/* * (c) 1999--2000 Martin Mares <mj@suse.cz> * (c) 2003 Eric Biederman <ebiederm@xmission.com> * (c) 2003 Linux Networx */ /* lots of mods by ron minnich (rminnich@lanl.gov), with * the final architecture guidance from Tom Merritt (tjm@codegen.com) * 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 <console/console.h> #include <bitops.h> #include <arch/io.h> #include <device/device.h> #include <device/pci.h> #include <device/pci_ids.h> #include <stdlib.h> #include <string.h> #include <smp/spinlock.h> /** Linked list of ALL devices */ struct device *all_devices = &dev_root; /** Pointer to the last device */ extern struct device **last_dev_p; /** The upper limit of MEM resource of the devices. * Reserve 20M for the system */ #define DEVICE_MEM_HIGH 0xFEBFFFFFUL /** The lower limit of IO resource of the devices. * Reserve 4k for ISA/Legacy devices */ #define DEVICE_IO_START 0x1000 /** * @brief Allocate a new device structure. * * Allocte a new device structure and attached it to the device tree as a * child of the parent bus. * * @param parent parent bus the newly created device attached to. * @param path path to the device to be created. * * @return pointer to the newly created device structure. * * @see device_path */ static spinlock_t dev_lock = SPIN_LOCK_UNLOCKED; device_t alloc_dev(struct bus *parent, struct device_path *path) { device_t dev, child; int link; spin_lock(&dev_lock); /* 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("DEV: out of memory.\n"); } memset(dev, 0, sizeof(*dev)); memcpy(&dev->path, path, sizeof(*path)); /* Initialize the back pointers in the link fields */ for (link = 0; link < MAX_LINKS; link++) { dev->link[link].dev = dev; dev->link[link].link = link; } /* 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_p = dev; last_dev_p = &dev->next; spin_unlock(&dev_lock); return dev; } /** * @brief round a number up to an alignment. * @param val the starting value * @param roundup Alignment as a power of two * @returns 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_spew("%s read_resources bus %d link: %d\n", dev_path(bus->dev), bus->secondary, bus->link); /* Walk through all of the devices and find which resources they need. */ for (curdev = bus->children; curdev; curdev = curdev->sibling) { unsigned links; int i; if (curdev->have_resources) { continue; } if (!curdev->enabled) { continue; } if (!curdev->ops || !curdev->ops->read_resources) { printk_err("%s missing read_resources\n", dev_path(curdev)); continue; } curdev->ops->read_resources(curdev); curdev->have_resources = 1; /* Read in subtractive resources behind the current device */ links = 0; for (i = 0; i < curdev->resources; i++) { struct resource *resource; unsigned link; resource = &curdev->resource[i]; if (!(resource->flags & IORESOURCE_SUBTRACTIVE)) continue; link = IOINDEX_SUBTRACTIVE_LINK(resource->index); if (link > MAX_LINKS) { printk_err("%s subtractive index on link: %d\n", dev_path(curdev), link); continue; } if (!(links & (1 << link))) { links |= (1 << link); read_resources(&curdev->link[resource->index]); } } } printk_spew("%s read_resources bus %d link: %d done\n", dev_path(bus->dev), bus->secondary, bus->link); } 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 (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 = 0; state.result = 0; state.seen_last = 0; search_bus_resources(bus, type_mask, type, pick_largest_resource, &state); *result_res = state.result; return state.result_dev; } /* Compute allocate resources is the guts of the resource allocator. * * The problem. * - Allocate resources 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 thier 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 me 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. * */ void compute_allocate_resource( struct bus *bus, struct resource *bridge, unsigned long type_mask, unsigned long type) { struct device *dev; struct resource *resource; resource_t base; unsigned long align, min_align; min_align = 0; base = bridge->base; printk_spew("%s compute_allocate_%s: base: %08Lx size: %08Lx align: %d gran: %d\n", dev_path(bus->dev), (bridge->flags & IORESOURCE_IO)? "io": (bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem", base, bridge->size, bridge->align, bridge->gran); /* We want different minimum alignments for different kinds of * resources. These minimums are not device type specific * but resource type specific. */ if (bridge->flags & IORESOURCE_IO) { min_align = log2(DEVICE_IO_ALIGN); } if (bridge->flags & IORESOURCE_MEM) { min_align = log2(DEVICE_MEM_ALIGN); } /* Make certain I have read in all of the resources */ read_resources(bus); /* Remember I haven't found anything yet. */ resource = 0; /* Walk through all the devices on the current bus and * compute the addresses. */ while ((dev = largest_resource(bus, &resource, type_mask, type))) { resource_t size; /* Do NOT I repeat do not ignore resources which have zero size. * If they need to be ignored dev->read_resources should not even * return them. Some resources must be set even when they have * no size. PCI bridge resources are a good example of this. */ /* Propogate the resource alignment to the bridge register */ if (resource->align > bridge->align) { bridge->align = resource->align; } /* Make certain we are dealing with a good minimum size */ size = resource->size; align = resource->align; if (align < min_align) { align = min_align; } if (resource->flags & IORESOURCE_FIXED) { continue; } /* Propogate the resource limit to the bridge register */ if (bridge->limit > resource->limit) { bridge->limit = resource->limit; } /* Artificially deny limits between DEVICE_MEM_HIGH and 0xffffffff */ if ((bridge->limit > DEVICE_MEM_HIGH) && (bridge->limit <= 0xffffffff)) { bridge->limit = DEVICE_MEM_HIGH; } 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 100h - 3ffh. Therefor, only 0 - ff * can be used out of each 400h block of io * space. */ if ((base & 0x300) != 0) { base = (base & ~0x3ff) + 0x400; } /* Don't allow allocations in the VGA IO range. * PCI has special cases for that. */ else if ((base >= 0x3b0) && (base <= 0x3df)) { base = 0x3e0; } } if (((round(base, align) + size) -1) <= resource->limit) { /* base must be aligned to size */ base = round(base, align); resource->base = base; resource->flags |= IORESOURCE_ASSIGNED; resource->flags &= ~IORESOURCE_STORED; base += size; printk_spew("%s %02x * [0x%08Lx - 0x%08Lx] %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) - bridge->base; printk_spew("%s compute_allocate_%s: base: %08Lx size: %08Lx align: %d gran: %d done\n", dev_path(bus->dev), (bridge->flags & IORESOURCE_IO)? "io": (bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem", base, bridge->size, bridge->align, bridge->gran); } #if CONFIG_CONSOLE_VGA == 1 device_t vga_pri = 0; static void allocate_vga_resource(void) { #warning "FIXME modify allocate_vga_resource so it is less pci centric!" #warning "This function knows to much about PCI stuff, it should be just a ietrator/visitor." /* FIXME handle the VGA pallette snooping */ struct device *dev, *vga, *vga_onboard; struct bus *bus; bus = 0; vga = 0; vga_onboard = 0; for (dev = all_devices; dev; dev = dev->next) { if ( !dev->enabled ) continue; if (((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) && ((dev->class >> 8) != PCI_CLASS_DISPLAY_OTHER)) { if (!vga) { if (dev->on_mainboard) { vga_onboard = dev; } else { vga = dev; } } /* It isn't safe to enable other VGA cards */ dev->command &= ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO); } } if (!vga) { vga = vga_onboard; } if (vga) { // vga is first add on card or the only onboard vga printk_debug("Allocating VGA resource %s\n", dev_path(vga)); 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_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; } } #endif /** * @brief Assign the computed resources to the devices on the bus. * * @param bus Pointer to the structure for this 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() */ void assign_resources(struct bus *bus) { struct device *curdev; printk_spew("%s assign_resources, bus %d link: %d\n", dev_path(bus->dev), bus->secondary, bus->link); for (curdev = bus->children; curdev; curdev = curdev->sibling) { if (!curdev->enabled || !curdev->resources) { continue; } if (!curdev->ops || !curdev->ops->set_resources) { printk_err("%s missing set_resources\n", dev_path(curdev)); continue; } curdev->ops->set_resources(curdev); } printk_spew("%s assign_resources, bus %d link: %d\n", dev_path(bus->dev), bus->secondary, bus->link); } /** * @brief Enable the resources for a specific device * * @param dev the device whose resources are to be enabled * * 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 and let that method to call it's children's enable_resoruces() * method via the (global) enable_childrens_resources(). * * Indirect mutual recursion: * enable_resources() -> device_operations::enable_resource() * device_operations::enable_resource() -> enable_children_resources() * enable_children_resources() -> enable_resources() */ void enable_resources(struct device *dev) { if (!dev->enabled) { return; } if (!dev->ops || !dev->ops->enable_resources) { printk_err("%s missing enable_resources\n", dev_path(dev)); return; } dev->ops->enable_resources(dev); } /** * @brief Determine the existence of devices and extend the device tree. * * Most of the devices in the system are listed in the mainboard Config.lb * 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 the Config.lb file, * 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', scan the buses in * the system recursively, modify 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; unsigned subordinate; printk_info("Enumerating buses...\n"); root = &dev_root; if (root->chip_ops && root->chip_ops->enable_dev) { root->chip_ops->enable_dev(root); } if (!root->ops || !root->ops->scan_bus) { printk_err("dev_root missing scan_bus operation"); return; } subordinate = root->ops->scan_bus(root, 0); printk_info("done\n"); } /** * @brief 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 start at DEVICE_IO_START and grow upward. MEM resources start * at DEVICE_MEM_START and grow downward. * * Since the assignment is hierarchical we set the values into the dev_root * struct. */ void dev_configure(void) { struct resource *io, *mem; struct device *root; printk_info("Allocating resources...\n"); root = &dev_root; if (!root->ops || !root->ops->read_resources) { printk_err("dev_root missing read_resources\n"); return; } if (!root->ops || !root->ops->set_resources) { printk_err("dev_root missing set_resources\n"); return; } printk_info("Reading resources...\n"); root->ops->read_resources(root); printk_info("Done reading resources.\n"); /* Get the resources */ io = &root->resource[0]; mem = &root->resource[1]; /* Make certain the io devices are allocated somewhere safe. */ io->base = DEVICE_IO_START; io->flags |= IORESOURCE_ASSIGNED; io->flags &= ~IORESOURCE_STORED; /* Now reallocate the pci resources memory with the * highest addresses I can manage. */ mem->base = resource_max(&root->resource[1]); mem->flags |= IORESOURCE_ASSIGNED; mem->flags &= ~IORESOURCE_STORED; #if CONFIG_CONSOLE_VGA == 1 /* Allocate the VGA I/O resource.. */ allocate_vga_resource(); #endif /* Store the computed resource allocations into device registers ... */ printk_info("Setting resources...\n"); root->ops->set_resources(root); printk_info("Done setting resources.\n"); #if 0 mem->flags |= IORESOURCE_STORED; report_resource_stored(root, mem, ""); #endif printk_info("Done allocating resources.\n"); } /** * @brief 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) { printk_info("Enabling resourcess...\n"); /* now enable everything. */ enable_resources(&dev_root); printk_info("done.\n"); } /** * @brief Initialize all devices in the global device list. * * Starting at the first device on the global device link list, * walk the list and call the device's init() method to do deivce * specific setup. */ void dev_initialize(void) { struct device *dev; printk_info("Initializing devices...\n"); for (dev = all_devices; dev; dev = dev->next) { if (dev->enabled && !dev->initialized && dev->ops && dev->ops->init) { printk_debug("%s init\n", dev_path(dev)); dev->initialized = 1; dev->ops->init(dev); } } printk_info("Devices initialized\n"); }