raspberry_pi_pico_2/

main.rs

// Licensed under the Apache License, Version 2.0 or the MIT License.
// SPDX-License-Identifier: Apache-2.0 OR MIT
// Copyright OxidOS Automotive 2025.

//! Tock kernel for the Raspberry Pi Pico 2.
//!
//! It is based on RP2350SoC SoC (Cortex M33).

#![no_std]
// Disable this attribute when documenting, as a workaround for
// https://github.com/rust-lang/rust/issues/62184.
#![cfg_attr(not(doc), no_main)]
#![deny(missing_docs)]

use core::ptr::addr_of_mut;

use capsules_core::virtualizers::virtual_alarm::VirtualMuxAlarm;
use components::gpio::GpioComponent;
use components::led::LedsComponent;
use enum_primitive::cast::FromPrimitive;
use kernel::component::Component;
use kernel::hil::led::LedHigh;
use kernel::platform::{KernelResources, SyscallDriverLookup};
use kernel::process::ProcessArray;
use kernel::scheduler::round_robin::RoundRobinSched;
use kernel::syscall::SyscallDriver;
use kernel::{capabilities, create_capability, static_init, Kernel};

use rp2350::chip::{Rp2350, Rp2350DefaultPeripherals};
use rp2350::clocks::{
    AdcAuxiliaryClockSource, HstxAuxiliaryClockSource, PeripheralAuxiliaryClockSource, PllClock,
    ReferenceAuxiliaryClockSource, ReferenceClockSource, SystemAuxiliaryClockSource,
    SystemClockSource, UsbAuxiliaryClockSource,
};
use rp2350::gpio::{GpioFunction, RPGpio, RPGpioPin};
use rp2350::resets::Peripheral;
use rp2350::timer::RPTimer;
#[allow(unused)]
use rp2350::{xosc, BASE_VECTORS};

mod io;

mod flash_bootloader;

/// Allocate memory for the stack
//
// When compiling for a macOS host, the `link_section` attribute is elided as
// it yields the following error: `mach-o section specifier requires a segment
// and section separated by a comma`.
#[cfg_attr(not(target_os = "macos"), link_section = ".stack_buffer")]
#[no_mangle]
static mut STACK_MEMORY: [u8; 0x3000] = [0; 0x3000];

// Manually setting the boot header section that contains the FCB header
//
// When compiling for a macOS host, the `link_section` attribute is elided as
// it yields the following error: `mach-o section specifier requires a segment
// and section separated by a comma`.
#[cfg_attr(not(target_os = "macos"), link_section = ".flash_bootloader")]
#[used]
static FLASH_BOOTLOADER: [u8; 256] = flash_bootloader::FLASH_BOOTLOADER;

// When compiling for a macOS host, the `link_section` attribute is elided as
// it yields the following error: `mach-o section specifier requires a segment
// and section separated by a comma`.
#[cfg_attr(not(target_os = "macos"), link_section = ".metadata_block")]
#[used]
static METADATA_BLOCK: [u8; 28] = flash_bootloader::METADATA_BLOCK;

// State for loading and holding applications.
// How should the kernel respond when a process faults.
const FAULT_RESPONSE: capsules_system::process_policies::PanicFaultPolicy =
    capsules_system::process_policies::PanicFaultPolicy {};

// Number of concurrent processes this platform supports.
const NUM_PROCS: usize = 4;

type ChipHw = Rp2350<'static, Rp2350DefaultPeripherals<'static>>;

/// Static variables used by io.rs.
static mut PROCESSES: Option<&'static ProcessArray<NUM_PROCS>> = None;

static mut CHIP: Option<&'static Rp2350<Rp2350DefaultPeripherals<'static>>> = None;
static mut PROCESS_PRINTER: Option<&'static capsules_system::process_printer::ProcessPrinterText> =
    None;

/// Supported drivers by the platform
pub struct RaspberryPiPico2 {
    ipc: kernel::ipc::IPC<{ NUM_PROCS as u8 }>,
    console: &'static capsules_core::console::Console<'static>,
    scheduler: &'static RoundRobinSched<'static>,
    systick: cortexm33::systick::SysTick,
    alarm: &'static capsules_core::alarm::AlarmDriver<
        'static,
        VirtualMuxAlarm<'static, rp2350::timer::RPTimer<'static>>,
    >,
    gpio: &'static capsules_core::gpio::GPIO<'static, RPGpioPin<'static>>,
    led: &'static capsules_core::led::LedDriver<'static, LedHigh<'static, RPGpioPin<'static>>, 1>,
}

