Alex,
could you ACK this patch ?
It's not perfect and it will be removed later, but for the moment it
allows to hotplug PCI card in pseries.
Laurent
On 24/07/2015 10:35, Laurent Vivier wrote:
> Some kernels program a 0 address for io regions. PCI 3.0 spec
> section 6.2.5.1 doesn't seem to disallow this.
>
> based on patch by Michael Roth <mdr...@linux.vnet.ibm.com>
>
> Add pci_allow_0_addr in MachineClass to conditionally
> allow addr 0 for pseries, as this can break other architectures.
>
> This patch allows to hotplug PCI card in pseries machine, as the first
> added card BAR0 is always set to 0 address.
>
> This as a temporary hack, waiting to fix PCI memory priorities for more
> machine types...
>
> Signed-off-by: Laurent Vivier <lviv...@redhat.com>
> ---
> v2: move flag from PCIBus to MachineClass, rename it pci_allow_0_address
> v3: change author, update commit message.
> hw/pci/pci.c | 12 +++++++++---
> hw/ppc/spapr.c | 1 +
> include/hw/boards.h | 3 ++-
> 3 files changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index a017614..9f57aea 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -38,6 +38,7 @@
> #include "hw/pci/msix.h"
> #include "exec/address-spaces.h"
> #include "hw/hotplug.h"
> +#include "hw/boards.h"
>
> //#define DEBUG_PCI
> #ifdef DEBUG_PCI
> @@ -1065,6 +1066,10 @@ static pcibus_t pci_bar_address(PCIDevice *d,
> pcibus_t new_addr, last_addr;
> int bar = pci_bar(d, reg);
> uint16_t cmd = pci_get_word(d->config + PCI_COMMAND);
> + Object *machine = qdev_get_machine();
> + ObjectClass *oc = object_get_class(machine);
> + MachineClass *mc = MACHINE_CLASS(oc);
> + bool allow_0_address = mc->pci_allow_0_address;
>
> if (type & PCI_BASE_ADDRESS_SPACE_IO) {
> if (!(cmd & PCI_COMMAND_IO)) {
> @@ -1075,7 +1080,8 @@ static pcibus_t pci_bar_address(PCIDevice *d,
> /* Check if 32 bit BAR wraps around explicitly.
> * TODO: make priorities correct and remove this work around.
> */
> - if (last_addr <= new_addr || new_addr == 0 || last_addr >=
> UINT32_MAX) {
> + if (last_addr <= new_addr || last_addr >= UINT32_MAX ||
> + (!allow_0_address && new_addr == 0)) {
> return PCI_BAR_UNMAPPED;
> }
> return new_addr;
> @@ -1099,8 +1105,8 @@ static pcibus_t pci_bar_address(PCIDevice *d,
> /* XXX: as we cannot support really dynamic
> mappings, we handle specific values as invalid
> mappings. */
> - if (last_addr <= new_addr || new_addr == 0 ||
> - last_addr == PCI_BAR_UNMAPPED) {
> + if (last_addr <= new_addr || last_addr == PCI_BAR_UNMAPPED ||
> + (!allow_0_address && new_addr == 0)) {
> return PCI_BAR_UNMAPPED;
> }
>
> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> index a6f1947..bf0c64f 100644
> --- a/hw/ppc/spapr.c
> +++ b/hw/ppc/spapr.c
> @@ -1835,6 +1835,7 @@ static void spapr_machine_class_init(ObjectClass *oc,
> void *data)
> mc->default_ram_size = 512 * M_BYTE;
> mc->kvm_type = spapr_kvm_type;
> mc->has_dynamic_sysbus = true;
> + mc->pci_allow_0_address = true;
>
> fwc->get_dev_path = spapr_get_fw_dev_path;
> nc->nmi_monitor_handler = spapr_nmi;
> diff --git a/include/hw/boards.h b/include/hw/boards.h
> index 2aec9cb..3f84afd 100644
> --- a/include/hw/boards.h
> +++ b/include/hw/boards.h
> @@ -100,7 +100,8 @@ struct MachineClass {
> no_cdrom:1,
> no_sdcard:1,
> has_dynamic_sysbus:1,
> - no_tco:1;
> + no_tco:1,
> + pci_allow_0_address:1;
> int is_default;
> const char *default_machine_opts;
> const char *default_boot_order;
>
