Partition Configuration#

NVIDIA® Jetson™ Linux supports formatting mass storage media into multiple partitions for storing data, such as the device OS image, bootloader image, device firmware, and bootloader splash screen.

How Jetson Partition Configurations Are Described#

Some Jetson platforms have similar characteristics, such as identical partition configurations. This topic groups these platforms and provides information about each group. The supported platforms are grouped in the following way:

Group

Includes platforms

NVIDIA® Jetson AGX Orin™ series
Jetson AGX Orin 32GB (P3701-0000, for development only)
Jetson AGX Orin 32GB (P3701-0004)
Jetson AGX Orin 64GB (P3701-0005)
Jetson AGX Orin Industrial (P3701-0008)

NVIDIA® Jetson Orin™ NX series
Jetson Orin NX 16GB (P3767-0000)
Jetson Orin NX 16GB (P3767-0001)

NVIDIA® Jetson Orin™ Nano series
Jetson Orin Nano 8GB (P3767-0003)
Jetson Orin Nano 4GB (P3767-0004)
Jetson Orin Nano 8GB (P3767-0005, for development only)

NVIDIA® Jetson Thor series
Jetson T5000 (P3834-0008)

Partition Configuration Files#

A partition configuration file describes the mass storage devices and partitions on a platform.

The following table describes the definitions of all of the partition configurations supported by Jetson Linux. The File column specifies the filename of the partition configuration file the defines the configuration, and the Device columns specify the <device> block in that file that defines the configuration (refer to <device> Element Tag Attributes for more information).

Platform & Configuration

Boot Partition Device

User Partition Device

File

Jetson AGX Orin Developer Kit

QSPI_NOR

sdmmc_user on 32GB eMMC

flash_t234_qspi_sdmmc.xml

Jetson Orin Nano Developer Kit

QSPI-NOR

SD card/USB/NVMe drive

flash_t234_qspi_sd.xml
Commercial Modules:

  • Jetson AGX Orin 32GB (P3701-0004)

  • Jetson AGX Orin 64GB (P3701-0005)

  • Jetson AGX Orin Industrial (P3701-0008)

QSPI_NOR

sdmmc_user on eMMC

flash_t234_qspi_sdmmc.xml
Commercial Modules:

  • Jetson Orin 16GB (P3767-0000)

  • Jetson Orin 8GB (P3767-0001)

  • Jetson Orin 8GB (P3767-0003)

  • Jetson Orin 4GB (P3767-0004)

QSPI_NOR

USB/NVMe drive

flash_t234_qspi_sd.xml

Jetson AGX Thor Developer Kit

QSPI_NOR

NVMe SSD

flash_l4t_t264_nvme.xml flash_l4t_t264_qspi.xml

Each file’s name typically incorporates its processor name (t234 or t264), the type of memory the partitions are flashed to (nvme for NVMe SSD, sd for SD Card, spi for SPI, or emmc for eMMC), and in some cases, the module’s part number, for example, p3668).

During the flashing procedure, l4t_initrd_flash.sh does the following:

  1. Reads the partition configuration file <device>.xml.

  2. Translates keywords into values specified in <device>.conf or in command-line options.

  3. Saves the translated data in bootloader/flash.xml.

l4t_initrd_flash reads in bootloader/flash.xml and flashes the device that is specified by bootloader/flash.xml.

Refer to List of Translated Keywords for more information.

Format of a Partition Configuration File#

Each partition configuration file defines one or more partition layouts for a specific configuration of a specific Jetson device. The file is composed of the following XML elements:

  • A standard XML prolog.

  • One or more <partition_layout> elements, each of which defines one partition layout.

  • In each <partition_layout> element, a <device> element for each device, for example, each type of flashed memory, that the layout uses.

  • In each <device> element, a <partition> element for each partition in that device’s partition layout.

  • In each <partition> element, a group of other elements that specify various properties of the partition.

<partition_layout> Element#

The <partition_layout> element has the following syntax:

<partition_layout version="01.00.0000">
    <!-- Device elements go here. -->
</partition>

<device> Element#

The partition configuration file contains a device element for each subdevice; for example, for the eMMC boot and user hardware partitions. This element must be present even if the devices are not divided into subdevices.

The <device> element has the following syntax:

<device type="<device type>" instance="<instance>">
    <!-- Partition elements go here. -->
</device>

<device> Element Tag Attributes#

The following table describes the <device> tag’s attributes and their legal values.

Device attributes

Values

Description

device type

sdmmc_boot; sdmmc_user SPI; external

Required. Specifies the type of device. eMMC boot0 and boot1 hardware partitions are treated as a single sdmmc_boot entry.

instance

0-3

Required. Specifies the device instance: 0 for SPI or NVMe, or 3 (typically) for eMMC.

<partition> Element#

Each <partition> element has the following syntax:

<partition name="<name>" type="<type>" oem_sign="true ">
    <!-- partition properties go here -->
</partition>

<partition> Element Tag Attributes#

This table describes the attributes supported for partition elements and their legal values.

Device attributes

Values

name

See the files listed in the table of partition configuration files.