impl SyscallDriverLookup for RaspberryPiPico2 {
    fn with_driver<F, R>(&self, driver_num: usize, f: F) -> R
    where
        F: FnOnce(Option<&dyn SyscallDriver>) -> R,
    {
        match driver_num {
            capsules_core::console::DRIVER_NUM => f(Some(self.console)),
            capsules_core::alarm::DRIVER_NUM => f(Some(self.alarm)),
            capsules_core::gpio::DRIVER_NUM => f(Some(self.gpio)),
            capsules_core::led::DRIVER_NUM => f(Some(self.led)),
            kernel::ipc::DRIVER_NUM => f(Some(&self.ipc)),
            _ => f(None),
        }
    }
}

impl KernelResources<Rp2350<'static, Rp2350DefaultPeripherals<'static>>> for RaspberryPiPico2 {
    type SyscallDriverLookup = Self;
    type SyscallFilter = ();
    type ProcessFault = ();
    type Scheduler = RoundRobinSched<'static>;
    type SchedulerTimer = cortexm33::systick::SysTick;
    type WatchDog = ();
    type ContextSwitchCallback = ();

    fn syscall_driver_lookup(&self) -> &Self::SyscallDriverLookup {
        self
    }
    fn syscall_filter(&self) -> &Self::SyscallFilter {
        &()
    }
    fn process_fault(&self) -> &Self::ProcessFault {
        &()
    }
    fn scheduler(&self) -> &Self::Scheduler {
        self.scheduler
    }
    fn scheduler_timer(&self) -> &Self::SchedulerTimer {
        &self.systick
    }
    fn watchdog(&self) -> &Self::WatchDog {
        &()
    }
    fn context_switch_callback(&self) -> &Self::ContextSwitchCallback {
        &()
    }
}

#[allow(dead_code)]
extern "C" {
    /// Entry point used for debugger
    ///
    /// When loaded using gdb, the Raspberry Pi Pico 2 is not reset
    /// by default. Without this function, gdb sets the PC to the
    /// beginning of the flash. This is not correct, as the RP2350
    /// has a more complex boot process.
    ///
    /// This function is set to be the entry point for gdb and is used
    /// to send the RP2350 back in the bootloader so that all the boot
    /// sequence is performed.
    fn jump_to_bootloader();
}

#[cfg(any(doc, all(target_arch = "arm", target_os = "none")))]
core::arch::global_asm!(
    "
    .section .jump_to_bootloader, \"ax\"
    .global jump_to_bootloader
    .thumb_func
  jump_to_bootloader:
    movs r0, #0
    ldr r1, =(0xe0000000 + 0x0000ed08)
    str r0, [r1]
    ldmia r0!, {{r1, r2}}
    msr msp, r1
    bx r2
    "
);

fn init_clocks(peripherals: &Rp2350DefaultPeripherals) {
    // // Start tick in watchdog
    // peripherals.watchdog.start_tick(12);
    //
    // Disable the Resus clock
    peripherals.clocks.disable_resus();

    // Setup the external Oscillator
    peripherals.xosc.init();

    // disable ref and sys clock aux sources
    peripherals.clocks.disable_sys_aux();
    peripherals.clocks.disable_ref_aux();

    peripherals
        .resets
        .reset(&[Peripheral::PllSys, Peripheral::PllUsb]);
    peripherals
        .resets
        .unreset(&[Peripheral::PllSys, Peripheral::PllUsb], true);

    // Configure PLLs (from Pico SDK)
    //                   REF     FBDIV VCO            POSTDIV
    // PLL SYS: 12 / 1 = 12MHz * 125 = 1500MHZ / 6 / 2 = 125MHz
    // PLL USB: 12 / 1 = 12MHz * 40  = 480 MHz / 5 / 2 =  48MHz

    // It seems that the external oscillator is clocked at 12 MHz

    peripherals
        .clocks
        .pll_init(PllClock::Sys, 12, 1, 1500 * 1000000, 6, 2);
    peripherals
        .clocks
        .pll_init(PllClock::Usb, 12, 1, 480 * 1000000, 5, 2);

    // pico-sdk: // CLK_REF = XOSC (12MHz) / 1 = 12MHz
    peripherals.clocks.configure_reference(
        ReferenceClockSource::Xosc,
        ReferenceAuxiliaryClockSource::PllUsb,
        12000000,
        12000000,
    );
    // pico-sdk: CLK SYS = PLL SYS (125MHz) / 1 = 125MHz
    peripherals.clocks.configure_system(
        SystemClockSource::Auxiliary,
        SystemAuxiliaryClockSource::PllSys,
        125000000,
        125000000,
    );

