default.nix

@@ -20,7 +20,7 @@ let
       name = "firmware";
 
       src = ./src;
-      cargoSha256 = "0p9d2j7qp00wpxm48phl5rq26simzry6w0m673lyhrlbzqdz4frb";
+      cargoSha256 = "sha256-uiwESZNwPdVnDkA1n0v1DQHp3rTazDkgIYscVTpgNq0=";
 
       nativeBuildInputs = [
         pkgs.gnumake

src/libboard_artiq/Cargo.toml

@@ -0,0 +1,31 @@
+[package]
+name = "libboard_artiq"
+version = "0.0.0"
+authors = ["M-Labs"]
+edition = "2018"
+
+[lib]
+name = "libboard_artiq"
+
+[features]
+target_zc706 = []
+target_kasli_soc = []
+
+[build-dependencies]
+build_zynq = { path = "../libbuild_zynq" }
+
+[dependencies]
+log = "0.4"
+log_buffer = { version = "1.2" }
+crc = { version = "1.7", default-features = false }
+core_io = { version = "0.1", features = ["collections"] }
+embedded-hal = "0.2"
+nb = "1.0"
+void = { version = "1", default-features = false }
+
+io = { path = "../libio", features = ["byteorder"] }
+libboard_zynq = { git = "https://git.m-labs.hk/M-Labs/zynq-rs.git"}
+libregister = { git = "https://git.m-labs.hk/M-Labs/zynq-rs.git" }
+libconfig = { git = "https://git.m-labs.hk/M-Labs/zynq-rs.git"}
+libcortex_a9 = { git = "https://git.m-labs.hk/M-Labs/zynq-rs.git" }
+libasync = { git = "https://git.m-labs.hk/M-Labs/zynq-rs.git" }

src/libboard_artiq/build.rs

@@ -0,0 +1,5 @@
+extern crate build_zynq;
+
+fn main() {
+    build_zynq::cfg();
+}

src/libboard_artiq/src/drtio_routing.rs

@@ -0,0 +1,109 @@
+use libconfig::Config;
+#[cfg(has_drtio_routing)]
+use crate::pl::csr;
+use core::fmt;
+
+use log::{warn, info};
+
+#[cfg(has_drtio_routing)]
+pub const DEST_COUNT: usize = 256;
+#[cfg(not(has_drtio_routing))]
+pub const DEST_COUNT: usize = 0;
+pub const MAX_HOPS: usize = 32;
+pub const INVALID_HOP: u8 = 0xff;
+
+pub struct RoutingTable(pub [[u8; MAX_HOPS]; DEST_COUNT]);
+
+impl RoutingTable {
+    // default routing table is for star topology with no repeaters
+    pub fn default_master(default_n_links: usize) -> RoutingTable {
+        let mut ret = RoutingTable([[INVALID_HOP; MAX_HOPS]; DEST_COUNT]);
+        let n_entries = default_n_links + 1;  // include local RTIO
+        for i in 0..n_entries {
+            ret.0[i][0] = i as u8;
+        }
+        for i in 1..n_entries {
+            ret.0[i][1] = 0x00;
+        }
+        ret
+    }
+
+    // use this by default on satellite, as they receive
+    // the routing table from the master
+    pub fn default_empty() -> RoutingTable {
+        RoutingTable([[INVALID_HOP; MAX_HOPS]; DEST_COUNT])
+    }
+}
+
+impl fmt::Display for RoutingTable {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "RoutingTable {{")?;
+        for i in 0..DEST_COUNT {
+            if self.0[i][0] != INVALID_HOP {
+                write!(f, " {}:", i)?;
+                for j in 0..MAX_HOPS {
+                    if self.0[i][j] == INVALID_HOP {
+                        break;
+                    }
+                    write!(f, " {}", self.0[i][j])?;
+                }
+                write!(f, ";")?;
+            }
+        }
+        write!(f, " }}")?;
+        Ok(())
+    }
+}
+
+pub fn config_routing_table(default_n_links: usize, cfg: &Config) -> RoutingTable {
+    let mut ret = RoutingTable::default_master(default_n_links);
+    if let Ok(data) = cfg.read("routing_table") {
+        if data.len() == DEST_COUNT*MAX_HOPS
+        {
+            for i in 0..DEST_COUNT {
+                for j in 0..MAX_HOPS {
+                    ret.0[i][j] = data[i*MAX_HOPS+j];
+                }
+            }
+        }
+        else {
+            warn!("length of the routing table is incorrect, using default");
+        }
+    }
+    else {
+        warn!("could not read routing table from configuration, using default");
+    }
+    info!("routing table: {}", ret);
+    ret
+}
+
+#[cfg(has_drtio_routing)]
+pub fn interconnect_enable(routing_table: &RoutingTable, rank: u8, destination: u8) {
+    let hop = routing_table.0[destination as usize][rank as usize];
+    unsafe {
+        csr::routing_table::destination_write(destination);
+        csr::routing_table::hop_write(hop);
+    }
+}
+
+#[cfg(has_drtio_routing)]
+pub fn interconnect_disable(destination: u8) {
+    unsafe {
+        csr::routing_table::destination_write(destination);
+        csr::routing_table::hop_write(INVALID_HOP);
+    }
+}
+
+#[cfg(has_drtio_routing)]
+pub fn interconnect_enable_all(routing_table: &RoutingTable, rank: u8) {
+    for i in 0..DEST_COUNT {
+        interconnect_enable(routing_table, rank, i as u8);
+    }
+}
+
+#[cfg(has_drtio_routing)]
+pub fn interconnect_disable_all() {
+    for i in 0..DEST_COUNT {
+        interconnect_disable(i as u8);
+    }
+}

src/libboard_artiq/src/drtioaux.rs

@@ -0,0 +1,174 @@
+use crc;
+
+use core_io::{ErrorKind as IoErrorKind, Error as IoError};
+
+use io::{proto::ProtoRead, proto::ProtoWrite, Cursor};
+use libboard_zynq::{timer::GlobalTimer, time::Milliseconds};
+use crate::mem::mem::DRTIOAUX_MEM;
+use crate::pl::csr::DRTIOAUX;
+use crate::drtioaux_proto::Error as ProtocolError;
+
+pub use crate::drtioaux_proto::Packet;
+
+#[derive(Debug)]
+pub enum Error {
+    GatewareError,
+    CorruptedPacket,
+
+    LinkDown,
+    TimedOut,
+    UnexpectedReply,
+
+    RoutingError,
+
+    Protocol(ProtocolError)
+}
+
+impl From<ProtocolError> for Error {
+    fn from(value: ProtocolError) -> Error {
+        Error::Protocol(value)
+    }
+}
+
+impl From<IoError> for Error {
+    fn from(value: IoError) -> Error {
+        Error::Protocol(ProtocolError::Io(value))
+    }
+}
+
+pub fn reset(linkno: u8) {
+    let linkno = linkno as usize;
+    unsafe {
+        // clear buffer first to limit race window with buffer overflow
+        // error. We assume the CPU is fast enough so that no two packets
+        // will be received between the buffer and the error flag are cleared.
+        (DRTIOAUX[linkno].aux_rx_present_write)(1);
+        (DRTIOAUX[linkno].aux_rx_error_write)(1);
+    }
+}
+
+pub fn has_rx_error(linkno: u8) -> bool {
+    let linkno = linkno as usize;
+    unsafe {
+        let error = (DRTIOAUX[linkno].aux_rx_error_read)() != 0;
+        if error {
+            (DRTIOAUX[linkno].aux_rx_error_write)(1)
+        }
+        error
+    }
+}
+
+pub fn copy_with_swap(src: *mut u8, dst: *mut u8, len: isize) {
+    // for some reason, everything except checksum arrives
+    // with byte order swapped. and it must be sent as such too.
+    unsafe {
+        for i in (0..(len-4)).step_by(4) {
+            *dst.offset(i) = *src.offset(i+3);
+            *dst.offset(i+1) = *src.offset(i+2);
+            *dst.offset(i+2) = *src.offset(i+1);
+            *dst.offset(i+3) = *src.offset(i);
+        }
+        // checksum untouched
+        // unrolled for performance
+        *dst.offset(len-4) = *src.offset(len-4);
+        *dst.offset(len-3) = *src.offset(len-3);
+        *dst.offset(len-2) = *src.offset(len-2);
+        *dst.offset(len-1) = *src.offset(len-1);
+    }
+}
+
+fn receive<F, T>(linkno: u8, f: F) -> Result<Option<T>, Error>
+    where F: FnOnce(&[u8]) -> Result<T, Error>
+{
+    let linkidx = linkno as usize;
+    unsafe {
+        if (DRTIOAUX[linkidx].aux_rx_present_read)() == 1 {
+            let ptr = (DRTIOAUX_MEM[linkidx].base + DRTIOAUX_MEM[linkidx].size / 2) as *mut u8;
+            let len = (DRTIOAUX[linkidx].aux_rx_length_read)() as usize;
+            // work buffer, as byte order will need to be swapped, cannot be in place
+            let mut buf: [u8; 1024] = [0; 1024];
+            copy_with_swap(ptr, buf.as_mut_ptr(), len as isize);
+            let result = f(&buf[0..len]);
+            (DRTIOAUX[linkidx].aux_rx_present_write)(1);
+            Ok(Some(result?))
+        } else {
+            Ok(None)
+        }
+    }
+}
+
+pub fn recv(linkno: u8) -> Result<Option<Packet>, Error> {
+    if has_rx_error(linkno) {
+        return Err(Error::GatewareError)
+    }
+
+    receive(linkno, |buffer| {
+        if buffer.len() < 8 {
+            return Err(IoError::new(IoErrorKind::UnexpectedEof, "Unexpected end").into())
+        }
+
+        let mut reader = Cursor::new(buffer);
+
+        let checksum_at = buffer.len() - 4;
+        let checksum = crc::crc32::checksum_ieee(&reader.get_ref()[0..checksum_at]);
+        reader.set_position(checksum_at);
+        if reader.read_u32()? != checksum {
+            return Err(Error::CorruptedPacket)
+        }
+        reader.set_position(0);
+
+        Ok(Packet::read_from(&mut reader)?)
+    })
+}
+
+pub fn recv_timeout(linkno: u8, timeout_ms: Option<u64>,
+    timer: GlobalTimer) -> Result<Packet, Error> 
+{
+    let timeout_ms = Milliseconds(timeout_ms.unwrap_or(10));
+    let limit = timer.get_time() + timeout_ms;
+    while timer.get_time() < limit {
+        match recv(linkno)? {
+            None => (),
+            Some(packet) => return Ok(packet),
+        }
+    }
+    Err(Error::TimedOut)
+}
+
+fn transmit<F>(linkno: u8, f: F) -> Result<(), Error>
+    where F: FnOnce(&mut [u8]) -> Result<usize, Error>
+{
+    let linkno = linkno as usize;
+    unsafe {
+        while (DRTIOAUX[linkno].aux_tx_read)() != 0 {}
+        let ptr = DRTIOAUX_MEM[linkno].base as *mut u8;
+        let len = DRTIOAUX_MEM[linkno].size / 2;
+        // work buffer, works with unaligned mem access
+        let mut buf: [u8; 1024] = [0; 1024]; 
+        let len = f(&mut buf[0..len])?;
+        copy_with_swap(buf.as_mut_ptr(), ptr, len as isize);
+        (DRTIOAUX[linkno].aux_tx_length_write)(len as u16);
+        (DRTIOAUX[linkno].aux_tx_write)(1);
+        Ok(())
+    }
+}
+
+pub fn send(linkno: u8, packet: &Packet) -> Result<(), Error> {
+    transmit(linkno, |buffer| {
+        let mut writer = Cursor::new(buffer);
+
+        packet.write_to(&mut writer)?;
+        
+        let padding = 4 - (writer.position() % 4);
+        if padding != 4 {
+            for _ in 0..padding {
+                writer.write_u8(0)?;
+            }
+        }
+
+        let checksum = crc::crc32::checksum_ieee(&writer.get_ref()[0..writer.position()]);
+        writer.write_u32(checksum)?;
+
+        Ok(writer.position())
+    })
+}

