diff mbox series

[v3,01/10] hw/acpi: Add VIOT table

Message ID 20210914142004.2433568-2-jean-philippe@linaro.org (mailing list archive)
State New, archived
Headers show
Series virtio-iommu: Add ACPI support | expand

Commit Message

Jean-Philippe Brucker Sept. 14, 2021, 2:19 p.m. UTC 
Add a function that generates a Virtual I/O Translation table (VIOT),
describing the topology of paravirtual IOMMUs. The table is created when
instantiating a virtio-iommu device. It contains a virtio-iommu node and
PCI Range nodes for endpoints managed by the IOMMU. By default, a single
node describes all PCI devices. When passing the "default_bus_bypass_iommu"
machine option and "bypass_iommu" PXB option, only buses that do not
bypass the IOMMU are described by PCI Range nodes.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
---
Sizes and types are hardcoded because it will now be the default style
https://lore.kernel.org/qemu-devel/20210708154617.1538485-1-imammedo@redhat.com/
---
 hw/acpi/viot.h      |  13 +++++
 hw/acpi/viot.c      | 112 ++++++++++++++++++++++++++++++++++++++++++++
 hw/acpi/Kconfig     |   4 ++
 hw/acpi/meson.build |   1 +
 4 files changed, 130 insertions(+)
 create mode 100644 hw/acpi/viot.h
 create mode 100644 hw/acpi/viot.c

Comments

Eric Auger Sept. 16, 2021, 12:44 p.m. UTC | #1 
Hi Jean,

On 9/14/21 4:19 PM, Jean-Philippe Brucker wrote:
> Add a function that generates a Virtual I/O Translation table (VIOT),
> describing the topology of paravirtual IOMMUs. The table is created when
> instantiating a virtio-iommu device. It contains a virtio-iommu node and
> PCI Range nodes for endpoints managed by the IOMMU. By default, a single
> node describes all PCI devices. When passing the "default_bus_bypass_iommu"
> machine option and "bypass_iommu" PXB option, only buses that do not
> bypass the IOMMU are described by PCI Range nodes.
>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> ---
> Sizes and types are hardcoded because it will now be the default style
> https://lore.kernel.org/qemu-devel/20210708154617.1538485-1-imammedo@redhat.com/
> ---
>  hw/acpi/viot.h      |  13 +++++
>  hw/acpi/viot.c      | 112 ++++++++++++++++++++++++++++++++++++++++++++
>  hw/acpi/Kconfig     |   4 ++
>  hw/acpi/meson.build |   1 +
>  4 files changed, 130 insertions(+)
>  create mode 100644 hw/acpi/viot.h
>  create mode 100644 hw/acpi/viot.c
>
> diff --git a/hw/acpi/viot.h b/hw/acpi/viot.h
> new file mode 100644
> index 0000000000..4cef29a640
> --- /dev/null
> +++ b/hw/acpi/viot.h
> @@ -0,0 +1,13 @@
> +/*
> + * ACPI Virtual I/O Translation Table implementation
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#ifndef VIOT_H
> +#define VIOT_H
> +
> +void build_viot(GArray *table_data, BIOSLinker *linker,
> +                uint16_t virtio_iommu_bdf, const char *oem_id,
> +                const char *oem_table_id);
> +
> +#endif /* VIOT_H */
> diff --git a/hw/acpi/viot.c b/hw/acpi/viot.c
> new file mode 100644
> index 0000000000..e7f7605119
> --- /dev/null
> +++ b/hw/acpi/viot.c
> @@ -0,0 +1,112 @@
> +/*
> + * ACPI Virtual I/O Translation table implementation
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#include "qemu/osdep.h"
> +#include "hw/acpi/acpi.h"
> +#include "hw/acpi/aml-build.h"
> +#include "hw/acpi/viot.h"
> +#include "hw/pci/pci.h"
> +#include "hw/pci/pci_host.h"
> +
> +struct viot_pci_ranges {
> +    GArray *blob;
> +    size_t count;
> +    uint16_t output_node;
> +};
> +
> +/* Build PCI range for a given PCI host bridge */
> +static int viot_host_bridges(Object *obj, void *opaque)
nit: rename the function into something like build_pci_range_node()
which actually indicates what it does
> +{
> +    struct viot_pci_ranges *pci_ranges = opaque;
> +    GArray *blob = pci_ranges->blob;
> +
> +    if (object_dynamic_cast(obj, TYPE_PCI_HOST_BRIDGE)) {
> +        PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus;
> +
> +        if (bus && !pci_bus_bypass_iommu(bus)) {
> +            int min_bus, max_bus;
> +
> +            pci_bus_range(bus, &min_bus, &max_bus);
> +
> +            /* Type (PCI range) */
> +            build_append_int_noprefix(blob, 1, 1);
> +            /* Reserved */
> +            build_append_int_noprefix(blob, 0, 1);
> +            /* Length */
> +            build_append_int_noprefix(blob, 24, 2);
> +            /* Endpoint start */
> +            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 4);
> +            /* PCI Segment start */
> +            build_append_int_noprefix(blob, 0, 2);
> +            /* PCI Segment end */
> +            build_append_int_noprefix(blob, 0, 2);
> +            /* PCI BDF start */
> +            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 2);
> +            /* PCI BDF end */
> +            build_append_int_noprefix(blob, PCI_BUILD_BDF(max_bus, 0xff), 2);
> +            /* Output node */
> +            build_append_int_noprefix(blob, pci_ranges->output_node, 2);
> +            /* Reserved */
> +            build_append_int_noprefix(blob, 0, 6);
> +
> +            pci_ranges->count++;
> +        }
> +    }
> +
> +    return 0;
> +}
> +
> +/*
> + * Generate a VIOT table with one PCI-based virtio-iommu that manages PCI
> + * endpoints.
> + */
> +void build_viot(GArray *table_data, BIOSLinker *linker,
> +                uint16_t virtio_iommu_bdf, const char *oem_id,
> +                const char *oem_table_id)
> +{
> +    /* The virtio-iommu node follows the 48-bytes header */
> +    int viommu_off = 48;
> +    AcpiTable table = { .sig = "VIOT", .rev = 0,
> +                        .oem_id = oem_id, .oem_table_id = oem_table_id };
> +    struct viot_pci_ranges pci_ranges = {
> +        .output_node = viommu_off,
> +        .blob = g_array_new(false, true, 1),
nit add clear comment as in the other places?

