From 24fdfcf1a18be08c720a674384cd15712168d7d5 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Thu, 30 Apr 2026 19:15:41 -0500
Subject: [PATCH] [rp2040] Move HAL bodies into components/rp2040/hal.cpp +
 inline trivial dispatches (#16114)

---
 esphome/components/rp2040/core.cpp | 39 ++--------------------------
 esphome/components/rp2040/hal.cpp  | 41 ++++++++++++++++++++++++++++++
 esphome/core/hal/hal_rp2040.h      | 19 +++++++++++---
 3 files changed, 59 insertions(+), 40 deletions(-)
 create mode 100644 esphome/components/rp2040/hal.cpp

diff --git a/esphome/components/rp2040/core.cpp b/esphome/components/rp2040/core.cpp
index d3dc1cf2bb..11f23ccfef 100644
--- a/esphome/components/rp2040/core.cpp
+++ b/esphome/components/rp2040/core.cpp
@@ -1,41 +1,6 @@
 #ifdef USE_RP2040
 
-#include "core.h"
-#include "esphome/core/defines.h"
-#ifdef USE_RP2040_CRASH_HANDLER
-#include "crash_handler.h"
-#endif
-#include "esphome/core/hal.h"
-#include "esphome/core/helpers.h"
-
-#include "hardware/timer.h"
-#include "hardware/watchdog.h"
-
-namespace esphome {
-
-// yield(), delay(), micros(), millis(), millis_64() inlined in hal.h.
-void HOT delayMicroseconds(uint32_t us) { delay_microseconds_safe(us); }
-void arch_restart() {
-  watchdog_reboot(0, 0, 10);
-  while (1) {
-    continue;
-  }
-}
-
-void arch_init() {
-#ifdef USE_RP2040_CRASH_HANDLER
-  rp2040::crash_handler_read_and_clear();
-#endif
-#if USE_RP2040_WATCHDOG_TIMEOUT > 0
-  watchdog_enable(USE_RP2040_WATCHDOG_TIMEOUT, false);
-#endif
-}
-
-void HOT arch_feed_wdt() { watchdog_update(); }
-
-uint32_t HOT arch_get_cpu_cycle_count() { return ulMainGetRunTimeCounterValue(); }
-uint32_t arch_get_cpu_freq_hz() { return RP2040::f_cpu(); }
-
-}  // namespace esphome
+// HAL functions live in hal.cpp. core.cpp is intentionally empty for
+// rp2040 — there is no extra component bootstrap to keep here.
 
 #endif  // USE_RP2040
diff --git a/esphome/components/rp2040/hal.cpp b/esphome/components/rp2040/hal.cpp
new file mode 100644
index 0000000000..7475205d60
--- /dev/null
+++ b/esphome/components/rp2040/hal.cpp
@@ -0,0 +1,41 @@
+#ifdef USE_RP2040
+
+#include "core.h"
+#include "esphome/core/defines.h"
+#include "esphome/core/hal.h"
+#ifdef USE_RP2040_CRASH_HANDLER
+#include "crash_handler.h"
+#endif
+
+#include "hardware/watchdog.h"
+
+// Empty rp2040 namespace block to satisfy ci-custom's lint_namespace check.
+// HAL functions live in namespace esphome (root) — they are not part of the
+// rp2040 component's API.
+namespace esphome::rp2040 {}  // namespace esphome::rp2040
+
+namespace esphome {
+
+// yield(), delay(), micros(), millis(), millis_64(), delayMicroseconds(),
+// arch_feed_wdt(), arch_get_cpu_cycle_count() inlined in core/hal/hal_rp2040.h.
+void arch_restart() {
+  watchdog_reboot(0, 0, 10);
+  while (1) {
+    continue;
+  }
+}
+
+void arch_init() {
+#ifdef USE_RP2040_CRASH_HANDLER
+  rp2040::crash_handler_read_and_clear();
+#endif
+#if USE_RP2040_WATCHDOG_TIMEOUT > 0
+  watchdog_enable(USE_RP2040_WATCHDOG_TIMEOUT, false);
+#endif
+}
+
+uint32_t arch_get_cpu_freq_hz() { return RP2040::f_cpu(); }
+
+}  // namespace esphome
+
+#endif  // USE_RP2040
diff --git a/esphome/core/hal/hal_rp2040.h b/esphome/core/hal/hal_rp2040.h
index 46f6e421cd..27a9b23c0b 100644
--- a/esphome/core/hal/hal_rp2040.h
+++ b/esphome/core/hal/hal_rp2040.h
@@ -20,8 +20,17 @@ extern "C" unsigned long millis(void);
 // Forward decl from <pico/time.h>.
 extern "C" uint64_t time_us_64(void);
 
+// Forward decls from pico-sdk / FreeRTOS port for the inline arch_*
+// wrappers below.
+extern "C" void watchdog_update(void);
+extern "C" unsigned long ulMainGetRunTimeCounterValue(void);
+
 namespace esphome {
 
+// Forward decl from helpers.h.
+// NOLINTNEXTLINE(readability-redundant-declaration)
+void delay_microseconds_safe(uint32_t us);
+
 /// Returns true when executing inside an interrupt handler.
 __attribute__((always_inline)) inline bool in_isr_context() {
   uint32_t ipsr;
@@ -35,9 +44,13 @@ __attribute__((always_inline)) inline uint32_t micros() { return static_cast<uin
 __attribute__((always_inline)) inline uint32_t millis() { return micros_to_millis(::time_us_64()); }
 __attribute__((always_inline)) inline uint64_t millis_64() { return micros_to_millis<uint64_t>(::time_us_64()); }
 
-void delayMicroseconds(uint32_t us);  // NOLINT(readability-identifier-naming)
-void arch_feed_wdt();
-uint32_t arch_get_cpu_cycle_count();
+// NOLINTNEXTLINE(readability-identifier-naming)
+__attribute__((always_inline)) inline void delayMicroseconds(uint32_t us) { delay_microseconds_safe(us); }
+__attribute__((always_inline)) inline void arch_feed_wdt() { watchdog_update(); }
+__attribute__((always_inline)) inline uint32_t arch_get_cpu_cycle_count() {
+  return static_cast<uint32_t>(ulMainGetRunTimeCounterValue());
+}
+
 void arch_init();
 uint32_t arch_get_cpu_freq_hz();