src/libboard_artiq/src/drtioaux_async.rs

@@ -0,0 +1,139 @@
+use crc;
+
+use core_io::{ErrorKind as IoErrorKind, Error as IoError};
+use void::Void;
+use nb;
+
+use libboard_zynq::{timer::GlobalTimer, time::Milliseconds};
+use libasync::{task, block_async};
+
+use io::{proto::ProtoRead, proto::ProtoWrite, Cursor};
+use crate::mem::mem::DRTIOAUX_MEM;
+use crate::pl::csr::DRTIOAUX;
+use crate::drtioaux::{Error, has_rx_error, copy_with_swap};
+
+pub use crate::drtioaux_proto::Packet;
+
+pub async fn reset(linkno: u8) {
+    let linkno = linkno as usize;
+    unsafe {
+        // clear buffer first to limit race window with buffer overflow
+        // error. We assume the CPU is fast enough so that no two packets
+        // will be received between the buffer and the error flag are cleared.
+        (DRTIOAUX[linkno].aux_rx_present_write)(1);
+        (DRTIOAUX[linkno].aux_rx_error_write)(1);
+    }
+}
+
+fn tx_ready(linkno: usize) -> nb::Result<(), Void> {
+    unsafe {
+        if (DRTIOAUX[linkno].aux_tx_read)() != 0 {
+            Err(nb::Error::WouldBlock)
+        }
+        else {
+            Ok(())
+        }
+    }
+}
+
+async fn receive<F, T>(linkno: u8, f: F) -> Result<Option<T>, Error>
+    where F: FnOnce(&[u8]) -> Result<T, Error>
+{
+    let linkidx = linkno as usize;
+    unsafe {
+        if (DRTIOAUX[linkidx].aux_rx_present_read)() == 1 {
+            let ptr = (DRTIOAUX_MEM[linkidx].base + DRTIOAUX_MEM[linkidx].size / 2) as *mut u8;
+            let len = (DRTIOAUX[linkidx].aux_rx_length_read)() as usize;
+            // work buffer, as byte order will need to be swapped, cannot be in place
+            let mut buf: [u8; 1024] = [0; 1024];
+            copy_with_swap(ptr, buf.as_mut_ptr(), len as isize);
+            let result = f(&buf[0..len]);
+            (DRTIOAUX[linkidx].aux_rx_present_write)(1);
+            Ok(Some(result?))
+        } else {
+            Ok(None)
+        }
+    }
+}
+
+pub async fn recv(linkno: u8) -> Result<Option<Packet>, Error> {
+    if has_rx_error(linkno) {
+        return Err(Error::GatewareError)
+    }
+
+    receive(linkno, |buffer| {
+        if buffer.len() < 8 {
+            return Err(IoError::new(IoErrorKind::UnexpectedEof, "Unexpected end").into())
+        }
+
+        let mut reader = Cursor::new(buffer);
+
+        let checksum_at = buffer.len() - 4;
+        let checksum = crc::crc32::checksum_ieee(&reader.get_ref()[0..checksum_at]);
+        reader.set_position(checksum_at);
+        if reader.read_u32()? != checksum {
+            return Err(Error::CorruptedPacket)
+        }
+        reader.set_position(0);
+
+        Ok(Packet::read_from(&mut reader)?)
+    }).await
+}
+
+pub async fn recv_timeout(linkno: u8, timeout_ms: Option<u64>,
+    timer: GlobalTimer) -> Result<Packet, Error> 
+{
+    let timeout_ms = Milliseconds(timeout_ms.unwrap_or(10));
+    let limit = timer.get_time() + timeout_ms;
+    let mut would_block = false;
+    while timer.get_time() < limit {
+        // to ensure one last time recv would run one last time
+        // in case async would return after timeout
+        if would_block {
+            task::r#yield().await;
+        }
+        match recv(linkno).await? {
+            None => { would_block = true; },
+            Some(packet) => return Ok(packet),
+        }
+    }
+    Err(Error::TimedOut)
+}
+
+async fn transmit<F>(linkno: u8, f: F) -> Result<(), Error>
+    where F: FnOnce(&mut [u8]) -> Result<usize, Error>
+{
+    let linkno = linkno as usize;
+    unsafe {
+        let _ = block_async!(tx_ready(linkno)).await;
+        let ptr = DRTIOAUX_MEM[linkno].base as *mut u8;
+        let len = DRTIOAUX_MEM[linkno].size / 2;
+        // work buffer, works with unaligned mem access
+        let mut buf: [u8; 1024] = [0; 1024]; 
+        let len = f(&mut buf[0..len])?;
+        copy_with_swap(buf.as_mut_ptr(), ptr, len as isize);
+        (DRTIOAUX[linkno].aux_tx_length_write)(len as u16);
+        (DRTIOAUX[linkno].aux_tx_write)(1);
+        Ok(())
+    }
+}
+
+pub async fn send(linkno: u8, packet: &Packet) -> Result<(), Error> {
+    transmit(linkno, |buffer| {
+        let mut writer = Cursor::new(buffer);
+
+        packet.write_to(&mut writer)?;
+        
+        let padding = 4 - (writer.position() % 4);
+        if padding != 4 {
+            for _ in 0..padding {
+                writer.write_u8(0)?;
+            }
+        }
+
+        let checksum = crc::crc32::checksum_ieee(&writer.get_ref()[0..writer.position()]);
+        writer.write_u32(checksum)?;
+
+        Ok(writer.position())
+    }).await
+}