    // pico-sdk: CLK USB = PLL USB (48MHz) / 1 = 48MHz
    peripherals
        .clocks
        .configure_usb(UsbAuxiliaryClockSource::PllSys, 48000000, 48000000);
    // pico-sdk: CLK ADC = PLL USB (48MHZ) / 1 = 48MHz
    peripherals
        .clocks
        .configure_adc(AdcAuxiliaryClockSource::PllUsb, 48000000, 48000000);
    // pico-sdk: CLK HSTX = PLL USB (48MHz) / 1024 = 46875Hz
    peripherals
        .clocks
        .configure_hstx(HstxAuxiliaryClockSource::PllSys, 48000000, 46875);
    // pico-sdk:
    // CLK PERI = clk_sys. Used as reference clock for Peripherals. No dividers so just select and enable
    // Normally choose clk_sys or clk_usb
    peripherals
        .clocks
        .configure_peripheral(PeripheralAuxiliaryClockSource::System, 125000000);
}

unsafe fn get_peripherals() -> &'static mut Rp2350DefaultPeripherals<'static> {
    static_init!(Rp2350DefaultPeripherals, Rp2350DefaultPeripherals::new())
}

/// Main function called after RAM initialized.
#[no_mangle]
pub unsafe fn main() {
    rp2350::init();

    // Initialize deferred calls very early.
    kernel::deferred_call::initialize_deferred_call_state::<
        <ChipHw as kernel::platform::chip::Chip>::ThreadIdProvider,
    >();

    let peripherals = get_peripherals();
    peripherals.resolve_dependencies();

    peripherals.resets.reset_all_except(&[
        Peripheral::IOQSpi,
        Peripheral::PadsQSpi,
        Peripheral::PllUsb,
        Peripheral::PllSys,
    ]);

    init_clocks(peripherals);

    peripherals.resets.unreset_all_except(&[], true);

    // Set the UART used for panic
    (*addr_of_mut!(io::WRITER)).set_uart(&peripherals.uart0);

    let gpio_tx = peripherals.pins.get_pin(RPGpio::GPIO0);
    let gpio_rx = peripherals.pins.get_pin(RPGpio::GPIO1);
    gpio_rx.set_function(GpioFunction::UART);
    gpio_tx.set_function(GpioFunction::UART);

    //// Disable IE for pads 26-29 (the Pico SDK runtime does this, not sure why)
    for pin in 26..30 {
        peripherals
            .pins
            .get_pin(RPGpio::from_usize(pin).unwrap())
            .deactivate_pads();
    }

    let chip = static_init!(
        Rp2350<Rp2350DefaultPeripherals>,
        Rp2350::new(peripherals, &peripherals.sio)
    );

    CHIP = Some(chip);

    // Create an array to hold process references.
    let processes = components::process_array::ProcessArrayComponent::new()
        .finalize(components::process_array_component_static!(NUM_PROCS));
    PROCESSES = Some(processes);

    let board_kernel = static_init!(Kernel, Kernel::new(processes.as_slice()));

    let process_management_capability =
        create_capability!(capabilities::ProcessManagementCapability);
    let memory_allocation_capability = create_capability!(capabilities::MemoryAllocationCapability);

    let mux_alarm = components::alarm::AlarmMuxComponent::new(&peripherals.timer0)
        .finalize(components::alarm_mux_component_static!(RPTimer));

    let alarm = components::alarm::AlarmDriverComponent::new(
        board_kernel,
        capsules_core::alarm::DRIVER_NUM,
        mux_alarm,
    )
    .finalize(components::alarm_component_static!(RPTimer));

    let uart_mux = components::console::UartMuxComponent::new(&peripherals.uart0, 115200)
        .finalize(components::uart_mux_component_static!());

    // Setup the console.
    let console = components::console::ConsoleComponent::new(
        board_kernel,
        capsules_core::console::DRIVER_NUM,
        uart_mux,
    )
    .finalize(components::console_component_static!());

