/* * This file is part of the coreboot project. * * It was originally based on the Linux kernel (arch/i386/kernel/pci-pc.c). * * Modifications are: * Copyright (C) 2003 Eric Biederman * Copyright (C) 2003-2004 Linux Networx * (Written by Eric Biederman for Linux Networx) * Copyright (C) 2003 Ronald G. Minnich * Copyright (C) 2004-2005 Li-Ta Lo * Copyright (C) 2005-2006 Tyan * (Written by Yinghai Lu for Tyan) * Copyright (C) 2005-2006 Stefan Reinauer * Copyright (C) 2009 Myles Watson */ /* * (c) 1999--2000 Martin Mares */ /* * Lots of mods by Ron Minnich , with * the final architecture guidance from Tom Merritt . * * In particular, we changed from the one-pass original version to * Tom's recommended multiple-pass version. I wasn't sure about doing * it with multiple passes, until I actually started doing it and saw * the wisdom of Tom's recommendations... * * Lots of cleanups by Eric Biederman to handle bridges, and to * handle resource allocation for non-PCI devices. */ #include #include #include #include #include #include #include #include #include #if CONFIG_ARCH_X86 #include #endif /** Linked list of ALL devices */ struct device *all_devices = &dev_root; /** Pointer to the last device */ extern struct device *last_dev; /** Linked list of free resources */ struct resource *free_resources = NULL; /** * Initialize all chips of statically known devices. * * Will be called before bus enumeration to initialize chips stated in the * device tree. */ void dev_initialize_chips(void) { struct device *dev; for (dev = all_devices; dev; dev = dev->next) { /* Initialize chip if we haven't yet. */ if (dev->chip_ops && dev->chip_ops->init && !dev->chip_ops->initialized) { dev->chip_ops->init(dev->chip_info); dev->chip_ops->initialized = 1; } } } DECLARE_SPIN_LOCK(dev_lock) #if CONFIG_GFXUMA /* IGD UMA memory */ uint64_t uma_memory_base = 0; uint64_t uma_memory_size = 0; #endif /** * Allocate a new device structure. * * Allocte a new device structure and attach it to the device tree as a * child of the parent bus. * * @param parent Parent bus the newly created device should be attached to. * @param path Path to the device to be created. * @return Pointer to the newly created device structure. * * @see device_path */ static device_t __alloc_dev(struct bus *parent, struct device_path *path) { device_t dev, child; /* Find the last child of our parent. */ for (child = parent->children; child && child->sibling; /* */ ) child = child->sibling; dev = malloc(sizeof(*dev)); if (dev == 0) die("alloc_dev(): out of memory.\n"); memset(dev, 0, sizeof(*dev)); memcpy(&dev->path, path, sizeof(*path)); /* By default devices are enabled. */ dev->enabled = 1; /* Add the new device to the list of children of the bus. */ dev->bus = parent; if (child) child->sibling = dev; else parent->children = dev; /* Append a new device to the global device list. * The list is used to find devices once everything is set up. */ last_dev->next = dev; last_dev = dev; return dev; } device_t alloc_dev(struct bus *parent, struct device_path *path) { device_t dev; spin_lock(&dev_lock); dev = __alloc_dev(parent, path); spin_unlock(&dev_lock); return dev; } /** * See if a device structure already exists and if not allocate it. * * @param parent The bus to find the device on. * @param path The relative path from the bus to the appropriate device. * @return Pointer to a device structure for the device on bus at path. */ device_t alloc_find_dev(struct bus *parent, struct device_path *path) { device_t child; spin_lock(&dev_lock); child = find_dev_path(parent, path); if (!child) child = __alloc_dev(parent, path); spin_unlock(&dev_lock); return child; } /** * Round a number up to an alignment. * * @param val The starting value. * @param roundup Alignment as a power of two. * @return Rounded up number. */ static resource_t round(resource_t val, unsigned long pow) { resource_t mask; mask = (1ULL << pow) - 1ULL; val += mask; val &= ~mask; return val; } /** * Read the resources on all devices of a given bus. * * @param bus Bus to read the resources on. */ static void read_resources(struct bus *bus) { struct device *curdev; printk(BIOS_SPEW, "%s %s bus %x link: %d\n", dev_path(bus->dev), __func__, bus->secondary, bus->link_num); /* Walk through all devices and find which resources they need. */ for (curdev = bus->children; curdev; curdev = curdev->sibling) { struct bus *link; if (!curdev->enabled) continue; if (!curdev->ops || !curdev->ops->read_resources) { printk(BIOS_ERR, "%s missing read_resources\n", dev_path(curdev)); continue; } curdev->ops->read_resources(curdev); /* Read in the resources behind the current device's links. */ for (link = curdev->link_list; link; link = link->next) read_resources(link); } printk(BIOS_SPEW, "%s read_resources bus %d link: %d done\n", dev_path(bus->dev), bus->secondary, bus->link_num); } struct pick_largest_state { struct resource *last; struct device *result_dev; struct resource *result; int seen_last; }; static void pick_largest_resource(void *gp, struct device *dev, struct resource *resource) { struct pick_largest_state *state = gp; struct resource *last; last = state->last; /* Be certain to pick the successor to last. */ if (resource == last) { state->seen_last = 1; return; } if (resource->flags & IORESOURCE_FIXED) return; /* Skip it. */ if (last && ((last->align < resource->align) || ((last->align == resource->align) && (last->size < resource->size)) || ((last->align == resource->align) && (last->size == resource->size) && (!state->seen_last)))) { return; } if (!state->result || (state->result->align < resource->align) || ((state->result->align == resource->align) && (state->result->size < resource->size))) { state->result_dev = dev; state->result = resource; } } static struct device *largest_resource(struct bus *bus, struct resource **result_res, unsigned long type_mask, unsigned long type) { struct pick_largest_state state; state.last = *result_res; state.result_dev = NULL; state.result = NULL; state.seen_last = 0; search_bus_resources(bus, type_mask, type, pick_largest_resource, &state); *result_res = state.result; return state.result_dev; } /** * This function is the guts of the resource allocator. * * The problem. * - Allocate resource locations for every device. * - Don't overlap, and follow the rules of bridges. * - Don't overlap with resources in fixed locations. * - Be efficient so we don't have ugly strategies. * * The strategy. * - Devices that have fixed addresses are the minority so don't * worry about them too much. Instead only use part of the address * space for devices with programmable addresses. This easily handles * everything except bridges. * * - PCI devices are required to have their sizes and their alignments * equal. In this case an optimal solution to the packing problem * exists. Allocate all devices from highest alignment to least * alignment or vice versa. Use this. * * - So we can handle more than PCI run two allocation passes on bridges. The * first to see how large the resources are behind the bridge, and what * their alignment requirements are. The second to assign a safe address to * the devices behind the bridge. This allows us to treat a bridge as just * a device with a couple of resources, and not need to special case it in * the allocator. Also this allows handling of other types of bridges. * * @param bus The bus we are traversing. * @param bridge The bridge resource which must contain the bus' resources. * @param type_mask This value gets ANDed with the resource type. * @param type This value must match the result of the AND. * @return TODO */ static void compute_resources(struct bus *bus, struct resource *bridge, unsigned long type_mask, unsigned long type) { struct device *dev; struct resource *resource; resource_t base; base = round(bridge->base, bridge->align); printk(BIOS_SPEW, "%s %s_%s: base: %llx size: %llx align: %d gran: %d" " limit: %llx\n", dev_path(bus->dev), __func__, (type & IORESOURCE_IO) ? "io" : (type & IORESOURCE_PREFETCH) ? "prefmem" : "mem", base, bridge->size, bridge->align, bridge->gran, bridge->limit); /* For each child which is a bridge, compute the resource needs. */ for (dev = bus->children; dev; dev = dev->sibling) { struct resource *child_bridge; if (!dev->link_list) continue; /* Find the resources with matching type flags. */ for (child_bridge = dev->resource_list; child_bridge; child_bridge = child_bridge->next) { struct bus* link; if (!(child_bridge->flags & IORESOURCE_BRIDGE) || (child_bridge->flags & type_mask) != type) continue; /* * Split prefetchable memory if combined. Many domains * use the same address space for prefetchable memory * and non-prefetchable memory. Bridges below them need * it separated. Add the PREFETCH flag to the type_mask * and type. */ link = dev->link_list; while (link && link->link_num != IOINDEX_LINK(child_bridge->index)) link = link->next; if (link == NULL) { printk(BIOS_ERR, "link %ld not found on %s\n", IOINDEX_LINK(child_bridge->index), dev_path(dev)); } compute_resources(link, child_bridge, type_mask | IORESOURCE_PREFETCH, type | (child_bridge->flags & IORESOURCE_PREFETCH)); } } /* Remember we haven't found anything yet. */ resource = NULL; /* * Walk through all the resources on the current bus and compute the * amount of address space taken by them. Take granularity and * alignment into account. */ while ((dev = largest_resource(bus, &resource, type_mask, type))) { /* Size 0 resources can be skipped. */ if (!resource->size) continue; /* Propagate the resource alignment to the bridge resource. */ if (resource->align > bridge->align) bridge->align = resource->align; /* Propagate the resource limit to the bridge register. */ if (bridge->limit > resource->limit) bridge->limit = resource->limit; /* Warn if it looks like APICs aren't declared. */ if ((resource->limit == 0xffffffff) && (resource->flags & IORESOURCE_ASSIGNED)) { printk(BIOS_ERR, "Resource limit looks wrong! (no APIC?)\n"); printk(BIOS_ERR, "%s %02lx limit %08llx\n", dev_path(dev), resource->index, resource->limit); } if (resource->flags & IORESOURCE_IO) { /* * Don't allow potential aliases over the legacy PCI * expansion card addresses. The legacy PCI decodes * only 10 bits, uses 0x100 - 0x3ff. Therefore, only * 0x00 - 0xff can be used out of each 0x400 block of * I/O space. */ if ((base & 0x300) != 0) { base = (base & ~0x3ff) + 0x400; } /* * Don't allow allocations in the VGA I/O range. * PCI has special cases for that. */ else if ((base >= 0x3b0) && (base <= 0x3df)) { base = 0x3e0; } } /* Base must be aligned. */ base = round(base, resource->align); resource->base = base; base += resource->size; printk(BIOS_SPEW, "%s %02lx * [0x%llx - 0x%llx] %s\n", dev_path(dev), resource->index, resource->base, resource->base + resource->size - 1, (resource->flags & IORESOURCE_IO) ? "io" : (resource->flags & IORESOURCE_PREFETCH) ? "prefmem" : "mem"); } /* * A PCI bridge resource does not need to be a power of two size, but * it does have a minimum granularity. Round the size up to that * minimum granularity so we know not to place something else at an * address postitively decoded by the bridge. */ bridge->size = round(base, bridge->gran) - round(bridge->base, bridge->align); printk(BIOS_SPEW, "%s %s_%s: base: %llx size: %llx align: %d gran: %d" " limit: %llx done\n", dev_path(bus->dev), __func__, (bridge->flags & IORESOURCE_IO) ? "io" : (bridge->flags & IORESOURCE_PREFETCH) ? "prefmem" : "mem", base, bridge->size, bridge->align, bridge->gran, bridge->limit); } /** * This function is the second part of the resource allocator. * * See the compute_resources function for a more detailed explanation. * * This function assigns the resources a value. * * @param bus The bus we are traversing. * @param bridge The bridge resource which