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#![no_std]
use core::panic::PanicInfo;
use cortex_m;
use rp_hal::target_device as rp2040;
use bare_io::{Cursor, Write};
#[inline(never)]
#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
cortex_m::interrupt::disable();
let p = unsafe { rp2040::Peripherals::steal() };
p.XIP_CTRL
.ctrl
.write(|w| w.power_down().clear_bit().en().clear_bit());
let buf: &mut [u8] = unsafe { core::slice::from_raw_parts_mut(0x15000000 as *mut u8, 0x4000) };
let mut cur = Cursor::new(buf);
write!(&mut cur, "{}\n\0", info).ok();
if !(p.XOSC.status.read().stable().bit()) {
p.XOSC.startup.write(|w| unsafe {
w.delay().bits((12_000 + 128) / 256)
});
p.XOSC.ctrl.write(|w| {
w.freq_range()
.variant(rp2040::xosc::ctrl::FREQ_RANGE_A::_1_15MHZ)
.enable()
.variant(rp2040::xosc::ctrl::ENABLE_A::ENABLE)
});
while !(p.XOSC.status.read().stable().bit()) {}
}
reset_usb_boot(0, 0);
loop {}
}
unsafe fn rom_func_lookup(code: u32) -> u32 {
#[allow(non_camel_case_types)]
type rom_table_lookup_fn = extern "C" fn(*const u16, u32) -> u32;
let rom_table_lookup_ptr: *const u32 = rom_hword_as_ptr(0x18 as *const u16);
let rom_table_lookup: rom_table_lookup_fn = core::mem::transmute(rom_table_lookup_ptr);
let func_table = rom_hword_as_ptr(0x14 as *const u16) as *const u16;
rom_table_lookup(func_table, code)
}
fn rom_hword_as_ptr(rom_address: *const u16) -> *const u32 {
let ptr: u16 = unsafe { *rom_address };
ptr as *const u32
}
fn reset_usb_boot(usb_activity_gpio_pin_mask: u32, disable_interface_mask: u32) {
#[allow(non_camel_case_types)]
type reset_usb_boot_fn = extern "C" fn(u32, u32) -> !;
let ptr = unsafe { rom_func_lookup(rom_table_code(b'U', b'B')) };
if ptr as usize != 0 {
let func: reset_usb_boot_fn = unsafe { core::mem::transmute(ptr) };
func(usb_activity_gpio_pin_mask, disable_interface_mask);
}
}
fn rom_table_code(c1: u8, c2: u8) -> u32 {
c1 as u32 | ((c2 as u32) << 8)
}