---
layout: default
title: Lenovo T480s Maximized
permalink: /T480s-maximized-flashing/
nav_order: 8
parent: Step 2 - Flashing Guides
grand_parent: Installing and configuring
---

Lenovo T480s (Maximized)
===
<details open markdown="block">
  <summary>
    Table of contents
  </summary>
  {: .text-delta }
1. TOC
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</details> 

## ⚠️ EOL: No microcode updates
{: .warning }
This board's CPU generation has reached End of Servicing Updates.
See [per-board EOL/ESU status](https://github.com/linuxboot/heads/blob/master/doc/BOARDS_AND_TESTERS.md#per-board-eolesu-status)
for ESU dates and [Heads threat model]({{ site.baseurl }}/Heads-threat-model/#binary-blobs-microcode-updates-and-transient-execution-vulnerabilities)
for security implications.

## 🛡️ VULNERABLE: TPM GPIO Reset
{: .critical }

TPMTOTP/HOTP bypassable. Disk encryption with passphrase unaffected.
See [Per-Board Protection Status]({{ site.baseurl }}/Heads-threat-model/#per-board-protection-status),
[TPM GPIO Reset Vulnerability](https://github.com/linuxboot/heads/blob/master/doc/TPM_GPIO_Reset_Vulnerability.md).



## ⚡ Safety First

**Before starting, please read our [SPI Programmer Best Practices guide]({{ site.baseurl }}/SPI-Programmer-Best-Practices/) for essential safety information and programmer recommendations.**

[T480s Hardware Maintenance Manual](https://download.lenovo.com/pccbbs/mobiles_pdf/t480s-hmm_en.pdf)  

Accessing and flashing the BIOS chip on a T-series machine has never been easier. The process is straightforward and takes approximately 10 minutes.

The ThinkPad T480s has two SPI flash chips important for the port. The first chip holds the BIOS, ME, etc., while the second holds the Thunderbolt firmware. To access these chips, you only need to remove the back panel, which is secured by six screws. 

For whole procedure you will need: 
- A Phillips screwdriver +1 (PH1), which is standard for most laptop screws.
- A SPI programmer (recommended: Tigard; budget: CH347F or CH341A rev1.6+). For programmer-specific safety and example commands, see the [SPI Programmer Best Practices]({{ site.baseurl }}/SPI-Programmer-Best-Practices/). Using Raspberry Pi Pico as an example is described in the [Libreboot flash guide](https://libreboot.org/docs/install/spi.html).
- Other laptop/PC with a Linux-based OS installed.  
- Optional: A plastic guitar pick or an old credit card to help detach the bottom case from the clips holding it in place. Otherwise, it can be difficult to remove, increasing the risk of breaking the tabs or the top part of the bottom case above the battery connector.

There is still debate over which programmer and software should be used (flashprog vs. flashrom). Before following this guide, make sure you read [README.md](https://github.com/linuxboot/heads/tree/master/blobs/xx80/README.md) and the related information.

Some ThinkPad T480s units on the used market, like the T480, are affected by an Intel bug in the Thunderbolt firmware. In short, the flash chip becomes full, causing Thunderbolt fast charging to stop working, though slow charging still functions. This issue can also affect the USB-C port. For convenience, Heads provides a fixed and padded Thunderbolt firmware that resolves the "charging problem" if your laptop is affected. Board testers did not encounter this issue, and it is unlikely to occur if your laptop was in use for more than 12 months before flashing. If you do experience the "charging bug," it is possible to fix it with external flashing. Also, the update is possible prior flashing heads using [fwupd from a Linux distribution](https://www.reddit.com/r/thinkpad/comments/12tf6xv/psa_t480_thunderbolt_controller_v23_is_now_on/)


Before flashing heads, it is advisable to update the EC Firmware on the laptop. Some old EC firmware may be vulnerable to some serious CVEs. See [Heads-threat-model]({{ site.baseurl }}/Heads-threat-model/#binary-blobs-microcode-updates-and-transient-execution-vulnerabilities) for additional information.

The only way to update the EC Firmware, called ECP (Embedded Controller Program) by Lenovo, is to use their proprietary BIOS Update utility which typically requires a Windows system. However, you can use the BIOS Update .iso file to create a bootable USB to boot directly into the BIOS Update Utility by using geteltorito.

