, uint32_t val){
+  switch(off){
+    case RDBAL_OFFSET:
+    case RDBAH_OFFSET:
+        check_before_set_rdba(CHECK_LEVEL);
+        break;
+    case RDLEN_OFFSET:
+        check_before_set_rdlen(CHECK_LEVEL);
+        break;
+    case RDH_OFFSET:
+        check_set_rqueue_head(CHECK_LEVEL, val);
+        break;
+    case RDT_OFFSET:
+        check_set_rqueue_tail(CHECK_LEVEL, val);
+        break;
+    case TDBAL_OFFSET:
+    case TDBAH_OFFSET:
+        check_before_set_tdba(CHECK_LEVEL);
+        break;
+    case TDLEN_OFFSET:
+        check_before_set_tdlen(CHECK_LEVEL);
+        break;
+    case TDH_OFFSET:
+        check_set_tqueue_head(CHECK_LEVEL, val);
+        break;
+    case TDT_OFFSET:
+        check_set_tqueue_tail(CHECK_LEVEL, val);break;
+    default:panic("this register is not allowed to access");
+  }
+  write_reg(off,val);
+}
+
+
+
+void write_reg(uint32_t off, uint32_t val) {
+  ((uint32_t *)regspace)[off / 4] = val;
+}
+uint32_t read_reg(uint32_t off) {
+  return ((uint32_t *)regspace)[off / 4];
+}
+
+void set_flags(uint32_t off, uint32_t flags) {
+  uint32_t buf32;
+  buf32 = read_reg(off);
+  buf32 |= flags;
+  write_reg(off, buf32);
+}
+void clear_flags(uint32_t off, uint32_t flags) {
+  uint32_t buf32;
+  buf32 = read_reg(off);
+  buf32 &= ~flags;
+  write_reg(off, buf32);
+}
+
+void write_mdic(uint32_t page, uint16_t val) {
+  uint32_t buf = 0;
+  buf |= val;
+  buf |= (page & ((1 << 17) - 1)) << 16;  // set Page addr
+  buf |= 1 << 21;
+  buf |= 1 << 26;  // OP = Write
+  buf = 0;
+  write_reg(MDIC_OFFSET, buf);
+  // Wait until ready
+  while (1) {
+    buf = read_reg(MDIC_OFFSET);
+    if (buf & (1 << 28)) break;
+  }
+}
+
+
+
+uint16_t read_mdic(uint32_t page) {
+  uint32_t buf = 0;
+  buf |= (page & ((1 << 17) - 1)) << 16;  // set Page addr
+  buf |= 1 << 21;
+  buf |= 1 << 27;  // OP = Read
+  write_reg(MDIC_OFFSET, buf);
+  // Wait until ready
+  buf = 0;
+  while (1) {
+    buf = read_reg(MDIC_OFFSET);
+    if (buf & (1 << 28)) break;
+  }
+  return (uint16_t)(buf & 0xFFFF);
+
+}
diff --git a/reg.h b/reg.h
new file mode 100644
index 0000000..f3dc5fa
--- /dev/null
+++ b/reg.h
@@ -0,0 +1,102 @@
+#pragma once
+#include <stdint.h>
+
+
+
+
+//===========General==========================
+#define CTRL_OFFSET 0x0000
+#define CTRL_LRST (1 << 3)
+#define CTRL_SLU (1 << 6)
+#define CTRL_FRCSPD (1 << 11)
+#define CTRL_FRCDPLX (1 << 12)
+#define CTRL_RST (1 << 26)
+#define CTRL_RFCE (1 << 27)
+#define CTRL_TFCE (1 << 28)
+#define CTRL_PHY_RST (1 << 31)
+#define STATUS_OFFSET 0x0008
+
+//================MDIC=======================
+// P means PAGE
+#define MDIC_OFFSET 0x0020
+#define MDIC_PCTRL_POFFSET 0x00
+// Auto Negotiation Enable
+#define MDIC_PCTRL_ANEN (1 << 12)
+// Enable Loopback
+#define MDIC_PCTRL_ENLB (1 << 14)
+// PHY Reset
+#define MDIC_PCTRL_PHYRST (1 << 15)
+
+//================Flow Control================
+#define FCAL_OFFSET 0x0028
+#define FCAH_OFFSET 0x002C
+#define FCT_OFFSET 0x0030
+#define FCTTV_OFFSET 0x0170
+
+//================Interrupt===================
+#define IMS_OFFSET 0x00D0
+#define IMS_RXT (1 << 7)
+#define IMS_RXO (1 << 6)
+#define IMS_RXDMT (1 << 4)
+#define IMS_RXSEQ (1 << 3)