.blob = g_array_new(false, /* clear */ true, 1),

> +    };
> +
> +    /* Build the list of PCI ranges that this viommu manages */
> +    object_child_foreach_recursive(object_get_root(), viot_host_bridges,
> +                                   &pci_ranges);
> +
> +    /* ACPI table header */
> +    acpi_table_begin(&table, table_data);
> +    /* Node count */
> +    build_append_int_noprefix(table_data, pci_ranges.count + 1, 2);
> +    /* Node offset */
> +    build_append_int_noprefix(table_data, viommu_off, 2);
> +    /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 8);
> +
> +    /* Virtio-iommu node */
> +    /* Type (virtio-pci IOMMU)  */
> +    build_append_int_noprefix(table_data, 3, 1);
> +    /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 1);
> +    /* Length */
> +    build_append_int_noprefix(table_data, 16, 2);
> +    /* PCI Segment */
> +    build_append_int_noprefix(table_data, 0, 2);
> +    /* PCI BDF number */
> +    build_append_int_noprefix(table_data, virtio_iommu_bdf, 2);
> +    /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 8);
> +
> +    /* PCI ranges found above */
> +    g_array_append_vals(table_data, pci_ranges.blob->data,
> +                        pci_ranges.blob->len);
> +    g_array_free(pci_ranges.blob, true);
> +
> +    acpi_table_end(linker, &table);
> +}
> +
> diff --git a/hw/acpi/Kconfig b/hw/acpi/Kconfig
> index 3b5e118c54..622b0b50b7 100644
> --- a/hw/acpi/Kconfig
> +++ b/hw/acpi/Kconfig
> @@ -51,6 +51,10 @@ config ACPI_VMGENID
>      default y
>      depends on PC
>  
> +config ACPI_VIOT
> +    bool
> +    depends on ACPI
> +
>  config ACPI_HW_REDUCED
>      bool
>      select ACPI
> diff --git a/hw/acpi/meson.build b/hw/acpi/meson.build
> index 7d8c0eb43e..adf6347bc4 100644
> --- a/hw/acpi/meson.build
> +++ b/hw/acpi/meson.build
> @@ -20,6 +20,7 @@ acpi_ss.add(when: 'CONFIG_ACPI_APEI', if_true: files('ghes.c'), if_false: files(
>  acpi_ss.add(when: 'CONFIG_ACPI_PIIX4', if_true: files('piix4.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_true: files('pcihp.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_false: files('acpi-pci-hotplug-stub.c'))
> +acpi_ss.add(when: 'CONFIG_ACPI_VIOT', if_true: files('viot.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_X86_ICH', if_true: files('ich9.c', 'tco.c'))
>  acpi_ss.add(when: 'CONFIG_IPMI', if_true: files('ipmi.c'), if_false: files('ipmi-stub.c'))
>  acpi_ss.add(when: 'CONFIG_PC', if_false: files('acpi-x86-stub.c'))
Besides
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Tested with default root bus and pxb-pci. Feel free to add
Tested-by: Eric Auger <eric.auger@redhat.com>

