1 files changed, 303 insertions, 0 deletions

diff --git a/arch/mn10300/unit-asb2305/pci-asb2305.c b/arch/mn10300/unit-asb2305/pci-asb2305.c
new file mode 100644
index 0000000..d100ca7
--- /dev/null
+++ b/arch/mn10300/unit-asb2305/pci-asb2305.c
@@ -0,0 +1,303 @@
+/* ASB2305 PCI resource stuff
+ *
+ * Copyright (C) 2001 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * - Derived from arch/i386/pci-i386.c
+ *   - Copyright 1997--2000 Martin Mares <mj@suse.cz>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, 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-asb2305.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..
+ */
+void pcibios_align_resource(void *data, struct resource *res,
+			    resource_size_t size, resource_size_t align)
+{
+#if 0
+	struct pci_dev *dev = data;
+
+	printk(KERN_DEBUG
+	       "### PCIBIOS_ALIGN_RESOURCE(%s,,{%08lx-%08lx,%08lx},%lx)\n",
+	       pci_name(dev),
+	       res->start,
+	       res->end,
+	       res->flags,
+	       size
+	       );
+#endif
+
+	if (res->flags & IORESOURCE_IO) {
+		unsigned long start = res->start;
+
+		if (start & 0x300) {
+			start = (start + 0x3ff) & ~0x3ff;
+			res->start = 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 pci_bus *bus;
+	struct pci_dev *dev;
+	int idx;
+	struct resource *r, *pr;
+
+	/* Depth-First Search on bus tree */
+	list_for_each_entry(bus, bus_list, node) {
+		dev = bus->self;
+		if (dev) {
+			for (idx = PCI_BRIDGE_RESOURCES;
+			     idx < PCI_NUM_RESOURCES;
+			     idx++) {
+				r = &dev->resource[idx];
+				if (!r->flags)
+					continue;
+				pr = pci_find_parent_resource(dev, r);
+				if (!r->start ||
+				    !pr ||
+				    request_resource(pr, r) < 0) {
+					printk(KERN_ERR "PCI:"
+					       " Cannot allocate resource"
+					       " region %d of bridge %s\n",
+					       idx, pci_name(dev));
+					/* Something is wrong with the region.
+					 * Invalidate the resource to prevent
+					 * child resource allocations in this
+					 * range. */
+					r->flags = 0;
+				}
+			}
+		}
+		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, *pr;
+
+	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 */
+				continue;
+			if (r->flags & IORESOURCE_IO)
+				disabled = !(command & PCI_COMMAND_IO);
+			else
+				disabled = !(command & PCI_COMMAND_MEMORY);
+			if (pass == disabled) {
+				DBG("PCI[%s]: Resource %08lx-%08lx"
+				    " (f=%lx, d=%d, p=%d)\n",
+				    pci_name(dev), r->start, r->end, r->flags,
+				    disabled, pass);
+				pr = pci_find_parent_resource(dev, r);
+				if (!pr || request_resource(pr, r) < 0) {
+					printk(KERN_ERR "PCI:"
+					       " Cannot allocate resource"
+					       " region %d of device %s\n",
+					       idx, pci_name(dev));
+					/* 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 int __init pcibios_assign_resources(void)
+{
+	struct pci_dev *dev = NULL;
+	struct resource *r, *pr;
+
+	if (!(pci_probe & PCI_ASSIGN_ROMS)) {
+		/* Try to use BIOS settings for ROMs, otherwise let
+		   pci_assign_unassigned_resources() allocate the new
+		   addresses. */
+		for_each_pci_dev(dev) {
+			r = &dev->resource[PCI_ROM_RESOURCE];
+			if (!r->flags || !r->start)
+				continue;
+			pr = pci_find_parent_resource(dev, r);
+			if (!pr || request_resource(pr, r) < 0) {
+				r->end -= r->start;
+				r->start = 0;
+			}
+		}
+	}
+
+	pci_assign_unassigned_resources();
+
+	return 0;
+}
+
+fs_initcall(pcibios_assign_resources);
+
+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);
+}
+
+int pcibios_enable_resources(struct pci_dev *dev, int mask)
+{
+	u16 cmd, old_cmd;
+	int idx;
+	struct resource *r;
+
+	pci_read_config_word(dev, PCI_COMMAND, &cmd);
+	old_cmd = cmd;
+
+	for (idx = 0; idx < 6; idx++) {
+		/* Only set up the requested stuff */
+		if (!(mask & (1 << idx)))
+			continue;
+
+		r = &dev->resource[idx];
+
+		if (!r->start && r->end) {
+			printk(KERN_ERR
+			       "PCI: Device %s not available because of"
+			       " resource collisions\n",
+			       pci_name(dev));
+			return -EINVAL;
+		}
+
+		if (r->flags & IORESOURCE_IO)
+			cmd |= PCI_COMMAND_IO;
+		if (r->flags & IORESOURCE_MEM)
+			cmd |= PCI_COMMAND_MEMORY;
+	}
+
+	if (dev->resource[PCI_ROM_RESOURCE].start)
+		cmd |= PCI_COMMAND_MEMORY;
+
+	if (cmd != old_cmd)
+		pci_write_config_word(dev, PCI_COMMAND, cmd);
+
+	return 0;
+}
+
+/*
+ *  If we set up a device for bus mastering, we need to check the latency
+ *  timer as certain crappy BIOSes forget to set it properly.
+ */
+unsigned int pcibios_max_latency = 255;
+
+void pcibios_set_master(struct pci_dev *dev)
+{
+	u8 lat;
+
+	pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
+
+	if (lat < 16)
+		lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;
+	else if (lat > pcibios_max_latency)
+		lat = pcibios_max_latency;
+	else
+		return;
+
+	pci_write_config_byte(dev, PCI_LATENCY_TIMER, lat);
+}
+
+int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
+			enum pci_mmap_state mmap_state, int write_combine)
+{
+	unsigned long prot;
+
+	/* Leave vm_pgoff as-is, the PCI space address is the physical
+	 * address on this platform.
+	 */
+	vma->vm_flags |= VM_LOCKED | VM_IO;
+
+	prot = pgprot_val(vma->vm_page_prot);
+	prot &= ~_PAGE_CACHE;
+	vma->vm_page_prot = __pgprot(prot);
+
+	/* Write-combine setting is ignored */
+	if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+			       vma->vm_end - vma->vm_start,
+			       vma->vm_page_prot))
+		return -EAGAIN;
+
+	return 0;
+}