src/libboard_artiq/src/drtioaux_proto.rs

@@ -0,0 +1,364 @@
+use core_io::{Write, Read, Error as IoError};
+
+use io::proto::{ProtoWrite, ProtoRead};
+
+#[derive(Debug)]
+pub enum Error {
+    UnknownPacket(u8),
+    Io(IoError)
+}
+
+impl From<IoError> for Error {
+    fn from(value: IoError) -> Error {
+        Error::Io(value)
+    }
+}
+
+#[derive(PartialEq, Debug)]
+pub enum Packet {
+    EchoRequest,
+    EchoReply,
+    ResetRequest,
+    ResetAck,
+    TSCAck,
+
+    DestinationStatusRequest { destination: u8 },
+    DestinationDownReply,
+    DestinationOkReply,
+    DestinationSequenceErrorReply { channel: u16 },
+    DestinationCollisionReply { channel: u16 },
+    DestinationBusyReply { channel: u16 },
+
+    RoutingSetPath { destination: u8, hops: [u8; 32] },
+    RoutingSetRank { rank: u8 },
+    RoutingAck,
+
+    MonitorRequest { destination: u8, channel: u16, probe: u8 },
+    MonitorReply { value: u32 },
+    InjectionRequest { destination: u8, channel: u16, overrd: u8, value: u8 },
+    InjectionStatusRequest { destination: u8, channel: u16, overrd: u8 },
+    InjectionStatusReply { value: u8 },
+
+    I2cStartRequest { destination: u8, busno: u8 },
+    I2cRestartRequest { destination: u8, busno: u8 },
+    I2cStopRequest { destination: u8, busno: u8 },
+    I2cWriteRequest { destination: u8, busno: u8, data: u8 },
+    I2cWriteReply { succeeded: bool, ack: bool },
+    I2cReadRequest { destination: u8, busno: u8, ack: bool },
+    I2cReadReply { succeeded: bool, data: u8 },
+    I2cBasicReply { succeeded: bool },
+
+    SpiSetConfigRequest { destination: u8, busno: u8, flags: u8, length: u8, div: u8, cs: u8 },
+    SpiWriteRequest { destination: u8, busno: u8, data: u32 },
+    SpiReadRequest { destination: u8, busno: u8 },
+    SpiReadReply { succeeded: bool, data: u32 },
+    SpiBasicReply { succeeded: bool },
+
+    JdacBasicRequest { destination: u8, dacno: u8, reqno: u8, param: u8 },
+    JdacBasicReply { succeeded: bool, retval: u8 },
+}
+
+impl Packet {
+    pub fn read_from<R>(reader: &mut R) -> Result<Self, Error>
+        where R: Read + ?Sized
+    {
+        Ok(match reader.read_u8()? {
+            0x00 => Packet::EchoRequest,
+            0x01 => Packet::EchoReply,
+            0x02 => Packet::ResetRequest,
+            0x03 => Packet::ResetAck,
+            0x04 => Packet::TSCAck,
+
+            0x20 => Packet::DestinationStatusRequest {
+                destination: reader.read_u8()?
+            },
+            0x21 => Packet::DestinationDownReply,
+            0x22 => Packet::DestinationOkReply,
+            0x23 => Packet::DestinationSequenceErrorReply {
+                channel: reader.read_u16()?
+            },
+            0x24 => Packet::DestinationCollisionReply {
+                channel: reader.read_u16()?
+            },
+            0x25 => Packet::DestinationBusyReply {
+                channel: reader.read_u16()?
+            },
+
+            0x30 => {
+                let destination = reader.read_u8()?;
+                let mut hops = [0; 32];
+                reader.read_exact(&mut hops)?;
+                Packet::RoutingSetPath {
+                    destination: destination,
+                    hops: hops
+                }
+            },
+            0x31 => Packet::RoutingSetRank {
+                rank: reader.read_u8()?
+            },
+            0x32 => Packet::RoutingAck,
+
+            0x40 => Packet::MonitorRequest {
+                destination: reader.read_u8()?,
+                channel: reader.read_u16()?,
+                probe: reader.read_u8()?
+            },
+            0x41 => Packet::MonitorReply {
+                value: reader.read_u32()?
+            },
+            0x50 => Packet::InjectionRequest {
+                destination: reader.read_u8()?,
+                channel: reader.read_u16()?,
+                overrd: reader.read_u8()?,
+                value: reader.read_u8()?
+            },
+            0x51 => Packet::InjectionStatusRequest {
+                destination: reader.read_u8()?,
+                channel: reader.read_u16()?,
+                overrd: reader.read_u8()?
+            },
+            0x52 => Packet::InjectionStatusReply {
+                value: reader.read_u8()?
+            },
+
+            0x80 => Packet::I2cStartRequest {
+                destination: reader.read_u8()?,
+                busno: reader.read_u8()?
+            },
+            0x81 => Packet::I2cRestartRequest {
+                destination: reader.read_u8()?,
+                busno: reader.read_u8()?
+            },
+            0x82 => Packet::I2cStopRequest {
+                destination: reader.read_u8()?,
+                busno: reader.read_u8()?
+            },
+            0x83 => Packet::I2cWriteRequest {
+                destination: reader.read_u8()?,
+                busno: reader.read_u8()?,
+                data: reader.read_u8()?
+            },
+            0x84 => Packet::I2cWriteReply {
+                succeeded: reader.read_bool()?,
+                ack: reader.read_bool()?
+            },
+            0x85 => Packet::I2cReadRequest {
+                destination: reader.read_u8()?,
+                busno: reader.read_u8()?,
+                ack: reader.read_bool()?
+            },
+            0x86 => Packet::I2cReadReply {
+                succeeded: reader.read_bool()?,
+                data: reader.read_u8()?
+            },
+            0x87 => Packet::I2cBasicReply {
+                succeeded: reader.read_bool()?
+            },
+
+            0x90 => Packet::SpiSetConfigRequest {
+                destination: reader.read_u8()?,
+                busno: reader.read_u8()?,
+                flags: reader.read_u8()?,
+                length: reader.read_u8()?,
+                div: reader.read_u8()?,
+                cs: reader.read_u8()?
+            },
+            /* 0x91: was Packet::SpiSetXferRequest */
+            0x92 => Packet::SpiWriteRequest {
+                destination: reader.read_u8()?,
+                busno: reader.read_u8()?,
+                data: reader.read_u32()?
+            },
+            0x93 => Packet::SpiReadRequest {
+                destination: reader.read_u8()?,
+                busno: reader.read_u8()?
+            },
+            0x94 => Packet::SpiReadReply {
+                succeeded: reader.read_bool()?,
+                data: reader.read_u32()?
+            },
+            0x95 => Packet::SpiBasicReply {
+                succeeded: reader.read_bool()?
+            },
+
+            0xa0 => Packet::JdacBasicRequest {
+                destination: reader.read_u8()?,
+                dacno: reader.read_u8()?,
+                reqno: reader.read_u8()?,
+                param: reader.read_u8()?,
+            },
+            0xa1 => Packet::JdacBasicReply {
+                succeeded: reader.read_bool()?,
+                retval: reader.read_u8()?
+            },
+
+            ty => return Err(Error::UnknownPacket(ty))
+        })
+    }
+
+    pub fn write_to<W>(&self, writer: &mut W) -> Result<(), IoError>
+        where W: Write + ?Sized
+    {
+
+        match *self {
+            Packet::EchoRequest =>
+                writer.write_u8(0x00)?,
+            Packet::EchoReply =>
+                writer.write_u8(0x01)?,
+            Packet::ResetRequest =>
+                writer.write_u8(0x02)?,
+            Packet::ResetAck =>
+                writer.write_u8(0x03)?,
+            Packet::TSCAck =>
+                writer.write_u8(0x04)?,
+
+            Packet::DestinationStatusRequest { destination } => {
+                writer.write_u8(0x20)?;
+                writer.write_u8(destination)?;
+            },
+            Packet::DestinationDownReply =>
+                writer.write_u8(0x21)?,
+            Packet::DestinationOkReply =>
+                writer.write_u8(0x22)?,
+            Packet::DestinationSequenceErrorReply { channel } => {
+                writer.write_u8(0x23)?;
+                writer.write_u16(channel)?;
+            },
+            Packet::DestinationCollisionReply { channel } => {
+                writer.write_u8(0x24)?;
+                writer.write_u16(channel)?;
+            },
+            Packet::DestinationBusyReply { channel } => {
+                writer.write_u8(0x25)?;
+                writer.write_u16(channel)?;
+            },
+
+            Packet::RoutingSetPath { destination, hops } => {
+                writer.write_u8(0x30)?;
+                writer.write_u8(destination)?;
+                writer.write_all(&hops)?;
+            },
+            Packet::RoutingSetRank { rank } => {
+                writer.write_u8(0x31)?;
+                writer.write_u8(rank)?;
+            },
+            Packet::RoutingAck =>
+                writer.write_u8(0x32)?,
+
+            Packet::MonitorRequest { destination, channel, probe } => {
+                writer.write_u8(0x40)?;
+                writer.write_u8(destination)?;
+                writer.write_u16(channel)?;
+                writer.write_u8(probe)?;
+            },
+            Packet::MonitorReply { value } => {
+                writer.write_u8(0x41)?;
+                writer.write_u32(value)?;
+            },
+            Packet::InjectionRequest { destination, channel, overrd, value } => {
+                writer.write_u8(0x50)?;
+                writer.write_u8(destination)?;
+                writer.write_u16(channel)?;
+                writer.write_u8(overrd)?;
+                writer.write_u8(value)?;
+            },
+            Packet::InjectionStatusRequest { destination, channel, overrd } => {
+                writer.write_u8(0x51)?;
+                writer.write_u8(destination)?;
+                writer.write_u16(channel)?;
+                writer.write_u8(overrd)?;
+            },
+            Packet::InjectionStatusReply { value } => {
+                writer.write_u8(0x52)?;
+                writer.write_u8(value)?;
+            },
+
+            Packet::I2cStartRequest { destination, busno } => {
+                writer.write_u8(0x80)?;
+                writer.write_u8(destination)?;
+                writer.write_u8(busno)?;
+            },
+            Packet::I2cRestartRequest { destination, busno } => {
+                writer.write_u8(0x81)?;
+                writer.write_u8(destination)?;
+                writer.write_u8(busno)?;
+            },
+            Packet::I2cStopRequest { destination, busno } => {
+                writer.write_u8(0x82)?;
+                writer.write_u8(destination)?;
+                writer.write_u8(busno)?;
+            },
+            Packet::I2cWriteRequest { destination, busno, data } => {
+                writer.write_u8(0x83)?;
+                writer.write_u8(destination)?;
+                writer.write_u8(busno)?;
+                writer.write_u8(data)?;
+            },
+            Packet::I2cWriteReply { succeeded, ack } => {
+                writer.write_u8(0x84)?;
+                writer.write_bool(succeeded)?;
+                writer.write_bool(ack)?;
+            },
+            Packet::I2cReadRequest { destination, busno, ack } => {
+                writer.write_u8(0x85)?;
+                writer.write_u8(destination)?;
+                writer.write_u8(busno)?;
+                writer.write_bool(ack)?;
+            },
+            Packet::I2cReadReply { succeeded, data } => {
+                writer.write_u8(0x86)?;
+                writer.write_bool(succeeded)?;
+                writer.write_u8(data)?;
+            },
+            Packet::I2cBasicReply { succeeded } => {
+                writer.write_u8(0x87)?;
+                writer.write_bool(succeeded)?;
+            },
+
+            Packet::SpiSetConfigRequest { destination, busno, flags, length, div, cs } => {
+                writer.write_u8(0x90)?;
+                writer.write_u8(destination)?;
+                writer.write_u8(busno)?;
+                writer.write_u8(flags)?;
+                writer.write_u8(length)?;
+                writer.write_u8(div)?;
+                writer.write_u8(cs)?;
+            },
+            Packet::SpiWriteRequest { destination, busno, data } => {
+                writer.write_u8(0x92)?;
+                writer.write_u8(destination)?;
+                writer.write_u8(busno)?;
+                writer.write_u32(data)?;
+            },
+            Packet::SpiReadRequest { destination, busno } => {
+                writer.write_u8(0x93)?;
+                writer.write_u8(destination)?;
+                writer.write_u8(busno)?;
+            },
+            Packet::SpiReadReply { succeeded, data } => {
+                writer.write_u8(0x94)?;
+                writer.write_bool(succeeded)?;
+                writer.write_u32(data)?;
+            },
+            Packet::SpiBasicReply { succeeded } => {
+                writer.write_u8(0x95)?;
+                writer.write_bool(succeeded)?;
+            },
+
+            Packet::JdacBasicRequest { destination, dacno, reqno, param } => {
+                writer.write_u8(0xa0)?;
+                writer.write_u8(destination)?;
+                writer.write_u8(dacno)?;
+                writer.write_u8(reqno)?;
+                writer.write_u8(param)?;
+            }
+            Packet::JdacBasicReply { succeeded, retval } => {
+                writer.write_u8(0xa1)?;
+                writer.write_bool(succeeded)?;
+                writer.write_u8(retval)?;
+            },
+        }
+        Ok(())
+    }
+    
+}

