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-rw-r--r--arch/powerpc/kernel/pci-common.c292
1 files changed, 292 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index c61e9324f77..d804c8d0be0 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -53,6 +53,8 @@ static int global_phb_number; /* Global phb counter */
/* ISA Memory physical address */
resource_size_t isa_mem_base;
+/* Default PCI flags is 0 */
+unsigned int ppc_pci_flags;
struct pci_controller *pcibios_alloc_controller(struct device_node *dev)
{
@@ -821,3 +823,293 @@ void __devinit pcibios_fixup_of_probed_bus(struct pci_bus *bus)
{
__pcibios_fixup_bus(bus);
}
+
+static int skip_isa_ioresource_align(struct pci_dev *dev)
+{
+ if ((ppc_pci_flags & PPC_PCI_CAN_SKIP_ISA_ALIGN) &&
+ !(dev->bus->bridge_ctl & PCI_BRIDGE_CTL_ISA))
+ return 1;
+ return 0;
+}
+
+/*
+ * 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)
+{
+ struct pci_dev *dev = data;
+
+ if (res->flags & IORESOURCE_IO) {
+ resource_size_t start = res->start;
+
+ if (skip_isa_ioresource_align(dev))
+ return;
+ if (start & 0x300) {
+ start = (start + 0x3ff) & ~0x3ff;
+ res->start = start;
+ }
+ }
+}
+EXPORT_SYMBOL(pcibios_align_resource);
+
+/*
+ * Reparent resource children of pr that conflict with res
+ * under res, and make res replace those children.
+ */
+static int __init reparent_resources(struct resource *parent,
+ struct resource *res)
+{
+ struct resource *p, **pp;
+ struct resource **firstpp = NULL;
+
+ for (pp = &parent->child; (p = *pp) != NULL; pp = &p->sibling) {
+ if (p->end < res->start)
+ continue;
+ if (res->end < p->start)
+ break;
+ if (p->start < res->start || p->end > res->end)
+ return -1; /* not completely contained */
+ if (firstpp == NULL)
+ firstpp = pp;
+ }
+ if (firstpp == NULL)
+ return -1; /* didn't find any conflicting entries? */
+ res->parent = parent;
+ res->child = *firstpp;
+ res->sibling = *pp;
+ *firstpp = res;
+ *pp = NULL;
+ for (p = res->child; p != NULL; p = p->sibling) {
+ p->parent = res;
+ DBG(KERN_INFO "PCI: reparented %s [%llx..%llx] under %s\n",
+ p->name,
+ (unsigned long long)p->start,
+ (unsigned long long)p->end, res->name);
+ }
+ return 0;
+}
+
+/*
+ * 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;
+ int i;
+ struct resource *res, *pr;
+
+ /* Depth-First Search on bus tree */
+ list_for_each_entry(bus, bus_list, node) {
+ for (i = 0; i < PCI_BUS_NUM_RESOURCES; ++i) {
+ if ((res = bus->resource[i]) == NULL || !res->flags
+ || res->start > res->end)
+ continue;
+ if (bus->parent == NULL)
+ pr = (res->flags & IORESOURCE_IO)?
+ &ioport_resource : &iomem_resource;
+ else {
+ /* Don't bother with non-root busses when
+ * re-assigning all resources. We clear the
+ * resource flags as if they were colliding
+ * and as such ensure proper re-allocation
+ * later.
+ */
+ if (ppc_pci_flags & PPC_PCI_REASSIGN_ALL_RSRC)
+ goto clear_resource;
+ pr = pci_find_parent_resource(bus->self, res);
+ if (pr == res) {
+ /* this happens when the generic PCI
+ * code (wrongly) decides that this
+ * bridge is transparent -- paulus
+ */
+ continue;
+ }
+ }
+
+ DBG("PCI: %s (bus %d) bridge rsrc %d: %016llx-%016llx "
+ "[0x%x], parent %p (%s)\n",
+ bus->self ? pci_name(bus->self) : "PHB",
+ bus->number, i,
+ (unsigned long long)res->start,
+ (unsigned long long)res->end,
+ (unsigned int)res->flags,
+ pr, (pr && pr->name) ? pr->name : "nil");
+
+ if (pr && !(pr->flags & IORESOURCE_UNSET)) {
+ if (request_resource(pr, res) == 0)
+ continue;
+ /*
+ * Must be a conflict with an existing entry.