must contain the bus' resources. * @param type_mask This value gets ANDed with the resource type. * @param type This value must match the result of the AND. * * @see compute_resources */ static void allocate_resources(struct bus *bus, struct resource *bridge, unsigned long type_mask, unsigned long type) { struct device *dev; struct resource *resource; resource_t base; base = bridge->base; printk(BIOS_SPEW, "%s %s_%s: base:%llx size:%llx align:%d gran:%d " "limit:%llx\n", dev_path(bus->dev), __func__, (type & IORESOURCE_IO) ? "io" : (type & IORESOURCE_PREFETCH) ? "prefmem" : "mem", base, bridge->size, bridge->align, bridge->gran, bridge->limit); /* Remember we haven't found anything yet. */ resource = NULL; /* * Walk through all the resources on the current bus and allocate them * address space. */ while ((dev = largest_resource(bus, &resource, type_mask, type))) { /* Propagate the bridge limit to the resource register. */ if (resource->limit > bridge->limit) resource->limit = bridge->limit; /* Size 0 resources can be skipped. */ if (!resource->size) { /* Set the base to limit so it doesn't confuse tolm. */ resource->base = resource->limit; resource->flags |= IORESOURCE_ASSIGNED; continue; } if (resource->flags & IORESOURCE_IO) { /* * Don't allow potential aliases over the legacy PCI * expansion card addresses. The legacy PCI decodes * only 10 bits, uses 0x100 - 0x3ff. Therefore, only * 0x00 - 0xff can be used out of each 0x400 block of * I/O space. */ if ((base & 0x300) != 0) { base = (base & ~0x3ff) + 0x400; } /* * Don't allow allocations in the VGA I/O range. * PCI has special cases for that. */ else if ((base >= 0x3b0) && (base <= 0x3df)) { base = 0x3e0; } } if ((round(base, resource->align) + resource->size - 1) <= resource->limit) { /* Base must be aligned. */ base = round(base, resource->align); resource->base = base; resource->flags |= IORESOURCE_ASSIGNED; resource->flags &= ~IORESOURCE_STORED; base += resource->size; } else { printk(BIOS_ERR, "!! Resource didn't fit !!\n"); printk(BIOS_ERR, " aligned base %llx size %llx " "limit %llx\n", round(base, resource->align), resource->size, resource->limit); printk(BIOS_ERR, " %llx needs to be <= %llx " "(limit)\n", (round(base, resource->align) + resource->size) - 1, resource->limit); printk(BIOS_ERR, " %s%s %02lx * [0x%llx - 0x%llx]" " %s\n", (resource->flags & IORESOURCE_ASSIGNED) ? "Assigned: " : "", dev_path(dev), resource->index, resource->base, resource->base + resource->size - 1, (resource->flags & IORESOURCE_IO) ? "io" : (resource->flags & IORESOURCE_PREFETCH) ? "prefmem" : "mem"); } printk(BIOS_SPEW, "%s%s %02lx * [0x%llx - 0x%llx] %s\n", (resource->flags & IORESOURCE_ASSIGNED) ? "Assigned: " : "", dev_path(dev), resource->index, resource->base, resource->size ? resource->base + resource->size - 1 : resource->base, (resource->flags & IORESOURCE_IO) ? "io" : (resource->flags & IORESOURCE_PREFETCH) ? "prefmem" : "mem"); } /* * A PCI bridge resource does not need to be a power of two size, but * it does have a minimum granularity. Round the size up to that * minimum granularity so we know not to place something else at an * address positively decoded by the bridge. */ bridge->flags |= IORESOURCE_ASSIGNED; printk(BIOS_SPEW, "%s %s_%s: next_base: %llx size: %llx align: %d " "gran: %d done\n", dev_path(bus->dev), __func__, (type & IORESOURCE_IO) ? "io" : (type & IORESOURCE_PREFETCH) ? "prefmem" : "mem", base, bridge->size, bridge->align, bridge->gran); /* For each child which is a bridge, allocate_resources. */ for (dev = bus->children; dev; dev = dev->sibling) { struct resource *child_bridge; if (!dev->link_list) continue; /* Find the resources with matching type flags. */ for (child_bridge = dev->resource_list; child_bridge; child_bridge = child_bridge->next) { struct bus* link; if (!