[console][panic] slight tweak to where the panic shell define is set

Tweak the default platform_halt to idle the core if fully wedged.

lib/console/include/lib/console.h

@@ -29,3 +29,9 @@ void panic_shell_start(void);
 
 extern int lastresult;
 
+/* enable the panic shell if we're being built */
+#if !defined(ENABLE_PANIC_SHELL) && PLATFORM_SUPPORTS_PANIC_SHELL
+#define ENABLE_PANIC_SHELL 1
+#endif
+
+

platform/power.c

@@ -8,11 +8,11 @@
 #include <lk/debug.h>
 #include <lk/err.h>
 #include <lk/compiler.h>
+#include <lk/console_cmd.h>
 #include <platform.h>
 #include <platform/debug.h>
 #include <kernel/thread.h>
 #include <stdio.h>
-#include <lk/console_cmd.h>
 
 #if WITH_LIB_CONSOLE
 #include <lib/console.h>
@@ -24,19 +24,18 @@
  */
 __WEAK void platform_halt(platform_halt_action suggested_action,
                           platform_halt_reason reason) {
-#if WITH_LIB_CONSOLE && ENABLE_PANIC_SHELL
-
+#if ENABLE_PANIC_SHELL
     if (reason == HALT_REASON_SW_PANIC) {
         dprintf(ALWAYS, "CRASH: starting debug shell... (reason = %d)\n", reason);
         arch_disable_ints();
         panic_shell_start();
     }
-
 #endif  // ENABLE_PANIC_SHELL
 
     dprintf(ALWAYS, "HALT: spinning forever... (reason = %d)\n", reason);
     arch_disable_ints();
-    for (;;);
+    for (;;)
+        arch_idle();
 }
 
 static int cmd_reboot(int argc, const cmd_args *argv) {

platform/stm32/power.c

@@ -8,12 +8,17 @@
 #include <lk/debug.h>
 #include <lk/err.h>
 #include <lk/compiler.h>
+#include <lk/console_cmd.h>
 #include <stdio.h>
 #include <platform.h>
 #include <platform/debug.h>
 #include <arch/ops.h>
 #include <arch/arm/cm.h>
 
+#if WITH_LIB_CONSOLE
+#include <lib/console.h>
+#endif
+
 void platform_halt(platform_halt_action suggested_action,
                    platform_halt_reason reason) {
 #if ENABLE_PANIC_SHELL

top/include/lk/console_cmd.h

@@ -47,16 +47,12 @@ typedef struct _cmd_block {
  */
 #if WITH_LIB_CONSOLE
 
-/* enable the panic shell if we're being built */
-#if !defined(ENABLE_PANIC_SHELL) && PLATFORM_SUPPORTS_PANIC_SHELL
-#define ENABLE_PANIC_SHELL 1
-#endif
-
 #define STATIC_COMMAND_START static const cmd _cmd_list[] = {
 
 #define STATIC_COMMAND_END(name) }; cmd_block _cmd_block_##name __ALIGNED(sizeof(void *)) __SECTION(".commands") = \
     { NULL, sizeof(_cmd_list) / sizeof(_cmd_list[0]), _cmd_list }
 
+/* same as above but with a suffixed name to make the list unique within the file */
 #define STATIC_COMMAND_START_NAMED(name) static const cmd _cmd_list_##name[] = {
 
 #define STATIC_COMMAND_END_NAMED(name) }; cmd_block _cmd_block_##name __ALIGNED(sizeof(void *)) __SECTION(".commands") = \