Re: [Qemu-devel] [PATCH v5] Xen PV Device

[Anthony Liguori <anthony@codemonkey.ws>]

Paul Durrant <paul.durrant@citrix.com> writes:

> Introduces a new Xen PV PCI device which will act as a binding point for
> PV drivers for Xen.
> The device has parameterized vendor-id, device-id and revision to allow to
> be configured as a binding point for any vendor's PV drivers.
>
> Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
> Cc: Stefano Stabellini <stefano.stabellini@citrix.com>
> Reviewed-by: Andreas Färber <afaerber@suse.de>

Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>

Regards,

Anthony Liguori


> ---
>
> V5:
> - Addresses comments from Andreas Färber
>
> V4:
> - Renamed from 'Citrix PV Bus' to 'Xen PV Device'
> - Paramaterized vendor-id and device-id as requested by Stefano Stabellini
>
> V3:
> - Addresses comments from Anthony Liguori and Peter Maydell
>
> V2:
> - Addresses comments from Andreas Farber and Paolo Bonzini
>
>  hw/xen/Makefile.objs     |    1 +
>  hw/xen/xen_pvdevice.c    |  131 ++++++++++++++++++++++++++++++++++++++++++++++
>  include/hw/pci/pci_ids.h |    5 +-
>  trace-events             |    4 ++
>  4 files changed, 139 insertions(+), 2 deletions(-)
>  create mode 100644 hw/xen/xen_pvdevice.c
>
> diff --git a/hw/xen/Makefile.objs b/hw/xen/Makefile.objs
> index 2017560..cd2df6a 100644
> --- a/hw/xen/Makefile.objs
> +++ b/hw/xen/Makefile.objs
> @@ -1,5 +1,6 @@
>  # xen backend driver support
>  common-obj-$(CONFIG_XEN_BACKEND) += xen_backend.o xen_devconfig.o
> +common-obj-y += xen_pvdevice.o
>  
>  obj-$(CONFIG_XEN_I386) += xen_platform.o xen_apic.o
>  obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen-host-pci-device.o
> diff --git a/hw/xen/xen_pvdevice.c b/hw/xen/xen_pvdevice.c
> new file mode 100644
> index 0000000..93dfab2
> --- /dev/null
> +++ b/hw/xen/xen_pvdevice.c
> @@ -0,0 +1,131 @@
> +/* Copyright (c) Citrix Systems Inc.
> + * All rights reserved.
> + * 
> + * Redistribution and use in source and binary forms, 
> + * with or without modification, are permitted provided 
> + * that the following conditions are met:
> + * 
> + * *   Redistributions of source code must retain the above 
> + *     copyright notice, this list of conditions and the 
> + *     following disclaimer.
> + * *   Redistributions in binary form must reproduce the above 
> + *     copyright notice, this list of conditions and the 
> + *     following disclaimer in the documentation and/or other 
> + *     materials provided with the distribution.
> + * 
> + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
> + * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 
> + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
> + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
> + * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 
> + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
> + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
> + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
> + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
> + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
> + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
> + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
> + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 
> + * SUCH DAMAGE.
> + */
> +
> +#include "hw/hw.h"
> +#include "hw/pci/pci.h"
> +#include "trace.h"
> +
> +#define TYPE_XEN_PV_DEVICE  "xen-pvdevice"
> +
> +#define XEN_PV_DEVICE(obj) \
> +     OBJECT_CHECK(XenPVDevice, (obj), TYPE_XEN_PV_DEVICE)
> +
> +typedef struct XenPVDevice {
> +    /*< private >*/
> +    PCIDevice       parent_obj;
> +    /*< public >*/
> +    uint16_t        vendor_id;
> +    uint16_t        device_id;
> +    uint8_t         revision;
> +    uint32_t        size;
> +    MemoryRegion    mmio;
> +} XenPVDevice;