Thanks

Eric
Igor Mammedov Sept. 20, 2021, 8:06 a.m. UTC | #2 
On Tue, 14 Sep 2021 15:19:56 +0100
Jean-Philippe Brucker <jean-philippe@linaro.org> wrote:

> Add a function that generates a Virtual I/O Translation table (VIOT),
> describing the topology of paravirtual IOMMUs. The table is created when
> instantiating a virtio-iommu device. It contains a virtio-iommu node and
> PCI Range nodes for endpoints managed by the IOMMU. By default, a single
> node describes all PCI devices. When passing the "default_bus_bypass_iommu"
> machine option and "bypass_iommu" PXB option, only buses that do not
> bypass the IOMMU are described by PCI Range nodes.
> 
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> ---
> Sizes and types are hardcoded because it will now be the default style
> https://lore.kernel.org/qemu-devel/20210708154617.1538485-1-imammedo@redhat.com/
> ---
>  hw/acpi/viot.h      |  13 +++++
>  hw/acpi/viot.c      | 112 ++++++++++++++++++++++++++++++++++++++++++++
>  hw/acpi/Kconfig     |   4 ++
>  hw/acpi/meson.build |   1 +
>  4 files changed, 130 insertions(+)
>  create mode 100644 hw/acpi/viot.h
>  create mode 100644 hw/acpi/viot.c
> 
> diff --git a/hw/acpi/viot.h b/hw/acpi/viot.h
> new file mode 100644
> index 0000000000..4cef29a640
> --- /dev/null
> +++ b/hw/acpi/viot.h
> @@ -0,0 +1,13 @@
> +/*
> + * ACPI Virtual I/O Translation Table implementation
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#ifndef VIOT_H
> +#define VIOT_H
> +
> +void build_viot(GArray *table_data, BIOSLinker *linker,
> +                uint16_t virtio_iommu_bdf, const char *oem_id,
> +                const char *oem_table_id);
> +
> +#endif /* VIOT_H */
> diff --git a/hw/acpi/viot.c b/hw/acpi/viot.c
> new file mode 100644
> index 0000000000..e7f7605119
> --- /dev/null
> +++ b/hw/acpi/viot.c
> @@ -0,0 +1,112 @@
> +/*
> + * ACPI Virtual I/O Translation table implementation
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#include "qemu/osdep.h"
> +#include "hw/acpi/acpi.h"
> +#include "hw/acpi/aml-build.h"
> +#include "hw/acpi/viot.h"
> +#include "hw/pci/pci.h"
> +#include "hw/pci/pci_host.h"
> +
> +struct viot_pci_ranges {
> +    GArray *blob;
> +    size_t count;
> +    uint16_t output_node;
> +};
> +
> +/* Build PCI range for a given PCI host bridge */
> +static int viot_host_bridges(Object *obj, void *opaque)
> +{
> +    struct viot_pci_ranges *pci_ranges = opaque;
> +    GArray *blob = pci_ranges->blob;
> +
> +    if (object_dynamic_cast(obj, TYPE_PCI_HOST_BRIDGE)) {
> +        PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus;
> +
> +        if (bus && !pci_bus_bypass_iommu(bus)) {
> +            int min_bus, max_bus;
> +
> +            pci_bus_range(bus, &min_bus, &max_bus);
> +
> +            /* Type (PCI range) */
> +            build_append_int_noprefix(blob, 1, 1);
> +            /* Reserved */
> +            build_append_int_noprefix(blob, 0, 1);
> +            /* Length */
> +            build_append_int_noprefix(blob, 24, 2);
> +            /* Endpoint start */
> +            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 4);
> +            /* PCI Segment start */
> +            build_append_int_noprefix(blob, 0, 2);
> +            /* PCI Segment end */
> +            build_append_int_noprefix(blob, 0, 2);
> +            /* PCI BDF start */
> +            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 2);
> +            /* PCI BDF end */
> +            build_append_int_noprefix(blob, PCI_BUILD_BDF(max_bus, 0xff), 2);
> +            /* Output node */
> +            build_append_int_noprefix(blob, pci_ranges->output_node, 2);
> +            /* Reserved */
> +            build_append_int_noprefix(blob, 0, 6);
> +
> +            pci_ranges->count++;
> +        }
> +    }
> +
> +    return 0;
> +}
> +
> +/*
> + * Generate a VIOT table with one PCI-based virtio-iommu that manages PCI
> + * endpoints.