Locate the latest Bootable CD (.iso) file from lenovo: [BIOS Update (Bootable CD)](https://pcsupport.lenovo.com/us/en/products/laptops-and-netbooks/thinkpad-t-series-laptops/thinkpad-t480s-type-20l7-20l8/downloads/ds502226)

As of writting, the latest T480s BIOS Update is n22ur40w.iso (v1.60) published on April 16th, 2025 (so the following wget command could be oudated).

```shell
wget https://download.lenovo.com/pccbbs/mobiles/n22ur40w.iso
```

Acquire the geteltorito script. On debian, the genisoimage package contains geteltorito:
```shell
sudo apt install genisoimage
```

Generate a bootable image from the .iso:
```shell
geteltorito -o t480s_bootable_update_utility.img n22ur40w.iso
```

Write the resulting image to a USB Flash drive:
```shell
sudo dd if=t480s_bootable_update_utility.img of=/dev/sdX status=progress
```

Boot from the USB on the laptop and follow the update prompts.

## Disassembly

First, disconnect the power cable from your device then begin removing the back panel by removing the screws. A guitar pick or an old credit card can be helpful for detaching the panel.

![Back view]({{ site.baseurl }}/images/T480s/1_screws.jpg)

The back panel and the battery are removed. Important, ensure that all batteries, including the CMOS battery, are disconnected. Arrows indicate the direction you should pull the connectors. Pull the plastic part, not the wires, as the wires are thin and can be damaged.

![Battery]({{ site.baseurl }}/images/T480s/2_battery.jpg)

The top-right chip corresponds to the Thunderbolt SPI flash chip (1 MB). The chip located in the middle of the board corresponds to the BIOS (16 MB) chip, respectively. 

The chip located in the middle of the board contains the [Intel Management Engine (ME)](https://www.flashrom.org/ME) firmware.

![Chips]({{ site.baseurl }}/images/T480s/3_chips.jpg)

First [download]({{ site.baseurl }}/Downloading)  or build (please see [general building]({{ site.baseurl }}/general-building/) / [building x230]({{ site.baseurl }}/x230-maximized-building/)) the board rom for this board and verify its hash value.

Try to read the name of the SPI flash chip. The dot on the chip helps to identify the correct clip orientation. 

![SPI BIOS flash chip closed view]({{ site.baseurl }}/images/T480s/4_bios_chip_orientation.jpg)

## Flashing

First, connect the clip of your chosen SPI programmer (Raspberry Pi Pico was used in the sample commands) to the chip. Next, connect the programmer to the USB port of your other Linux-based computer with flashrom/flashprog installed. In my setup, the red wire should be where the dot is (the dot indicates pin 1). Here, please also see the flashing guide for the T430. 

Use `[flasher]` of your choice (flashrom or flashprog -- see [Tool Interchangeability]({{ site.baseurl }}/SPI-Programmer-Best-Practices/#tool-interchangeability)) with the programmer you selected ([programmer] -- see [Programmer Selection]({{ site.baseurl }}/SPI-Programmer-Best-Practices/#programmer-selection)):

```shell
sudo [flasher] --programmer [programmer]
```

Here is my output.

```
flashprog p1.3-2-geb2c041 on Linux 6.12.21-1.qubes.fc37.x86_64 (x86_64)
flashprog is free software, get the source code at https://flashprog.org

Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns).
serprog: Programmer name is "pico-serprog"
Found Winbond flash chip "W25Q128.V" (16384 kB, SPI) on serprog.
No operations were specified.
```

Create a backup and verify it (where the name of the flash chip is `YYY`):

```shell
sudo [flasher] --read ~/t480s_original_bios.bin --programmer [programmer] -c YYY
```

First output can be seen here. 

```
flashprog p1.3-2-geb2c041 on Linux 6.12.21-1.qubes.fc37.x86_64 (x86_64)
flashprog is free software, get the source code at https://flashprog.org

Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns).
serprog: Programmer name is "pico-serprog"
Found Winbond flash chip "W25Q128.V" (16384 kB, SPI) on serprog.
Reading flash... done.
```


```shell
sudo [flasher] --read ~/t480s_original_bios_1.bin --programmer [programmer] -c YYY
```
Second output can be seen here. 

```
flashprog p1.3-2-geb2c041 on Linux 6.12.21-1.qubes.fc37.x86_64 (x86_64)
flashprog is free software, get the source code at https://flashprog.org

Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns).
serprog: Programmer name is "pico-serprog"
Found Winbond flash chip "W25Q128.V" (16384 kB, SPI) on serprog.
Reading flash... done.
```

