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>

1 files changed, 16 insertions, 0 deletions

diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index 770f717bd250..905e86408aaa 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -481,6 +481,15 @@ config ALPHA_BROKEN_IRQ_MASK
         depends on ALPHA_GENERIC || ALPHA_PC164
         default y
 
+config VGA_HOSE
+        bool
+        depends on ALPHA_GENERIC || ALPHA_TITAN || ALPHA_MARVEL || ALPHA_TSUNAMI
+        default y
+        help
+          Support VGA on an arbitrary hose; needed for several platforms
+          which always have multiple hoses, and whose consoles support it.
+
+
 config ALPHA_SRM
         bool "Use SRM as bootloader" if ALPHA_CABRIOLET || ALPHA_AVANTI_CH || ALPHA_EB64P || ALPHA_PC164 || ALPHA_TAKARA || ALPHA_EB164 || ALPHA_ALCOR || ALPHA_MIATA || ALPHA_LX164 || ALPHA_SX164 || ALPHA_NAUTILUS || ALPHA_NONAME
         default y if ALPHA_JENSEN || ALPHA_MIKASA || ALPHA_SABLE || ALPHA_LYNX || ALPHA_NORITAKE || ALPHA_DP264 || ALPHA_RAWHIDE || ALPHA_EIGER || ALPHA_WILDFIRE || ALPHA_TITAN || ALPHA_SHARK || ALPHA_MARVEL
@@ -644,6 +653,13 @@ source "arch/alpha/oprofile/Kconfig"
 
 source "arch/alpha/Kconfig.debug"
 
+# DUMMY_CONSOLE may be defined in drivers/video/console/Kconfig
+# but we also need it if VGA_HOSE is set
+config DUMMY_CONSOLE
+        bool
+        depends on VGA_HOSE
+        default y
+
 source "security/Kconfig"
 
 source "crypto/Kconfig"