We usually put a pointer to spec/revision and chapter in it
that describes being implemented table, so reviewer would
have a reference to compare code with. Otherwise I have no
idea if implementation is correct or not.

ex: build_hmat_mpda

the same applies to viot_host_bridges

> + */
> +void build_viot(GArray *table_data, BIOSLinker *linker,
> +                uint16_t virtio_iommu_bdf, const char *oem_id,
> +                const char *oem_table_id)
> +{
> +    /* The virtio-iommu node follows the 48-bytes header */
> +    int viommu_off = 48;
> +    AcpiTable table = { .sig = "VIOT", .rev = 0,
> +                        .oem_id = oem_id, .oem_table_id = oem_table_id };
> +    struct viot_pci_ranges pci_ranges = {
> +        .output_node = viommu_off,
> +        .blob = g_array_new(false, true, 1),
> +    };
> +
> +    /* Build the list of PCI ranges that this viommu manages */
> +    object_child_foreach_recursive(object_get_root(), viot_host_bridges,
> +                                   &pci_ranges);
> +
> +    /* ACPI table header */
> +    acpi_table_begin(&table, table_data);
> +    /* Node count */
> +    build_append_int_noprefix(table_data, pci_ranges.count + 1, 2);
> +    /* Node offset */
> +    build_append_int_noprefix(table_data, viommu_off, 2);
> +    /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 8);
> +
> +    /* Virtio-iommu node */
> +    /* Type (virtio-pci IOMMU)  */
> +    build_append_int_noprefix(table_data, 3, 1);
> +    /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 1);
> +    /* Length */
> +    build_append_int_noprefix(table_data, 16, 2);
> +    /* PCI Segment */
> +    build_append_int_noprefix(table_data, 0, 2);
> +    /* PCI BDF number */
> +    build_append_int_noprefix(table_data, virtio_iommu_bdf, 2);
> +    /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 8);
> +
> +    /* PCI ranges found above */
> +    g_array_append_vals(table_data, pci_ranges.blob->data,
> +                        pci_ranges.blob->len);
> +    g_array_free(pci_ranges.blob, true);
> +
> +    acpi_table_end(linker, &table);
> +}
> +
> diff --git a/hw/acpi/Kconfig b/hw/acpi/Kconfig
> index 3b5e118c54..622b0b50b7 100644
> --- a/hw/acpi/Kconfig
> +++ b/hw/acpi/Kconfig
> @@ -51,6 +51,10 @@ config ACPI_VMGENID
>      default y
>      depends on PC
>  
> +config ACPI_VIOT
> +    bool
> +    depends on ACPI
> +
>  config ACPI_HW_REDUCED
>      bool
>      select ACPI
> diff --git a/hw/acpi/meson.build b/hw/acpi/meson.build
> index 7d8c0eb43e..adf6347bc4 100644
> --- a/hw/acpi/meson.build
> +++ b/hw/acpi/meson.build
> @@ -20,6 +20,7 @@ acpi_ss.add(when: 'CONFIG_ACPI_APEI', if_true: files('ghes.c'), if_false: files(
>  acpi_ss.add(when: 'CONFIG_ACPI_PIIX4', if_true: files('piix4.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_true: files('pcihp.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_false: files('acpi-pci-hotplug-stub.c'))
> +acpi_ss.add(when: 'CONFIG_ACPI_VIOT', if_true: files('viot.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_X86_ICH', if_true: files('ich9.c', 'tco.c'))
>  acpi_ss.add(when: 'CONFIG_IPMI', if_true: files('ipmi.c'), if_false: files('ipmi-stub.c'))
>  acpi_ss.add(when: 'CONFIG_PC', if_false: files('acpi-x86-stub.c'))
Igor Mammedov Sept. 20, 2021, 8:35 a.m. UTC | #3 
On Tue, 14 Sep 2021 15:19:56 +0100
Jean-Philippe Brucker <jean-philippe@linaro.org> wrote:

> Add a function that generates a Virtual I/O Translation table (VIOT),
> describing the topology of paravirtual IOMMUs. The table is created when
> instantiating a virtio-iommu device. It contains a virtio-iommu node and
> PCI Range nodes for endpoints managed by the IOMMU. By default, a single
> node describes all PCI devices. When passing the "default_bus_bypass_iommu"
> machine option and "bypass_iommu" PXB option, only buses that do not
> bypass the IOMMU are described by PCI Range nodes.
> 
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> ---
> Sizes and types are hardcoded because it will now be the default style
> https://lore.kernel.org/qemu-devel/20210708154617.1538485-1-imammedo@redhat.com/
> ---
>  hw/acpi/viot.h      |  13 +++++
>  hw/acpi/viot.c      | 112 ++++++++++++++++++++++++++++++++++++++++++++
>  hw/acpi/Kconfig     |   4 ++
>  hw/acpi/meson.build |   1 +
>  4 files changed, 130 insertions(+)
>  create mode 100644 hw/acpi/viot.h
>  create mode 100644 hw/acpi/viot.c
> 
> diff --git a/hw/acpi/viot.h b/hw/acpi/viot.h
> new file mode 100644
> index 0000000000..4cef29a640
> --- /dev/null
> +++ b/hw/acpi/viot.h
> @@ -0,0 +1,13 @@
> +/*
> + * ACPI Virtual I/O Translation Table implementation
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#ifndef VIOT_H
> +#define VIOT_H
> +
> +void build_viot(GArray *table_data, BIOSLinker *linker,
> +                uint16_t virtio_iommu_bdf, const char *oem_id,
> +                const char *oem_table_id);
> +
> +#endif /* VIOT_H */
> diff --git a/hw/acpi/viot.c b/hw/acpi/viot.c
> new file mode 100644
> index 0000000000..e7f7605119
> --- /dev/null
> +++ b/hw/acpi/viot.c
> @@ -0,0 +1,112 @@
> +/*
> + * ACPI Virtual I/O Translation table implementation
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#include "qemu/osdep.h"
> +#include "hw/acpi/acpi.h"
> +#include "hw/acpi/aml-build.h"
> +#include "hw/acpi/viot.h"
> +#include "hw/pci/pci.h"
> +#include "hw/pci/pci_host.h"
> +
> +struct viot_pci_ranges {
> +    GArray *blob;
> +    size_t count;
> +    uint16_t output_node;
> +};
> +
> +/* Build PCI range for a given PCI host bridge */
> +static int viot_host_bridges(Object *obj, void *opaque)
> +{
> +    struct viot_pci_ranges *pci_ranges = opaque;
> +    GArray *blob = pci_ranges->blob;
> +
> +    if (object_dynamic_cast(obj, TYPE_PCI_HOST_BRIDGE)) {
> +        PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus;
> +
> +        if (bus && !pci_bus_bypass_iommu(bus)) {
> +            int min_bus, max_bus;
> +
> +            pci_bus_range(bus, &min_bus, &max_bus);
> +
> +            /* Type (PCI range) */
> +            build_append_int_noprefix(blob, 1, 1);
> +            /* Reserved */
> +            build_append_int_noprefix(blob, 0, 1);
> +            /* Length */
> +            build_append_int_noprefix(blob, 24, 2);
> +            /* Endpoint start */
> +            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 4);
> +            /* PCI Segment start */
> +            build_append_int_noprefix(blob, 0, 2);
> +            /* PCI Segment end */
> +            build_append_int_noprefix(blob, 0, 2);
> +            /* PCI BDF start */
> +            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 2);
> +            /* PCI BDF end */
> +            build_append_int_noprefix(blob, PCI_BUILD_BDF(max_bus, 0xff), 2);
> +            /* Output node */
> +            build_append_int_noprefix(blob, pci_ranges->output_node, 2);
> +            /* Reserved */
> +            build_append_int_noprefix(blob, 0, 6);
> +
> +            pci_ranges->count++;
> +        }
> +    }
> +
> +    return 0;
> +}
> +
> +/*
> + * Generate a VIOT table with one PCI-based virtio-iommu that manages PCI
> + * endpoints.
> + */
> +void build_viot(GArray *table_data, BIOSLinker *linker,
> +                uint16_t virtio_iommu_bdf, const char *oem_id,
> +                const char *oem_table_id)
> +{
> +    /* The virtio-iommu node follows the 48-bytes header */
> +    int viommu_off = 48;
> +    AcpiTable table = { .sig = "VIOT", .rev = 0,
> +                        .oem_id = oem_id, .oem_table_id = oem_table_id };
> +    struct viot_pci_ranges pci_ranges = {
> +        .output_node = viommu_off,
> +        .blob = g_array_new(false, true, 1),
> +    };
> +
> +    /* Build the list of PCI ranges that this viommu manages */
> +    object_child_foreach_recursive(object_get_root(), viot_host_bridges,