src/libboard_artiq/src/lib.rs

@@ -0,0 +1,69 @@
+#![no_std]
+#![feature(never_type)]
+
+extern crate log;
+extern crate crc;
+extern crate embedded_hal;
+extern crate core_io;
+extern crate io;
+extern crate libboard_zynq;
+extern crate libregister;
+extern crate libconfig;
+extern crate libcortex_a9;
+extern crate libasync;
+extern crate log_buffer;
+
+#[path = "../../../build/pl.rs"]
+pub mod pl;
+pub mod drtioaux_proto;
+pub mod drtio_routing;
+pub mod logger;
+#[cfg(has_si5324)]
+pub mod si5324;
+#[cfg(has_drtio)]
+pub mod drtioaux;
+#[cfg(has_drtio)]
+pub mod drtioaux_async;
+#[cfg(has_drtio)]
+#[path = "../../../build/mem.rs"]
+pub mod mem;
+
+use core::{cmp, str};
+use libboard_zynq::slcr;
+use libregister::RegisterW;
+
+pub fn identifier_read(buf: &mut [u8]) -> &str {
+    unsafe {
+        pl::csr::identifier::address_write(0);
+        let len = pl::csr::identifier::data_read();
+        let len = cmp::min(len, buf.len() as u8);
+        for i in 0..len {
+            pl::csr::identifier::address_write(1 + i);
+            buf[i as usize] = pl::csr::identifier::data_read();
+        }
+        str::from_utf8_unchecked(&buf[..len as usize])
+    }
+}
+
+pub fn init_gateware() {
+    // Set up PS->PL clocks
+    slcr::RegisterBlock::unlocked(|slcr| {
+        // As we are touching the mux, the clock may glitch, so reset the PL.
+        slcr.fpga_rst_ctrl.write(
+            slcr::FpgaRstCtrl::zeroed()
+                .fpga0_out_rst(true)
+                .fpga1_out_rst(true)
+                .fpga2_out_rst(true)
+                .fpga3_out_rst(true)
+        );
+        slcr.fpga0_clk_ctrl.write(
+            slcr::Fpga0ClkCtrl::zeroed()
+                .src_sel(slcr::PllSource::IoPll)
+                .divisor0(8)
+                .divisor1(1)
+        );
+        slcr.fpga_rst_ctrl.write(
+            slcr::FpgaRstCtrl::zeroed()
+        );
+    });
+}

src/libboard_artiq/src/si5324.rs

@@ -3,14 +3,14 @@ use log::info;
 use libboard_zynq::{i2c::I2c, timer::GlobalTimer, time::Milliseconds};
 use embedded_hal::blocking::delay::DelayUs;
 #[cfg(not(si5324_soft_reset))]
-use pl::csr;
+use crate::pl::csr;
 
 type Result<T> = result::Result<T, &'static str>;
 
 const ADDRESS: u8 = 0x68;
 
 #[cfg(not(si5324_soft_reset))]
-fn hard_reset(timer: GlobalTimer) {
+fn hard_reset(timer: &mut GlobalTimer) {
     unsafe { csr::si5324_rst_n::out_write(0); }
     timer.delay_us(1_000);
     unsafe { csr::si5324_rst_n::out_write(1); }
@@ -104,6 +104,7 @@ fn write(i2c: &mut I2c, reg: u8, val: u8) -> Result<()> {
     Ok(())
 }
 
+#[allow(dead_code)]
 fn write_no_ack_value(i2c: &mut I2c, reg: u8, val: u8) -> Result<()> {
     i2c.start().unwrap();
     if !i2c.write(ADDRESS << 1).unwrap() {
@@ -146,8 +147,9 @@ fn ident(i2c: &mut I2c) -> Result<u16> {
 }
 
 #[cfg(si5324_soft_reset)]
-fn soft_reset(i2c: &mut I2c, timer: GlobalTimer) -> Result<()> {
-    write_no_ack_value(i2c, 136, read(i2c, 136)? | 0x80)?;
+fn soft_reset(i2c: &mut I2c, timer: &mut GlobalTimer) -> Result<()> {
+    let val = read(i2c, 136)?;
+    write_no_ack_value(i2c, 136, val | 0x80)?;
     timer.delay_us(10_000);
     Ok(())
 }
@@ -167,7 +169,7 @@ fn locked(i2c: &mut I2c) -> Result<bool> {
     Ok((read(i2c, 130)? & 0x01) == 0)  // LOL_INT=0
 }
 
-fn monitor_lock(i2c: &mut I2c, timer: GlobalTimer) -> Result<()> {
+fn monitor_lock(i2c: &mut I2c, timer: &mut GlobalTimer) -> Result<()> {
     info!("waiting for Si5324 lock...");
     let timeout = timer.get_time() + Milliseconds(20_000);
     while !locked(i2c)? {
@@ -180,7 +182,7 @@ fn monitor_lock(i2c: &mut I2c, timer: GlobalTimer) -> Result<()> {
     Ok(())
 }
 
-fn init(i2c: &mut I2c, timer: GlobalTimer) -> Result<()> {
+fn init(i2c: &mut I2c, timer: &mut GlobalTimer) -> Result<()> {
     #[cfg(not(si5324_soft_reset))]
     hard_reset(timer);
 
@@ -189,6 +191,10 @@ fn init(i2c: &mut I2c, timer: GlobalTimer) -> Result<()> {
         i2c.pca9548_select(0x70, 0)?;
         i2c.pca9548_select(0x71, 1 << 3)?;
     }
+    #[cfg(feature = "target_zc706")]
+    {
+        i2c.pca9548_select(0x74, 1 << 4)?;
+    }
 
     if ident(i2c)? != 0x0182 {
         return Err("Si5324 does not have expected product number");
@@ -199,7 +205,7 @@ fn init(i2c: &mut I2c, timer: GlobalTimer) -> Result<()> {
     Ok(())
 }
 
-pub fn bypass(i2c: &mut I2c, input: Input, timer: GlobalTimer) -> Result<()> {
+pub fn bypass(i2c: &mut I2c, input: Input, timer: &mut GlobalTimer) -> Result<()> {
     let cksel_reg = match input {
         Input::Ckin1 => 0b00,
         Input::Ckin2 => 0b01,
@@ -213,7 +219,7 @@ pub fn bypass(i2c: &mut I2c, input: Input, timer: GlobalTimer) -> Result<()> {
     Ok(())
 }
 
-pub fn setup(i2c: &mut I2c, settings: &FrequencySettings, input: Input, timer: GlobalTimer) -> Result<()> {
+pub fn setup(i2c: &mut I2c, settings: &FrequencySettings, input: Input, timer: &mut GlobalTimer) -> Result<()> {
     let s = map_frequency_settings(settings)?;
     let cksel_reg = match input {
         Input::Ckin1 => 0b00,
@@ -259,7 +265,7 @@ pub fn setup(i2c: &mut I2c, settings: &FrequencySettings, input: Input, timer: G
     Ok(())
 }
 
-pub fn select_input(i2c: &mut I2c, input: Input, timer: GlobalTimer) -> Result<()> {
+pub fn select_input(i2c: &mut I2c, input: Input, timer: &mut GlobalTimer) -> Result<()> {
     let cksel_reg = match input {
         Input::Ckin1 => 0b00,
         Input::Ckin2 => 0b01,
@@ -271,3 +277,77 @@ pub fn select_input(i2c: &mut I2c, input: Input, timer: GlobalTimer) -> Result<(
     monitor_lock(i2c, timer)?;
     Ok(())
 }
+
+#[cfg(has_siphaser)]
+pub mod siphaser {
+    use super::*;
+    use crate::pl::csr;
+
+    pub fn select_recovered_clock(i2c: &mut I2c, rc: bool, timer: &mut GlobalTimer) -> Result<()> {
+        let val = read(i2c, 3)?;
+        write(i2c, 3,   (val & 0xdf) | (1 << 5))?;  // DHOLD=1
+        unsafe {
+            csr::siphaser::switch_clocks_write(if rc { 1 } else { 0 });
+        }
+        let val = read(i2c, 3)?;
+        write(i2c, 3,   (val & 0xdf) | (0 << 5))?;  // DHOLD=0
+        monitor_lock(i2c, timer)?;
+        Ok(())
+    }
+
+    fn phase_shift(direction: u8, timer: &mut GlobalTimer) {
+        unsafe {
+            csr::siphaser::phase_shift_write(direction);
+            while csr::siphaser::phase_shift_done_read() == 0 {}
+        }
+        // wait for the Si5324 loop to stabilize
+        timer.delay_us(500);
+    }
+
+    fn has_error(timer: &mut GlobalTimer) -> bool {
+        unsafe {
+            csr::siphaser::error_write(1);
+        }
+        timer.delay_us(5_000);
+        unsafe {
+            csr::siphaser::error_read() != 0
+        }
+    }
+
+    fn find_edge(target: bool, timer: &mut GlobalTimer) -> Result<u32> {
+        let mut nshifts = 0;
+
+        let mut previous = has_error(timer);
+        loop {
+            phase_shift(1, timer);
+            nshifts += 1;
+            let current = has_error(timer);
+            if previous != target && current == target {
+                return Ok(nshifts);
+            }
+            if nshifts > 5000 {
+                return Err("failed to find timing error edge");
+            }
+            previous = current;
+        }
+    }
+
+    pub fn calibrate_skew(timer: &mut GlobalTimer) -> Result<()> {
+        let jitter_margin = 32;
+        let lead = find_edge(false, timer)?;
+        for _ in 0..jitter_margin {
+            phase_shift(1, timer);
+        }
+        let width = find_edge(true, timer)? + jitter_margin;
+        // width is 360 degrees (one full rotation of the phase between s/h limits) minus jitter
+        info!("calibration successful, lead: {}, width: {} ({}deg)", lead, width, width*360/(56*8));
+
+        // Apply reverse phase shift for half the width to get into the
+        // middle of the working region.
+        for _ in 0..width/2 {
+            phase_shift(0, timer);
+        }
+
+        Ok(())
+    }
+}

