summaryrefslogtreecommitdiffstats
path: root/drivers/pci/setup-bus.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/pci/setup-bus.c')
-rw-r--r--drivers/pci/setup-bus.c552
1 files changed, 552 insertions, 0 deletions
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
new file mode 100644
index 000000000000..1ba84be0b4c0
--- /dev/null
+++ b/drivers/pci/setup-bus.c
@@ -0,0 +1,552 @@
+/*
+ * drivers/pci/setup-bus.c
+ *
+ * Extruded from code written by
+ * Dave Rusling (david.rusling@reo.mts.dec.com)
+ * David Mosberger (davidm@cs.arizona.edu)
+ * David Miller (davem@redhat.com)
+ *
+ * Support routines for initializing a PCI subsystem.
+ */
+
+/*
+ * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
+ * PCI-PCI bridges cleanup, sorted resource allocation.
+ * Feb 2002, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
+ * Converted to allocation in 3 passes, which gives
+ * tighter packing. Prefetchable range support.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/errno.h>
+#include <linux/ioport.h>
+#include <linux/cache.h>
+#include <linux/slab.h>
+
+
+#define DEBUG_CONFIG 1
+#if DEBUG_CONFIG
+#define DBG(x...) printk(x)
+#else
+#define DBG(x...)
+#endif
+
+#define ROUND_UP(x, a) (((x) + (a) - 1) & ~((a) - 1))
+
+/*
+ * FIXME: IO should be max 256 bytes. However, since we may
+ * have a P2P bridge below a cardbus bridge, we need 4K.
+ */
+#define CARDBUS_IO_SIZE (4096)
+#define CARDBUS_MEM_SIZE (32*1024*1024)
+
+static void __devinit
+pbus_assign_resources_sorted(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+ struct resource *res;
+ struct resource_list head, *list, *tmp;
+ int idx;
+
+ bus->bridge_ctl &= ~PCI_BRIDGE_CTL_VGA;
+
+ head.next = NULL;
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ u16 class = dev->class >> 8;
+
+ /* Don't touch classless devices and host bridges. */
+ if (class == PCI_CLASS_NOT_DEFINED ||
+ class == PCI_CLASS_BRIDGE_HOST)
+ continue;
+
+ if (class == PCI_CLASS_DISPLAY_VGA ||
+ class == PCI_CLASS_NOT_DEFINED_VGA)
+ bus->bridge_ctl |= PCI_BRIDGE_CTL_VGA;
+
+ pdev_sort_resources(dev, &head);
+ }
+
+ for (list = head.next; list;) {
+ res = list->res;
+ idx = res - &list->dev->resource[0];
+ pci_assign_resource(list->dev, idx);
+ tmp = list;
+ list = list->next;
+ kfree(tmp);
+ }
+}
+
+static void __devinit
+pci_setup_cardbus(struct pci_bus *bus)
+{
+ struct pci_dev *bridge = bus->self;
+ struct pci_bus_region region;
+
+ printk("PCI: Bus %d, cardbus bridge: %s\n",
+ bus->number, pci_name(bridge));
+
+ pcibios_resource_to_bus(bridge, &region, bus->resource[0]);
+ if (bus->resource[0]->flags & IORESOURCE_IO) {
+ /*
+ * The IO resource is allocated a range twice as large as it
+ * would normally need. This allows us to set both IO regs.
+ */
+ printk(" IO window: %08lx-%08lx\n",
+ region.start, region.end);
+ pci_write_config_dword(bridge, PCI_CB_IO_BASE_0,
+ region.start);
+ pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0,
+ region.end);
+ }
+
+ pcibios_resource_to_bus(bridge, &region, bus->resource[1]);
+ if (bus->resource[1]->flags & IORESOURCE_IO) {
+ printk(" IO window: %08lx-%08lx\n",
+ region.start, region.end);
+ pci_write_config_dword(bridge, PCI_CB_IO_BASE_1,
+ region.start);
+ pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1,
+ region.end);
+ }
+
+ pcibios_resource_to_bus(bridge, &region, bus->resource[2]);
+ if (bus->resource[2]->flags & IORESOURCE_MEM) {
+ printk(" PREFETCH window: %08lx-%08lx\n",
+ region.start, region.end);
+ pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0,
+ region.start);
+ pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0,
+ region.end);
+ }
+
+ pcibios_resource_to_bus(bridge, &region, bus->resource[3]);
+ if (bus->resource[3]->flags & IORESOURCE_MEM) {
+ printk(" MEM window: %08lx-%08lx\n",
+ region.start, region.end);
+ pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_1,
+ region.start);
+ pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_1,
+ region.end);
+ }
+}
+
+/* Initialize bridges with base/limit values we have collected.
+ PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
+ requires that if there is no I/O ports or memory behind the
+ bridge, corresponding range must be turned off by writing base
+ value greater than limit to the bridge's base/limit registers.
+
+ Note: care must be taken when updating I/O base/limit registers
+ of bridges which support 32-bit I/O. This update requires two
+ config space writes, so it's quite possible that an I/O window of
+ the bridge will have some undesirable address (e.g. 0) after the
+ first write. Ditto 64-bit prefetchable MMIO. */
+static void __devinit
+pci_setup_bridge(struct pci_bus *bus)
+{
+ struct pci_dev *bridge = bus->self;
+ struct pci_bus_region region;
+ u32 l, io_upper16;
+
+ DBG(KERN_INFO "PCI: Bridge: %s\n", pci_name(bridge));
+
+ /* Set up the top and bottom of the PCI I/O segment for this bus. */
+ pcibios_resource_to_bus(bridge, &region, bus->resource[0]);
+ if (bus->resource[0]->flags & IORESOURCE_IO) {
+ pci_read_config_dword(bridge, PCI_IO_BASE, &l);
+ l &= 0xffff0000;
+ l |= (region.start >> 8) & 0x00f0;
+ l |= region.end & 0xf000;
+ /* Set up upper 16 bits of I/O base/limit. */
+ io_upper16 = (region.end & 0xffff0000) | (region.start >> 16);
+ DBG(KERN_INFO " IO window: %04lx-%04lx\n",
+ region.start, region.end);
+ }
+ else {
+ /* Clear upper 16 bits of I/O base/limit. */
+ io_upper16 = 0;
+ l = 0x00f0;
+ DBG(KERN_INFO " IO window: disabled.\n");
+ }
+ /* Temporarily disable the I/O range before updating PCI_IO_BASE. */
+ pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, 0x0000ffff);
+ /* Update lower 16 bits of I/O base/limit. */
+ pci_write_config_dword(bridge, PCI_IO_BASE, l);
+ /* Update upper 16 bits of I/O base/limit. */
+ pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, io_upper16);
+
+ /* Set up the top and bottom of the PCI Memory segment
+ for this bus. */
+ pcibios_resource_to_bus(bridge, &region, bus->resource[1]);
+ if (bus->resource[1]->flags & IORESOURCE_MEM) {
+ l = (region.start >> 16) & 0xfff0;
+ l |= region.end & 0xfff00000;
+ DBG(KERN_INFO " MEM window: %08lx-%08lx\n",
+ region.start, region.end);
+ }
+ else {
+ l = 0x0000fff0;
+ DBG(KERN_INFO " MEM window: disabled.\n");
+ }
+ pci_write_config_dword(bridge, PCI_MEMORY_BASE, l);
+
+ /* Clear out the upper 32 bits of PREF limit.
+ If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily
+ disables PREF range, which is ok. */
+ pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0);
+
+ /* Set up PREF base/limit. */
+ pcibios_resource_to_bus(bridge, &region, bus->resource[2]);
+ if (bus->resource[2]->flags & IORESOURCE_PREFETCH) {
+ l = (region.start >> 16) & 0xfff0;
+ l |= region.end & 0xfff00000;
+ DBG(KERN_INFO " PREFETCH window: %08lx-%08lx\n",
+ region.start, region.end);
+ }
+ else {
+ l = 0x0000fff0;
+ DBG(KERN_INFO " PREFETCH window: disabled.\n");
+ }
+ pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);
+
+ /* Clear out the upper 32 bits of PREF base. */
+ pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, 0);
+
+ pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl);
+}
+
+/* Check whether the bridge supports optional I/O and
+ prefetchable memory ranges. If not, the respective
+ base/limit registers must be read-only and read as 0. */
+static void __devinit
+pci_bridge_check_ranges(struct pci_bus *bus)
+{
+ u16 io;
+ u32 pmem;
+ struct pci_dev *bridge = bus->self;
+ struct resource *b_res;
+
+ b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
+ b_res[1].flags |= IORESOURCE_MEM;
+
+ pci_read_config_word(bridge, PCI_IO_BASE, &io);
+ if (!io) {
+ pci_write_config_word(bridge, PCI_IO_BASE, 0xf0f0);
+ pci_read_config_word(bridge, PCI_IO_BASE, &io);
+ pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
+ }
+ if (io)
+ b_res[0].flags |= IORESOURCE_IO;
+ /* DECchip 21050 pass 2 errata: the bridge may miss an address
+ disconnect boundary by one PCI data phase.