+ * Move that entry (or entries) under the
+ * bridge resource and try again.
+ */
+ if (reparent_resources(pr, res) == 0)
+ continue;
+ }
+ printk(KERN_WARNING
+ "PCI: Cannot allocate resource region "
+ "%d of PCI bridge %d, will remap\n",
+ i, bus->number);
+clear_resource:
+ res->flags = 0;
+ }
+ pcibios_allocate_bus_resources(&bus->children);
+ }
+}
+
+static inline void __devinit alloc_resource(struct pci_dev *dev, int idx)
+{
+ struct resource *pr, *r = &dev->resource[idx];
+
+ DBG("PCI: Allocating %s: Resource %d: %016llx..%016llx [%x]\n",
+ pci_name(dev), idx,
+ (unsigned long long)r->start,
+ (unsigned long long)r->end,
+ (unsigned int)r->flags);
+
+ pr = pci_find_parent_resource(dev, r);
+ if (!pr || (pr->flags & IORESOURCE_UNSET) ||
+ request_resource(pr, r) < 0) {
+ printk(KERN_WARNING "PCI: Cannot allocate resource region %d"
+ " of device %s, will remap\n", idx, pci_name(dev));
+ if (pr)
+ DBG("PCI: parent is %p: %016llx-%016llx [%x]\n", pr,
+ (unsigned long long)pr->start,
+ (unsigned long long)pr->end,
+ (unsigned int)pr->flags);
+ /* We'll assign a new address later */
+ r->flags |= IORESOURCE_UNSET;
+ r->end -= r->start;
+ r->start = 0;
+ }
+}
+
+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->flags || (r->flags & IORESOURCE_UNSET))
+ continue; /* Not assigned at all */
+ if (r->flags & IORESOURCE_IO)
+ disabled = !(command & PCI_COMMAND_IO);
+ else
+ disabled = !(command & PCI_COMMAND_MEMORY);
+ if (pass == disabled)
+ alloc_resource(dev, idx);
+ }
+ if (pass)
+ continue;
+ 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);
+ }
+ }
+}
+
+void __init pcibios_resource_survey(void)
+{
+ /* Allocate and assign resources. If we re-assign everything, then
+ * we skip the allocate phase
+ */
+ pcibios_allocate_bus_resources(&pci_root_buses);
+
+ if (!(ppc_pci_flags & PPC_PCI_REASSIGN_ALL_RSRC)) {
+ pcibios_allocate_resources(0);
+ pcibios_allocate_resources(1);
+ }
+
+ if (!(ppc_pci_flags & PPC_PCI_PROBE_ONLY)) {
+ DBG("PCI: Assigning unassigned resouces...\n");
+ pci_assign_unassigned_resources();
+ }
+
+ /* Call machine dependent fixup */
+ if (ppc_md.pcibios_fixup)
+ ppc_md.pcibios_fixup();
+}
+
+#ifdef CONFIG_HOTPLUG
+/* This is used by the pSeries hotplug driver to allocate resource
+ * of newly plugged busses. We can try to consolidate with the
+ * rest of the code later, for now, keep it as-is
+ */
+void __devinit pcibios_claim_one_bus(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+ struct pci_bus *child_bus;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ int i;
+
+ for (i = 0; i < PCI_NUM_RESOURCES; i++) {
+ struct resource *r = &dev->resource[i];
+
+ if (r->parent || !r->start || !r->flags)
+ continue;
+ pci_claim_resource(dev, i);
+ }
+ }
+
+ list_for_each_entry(child_bus, &bus->children, node)
+ pcibios_claim_one_bus(child_bus);
+}
+EXPORT_SYMBOL_GPL(pcibios_claim_one_bus);
+#endif /* CONFIG_HOTPLUG */
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