src/libbuild_zynq/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+authors = ["M-Labs"]
+name = "build_zynq"
+version = "0.0.0"
+
+[lib]
+name = "build_zynq"
+path = "lib.rs"

src/libbuild_zynq/lib.rs

@@ -0,0 +1,13 @@
+use std::fs::File;
+use std::io::{BufRead, BufReader};
+
+pub fn cfg() {
+    // Handle rustc-cfg file
+    let cfg_path = "../../build/rustc-cfg";
+    println!("cargo:rerun-if-changed={}", cfg_path);
+
+    let f = BufReader::new(File::open(cfg_path).unwrap());
+    for line in f.lines() {
+        println!("cargo:rustc-cfg={}", line.unwrap());
+    }
+}

src/libio/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+authors = ["M-Labs"]
+name = "io"
+version = "0.0.0"
+
+[lib]
+name = "io"
+path = "lib.rs"
+
+[dependencies]
+core_io = { version = "0.1", features = ["collections"] }
+byteorder = { version = "1.0", default-features = false, optional = true }
+
+libsupport_zynq = { default-features = false, features = ["alloc_core"], git = "https://git.m-labs.hk/M-Labs/zynq-rs.git" }
+
+[features]
+alloc = []

src/libio/cursor.rs

@@ -0,0 +1,81 @@
+use core_io::{Read, Write, Error as IoError};
+
+#[derive(Debug, Clone)]
+pub struct Cursor<T> {
+    inner: T,
+    pos:   usize
+}
+
+impl<T> Cursor<T> {
+    #[inline]
+    pub fn new(inner: T) -> Cursor<T> {
+        Cursor { inner, pos: 0 }
+    }
+
+    #[inline]
+    pub fn into_inner(self) -> T {
+        self.inner
+    }
+
+    #[inline]
+    pub fn get_ref(&self) -> &T {
+        &self.inner
+    }
+
+    #[inline]
+    pub fn get_mut(&mut self) -> &mut T {
+        &mut self.inner
+    }
+
+    #[inline]
+    pub fn position(&self) -> usize {
+        self.pos
+    }
+
+    #[inline]
+    pub fn set_position(&mut self, pos: usize) {
+        self.pos = pos
+    }
+}
+
+impl<T: AsRef<[u8]>> Read for Cursor<T> {
+
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize, IoError> {
+        let data = &self.inner.as_ref()[self.pos..];
+        let len = buf.len().min(data.len());
+        buf[..len].copy_from_slice(&data[..len]);
+        self.pos += len;
+        Ok(len)
+    }
+}
+
+impl Write for Cursor<&mut [u8]> {
+
+    fn write(&mut self, buf: &[u8]) -> Result<usize, IoError> {
+        let data = &mut self.inner[self.pos..];
+        let len  = buf.len().min(data.len());
+        data[..len].copy_from_slice(&buf[..len]);
+        self.pos += len;
+        Ok(len)
+    }
+
+    #[inline]
+    fn flush(&mut self) -> Result<(), IoError> {
+        Ok(())
+    }
+}
+
+#[cfg(feature = "alloc")]
+impl Write for Cursor<::alloc::Vec<u8>> {
+
+    #[inline]
+    fn write(&mut self, buf: &[u8]) -> Result<usize, IoError> {
+        self.inner.extend_from_slice(buf);
+        Ok(buf.len())
+    }
+
+    #[inline]
+    fn flush(&mut self) -> Result<(), IoError> {
+        Ok(())
+    }
+}

src/libio/lib.rs

@@ -0,0 +1,22 @@
+#![no_std]
+#![feature(never_type)]
+#![cfg_attr(feature = "alloc", feature(alloc))]
+
+extern crate alloc;
+extern crate core_io;
+
+#[cfg(feature = "alloc")]
+#[macro_use]
+use alloc;
+#[cfg(feature = "byteorder")]
+extern crate byteorder;
+
+pub mod cursor;
+#[cfg(feature = "byteorder")]
+pub mod proto;
+
+pub use cursor::Cursor;
+#[cfg(feature = "byteorder")]
+pub use proto::{ProtoRead, ProtoWrite};
+#[cfg(all(feature = "byteorder", feature = "alloc"))]
+pub use proto::ReadStringError;

src/runtime/Cargo.toml

@@ -6,10 +6,13 @@ authors = ["M-Labs"]
 edition = "2018"
 
 [features]
-target_zc706 = ["libboard_zynq/target_zc706", "libsupport_zynq/target_zc706", "libconfig/target_zc706"]
-target_kasli_soc = ["libboard_zynq/target_kasli_soc", "libsupport_zynq/target_kasli_soc", "libconfig/target_kasli_soc"]
+target_zc706 = ["libboard_zynq/target_zc706", "libsupport_zynq/target_zc706", "libconfig/target_zc706", "libboard_artiq/target_zc706"]
+target_kasli_soc = ["libboard_zynq/target_kasli_soc", "libsupport_zynq/target_kasli_soc", "libconfig/target_kasli_soc", "libboard_artiq/target_kasli_soc"]
 default = ["target_zc706"]
 
+[build-dependencies]
+build_zynq = { path = "../libbuild_zynq" }
+
 [dependencies]
 num-traits = { version = "0.2", default-features = false }
 num-derive = "0.3"
@@ -37,3 +40,5 @@ dyld = { path = "../libdyld" }
 dwarf = { path = "../libdwarf" }
 unwind = { path = "../libunwind" }
 libc = { path = "../libc" }
+io = { path = "../libio" }
+libboard_artiq = { path = "../libboard_artiq" }

src/runtime/build.rs

@@ -1,9 +1,10 @@
 use std::env;
 use std::fs::File;
 use std::io::Write;
-use std::io::{BufRead, BufReader};
 use std::path::PathBuf;
 
+extern crate build_zynq;
+
 fn main() {
     // Put the linker script somewhere the linker can find it
     let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
@@ -16,13 +17,5 @@ fn main() {
     // Only re-run the build script when link.x is changed,
     // instead of when any part of the source code changes.
     println!("cargo:rerun-if-changed=link.x");
-
-    // Handle rustc-cfg file
-    let cfg_path = "../../build/rustc-cfg";
-    println!("cargo:rerun-if-changed={}", cfg_path);
-
-    let f = BufReader::new(File::open(cfg_path).unwrap());
-    for line in f.lines() {
-        println!("cargo:rustc-cfg={}", line.unwrap());
-    }
+    build_zynq::cfg();
 }

src/runtime/src/comms.rs

@@ -21,6 +21,7 @@ use libcortex_a9::{semaphore::Semaphore, mutex::Mutex, sync_channel::{Sender, Re
 use futures::{select_biased, future::FutureExt};
 use libasync::{smoltcp::{Sockets, TcpStream}, task};
 use libconfig::{Config, net_settings};
+use libboard_artiq::drtio_routing;
 
 use crate::proto_async::*;
 use crate::kernel;
@@ -28,7 +29,9 @@ use crate::rpc;
 use crate::moninj;
 use crate::mgmt;
 use crate::analyzer;
-
+use crate::rtio_mgt;
+#[cfg(has_drtio)]
+use crate::pl;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum Error {
@@ -387,8 +390,21 @@ pub fn main(timer: GlobalTimer, cfg: Config) {
 
     Sockets::init(32);
 
+    // before, mutex was on io, but now that io isn't used...?
+    let aux_mutex: Rc<Mutex<bool>> = Rc::new(Mutex::new(false));
+    #[cfg(has_drtio)]
+    let drtio_routing_table = Rc::new(RefCell::new(
+        drtio_routing::config_routing_table(pl::csr::DRTIO.len(), &cfg)));
+    #[cfg(not(has_drtio))]
+    let drtio_routing_table = Rc::new(RefCell::new(drtio_routing::RoutingTable::default_empty()));
+    let up_destinations = Rc::new(RefCell::new([false; drtio_routing::DEST_COUNT]));
+    #[cfg(has_drtio_routing)]
+    drtio_routing::interconnect_disable_all();
+
+    rtio_mgt::startup(&aux_mutex, &drtio_routing_table, &up_destinations, timer);
+
     analyzer::start();
-    moninj::start(timer);
+    moninj::start(timer, aux_mutex, drtio_routing_table);
 
     let control: Rc<RefCell<kernel::Control>> = Rc::new(RefCell::new(kernel::Control::start()));
     let idle_kernel = Rc::new(cfg.read("idle").ok());

src/runtime/src/main.rs

@@ -11,82 +11,43 @@
 
 extern crate alloc;
 
-use core::{cmp, str};
 use log::{info, warn, error};
 