+ Workaround: do not use prefetching on this device. */
+ if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
+ return;
+ pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
+ if (!pmem) {
+ pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
+ 0xfff0fff0);
+ pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
+ pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
+ }
+ if (pmem)
+ b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
+}
+
+/* Helper function for sizing routines: find first available
+ bus resource of a given type. Note: we intentionally skip
+ the bus resources which have already been assigned (that is,
+ have non-NULL parent resource). */
+static struct resource * __devinit
+find_free_bus_resource(struct pci_bus *bus, unsigned long type)
+{
+ int i;
+ struct resource *r;
+ unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
+ IORESOURCE_PREFETCH;
+
+ for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
+ r = bus->resource[i];
+ if (r && (r->flags & type_mask) == type && !r->parent)
+ return r;
+ }
+ return NULL;
+}
+
+/* Sizing the IO windows of the PCI-PCI bridge is trivial,
+ since these windows have 4K granularity and the IO ranges
+ of non-bridge PCI devices are limited to 256 bytes.
+ We must be careful with the ISA aliasing though. */
+static void __devinit
+pbus_size_io(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+ struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
+ unsigned long size = 0, size1 = 0;
+
+ if (!b_res)
+ return;
+
+ 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];
+ unsigned long r_size;
+
+ if (r->parent || !(r->flags & IORESOURCE_IO))
+ continue;
+ r_size = r->end - r->start + 1;
+
+ if (r_size < 0x400)
+ /* Might be re-aligned for ISA */
+ size += r_size;
+ else
+ size1 += r_size;
+ }
+ }
+/* To be fixed in 2.5: we should have sort of HAVE_ISA
+ flag in the struct pci_bus. */
+#if defined(CONFIG_ISA) || defined(CONFIG_EISA)
+ size = (size & 0xff) + ((size & ~0xffUL) << 2);
+#endif
+ size = ROUND_UP(size + size1, 4096);
+ if (!size) {
+ b_res->flags = 0;
+ return;
+ }
+ /* Alignment of the IO window is always 4K */
+ b_res->start = 4096;
+ b_res->end = b_res->start + size - 1;
+}
+
+/* Calculate the size of the bus and minimal alignment which
+ guarantees that all child resources fit in this size. */
+static int __devinit
+pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type)
+{
+ struct pci_dev *dev;
+ unsigned long min_align, align, size;
+ unsigned long aligns[12]; /* Alignments from 1Mb to 2Gb */
+ int order, max_order;
+ struct resource *b_res = find_free_bus_resource(bus, type);
+
+ if (!b_res)
+ return 0;
+
+ memset(aligns, 0, sizeof(aligns));
+ max_order = 0;
+ size = 0;
+
+ 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];
+ unsigned long r_size;
+
+ if (r->parent || (r->flags & mask) != type)
+ continue;
+ r_size = r->end - r->start + 1;
+ /* For bridges size != alignment */
+ align = (i < PCI_BRIDGE_RESOURCES) ? r_size : r->start;
+ order = __ffs(align) - 20;
+ if (order > 11) {
+ printk(KERN_WARNING "PCI: region %s/%d "
+ "too large: %lx-%lx\n",
+ pci_name(dev), i, r->start, r->end);
+ r->flags = 0;
+ continue;
+ }
+ size += r_size;
+ if (order < 0)
+ order = 0;
+ /* Exclude ranges with size > align from
+ calculation of the alignment. */
+ if (r_size == align)
+ aligns[order] += align;
+ if (order > max_order)
+ max_order = order;
+ }
+ }
+
+ align = 0;
+ min_align = 0;
+ for (order = 0; order <= max_order; order++) {
+ unsigned long align1 = 1UL << (order + 20);
+
+ if (!align)
+ min_align = align1;
+ else if (ROUND_UP(align + min_align, min_align) < align1)
+ min_align = align1 >> 1;
+ align += aligns[order];
+ }
+ size = ROUND_UP(size, min_align);
+ if (!size) {
+ b_res->flags = 0;
+ return 1;
+ }
+ b_res->start = min_align;
+ b_res->end = size + min_align - 1;
+ return 1;
+}
+
+static void __devinit
+pci_bus_size_cardbus(struct pci_bus *bus)
+{
+ struct pci_dev *bridge = bus->self;
+ struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
+ u16 ctrl;
+
+ /*
+ * Reserve some resources for CardBus. We reserve
+ * a fixed amount of bus space for CardBus bridges.
