View source for System boot and recovery via microSD card (BELK/BXELK)

{{InfoBoxTop}}
{{Applies To Bora}}
{{Applies To BoraX}}
{{Applies To BoraLite}}
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== History ==
{| class="wikitable" border="1"
!Version
!Date
!BELK version
!Notes
|-
|1.0.0
|November 2015
|[[Bora_Embedded_Linux_Kit_(BELK)#BELK_software_components|3.0.0]]
|First release
|-
|2.0.0
|December 2016
|BELK 3.0.1 / BXELK 1.0.0
|Added information about new kits
|-
|3.0.0
|July 2017
|BELK 4.0.0 / BXELK 2.0.0
|Added information about new kits
|-
|}

<section begin=BELK/>
==System boot and recovery via microSD card==
BELK provides a bootable microSD that can be used not only to quickly start the system, but also as a recovery method in case the primary boot device (eg. QSPI NOR flash) gets erased or corrupted. The following sections describe how to create a bootable SD card and how to configure the system for booting from SD. [[BORA_SOM/BELK-L/Deployment/Restoring_U-Boot_on_NOR_flash|This article]], for example, shows how to make use of such a card to restore the U-Boot image onto the NOR flash.

{{ImportantMessage|text=It is worth remembering that the bootable microSD card described in this article is not configured to perform a full boot sequence, including the operating system bootstrap. The bootable microSD card delivered along with the kit is set up to do a full bootstrap sequence, instead. For more details, please refer to [[Working_with_the_Yocto_build_system#bootscript|this section]].}}

===How to create a bootable microSD card===
====BELK <= 3.0.2 / BXELK <= 1.0.1====
This section describes how to create a new bootable microSD card from scratch for '''BELK <= 3.0.2''' and '''BXELK <= 1.0.1'''.
The following components must be available:
*FSBL built with Vivado 2014.4 as described [[BORA_SOM/BELK-L/Development/Creating_and_building_a_Vivado_example|here]]
*U-boot built in elf format, as described in [[BORA_SOM/BELK-L/Development/Building_U-Boot|here]]
*FPGA bitstream (optional).
The procedure is the following:
*from the Vivado 2014.4 SDK, apply the required patches to the <code>main.c</code> project file.This step can be done in two ways:
**manually, directly modifying the <code>main.c</code> file adding the following code snippets:
<pre>
----CUT----
	/*
	 * Unlock SLCR for SLCR register write
	 */
	SlcrUnlock();

+	*((u32 *)0xF8000830) = 0x003F003F;
+	*((u32 *)0xF8000834) = 0x003F003F;

	/* If Performance measurement is required 
	 * then read the Global Timer value , Please note that the
----CUT----

----CUT----
	/*
	 * Read bootmode register
	 */
	BootModeRegister = Xil_In32(BOOT_MODE_REG);
	BootModeRegister &= BOOT_MODES_MASK;

+	// always init QSPI
+	InitQspi();
	
	/*
	 * QSPI BOOT MODE
	 */
#ifdef XPAR_PS7_QSPI_LINEAR_0_S_AXI_BASEADDR
----CUT----
</pre>
**automatically, using the ''Apply Patch'' function and selecting the <code>belk-sd-boot.patch</code> file provided with the BELK (please refer to the following images):
[[File:Patch sd 1.png|thumb|center|600px|Automatic patch applying (1/3)]]
[[File:Patch sd 2.png|thumb|center|600px|Automatic patch applying (2/3)]]
[[File:Patch sd 3.png|thumb|center|600px|Automatic patch applying (3/3)]]
*once the patch is applied, rebuild the FSBL project
*from the Xilinx Tools menu, select ''Create Zynq Boot Image''
*select Create New BIF file and insert path and name of the .bif file
*in the ''Boot image partitions'' section, click on ''Add'' to browse and add the following files:
**FSBL in .elf format, with ''bootloader'' as partition type 
**(optional) FPGA bitstream in .bit format, with partition type ''datafile''
**U-boot binary with .elf extension, with partition type ''datafile''
*in the ''Output path'' section, browse and select the path where saving the <code>boot.bin</code> file
*on a PC, format the microSD card creating a FAT32 partition
*copy the <code>boot.bin</code> file to the microSD card FAT32 partition.

====BELK-4.0.0 / BXELK-2.0.0====
This section describes how to create a new bootable microSD card from scratch for '''BELK-4.0.0''' and '''BXELK-2.0.0'''.
The following components must be available:
*U-boot SPL and U-boot second stage built as described in [[BORA_SOM/BELK-L/Development/Building_U-Boot|here]]
*FPGA bitstream (optional).
The procedure is the following:
*on a PC, format the microSD card creating a FAT32 partition
*copy the following files to the microSD card FAT32 partition:
** U-boot SPL: <code>boot.bin</code>
** U-boot second stage: <code>u-boot.img</code>
** Fpga bitstream .bit (optional): <code>fpga.bit</code>

===How to configure the system for microSD boot===
For BORA / BORA Evaluation kit systems please refer to [[BORA_SOM/BORA_Evaluation_Kit/Getting_started/Boot_Configurations|this link]].

For BORA Xpress/ BORA xpress Evaluation kit systems please refer to [[BORA_Xpress_SOM/BORA_Xpress_Evaluation_Kit/Getting_started/Boot_Configurations|this link]].

For BORA Lite Evaluation kit systems please refer to [[BORA_Lite_SOM/BORA_Lite_Evaluation_Kit/Getting_started/Boot_Configurations|this link]].

{{ImportantMessage|text=In case the microSD card provided along with the kit is used, the Programmable Logic is automatically programmed with the [[BORA_SOM/BELK-L/Development/Creating_and_building_a_Vivado_example|example design]] during the boot process.
}}
<section end=BELK/>