payloads: Reorganize Kconfig for external payloads

The integration of external payloads in coreboot
is a bit messy. You have to change the to level Kconfig
file for every payload (something that we recently fixed
for mainboards and chipsets). This means that updating
e.g. the SeaBIOS version requires a change outside of the
SeaBIOS directory.

With this patch you can create a new directory under
payloads/external and place a Kconfig and Kconfig.name
file in there, and the payload will automatically show
up when you do "make menuconfig".

Change-Id: I293abcb8eae581d4b3934e64897c0d339a27e7c1
Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-on: http://review.coreboot.org/10828
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

payloads/external/SeaBIOS/Kconfig

@@ -0,0 +1,70 @@
+if PAYLOAD_SEABIOS
+
+choice
+	prompt "SeaBIOS version"
+	default SEABIOS_STABLE
+
+config SEABIOS_STABLE
+	bool "1.7.5"
+	help
+	  Stable SeaBIOS version
+config SEABIOS_MASTER
+	bool "master"
+	help
+	  Newest SeaBIOS version
+
+endchoice
+
+config SEABIOS_PS2_TIMEOUT
+	prompt "PS/2 keyboard controller initialization timeout (milliseconds)"
+	default 0
+	depends on EXPERT
+	int
+	help
+	  Some PS/2 keyboard controllers don't respond to commands immediately
+	  after powering on. This specifies how long SeaBIOS will wait for the
+	  keyboard controller to become ready before giving up.
+
+config SEABIOS_THREAD_OPTIONROMS
+	prompt "Hardware init during option ROM execution"
+	default n
+	bool
+	help
+	  Allow hardware init to run in parallel with optionrom execution.
+
+	  This can reduce boot time, but can cause some timing
+	  variations during option ROM code execution. It is not
+	  known if all option ROMs will behave properly with this option.
+
+config SEABIOS_MALLOC_UPPERMEMORY
+	bool
+	default y
+	help
+	  Use the "Upper Memory Block" area (0xc0000-0xf0000) for internal
+	  "low memory" allocations.  If this is not selected, the memory is
+	  instead allocated from the "9-segment" (0x90000-0xa0000).
+	  This is not typically needed, but may be required on some platforms
+	  to allow USB and SATA buffers to be written correctly by the
+	  hardware.  In general, if this is desired, the option will be
+	  set to 'N' by the chipset Kconfig.
+
+config SEABIOS_VGA_COREBOOT
+	prompt "Include generated option rom that implements legacy VGA BIOS compatibility"
+	default n
+	depends on !VGA_BIOS && (MAINBOARD_DO_NATIVE_VGA_INIT || MAINBOARD_HAS_NATIVE_VGA_INIT_TEXTMODECFG)
+	bool
+	help
+	  Coreboot can initialize the GPU of some mainboards.
+	  
+	  After initializing the GPU, the information about it can be passed to the payload.
+	  Provide an option rom that implements this legacy VGA BIOS compatibility requirement.
+
+config PAYLOAD_FILE
+	default "payloads/external/SeaBIOS/seabios/out/bios.bin.elf"
+
+config PAYLOAD_VGABIOS_FILE
+	string
+	depends on SEABIOS_VGA_COREBOOT
+	default "payloads/external/SeaBIOS/seabios/out/vgabios.bin"
+
+endif

payloads/external/SeaBIOS/Kconfig.name

@@ -0,0 +1,9 @@
+config PAYLOAD_SEABIOS
+	bool "SeaBIOS"
+	depends on ARCH_X86
+	help
+	  Select this option if you want to build a coreboot image
+	  with a SeaBIOS payload. If you don't know what this is
+	  about, just leave it enabled.
+
+	  See http://coreboot.org/Payloads for more information.