-use libboard_zynq::{timer::GlobalTimer, mpcore, gic, slcr};
+use libboard_zynq::{timer::GlobalTimer, mpcore, gic};
 use libasync::{task, block_async};
 use libsupport_zynq::ram;
 use nb;
 use void::Void;
 use embedded_hal::blocking::delay::DelayMs;
 use libconfig::Config;
-use libregister::RegisterW;
 use libcortex_a9::l2c::enable_l2_cache;
+use libboard_artiq::{logger, identifier_read, init_gateware, pl};
+#[cfg(has_si5324)]
+use libboard_artiq::si5324;
 
-mod proto_core_io;
 mod proto_async;
 mod comms;
 mod rpc;
-#[path = "../../../build/pl.rs"]
-mod pl;
 #[cfg(ki_impl = "csr")]
 #[path = "rtio_csr.rs"]
 mod rtio;
 #[cfg(ki_impl = "acp")]
 #[path = "rtio_acp.rs"]
 mod rtio;
+mod rtio_mgt;
 mod kernel;
 mod moninj;
 mod eh_artiq;
 mod panic;
-mod logger;
 mod mgmt;
 mod analyzer;
 mod irq;
 mod i2c;
-#[cfg(has_si5324)]
-mod si5324;
 
-fn init_gateware() {
-    // Set up PS->PL clocks
-    slcr::RegisterBlock::unlocked(|slcr| {
-        // As we are touching the mux, the clock may glitch, so reset the PL.
-        slcr.fpga_rst_ctrl.write(
-            slcr::FpgaRstCtrl::zeroed()
-                .fpga0_out_rst(true)
-                .fpga1_out_rst(true)
-                .fpga2_out_rst(true)
-                .fpga3_out_rst(true)
-        );
-        slcr.fpga0_clk_ctrl.write(
-            slcr::Fpga0ClkCtrl::zeroed()
-                .src_sel(slcr::PllSource::IoPll)
-                .divisor0(8)
-                .divisor1(1)
-        );
-        slcr.fpga_rst_ctrl.write(
-            slcr::FpgaRstCtrl::zeroed()
-        );
-    });
-}
-
-fn identifier_read(buf: &mut [u8]) -> &str {
-    unsafe {
-        pl::csr::identifier::address_write(0);
-        let len = pl::csr::identifier::data_read();
-        let len = cmp::min(len, buf.len() as u8);
-        for i in 0..len {
-            pl::csr::identifier::address_write(1 + i);
-            buf[i as usize] = pl::csr::identifier::data_read();
-        }
-        str::from_utf8_unchecked(&buf[..len as usize])
-    }
-}
-
-fn init_rtio(timer: &mut GlobalTimer, cfg: &Config) {
+fn init_rtio(timer: &mut GlobalTimer, _cfg: &Config) {
+    #[cfg(has_rtio_crg_clock_sel)]
     let clock_sel =
-        if let Ok(rtioclk) = cfg.read_str("rtioclk") {
+        if let Ok(rtioclk) = _cfg.read_str("rtioclk") {
             match rtioclk.as_ref() {
                 "internal" => {
                     info!("using internal RTIO clock");
@@ -130,6 +91,19 @@ fn init_rtio(timer: &mut GlobalTimer, cfg: &Config) {
     }
 }
 
+#[cfg(has_drtio)]
+fn init_drtio(timer: &mut GlobalTimer)
+{
+    unsafe {
+        pl::csr::drtio_transceiver::stable_clkin_write(1);
+    }
+    timer.delay_ms(2); // wait for CPLL/QPLL lock
+    unsafe {
+        pl::csr::drtio_transceiver::txenable_write(0xffffffffu32 as _);
+    }
+}
+
+
 fn wait_for_async_rtio_error() -> nb::Result<(), Void> {
     unsafe {
         if pl::csr::rtio_core::async_error_read() != 0 {
@@ -201,7 +175,7 @@ pub fn main_core0() {
     i2c::init();
     #[cfg(has_si5324)]
     si5324::setup(unsafe { (&mut i2c::I2C_BUS).as_mut().unwrap() },
-        &SI5324_SETTINGS, si5324::Input::Ckin2, timer).expect("cannot initialize Si5324");
+        &SI5324_SETTINGS, si5324::Input::Ckin2, &mut timer).expect("cannot initialize Si5324");
 
     let cfg = match Config::new() {
         Ok(cfg) => cfg,
@@ -211,6 +185,9 @@ pub fn main_core0() {
         }
     };
 
+    #[cfg(has_drtio)]
+    init_drtio(&mut timer);
+
     init_rtio(&mut timer, &cfg);
     task::spawn(report_async_rtio_errors());
 

src/runtime/src/mgmt.rs

@@ -6,7 +6,7 @@ use core::cell::RefCell;
 use alloc::{rc::Rc, vec::Vec, string::String};
 use log::{self, info, debug, warn, error, LevelFilter};
 
-use crate::logger::{BufferLogger, LogBufferRef};
+use libboard_artiq::logger::{BufferLogger, LogBufferRef};
 use crate::proto_async::*;
 use num_derive::FromPrimitive;
 use num_traits::FromPrimitive;

src/runtime/src/moninj.rs

@@ -1,17 +1,19 @@
-use core::fmt;
-use alloc::collections::BTreeMap;
+use core::{fmt, cell::RefCell};
+use alloc::{collections::BTreeMap, rc::Rc};
 use log::{debug, info, warn};
 use void::Void;
 
+use libboard_artiq::drtio_routing;
+
 use libboard_zynq::{smoltcp, timer::GlobalTimer, time::Milliseconds};
 use libasync::{task, smoltcp::TcpStream, block_async, nb};
+use libcortex_a9::mutex::Mutex;
 
 use num_derive::{FromPrimitive, ToPrimitive};
 use num_traits::{FromPrimitive, ToPrimitive};
 use futures::{pin_mut, select_biased, FutureExt};
 
 use crate::proto_async::*;
-use crate::pl::csr;
 
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
@@ -19,7 +21,6 @@ pub enum Error {
     NetworkError(smoltcp::Error),
     UnexpectedPattern,
     UnrecognizedPacket,
-
 }
 
 pub type Result<T> = core::result::Result<T, Error>;
@@ -54,32 +55,109 @@ enum DeviceMessage {
     InjectionStatus = 1
 }
 
-fn read_probe(channel: i32, probe: i8) -> i32 {
+#[cfg(has_drtio)]
+mod remote_moninj {
+    use super::*;
+    use libboard_artiq::drtioaux;
+    use crate::rtio_mgt::drtio;
+    use log::error;
+
+    pub fn read_probe(aux_mutex: &Rc<Mutex<bool>>, timer: GlobalTimer, linkno: u8, destination: u8, channel: i32, probe: i8) -> i32 {
+        let reply = task::block_on(drtio::aux_transact(aux_mutex, linkno, &drtioaux::Packet::MonitorRequest { 
+            destination: destination,
+            channel: channel as _,
+            probe: probe as _},
+            timer));
+        match reply {
+            Ok(drtioaux::Packet::MonitorReply { value }) => return value as i32,
+            Ok(packet) => error!("received unexpected aux packet: {:?}", packet),
+            Err(e) => error!("aux packet error ({})", e)
+        }
+        0
+    }
+
+    pub fn inject(aux_mutex: &Rc<Mutex<bool>>, _timer: GlobalTimer, linkno: u8, destination: u8, channel: i32, overrd: i8, value: i8) {
+        let _lock = aux_mutex.lock();
+        drtioaux::send(linkno, &drtioaux::Packet::InjectionRequest {
+            destination: destination,
+            channel: channel as _,
+            overrd: overrd as _,
+            value: value as _
+        }).unwrap();
+    }
+
+    pub fn read_injection_status(aux_mutex: &Rc<Mutex<bool>>, timer: GlobalTimer, linkno: u8, destination: u8, channel: i32, overrd: i8) -> i8 {
+        let reply = task::block_on(drtio::aux_transact(aux_mutex, 
+            linkno, 
+            &drtioaux::Packet::InjectionStatusRequest {
+                destination: destination,
+                channel: channel as _,
+                overrd: overrd as _},
+            timer));
+        match reply {
+            Ok(drtioaux::Packet::InjectionStatusReply { value }) => return value as i8,
+            Ok(packet) => error!("received unexpected aux packet: {:?}", packet),
+            Err(e) => error!("aux packet error ({})", e)
+        }
+        0
+    }
+}
+
+mod local_moninj {
+    use libboard_artiq::pl::csr;
+
+    pub fn read_probe(channel: i32, probe: i8) -> i32 {
         unsafe {
             csr::rtio_moninj::mon_chan_sel_write(channel as _);
             csr::rtio_moninj::mon_probe_sel_write(probe as _);
             csr::rtio_moninj::mon_value_update_write(1);
             csr::rtio_moninj::mon_value_read() as i32
         }
-}
+    }
 
-fn inject(channel: i32, overrd: i8, value: i8) {
+    pub fn inject(channel: i32, overrd: i8, value: i8) {
         unsafe {
             csr::rtio_moninj::inj_chan_sel_write(channel as _);
             csr::rtio_moninj::inj_override_sel_write(overrd as _);
             csr::rtio_moninj::inj_value_write(value as _);
         }
-}
+    }
 
-fn read_injection_status(channel: i32, overrd: i8) -> i8 {
+    pub fn read_injection_status(channel: i32, overrd: i8) -> i8 {
         unsafe {
             csr::rtio_moninj::inj_chan_sel_write(channel as _);
             csr::rtio_moninj::inj_override_sel_write(overrd as _);
             csr::rtio_moninj::inj_value_read() as i8
         }
+    }
 }
 
