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<section begin=BTELK/>= Introduction = Standalone boot==
This document shows some examples related to configuring Bora/BoraX/BoraLite for standalone operativity.
{{ImportantMessage|text=It is worth remembering that the examples shown in this article don't make use of any image script. This technique is used by the bootable microSD card delivered along with the kit, instead. For more details, please refer to [[Working_with_the_Yocto_build_system#bootscript|this section]].}}
===Use case #1=======Introduction====
This configuration makes use of one of the most common partitioning schemes, that is:
*The NOR flash acts as boot memory; as such, it contains
*Once started, the Linux kernel mount the root filesystem from a NAND partition.
=====Testbed=====
This configuration was tested with the following testbed:
*SOM: DBXF4110D2R
*software: [[BELK/BXELK_software_components#BELK_3.0.1_.2F_BXELK_1.0.0|BXELK 1.0.0]]
==== Program the root filesystem in NAND flash ====
This is a common step for both booting options.
You can now safely reboot or turn off the system.
==== Program the boot images in NOR flash====
It is assumed that the following U-Boot's environment variables are defined:
</pre>
===Use case #2=======Introduction====
This configuration makes use the most common partitioning schemes for booting completely from NAND flash, that is:
*The NAND flash acts as boot memory and root file system storage; as such, it contains
*The Linux kernel mount the root filesystem from a NAND partition.
=====Testbed=====
This configuration was tested with the following testbed:
*SOM: DBTD4111I0R
*software: [[BELK/BXELK_software_components#BELK_4.1.0|BELK 4.1.0]]
==== Program the root filesystem in NAND flash ====
This step can be followed in the same way as described [[Standalone_boot_(BELK/BXELK)#Program_the_root_filesystem_in_NAND_flash | before]]
==== Program the boot images in NAND flashfrom U-Boot ====
It is assumed that the following U-Boot's environment variables are defined:
</pre>
==== Program the boot images in NAND flash from Linux ==== * Get kernel and device tree images with the following <code>tftp</code> commands E.g.: <pre class="board-terminal">root@bora:~# tftp -g -r bora/linux/belk-4.1.0_uImage 192.168.0.23root@bora:~# tftp -g -r bora/linux/belk-4.1.0_bora.dtb 192.168.0.23root@bora:~# tftp -g -r bora/belk-4.1.0_bora_BASE_fpga.bin 192.168.0.23root@bora:~# ls -laroot@bora:~# ls -ladrwxr-xr-x 2 root root 4096 Mar 5 2021 .drwxrwxrwx 6 root root 4096 Mar 5 2021 ..-rw-r--r-- 1 root root 10073 Mar 5 2021 belk-4.1.0_bora.dtb-rw-r--r-- 1 root root 4045564 Mar 5 2021 belk-4.1.0_bora_BASE_fpga.bin-rw-r--r-- 1 root root 3796168 Mar 5 2021 belk-4.1.0_uImageroot@bora:~#</pre>* now the binary images have been retrieved form the ''tftp'' server (like the U-Boot tftp download)* check the mtd partitioning for identifying the proper <code>/dev/mtdX</code> device<pre class="board-terminal">root@bora:~# cat /proc/mtddev: size erasesize namemtd0: 00040000 00020000 "nand-SPL"mtd1: 000c0000 00020000 "nand-uboot"mtd2: 00040000 00020000 "nand-uboot-env1"mtd3: 00040000 00020000 "nand-uboot-env2"mtd4: 00600000 00020000 "nand-bitstream"mtd5: 00080000 00020000 "nand-device-tree"mtd6: 00800000 00020000 "nand-linux"mtd7: 1f000000 00020000 "nand-rootfs"root@bora:~#</pre>It is possible to see the mtd partition for the NAND flash: i.e. <code>mtd4</code> for the fpga bitstream, <code>mtd5</code> for the device tree and <code>mtd6</code> for the kernel * using the mtd partitioning, program the binary images in the proper <code>/dev/mtdX</code> device* the <code>mtd-utils</code> commands <code>flash_erase</code> and <code>nandwrite</code> can be used for this purposes: see [https://bootlin.com/blog/managing-flash-storage-with-linux here] for more information<pre>root@bora:~# flash_erase --helpUsage: flash_erase [options] MTD_DEVICE <start offset> <block count>Erase blocks of the specified MTD device.Specify a count of 0 to erase to end of device. -j, --jffs2 format the device for jffs2 -N, --noskipbad don't skip bad blocks -u, --unlock unlock sectors before erasing -q, --quiet do not display progress messages --silent same as --quiet --help display this help and exit --version output version information and exitroot@bora:~# nandwrite --helpUsage: nandwrite [OPTION] MTD_DEVICE [INPUTFILE|-]Writes to the specified MTD device. -a, --autoplace Use auto OOB layout -m, --markbad Mark blocks bad if write fails -n, --noecc Write without ecc -N, --noskipbad Write without bad block skipping -o, --oob Input contains oob data -O, --onlyoob Input contains oob data and only write the oob part -s addr, --start=addr Set output start address (default is 0) -p, --pad Pad writes to page size -b, --blockalign=1|2|4 Set multiple of eraseblocks to align to --input-skip=length Skip |length| bytes of the input file --input-size=length Only read |length| bytes of the input file -q, --quiet Don't display progress messages -h, --help Display this help and exit --version Output version information and exitroot@bora:~#</pre>* program the binary images in each mtd device<pre class="board-terminal">root@bora:~# flash_erase /dev/mtd4 0 0Erasing 128 Kibyte @ 5e0000 -- 100 % completeroot@bora:~# nandwrite -p /dev/mtd4 belk-4.1.0_bora_BASE_fpga.binWriting data to block 0 at offset 0x0Writing data to block 1 at offset 0x20000Writing data to block 2 at offset 0x40000Writing data to block 3 at offset 0x60000Writing data to block 4 at offset 0x80000Writing data to block 5 at offset 0xa0000Writing data to block 6 at offset 0xc0000Writing data to block 7 at offset 0xe0000Writing data to block 8 at offset 0x100000Writing data to block 9 at offset 0x120000Writing data to block 10 at offset 0x140000Writing data to block 11 at offset 0x160000Writing data to block 12 at offset 0x180000Writing data to block 13 at offset 0x1a0000Writing data to block 14 at offset 0x1c0000Writing data to block 15 at offset 0x1e0000Writing data to block 16 at offset 0x200000Writing data to block 17 at offset 0x220000Writing data to block 18 at offset 0x240000Writing data to block 19 at offset 0x260000Writing data to block 20 at offset 0x280000Writing data to block 21 at offset 0x2a0000Writing data to block 22 at offset 0x2c0000Writing data to block 23 at offset 0x2e0000Writing data to block 24 at offset 0x300000Writing data to block 25 at offset 0x320000Writing data to block 26 at offset 0x340000Writing data to block 27 at offset 0x360000Writing data to block 28 at offset 0x380000Writing data to block 29 at offset 0x3a0000Writing data to block 30 at offset 0x3c0000root@bora:~# flash_erase /dev/mtd5 0 0Erasing 128 Kibyte @ 60000 -- 100 % completeroot@bora:~# nandwrite -p /dev/mtd5 belk-4.1.0_bora.dtbWriting data to block 0 at offset 0x0root@bora:~# flash_erase /dev/mtd6 0 0Erasing 128 Kibyte @ 7e0000 -- 100 % completeroot@bora:~# nandwrite -p /dev/mtd6 belk-4.1.0_uImageWriting data to block 0 at offset 0x0Writing data to block 1 at offset 0x20000Writing data to block 2 at offset 0x40000Writing data to block 3 at offset 0x60000Writing data to block 4 at offset 0x80000Writing data to block 5 at offset 0xa0000Writing data to block 6 at offset 0xc0000Writing data to block 7 at offset 0xe0000Writing data to block 8 at offset 0x100000Writing data to block 9 at offset 0x120000Writing data to block 10 at offset 0x140000Writing data to block 11 at offset 0x160000Writing data to block 12 at offset 0x180000Writing data to block 13 at offset 0x1a0000Writing data to block 14 at offset 0x1c0000Writing data to block 15 at offset 0x1e0000Writing data to block 16 at offset 0x200000Writing data to block 17 at offset 0x220000Writing data to block 18 at offset 0x240000Writing data to block 19 at offset 0x260000Writing data to block 20 at offset 0x280000Writing data to block 21 at offset 0x2a0000Writing data to block 22 at offset 0x2c0000Writing data to block 23 at offset 0x2e0000Writing data to block 24 at offset 0x300000Writing data to block 25 at offset 0x320000Writing data to block 26 at offset 0x340000Writing data to block 27 at offset 0x360000Writing data to block 28 at offset 0x380000root@bora:~#</pre>* once rebooted, configure U-Boot to apply the new configuration in NAND<pre class="board-terminal">......Hit ENTER within 3 seconds to stop autobootBora> setenv bootcmd 'run nand_nand'Bora> saveenvSaving Environment to SPI Flash...SF: Detected s25fl256s_64k with page size 256 Bytes, erase size 64 KiB, total 64 MiBErasing SPI