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Zynq BootROM Secrets: UART loader

Recently I acquired (md5: ADF639AFE9855EE86C8FAAD216C970D9) the Zynq bootrom, and during the reversing process uncovered some interesting secrets, one of which is an as-of-yet undocumented UART loader. As documented the Zynq bootrom will load from NOR/NAND/SPI flashes, eMMC/SDIO-based storage (unfortunately) not USB, or anything else more complex.

Not sure why Xilinx didn't document this. In my brief testing it is super unreliable if you just spit everything at once - they reset the RX/TX paths during the process, so timing is critical, but that might be the janky meter-long ftdi cable. You can change the baudrate during the process, but I was too lazy to do the math.

Here's the disassembly that made me look twice (that, and checks for the MIO boot_mode[2:0] that weren't specified in the docs :)):

ROM:0000A220 BL              uart_init

Zynq BootROM Secrets: Exposing the bootROM with the UART loader

Last time I wrote about this, I lied a little - There is an interesting bug in the UART loader, and it may have been exactly why Xilinx didn't document it. In short: The UART loader writes the entire UART payload to a location in memory (nominally 0x4_0000). The ROM is architected such that when the boot mode is selected, it registers a callback that is called when the ROM wants more data from the boot device. For the UART loader, this is pretty simple - here's the whole thing:

; void uart_callback(u32 r0_offset, void* r1_dest, i32 r2_nbytes)
ROM:0000A578 PUSH            {R3,LR}
ROM:0000A57C MOV             R3, #uart_buff
ROM:0000A584 MOV             R12, #1
ROM:0000A588 LDR             R3, [R3]

How to build SQLite3 .lib file on Windows 10

Download source from source

For example: source https://www.sqlite.org/2023/sqlite-amalgamation-3430100.zip
Download binary from binary

For example: binary https://www.sqlite.org/2023/sqlite-dll-win64-x64-3430100.zip
Extract both archives to the same directory

Need to do this in both php.ini files !!!

Attention Wamp/Wordpress/windows users. I had this issue for hours and not even the correct answer was doing it for me, because I was editing the wrong php.ini file because the question was answered to XAMPP and not for WAMP users, even though the question was for WAMP.

here's what I did

Download the certificate bundle.

Put it inside of C:\wamp64\bin\php\your php version\extras\ssl

Async Await Best Practices Cheat Sheet

Summary of Asynchronous Programming Guidelines

Name	Description	Exceptions
Avoid async void	Prefer async Task methods over async void methods	Event handlers
Async all the way	Don't mix blocking and async code	Console main method
Configure context	Use `ConfigureAwait(false)` when you can	Methods that require context

Google Script CRUD

By Ryan Aunur Rassyid

Simply create RESTful API with Google Script and store it to Google SpreadSheet like a Pro.

	[Unit]
	Wants=network-pre.target
	Before=network-pre.target shutdown.target

	[Service]
	User=root
	ExecStart=/bin/sh -ec '\
	[ -x /usr/bin/wslinfo ] && [ "$(/usr/bin/wslinfo --networking-mode)" = "mirrored" ] \|\| exit 0;\
	echo "\
	add chain ip nat WSLPREROUTING { type nat hook prerouting priority dstnat - 1; policy accept; };\

	import numpy as np
	def calculate_psnr(img1, img2, max_value=255):
	""""Calculating peak signal-to-noise ratio (PSNR) between two images."""
	mse = np.mean((np.array(img1, dtype=np.float32) - np.array(img2, dtype=np.float32)) ** 2)
	if mse == 0:
	return 100
	return 20 * np.log10(max_value / (np.sqrt(mse)))

	# Location: /etc/nginx/sites-available/domain.tld.conf
	server {
	listen 80;

	# listen 443 ssl;
	# include snippets/snakeoil.conf;

	root /var/www/domain.tld/public;

	index index.html index.php;