| /* SPDX-License-Identifier: GPL-2.0-only */ |
| |
| #include <console/console.h> |
| #include <device/device.h> |
| #include <post.h> |
| |
| /** |
| * Round a number up to an alignment. |
| * |
| * @param val The starting value. |
| * @param pow 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; |
| } |
| |
| static const char *resource2str(struct resource *res) |
| { |
| if (res->flags & IORESOURCE_IO) |
| return "io"; |
| if (res->flags & IORESOURCE_PREFETCH) |
| return "prefmem"; |
| if (res->flags & IORESOURCE_MEM) |
| return "mem"; |
| return "undefined"; |
| } |
| |
| /** |
| * 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) |
| { |
| const struct device *dev; |
| struct resource *resource; |
| resource_t base; |
| base = round(bridge->base, bridge->align); |
| |
| if (!bus) |
| return; |
| |
| printk(BIOS_SPEW, "%s %s: base: %llx size: %llx align: %d gran: %d" |
| " limit: %llx\n", dev_path(bus->dev), resource2str(bridge), |
| 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, |
| resource2str(resource)); |
| } |
| |
| /* |
| * 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->size = round(base, bridge->gran) - |
| round(bridge->base, bridge->align); |
| |
| printk(BIOS_SPEW, "%s %s: base: %llx size: %llx align: %d gran: %d" |
| " limit: %llx done\n", dev_path(bus->dev), |
| resource2str(bridge), |
| 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) |
| { |
| const struct device *dev; |
| struct resource *resource; |
| resource_t base; |
| base = bridge->base; |
| |
| if (!bus) |
| return; |
| |
| printk(BIOS_SPEW, "%s %s: base:%llx size:%llx align:%d gran:%d " |
| "limit:%llx\n", dev_path(bus->dev), |
| resource2str(bridge), |
| 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) |
| 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->limit = resource->base + resource->size - 1; |
| 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, |
| resource2str(resource)); |
| } |
| |
| printk(BIOS_SPEW, "%s %02lx * [0x%llx - 0x%llx] %s\n", |
| dev_path(dev), resource->index, resource->base, |
| resource->size ? resource->base + resource->size - 1 : |
| resource->base, resource2str(resource)); |
| } |
| |
| /* |
| * 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: next_base: %llx size: %llx align: %d " |
| "gran: %d done\n", dev_path(bus->dev), |
| resource2str(bridge), 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)); |
| } |
| } |
| } |
| |
| static int resource_is(struct resource *res, u32 type) |
| { |
| return (res->flags & IORESOURCE_TYPE_MASK) == type; |
| } |
| |
| struct constraints { |
| struct resource io, mem; |
| }; |
| |
| static struct resource *resource_limit(struct constraints *limits, |
| struct resource *res) |
| { |
| struct resource *lim = NULL; |
| |
| /* MEM, or I/O - skip any others. */ |
| if (resource_is(res, IORESOURCE_MEM)) |
| lim = &limits->mem; |
| else if (resource_is(res, IORESOURCE_IO)) |
| lim = &limits->io; |
| |
| return lim; |
| } |
| |
| static void constrain_resources(const struct device *dev, |
| struct constraints* limits) |
| { |
| const struct device *child; |
| struct resource *res; |
| struct resource *lim; |
| struct bus *link; |
| |
| /* 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; |
| } |
| |
| lim = resource_limit(limits, res); |
| if (!lim) |
| 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; |
| |
| printk(BIOS_SPEW, "%s: %s %02lx base %08llx limit %08llx %s (fixed)\n", |
| __func__, dev_path(dev), res->index, res->base, |
| res->base + res->size - 1, resource2str(res)); |
| |
| /* |
| * 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(const struct device *dev) |
| { |
| struct constraints limits; |
| struct resource *res; |
| struct resource *lim; |
| |
| printk(BIOS_SPEW, "%s: %s\n", __func__, dev_path(dev)); |
| |
| /* Initialize constraints to maximum size. */ |
| 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); |
| |
| lim = resource_limit(&limits, res); |
| if (!lim) |
| continue; |
| |
| if (res->base > lim->base) |
| lim->base = res->base; |
| if (res->limit < lim->limit) |
| lim->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) { |
| if ((res->flags & IORESOURCE_FIXED)) |
| continue; |
| |
| lim = resource_limit(&limits, res); |
| if (!lim) |
| continue; |
| |
| /* Is the resource outside the limits? */ |
| if (lim->base > res->base) |
| res->base = lim->base; |
| if (res->limit > lim->limit) |
| res->limit = lim->limit; |
| |
| /* MEM resources need to start at the highest address manageable. */ |
| if (res->flags & IORESOURCE_MEM) |
| res->base = resource_max(res); |
| |
| printk(BIOS_SPEW, "%s:@%s %02lx base %08llx limit %08llx\n", |
| __func__, dev_path(dev), res->index, res->base, res->limit); |
| } |
| } |
| |
| void allocate_resources(const struct device *root) |
| { |
| struct resource *res; |
| const struct device *child; |
| |
| /* Compute resources for all domains. */ |
| for (child = root->link_list->children; child; child = child->sibling) { |
| if (!(child->path.type == DEVICE_PATH_DOMAIN)) |
| continue; |
| post_log_path(child); |
| for (res = child->resource_list; res; res = res->next) { |
| if (res->flags & IORESOURCE_FIXED) |
| continue; |
| if (res->flags & IORESOURCE_MEM) { |
| compute_resources(child->link_list, |
| res, IORESOURCE_TYPE_MASK, IORESOURCE_MEM); |
| continue; |
| } |
| if (res->flags & IORESOURCE_IO) { |
| compute_resources(child->link_list, |
| res, IORESOURCE_TYPE_MASK, IORESOURCE_IO); |
| continue; |
| } |
| } |
| } |
| |
| /* For all domains. */ |
| for (child = root->link_list->children; child; child=child->sibling) |
| if (child->path.type == DEVICE_PATH_DOMAIN) |
| avoid_fixed_resources(child); |
| |
| /* 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_DOMAIN)) |
| continue; |
| post_log_path(child); |
| for (res = child->resource_list; res; res = res->next) { |
| if (res->flags & IORESOURCE_FIXED) |
| continue; |
| if (res->flags & IORESOURCE_MEM) { |
| __allocate_resources(child->link_list, |
| res, IORESOURCE_TYPE_MASK, IORESOURCE_MEM); |
| continue; |
| } |
| if (res->flags & IORESOURCE_IO) { |
| __allocate_resources(child->link_list, |
| res, IORESOURCE_TYPE_MASK, IORESOURCE_IO); |
| continue; |
| } |
| } |
| } |
| } |