ALPHA: support graphics on non-zero PCI domains

This code replaces earlier and incomplete handling of graphics on non-zero PCI
domains (aka hoses or peer PCI buses).

An option (CONFIG_VGA_HOSE) is set TRUE if configuring a GENERIC kernel, or a
kernel for MARVEL, TITAN, or TSUNAMI machines, as these are the machines whose
SRM consoles are capable of configuring and handling graphics options on
non-zero hoses.  All other machines have the option set FALSE.

A routine, "find_console_vga_hose()", is used to find the graphics device
which the machine's firmware believes is the console device, and it sets a
global (pci_vga_hose) for later use in managing access to the device.  This is
called in "init_arch" on TITAN and TSUNAMI machines; MARVEL machines use a
custom version of this routine because of extra complexity.

A routine, "locate_and_init_vga()", is used to find the graphics device and
set a global (pci_vga_hose) for later use in managing access to the device, in
the case where "find_console_vga_hose" has failed.

Various adjustments are made to the ioremap and ioportmap routines for
detecting and translating "legacy" VGA register and memory references to the
real PCI domain.

[akpm@linux-foundation.org: don't statically init bss]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Jay Estabrook <jay.estabrook@hp.com>
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/alpha/kernel/sys_dp264.c b/arch/alpha/kernel/sys_dp264.c
index 85d2f93..c71b0fd 100644
--- a/arch/alpha/kernel/sys_dp264.c
+++ b/arch/alpha/kernel/sys_dp264.c
@@ -543,6 +543,7 @@
 {
 	common_init_pci();
 	SMC669_Init(0);
+	locate_and_init_vga(NULL);
 }
 
 static void __init
@@ -551,6 +552,14 @@
 	common_init_pci();
 	SMC669_Init(1);
 	es1888_init();
+	locate_and_init_vga(NULL);
+}
+
+static void __init
+clipper_init_pci(void)
+{
+	common_init_pci();
+	locate_and_init_vga(NULL);
 }
 
 static void __init
@@ -655,7 +664,7 @@
 	.init_arch		= tsunami_init_arch,
 	.init_irq		= clipper_init_irq,
 	.init_rtc		= common_init_rtc,
-	.init_pci		= common_init_pci,
+	.init_pci		= clipper_init_pci,
 	.kill_arch		= tsunami_kill_arch,
 	.pci_map_irq		= clipper_map_irq,
 	.pci_swizzle		= common_swizzle,