(child_bridge->flags & IORESOURCE_BRIDGE) || (child_bridge->flags & type_mask) != type) continue; /* * Split prefetchable memory if combined. Many domains * use the same address space for prefetchable memory * and non-prefetchable memory. Bridges below them need * it separated. Add the PREFETCH flag to the type_mask * and type. */ link = dev->link_list; while (link && link->link_num != IOINDEX_LINK(child_bridge->index)) link = link->next; if (link == NULL) printk(BIOS_ERR, "link %ld not found on %s\n", IOINDEX_LINK(child_bridge->index), dev_path(dev)); allocate_resources(link, child_bridge, type_mask | IORESOURCE_PREFETCH, type | (child_bridge->flags & IORESOURCE_PREFETCH)); } } } #if CONFIG_PCI_64BIT_PREF_MEM #define MEM_MASK (IORESOURCE_PREFETCH | IORESOURCE_MEM) #else #define MEM_MASK (IORESOURCE_MEM) #endif #define IO_MASK (IORESOURCE_IO) #define PREF_TYPE (IORESOURCE_PREFETCH | IORESOURCE_MEM) #define MEM_TYPE (IORESOURCE_MEM) #define IO_TYPE (IORESOURCE_IO) struct constraints { struct resource pref, io, mem; }; static void constrain_resources(struct device *dev, struct constraints* limits) { struct device *child; struct resource *res; struct resource *lim; struct bus *link; printk(BIOS_SPEW, "%s: %s\n", __func__, dev_path(dev)); /* Constrain limits based on the fixed resources of this device. */ for (res = dev->resource_list; res; res = res->next) { if (!(res->flags & IORESOURCE_FIXED)) continue; if (!res->size) { /* It makes no sense to have 0-sized, fixed resources.*/ printk(BIOS_ERR, "skipping %s@%lx fixed resource, " "size=0!\n", dev_path(dev), res->index); continue; } /* PREFETCH, MEM, or I/O - skip any others. */ if ((res->flags & MEM_MASK) == PREF_TYPE) lim = &limits->pref; else if ((res->flags & MEM_MASK) == MEM_TYPE) lim = &limits->mem; else if ((res->flags & IO_MASK) == IO_TYPE) lim = &limits->io; else continue; /* * Is it a fixed resource outside the current known region? * If so, we don't have to consider it - it will be handled * correctly and doesn't affect current region's limits. */ if (((res->base + res->size -1) < lim->base) || (res->base > lim->limit)) continue; /* * Choose to be above or below fixed resources. This check is * signed so that "negative" amounts of space are handled * correctly. */ if ((signed long long)(lim->limit - (res->base + res->size -1)) > (signed long long)(res->base - lim->base)) lim->base = res->base + res->size; else lim->limit = res->base -1; } /* Descend into every enabled child and look for fixed resources. */ for (link = dev->link_list; link; link = link->next) { for (child = link->children; child; child = child->sibling) { if (child->enabled) constrain_resources(child, limits); } } } static void avoid_fixed_resources(struct device *dev) { struct constraints limits; struct resource *res; printk(BIOS_SPEW, "%s: %s\n", __func__, dev_path(dev)); /* Initialize constraints to maximum size. */ limits.pref.base = 0; limits.pref.limit = 0xffffffffffffffffULL; limits.io.base = 0; limits.io.limit = 0xffffffffffffffffULL; limits.mem.base = 0; limits.mem.limit = 0xffffffffffffffffULL; /* Constrain the limits to dev's initial resources. */ for (res = dev->resource_list; res; res = res->next) { if ((res->flags & IORESOURCE_FIXED)) continue; printk(BIOS_SPEW, "%s:@%s %02lx limit %08llx\n", __func__, dev_path(dev), res->index, res->limit); if ((res->flags & MEM_MASK) == PREF_TYPE && (res->limit < limits.pref.limit)) limits.pref.limit = res->limit; if ((res->flags & MEM_MASK) == MEM_TYPE && (res->limit < limits.mem.limit)) limits.mem.limit = res->limit; if ((res->flags & IO_MASK) == IO_TYPE && (res->limit < limits.io.limit)) limits.io.limit = res->limit; } /* Look through the tree for fixed resources and update the limits. */ constrain_resources(dev, &limits); /* Update dev's resources with new limits. */ for (res = dev->resource_list; res; res = res->next) { struct resource *lim; if ((res->flags & IORESOURCE_FIXED)) continue; /* PREFETCH, MEM, or I/O - skip any others. */ if ((res->flags & MEM_MASK) == PREF_TYPE) lim = &limits.pref; else