wip: esp-hosted net driver.

1 files changed, 300 insertions, 0 deletions

diff --git a/embassy-net-esp-hosted/src/lib.rs b/embassy-net-esp-hosted/src/lib.rs
new file mode 100644
index 000000000..2cf05a7df
--- /dev/null
+++ b/embassy-net-esp-hosted/src/lib.rs
@@ -0,0 +1,300 @@
+#![no_std]
+
+use control::Control;
+use embassy_futures::select::{select3, Either3};
+use embassy_net_driver_channel as ch;
+use embassy_time::{Duration, Instant, Timer};
+use embedded_hal::digital::{InputPin, OutputPin};
+use embedded_hal_async::digital::Wait;
+use embedded_hal_async::spi::SpiDevice;
+use ioctl::IoctlState;
+
+use crate::ioctl::PendingIoctl;
+
+mod proto;
+
+// must be first
+mod fmt;
+
+mod control;
+mod ioctl;
+
+const MTU: usize = 1514;
+
+macro_rules! impl_bytes {
+    ($t:ident) => {
+        impl $t {
+            pub const SIZE: usize = core::mem::size_of::<Self>();
+
+            #[allow(unused)]
+            pub fn to_bytes(&self) -> [u8; Self::SIZE] {
+                unsafe { core::mem::transmute(*self) }
+            }
+
+            #[allow(unused)]
+            pub fn from_bytes(bytes: &[u8; Self::SIZE]) -> &Self {
+                let alignment = core::mem::align_of::<Self>();
+                assert_eq!(
+                    bytes.as_ptr().align_offset(alignment),
+                    0,
+                    "{} is not aligned",
+                    core::any::type_name::<Self>()
+                );
+                unsafe { core::mem::transmute(bytes) }
+            }
+
+            #[allow(unused)]
+            pub fn from_bytes_mut(bytes: &mut [u8; Self::SIZE]) -> &mut Self {
+                let alignment = core::mem::align_of::<Self>();
+                assert_eq!(
+                    bytes.as_ptr().align_offset(alignment),
+                    0,
+                    "{} is not aligned",
+                    core::any::type_name::<Self>()
+                );
+
+                unsafe { core::mem::transmute(bytes) }
+            }
+        }
+    };
+}
+
+#[repr(C, packed)]
+#[derive(Clone, Copy, Debug, Default)]
+struct PayloadHeader {
+    /// InterfaceType on lower 4 bits, number on higher 4 bits.
+    if_type_and_num: u8,
+
+    /// Flags.
+    ///
+    /// bit 0: more fragments.
+    flags: u8,
+
+    len: u16,
+    offset: u16,
+    checksum: u16,
+    seq_num: u16,
+    reserved2: u8,
+
+    /// Packet type for HCI or PRIV interface, reserved otherwise
+    hci_priv_packet_type: u8,
+}
+impl_bytes!(PayloadHeader);
+
+#[repr(u8)]
+enum InterfaceType {
+    Sta = 0,
+    Ap = 1,
+    Serial = 2,
+    Hci = 3,
+    Priv = 4,
+    Test = 5,
+}
+
+const MAX_SPI_BUFFER_SIZE: usize = 1600;
+
+pub struct State {
+    ioctl_state: IoctlState,
+    ch: ch::State<MTU, 4, 4>,
+}
+
+impl State {
+    pub fn new() -> Self {
+        Self {
+            ioctl_state: IoctlState::new(),
+            ch: ch::State::new(),
+        }
+    }
+}
+
+pub type NetDriver<'a> = ch::Device<'a, MTU>;
+
+pub async fn new<'a, SPI, IN, OUT>(
+    state: &'a mut State,
+    spi: SPI,
+    handshake: IN,
+    ready: IN,
+    reset: OUT,
+) -> (NetDriver<'a>, Control<'a>, Runner<'a, SPI, IN, OUT>)
+where
+    SPI: SpiDevice,
+    IN: InputPin + Wait,
+    OUT: OutputPin,
+{
+    let (ch_runner, device) = ch::new(&mut state.ch, [0; 6]);
+    let state_ch = ch_runner.state_runner();
+
+    let mut runner = Runner {
+        ch: ch_runner,
+        ioctl_state: &state.ioctl_state,
+        next_seq: 1,
+        handshake,
+        ready,
+        reset,
+        spi,
+    };
+    runner.init().await;
+
+    (device, Control::new(state_ch, &state.ioctl_state), runner)
+}
+
+pub struct Runner<'a, SPI, IN, OUT> {
+    ch: ch::Runner<'a, MTU>,
+    ioctl_state: &'a IoctlState,
+
+    next_seq: u16,
+
+    spi: SPI,
+    handshake: IN,
+    ready: IN,
+    reset: OUT,
+}
+
+impl<'a, SPI, IN, OUT> Runner<'a, SPI, IN, OUT>
+where
+    SPI: SpiDevice,
+    IN: InputPin + Wait,
+    OUT: OutputPin,
+{
+    async fn init(&mut self) {}
+
+    pub async fn run(mut self) -> ! {
+        debug!("resetting...");
+        self.reset.set_low().unwrap();
+        Timer::after(Duration::from_millis(100)).await;
+        self.reset.set_high().unwrap();
+        Timer::after(Duration::from_millis(1000)).await;
+
+        let mut tx_buf = [0u8; MAX_SPI_BUFFER_SIZE];
+        let mut rx_buf = [0u8; MAX_SPI_BUFFER_SIZE];
+
+        loop {
+            self.handshake.wait_for_high().await.unwrap();
+
+            let ioctl = self.ioctl_state.wait_pending();
+            let tx = self.ch.tx_buf();
+            let ev = async { self.ready.wait_for_high().await.unwrap() };
+
+            match select3(ioctl, tx, ev).await {