> +
> +static uint64_t xen_pv_mmio_read(void *opaque, hwaddr addr,
> +                                 unsigned size)
> +{
> +    trace_xen_pv_mmio_read(addr);
> +
> +    return ~(uint64_t)0;
> +}
> +
> +static void xen_pv_mmio_write(void *opaque, hwaddr addr,
> +                              uint64_t val, unsigned size)
> +{
> +    trace_xen_pv_mmio_write(addr);
> +}
> +
> +static const MemoryRegionOps xen_pv_mmio_ops = {
> +    .read = &xen_pv_mmio_read,
> +    .write = &xen_pv_mmio_write,
> +    .endianness = DEVICE_LITTLE_ENDIAN,
> +};
> +
> +static int xen_pv_init(PCIDevice *pci_dev)
> +{
> +    XenPVDevice *d = XEN_PV_DEVICE(pci_dev);
> +    uint8_t *pci_conf;
> +
> +    pci_conf = pci_dev->config;
> +
> +    pci_set_word(pci_conf + PCI_VENDOR_ID, d->vendor_id);
> +    pci_set_word(pci_conf + PCI_SUBSYSTEM_VENDOR_ID, d->vendor_id);
> +    pci_set_word(pci_conf + PCI_DEVICE_ID, d->device_id);
> +    pci_set_word(pci_conf + PCI_SUBSYSTEM_ID, d->device_id);
> +    pci_set_byte(pci_conf + PCI_REVISION_ID, d->revision);
> +
> +    pci_set_word(pci_conf + PCI_COMMAND, PCI_COMMAND_MEMORY);
> +
> +    pci_config_set_prog_interface(pci_conf, 0);
> +
> +    pci_conf[PCI_INTERRUPT_PIN] = 1;
> +
> +    memory_region_init_io(&d->mmio, &xen_pv_mmio_ops, d,
> +                          "mmio", d->size);
> +
> +    pci_register_bar(pci_dev, 1, PCI_BASE_ADDRESS_MEM_PREFETCH,
> +                     &d->mmio);
> +
> +    return 0;
> +}
> +
> +static Property xen_pv_props[] = {
> +    DEFINE_PROP_UINT16("vendor-id", XenPVDevice, vendor_id, PCI_VENDOR_ID_XEN),
> +    DEFINE_PROP_UINT16("device-id", XenPVDevice, device_id, PCI_DEVICE_ID_XEN_PVDEVICE),
> +    DEFINE_PROP_UINT8("revision", XenPVDevice, revision, 0x01),
> +    DEFINE_PROP_UINT32("size", XenPVDevice, size, 0x400000),
> +    DEFINE_PROP_END_OF_LIST()
> +};
> +
> +static void xen_pv_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
> +
> +    k->init = xen_pv_init;
> +    k->class_id = PCI_CLASS_SYSTEM_OTHER;
> +    dc->desc = "Xen PV Device";
> +    dc->props = xen_pv_props;
> +}
> +
> +static const TypeInfo xen_pv_type_info = {
> +    .name          = TYPE_XEN_PV_DEVICE,
> +    .parent        = TYPE_PCI_DEVICE,
> +    .instance_size = sizeof(XenPVDevice),
> +    .class_init    = xen_pv_class_init,
> +};
> +
> +static void xen_pv_register_types(void)
> +{
> +    type_register_static(&xen_pv_type_info);
> +}
> +
> +type_init(xen_pv_register_types)
> diff --git a/include/hw/pci/pci_ids.h b/include/hw/pci/pci_ids.h
> index d8dc2f1..263bca3 100644
> --- a/include/hw/pci/pci_ids.h
> +++ b/include/hw/pci/pci_ids.h
> @@ -142,8 +142,9 @@
>  
>  #define PCI_DEVICE_ID_INTEL_Q35_MCH      0x29c0
>  
> -#define PCI_VENDOR_ID_XEN               0x5853
> -#define PCI_DEVICE_ID_XEN_PLATFORM      0x0001
> +#define PCI_VENDOR_ID_XEN                0x5853
> +#define PCI_DEVICE_ID_XEN_PLATFORM       0x0001
> +#define PCI_DEVICE_ID_XEN_PVDEVICE       0x0002
>  
>  #define PCI_VENDOR_ID_NEC                0x1033
>  #define PCI_DEVICE_ID_NEC_UPD720200      0x0194
> diff --git a/trace-events b/trace-events
> index c5f1ccb..0445853 100644
> --- a/trace-events
> +++ b/trace-events
> @@ -1161,3 +1161,7 @@ kvm_run_exit(int cpu_index, uint32_t reason) "cpu_index %d, reason %d"
>  # qom/object.c
>  object_dynamic_cast_assert(const char *type, const char *target, const char *file, int line, const char *func) "%s->%s (%s:%d:%s)"
>  object_class_dynamic_cast_assert(const char *type, const char *target, const char *file, int line, const char *func) "%s->%s (%s:%d:%s)"
> +
> +# hw/xen/xen_pvdevice.c
> +xen_pv_mmio_read(uint64_t addr) "WARNING: read from Xen PV Device MMIO space (address %"PRIx64")"
> +xen_pv_mmio_write(uint64_t addr) "WARNING: write to Xen PV Device MMIO space (address %"PRIx64")"
> -- 
> 1.7.10.4