440fx: fix PAM, PCI holes

The current implementation of PAM and the PCI holes is broken in several
ways:

  - PCI BARs are not restricted to the PCI hole (a BAR may hide memory)
  - PCI devices do not respect PAM (if a PCI device maps a region while
    PAM maps the region to RAM, the request will be honored)

This patch fixes things by introducing a pci address space, and using
memory region aliases to represent PAM regions, SMRAM, and PCI holes.

The memory hierarchy looks something like

system_memory
 |
 +--- low memory alias (0-0xe0000000)
 |      |
 |      +-- ram@0
 |
 +--- high memory alias (0x100000000-EOM)
 |      |
 |      +-- ram@0xe0000000
 |
 +--- pci hole alias (end of low memory-0x100000000)
 |      |
 |      +-- pci@end-of-low-memory
 |
 |
 +--- pam[n] (0xc0000-0xc3fff etc) (when set to pci, priority 1)
 |      |
 |      +-- pci@0xc4000 etc
 |
 +--- smram (0xa0000-0xbffff) (when set to pci/vga, priority 1)
        |
        +-- pci@0xa0000 etc

ram (simple ram region)

pci
 |
 +--- BARn
 |
 +--- VGA 0xa0000-0xbffff
 |
 +--- ROMs

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 10 insertions, 3 deletions

diff --git a/hw/pc.h b/hw/pc.h
index d871fd8a62..dae736e7e4 100644
--- a/hw/pc.h
+++ b/hw/pc.h
@@ -136,7 +136,9 @@ void pc_memory_init(MemoryRegion *system_memory,
                     const char *kernel_cmdline,
                     const char *initrd_filename,
                     ram_addr_t below_4g_mem_size,
-                    ram_addr_t above_4g_mem_size);
+                    ram_addr_t above_4g_mem_size,
+                    MemoryRegion *pci_memory,
+                    MemoryRegion **ram_memory);
 qemu_irq *pc_allocate_cpu_irq(void);
 void pc_vga_init(PCIBus *pci_bus);
 void pc_basic_device_init(qemu_irq *isa_irq,
@@ -182,8 +184,13 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix_devfn,
                     qemu_irq *pic,
                     MemoryRegion *address_space_mem,
                     MemoryRegion *address_space_io,
-                    ram_addr_t ram_size);
-void i440fx_init_memory_mappings(PCII440FXState *d);
+                    ram_addr_t ram_size,
+                    target_phys_addr_t pci_hole_start,
+                    target_phys_addr_t pci_hole_size,
+                    target_phys_addr_t pci_hole64_start,
+                    target_phys_addr_t pci_hole64_size,
+                    MemoryRegion *pci_memory,
+                    MemoryRegion *ram_memory);
 
 /* piix4.c */
 extern PCIDevice *piix4_dev;