add RTIO syscalls

Cargo.lock

@@ -30,6 +30,12 @@ version = "0.1.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "036b035e9ebcd705affece16319223d19f229e2358be6e3b7b094e57193312e6"
 
+[[package]]
+name = "cslice"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0f8cb7306107e4b10e64994de6d3274bd08996a7c1322a27b86482392f96be0a"
+
 [[package]]
 name = "dyld"
 version = "0.1.0"
@@ -154,6 +160,7 @@ checksum = "bd7a31eed1591dcbc95d92ad7161908e72f4677f8fabf2a32ca49b4237cbf211"
 name = "runtime"
 version = "0.1.0"
 dependencies = [
+ "cslice",
  "dyld",
  "libasync",
  "libboard_zynq",

runtime/Cargo.toml

@@ -12,6 +12,7 @@ default = ["target_zc706"]
 [dependencies]
 num-traits = { version = "0.2", default-features = false }
 num-derive = "0.3"
+cslice = "0.3"
 libboard_zynq = { git = "https://git.m-labs.hk/M-Labs/zc706.git" }
 libsupport_zynq = { git = "https://git.m-labs.hk/M-Labs/zc706.git" }
 libasync = { git = "https://git.m-labs.hk/M-Labs/zc706.git" }

runtime/src/main.rs

@@ -13,6 +13,7 @@ use libsupport_zynq::ram;
 
 
 mod pl;
+mod rtio;
 mod network;
 
