On Sun, May 15, 2016 at 10:23:32PM +0300, Marcel Apfelbaum wrote:
> Using the firmware assigned MMIO ranges for 64-bit PCI window
> leads to zero space for hot-plugging PCI devices over 4G.
>
> PC machines can use the whole CPU addressable range after
> the space reserved for memory-hotplug.
>
> Signed-off-by: Marcel Apfelbaum <mar...@redhat.com>
> ---
> hw/pci/pci.c | 16 ++++++++++++++--
> 1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index bb605ef..44dd949 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -41,6 +41,7 @@
> #include "hw/hotplug.h"
> #include "hw/boards.h"
> #include "qemu/cutils.h"
> +#include "hw/i386/pc.h"
>
> //#define DEBUG_PCI
> #ifdef DEBUG_PCI
I don't want pci to depend on PC.
Pls find another way to do this.
> @@ -2467,8 +2468,19 @@ static void pci_dev_get_w64(PCIBus *b, PCIDevice *dev,
> void *opaque)
>
> void pci_bus_get_w64_range(PCIBus *bus, Range *range)
> {
> - range->begin = range->end = 0;
> - pci_for_each_device_under_bus(bus, pci_dev_get_w64, range);
> + Object *machine = qdev_get_machine();
An empty line won't hurt here after the declaration.
> + if (object_dynamic_cast(machine, TYPE_PC_MACHINE)) {
> + PCMachineState *pcms = PC_MACHINE(machine);
An empty line won't hurt here after the declaration.
> + range->begin = pc_machine_get_reserved_memory_end(pcms);
> + if (!range->begin) {
> + range->begin = ROUND_UP(0x100000000ULL + pcms->above_4g_mem_size,
> + 1ULL << 30);
Why 30? what is the logic here?
> + }
> + range->end = 1ULL << 40; /* 40 bits physical */
This comment does not help. Physical what? And why is 40 bit right?
> + } else {
> + range->begin = range->end = 0;
> + pci_for_each_device_under_bus(bus, pci_dev_get_w64, range);
When does this trigger?
Pls add a comment.
> + }
> }
>
> static bool pcie_has_upstream_port(PCIDevice *dev)
> --
> 2.4.3
