Initial import

1 files changed, 196 insertions, 0 deletions

diff --git a/arch/frv/mb93090-mb00/pci-frv.c b/arch/frv/mb93090-mb00/pci-frv.c
new file mode 100644
index 000000000..0635bd6c2
--- /dev/null
+++ b/arch/frv/mb93090-mb00/pci-frv.c
@@ -0,0 +1,196 @@
+/* pci-frv.c: low-level PCI access routines
+ *
+ * Copyright (C) 2003-5 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * - Derived from the i386 equivalent stuff
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+
+#include "pci-frv.h"
+
+/*
+ * We need to avoid collisions with `mirrored' VGA ports
+ * and other strange ISA hardware, so we always want the
+ * addresses to be allocated in the 0x000-0x0ff region
+ * modulo 0x400.
+ *
+ * Why? Because some silly external IO cards only decode
+ * the low 10 bits of the IO address. The 0x00-0xff region
+ * is reserved for motherboard devices that decode all 16
+ * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
+ * but we want to try to avoid allocating at 0x2900-0x2bff
+ * which might have be mirrored at 0x0100-0x03ff..
+ */
+resource_size_t
+pcibios_align_resource(void *data, const struct resource *res,
+		       resource_size_t size, resource_size_t align)
+{
+	resource_size_t start = res->start;
+
+	if ((res->flags & IORESOURCE_IO) && (start & 0x300))
+		start = (start + 0x3ff) & ~0x3ff;
+
+	return start;
+}
+
+
+/*
+ *  Handle resources of PCI devices.  If the world were perfect, we could
+ *  just allocate all the resource regions and do nothing more.  It isn't.
+ *  On the other hand, we cannot just re-allocate all devices, as it would
+ *  require us to know lots of host bridge internals.  So we attempt to
+ *  keep as much of the original configuration as possible, but tweak it
+ *  when it's found to be wrong.
+ *
+ *  Known BIOS problems we have to work around:
+ *	- I/O or memory regions not configured
+ *	- regions configured, but not enabled in the command register
+ *	- bogus I/O addresses above 64K used
+ *	- expansion ROMs left enabled (this may sound harmless, but given
+ *	  the fact the PCI specs explicitly allow address decoders to be
+ *	  shared between expansion ROMs and other resource regions, it's
+ *	  at least dangerous)
+ *
+ *  Our solution:
+ *	(1) Allocate resources for all buses behind PCI-to-PCI bridges.
+ *	    This gives us fixed barriers on where we can allocate.
+ *	(2) Allocate resources for all enabled devices.  If there is
+ *	    a collision, just mark the resource as unallocated. Also
+ *	    disable expansion ROMs during this step.
+ *	(3) Try to allocate resources for disabled devices.  If the
+ *	    resources were assigned correctly, everything goes well,
+ *	    if they weren't, they won't disturb allocation of other
+ *	    resources.
+ *	(4) Assign new addresses to resources which were either
+ *	    not configured at all or misconfigured.  If explicitly
+ *	    requested by the user, configure expansion ROM address
+ *	    as well.
+ */
+
+static void __init pcibios_allocate_bus_resources(struct list_head *bus_list)
+{
+	struct list_head *ln;
+	struct pci_bus *bus;
+	struct pci_dev *dev;
+	int idx;
+	struct resource *r;
+
+	/* Depth-First Search on bus tree */
+	for (ln=bus_list->next; ln != bus_list; ln=ln->next) {
+		bus = list_entry(ln, struct pci_bus, node);
+		if ((dev = bus->self)) {
+			for (idx = PCI_BRIDGE_RESOURCES; idx < PCI_NUM_RESOURCES; idx++) {
+				r = &dev->resource[idx];
+				if (!r->start)
+					continue;
+				pci_claim_bridge_resource(dev, idx);
+			}
+		}
+		pcibios_allocate_bus_resources(&bus->children);
+	}
+}
+
+static void __init pcibios_allocate_resources(int pass)
+{
+	struct pci_dev *dev = NULL;
+	int idx, disabled;
+	u16 command;
+	struct resource *r;
+
+	for_each_pci_dev(dev) {
+		pci_read_config_word(dev, PCI_COMMAND, &command);
+		for(idx = 0; idx < 6; idx++) {
+			r = &dev->resource[idx];
+			if (r->parent)		/* Already allocated */
+				continue;
+			if (!r->start)		/* Address not assigned at all */
+				continue;
+			if (r->flags & IORESOURCE_IO)
+				disabled = !(command & PCI_COMMAND_IO);
+			else
+				disabled = !(command & PCI_COMMAND_MEMORY);
+			if (pass == disabled) {
+				DBG("PCI: Resource %08lx-%08lx (f=%lx, d=%d, p=%d)\n",
+				    r->start, r->end, r->flags, disabled, pass);
+				if (pci_claim_resource(dev, idx) < 0) {
+					/* We'll assign a new address later */
+					r->end -= r->start;
+					r->start = 0;
+				}
+			}
+		}
+		if (!pass) {
+			r = &dev->resource[PCI_ROM_RESOURCE];
+			if (r->flags & IORESOURCE_ROM_ENABLE) {
+				/* Turn the ROM off, leave the resource region, but keep it unregistered. */
+				u32 reg;
+				DBG("PCI: Switching off ROM of %s\n", pci_name(dev));
+				r->flags &= ~IORESOURCE_ROM_ENABLE;
+				pci_read_config_dword(dev, dev->rom_base_reg, &reg);
+				pci_write_config_dword(dev, dev->rom_base_reg, reg & ~PCI_ROM_ADDRESS_ENABLE);
+			}
+		}
+	}
+}
+
+static void __init pcibios_assign_resources(void)
+{
+	struct pci_dev *dev = NULL;
+	int idx;
+	struct resource *r;
+
+	for_each_pci_dev(dev) {
+		int class = dev->class >> 8;
+
+		/* Don't touch classless devices and host bridges */
+		if (!class || class == PCI_CLASS_BRIDGE_HOST)
+			continue;
+
+		for(idx=0; idx<6; idx++) {
+			r = &dev->resource[idx];
+
+			/*
+			 *  Don't touch IDE controllers and I/O ports of video cards!
+			 */
+			if ((class == PCI_CLASS_STORAGE_IDE && idx < 4) ||
+			    (class == PCI_CLASS_DISPLAY_VGA && (r->flags & IORESOURCE_IO)))
+				continue;
+
+			/*
+			 *  We shall assign a new address to this resource, either because
+			 *  the BIOS forgot to do so or because we have decided the old
+			 *  address was unusable for some reason.
+			 */
+			if (!r->start && r->end)
+				pci_assign_resource(dev, idx);
+		}
+
+		if (pci_probe & PCI_ASSIGN_ROMS) {
+			r = &dev->resource[PCI_ROM_RESOURCE];
+			r->end -= r->start;
+			r->start = 0;
+			if (r->end)
+				pci_assign_resource(dev, PCI_ROM_RESOURCE);
+		}
+	}
+}
+
+void __init pcibios_resource_survey(void)
+{
+	DBG("PCI: Allocating resources\n");
+	pcibios_allocate_bus_resources(&pci_root_buses);
+	pcibios_allocate_resources(0);
+	pcibios_allocate_resources(1);
+	pcibios_assign_resources();
+}