| /* |
| * (c) 1999--2000 Martin Mares <mj@suse.cz> |
| * (c) 2003 Eric Biederman <ebiederm@xmission.com> |
| */ |
| /* 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> |
| |
| /** |
| * This is the root of the device tree. A PCI tree always has |
| * one bus, bus 0. Bus 0 contains devices and bridges. |
| */ |
| struct device dev_root; |
| /* Linked list of ALL devices */ |
| struct device *all_devices = 0; |
| /* pointer to the last device */ |
| static struct device **last_dev_p = &all_devices; |
| |
| #define DEVICE_MEM_HIGH 0xFEC00000UL /* Reserve 20M for the system */ |
| #define DEVICE_IO_START 0x1000 |
| |
| |
| /* Append a new device to the global device chain. |
| * The chain is used to find devices once everything is set up. |
| */ |
| void append_device(struct device *dev) |
| { |
| *last_dev_p = dev; |
| last_dev_p = &dev->next; |
| } |
| |
| |
| /** round a number to an alignment. |
| * @param val the starting value |
| * @param roundup Alignment as a power of two |
| * @returns rounded up number |
| */ |
| static unsigned long round(unsigned long val, unsigned long roundup) |
| { |
| /* ROUNDUP MUST BE A POWER OF TWO. */ |
| unsigned long inverse; |
| inverse = ~(roundup - 1); |
| val += (roundup - 1); |
| val &= inverse; |
| return val; |
| } |
| |
| static unsigned long round_down(unsigned long val, unsigned long round_down) |
| { |
| /* ROUND_DOWN MUST BE A POWER OF TWO. */ |
| unsigned long inverse; |
| inverse = ~(round_down - 1); |
| val &= inverse; |
| 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 device *bus) |
| { |
| struct device *curdev; |
| |
| |
| /* Walk through all of the devices and find which resources they need. */ |
| for(curdev = bus->children; curdev; curdev = curdev->sibling) { |
| if (curdev->resources > 0) { |
| continue; |
| } |
| curdev->ops->read_resources(curdev); |
| } |
| } |
| |
| static struct device *largest_resource(struct device *bus, struct resource **result_res, |
| unsigned long type_mask, unsigned long type) |
| { |
| struct device *curdev; |
| struct device *result_dev = 0; |
| struct resource *last = *result_res; |
| struct resource *result = 0; |
| int seen_last = 0; |
| for(curdev = bus->children; curdev; curdev = curdev->sibling) { |
| int i; |
| for(i = 0; i < curdev->resources; i++) { |
| struct resource *resource = &curdev->resource[i]; |
| /* If it isn't the right kind of resource ignore it */ |
| if ((resource->flags & type_mask) != type) { |
| continue; |
| } |
| /* Be certain to pick the successor to last */ |
| if (resource == last) { |
| seen_last = 1; |
| continue; |
| } |
| if (last && ( |
| (last->align < resource->align) || |
| ((last->align == resource->align) && |
| (last->size < resource->size)) || |
| ((last->align == resource->align) && |
| (last->size == resource->size) && |
| (!seen_last)))) { |
| continue; |
| } |
| if (!result || |
| (result->align < resource->align) || |
| ((result->align == resource->align) && |
| (result->size < resource->size))) { |
| result_dev = curdev; |
| result = resource; |
| } |
| } |
| } |
| *result_res = result; |
| return 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 device *bus, |
| struct resource *bridge, |
| unsigned long type_mask, |
| unsigned long type) |
| { |
| struct device *dev; |
| struct resource *resource; |
| unsigned long base; |
| unsigned long align, min_align; |
| min_align = 0; |
| base = bridge->base; |
| |
| /* 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); |
| } |
| |
| printk_spew("DEV: %02x:%02x.%01x compute_allocate_%s: base: %08lx size: %08lx align: %d gran: %d\n", |
| bus->bus->secondary, |
| PCI_SLOT(bus->devfn), PCI_FUNC(bus->devfn), |
| (bridge->flags & IORESOURCE_IO)? "io": |
| (bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem", |
| base, bridge->size, bridge->align, bridge->gran); |
| |
| /* 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))) { |
| unsigned long 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_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, 1UL << align) + size) -1) <= resource->limit) { |
| /* base must be aligned to size */ |
| base = round(base, 1UL << align); |
| resource->base = base; |
| resource->flags |= IORESOURCE_SET; |
| base += size; |
| |
| printk_spew( |
| "DEV: %02x:%02x.%01x %02x * [0x%08lx - 0x%08lx] %s\n", |
| dev->bus->secondary, |
| PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn), |
| 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, 1UL << bridge->gran) - bridge->base; |
| |
| printk_spew("DEV: %02x:%02x.%01x compute_allocate_%s: base: %08lx size: %08lx align: %d gran: %d done\n", |
| bus->bus->secondary, |
| PCI_SLOT(bus->devfn), PCI_FUNC(bus->devfn), |
| (bridge->flags & IORESOURCE_IO)? "io": |