I'd limit scope to machine and re-use one that caller
already uses.

in arm case: virt_acpi_build(VirtMachineState *vms, ...
q35: acpi_build(..., MachineState *machine)

> +                                   &pci_ranges);
> +
> +    /* ACPI table header */
> +    acpi_table_begin(&table, table_data);
> +    /* Node count */
> +    build_append_int_noprefix(table_data, pci_ranges.count + 1, 2);
> +    /* Node offset */
> +    build_append_int_noprefix(table_data, viommu_off, 2);
> +    /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 8);
> +
> +    /* Virtio-iommu node */
> +    /* Type (virtio-pci IOMMU)  */
> +    build_append_int_noprefix(table_data, 3, 1);
> +    /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 1);
> +    /* Length */
> +    build_append_int_noprefix(table_data, 16, 2);
> +    /* PCI Segment */
> +    build_append_int_noprefix(table_data, 0, 2);
> +    /* PCI BDF number */
> +    build_append_int_noprefix(table_data, virtio_iommu_bdf, 2);
> +    /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 8);
> +
> +    /* PCI ranges found above */
> +    g_array_append_vals(table_data, pci_ranges.blob->data,
> +                        pci_ranges.blob->len);
> +    g_array_free(pci_ranges.blob, true);
> +
> +    acpi_table_end(linker, &table);
> +}
> +
> diff --git a/hw/acpi/Kconfig b/hw/acpi/Kconfig
> index 3b5e118c54..622b0b50b7 100644
> --- a/hw/acpi/Kconfig
> +++ b/hw/acpi/Kconfig
> @@ -51,6 +51,10 @@ config ACPI_VMGENID
>      default y
>      depends on PC
>  
> +config ACPI_VIOT
> +    bool
> +    depends on ACPI
> +
>  config ACPI_HW_REDUCED
>      bool
>      select ACPI
> diff --git a/hw/acpi/meson.build b/hw/acpi/meson.build
> index 7d8c0eb43e..adf6347bc4 100644
> --- a/hw/acpi/meson.build
> +++ b/hw/acpi/meson.build
> @@ -20,6 +20,7 @@ acpi_ss.add(when: 'CONFIG_ACPI_APEI', if_true: files('ghes.c'), if_false: files(
>  acpi_ss.add(when: 'CONFIG_ACPI_PIIX4', if_true: files('piix4.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_true: files('pcihp.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_false: files('acpi-pci-hotplug-stub.c'))
> +acpi_ss.add(when: 'CONFIG_ACPI_VIOT', if_true: files('viot.c'))
>  acpi_ss.add(when: 'CONFIG_ACPI_X86_ICH', if_true: files('ich9.c', 'tco.c'))
>  acpi_ss.add(when: 'CONFIG_IPMI', if_true: files('ipmi.c'), if_false: files('ipmi-stub.c'))
>  acpi_ss.add(when: 'CONFIG_PC', if_false: files('acpi-x86-stub.c'))
Jean-Philippe Brucker Oct. 1, 2021, 3:30 p.m. UTC | #4 
On Mon, Sep 20, 2021 at 10:06:09AM +0200, Igor Mammedov wrote:
> > +/*
> > + * Generate a VIOT table with one PCI-based virtio-iommu that manages PCI
> > + * endpoints.
> 
> We usually put a pointer to spec/revision and chapter in it
> that describes being implemented table, so reviewer would
> have a reference to compare code with. Otherwise I have no
> idea if implementation is correct or not.

