You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: spi.rs
    path of file: ./repos/embassy/examples/stm32h7/src/bin
    
    the code of the file until where you have to start completion: #![no_std]
#![no_main]

use core::fmt::Write;
use core::str::from_utf8;

use cortex_m_rt::entry;
use defmt::*;
use embassy_executor::Executor;
use embassy_stm32::dma::NoDma;
use embassy_stm32::peripherals::SP
    
fn main() -> ! {
    info!("Hello World!");

    let mut config = Config::default();
    {
        use embassy_stm32::rcc::*;
        config.rcc.hsi = Some(HSIPrescaler::DIV1);
        config.rcc.csi = true;
        config.rcc.pll1 = Some(Pll {
            source: PllSource::HSI,
            prediv: PllPreDiv::DIV4,
            mul: PllMul::MUL50,
            divp: Some(PllDiv::DIV2),
            divq: Some(PllDiv::DIV8), // used by SPI3. 100Mhz.
            divr: None,
        });
        config.rcc.sys = Sysclk::PLL1_P; // 400 Mhz
        config.rcc.ahb_pre = AHBPrescaler::DIV2; // 200 Mhz
        config.rcc.apb1_pre = APBPrescaler::DIV2; // 100 Mhz
        config.rcc.apb2_pre = APBPrescaler::DIV2; // 100 Mhz
        config.rcc.apb3_pre = APBPrescaler::DIV2; // 100 Mhz
        config.rcc.apb4_pre = APBPrescaler::DIV2; // 100 Mhz
        config.rcc.voltage_scale = VoltageScale::Scale1;
    }
    let p = embassy_stm32::init(config);

    let mut spi_config = spi::Config::default();
    spi_config.frequency = mhz(1);

    let spi = spi::Spi::new(p.SPI3, p.PB3, p.PB5, p.PB4, NoDma, NoDma, spi_config);

    let executor = EXECUTOR.init(Executor::new());

    executor.run(|spawner| {
        unwrap!(spawner.spawn(main_task(spi)));
    })
}