| (bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem", |
| base, bridge->size, bridge->align, bridge->gran); |
| |
| |
| } |
| |
| static void allocate_vga_resource(void) |
| { |
| /* FIXME handle the VGA pallette snooping */ |
| struct device *dev, *vga, *bus; |
| bus = vga = 0; |
| for(dev = all_devices; dev; dev = dev->next) { |
| uint32_t class_revision; |
| class_revision = pci_read_config32(dev, PCI_CLASS_REVISION); |
| if (((class_revision >> 24) == 0x03) && |
| ((class_revision >> 16) != 0x380)) { |
| if (!vga) { |
| printk_debug("Allocating VGA resource\n"); |
| vga = dev; |
| } |
| if (vga == dev) { |
| /* All legacy VGA cards have MEM & I/O space registers */ |
| dev->command |= PCI_COMMAND_MEMORY | PCI_COMMAND_IO; |
| } else { |
| /* It isn't safe to enable other VGA cards */ |
| dev->command &= ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO); |
| } |
| } |
| } |
| if (vga) { |
| bus = vga->bus; |
| } |
| /* Now walk up the bridges setting the VGA enable */ |
| while(bus) { |
| uint16_t ctrl; |
| ctrl = pci_read_config16(bus, PCI_BRIDGE_CONTROL); |
| ctrl |= PCI_BRIDGE_CTL_VGA; |
| pci_write_config16(bus, PCI_BRIDGE_CONTROL, ctrl); |
| bus = (bus == bus->bus)? 0 : bus->bus; |
| } |
| } |
| |
| |
| /** Assign the computed resources to the bridges and devices on the bus. |
| * Recurse to any bridges found on this bus first. Then do the devices |
| * on this bus. |
| * @param bus Pointer to the structure for this bus |
| */ |
| void assign_resources(struct device *bus) |
| { |
| struct device *curdev; |
| |
| printk_debug("ASSIGN RESOURCES, bus %d\n", bus->secondary); |
| |
| for (curdev = bus->children; curdev; curdev = curdev->sibling) { |
| curdev->ops->set_resources(curdev); |
| } |
| printk_debug("ASSIGNED RESOURCES, bus %d\n", bus->secondary); |
| } |
| |
| static void enable_resources(struct device *bus) |
| { |
| struct device *curdev; |
| |
| /* Walk through the chain of all pci devices and enable them. |
| * This is effectively a breadth first traversal so we should |
| * not have enalbing ordering problems. |
| */ |
| for (curdev = all_devices; curdev; curdev = curdev->next) { |
| uint16_t command; |
| command = pci_read_config16(curdev, PCI_COMMAND); |
| command |= curdev->command; |
| printk_debug("DEV: %02x:%02x.%01x cmd <- %02x\n", |
| curdev->bus->secondary, |
| PCI_SLOT(curdev->devfn), PCI_FUNC(curdev->devfn), |
| command); |
| pci_write_config16(curdev, PCI_COMMAND, command); |
| } |
| } |
| |
| /** Enumerate the resources on the PCI by calling pci_init |
| */ |
| void dev_enumerate(void) |
| { |
| struct device *root; |
| printk_info("Enumerating buses..."); |
| root = &dev_root; |
| if (!root->ops) { |
| root->ops = &default_pci_ops_root; |
| } |
| root->subordinate = root->ops->scan_bus(root, 0); |
| printk_info("done\n"); |
| } |
| |
| /** Starting at the root, compute what resources are needed and allocate them. |
| * I/O starts at PCI_IO_START. Since the assignment is hierarchical we |
| * set the values into the dev_root struct. |
| */ |
| void dev_configure(void) |
| { |
| struct device *root = &dev_root; |
| printk_info("Allocating resources..."); |
| printk_debug("\n"); |
| |
| |
| root->ops->read_resources(root); |
| |
| /* Make certain the io devices are allocated somewhere |
| * safe. |
| */ |
| root->resource[0].base = DEVICE_IO_START; |
| root->resource[0].flags |= IORESOURCE_SET; |
| /* Now reallocate the pci resources memory with the |
| * highest addresses I can manage. |
| */ |
| root->resource[1].base = |
| round_down(DEVICE_MEM_HIGH - root->resource[1].size, |
| 1UL << root->resource[1].align); |
| root->resource[1].flags |= IORESOURCE_SET; |
| // now just set things into registers ... we hope ... |
| root->ops->set_resources(root); |
| |
| allocate_vga_resource(); |
| |
| printk_info("done.\n"); |
| } |
| |
| /** Starting at the root, walk the tree and enable all devices/bridges. |
| * What really happens is computed COMMAND bits get set in register 4 |
| */ |
| void dev_enable(void) |
| { |
| printk_info("Enabling resourcess..."); |
| |
| /* now enable everything. */ |
| enable_resources(&dev_root); |
| printk_info("done.\n"); |
| } |
| |
| /** Starting at the root, walk the tree and call a driver to |
| * do device specific setup. |
| */ |
| void dev_initialize(void) |
| { |
| struct device *dev; |
| |
| printk_info("Initializing devices...\n"); |
| for (dev = all_devices; dev; dev = dev->next) { |
| if (dev->ops->init) { |
| printk_debug("PCI: %02x:%02x.%01x init\n", |
| dev->bus->secondary, |
| PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn)); |
| dev->ops->init(dev); |
| } |
| } |
| printk_info("Devices initialized\n"); |
| } |
| |
| |