if ((res->flags & MEM_MASK) == MEM_TYPE) lim = &limits.mem; else if ((res->flags & IO_MASK) == IO_TYPE) lim = &limits.io; else continue; printk(BIOS_SPEW, "%s2: %s@%02lx limit %08llx\n", __func__, dev_path(dev), res->index, res->limit); printk(BIOS_SPEW, "\tlim->base %08llx lim->limit %08llx\n", lim->base, lim->limit); /* Is the resource outside the limits? */ if (lim->base > res->base) res->base = lim->base; if (res->limit > lim->limit) res->limit = lim->limit; } } device_t vga_pri = 0; static void set_vga_bridge_bits(void) { /* * FIXME: Modify set_vga_bridge() so it is less PCI centric! * This function knows too much about PCI stuff, it should be just * an iterator/visitor. */ /* FIXME: Handle the VGA palette snooping. */ struct device *dev, *vga, *vga_onboard; struct bus *bus; bus = 0; vga = 0; vga_onboard = 0; dev = NULL; while ((dev = dev_find_class(PCI_CLASS_DISPLAY_VGA << 8, dev))) { if (!dev->enabled) continue; printk(BIOS_DEBUG, "found VGA at %s\n", dev_path(dev)); if (dev->on_mainboard) { vga_onboard = dev; } else { vga = dev; } /* It isn't safe to enable all VGA cards. */ dev->command &= ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO); } if (!vga) vga = vga_onboard; if (CONFIG_ONBOARD_VGA_IS_PRIMARY && vga_onboard) vga = vga_onboard; /* If we prefer plugin VGA over chipset VGA, the chipset might want to know. */ if (!CONFIG_ONBOARD_VGA_IS_PRIMARY && (vga != vga_onboard) && vga_onboard && vga_onboard->ops && vga_onboard->ops->disable) { printk(BIOS_DEBUG, "Use plugin graphics over integrated.\n"); vga_onboard->ops->disable(vga_onboard); } if (vga) { /* VGA is first add-on card or the only onboard VGA. */ printk(BIOS_DEBUG, "Setting up VGA for %s\n", dev_path(vga)); /* All legacy VGA cards have MEM & I/O space registers. */ vga->command |= (PCI_COMMAND_MEMORY | PCI_COMMAND_IO); vga_pri = vga; bus = vga->bus; } /* Now walk up the bridges setting the VGA enable. */ while (bus) { printk(BIOS_DEBUG, "Setting PCI_BRIDGE_CTL_VGA for bridge %s\n", dev_path(bus->dev)); bus->bridge_ctrl |= PCI_BRIDGE_CTL_VGA; bus = (bus == bus->dev->bus) ? 0 : bus->dev->bus; } } /** * Assign the computed resources to the devices on the bus. * * Use the device specific set_resources() method to store the computed * resources to hardware. For bridge devices, the set_resources() method * has to recurse into every down stream buses. * * Mutual recursion: * assign_resources() -> device_operation::set_resources() * device_operation::set_resources() -> assign_resources() * * @param bus Pointer to the structure for this bus. */ void assign_resources(struct bus *bus) { struct device *curdev; printk(BIOS_SPEW, "%s assign_resources, bus %d link: %d\n", dev_path(bus->dev), bus->secondary, bus->link_num); for (curdev = bus->children; curdev; curdev = curdev->sibling) { if (!curdev->enabled || !curdev->resource_list) continue; if (!curdev->ops || !curdev->ops->set_resources) { printk(BIOS_ERR, "%s missing set_resources\n", dev_path(curdev)); continue; } curdev->ops->set_resources(curdev); } printk(BIOS_SPEW, "%s assign_resources, bus %d link: %d\n", dev_path(bus->dev), bus->secondary, bus->link_num); } /** * Enable the resources for devices on a link. * * Enable resources of the device by calling the device specific * enable_resources() method. * * The parent's resources should be enabled first to avoid having enabling * order problem. This is done by calling the parent's enable_resources() * method before its childrens' enable_resources() methods. * * @param link The link whose devices' resources are to be enabled. */ static void enable_resources(struct bus *link) { struct device *dev; struct bus *c_link; for (dev = link->children; dev; dev = dev->sibling) { if (dev->enabled && dev->ops && dev->ops->enable_resources) dev->ops->enable_resources(dev); } for (dev = link->children; dev; dev = dev->sibling) { for (c_link = dev->link_list; c_link; c_link = c_link->next) enable_resources(c_link); } } /** * Reset all of the devices on a bus and clear the bus's reset_needed flag. * * @param bus Pointer to the bus structure. * @return 1 if the bus was successfully reset, 0 otherwise. */ int reset_bus(struct bus *bus) { if (bus && bus->dev && bus->dev->ops && bus->dev->ops->reset_bus) { bus->dev->ops->reset_bus(bus); bus->reset_needed = 0; return 1; } return 0; } /** * Scan for devices on a bus. * * If there are bridges on the bus, recursively scan the buses behind the * bridges. If the setting up and tuning of the bus causes a reset to be * required, reset the bus and scan it again. * * @param busdev Pointer to the bus device. * @param max Current bus number. * @return The maximum bus number found, after scanning all subordinate buses. */ unsigned int scan_bus(struct device *busdev, unsigned int max) { unsigned int new_max; int do_scan_bus; if (!busdev || !busdev->enabled || !busdev->ops || !busdev->ops->scan_bus) { return max; } do_scan_bus = 1; while (do_scan_bus) { struct bus *link; new_max = busdev->ops->scan_bus(busdev, max); do_scan_bus = 0; for (link = busdev->link_list; link; link = link->next) { if (link->reset_needed) { if (reset_bus(link)) do_scan_bus = 1; else busdev->bus->reset_needed = 1; } } } return new_max; } /** * Determine the existence of devices and extend the device tree. * * Most of the devices in the system are listed in the mainboard devicetree.cb * file. The device structures for these devices are generated at compile * time by the config tool and are organized into the device tree. This * function determines if the devices created at compile time actually exist * in the physical system. * * For devices in the physical system but not listed in devicetree.cb, * the device structures have to be created at run time and attached to the * device tree. * * This function starts from the root device 'dev_root', scans the buses in * the system recursively, and modifies the device tree according to the * result of the probe. * * This function has no idea how to scan and probe buses and devices at all. * It depends on the bus/device specific scan_bus() method to do it. The * scan_bus() method also has to create the device structure and attach * it to the device tree. */ void dev_enumerate(void) { struct device *root; printk(BIOS_INFO, "Enumerating buses...\n"); root = &dev_root; show_all_devs(BIOS_SPEW, "Before device enumeration."); printk(BIOS_SPEW, "Compare with tree...\n"); show_devs_tree(root, BIOS_SPEW, 0, 0); if (root->chip_ops && root->chip_ops->enable_dev) root->chip_ops->enable_dev(root); if (!root->ops || !root->ops->scan_bus) { printk(BIOS_ERR, "dev_root missing scan_bus operation"); return; } scan_bus(root, 0); printk(BIOS_INFO, "done\n"); } /** * Configure devices on the devices tree. * * Starting at the root of the device tree, travel it recursively in two * passes. In the first pass, we compute and allocate resources (ranges) * requried by each device. In the second pass, the resources ranges are * relocated to their final position and stored to the hardware. * * I/O resources grow upward. MEM resources grow downward. * * Since the assignment is hierarchical we set the values into the dev_root * struct. */ void dev_configure(void) { struct resource *res; struct device *root; struct device *child; set_vga_bridge_bits(); printk(BIOS_INFO, "Allocating resources...\n"); root = &dev_root; /* * Each domain should create resources which contain the entire address * space for IO, MEM, and PREFMEM resources in the domain. The * allocation of device resources will be done from this address space. */ /* Read the resources for the entire tree. */ printk(BIOS_INFO, "Reading resources...\n"); read_resources(root->link_list); printk(BIOS_INFO, "Done reading resources.\n"); print_resource_tree(root, BIOS_SPEW, "After reading."); /* Compute resources for all domains. */ for (child = root->link_list->children; child; child = child->sibling) { if (!