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, 48 insertions, 22 deletions

diff --git a/arch/alpha/kernel/console.c b/arch/alpha/kernel/console.c
index f313b34939bb..da711e37fc97 100644
--- a/arch/alpha/kernel/console.c
+++ b/arch/alpha/kernel/console.c
@@ -9,16 +9,20 @@
 #include <linux/init.h>
 #include <linux/tty.h>
 #include <linux/console.h>
+#include <linux/vt.h>
 #include <asm/vga.h>
 #include <asm/machvec.h>
 
+#include "pci_impl.h"
+
 #ifdef CONFIG_VGA_HOSE
 
-/*
- * Externally-visible vga hose bases
- */
-unsigned long __vga_hose_io_base = 0;	/* base for default hose */
-unsigned long __vga_hose_mem_base = 0;	/* base for default hose */
+struct pci_controller *pci_vga_hose;
+static struct resource alpha_vga = {
+	.name	= "alpha-vga+",
+	.start	= 0x3C0,
+	.end	= 0x3DF
+};
 
 static struct pci_controller * __init 
 default_vga_hose_select(struct pci_controller *h1, struct pci_controller *h2)
@@ -30,36 +34,58 @@ default_vga_hose_select(struct pci_controller *h1, struct pci_controller *h2)
 }
 
 void __init 
-set_vga_hose(struct pci_controller *hose)
-{
-	if (hose) {
-		__vga_hose_io_base = hose->io_space->start;
-		__vga_hose_mem_base = hose->mem_space->start;
-	}
-}
-
-void __init 
 locate_and_init_vga(void *(*sel_func)(void *, void *))
 {
 	struct pci_controller *hose = NULL;
 	struct pci_dev *dev = NULL;
 
+	/* Default the select function */
 	if (!sel_func) sel_func = (void *)default_vga_hose_select;
 
+	/* Find the console VGA device */
 	for(dev=NULL; (dev=pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, dev));) {
-		if (!hose) hose = dev->sysdata;
-		else hose = sel_func(hose, dev->sysdata);
+		if (!hose)
+			hose = dev->sysdata;
+		else
+			hose = sel_func(hose, dev->sysdata);
 	}
 
-	/* Did we already inititialize the correct one? */
-	if (conswitchp == &vga_con &&
-	    __vga_hose_io_base == hose->io_space->start &&
-	    __vga_hose_mem_base == hose->mem_space->start)
+	/* Did we already initialize the correct one? Is there one? */
+	if (!hose || (conswitchp == &vga_con && pci_vga_hose == hose))
 		return;
 
-	/* Set the VGA hose and init the new console */
-	set_vga_hose(hose);
+	/* Create a new VGA ioport resource WRT the hose it is on. */
+	alpha_vga.start += hose->io_space->start;
+	alpha_vga.end += hose->io_space->start;
+	request_resource(hose->io_space, &alpha_vga);
+
+	/* Set the VGA hose and init the new console. */
+	pci_vga_hose = hose;
 	take_over_console(&vga_con, 0, MAX_NR_CONSOLES-1, 1);
 }
 
+void __init
+find_console_vga_hose(void)
+{
+	u64 *pu64 = (u64 *)((u64)hwrpb + hwrpb->ctbt_offset);
+
+	if (pu64[7] == 3) {	/* TERM_TYPE == graphics */
+		struct pci_controller *hose;
+		int h = (pu64[30] >> 24) & 0xff;	/* console hose # */
+
+		/*
+		 * Our hose numbering DOES match the console's, so find
+		 * the right one...
+		 */
+		for (hose = hose_head; hose; hose = hose->next) {
+			if (hose->index == h) break;
+		}
+
+		if (hose) {
+			printk("Console graphics on hose %d\n", h);
+			pci_vga_hose = hose;
+		}
+	}
+}
+
 #endif