FreeRTOS on Zynq-7000 SD Card Boot Issue

Kernel
1

Hello Everyone,

I’m trying to get FreeRTOS up and running on a Zynq-7000 board. I’ve created a standalone FSBL (zsys_wrapper) and a bare-metal project. Added all of the FreeRTOS source and the Zynq specific portable stuff.

Run the project in debug mode over JTAG - works great. Everything comes up and works perfectly.

Create an SD Card BOOT.BIN, and things go sideways. I enabled FSBL debugging, and the output is as follows:

Xilinx First Stage Boot Loader 

Release 2024.2	Aug  5 2026-21:59:17
Devcfg driver initialized 
Silicon Version 3.1
Watchdog driver initialized 
Boot mode is SD
SD: rc= 0

SD Init Done 
Flash Base Address: 0xE0100000
Reboot status register: 0x60410000
Multiboot Register: 0x0000C000
Image Start Address: 0x00000000
Partition Header Offset:0x00000C80
Partition Count: 511942921814016
Partition Number: 4295037348
Header Dump
Image Word Len: 0x00093B00
Data Word Len: 0x00093B00
Partition Word Len:0x00093B00
Load Addr: 0x00000000
Exec Addr: 0x00000000
Partition Start: 0x000075D0
Partition Attr: 0x00000020
Partition Checksum Offset: 0x00000000
Section Count: 0x00000001
Checksum: 0xFFE3D6BE
Bitstream
In FsblHookBeforeBitstreamDload function 
In FsblHookAfterBitstreamDload function 
Partition Number: 8589934595
Header Dump
Image Word Len: 0x0001A8A8
Data Word Len: 0x0001A8A8
Partition Word Len:0x0001A8A8
Load Addr: 0x00100000
Exec Addr: 0x001000A8
Partition Start: 0x0009B0D0
Partition Attr: 0x00000010
Partition Checksum Offset: 0x00000000
Section Count: 0x00000002
Checksum: 0xFFD1521D
Application
Partition Number: 12884901892
Header Dump
Image Word Len: 0x00001004
Data Word Len: 0x00001004
Partition Word Len:0x00001004
Load Addr: 0x0016C000
Exec Addr: 0x00000000
Partition Start: 0x000B5980
Partition Attr: 0x00000010
Partition Checksum Offset: 0x00000000
Section Count: 0x00000000
Checksum: 0xFFDDB403
Application
Handoff Address: 0x001000A8
IRQ_HANDLER 
FSBL Status = 0x6802E000002C

This Boot Mode Doesn't Support Fallback
In FsblHookFallback function

Anyone ever seen anything like this before? I’ve been sweating over this for two days now, and I’ve made roughly zero progress. Using Vivado and VitisClassic 2024.2

Should mention, I’ve gotten FreeRTOS running on Zynq many times before. Wanted to update to newer Vivado/Vitis and start with a fresh project. First time I’ve come across this issue.

Appreciate any guidance!

2

Interesting. Found something.

Removing the Core0_nIRQ Interrupt from the PS7 Block design fixes the problem. Issue: I need the Core0_nIRQ Interrupt. The “IRQ_HANDLER” gave me that idea.

image
image1552×1074 28.8 KB

Anyone seen this before?

3

More information. Adding the following code to the FSBL right before FsblHandoff(HandoffAddress) ?fixes? the problem. I’m just not feeling super awesome about hand modifying the FSBL. Thoughts?

	//Disable nIRQ Interrupt
	XScuGic InterruptController;
	int IntStatus;
	XScuGic_Config *GicConfig;
	GicConfig = XScuGic_LookupConfig(XPAR_SCUGIC_SINGLE_DEVICE_ID);
	if (NULL == GicConfig) {
		return XST_FAILURE;
	}

	// 2. Initialize the GIC driver
	IntStatus = XScuGic_CfgInitialize(&InterruptController, GicConfig, GicConfig->CpuBaseAddress);
	if (IntStatus != XST_SUCCESS) {
		return XST_FAILURE;
	}

	XScuGic_Disable(&InterruptController, XPS_IRQ_INT_ID);