-async fn handle_connection(stream: &TcpStream, timer: GlobalTimer) -> Result<()> {
+#[cfg(has_drtio)]
+macro_rules! dispatch {
+    ($timer:ident, $aux_mutex:ident, $routing_table:ident, $channel:expr, $func:ident $(, $param:expr)*) => {{
+        let destination = ($channel >> 16) as u8;
+        let channel = $channel;
+        let routing_table = $routing_table.borrow_mut();
+        let hop = routing_table.0[destination as usize][0];
+        if hop == 0 {
+            local_moninj::$func(channel.into(), $($param, )*)
+        } else {
+            let linkno = hop - 1 as u8;
+            remote_moninj::$func($aux_mutex, $timer, linkno, destination, channel, $($param, )*)
+        }
+    }}
+}
+
+#[cfg(not(has_drtio))]
+macro_rules! dispatch {
+    ($timer:ident, $aux_mutex:ident, $routing_table:ident, $channel:expr, $func:ident $(, $param:expr)*) => {{
+        let channel = $channel as u16;
+        local_moninj::$func(channel.into(), $($param, )*)
+    }}
+}
+
+async fn handle_connection(stream: &TcpStream, timer: GlobalTimer, 
+        _aux_mutex: &Rc<Mutex<bool>>, _routing_table: &Rc<RefCell<drtio_routing::RoutingTable>>) -> Result<()> {
     if !expect(&stream, b"ARTIQ moninj\n").await? {
         return Err(Error::UnexpectedPattern);
     }
@@ -135,13 +213,13 @@ async fn handle_connection(stream: &TcpStream, timer: GlobalTimer) -> Result<()>
                         let channel = read_i32(&stream).await?;
                         let overrd = read_i8(&stream).await?;
                         let value = read_i8(&stream).await?;
-                        inject(channel, overrd, value);
+                        dispatch!(timer, _aux_mutex, _routing_table, channel, inject, overrd, value);
                         debug!("INJECT channel {}, overrd {}, value {}", channel, overrd, value);
                     },
                     HostMessage::GetInjectionStatus => {
                         let channel = read_i32(&stream).await?;
                         let overrd = read_i8(&stream).await?;
-                        let value = read_injection_status(channel, overrd);
+                        let value = dispatch!(timer, _aux_mutex, _routing_table, channel, read_injection_status, overrd);
                         write_i8(&stream, DeviceMessage::InjectionStatus.to_i8().unwrap()).await?;
                         write_i32(&stream, channel).await?;
                         write_i8(&stream, overrd).await?;
@@ -151,7 +229,7 @@ async fn handle_connection(stream: &TcpStream, timer: GlobalTimer) -> Result<()>
             },
             _ = timeout_f => {
                 for (&(channel, probe), previous) in probe_watch_list.iter_mut() {
-                    let current = read_probe(channel, probe);
+                    let current = dispatch!(timer, _aux_mutex, _routing_table, channel, read_probe, probe);
                     if previous.is_none() || previous.unwrap() != current {
                         write_i8(&stream, DeviceMessage::MonitorStatus.to_i8().unwrap()).await?;
                         write_i32(&stream, channel).await?;
@@ -161,7 +239,7 @@ async fn handle_connection(stream: &TcpStream, timer: GlobalTimer) -> Result<()>
                     }
                 }
                 for (&(channel, overrd), previous) in inject_watch_list.iter_mut() {
-                    let current = read_injection_status(channel, overrd);
+                    let current = dispatch!(timer, _aux_mutex, _routing_table, channel, read_injection_status, overrd);
                     if previous.is_none() || previous.unwrap() != current {
                         write_i8(&stream, DeviceMessage::InjectionStatus.to_i8().unwrap()).await?;
                         write_i32(&stream, channel).await?;
@@ -176,13 +254,15 @@ async fn handle_connection(stream: &TcpStream, timer: GlobalTimer) -> Result<()>
     }
 }
 
-pub fn start(timer: GlobalTimer) {
+pub fn start(timer: GlobalTimer, aux_mutex: Rc<Mutex<bool>>, routing_table: Rc<RefCell<drtio_routing::RoutingTable>>) {
     task::spawn(async move {
         loop {
+            let aux_mutex = aux_mutex.clone();
+            let routing_table = routing_table.clone();
             let stream = TcpStream::accept(1383, 2048, 2048).await.unwrap();
             task::spawn(async move {
                 info!("received connection");
-                let result = handle_connection(&stream, timer).await;
+                let result = handle_connection(&stream, timer, &aux_mutex, &routing_table).await;
                 match result {
                     Err(Error::NetworkError(smoltcp::Error::Finished)) => info!("peer closed connection"),
                     Err(error) => warn!("connection terminated: {}", error),

src/runtime/src/rpc.rs

@@ -10,7 +10,7 @@ use libasync::smoltcp::TcpStream;
 use alloc::boxed::Box;
 use async_recursion::async_recursion;
 
-use crate::proto_core_io::ProtoWrite;
+use io::proto::ProtoWrite;
 use crate::proto_async;
 use self::tag::{Tag, TagIterator, split_tag};
 