+ */
+ b_res[0].start = CARDBUS_IO_SIZE;
+ b_res[0].end = b_res[0].start + CARDBUS_IO_SIZE - 1;
+ b_res[0].flags |= IORESOURCE_IO;
+
+ b_res[1].start = CARDBUS_IO_SIZE;
+ b_res[1].end = b_res[1].start + CARDBUS_IO_SIZE - 1;
+ b_res[1].flags |= IORESOURCE_IO;
+
+ /*
+ * Check whether prefetchable memory is supported
+ * by this bridge.
+ */
+ pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
+ if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) {
+ ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0;
+ pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
+ pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
+ }
+
+ /*
+ * If we have prefetchable memory support, allocate
+ * two regions. Otherwise, allocate one region of
+ * twice the size.
+ */
+ if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
+ b_res[2].start = CARDBUS_MEM_SIZE;
+ b_res[2].end = b_res[2].start + CARDBUS_MEM_SIZE - 1;
+ b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
+
+ b_res[3].start = CARDBUS_MEM_SIZE;
+ b_res[3].end = b_res[3].start + CARDBUS_MEM_SIZE - 1;
+ b_res[3].flags |= IORESOURCE_MEM;
+ } else {
+ b_res[3].start = CARDBUS_MEM_SIZE * 2;
+ b_res[3].end = b_res[3].start + CARDBUS_MEM_SIZE * 2 - 1;
+ b_res[3].flags |= IORESOURCE_MEM;
+ }
+}
+
+void __devinit
+pci_bus_size_bridges(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+ unsigned long mask, prefmask;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ struct pci_bus *b = dev->subordinate;
+ if (!b)
+ continue;
+
+ switch (dev->class >> 8) {
+ case PCI_CLASS_BRIDGE_CARDBUS:
+ pci_bus_size_cardbus(b);
+ break;
+
+ case PCI_CLASS_BRIDGE_PCI:
+ default:
+ pci_bus_size_bridges(b);
+ break;
+ }
+ }
+
+ /* The root bus? */
+ if (!bus->self)
+ return;
+
+ switch (bus->self->class >> 8) {
+ case PCI_CLASS_BRIDGE_CARDBUS:
+ /* don't size cardbuses yet. */
+ break;
+
+ case PCI_CLASS_BRIDGE_PCI:
+ pci_bridge_check_ranges(bus);
+ default:
+ pbus_size_io(bus);
+ /* If the bridge supports prefetchable range, size it
+ separately. If it doesn't, or its prefetchable window
+ has already been allocated by arch code, try
+ non-prefetchable range for both types of PCI memory
+ resources. */
+ mask = IORESOURCE_MEM;
+ prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
+ if (pbus_size_mem(bus, prefmask, prefmask))
+ mask = prefmask; /* Success, size non-prefetch only. */
+ pbus_size_mem(bus, mask, IORESOURCE_MEM);
+ break;
+ }
+}
+EXPORT_SYMBOL(pci_bus_size_bridges);
+
+void __devinit
+pci_bus_assign_resources(struct pci_bus *bus)
+{
+ struct pci_bus *b;
+ struct pci_dev *dev;
+
+ pbus_assign_resources_sorted(bus);
+
+ if (bus->bridge_ctl & PCI_BRIDGE_CTL_VGA) {
+ /* Propagate presence of the VGA to upstream bridges */
+ for (b = bus; b->parent; b = b->parent) {
+ b->bridge_ctl |= PCI_BRIDGE_CTL_VGA;
+ }
+ }
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ b = dev->subordinate;
+ if (!b)
+ continue;
+
+ pci_bus_assign_resources(b);
+
+ switch (dev->class >> 8) {
+ case PCI_CLASS_BRIDGE_PCI:
+ pci_setup_bridge(b);
+ break;
+
+ case PCI_CLASS_BRIDGE_CARDBUS:
+ pci_setup_cardbus(b);
+ break;
+
+ default:
+ printk(KERN_INFO "PCI: not setting up bridge %s "
+ "for bus %d\n", pci_name(dev), b->number);
+ break;
+ }
+ }
+}
+EXPORT_SYMBOL(pci_bus_assign_resources);
+
+void __init
+pci_assign_unassigned_resources(void)
+{
+ struct pci_bus *bus;
+
+ /* Depth first, calculate sizes and alignments of all
+ subordinate buses. */
+ list_for_each_entry(bus, &pci_root_buses, node) {
+ pci_bus_size_bridges(bus);
+ }
+ /* Depth last, allocate resources and update the hardware. */
+ list_for_each_entry(bus, &pci_root_buses, node) {
+ pci_bus_assign_resources(bus);
+ pci_enable_bridges(bus);
+ }
+}
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-11-06 17:56:46 +0100