    let gpio = GpioComponent::new(
        board_kernel,
        capsules_core::gpio::DRIVER_NUM,
        components::gpio_component_helper!(
            RPGpioPin,
            // Used for serial communication. Comment them in if you don't use serial.
            // 0 => peripherals.pins.get_pin(RPGpio::GPIO0),
            // 1 => peripherals.pins.get_pin(RPGpio::GPIO1),
            2 => peripherals.pins.get_pin(RPGpio::GPIO2),
            3 => peripherals.pins.get_pin(RPGpio::GPIO3),
            4 => peripherals.pins.get_pin(RPGpio::GPIO4),
            5 => peripherals.pins.get_pin(RPGpio::GPIO5),
            6 => peripherals.pins.get_pin(RPGpio::GPIO6),
            7 => peripherals.pins.get_pin(RPGpio::GPIO7),
            8 => peripherals.pins.get_pin(RPGpio::GPIO8),
            9 => peripherals.pins.get_pin(RPGpio::GPIO9),
            10 => peripherals.pins.get_pin(RPGpio::GPIO10),
            11 => peripherals.pins.get_pin(RPGpio::GPIO11),
            12 => peripherals.pins.get_pin(RPGpio::GPIO12),
            13 => peripherals.pins.get_pin(RPGpio::GPIO13),
            14 => peripherals.pins.get_pin(RPGpio::GPIO14),
            15 => peripherals.pins.get_pin(RPGpio::GPIO15),
            16 => peripherals.pins.get_pin(RPGpio::GPIO16),
            17 => peripherals.pins.get_pin(RPGpio::GPIO17),
            18 => peripherals.pins.get_pin(RPGpio::GPIO18),
            19 => peripherals.pins.get_pin(RPGpio::GPIO19),
            20 => peripherals.pins.get_pin(RPGpio::GPIO20),
            21 => peripherals.pins.get_pin(RPGpio::GPIO21),
            22 => peripherals.pins.get_pin(RPGpio::GPIO22),
            23 => peripherals.pins.get_pin(RPGpio::GPIO23),
            24 => peripherals.pins.get_pin(RPGpio::GPIO24),
            // LED pin
            // 25 => peripherals.pins.get_pin(RPGpio::GPIO25),
            26 => peripherals.pins.get_pin(RPGpio::GPIO26),
            27 => peripherals.pins.get_pin(RPGpio::GPIO27),
            28 => peripherals.pins.get_pin(RPGpio::GPIO28),
            29 => peripherals.pins.get_pin(RPGpio::GPIO29)
        ),
    )
    .finalize(components::gpio_component_static!(RPGpioPin<'static>));

    let led = LedsComponent::new().finalize(components::led_component_static!(
        LedHigh<'static, RPGpioPin<'static>>,
        LedHigh::new(peripherals.pins.get_pin(RPGpio::GPIO25))
    ));

    // Create the debugger object that handles calls to `debug!()`.
    components::debug_writer::DebugWriterComponent::new::<
        <ChipHw as kernel::platform::chip::Chip>::ThreadIdProvider,
    >(
        uart_mux,
        create_capability!(capabilities::SetDebugWriterCapability),
    )
    .finalize(components::debug_writer_component_static!());

    // PROCESS CONSOLE
    let process_printer = components::process_printer::ProcessPrinterTextComponent::new()
        .finalize(components::process_printer_text_component_static!());
    PROCESS_PRINTER = Some(process_printer);

    let process_console = components::process_console::ProcessConsoleComponent::new(
        board_kernel,
        uart_mux,
        mux_alarm,
        process_printer,
        Some(cortexm33::support::reset),
    )
    .finalize(components::process_console_component_static!(RPTimer));
    let _ = process_console.start();

    let scheduler = components::sched::round_robin::RoundRobinComponent::new(processes)
        .finalize(components::round_robin_component_static!(NUM_PROCS));

    let raspberry_pi_pico = RaspberryPiPico2 {
        ipc: kernel::ipc::IPC::new(
            board_kernel,
            kernel::ipc::DRIVER_NUM,
            &memory_allocation_capability,
        ),
        console,
        alarm,
        gpio,
        led,
        scheduler,
        systick: cortexm33::systick::SysTick::new_with_calibration(125_000_000),
    };

    kernel::debug!("Initialization complete. Enter main loop");

    // These symbols are defined in the linker script.
    extern "C" {
        /// Beginning of the ROM region containing app images.
        static _sapps: u8;
        /// End of the ROM region containing app images.
        static _eapps: u8;
        /// Beginning of the RAM region for app memory.
        static mut _sappmem: u8;
        /// End of the RAM region for app memory.
        static _eappmem: u8;
    }

    kernel::process::load_processes(
        board_kernel,
        chip,
        core::slice::from_raw_parts(
            core::ptr::addr_of!(_sapps),
            core::ptr::addr_of!(_eapps) as usize - core::ptr::addr_of!(_sapps) as usize,
        ),
        core::slice::from_raw_parts_mut(
            core::ptr::addr_of_mut!(_sappmem),
            core::ptr::addr_of!(_eappmem) as usize - core::ptr::addr_of!(_sappmem) as usize,
        ),
        &FAULT_RESPONSE,
        &process_management_capability,
    )
    .unwrap_or_else(|err| {
        kernel::debug!("Error loading processes!");
        kernel::debug!("{:?}", err);
    });

    let main_loop_capability = create_capability!(capabilities::MainLoopCapability);

    board_kernel.kernel_loop(
        &raspberry_pi_pico,
        chip,
        Some(&raspberry_pi_pico.ipc),
        &main_loop_capability,
    );
}