On Mon, 2013-09-16 at 12:04 +0300, Michael S. Tsirkin wrote: > On Mon, Sep 16, 2013 at 11:21:16AM +0300, Marcel Apfelbaum wrote: > > A MemoryRegion with negative priority was created and > > it spans over all the pci address space. > > It "intercepts" the accesses to unassigned pci > > address space and will follow the pci spec: > > 1. returns -1 on read > > 2. does nothing on write > > > > Note: setting the RECEIVED MASTER ABORT bit in the STATUS register > > of the device that initiated the transaction will be > > implemented in another series > > > > Signed-off-by: Marcel Apfelbaum <marce...@redhat.com> > > --- > > Changes from v4: > > - Addressed Michael S. Tsirkin comments > > - Changed PCI master_abort_mem ops endian-nes to DEVICE_LITTLE_ENDIAN > > - Fixed: overlap master_abort_mem at offset 0, not at > > bus->address_space_mem.addr > > > > hw/pci/pci.c | 26 ++++++++++++++++++++++++++ > > include/hw/pci/pci_bus.h | 1 + > > 2 files changed, 27 insertions(+) > > > > diff --git a/hw/pci/pci.c b/hw/pci/pci.c > > index ad1c1ca..d8a1b11 100644 > > --- a/hw/pci/pci.c > > +++ b/hw/pci/pci.c > > @@ -283,6 +283,24 @@ const char *pci_root_bus_path(PCIDevice *dev) > > return rootbus->qbus.name; > > } > > > > +static uint64_t master_abort_mem_read(void *opaque, hwaddr addr, unsigned > > size) > > +{ > > + return -1ULL; > > +} > > + > > +static void master_abort_mem_write(void *opaque, hwaddr addr, uint64_t val, > > + unsigned size) > > +{ > > +} > > + > > +static const MemoryRegionOps master_abort_mem_ops = { > > + .read = master_abort_mem_read, > > + .write = master_abort_mem_write, > > + .endianness = DEVICE_LITTLE_ENDIAN, > > +}; > > + > > +#define MASTER_ABORT_MEM_PRIORITY INT_MIN > > + > > static void pci_bus_init(PCIBus *bus, DeviceState *parent, > > const char *name, > > MemoryRegion *address_space_mem, > > @@ -294,6 +312,14 @@ static void pci_bus_init(PCIBus *bus, DeviceState > > *parent, > > bus->address_space_mem = address_space_mem; > > bus->address_space_io = address_space_io; > > > > + > > + memory_region_init_io(&bus->master_abort_mem, OBJECT(bus), > > + &master_abort_mem_ops, bus, "pci-master-abort", > > + memory_region_size(bus->address_space_mem)); > > + memory_region_add_subregion_overlap(bus->address_space_mem, > > + 0, &bus->master_abort_mem, > > + MASTER_ABORT_MEM_PRIORITY); > > + > > /* host bridge */ > > QLIST_INIT(&bus->child); > > > > Does this handle devices behind bridges? Yes, tested also for devices behind bridge.
> > > > diff --git a/include/hw/pci/pci_bus.h b/include/hw/pci/pci_bus.h > > index 9df1788..2ad5edb 100644 > > --- a/include/hw/pci/pci_bus.h > > +++ b/include/hw/pci/pci_bus.h > > @@ -23,6 +23,7 @@ struct PCIBus { > > PCIDevice *parent_dev; > > MemoryRegion *address_space_mem; > > MemoryRegion *address_space_io; > > + MemoryRegion master_abort_mem; > > > > Looks like this field is left uninitialized for bridge > devices (they don't seem to call pci_bus_init)? The bridges have no influence with respect to master_abort_mem as it handles *all* unassigned addresses for PCI address space. As stated above, it was tested. Thanks, Marcel > > > QLIST_HEAD(, PCIBus) child; /* this will be replaced by qdev later */ > > QLIST_ENTRY(PCIBus) sibling;/* this will be replaced by qdev later */ > > -- > > 1.8.3.1