[nap] Formalise the CPU sleeping API

src/arch/i386/core/nap.c

@@ -1,12 +0,0 @@
-
-#include <realmode.h>
-#include <bios.h>
-
-/**************************************************************************
- * Save power by halting the CPU until the next interrupt
- **************************************************************************/
-void cpu_nap ( void ) {
-	__asm__ __volatile__ ( REAL_CODE ( "sti\n\t"
-					   "hlt\n\t"
-					   "cli\n\t" ) : : );
-}

src/arch/i386/include/bios.h

@@ -5,6 +5,4 @@
 #define BDA_FBMS 0x0013
 #define BDA_NUM_DRIVES 0x0075
 
-extern void cpu_nap ( void );
-
 #endif /* BIOS_H */

src/arch/i386/include/bits/nap.h

@@ -0,0 +1,12 @@
+#ifndef _BITS_NAP_H
+#define _BITS_NAP_H
+
+/** @file
+ *
+ * i386-specific CPU sleeping API implementations
+ *
+ */
+
+#include <gpxe/bios_nap.h>
+
+#endif /* _BITS_MAP_H */

src/arch/i386/include/gpxe/bios_nap.h

@@ -0,0 +1,16 @@
+#ifndef _GPXE_BIOS_NAP_H
+#define _GPXE_BIOS_NAP_H
+
+/** @file
+ *
+ * BIOS CPU sleeping
+ *
+ */
+
+#ifdef NAP_PCBIOS
+#define NAP_PREFIX_pcbios
+#else
+#define NAP_PREFIX_pcbios __pcbios_
+#endif
+
+#endif /* _GPXE_BIOS_NAP_H */

src/arch/i386/interface/pcbios/bios_nap.c

@@ -0,0 +1,14 @@
+#include <gpxe/nap.h>
+#include <realmode.h>
+
+/**
+ * Save power by halting the CPU until the next interrupt
+ *
+ */
+static void bios_cpu_nap ( void ) {
+	__asm__ __volatile__ ( REAL_CODE ( "sti\n\t"
+					   "hlt\n\t"
+					   "cli\n\t" ) : : );
+}
+
+PROVIDE_NAP ( pcbios, cpu_nap, bios_cpu_nap );