[Qemu-devel] [RFC][PATCH] PCI: fix pci_to_cpu_addr() issue

[Huacai Chen <zltjiangshi@gmail.com>]

It seems like software may both use CPU address or PCI address to access a PCI
device. For example, Bonito north bridge map PCI memory space at 0x10000000 ~ 
0x1C000000. PMON code use 0x00000000 ~ 0x0C000000, but Linux kernel code use 
0x10000000 ~ 0x1C000000 to access devices. If set pci_mem_base to 0, PMON can't
work, but if set pci_mem_base to 0x10000000, Linux can't access PCI. So I make
this patch to make both cases works.

However, I don't know whether the modification will break other archs, so
request for comments here.

Signed-off-by: Huacai Chen <zltjiangshi@gmail.com>
---
 hw/pci.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/hw/pci.c b/hw/pci.c
index 7787005..50e3572 100644
--- a/hw/pci.c
+++ b/hw/pci.c
@@ -672,7 +672,7 @@ PCIDevice *pci_register_device(PCIBus *bus, const char *name,
 static target_phys_addr_t pci_to_cpu_addr(PCIBus *bus,
                                           target_phys_addr_t addr)
 {
-    return addr + bus->mem_base;
+    return addr | bus->mem_base;
 }
 
 static void pci_unregister_io_regions(PCIDevice *pci_dev)
-- 
1.7.0.4