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→Use case #2
In this case, the NOR flash is only used to store U-Boot and its environment. All the other images are stored onto the NAND flash. Specifically, the NAND flash has four partitions that are used to store respectively:
*The <code>uImage</code> binary image, which, in turn, consists of the Linux kernel and a [http://www.linuxfromscratch.org/blfs/view/svn/postlfs/initramfs.html <code>initramfs</code> image].
**By the way, this is the default format used for the root filesystem generated by [[/BELK-TN-006:_Using_PetaLinux_to_Build_BELK/BXELK_Software_Components|PetaLinux]]
**This partition is associated with the device file <code>/dev/mtd0</code>
*The PL bitstream
The resulting bootstrap sequence is like the following:
#U-Boot is retrieved from the NOR flash and copied into the SDRAM memory
#U-boot, in turn, reads from the NAND memory the <code>uImage</code>, the bitstream, the DTB, and copies them into the SDRAM memory#* As per PetaLinux's default configuration, the <code>uImage</code> image consists of the Linux kernel and the root filesystem image (<code>initramfs</code>)
#U-Boot starts the Linux kernel
#Finally, the Linux kernel mounts the root filesystem (<code>initramfs</code>) from the SDRAM memory and starts user-space applications and daemons.
It is worth remembering that <code>mtd0</code>,<code>mtd1</code>, and <code>mtd2</code> are used as raw partitions while <code>mtd3</code> is associated with a block device in order to mount a filesystem.
