+typedef int (*check_reserved_t)(u64 start, u64 end, unsigned type);
+
+static int __init is_mmconf_reserved(check_reserved_t is_reserved,
+ u64 addr, u64 size, int i,
+ typeof(pci_mmcfg_config[0]) *cfg, int with_e820)
+{
+ u64 old_size = size;
+ int valid = 0;
+
+ while (!is_reserved(addr, addr + size - 1, E820_RESERVED)) {
+ size >>= 1;
+ if (size < (16UL<<20))
+ break;
+ }
+
+ if (size >= (16UL<<20) || size == old_size) {
+ printk(KERN_NOTICE
+ "PCI: MCFG area at %Lx reserved in %s\n",
+ addr, with_e820?"E820":"ACPI motherboard resources");
+ valid = 1;
+
+ if (old_size != size) {
+ /* update end_bus_number */
+ cfg->end_bus_number = cfg->start_bus_number + ((size>>20) - 1);
+ printk(KERN_NOTICE "PCI: updated MCFG configuration %d: base %lx "
+ "segment %hu buses %u - %u\n",
+ i, (unsigned long)cfg->address, cfg->pci_segment,
+ (unsigned int)cfg->start_bus_number,
+ (unsigned int)cfg->end_bus_number);
+ }
+ }
+
+ return valid;
+}
+