cpu/avr8_common: Add support to threadless idle

Signed-off-by: Gerson Fernando Budke <[email protected]>
RIOT-OS · Jun 18, 2023 · 6c6063e · 6c6063e
1 parent 1bed7dd
commit 6c6063e
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Showing 4 changed files with 22 additions and 0 deletions.
diff --git a/cpu/avr8_common/Kconfig b/cpu/avr8_common/Kconfig
@@ -10,6 +10,7 @@ config CPU_ARCH_AVR8
     bool
     select HAS_ARCH_8BIT
     select HAS_ARCH_AVR8
+    select HAS_NO_IDLE_THREAD
 
     select MODULE_MALLOC_THREAD_SAFE if TEST_KCONFIG
     select MODULE_TINY_STRERROR_AS_STRERROR if TEST_KCONFIG

diff --git a/cpu/avr8_common/Makefile.features b/cpu/avr8_common/Makefile.features
@@ -1,3 +1,4 @@
 FEATURES_PROVIDED += arch_8bit
 FEATURES_PROVIDED += arch_avr8
+FEATURES_PROVIDED += no_idle_thread
 FEATURES_PROVIDED += cpp
diff --git a/cpu/avr8_common/avr8_cpu.c b/cpu/avr8_common/avr8_cpu.c
@@ -29,6 +29,7 @@
 #include <avr/io.h>
 #include <avr/wdt.h>
 #include <avr/pgmspace.h>
+#include <avr/sleep.h>
 
 #include "cpu.h"
 #include "cpu_clock.h"
@@ -101,6 +102,9 @@ void cpu_init(void)
 
     avr8_clk_init();
 
+    /* Set default sleep mode for LPM or threadless idle */
+    set_sleep_mode(SLEEP_MODE_IDLE);
+
     /* Initialize stdio before periph_init() to allow use of DEBUG() there */
 #ifdef MODULE_AVR_LIBC_EXTRA
     avr8_stdio_init();

diff --git a/cpu/avr8_common/thread_arch.c b/cpu/avr8_common/thread_arch.c
@@ -26,6 +26,7 @@
  */
 
 #include <stdio.h>
+#include <avr/sleep.h>
 
 #include "thread.h"
 #include "sched.h"
@@ -427,3 +428,18 @@ __attribute__((always_inline)) static inline void avr8_context_restore(void)
         "out  __SREG__, __tmp_reg__              \n\t"
         "pop  __tmp_reg__                        \n\t");
 }
+
+void sched_arch_idle(void)
+{
+#ifdef MODULE_PM_LAYERED
+    void pm_set_lowest(void);
+    pm_set_lowest();
+#else
+    unsigned irq_state = irq_disable();
+    sleep_enable();
+    sei();
+    sleep_cpu();
+    sleep_disable();
+    irq_restore(irq_state);
+#endif
+}