[build] Allow ISA ROMs to be built

The build process has for a long time assumed that every ROM is a PCI
ROM, and will always include the PCI header and PCI-related
functionality (such as checking the PCI BIOS version, including the
PCI bus:dev.fn address within the ROM product name string, etc.).

While real ISA cards are no longer in use, some virtualisation
environments (notably VirtualBox) have support only for ISA ROMs.
This can cause problems: in particular, VirtualBox will call our
initialisation entry point with random garbage in %ax, which we then
treat as the PCI bus:dev.fn address of the autoboot device: this
generally prevents the default boot sequence from using any network
devices.

Create .isarom and .pcirom prefixes which can be used to explicitly
specify the type of ROM to be created.  (Note that the .mrom prefix
always implies a PCI ROM, since the .mrom mechanism relies on
reconfiguring PCI BARs.)

Make .rom a magic prefix which will automatically select the
appropriate PCI or ISA ROM prefix for ROMs defined via a PCI_ROM() or
ISA_ROM() macro.  To maintain backwards compatibility, we default to
building a PCI ROM for anything which is not directly derived from a
PCI_ROM() or ISA_ROM() macro (e.g. bin/intel.rom).

Add a selection of targets to "make everything" to ensure that the
(relatively obscure) ISA ROM build process is included within the
per-commit QA checks.

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

src/Makefile

 #
 everything :
 	$(Q)$(MAKE) --no-print-directory $(ALL) \
+		bin/3c509.rom bin/intel.rom bin/intel.mrom \
 		bin-i386-efi/ipxe.efi bin-i386-efi/ipxe.efidrv \
 		bin-i386-efi/ipxe.efirom \
 		bin-x86_64-efi/ipxe.efi bin-x86_64-efi/ipxe.efidrv \

src/Makefile.housekeeping

 # derive the variables:
 # 
 # TGT_ELEMENTS : the elements of the target (e.g. "dfe538 prism2_pci")
-# TGT_PREFIX   : the prefix type (e.g. "rom")
+# TGT_PREFIX   : the prefix type (e.g. "pcirom")
 # TGT_DRIVERS  : the driver for each element (e.g. "rtl8139 prism2_pci")
 # TGT_ROM_NAME : the ROM name (e.g. "dfe538")
 #
 DRIVERS_ipxe	= $(DRIVERS)
 CARD_DRIVER	= $(firstword $(DRIVER_$(1)) $(1))
 TGT_ELEMENTS	= $(subst --, ,$(firstword $(subst ., ,$(notdir $@))))
-TGT_PREFIX	= $(word 2,$(subst ., ,$(notdir $@)))
 TGT_ROM_NAME	= $(firstword $(TGT_ELEMENTS))
 TGT_DRIVERS	= $(strip $(if $(DRIVERS_$(TGT_ROM_NAME)), \
 			       $(DRIVERS_$(TGT_ROM_NAME)), \
 			       $(foreach TGT_ELEMENT,$(TGT_ELEMENTS), \
 			         $(call CARD_DRIVER,$(TGT_ELEMENT))) ))
+TGT_PREFIX_NAME	= $(word 2,$(subst ., ,$(notdir $@)))
+TGT_PREFIX	= $(strip $(if $(filter rom,$(TGT_PREFIX_NAME)), \
+			       $(ROM_TYPE_$(TGT_ROM_NAME))rom, \
+			       $(TGT_PREFIX_NAME)))
 
 # Look up ROM IDs for the current target
 # (e.g. "bin/dfe538--prism2_pci.rom.tmp") and derive the variables:

src/arch/i386/Makefile.pcbios

 #
 MEDIA		+= rom
 MEDIA		+= mrom
+MEDIA		+= pcirom
+MEDIA		+= isarom
 MEDIA		+= pxe
 MEDIA		+= kpxe
 MEDIA		+= kkpxe
 #
 PAD_rom		= $(PERL) $(PADIMG) --blksize=512 --byte=0xff
 PAD_mrom	= $(PAD_rom)
+PAD_pcirom	= $(PAD_rom)
+PAD_isarom	= $(PAD_rom)
 PAD_dsk		= $(PERL) $(PADIMG) --blksize=512
 PAD_hd		= $(PERL) $(PADIMG) --blksize=32768
 PAD_exe		= $(PERL) $(PADIMG) --blksize=512
 #
 FINALISE_rom	= $(PERL) $(FIXROM)
 FINALISE_mrom	= $(FINALISE_rom)
+FINALISE_pcirom	= $(FINALISE_rom)
+FINALISE_isarom	= $(FINALISE_rom)
 
