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>

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"

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)
@@ -29,37 +33,59 @@ default_vga_hose_select(struct pci_controller *h1, struct pci_controller *h2)
 	return h1;
 }
 
-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

arch/alpha/kernel/core_marvel.c

@@ -25,6 +25,7 @@
 #include <asm/pgalloc.h>
 #include <asm/tlbflush.h>
 #include <asm/rtc.h>
+#include <asm/vga.h>
 
 #include "proto.h"
 #include "pci_impl.h"
@@ -367,9 +368,8 @@ marvel_io7_present(gct6_node *node)
 }
 
 static void __init
-marvel_init_vga_hose(void)
+marvel_find_console_vga_hose(void)
 {
-#ifdef CONFIG_VGA_HOSE
 	u64 *pu64 = (u64 *)((u64)hwrpb + hwrpb->ctbt_offset);
 
 	if (pu64[7] == 3) {	/* TERM_TYPE == graphics */
@@ -403,7 +403,6 @@ marvel_init_vga_hose(void)
 			pci_vga_hose = hose;
 		}
 	}
-#endif /* CONFIG_VGA_HOSE */
 }
 
 gct6_search_struct gct_wanted_node_list[] = {
@@ -459,7 +458,7 @@ marvel_init_arch(void)
 		marvel_init_io7(io7);
 
 	/* Check for graphic console location (if any).  */
-	marvel_init_vga_hose();
+	marvel_find_console_vga_hose();
 }
 
 void
@@ -684,9 +683,6 @@ __marvel_rtc_io(u8 b, unsigned long addr, int write)
 /*
  * IO map support.
  */
-
-#define __marvel_is_mem_vga(a)	(((a) >= 0xa0000) && ((a) <= 0xc0000))
-
 void __iomem *
 marvel_ioremap(unsigned long addr, unsigned long size)
 {
@@ -698,13 +694,9 @@ marvel_ioremap(unsigned long addr, unsigned long size)
 	unsigned long pfn;
 
 	/*
-	 * Adjust the addr.
+	 * Adjust the address.
 	 */ 
-#ifdef CONFIG_VGA_HOSE
-	if (pci_vga_hose && __marvel_is_mem_vga(addr)) {
-		addr += pci_vga_hose->mem_space->start;
-	}
-#endif
+	FIXUP_MEMADDR_VGA(addr);
 
 	/*
 	 * Find the hose.
@@ -781,7 +773,9 @@ marvel_ioremap(unsigned long addr, unsigned long size)
 		return (void __iomem *) vaddr;
 	}
 
-	return NULL;
+	/* Assume it was already a reasonable address */
+	vaddr = baddr + hose->mem_space->start;
+	return (void __iomem *) vaddr;
 }
 
 void
@@ -803,21 +797,12 @@ marvel_is_mmio(const volatile void __iomem *xaddr)
 		return (addr & 0xFF000000UL) == 0;
 }
 
-#define __marvel_is_port_vga(a)	\
-  (((a) >= 0x3b0) && ((a) < 0x3e0) && ((a) != 0x3b3) && ((a) != 0x3d3))
 #define __marvel_is_port_kbd(a)	(((a) == 0x60) || ((a) == 0x64))
 #define __marvel_is_port_rtc(a)	(((a) == 0x70) || ((a) == 0x71))
 
 void __iomem *marvel_ioportmap (unsigned long addr)
 {
-	if (__marvel_is_port_rtc (addr) || __marvel_is_port_kbd(addr))
-		;
-#ifdef CONFIG_VGA_HOSE
-	else if (__marvel_is_port_vga (addr) && pci_vga_hose)
-		addr += pci_vga_hose->io_space->start;
-#endif
-	else
-		return NULL;
+	FIXUP_IOADDR_VGA(addr);
 	return (void __iomem *)addr;
 }
 
@@ -829,8 +814,14 @@ marvel_ioread8(void __iomem *xaddr)
 		return 0;
 	else if (__marvel_is_port_rtc(addr))
 		return __marvel_rtc_io(0, addr, 0);
-	else
+	else if (marvel_is_ioaddr(addr))
 		return __kernel_ldbu(*(vucp)addr);
+	else
+		/* this should catch other legacy addresses
+		   that would normally fail on MARVEL,
+		   because there really is nothing there...
+		*/
+		return ~0;
 }
 
 void
@@ -841,7 +832,7 @@ marvel_iowrite8(u8 b, void __iomem *xaddr)
 		return;
 	else if (__marvel_is_port_rtc(addr)) 
 		__marvel_rtc_io(b, addr, 1);
-	else
+	else if (marvel_is_ioaddr(addr))
 		__kernel_stb(b, *(vucp)addr);
 }