flash...Writing to SPI flash...doneValid environment: 1Bora> </pre> * the system is then ready to boot retrieving the storage binary images from NAND<pre class="board-terminal">Bora> bootNAND read: device 0 offset 0x180000, size 0x600000 6291456 bytes read: OK NAND read: device 0 offset 0x800000, size 0x800000 8388608 bytes read: OK NAND read: device 0 offset 0x780000, size 0x80000 524288 bytes read: OK## Booting kernel from Legacy Image at 02080000 ... Image Name: Linux-4.9.0-belk-4.1.0-xilinx Image Type: ARM Linux Kernel Image (uncompressed) Data Size: 3796104 Bytes = 3.6 MiB Load Address: 00008000 Entry Point: 00008000 Verifying Checksum ... OK## Flattened Device Tree blob at 02000000 Booting using the fdt blob at 0x2000000 Loading Kernel Image ... OK Loading Device Tree to 1effa000, end 1efff758 ... OKSwitching to NAND storage before starting Linux Starting kernel ... Uncompressing Linux... done, booting the kernel.[ 0.000000] Booting Linux on physical CPU 0x0[ 0.000000] Linux version 4.9.0-belk-4.1.0-xilinx (jenkins@linuxserver2) (gcc version 6.2.1 20161016 (Linaro GCC 6.2-2016.11) ) #1 SMP PREEMPT Tue Dec 24 11:34:28 CET 2019[ 0.000000] CPU: ARMv7 Processor [413fc090] revision 0 (ARMv7), cr=18c5387d[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache[ 0.000000] OF: fdt:Machine model: Bora[ 0.000000] bootconsole [earlycon0] enabled[ 0.000000] cma: Reserved 16 MiB at 0x3f000000[ 0.000000] Memory policy: Data cache writealloc[ 0.000000] On node 0 totalpages: 262144[ 0.000000] free_area_init_node: node 0, pgdat c0a2ddc0, node_mem_map ef7f7000[ 0.000000] Normal zone: 1536 pages used for memmap[ 0.000000] Normal zone: 0 pages reserved[ 0.000000] Normal zone: 196608 pages, LIFO batch:31......</pre> ====Full bootstrap procedure====
For the reader's convenience, the following box shows the full bootstrap procedure (please, click on the "Expand" link):
</pre>
===Use case #3=======Introduction====
This example makes use of the partitioning scheme illustrated in the following images.
To setup the desired standalone configuration, several operations need to be carried out. They are detailed in the following sections. It is assumed that the SOM can boot from the NOR flash. If not, please see [[Restoring_U-Boot_on_SPI_NOR_flash_(BELK/BXELK)|this page]].
=====Testbed=====
The testbed used to test this configuration consists of the following boards:
*SOM: DBXD4110S2R
*Software: BXELK 4.0.0 + PetaLinux 2017.1
====Storing the images onto the raw partitions of the NAND memory====
Before storing the images into the NAND flash, the bitstream must be converted. For more details, please refer to [[BELK-AN-008: Programming the FPGA Bitstream with U-Boot|this page]]:
<pre class="board-terminal">
Please note that the variable <code>bootcmd</code> is set to run the desired boot sequence (<code>nandboot2</code>).
====Formatting the fourth partition of the NAND memory (<code>mtd3</code>)====
After setting up the U-Boot environment, it is possible to start a full bootstrap sequence by issuing the <code>boot</code> command. Please refer to [[#Full bootstrap procedure|this section]] to see the dump of the serial console during the full bootstrap sequence.
</pre>
====Full bootstrap procedure====
For the reader's convenience, the following box shows the full bootstrap procedure (please, click on the "Expand" link):
</pre>
====Additional notes====
*<code>mtd0</code>, <code>mtd1</code>, and <code>mtd2</code> are significantly larger than the files they store used in this example. This allows having a spare room to store larger images. For the sake of simplicity, U-Boot was configured to read the whole partitions (see how the <code>loadunand</code>, <code>loadfdtnand</code>, and <code>loadfpga2</code> variables are defined). Obviously, this affect the overall boot time negatively. To optimize it, these variables have to be changed in order to read just the required amount of data according to the size of the actual stored files.
*As stated previously, the root filesystem is <code>initramfs</code> and thus not persistent. Consequently, every time the system boots, the directory <code>/mnt/data3</code> must be created before mounting the ''UBIFS'' file system stored in the NAND flash.
<section end=BTELK/>