src/runtime/src/rtio_mgt.rs

@@ -0,0 +1,352 @@
+use core::cell::RefCell;
+use alloc::rc::Rc;
+use libboard_zynq::timer::GlobalTimer;
+use libboard_artiq::{pl::csr, drtio_routing};
+use libcortex_a9::mutex::Mutex;
+
+
+#[cfg(has_drtio)]
+pub mod drtio {
+    use super::*;
+    use libboard_artiq::drtioaux_async;
+    use libboard_artiq::drtioaux_async::Packet;
+    use libboard_artiq::drtioaux::Error;
+    use log::{warn, error, info};
+    use embedded_hal::blocking::delay::DelayMs;
+    use libasync::{task, delay};
+    use libboard_zynq::time::Milliseconds;
+
+    pub fn startup(aux_mutex: &Rc<Mutex<bool>>,
+            routing_table: &Rc<RefCell<drtio_routing::RoutingTable>>,
+            up_destinations: &Rc<RefCell<[bool; drtio_routing::DEST_COUNT]>>,
+            timer: GlobalTimer) {
+        let aux_mutex = aux_mutex.clone();
+        let routing_table = routing_table.clone();
+        let up_destinations = up_destinations.clone();
+        task::spawn(async move {
+            let routing_table = routing_table.borrow();
+            link_task(&aux_mutex, &routing_table, &up_destinations, timer).await;
+        });
+    }
+
+    async fn link_rx_up(linkno: u8) -> bool {
+        let linkno = linkno as usize;
+        unsafe {
+            (csr::DRTIO[linkno].rx_up_read)() == 1
+        }
+    }
+
+    async fn recv_aux_timeout(linkno: u8, timeout: u64, timer: GlobalTimer) -> Result<Packet, &'static str> {
+        if !link_rx_up(linkno).await {
+            return Err("link went down");
+        }
+        match drtioaux_async::recv_timeout(linkno, Some(timeout), timer).await {
+            Ok(packet) => return Ok(packet),
+            Err(Error::TimedOut) => return Err("timed out"),
+            Err(_) => return Err("aux packet error"),
+        }
+    }
+
+    pub async fn aux_transact(aux_mutex: &Mutex<bool>, linkno: u8, request: &Packet,
+            timer: GlobalTimer) -> Result<Packet, &'static str> {
+        let _lock = aux_mutex.lock();
+        drtioaux_async::send(linkno, request).await.unwrap();
+        recv_aux_timeout(linkno, 200, timer).await
+    }
+
+    async fn drain_buffer(linkno: u8, draining_time: Milliseconds, timer: GlobalTimer) {
+        let max_time = timer.get_time() + draining_time;
+        loop {
+            if timer.get_time() > max_time {
+                return;
+            } //could this be cut short?
+            let _ = drtioaux_async::recv(linkno).await;
+        }
+    }
+
+    async fn ping_remote(aux_mutex: &Rc<Mutex<bool>>, linkno: u8, timer: GlobalTimer) -> u32 {
+        let mut count = 0;
+        loop {
+            if !link_rx_up(linkno).await {
+                return 0
+            }
+            count += 1;
+            if count > 100 {
+                return 0;
+            }
+            let reply = aux_transact(aux_mutex, linkno, &Packet::EchoRequest, timer).await;
+            match reply {
+                Ok(Packet::EchoReply) => {
+                    // make sure receive buffer is drained
+                    let draining_time = Milliseconds(200);
+                    drain_buffer(linkno, draining_time, timer).await;
+                    return count;
+                }
+                _ => {}
+            }
+        }
+    }
+
+    async fn sync_tsc(aux_mutex: &Rc<Mutex<bool>>, linkno: u8, timer: GlobalTimer) -> Result<(), &'static str> {
+        let _lock = aux_mutex.lock();
+
+        unsafe {
+            (csr::DRTIO[linkno as usize].set_time_write)(1);
+            while (csr::DRTIO[linkno as usize].set_time_read)() == 1 {}
+        }
+        // TSCAck is the only aux packet that is sent spontaneously
+        // by the satellite, in response to a TSC set on the RT link.
+        let reply = recv_aux_timeout(linkno, 10000, timer).await?;
+        if reply == Packet::TSCAck {
+            return Ok(());
+        } else {
+            return Err("unexpected reply");
+        }
+    }
+
+    async fn load_routing_table(aux_mutex: &Rc<Mutex<bool>>, linkno: u8, routing_table: &drtio_routing::RoutingTable,
+        timer: GlobalTimer) -> Result<(), &'static str> {
+        for i in 0..drtio_routing::DEST_COUNT {
+            let reply = aux_transact(aux_mutex, linkno, &Packet::RoutingSetPath {
+                destination: i as u8,
+                hops: routing_table.0[i]
+            }, timer).await?;
+            if reply != Packet::RoutingAck {
+                return Err("unexpected reply");
+            }
+        }
+        Ok(())
+    }
+
+    async fn set_rank(aux_mutex: &Rc<Mutex<bool>>, linkno: u8, rank: u8, timer: GlobalTimer) -> Result<(), &'static str> {
+        let reply = aux_transact(aux_mutex, linkno, &Packet::RoutingSetRank {
+            rank: rank
+        }, timer).await?;
+        if reply != Packet::RoutingAck {
+            return Err("unexpected reply");
+        }
+        Ok(())
+    }
+
+    async fn init_buffer_space(destination: u8, linkno: u8) {
+        let linkno = linkno as usize;
+        unsafe {
+            (csr::DRTIO[linkno].destination_write)(destination);
+            (csr::DRTIO[linkno].force_destination_write)(1);
+            (csr::DRTIO[linkno].o_get_buffer_space_write)(1);
+            while (csr::DRTIO[linkno].o_wait_read)() == 1 {}
+            info!("[DEST#{}] buffer space is {}",
+                destination, (csr::DRTIO[linkno].o_dbg_buffer_space_read)());
+            (csr::DRTIO[linkno].force_destination_write)(0);
+        }
+    }
+
+    async fn process_unsolicited_aux(aux_mutex: &Rc<Mutex<bool>>, linkno: u8) {
+        let _lock = aux_mutex.lock();
+        match drtioaux_async::recv(linkno).await {
+            Ok(Some(packet)) => warn!("[LINK#{}] unsolicited aux packet: {:?}", linkno, packet),
+            Ok(None) => (),
+            Err(_) => warn!("[LINK#{}] aux packet error", linkno)
+        }
+    }
+
+    async fn process_local_errors(linkno: u8) {
+        let errors;
+        let linkidx = linkno as usize;
+        unsafe {
+            errors = (csr::DRTIO[linkidx].protocol_error_read)();
+            (csr::DRTIO[linkidx].protocol_error_write)(errors);
+        }
+        if errors != 0 {
+            error!("[LINK#{}] error(s) found (0x{:02x}):", linkno, errors);
+            if errors & 1 != 0 {
+                error!("[LINK#{}] received packet of an unknown type", linkno);
+            }
+            if errors & 2 != 0 {
+                error!("[LINK#{}] received truncated packet", linkno);
+            }
+            if errors & 4 != 0 {
+                error!("[LINK#{}] timeout attempting to get remote buffer space", linkno);
+            }
+        }
+    }
+
+    async fn destination_set_up(routing_table: &drtio_routing::RoutingTable,
+            up_destinations: &Rc<RefCell<[bool; drtio_routing::DEST_COUNT]>>,
+            destination: u8, up: bool) {
+        let mut up_destinations = up_destinations.borrow_mut();
+        up_destinations[destination as usize] = up;
+        if up {
+            drtio_routing::interconnect_enable(routing_table, 0, destination);
+            info!("[DEST#{}] destination is up", destination);
+        } else {
+            drtio_routing::interconnect_disable(destination);
+            info!("[DEST#{}] destination is down", destination);
+        }
+    }
+
+    async fn destination_up(up_destinations: &Rc<RefCell<[bool; drtio_routing::DEST_COUNT]>>, destination: u8) -> bool {
+        let up_destinations = up_destinations.borrow();
+        up_destinations[destination as usize]
+    }
+
+    async fn destination_survey(aux_mutex: &Rc<Mutex<bool>>, routing_table: &drtio_routing::RoutingTable,
+            up_links: &[bool],
+            up_destinations: &Rc<RefCell<[bool; drtio_routing::DEST_COUNT]>>,
+            timer: GlobalTimer) {
+        for destination in 0..drtio_routing::DEST_COUNT {
+            let hop = routing_table.0[destination][0];
+            let destination = destination as u8;
+
+            if hop == 0 {
+                /* local RTIO */
+                if !destination_up(up_destinations, destination).await {
+                    destination_set_up(routing_table, up_destinations, destination, true).await;
+                }
+            } else if hop as usize <= csr::DRTIO.len() {
+                let linkno = hop - 1;
+                if destination_up(up_destinations, destination).await {
+                    if up_links[linkno as usize] {
+                        let reply = aux_transact(aux_mutex, linkno, &Packet::DestinationStatusRequest {
+                            destination: destination
+                        }, timer).await;
+                        match reply {
+                            Ok(Packet::DestinationDownReply) =>
+                                destination_set_up(routing_table, up_destinations, destination, false).await,
+                            Ok(Packet::DestinationOkReply) => (),
+                            Ok(Packet::DestinationSequenceErrorReply { channel }) =>
+                                error!("[DEST#{}] RTIO sequence error involving channel 0x{:04x}", destination, channel),
+                            Ok(Packet::DestinationCollisionReply { channel }) =>
+                                error!("[DEST#{}] RTIO collision involving channel 0x{:04x}", destination, channel),
+                            Ok(Packet::DestinationBusyReply { channel }) =>
+                                error!("[DEST#{}] RTIO busy error involving channel 0x{:04x}", destination, channel),
+                            Ok(packet) => error!("[DEST#{}] received unexpected aux packet: {:?}", destination, packet),
+                            Err(e) => error!("[DEST#{}] communication failed ({})", destination, e)
+                        }
+                    } else {
+                        destination_set_up(routing_table, up_destinations, destination, false).await;
+                    }
+                } else {
+                    if up_links[linkno as usize] {
+                        let reply = aux_transact(aux_mutex, linkno, &Packet::DestinationStatusRequest {
+                            destination: destination
+                        }, timer).await;
+                        match reply {
+                            Ok(Packet::DestinationDownReply) => (),
+                            Ok(Packet::DestinationOkReply) => {
+                                destination_set_up(routing_table, up_destinations, destination, true).await;
+                                init_buffer_space(destination as u8, linkno).await;
+                            },
+                            Ok(packet) => error!("[DEST#{}] received unexpected aux packet: {:?}", destination, packet),
+                            Err(e) => error!("[DEST#{}] communication failed ({})", destination, e)
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    pub async fn link_task(aux_mutex: &Rc<Mutex<bool>>,
+            routing_table: &drtio_routing::RoutingTable,
+            up_destinations: &Rc<RefCell<[bool; drtio_routing::DEST_COUNT]>>,
+            timer: GlobalTimer) {
+        let mut up_links = [false; csr::DRTIO.len()];
+        loop {
+            for linkno in 0..csr::DRTIO.len() {
+                let linkno = linkno as u8;
+                if up_links[linkno as usize] {
+                    /* link was previously up */
+                    if link_rx_up(linkno).await {
+                        process_unsolicited_aux(aux_mutex, linkno).await;
+                        process_local_errors(linkno).await;
+                    } else {
+                        info!("[LINK#{}] link is down", linkno);
+                        up_links[linkno as usize] = false;
+                    }
+                } else {
+                    /* link was previously down */
+                    if link_rx_up(linkno).await {
+                        info!("[LINK#{}] link RX became up, pinging", linkno);
+                        let ping_count = ping_remote(aux_mutex, linkno, timer).await;
+                        if ping_count > 0 {
+                            info!("[LINK#{}] remote replied after {} packets", linkno, ping_count);
+                            up_links[linkno as usize] = true;
+                            if let Err(e) = sync_tsc(aux_mutex, linkno, timer).await {
+                                error!("[LINK#{}] failed to sync TSC ({})", linkno, e);
+                            }
+                            if let Err(e) = load_routing_table(aux_mutex, linkno, routing_table, timer).await {
+                                error!("[LINK#{}] failed to load routing table ({})", linkno, e);
+                            }
+                            if let Err(e) = set_rank(aux_mutex, linkno, 1 as u8, timer).await {
+                                error!("[LINK#{}] failed to set rank ({})", linkno, e);
+                            }
+                            info!("[LINK#{}] link initialization completed", linkno);
+                        } else {
+                            error!("[LINK#{}] ping failed", linkno);
+                        }
+                    }
+                }
+            }
+            destination_survey(aux_mutex, routing_table, &up_links, up_destinations, timer).await;
+            let mut countdown = timer.countdown();
+            delay(&mut countdown, Milliseconds(200)).await;
+        }
+    }
+
+    #[allow(dead_code)]
+    pub fn reset(aux_mutex: Rc<Mutex<bool>>, mut timer: GlobalTimer) {
+        for linkno in 0..csr::DRTIO.len() {
+            unsafe {
+                (csr::DRTIO[linkno].reset_write)(1);
+            }
+        }
+        timer.delay_ms(1);
+        for linkno in 0..csr::DRTIO.len() {
+            unsafe {
+                (csr::DRTIO[linkno].reset_write)(0);
+            }
+        }
+
+        for linkno in 0..csr::DRTIO.len() {
+            let linkno = linkno as u8;
+            if task::block_on(link_rx_up(linkno)) {
+                let reply = task::block_on(aux_transact(&aux_mutex, linkno,
+                    &Packet::ResetRequest, timer));
+                match reply {
+                    Ok(Packet::ResetAck) => (),
+                    Ok(_) => error!("[LINK#{}] reset failed, received unexpected aux packet", linkno),
+                    Err(e) => error!("[LINK#{}] reset failed, aux packet error ({})", linkno, e)
+                }
+            }
+        }
+    }
+}
+
+#[cfg(not(has_drtio))]
+pub mod drtio {
+    use super::*;
+
+    pub fn startup(_aux_mutex: &Rc<Mutex<bool>>, _routing_table: &Rc<RefCell<drtio_routing::RoutingTable>>,
+        _up_destinations: &Rc<RefCell<[bool; drtio_routing::DEST_COUNT]>>, _timer: GlobalTimer) {}
+    
+    #[allow(dead_code)]
+    pub fn reset(_aux_mutex: Rc<Mutex<bool>>, mut _timer: GlobalTimer) {}
+}
+
+pub fn startup(aux_mutex: &Rc<Mutex<bool>>,
+        routing_table: &Rc<RefCell<drtio_routing::RoutingTable>>,
+        up_destinations: &Rc<RefCell<[bool; drtio_routing::DEST_COUNT]>>, 
+        timer: GlobalTimer) {
+    drtio::startup(aux_mutex, routing_table, up_destinations, timer);
+    unsafe {
+        csr::rtio_core::reset_phy_write(1);
+    }
+}
+
+#[allow(dead_code)]
+pub fn reset(aux_mutex: Rc<Mutex<bool>>, timer: GlobalTimer) {
+    unsafe {
+        csr::rtio_core::reset_write(1);
+    }
+    drtio::reset(aux_mutex, timer)
+}