text: /*
   * pcie_host.c
   * utility functions for pci express host bridge.
   *
   * Copyright (c) 2009 Isaku Yamahata <yamahata at valinux co jp>
   *                    VA Linux Systems Japan K.K.
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
  
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
  
   * You should have received a copy of the GNU General Public License along
   * with this program; if not, see <http://www.gnu.org/licenses/>.
   */
  
  #include "qemu/osdep.h"
  #include "hw/pci/pci.h"
  #include "hw/pci/pcie_host.h"
  #include "qemu/module.h"
  #include "exec/address-spaces.h"
  
  /* a helper function to get a PCIDevice for a given mmconfig address */
  static inline PCIDevice *pcie_dev_find_by_mmcfg_addr(PCIBus *s,
                                                       uint32_t mmcfg_addr)
  {
      return pci_find_device(s, PCIE_MMCFG_BUS(mmcfg_addr),
                             PCIE_MMCFG_DEVFN(mmcfg_addr));
  }
  
  static void pcie_mmcfg_data_write(void *opaque, hwaddr mmcfg_addr,
                                    uint64_t val, unsigned len)
  {
      PCIExpressHost *e = opaque;
      PCIBus *s = e->pci.bus;
      PCIDevice *pci_dev = pcie_dev_find_by_mmcfg_addr(s, mmcfg_addr);
      uint32_t addr;
      uint32_t limit;
  
      if (!pci_dev) {
          return;
      }
      addr = PCIE_MMCFG_CONFOFFSET(mmcfg_addr);
      limit = pci_config_size(pci_dev);
      pci_host_config_write_common(pci_dev, addr, limit, val, len);
  }
  
  static uint64_t pcie_mmcfg_data_read(void *opaque,
                                       hwaddr mmcfg_addr,
                                       unsigned len)
  {
      PCIExpressHost *e = opaque;
      PCIBus *s = e->pci.bus;
      PCIDevice *pci_dev = pcie_dev_find_by_mmcfg_addr(s, mmcfg_addr);
      uint32_t addr;
      uint32_t limit;
  
      if (!pci_dev) {
          return ~0x0;
      }
      addr = PCIE_MMCFG_CONFOFFSET(mmcfg_addr);
      limit = pci_config_size(pci_dev);
      return pci_host_config_read_common(pci_dev, addr, limit, len);
  }
  
  static const MemoryRegionOps pcie_mmcfg_ops = {
      .read = pcie_mmcfg_data_read,
      .write = pcie_mmcfg_data_write,
      .endianness = DEVICE_LITTLE_ENDIAN,
  };
  
  static void pcie_host_init(Object *obj)
  {
      PCIExpressHost *e = PCIE_HOST_BRIDGE(obj);
  
      e->base_addr = PCIE_BASE_ADDR_UNMAPPED;
      memory_region_init_io(&e->mmio, OBJECT(e), &pcie_mmcfg_ops, e, "pcie-mmcfg-mmio",
                            PCIE_MMCFG_SIZE_MAX);
  }
  
  void pcie_host_mmcfg_unmap(PCIExpressHost *e)
  {
      if (e->base_addr != PCIE_BASE_ADDR_UNMAPPED) {
          memory_region_del_subregion(get_system_memory(), &e->mmio);
          e->base_addr = PCIE_BASE_ADDR_UNMAPPED;
      }
  }
  
  void pcie_host_mmcfg_init(PCIExpressHost *e, uint32_t size)
  {
      assert(!(size & (size - 1)));       /* power of 2 */
      assert(size >= PCIE_MMCFG_SIZE_MIN);
      assert(size <= PCIE_MMCFG_SIZE_MAX);
      e->size = size;
      memory_region_set_size(&e->mmio, e->size);
  }
  
  void pcie_host_mmcfg_map(PCIExpressHost *e, hwaddr addr,
                           uint32_t size)
  {
      pcie_host_mmcfg_init(e, size);
      e->base_addr = addr;
      memory_region_add_subregion(get_system_memory(), e->base_addr, &e->mmio);
  }
  
  void pcie_host_mmcfg_update(PCIExpressHost *e,
                              int enable,
                              hwaddr addr,
                              uint32_t size)
  {
      memory_region_transaction_begin();
      pcie_host_mmcfg_unmap(e);
      if (enable) {
          pcie_host_mmcfg_map(e, addr, size);
      }
      memory_region_transaction_commit();
  }
  
  static const TypeInfo pcie_host_type_info = {
      .name = TYPE_PCIE_HOST_BRIDGE,
      .parent = TYPE_PCI_HOST_BRIDGE,
      .abstract = true,
      .instance_size = sizeof(PCIExpressHost),
      .instance_init = pcie_host_init,
  };
  
  static void pcie_host_register_types(void)
  {
      type_register_static(&pcie_host_type_info);
  }
  
  type_init(pcie_host_register_types)
  