track runtime corruption

runtime_crc.diff

diff --git a/artiq/firmware/runtime/Cargo.toml b/artiq/firmware/runtime/Cargo.toml
index f7eb87ac..6c36c0fa 100644
--- a/artiq/firmware/runtime/Cargo.toml
+++ b/artiq/firmware/runtime/Cargo.toml
@@ -19,6 +19,7 @@ failure_derive = { version = "0.1", default-features = false }
 byteorder = { version = "1.0", default-features = false }
 cslice = { version = "0.3" }
 log = { version = "0.4", default-features = false }
+crc = { version = "1.7", default-features = false }
 managed = { version = "0.6", default-features = false, features = ["alloc", "map"] }
 unwind_backtrace = { path = "../libunwind_backtrace" }
 io = { path = "../libio", features = ["byteorder"] }
diff --git a/artiq/firmware/runtime/main.rs b/artiq/firmware/runtime/main.rs
index a0af6667..34bb1ca0 100644
--- a/artiq/firmware/runtime/main.rs
+++ b/artiq/firmware/runtime/main.rs
@@ -14,6 +14,7 @@ extern crate byteorder;
 extern crate fringe;
 extern crate managed;
 extern crate smoltcp;
+extern crate crc;
 
 extern crate alloc_list;
 extern crate unwind_backtrace;
@@ -24,10 +25,11 @@ extern crate board_artiq;
 extern crate logger_artiq;
 extern crate proto_artiq;
 
+use core::slice;
 use core::convert::TryFrom;
 use smoltcp::wire::{EthernetAddress, IpAddress, IpCidr};
 
-use board_misoc::{csr, irq, ident, clock, boot, config};
+use board_misoc::{csr, irq, ident, clock, boot, config, mem};
 #[cfg(has_ethmac)]
 use board_misoc::ethmac;
 #[cfg(has_drtio)]
@@ -61,6 +63,13 @@ const SYSREF_PHASE_FPGA: u16 = 20;
 #[cfg(has_ad9154)]
 const SYSREF_PHASE_DAC: u16 = 31;
 
+fn runtime_crc() {
+    // typical runtime size is 660k
+    let crc_area = unsafe { slice::from_raw_parts(mem::MAIN_RAM_BASE as *mut u8, 327680) };
+    let crc_val = crc::crc32::checksum_ieee(crc_area);
+    info!("runtime CRC: 0x{:08x}", crc_val);
+}
+
 fn startup() {
     irq::set_mask(0);
     irq::set_ie(true);
@@ -69,6 +78,8 @@ fn startup() {
     info!("software version {}", include_str!(concat!(env!("OUT_DIR"), "/git-describe")));
     info!("gateware version {}", ident::read(&mut [0; 64]));
 
+    runtime_crc();
+
     match config::read_str("log_level", |r| r.map(|s| s.parse())) {
         Ok(Ok(log_level_filter)) => {
             info!("log level set to {} by `log_level` config key",
@@ -89,8 +100,10 @@ fn startup() {
 
     #[cfg(has_slave_fpga_cfg)]
     board_artiq::slave_fpga::load().expect("cannot load RTM FPGA gateware");
+    runtime_crc();
     #[cfg(has_serwb_phy_amc)]
     board_artiq::serwb::wait_init();
+    runtime_crc();
 
     #[cfg(has_uart)] {
         let t = clock::get_ms();
@@ -110,13 +123,17 @@ fn startup() {
     board_artiq::i2c::init();
     #[cfg(si5324_as_synthesizer)]
     setup_si5324_as_synthesizer();
+    runtime_crc();
     #[cfg(has_hmc830_7043)]
     /* must be the first SPI init because of HMC830 SPI mode selection */
     board_artiq::hmc830_7043::init().expect("cannot initialize HMC830/7043");
+    runtime_crc();
     #[cfg(has_ad9154)]
     board_artiq::ad9154::init(SYSREF_PHASE_FPGA, SYSREF_PHASE_DAC);
+    runtime_crc();
     #[cfg(has_allaki_atts)]
     board_artiq::hmc542::program_all(8/*=4dB*/);
+    runtime_crc();
 
     #[cfg(has_ethmac)]
     startup_ethernet();
@@ -223,6 +240,8 @@ fn startup_ethernet() {
     let mut net_device = unsafe { ethmac::EthernetDevice::new() };
     net_device.reset_phy_if_any();
 
+    runtime_crc();
+
     let net_device = {
         use smoltcp::wire::PrettyPrinter;
         use smoltcp::wire::EthernetFrame;
@@ -253,6 +272,8 @@ fn startup_ethernet() {
                        .ip_addrs([IpCidr::new(protocol_addr, 0)])
                        .finalize();
 
+    runtime_crc();
+
     let mut scheduler = sched::Scheduler::new();
     let io = scheduler.io();
     #[cfg(has_rtio_core)]
@@ -266,10 +287,20 @@ fn startup_ethernet() {
     #[cfg(has_grabber)]
     io.spawn(4096, grabber_thread);
 
+    runtime_crc();
+
+    let mut t = clock::get_ms();
+
     let mut net_stats = ethmac::EthernetStatistics::new();
     loop {
         scheduler.run();
 
+        let now = clock::get_ms();
+        if now > t + 1000 {
+            runtime_crc();
+            t = now;
+        }
+
         {
             let sockets = &mut *scheduler.sockets().borrow_mut();
             loop {