tock · alevy · May 21, 2025 · Apr 30, 2025 · Apr 30, 2025 · May 1, 2025
diff --git a/Cargo.toml b/Cargo.toml
@@ -61,6 +61,7 @@ members = [
     "boards/configurations/nrf52840dk/nrf52840dk-test-kernel",
     "boards/configurations/nrf52840dk/nrf52840dk-test-dynamic-app-load",
     "boards/configurations/microbit_v2/microbit_v2-test-dynamic-app-load",
+    "boards/tutorials/nrf52840dk-dynamic-apps-and-policies",
     "boards/tutorials/nrf52840dk-hotp-tutorial",
     "boards/tutorials/nrf52840dk-thread-tutorial",
     "capsules/aes_gcm",

diff --git a/boards/components/src/process_info_driver.rs b/boards/components/src/process_info_driver.rs
@@ -13,10 +13,10 @@ use kernel::create_capability;
 
 #[macro_export]
 macro_rules! process_info_component_static {
-    () => {{
+    ($C:ty $(,)?) => {{
         let process_info = kernel::static_buf!(
             capsules_extra::process_info_driver::ProcessInfo<
-                components::process_info_driver::Capability,
+                $C,
             >
         );
 
@@ -43,13 +43,13 @@ impl<C: ProcessManagementCapability + ProcessStartCapability> ProcessInfoCompone
 impl<C: ProcessManagementCapability + ProcessStartCapability + 'static> Component
     for ProcessInfoComponent<C>
 {
-    type StaticInput = (&'static mut MaybeUninit<ProcessInfo<C>>,);
+    type StaticInput = &'static mut MaybeUninit<ProcessInfo<C>>;
     type Output = &'static process_info_driver::ProcessInfo<C>;
 
     fn finalize(self, static_buffer: Self::StaticInput) -> Self::Output {
         let grant_cap = create_capability!(capabilities::MemoryAllocationCapability);
 
-        let process_info = static_buffer.0.write(ProcessInfo::new(
+        let process_info = static_buffer.write(ProcessInfo::new(
             self.board_kernel,
                self.board_kernel.create_grant(self.driver_num, &grant_cap),
             self.capability,

