From e402463073ae51d00dc6cf98556e2f5c4b008a31 Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Fri, 24 Jul 2015 10:35:13 +0200 Subject: [PATCH] pci: allow 0 address for PCI IO/MEM regions 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 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 Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- 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 a017614d48..9f57aeaeba 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 a6f19473cf..bf0c64f2d4 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 2aec9cbb12..3f84afdf1c 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; -- 2.11.4.GIT