-# Use $(ROMS) rather than $(DRIVERS) for "allroms" and "allmroms"
+# Use $(ROMS) rather than $(DRIVERS) for "allroms", "allmroms", etc.
 #
 LIST_NAME_rom := ROMS
 LIST_NAME_mrom := ROMS
+LIST_NAME_pcirom := ROMS
+LIST_NAME_isarom := ROMS
 
 # rule to make a non-emulation ISO boot image
 NON_AUTO_MEDIA	+= iso

src/arch/i386/prefix/isaromprefix.S

+/*
+ * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER )
+
+#define BUSTYPE "ISAR"
+#define _rom_start _isarom_start
+#include "romprefix.S"

src/arch/i386/prefix/libprefix.S

 	ret
 	.size	print_character, . - print_character
 
+/*****************************************************************************
+ * Utility function: print space
+ *
+ * Parameters:
+ *   %ds:di : output buffer (or %di=0 to print to console)
+ * Returns:
+ *   %ds:di : next character in output buffer (if applicable)
+ *****************************************************************************
+ */
+	.section ".prefix.lib", "awx", @progbits
+	.code16
+	.globl	print_space
+print_space:
+	/* Preserve registers */
+	pushw	%ax
+	/* Print space */
+	movb	$( ' ' ), %al
+	call	print_character
+	/* Restore registers and return */
+	popw	%ax
+	ret
+	.size	print_space, . - print_space
+
 /*****************************************************************************
  * Utility function: print a NUL-terminated string
  *
 	movb	$( '\r' ), %al
 	call	print_character
 	/* Print 79 spaces */
-	movb	$( ' ' ), %al
 	movw	$79, %cx
-1:	call	print_character
+1:	call	print_space
 	loop	1b
 	/* Print CR */
-	movb	$( '\r' ), %al
 	call	print_character
 	/* Restore registers and return */
 	popw	%cx

src/arch/i386/prefix/mromprefix.S

 
 #define ROMPREFIX_EXCLUDE_PAYLOAD 1
 #define ROMPREFIX_MORE_IMAGES 1
-#define _rom_start _mrom_start
-#include "romprefix.S"
+#define _pcirom_start _mrom_start
+#include "pciromprefix.S"
 
 	.text
 	.arch i386

src/arch/i386/prefix/pciromprefix.S

+/*
+ * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER )
+
+#define BUSTYPE "PCIR"
+#define _rom_start _pcirom_start
+#include "romprefix.S"

src/arch/i386/prefix/romprefix.S

 #define INDICATOR 0x00
 #else
 #define INDICATOR 0x80
+#endif
+
+/* Default to building a PCI ROM if no bus type is specified
+ */
+#ifndef BUSTYPE
+#define BUSTYPE "PCIR"
 #endif
 
 	.text
 	.word	ipxeheader
 	.org	0x16
 	.word	undiheader
+.ifeqs	BUSTYPE, "PCIR"
 	.org	0x18
 	.word	pciheader
+.endif
 	.org	0x1a
 	.word	pnpheader
 	.size romheader, . - romheader
 	.long	0
 	.previous
 
+.ifeqs	BUSTYPE, "PCIR"
 pciheader:
 	.ascii	"PCIR"			/* Signature */
 	.word	pci_vendor_id		/* Vendor identification */ 
 	.long	512
 	.long	0
 	.previous
+.endif	/* PCIR */
 
 	/* PnP doesn't require any particular alignment, but IBM
 	 * BIOSes will scan on 16-byte boundaries rather than using
  */
 prodstr:
 	.ascii	PRODUCT_SHORT_NAME
+.ifeqs	BUSTYPE, "PCIR"
 prodstr_separator:
 	.byte	0
 	.ascii	"(PCI "
 prodstr_pci_id:
-	.asciz	"xx:xx.x)"		/* Filled in by init code */
+	.ascii	"xx:xx.x)"		/* Filled in by init code */
+.endif	/* PCIR */
+	.byte	0
 	.size prodstr, . - prodstr
 
 	.globl	undiheader	
 	.word	_data16_memsz		/* Stack segment size */
 	.word	_data16_memsz		/* Data segment size */
 	.word	_text16_memsz		/* Code segment size */
-	.ascii	"PCIR"			/* Bus type */
+	.ascii	BUSTYPE			/* Bus type */
 	.equ undiheader_len, . - undiheader
 	.size undiheader, . - undiheader
 
 	pushw	%cs
 	popw	%ds
 
-	/* Store PCI 3.0 runtime segment address for later use */
-	movw	%bx, %gs
-
-	/* Store PCI bus:dev.fn address */
-	movw	%ax, init_pci_busdevfn
-
 	/* Print message as early as possible */
 	movw	$init_message, %si
 	xorw	%di, %di
 	call	print_message
-	call	print_pci_busdevfn
 