diff --git a/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/.cargo/config.toml b/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/.cargo/config.toml
@@ -0,0 +1,14 @@
+# Licensed under the Apache License, Version 2.0 or the MIT License.
+# SPDX-License-Identifier: Apache-2.0 OR MIT
+# Copyright Tock Contributors 2024.
+
+include = [
+  "../../../cargo/tock_flags.toml",
+  "../../../cargo/unstable_flags.toml",
+]
+
+[build]
+target = "thumbv7em-none-eabi"
+
+[unstable]
+config-include = true
diff --git a/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/Cargo.toml b/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/Cargo.toml
@@ -0,0 +1,34 @@
+# Licensed under the Apache License, Version 2.0 or the MIT License.
+# SPDX-License-Identifier: Apache-2.0 OR MIT
+# Copyright Tock Contributors 2022.
+
+[package]
+name = "nrf52840dk-dynamic-apps-and-policies"
+version.workspace = true
+authors.workspace = true
+build = "../../build.rs"
+edition.workspace = true
+
+[features]
+default = ["screen_ssd1306"]
+screen_ssd1306 = []
+screen_sh1106 = []
+
+[dependencies]
+kernel = { path = "../../../kernel" }
+
+components = { path = "../../components" }
+segger = { path = "../../../chips/segger" }
+cortexm4 = { path = "../../../arch/cortex-m4" }
+nrf52840 = { path = "../../../chips/nrf52840" }
+nrf52840dk = { path = "../../nordic/nrf52840dk" }
+capsules-core = { path = "../../../capsules/core" }
+capsules-extra = { path = "../../../capsules/extra" }
+capsules-system = { path = "../../../capsules/system" }
+nrf52_components = { path = "../../nordic/nrf52_components" }
+
+[build-dependencies]
+tock_build_scripts = { path = "../../build_scripts" }
+
+[lints]
+workspace = true
diff --git a/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/Makefile b/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/Makefile
@@ -0,0 +1,6 @@
+# Licensed under the Apache License, Version 2.0 or the MIT License.
+# SPDX-License-Identifier: Apache-2.0 OR MIT
+# Copyright Tock Contributors 2022.
+
+include ../../Makefile.common
+include ../../configurations/nrf52840dk/nrf52840dk.mk
diff --git a/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/README.md b/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/README.md
@@ -0,0 +1,10 @@
+nRF52840DK Board Definition for the Tock Dynamic Apps and Secure Policies Tutorial
+==================================================================================
+
+This is the board definition for the nRF52840DK target used in the
+[Dynamic App Loading and Secure Policies]
+(https://github.com/tock/book/pull/60/files).
+
+Please follow the instructions in that tutorial. You may also want to look at
+the documentation of the base nRF52840DK board definition
+[here](../../nordic/nrf52840dk/README.md).
diff --git a/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/layout.ld b/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/layout.ld
@@ -0,0 +1,6 @@
+/* Licensed under the Apache License, Version 2.0 or the MIT License. */
+/* SPDX-License-Identifier: Apache-2.0 OR MIT                         */
+/* Copyright Tock Contributors 2023.                                  */
+
+INCLUDE ../../nordic/nrf52840_chip_layout.ld
+INCLUDE tock_kernel_layout.ld
diff --git a/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/src/app_id_assigner_name_metadata.rs b/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/src/app_id_assigner_name_metadata.rs
@@ -0,0 +1,73 @@
+// Licensed under the Apache License, Version 2.0 or the MIT License.
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+// Copyright Tock Contributors 2025.
+
+//! AppID assigner based on name and credential check metadata.
+//!
+//! This assigns a short ID where the most significant four bits are from the
+//! credential checking metadata and the remaining bits are a CRC of the name.
+//!
+//! ```text
+//! 32         28                       0 bits
+//! +----------+------------------------+
+//! | metadata | CRC(name)              |
+//! +----------+------------------------+
+//! ```
+//!
+//! The intention is that the CRC makes the short ID generally unique, and the
+//! 4-bit metadata indicates the key that was used to verify the app's signing
+//! credential.
+
+use kernel::process::{Process, ProcessBinary, ShortId};
+use kernel::process_checker::Compress;
+
+pub struct AppIdAssignerNameMetadata {}
+
+impl AppIdAssignerNameMetadata {
+    pub fn new() -> Self {
+        Self {}
+    }
+}
+
+impl kernel::process_checker::Compress for AppIdAssignerNameMetadata {
+    fn to_short_id(&self, process: &ProcessBinary) -> ShortId {
+        // Get the stored metadata returned when this process had its credential
+        // checked.
+        let metadata = process.credential.get().map_or(0xF, |accepted_credential| {
+            accepted_credential
+                .metadata
+                .map_or(0xF, |metadata| metadata.metadata) as u32
+        });
+
+        let name = process.header.get_package_name().unwrap_or("");
+        let sum = kernel::utilities::helpers::crc32_posix(name.as_bytes());
+
+        // Combine the metadata and CRC into the short id.
+        let sid = ((metadata & 0xF) << 28) | (sum & 0xFFFFFFF);
+
+        core::num::NonZeroU32::new(sid).into()
+    }
+}
+
+// We just use the generic version which compares Short IDs.
+impl kernel::process_checker::AppUniqueness for AppIdAssignerNameMetadata {
+    fn different_identifier(&self, process_a: &ProcessBinary, process_b: &ProcessBinary) -> bool {
+        self.to_short_id(process_a) != self.to_short_id(process_b)
+    }
+
+    fn different_identifier_process(
+        &self,
+        process_a: &ProcessBinary,
+        process_b: &dyn Process,
+    ) -> bool {
+        self.to_short_id(process_a) != process_b.short_app_id()
+    }
+
+    fn different_identifier_processes(
+        &self,
+        process_a: &dyn Process,
+        process_b: &dyn Process,
+    ) -> bool {
+        process_a.short_app_id() != process_b.short_app_id()
+    }
+}
diff --git a/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/src/io.rs b/boards/tutorials/nrf52840dk-dynamic-apps-and-policies/src/io.rs
@@ -0,0 +1,90 @@
+// Licensed under the Apache License, Version 2.0 or the MIT License.
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+// Copyright Tock Contributors 2024.
+
+use core::fmt::Write;
+use kernel::debug::IoWrite;
+use kernel::hil::uart;
+use kernel::hil::uart::Configure;
+
+use nrf52840::uart::{Uarte, UARTE0_BASE};
+
+enum Writer {
+    WriterUart(/* initialized */ bool),
+    WriterRtt(&'static segger::rtt::SeggerRttMemory<'static>),
+}
+
+static mut WRITER: Writer = Writer::WriterUart(false);
+
+/// Set the RTT memory buffer used to output panic messages.
+pub unsafe fn set_rtt_memory(rtt_memory: &'static segger::rtt::SeggerRttMemory<'static>) {
+    WRITER = Writer::WriterRtt(rtt_memory);
+}
+
+impl Write for Writer {
+    fn write_str(&mut self, s: &str) -> ::core::fmt::Result {
+        self.write(s.as_bytes());
+        Ok(())
+    }
+}
+
+impl IoWrite for Writer {
+    fn write(&mut self, buf: &[u8]) -> usize {
+        match self {
+            Writer::WriterUart(ref mut initialized) => {
+                // Here, we create a second instance of the Uarte struct.
+                // This is okay because we only call this during a panic, and
+                // we will never actually process the interrupts
+                let uart = Uarte::new(UARTE0_BASE);
+                if !*initialized {
+                    *initialized = true;
+                    let _ = uart.configure(uart::Parameters {
+                        baud_rate: 115200,
+                        stop_bits: uart::StopBits::One,
+                        parity: uart::Parity::None,
+                        hw_flow_control: false,
+                        width: uart::Width::Eight,
+                    });
+                }
+                for &c in buf {
+                    unsafe {
+                        uart.send_byte(c);
+                    }
+                    while !uart.tx_ready() {}
+                }
+            }
+            Writer::WriterRtt(rtt_memory) => {
+                rtt_memory.write_sync(buf);
+            }
+        }
+        buf.len()
+    }
+}
+
+#[cfg(not(test))]
+#[panic_handler]
+/// Panic handler
+pub unsafe fn panic_fmt(pi: &core::panic::PanicInfo) -> ! {
+    use core::ptr::{addr_of, addr_of_mut};
+    use kernel::debug;
+    use kernel::hil::led;
+    use nrf52840::gpio::Pin;
+
+    use crate::CHIP;
+    use crate::PROCESSES;
+    use crate::PROCESS_PRINTER;
+
+    // The nRF52840DK LEDs (see back of board)
+    let led_kernel_pin = &nrf52840::gpio::GPIOPin::new(Pin::P0_13);
+    let led = &mut led::LedLow::new(led_kernel_pin);
+    let writer = &mut *addr_of_mut!(WRITER);
+    debug::panic(
+        &mut [led],
+        writer,
+        pi,
+        &cortexm4::support::nop,
+        &*addr_of!(PROCESSES),
+        &*addr_of!(CHIP),
+        &*addr_of!(PROCESS_PRINTER),
+    )
+}