 fn identifier_read(buf: &mut [u8]) -> &str {

runtime/src/rtio.rs

@@ -0,0 +1,173 @@
+use core::ptr::{read_volatile, write_volatile};
+use cslice::CSlice;
+
+use libboard_zynq::println;
+
+use crate::pl::csr;
+
+pub const RTIO_O_STATUS_WAIT:                      u8 = 1;
+pub const RTIO_O_STATUS_UNDERFLOW:                 u8 = 2;
+pub const RTIO_O_STATUS_DESTINATION_UNREACHABLE:   u8 = 4;
+pub const RTIO_I_STATUS_WAIT_EVENT:                u8 = 1;
+pub const RTIO_I_STATUS_OVERFLOW:                  u8 = 2;
+pub const RTIO_I_STATUS_WAIT_STATUS:               u8 = 4;
+pub const RTIO_I_STATUS_DESTINATION_UNREACHABLE:   u8 = 8;
+
+#[repr(C)]
+pub struct TimestampedData {
+    timestamp: i64,
+    data: i32,
+}
+
+pub extern fn init() {
+    // TODO
+}
+
+pub extern fn get_destination_status(destination: i32) -> bool {
+    // TODO
+    destination == 0
+}
+
+pub extern fn get_counter() -> i64 {
+    unsafe {
+        csr::rtio::counter_update_write(1);
+        csr::rtio::counter_read() as i64
+    }
+}
+
+// writing the LSB of o_data (offset=0) triggers the RTIO write
+#[inline(always)]
+pub unsafe fn rtio_o_data_write(offset: usize, data: u32) {
+    write_volatile(
+        csr::rtio::O_DATA_ADDR.offset((csr::rtio::O_DATA_SIZE - 1 - offset) as isize),
+        data);
+}
+
+#[inline(always)]
+pub unsafe fn rtio_i_data_read(offset: usize) -> u32 {
+    read_volatile(
+        csr::rtio::I_DATA_ADDR.offset((csr::rtio::I_DATA_SIZE - 1 - offset) as isize))
+}
+
+#[inline(never)]
+unsafe fn process_exceptional_status(channel: i32, status: u8) {
+    let timestamp = *(csr::rtio::NOW_HI_ADDR as *const i64);
+    if status & RTIO_O_STATUS_WAIT != 0 {
+        while csr::rtio::o_status_read() & RTIO_O_STATUS_WAIT != 0 {}
+    }
+    if status & RTIO_O_STATUS_UNDERFLOW != 0 {
+        println!("RTIO underflow at {0} mu, channel {1}, slack {2} mu",
+            timestamp, channel as i64, timestamp - get_counter());
+    }
+    if status & RTIO_O_STATUS_DESTINATION_UNREACHABLE != 0 {
+        println!("RTIO destination unreachable, output, at {0} mu, channel {1}",
+            timestamp, channel as i64);
+    }
+}
+
+pub extern fn output(target: i32, data: i32) {
+    unsafe {
+        csr::rtio::target_write(target as u32);
+        // writing target clears o_data
+        rtio_o_data_write(0, data as _);
+        let status = csr::rtio::o_status_read();
+        if status != 0 {
+            process_exceptional_status(target >> 8, status);
+        }
+    }
+}
+
+pub extern fn output_wide(target: i32, data: CSlice<i32>) {
+    unsafe {
+        csr::rtio::target_write(target as u32);
+        // writing target clears o_data
+        for i in (0..data.len()).rev() {
+            rtio_o_data_write(i, data[i] as _)
+        }
+        let status = csr::rtio::o_status_read();
+        if status != 0 {
+            process_exceptional_status(target >> 8, status);
+        }
+    }
+}
+
+pub extern fn input_timestamp(timeout: i64, channel: i32) -> i64 {
+    unsafe {
+        csr::rtio::target_write((channel as u32) << 8);
+        csr::rtio::i_timeout_write(timeout as u64);
+
+        let mut status = RTIO_I_STATUS_WAIT_STATUS;
+        while status & RTIO_I_STATUS_WAIT_STATUS != 0 {
+            status = csr::rtio::i_status_read();
+        }
+
+        if status & RTIO_I_STATUS_OVERFLOW != 0 {
+            csr::rtio::i_overflow_reset_write(1);
+            println!("RTIO input overflow on channel {0}",
+                channel as i64);
+        }
+        if status & RTIO_I_STATUS_WAIT_EVENT != 0 {
+            return -1
+        }
+        if status & RTIO_I_STATUS_DESTINATION_UNREACHABLE != 0 {
+            println!("RTIO destination unreachable, input, on channel {0}",
+                channel as i64);
+        }
+
+        csr::rtio::i_timestamp_read() as i64
+    }
+}
+
+pub extern fn input_data(channel: i32) -> i32 {
+    unsafe {
+        csr::rtio::target_write((channel as u32) << 8);
+        csr::rtio::i_timeout_write(0xffffffff_ffffffff);
+
+        let mut status = RTIO_I_STATUS_WAIT_STATUS;
+        while status & RTIO_I_STATUS_WAIT_STATUS != 0 {
+            status = csr::rtio::i_status_read();
+        }
+
+        if status & RTIO_I_STATUS_OVERFLOW != 0 {
+            csr::rtio::i_overflow_reset_write(1);
+            println!("RTIO input overflow on channel {0}",
+                channel as i64);
+        }
+        if status & RTIO_I_STATUS_DESTINATION_UNREACHABLE != 0 {
+            println!("RTIO destination unreachable, input, on channel {0}",
+                channel as i64);
+        }
+
+        rtio_i_data_read(0) as i32
+    }
+}
+
+pub extern fn input_timestamped_data(timeout: i64, channel: i32) -> TimestampedData {
+    unsafe {
+        csr::rtio::target_write((channel as u32) << 8);
+        csr::rtio::i_timeout_write(timeout as u64);
+
+        let mut status = RTIO_I_STATUS_WAIT_STATUS;
+        while status & RTIO_I_STATUS_WAIT_STATUS != 0 {
+            status = csr::rtio::i_status_read();
+        }
+
+        if status & RTIO_I_STATUS_OVERFLOW != 0 {
+            csr::rtio::i_overflow_reset_write(1);
+            println!("RTIO input overflow on channel {0}",
+                channel as i64);
+        }
+        if status & RTIO_I_STATUS_WAIT_EVENT != 0 {
+            return TimestampedData { timestamp: -1, data: 0 }
+        }
+        if status & RTIO_I_STATUS_DESTINATION_UNREACHABLE != 0 {
+            println!("RTIO destination unreachable, input, on channel {0}",
+                channel as i64);
+        }
+
+        TimestampedData {
+            timestamp: csr::rtio::i_timestamp_read() as i64,
+            data: rtio_i_data_read(0) as i32
+        }
+    }
+}