Move RTT init after breakpoint setup

auxoncorp · Sep 17, 2024 · 466f240 · 466f240
1 parent 38f78ca
commit 466f240
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Showing 3 changed files with 45 additions and 41 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "trace-recorder-rtt-proxy"
-version = "0.5.0"
+version = "0.6.0"
 edition = "2021"
 authors = ["Jon Lamb <jon@auxon.io>"]
 description = "Proxy debug-probe operations and trace recorder RTT data over the network"

diff --git a/src/rtt_session.rs b/src/rtt_session.rs
@@ -180,36 +180,6 @@ fn rtt_session_thread(cfg: Config) -> Result<(), Error> {
         core.set_hw_breakpoint(bp_addr)?;
     }
 
-    let rtt = if let Some(to) = rtt_cfg.attach_timeout_ms {
-        attach_retry_loop(
-            &mut core,
-            &rtt_scan_region,
-            &interruptor,
-            Duration::from_millis(to.into()),
-        )?
-    } else {
-        debug!("Attaching to RTT");
-        Rtt::attach_region(&mut core, &rtt_scan_region)?
-    };
-    debug!(
-        addr = format_args!("0x{:X}", rtt.ptr()),
-        "Found RTT control block"
-    );
-
-    let up_channel = rtt
-        .up_channel(rtt_cfg.up_channel as _)
-        .ok_or(Error::UpChannelInvalid(rtt_cfg.up_channel as _))?;
-    let up_channel_mode = up_channel.mode(&mut core)?;
-    debug!(channel = up_channel.number(), mode = ?up_channel_mode, buffer_size = up_channel.buffer_size(), "Opened up channel");
-    let down_channel = rtt
-        .down_channel(rtt_cfg.down_channel as _)
-        .ok_or(Error::DownChannelInvalid(rtt_cfg.down_channel as _))?;
-    debug!(
-        channel = down_channel.number(),
-        buffer_size = down_channel.buffer_size(),
-        "Opened down channel"
-    );
-
     // Start the core if it's halted
     if target_cfg.reset || !matches!(core_status, CoreStatus::Running) {
         let sp_reg = core.stack_pointer();
@@ -220,26 +190,26 @@ fn rtt_session_thread(cfg: Config) -> Result<(), Error> {
         core.run()?;
     }
 
-    // We've done the initial setup, release the lock and switch over to on-demand sessions
-    std::mem::drop(core);
-    std::mem::drop(session);
-
     if rtt_cfg.setup_on_breakpoint_address.is_some() {
         debug!("Waiting for breakpoint");
         'bp_loop: loop {
             if interruptor.is_set() {
                 break;
             }
 
-            let core_status = session_op(&session_mutex, |session| {
-                let mut core = session.core(target_cfg.core as _)?;
-                Ok(core.status()?)
-            })?;
+            let core_status = core.status()?;
 
             match core_status {
                 CoreStatus::Running => (),
                 CoreStatus::Halted(halt_reason) => match halt_reason {
-                    HaltReason::Breakpoint(_) => break 'bp_loop,
+                    HaltReason::Breakpoint(_) => {
+                        let sp_reg = core.stack_pointer();
+                        let sp: RegisterValue = core.read_core_reg(sp_reg.id())?;
+                        let pc_reg = core.program_counter();
+                        let pc: RegisterValue = core.read_core_reg(pc_reg.id())?;
+                        debug!(pc = %pc, sp = %sp, "Breakpoint hit");
+                        break 'bp_loop;
+                    }
                     _ => {
                         warn!(reason = ?halt_reason, "Unexpected halt reason");
                         break 'bp_loop;
@@ -257,6 +227,40 @@ fn rtt_session_thread(cfg: Config) -> Result<(), Error> {
         // The core is run below
     }
 
+    let rtt = if let Some(to) = rtt_cfg.attach_timeout_ms {
+        attach_retry_loop(
+            &mut core,
+            &rtt_scan_region,
+            &interruptor,
+            Duration::from_millis(to.into()),
+        )?
+    } else {
+        debug!("Attaching to RTT");
+        Rtt::attach_region(&mut core, &rtt_scan_region)?
+    };
+    debug!(
+        addr = format_args!("0x{:X}", rtt.ptr()),
+        "Found RTT control block"
+    );
+
+    let up_channel = rtt
+        .up_channel(rtt_cfg.up_channel as _)
+        .ok_or(Error::UpChannelInvalid(rtt_cfg.up_channel as _))?;
+    let up_channel_mode = up_channel.mode(&mut core)?;
+    debug!(channel = up_channel.number(), mode = ?up_channel_mode, buffer_size = up_channel.buffer_size(), "Opened up channel");
+    let down_channel = rtt
+        .down_channel(rtt_cfg.down_channel as _)
+        .ok_or(Error::DownChannelInvalid(rtt_cfg.down_channel as _))?;
+    debug!(
+        channel = down_channel.number(),
+        buffer_size = down_channel.buffer_size(),
+        "Opened down channel"
+    );
+
+    // We've done the initial setup, release the lock and switch over to on-demand sessions
+    std::mem::drop(core);
+    std::mem::drop(session);
+
     session_op(&session_mutex, |session| {
         let mut core = session.core(target_cfg.core as _)?;