Make sure that the dump matches the chip content. If this is the case, the output of the following command will state `Verifying flash... VERIFIED`

```shell
sudo [flasher] --verify ~/t480_original_bios.bin --programmer [programmer] -c YYY
```
Make sure that files do not differ.

```shell
sha256sum t480s_original_bios.bin
sha256sum t480s_original_bios_1.bin
```

My dumps were the same. 

```
[user@flashing ~]$ sha256sum t480s_original_bios.bin 
54d58fdf217f41d4385576bb74f45f20de233d1a9d9ea2d6f1543b86111e1062  t480s_original_bios.bin
[user@flashing ~]$ sha256sum t480s_original_bios_1.bin 
54d58fdf217f41d4385576bb74f45f20de233d1a9d9ea2d6f1543b86111e1062  t480s_original_bios_1.bin
```

Alternative comparison is bit-by-bit. If the files are the same, there should be no output of this command. Otherwise, you will see a bit-by-bit difference between the files.

```shell
diff <(hexdump -C t480s_original_bios.bin) <(hexdump -C t480s_original_bios_1.bin)
```

If the files differ or the chip content does not match the dump, try reconnecting your programmer to the SPI flash chip and make sure your flashrom/flashprog software is up-to-date.


If they are the same, then write `t480s-hotp-maximized.rom` to the SPI flash chip:

```shell
sudo [flasher] --programmer [programmer] -c YYY -w ~/heads/build/x86/t480s-hotp-maximized/heads-t480s-hotp-maximized.rom
```

Here is a successful attempt. Be patient, it may take a while.

```
flashprog p1.3-2-geb2c041 on Linux 6.12.21-1.qubes.fc37.x86_64 (x86_64)
flashprog is free software, get the source code at https://flashprog.org

Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns).
serprog: Programmer name is "pico-serprog"
Found Winbond flash chip "W25Q128.V" (16384 kB, SPI) on serprog.
Reading old flash chip contents... done.
Erasing and writing flash chip... Erase/write done.
Verifying flash... VERIFIED.
```

If all goes, well you can connect the CMOS and internal battery, press the power button and you should see the keyboard LED flash. After that, Heads will boot into its GUI. 

Two reboots are sometimes needed after flashing. Force a power off by holding the power button for 10 seconds. Since the memory training data was wiped by the content of the fully flashed ROM, this is normal.

You should then follow through with [configuring keys]({{ site.baseurl }}/Configuring-Keys/).

## Flash Thunderbolt firmware
Important, ensure that power supply and all batteries, including the CMOS battery, are disconnected. After connecting the clip to the Thunderbolt chip as shown in the figure above read from the chip, making sure the connection is stable. The procedure is similar to the flashing Heads on the SPI chip. Therefore, comments are skipped.
(flashprog can also be used — substitute as in the main section above)

Check the chip you are connected to:
```shell
sudo [flasher] --programmer [programmer]
```
Output:
```
flashprog p1.3-2-geb2c041 on Linux 6.12.21-1.qubes.fc37.x86_64 (x86_64)
flashprog is free software, get the source code at https://flashprog.org

Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns).
serprog: Programmer name is "pico-serprog"
Found Winbond flash chip "W25Q80.V" (1024 kB, SPI) on serprog.
No operations were specified.
```

```shell
sudo [flasher] --programmer [programmer] --read ~/t480s_original_tb.bin --chip YYY
```

```shell
sudo [flasher] --programmer [programmer] --read ~/t480s_original_tb_1.bin --chip YYY
```

```shell
sudo [flasher] --programmer [programmer] --verify ~/t480s_original_tb.bin --chip YYY
```

```shell
sha256sum t480s_original_tb.bin
sha256sum t480s_original_tb_1.bin
```

```shell
diff <(hexdump -C t480_original_tb.bin) <(hexdump -C t480_original_tb_1.bin)
```

Flash the padded Thunderbolt firmware. The firmware file tb.bin is located in the blobs folder after you build the Heads locally, or in the CircleCI artifacts.

```shell
sudo [flasher] --programmer [programmer] --chip YYY --write ~/t480s_tb.bin
```
Done.