(child->path.type == DEVICE_PATH_PCI_DOMAIN)) continue; for (res = child->resource_list; res; res = res->next) { if (res->flags & IORESOURCE_FIXED) continue; if (res->flags & IORESOURCE_PREFETCH) { compute_resources(child->link_list, res, MEM_MASK, PREF_TYPE); continue; } if (res->flags & IORESOURCE_MEM) { compute_resources(child->link_list, res, MEM_MASK, MEM_TYPE); continue; } if (res->flags & IORESOURCE_IO) { compute_resources(child->link_list, res, IO_MASK, IO_TYPE); continue; } } } /* For all domains. */ for (child = root->link_list->children; child; child=child->sibling) if (child->path.type == DEVICE_PATH_PCI_DOMAIN) avoid_fixed_resources(child); /* * Now we need to adjust the resources. MEM resources need to start at * the highest address managable. */ for (child = root->link_list->children; child; child = child->sibling) { if (child->path.type != DEVICE_PATH_PCI_DOMAIN) continue; for (res = child->resource_list; res; res = res->next) { if (!(res->flags & IORESOURCE_MEM) || res->flags & IORESOURCE_FIXED) continue; res->base = resource_max(res); } } /* Store the computed resource allocations into device registers ... */ printk(BIOS_INFO, "Setting resources...\n"); for (child = root->link_list->children; child; child = child->sibling) { if (!(child->path.type == DEVICE_PATH_PCI_DOMAIN)) continue; for (res = child->resource_list; res; res = res->next) { if (res->flags & IORESOURCE_FIXED) continue; if (res->flags & IORESOURCE_PREFETCH) { allocate_resources(child->link_list, res, MEM_MASK, PREF_TYPE); continue; } if (res->flags & IORESOURCE_MEM) { allocate_resources(child->link_list, res, MEM_MASK, MEM_TYPE); continue; } if (res->flags & IORESOURCE_IO) { allocate_resources(child->link_list, res, IO_MASK, IO_TYPE); continue; } } } assign_resources(root->link_list); printk(BIOS_INFO, "Done setting resources.\n"); print_resource_tree(root, BIOS_SPEW, "After assigning values."); printk(BIOS_INFO, "Done allocating resources.\n"); } /** * Enable devices on the device tree. * * Starting at the root, walk the tree and enable all devices/bridges by * calling the device's enable_resources() method. */ void dev_enable(void) { struct bus *link; printk(BIOS_INFO, "Enabling resources...\n"); /* Now enable everything. */ for (link = dev_root.link_list; link; link = link->next) enable_resources(link); printk(BIOS_INFO, "done.\n"); } /** * Initialize a specific device. * * The parent should be initialized first to avoid having an ordering problem. * This is done by calling the parent's init() method before its childrens' * init() methods. * * @param dev The device to be initialized. */ static void init_dev(struct device *dev) { if (!dev->enabled) return; if (!dev->initialized && dev->ops && dev->ops->init) { if (dev->path.type == DEVICE_PATH_I2C) { printk(BIOS_DEBUG, "smbus: %s[%d]->", dev_path(dev->bus->dev), dev->bus->link_num); } printk(BIOS_DEBUG, "%s init\n", dev_path(dev)); dev->initialized = 1; dev->ops->init(dev); } } static void init_link(struct bus *link) { struct device *dev; struct bus *c_link; for (dev = link->children; dev; dev = dev->sibling) init_dev(dev); for (dev = link->children; dev; dev = dev->sibling) { for (c_link = dev->link_list; c_link; c_link = c_link->next) init_link(c_link); } } /** * Initialize all devices in the global device tree. * * Starting at the root device, call the device's init() method to do * device-specific setup, then call each child's init() method. */ void dev_initialize(void) { struct bus *link; printk(BIOS_INFO, "Initializing devices...\n"); #if CONFIG_ARCH_X86 /* Ensure EBDA is prepared before Option ROMs. */ setup_default_ebda(); #endif /* First call the mainboard init. */ init_dev(&dev_root); /* Now initialize everything. */ for (link = dev_root.link_list; link; link = link->next) init_link(link); printk(BIOS_INFO, "Devices initialized\n"); show_all_devs(BIOS_SPEW, "After init."); }