-	/* Fill in product name string, if possible */
+	/* Store PCI 3.0 runtime segment address for later use, if
+	 * applicable.
+	 */
+.ifeqs	BUSTYPE, "PCIR"
+	movw	%bx, %gs
+.endif
+
+	/* Store PCI bus:dev.fn address, print PCI bus:dev.fn, and add
+	 * PCI bus:dev.fn to product name string, if applicable.
+	 */
+.ifeqs	BUSTYPE, "PCIR"
+	xorw	%di, %di
+	call	print_space
+	movw	%ax, init_pci_busdevfn
+	call	print_pci_busdevfn
 	movw	$prodstr_pci_id, %di
 	call	print_pci_busdevfn
 	movb	$( ' ' ), prodstr_separator
+.endif
 
 	/* Print segment address */
-	movb	$( ' ' ), %al
 	xorw	%di, %di
-	call	print_character
+	call	print_space
 	movw	%cs, %ax
 	call	print_hex_word
 
-	/* Check for PCI BIOS version */
+	/* Check for PCI BIOS version, if applicable */
+.ifeqs	BUSTYPE, "PCIR"
 	pushl	%ebx
 	pushl	%edx
 	pushl	%edi
 1:	popl	%edi
 	popl	%edx
 	popl	%ebx
+.endif	/* PCIR */
 
 	/* Check for PnP BIOS.  Although %es:di should point to the
 	 * PnP BIOS signature on entry, some BIOSes fail to do this.
 	loop	1b
 	subb	%bl, checksum
 
-	/* Copy self to option ROM space.  Required for PCI3.0, which
-	 * loads us to a temporary location in low memory.  Will be a
-	 * no-op for lower PCI versions.
+	/* Copy self to option ROM space, if applicable.  Required for
+	 * PCI3.0, which loads us to a temporary location in low
+	 * memory.  Will be a no-op for lower PCI versions.
 	 */
-	movb	$( ' ' ), %al
+.ifeqs	BUSTYPE, "PCIR"
 	xorw	%di, %di
-	call	print_character
+	call	print_space
 	movw	%gs, %ax
 	call	print_hex_word
 	movzbw	romheader_size, %cx
 	xorw	%si, %si
 	xorw	%di, %di
 	cs rep	movsb
+.endif
 
-	/* Skip prompt if this is not the first PCI function */
+	/* Skip prompt if this is not the first PCI function, if applicable */
+.ifeqs	BUSTYPE, "PCIR"
 	testb	$PCI_FUNC_MASK, init_pci_busdevfn
 	jnz	no_shell
+.endif
 	/* Prompt for POST-time shell */
 	movw	$init_message_prompt, %si
 	xorw	%di, %di
 	.ascii	"\n"
 	.ascii	PRODUCT_NAME
 	.ascii	"\n"
-	.asciz	"iPXE (http://ipxe.org) "
+	.asciz	"iPXE (http://ipxe.org)"
 	.size	init_message, . - init_message
+.ifeqs	BUSTYPE, "PCIR"
 init_message_pci:
 	.asciz	" PCI"
 	.size	init_message_pci, . - init_message_pci
+.endif	/* PCIR */
 init_message_pnp:
 	.asciz	" PnP"
 	.size	init_message_pnp, . - init_message_pnp
 /* PCI bus:dev.fn
  *
  */
+.ifeqs	BUSTYPE, "PCIR"
 init_pci_busdevfn:
 	.word	0
 	.size	init_pci_busdevfn, . - init_pci_busdevfn
+.endif	/* PCIR */
 
 /* Image source area
  *
 	lret
 	.section ".text16", "awx", @progbits
 1:
-	/* Retrieve PCI bus:dev.fn */
+	/* Retrieve PCI bus:dev.fn, if applicable */
+.ifeqs	BUSTYPE, "PCIR"
 	movw	init_pci_busdevfn, %ax
+.endif
 
 	/* Set up %ds for access to .data16 */
 	movw	%bx, %ds
 
-	/* Store PCI bus:dev.fn */
+	/* Store PCI bus:dev.fn, if applicable */
+.ifeqs	BUSTYPE, "PCIR"
 	movw	%ax, autoboot_busdevfn
+.endif
 
 	/* Call main() */
 	pushl	$main