Required. Specifies a name for the partition. The name can have a maximum of 36 characters. There are three kinds of partitions: mandatory, optional, and user-defined. All mandatory and optional partition names must be associated with the specific partition type. All user-defined partition names must be associated with partition type data.

type

See the files listed in the table of partition configuration files.

Required. Specifies the type of partition. Certain partition types are valid only when they are associated with specific partition names.

oem_sign

True, False, or unspecified.

If True, append a generic signature header to the binary and perform OEM signing on it. If False, append a NULL signature header to the binary and perform NULL signing on it.

<partition> Child Elements#

The following tags specify the properties of a <partition> element:

Tag

Values

Description

<allocation_policy>

sequential

Specifies the type of allocation policy. Sequential partitions begin immediately after the preceding partition.

<filesystem_type>

basic

The filesystem_type value basic specifies a “raw” partition. (The legacy “ext2” file system has been deprecated.)

<size>

<partition_size>

Required. Specifies the size of the partition in bytes. May be a decimal number or a hexadecimal number of up to 16 digits.

The partition size may be equal to or greater than the size of the file to be written to the partition. Specifying a greater size allows you to increase the file size later without changing the partition configuration file.

If the partition size is less than an erase block size, it aligns itself to the partition erase block boundary.

The size property of the secondary GPT partition, which is defined at the end of each device, must always be 0xffffffffffffffff. TegraFlash calculates this partition’s size automatically; the preceding partition is extended to fill any free space before the secondary GPT.

<file_system_attribute>

0

Not implemented.

<allocation_attribute>

0x008 or 0x808

Must be 0x808 for the partition immediately preceding the secondary GPT.

<percent_reserved>

0

Reserved for future use.

<filename>

<filename> or empty

Specifies the name of the file to write into the partition. If the filename is empty, no data is written to the partition.

List of Translated Keywords#

The following table provides keywords that you can use as the text for some <partition> child elements. When the partition configuration file processor encounters one of these keywords, it substitutes the value shown or described in the table.

Keyword

Default translated value in flash.xml

MB1FILE

mb1_t246_prod.bin

SPEFILE

spe_t234.bin

APPSIZE

30064771072

APPFILE

system.img

MTS_MCE

mce_flash_o10_cr_prod.bin

TBCFILE

uefi_jetson.bin

TBCDTB-FILE

Appropriate bootloader DTB file name

TOSFILE

tos-optee_t234.img

EKSFILE

eks.img

BPFFILE

bpmp_t264-TA1090SA-A1_prod.bin

BPFDTB-FILE

Appropriate BPMP DTB file name

CAMERAFW

camera-rtcpu-t264-rce.bin

LNXSIZE

67108864

LNXFILE

boot.img

DTB_FILE

Appropriate kernel DTB file name

RECFILE

Name of appropriate recovery kernel image

RECDTB-FILE

Name of appropriate recovery kernel dtb file

External Storage Device Partition#

To create a partition configuration file for flashing to an external storage device, start with a default SD card partition table as a template (for example, the Jetson AGX Orin development module sdmmc_user partition from the table of partition configuration files). Change the device type to external and the instance number to zero, as in the following example. An external partition configuration file must contain at least three partitions: master_boot_record, primary_gpt, and secondary_gpt.

For both SCSI devices (such as SCSI flash drives and hard disk drives) and NVMe devices (such as NVMe SSDs), the device type is external. You must also update num_sectors to correctly specify the total amount of storage available on your external device. For example, if an NVMe device has 1024209543168 bytes available, you must change num_sectors to 1024209543168 / 512 = 2000409264 sectors.

<partition_layout version="01.00.0000">
  <device type="nvme" instance="0" sector_size="512" num_sectors="61071360">
    <partition name="master_boot_record" type="protective_master_boot_record">
      <allocation_policy> sequential </allocation_policy>
      <filesystem_type> basic </filesystem_type>
      <size> 512 </size>
      <file_system_attribute> 0 </file_system_attribute>
      <allocation_attribute> 8 </allocation_attribute>
      <percent_reserved> 0 </percent_reserved>
      <description> **Required.** Contains protective MBR. </description>
    </partition>
    <partition name="primary_gpt" type="primary_gpt">
      <allocation_policy> sequential </allocation_policy>
      <filesystem_type> basic </filesystem_type>
      <size> PPTSIZE </size>
      <file_system_attribute> 0 </file_system_attribute>
      <allocation_attribute> 8 </allocation_attribute>
      <percent_reserved> 0 </percent_reserved>
      <description> **Required.** Contains primary GPT of the `sdmmc_user` device. All
        partitions defined after this entry are configured in the kernel, and are
        accessible by standard partition tools such as gdisk and parted. </description>
    </partition>
    <partition name="secondary_gpt" type="secondary_gpt">
      <allocation_policy> sequential </allocation_policy>
      <filesystem_type> basic </filesystem_type>
      <size> 0xFFFFFFFFFFFFFFFF </size>
      <file_system_attribute> 0 </file_system_attribute>
      <allocation_attribute> 8 </allocation_attribute>
      <percent_reserved> 0 </percent_reserved>
      <description> **Required.** Contains secondary GPT of the `sdmmc_user`
        device. </description>
    </partition>
  </device>
</partition_layout>