Use GPIO instead of memory poking for SP reset

oxidecomputer · Apr 5, 2024 · e5380fb · e5380fb
1 parent e544709
commit e5380fb
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Showing 4 changed files with 24 additions and 8 deletions.
diff --git a/app/oxide-rot-1/app-dev.toml b/app/oxide-rot-1/app-dev.toml
@@ -132,6 +132,7 @@ pins = [
     # SCK
     { pin = { port = 0, pin = 7 }, alt = 3 },
     { name = "SP_TO_ROT_JTAG_DETECT_L", pin = { port = 0, pin = 20 }, alt = 0, direction = "input" },
+    { name = "ROT_TO_SP_RESET_L", pin = { port = 0, pin = 13 }, alt = 0, value = true, direction = "output" },
 ]
 spi_num = 5
 

diff --git a/app/oxide-rot-1/app.toml b/app/oxide-rot-1/app.toml
@@ -122,6 +122,7 @@ pins = [
     # SCK
     { pin = { port = 0, pin = 7 }, alt = 3 },
     { name = "SP_TO_ROT_JTAG_DETECT_L", pin = { port = 0, pin = 20 }, alt = 0, direction = "input" },
+    { name = "ROT_TO_SP_RESET_L", pin = { port = 0, pin = 13 }, alt = 0, value = true, direction = "output" },
 ]
 spi_num = 5
 

diff --git a/build/lpc55pins/src/lib.rs b/build/lpc55pins/src/lib.rs
@@ -46,6 +46,7 @@ pub struct PinConfig {
     digimode: Option<String>,
     opendrain: Option<String>,
     direction: Option<String>,
+    value: Option<bool>,
     name: Option<String>,
 }
 
@@ -135,6 +136,22 @@ pub fn codegen(pins: Vec<PinConfig>) -> Result<()> {
         writeln!(&mut file, "iocon.iocon_configure(")?;
         writeln!(&mut file, "{}", p.to_token_stream())?;
         writeln!(&mut file, ");")?;
+
+        // Output pins can specify their value, which is set before configuring
+        // their output mode (to avoid glitching).
+        if let Some(v) = p.value {
+            assert!(
+                matches!(p.direction.as_deref(), Some("output")),
+                "can only set value for output pins"
+            );
+            writeln!(&mut file, "iocon.set_val(")?;
+            writeln!(&mut file, "{}", p.pin.to_token_stream())?;
+            writeln!(
+                &mut file,
+                "{});",
+                if v { "Value::One" } else { "Value::Zero" }
+            )?;
+        }
         match p.direction {
             None => (),
             Some(d) => {

diff --git a/drv/lpc55-swd/src/main.rs b/drv/lpc55-swd/src/main.rs
@@ -1064,14 +1064,11 @@ impl ServerImpl {
         }
 
         // Reset the STM32, causing it to reboot into the newly-set slot
-        // Details from PM0253, Section 4.3.5
-        const AIRCR: u32 = 0xE000ED0C;
-        const AIRCR_VECTKEY: u32 = 0x5FA << 16;
-        const AIRCR_SYSRESETREQ: u32 = 1 << 2;
-        self.write_single_target_addr(
-            AIRCR,
-            AIRCR_VECTKEY | AIRCR_SYSRESETREQ,
-        )?;
+        use drv_lpc55_gpio_api::{Pins, Value};
+        let gpio = Pins::from(self.gpio);
+        gpio.set_val(ROT_TO_SP_RESET_L, Value::Zero);
+        hl::sleep_for(10);
+        gpio.set_val(ROT_TO_SP_RESET_L, Value::One);
 
         Ok(())
     }