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, 31 insertions, 0 deletions

diff --git a/include/asm-alpha/vga.h b/include/asm-alpha/vga.h
index ed06f59b544d..e8df1e7aae6b 100644
--- a/include/asm-alpha/vga.h
+++ b/include/asm-alpha/vga.h
@@ -46,6 +46,37 @@ extern void scr_memcpyw(u16 *d, const u16 *s, unsigned int count);
 #define vga_readb(a)	readb((u8 __iomem *)(a))
 #define vga_writeb(v,a)	writeb(v, (u8 __iomem *)(a))
 
+#ifdef CONFIG_VGA_HOSE
+#include <linux/ioport.h>
+#include <linux/pci.h>
+
+extern struct pci_controller *pci_vga_hose;
+
+# define __is_port_vga(a)       \
+	(((a) >= 0x3b0) && ((a) < 0x3e0) && \
+	 ((a) != 0x3b3) && ((a) != 0x3d3))
+
+# define __is_mem_vga(a) \
+	(((a) >= 0xa0000) && ((a) <= 0xc0000))
+
+# define FIXUP_IOADDR_VGA(a) do {                       \
+	if (pci_vga_hose && __is_port_vga(a))     \
+		(a) += pci_vga_hose->io_space->start;	  \
+ } while(0)
+
+# define FIXUP_MEMADDR_VGA(a) do {                       \
+	if (pci_vga_hose && __is_mem_vga(a))     \
+		(a) += pci_vga_hose->mem_space->start; \
+ } while(0)
+
+#else /* CONFIG_VGA_HOSE */
+# define pci_vga_hose 0
+# define __is_port_vga(a) 0
+# define __is_mem_vga(a) 0
+# define FIXUP_IOADDR_VGA(a)
+# define FIXUP_MEMADDR_VGA(a)
+#endif /* CONFIG_VGA_HOSE */
+
 #define VGA_MAP_MEM(x,s)	((unsigned long) ioremap(x, s))
 
 #endif