+                Either3::First(PendingIoctl { buf, req_len }) => {
+                    tx_buf[12..24].copy_from_slice(b"\x01\x08\x00ctrlResp\x02");
+                    tx_buf[24..26].copy_from_slice(&(req_len as u16).to_le_bytes());
+                    tx_buf[26..][..req_len].copy_from_slice(&unsafe { &*buf }[..req_len]);
+
+                    let mut header = PayloadHeader {
+                        if_type_and_num: InterfaceType::Serial as _,
+                        len: (req_len + 14) as _,
+                        offset: PayloadHeader::SIZE as _,
+                        seq_num: self.next_seq,
+                        ..Default::default()
+                    };
+                    self.next_seq = self.next_seq.wrapping_add(1);
+
+                    // Calculate checksum
+                    tx_buf[0..12].copy_from_slice(&header.to_bytes());
+                    header.checksum = checksum(&tx_buf[..26 + req_len]);
+                    tx_buf[0..12].copy_from_slice(&header.to_bytes());
+
+                    debug!("====== SENDING IOCTL");
+                }
+                Either3::Second(packet) => {
+                    tx_buf[12..][..packet.len()].copy_from_slice(packet);
+
+                    let mut header = PayloadHeader {
+                        if_type_and_num: InterfaceType::Sta as _,
+                        len: packet.len() as _,
+                        offset: PayloadHeader::SIZE as _,
+                        seq_num: self.next_seq,
+                        ..Default::default()
+                    };
+                    self.next_seq = self.next_seq.wrapping_add(1);
+
+                    // Calculate checksum
+                    tx_buf[0..12].copy_from_slice(&header.to_bytes());
+                    header.checksum = checksum(&tx_buf[..12 + packet.len()]);
+                    tx_buf[0..12].copy_from_slice(&header.to_bytes());
+
+                    self.ch.tx_done();
+                }
+                Either3::Third(()) => {
+                    tx_buf[..PayloadHeader::SIZE].fill(0);
+                }
+            }
+
+            if tx_buf[0] != 0 {
+                trace!("tx: {:02x}", &tx_buf[..40]);
+            }
+
+            self.spi.transfer(&mut rx_buf, &tx_buf).await.unwrap();
+            let delay_until = Instant::now() + Duration::from_millis(1);
+            self.handle_rx(&mut rx_buf);
+            Timer::at(delay_until).await;
+        }
+    }
+
+    fn handle_rx(&mut self, buf: &mut [u8]) {
+        trace!("rx: {:02x}", &buf[..40]);
+
+        let buf_len = buf.len();
+        let h = PayloadHeader::from_bytes_mut((&mut buf[..PayloadHeader::SIZE]).try_into().unwrap());
+
+        if h.len == 0 || h.offset as usize != PayloadHeader::SIZE {
+            return;
+        }
+
+        let payload_len = h.len as usize;
+        if buf_len < PayloadHeader::SIZE + payload_len {
+            warn!("rx: len too big");
+            return;
+        }
+
+        let if_type_and_num = h.if_type_and_num;
+        let want_checksum = h.checksum;
+        h.checksum = 0;
+        let got_checksum = checksum(&buf[..PayloadHeader::SIZE + payload_len]);
+        if want_checksum != got_checksum {
+            warn!("rx: bad checksum. Got {:04x}, want {:04x}", got_checksum, want_checksum);
+            return;
+        }
+
+        let payload = &mut buf[PayloadHeader::SIZE..][..payload_len];
+
+        match if_type_and_num & 0x0f {
+            // STA
+            0 => match self.ch.try_rx_buf() {
+                Some(buf) => {
+                    buf[..payload.len()].copy_from_slice(payload);
+                    self.ch.rx_done(payload.len())
+                }
+                None => warn!("failed to push rxd packet to the channel."),
+            },
+            // serial
+            2 => {
+                debug!("serial rx: {:02x}", payload);
+                if payload.len() < 14 {
+                    warn!("serial rx: too short");
+                    return;
+                }
+                if &payload[..12] != b"\x01\x08\x00ctrlResp\x02" {
+                    warn!("serial rx: bad tlv");
+                    return;
+                }
+                let len = u16::from_le_bytes(payload[12..14].try_into().unwrap()) as usize;
+                if payload.len() < 14 + len {
+                    warn!("serial rx: too short 2");
+                    return;
+                }
+                self.ioctl_state.ioctl_done(&payload[14..][..len]);
+            }
+            _ => warn!("unknown iftype {}", if_type_and_num),
+        }
+    }
+}
+
+fn checksum(buf: &[u8]) -> u16 {
+    let mut res = 0u16;
+    for &b in buf {
+        res = res.wrapping_add(b as _);
+    }
+    res
+}