Move the thermal config from RAM into flash (oxidecomputer#838)

This brings the thermal task from 18648 to 17720 bytes of flash (a small
improvement)

More importantly, it drops the stack usage from 7392 to 3560, meaning we can
shrink the RAM usage by 8192!

app/gimlet/rev-b.toml

@@ -120,8 +120,8 @@ task-slots = ["sys", "i2c_driver"]
 name = "task-thermal"
 features = ["itm", "gimlet"]
 priority = 5
-max-sizes = {flash = 32768, ram = 16384 }
-stacksize = 8000
+max-sizes = {flash = 32768, ram = 8192 }
+stacksize = 4504
 start = true
 task-slots = ["i2c_driver", "sensor", "gimlet_seq", "jefe"]
 
@@ -438,7 +438,8 @@ segment = 1
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 A NVMe Basic Management Command"
-sensors = { temperature = 1, names = ["U2_N0"] }
+sensors = { temperature = 1 }
+name = "U2_N0"
 refdes = "J206"
 removable = true
 
@@ -469,7 +470,8 @@ segment = 2
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 B NVMe Basic Management Control"
-sensors = { temperature = 1, names = ["U2_N1"] }
+sensors = { temperature = 1 }
+name = "U2_N1"
 refdes = "J207"
 removable = true
 
@@ -500,7 +502,8 @@ segment = 3
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 C NVMe Basic Management Control"
-sensors = { temperature = 1, names = ["U2_N2"] }
+sensors = { temperature = 1 }
+name = "U2_N2"
 refdes = "J208"
 removable = true
 
@@ -531,7 +534,8 @@ segment = 4
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 D NVMe Basic Management Control"
-sensors = { temperature = 1, names = ["U2_N3"] }
+sensors = { temperature = 1 }
+name = "U2_N3"
 refdes = "J209"
 removable = true
 
@@ -562,7 +566,8 @@ segment = 1
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 E NVMe Basic Management Control"
-sensors = { temperature = 1, names = ["U2_N4"] }
+sensors = { temperature = 1 }
+name = "U2_N4"
 refdes = "J210"
 removable = true
 
@@ -593,7 +598,8 @@ segment = 2
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 F NVMe Basic Management Control"
-sensors = { temperature = 1, names = ["U2_N5"] }
+sensors = { temperature = 1 }
+name = "U2_N5"
 refdes = "J211"
 removable = true
 
@@ -624,7 +630,8 @@ segment = 3
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 G NVMe Basic Management Control"
-sensors = { temperature = 1, names = ["U2_N6"] }
+sensors = { temperature = 1 }
+name = "U2_N6"
 refdes = "J212"
 removable = true
 
@@ -655,7 +662,8 @@ segment = 4
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 H NVMe Basic Management Control"
-sensors = { temperature = 1, names = ["U2_N7"] }
+sensors = { temperature = 1 }
+name = "U2_N7"
 refdes = "J213"
 removable = true
 
@@ -686,7 +694,8 @@ segment = 1
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 I NVMe Basic Management Control"
-sensors = { temperature = 1, names = ["U2_N8"] }
+sensors = { temperature = 1 }
+name = "U2_N8"
 refdes = "J214"
 removable = true
 
@@ -717,7 +726,8 @@ segment = 2
 address = 0b110_1010
 device = "nvmebmc"
 description = "U.2 J NVMe Basic Management Control"
-sensors = { temperature = 1, names = ["U2_N9"] }
+sensors = { temperature = 1 }
+name = "U2_N9"
 refdes = "J215"
 removable = true
 
@@ -753,6 +763,7 @@ mux = 1
 segment = 4
 address = 0x4c
 device = "tmp451"
+name = "t6"
 sensors = { temperature = 1 }
 description = "T6 temperature sensor"
 refdes = "U491"

build/i2c/src/lib.rs

@@ -319,7 +319,7 @@ impl ConfigGenerator {
     }
 
     pub fn generate_header(&mut self) -> Result<()> {
-        writeln!(&mut self.output, "mod i2c_config {{")?;
+        writeln!(&mut self.output, "pub(crate) mod i2c_config {{")?;
         Ok(())
     }
 

drv/i2c-devices/src/tmp451.rs

@@ -50,6 +50,7 @@ impl From<Error> for ResponseCode {
 }
 
 /// Selects whether this sensor reads the local or remote temperature
+#[derive(Copy, Clone)]
 pub enum Target {
     Local,
     Remote,