+#define IMC_OFFSET 0x00D8
+
+//================Receive=====================
+#define RCTL_OFFSET 0x0100
+#define RCTL_EN (1 << 1)
+#define RCTL_SBP (1 << 2)  // Store Bad Packet
+#define RCTL_UPE (1 << 3)
+#define RCTL_MPE (1 << 4)
+#define RCTL_LPE (1 << 5)
+#define RCTL_DTYPE_MASK (0b11 << 10)
+#define RCTL_DTYPE_LEGACY (0b00 << 10)
+#define RCTL_DTYPE_PS (0b01 << 10)
+#define RCTL_BSIZE_MASK (0b11 << 16)
+#define RCTL_BSIZE_2K (0b00 << 16)
+#define RCTL_BSIZE_1K (0b01 << 16)
+#define RCTL_VFE (1 << 18)  // VLAN Filter Enable
+#define RCTL_BSEX (1 << 25)
+
+#define RDBAL_OFFSET 0x2800
+#define RDBAH_OFFSET 0x2804
+#define RDLEN_OFFSET 0x2808
+#define RDH_OFFSET 0x2810
+#define RDT_OFFSET 0x2818
+#define RDTR_OFFSET 0x2820
+#define RXDCTL_OFFSET 0x2828
+
+//================Transmit===================
+#define TCTL_OFFSET 0x0400
+#define TCTL_EN (1 << 1)
+#define TCTL_PSP (1 << 3)
+#define TDBAL_OFFSET 0x3800
+#define TDBAH_OFFSET 0x3804
+#define TDLEN_OFFSET 0x3808
+#define TDH_OFFSET 0x3810
+#define TDT_OFFSET 0x3818
+#define TXDCTL_OFFSET 0x3828
+#define TXDCTL_GRAN (1 << 24)
+#define TIDV_OFFSET 0x3820
+
+//================Filter Registers============
+#define MTA_OFFSET 0x5200
+#define MTA_LEN    128
+#define RAL_OFFSET 0x5400
+#define RAH_OFFSET 0x5404
+
+
+#ifdef DANGER
+void set_regspace(void *addr);
+
+uint32_t read_reg(uint32_t off);
+void write_reg(uint32_t off, uint32_t val);
+
+void set_flags(uint32_t off, uint32_t val);
+void clear_flags(uint32_t off, uint32_t val);
+
+uint16_t read_mdic(uint32_t poff);
+void write_mdic(uint32_t poff, uint16_t val);
+#endif
+
+uint32_t read_reg_wrapper(uint32_t off);
+void write_reg_wrapper(uint32_t off, uint32_t val);
\ No newline at end of file
diff --git a/util.c b/util.c
new file mode 100644
index 0000000..0967a23
--- /dev/null
+++ b/util.c
@@ -0,0 +1,58 @@
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#define DANGER
+#include "reg.h"
+
+#include "util.h"
+
+#define DUMPREG(X) {X ## _OFFSET, #X}
+struct {
+  uint32_t offset;
+  const char *name;
+} dump_regs[] = {
+  DUMPREG(CTRL),
+  DUMPREG(STATUS),
+  DUMPREG(RCTL),
+  DUMPREG(RDBAL),
+  DUMPREG(RDBAH),
+  DUMPREG(RDLEN),
+  DUMPREG(RDH),
+  DUMPREG(RDT),
+  DUMPREG(RDTR),
+  DUMPREG(RXDCTL),
+  DUMPREG(RAL),
+  DUMPREG(RAH),
+  DUMPREG(TCTL),
+  DUMPREG(TDBAL),
+  DUMPREG(TDBAH),
+  DUMPREG(TDLEN),
+  DUMPREG(TDH),
+  DUMPREG(TDT),
+  DUMPREG(TXDCTL),
+  DUMPREG(TIDV),
+};
+#undef DUMPREG
+
+void dump_registers() {
+  for(size_t i=0; i<sizeof(dump_regs)/sizeof(dump_regs[0]); i++) {
+    uint32_t val;
+    val = read_reg(dump_regs[i].offset);
+    printf("%10s(%08x): %08x\n", dump_regs[i].name, dump_regs[i].offset, val);
+  }
+}
+
+
+void panic(const char *str) {
+  fprintf(stderr, "[ERROR]:%s\n", str);
+  exit(-1);
+}
+
+void print_log(const char *format, ...) {
+  va_list arg;
+  va_start(arg, format);
+  fprintf(stderr, "[LOG]:");
+  vfprintf(stderr, format, arg);
+  fprintf(stderr, "\n");
+}
diff --git a/util.h b/util.h
new file mode 100644
index 0000000..11b3514
--- /dev/null
+++ b/util.h
@@ -0,0 +1,4 @@
+#pragma once
+void panic(const char *);
+void print_log(const char *, ...);
+void dump_registers(void);
\ No newline at end of file