[build] Canonicalise console type configuration

Move all console configuration from config/defaults/<platform>.h to
the top-level config/console.h, using indented conditional blocks to
clarify which console types are supported and enabled on each
platform.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/config/console.h

@@ -15,52 +15,76 @@ FILE_SECBOOT ( PERMITTED );
 
 #include <config/defaults.h>
 
-/*
- * Default console types
+/*****************************************************************************
  *
- * These are all enabled by default for the appropriate platforms.
- * You may disable them if needed.
+ * Console types
  *
  */
 
-//#undef	CONSOLE_PCBIOS		/* Default BIOS console */
-//#undef	CONSOLE_EFI		/* Default EFI console */
-//#undef	CONSOLE_LINUX		/* Default Linux console */
-
-/*
- * Additional console types
- *
- * These are not enabled by default, but may be useful in your
- * environment.
- *
- */
-
-//#define	CONSOLE_SERIAL		/* Serial port console */
+/* Console types supported on all platforms */
 //#define CONSOLE_FRAMEBUFFER	/* Graphical framebuffer console */
 //#define CONSOLE_SYSLOG	/* Syslog console */
 //#define CONSOLE_SYSLOGS	/* Encrypted syslog console */
-//#define	CONSOLE_VMWARE		/* VMware logfile console */
-//#define	CONSOLE_DEBUGCON	/* Bochs/QEMU/KVM debug port console */
-//#define	CONSOLE_INT13		/* INT13 disk log console */
-//#define	CONSOLE_SBI		/* RISC-V SBI debug console */
 
-/*
- * Very obscure console types
+/* Console types supported only on systems with serial ports */
+#if ! defined ( SERIAL_NULL )
+  //#define CONSOLE_SERIAL	/* Serial port console */
+#endif
+
+/* Console types supported only on BIOS platforms */
+#if defined ( PLATFORM_pcbios )
+  //#define CONSOLE_INT13	/* INT13 disk log console */
+  #define CONSOLE_PCBIOS	/* Default BIOS console */
+#endif
+
+/* Console types supported only on EFI platforms */
+#if defined ( PLATFORM_efi )
+  #define CONSOLE_EFI		/* Default EFI console */
+#endif
+
+/* Console types supported only on RISC-V SBI platforms */
+#if defined ( PLATFORM_sbi )
+  #define CONSOLE_SBI		/* RISC-V SBI debug console */
+#endif
+
+/* Console types supported only on Linux platforms */
+#if defined ( PLATFORM_linux )
+  #define CONSOLE_LINUX		/* Default Linux console */
+#endif
+
+/* Console types supported only on x86 CPUs */
+#if defined ( __i386__ ) || defined ( __x86_64__ )
+  //#define CONSOLE_DEBUGCON	/* Bochs/QEMU/KVM debug port console */
+  //#define CONSOLE_DIRECT_VGA	/* Direct access to VGA card */
+  //#define CONSOLE_PC_KBD	/* Direct access to PC keyboard */
+  //#define CONSOLE_VMWARE	/* VMware logfile console */
+#endif
+
+/* Enable serial console on platforms that are typically headless */
+#if defined ( CONSOLE_SBI )
+  #define CONSOLE_SERIAL
+#endif
+
+/*****************************************************************************
  *
- * You almost certainly do not need to enable these.
+ * Keyboard maps
+ *
+ * See hci/keymap/keymap_*.c for available keyboard maps.
  *
  */
 
-//#define	CONSOLE_DIRECT_VGA	/* Direct access to VGA card */
-//#define	CONSOLE_PC_KBD		/* Direct access to PC keyboard */
+#define KEYBOARD_MAP	us	/* Default US keyboard map */
+//#define KEYBOARD_MAP	dynamic	/* Runtime selectable keyboard map */
 
-/* Keyboard map (available maps in hci/keymap/) */
-#define	KEYBOARD_MAP	us
-
-/* Control which syslog() messages are generated.
+/*****************************************************************************
+ *
+ * Log levels
+ *
+ * Control which syslog() messages are generated.  Note that this is
+ * not related in any way to CONSOLE_SYSLOG.
  *
- * Note that this is not related in any way to CONSOLE_SYSLOG.
  */
+
 #define LOG_LEVEL	LOG_NONE
 
 #include <config/named.h>

src/config/defaults/efi.h

@@ -14,7 +14,6 @@ FILE_SECBOOT ( PERMITTED );
 #define IOMAP_VIRT
 #define PCIAPI_EFI
 #define DMAAPI_OP
-#define CONSOLE_EFI
 #define TIMER_EFI
 #define UMALLOC_EFI
 #define MEMMAP_NULL

src/config/defaults/linux.h

@@ -9,7 +9,6 @@
 
 FILE_LICENCE ( GPL2_OR_LATER );
 
-#define CONSOLE_LINUX
 #define TIMER_LINUX
 #define UACCESS_LINUX
 #define UMALLOC_LINUX

src/config/defaults/pcbios.h

@@ -14,7 +14,6 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 #define PCIAPI_PCBIOS
 #define DMAAPI_FLAT
 #define TIMER_PCBIOS
-#define CONSOLE_PCBIOS
 #define NAP_PCBIOS
 #define UMALLOC_UHEAP
 #define MEMMAP_INT15

src/config/defaults/sbi.h

@@ -23,8 +23,6 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 #endif
 
 #define FDT_SBI
-#define CONSOLE_SBI
-#define CONSOLE_SERIAL
 #define REBOOT_SBI
 #define UMALLOC_UHEAP
 #define MEMMAP_FDT