The 6.5 ACPI specification isn't out yet unfortunately, so I can't put any
reference at the moment. I don't know when it will be published. The draft
specification is here: https://jpbrucker.net/virtio-iommu/viot/viot-v9.pdf
But that's only temporary. I can make a note to add the pointers once the
spec is out.

The acpica implementation could also be used for cross-reference:
https://github.com/acpica/acpica/commit/fc4e33319c1ee08f20f5c44853dd8426643f6dfd

Thanks,
Jean

> 
> ex: build_hmat_mpda
> 
> the same applies to viot_host_bridges
>
diff mbox series

Patch

diff --git a/hw/acpi/viot.h b/hw/acpi/viot.h
new file mode 100644
index 0000000000..4cef29a640
--- /dev/null
+++ b/hw/acpi/viot.h
@@ -0,0 +1,13 @@ 
+/*
+ * ACPI Virtual I/O Translation Table implementation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef VIOT_H
+#define VIOT_H
+
+void build_viot(GArray *table_data, BIOSLinker *linker,
+                uint16_t virtio_iommu_bdf, const char *oem_id,
+                const char *oem_table_id);
+
+#endif /* VIOT_H */
diff --git a/hw/acpi/viot.c b/hw/acpi/viot.c
new file mode 100644
index 0000000000..e7f7605119
--- /dev/null
+++ b/hw/acpi/viot.c
@@ -0,0 +1,112 @@ 
+/*
+ * ACPI Virtual I/O Translation table implementation
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include "qemu/osdep.h"
+#include "hw/acpi/acpi.h"
+#include "hw/acpi/aml-build.h"
+#include "hw/acpi/viot.h"
+#include "hw/pci/pci.h"
+#include "hw/pci/pci_host.h"
+
+struct viot_pci_ranges {
+    GArray *blob;
+    size_t count;
+    uint16_t output_node;
+};
+
+/* Build PCI range for a given PCI host bridge */
+static int viot_host_bridges(Object *obj, void *opaque)
+{
+    struct viot_pci_ranges *pci_ranges = opaque;
+    GArray *blob = pci_ranges->blob;
+
+    if (object_dynamic_cast(obj, TYPE_PCI_HOST_BRIDGE)) {
+        PCIBus *bus = PCI_HOST_BRIDGE(obj)->bus;
+
+        if (bus && !pci_bus_bypass_iommu(bus)) {
+            int min_bus, max_bus;
+
+            pci_bus_range(bus, &min_bus, &max_bus);
+
+            /* Type (PCI range) */
+            build_append_int_noprefix(blob, 1, 1);
+            /* Reserved */
+            build_append_int_noprefix(blob, 0, 1);
+            /* Length */
+            build_append_int_noprefix(blob, 24, 2);
+            /* Endpoint start */
+            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 4);
+            /* PCI Segment start */
+            build_append_int_noprefix(blob, 0, 2);
+            /* PCI Segment end */
+            build_append_int_noprefix(blob, 0, 2);
+            /* PCI BDF start */
+            build_append_int_noprefix(blob, PCI_BUILD_BDF(min_bus, 0), 2);
+            /* PCI BDF end */
+            build_append_int_noprefix(blob, PCI_BUILD_BDF(max_bus, 0xff), 2);
+            /* Output node */
+            build_append_int_noprefix(blob, pci_ranges->output_node, 2);
+            /* Reserved */
+            build_append_int_noprefix(blob, 0, 6);
+
+            pci_ranges->count++;
+        }
+    }
+
+    return 0;
+}
+
+/*
+ * Generate a VIOT table with one PCI-based virtio-iommu that manages PCI
+ * endpoints.
+ */
+void build_viot(GArray *table_data, BIOSLinker *linker,
+                uint16_t virtio_iommu_bdf, const char *oem_id,
+                const char *oem_table_id)
+{
+    /* The virtio-iommu node follows the 48-bytes header */
+    int viommu_off = 48;
+    AcpiTable table = { .sig = "VIOT", .rev = 0,
+                        .oem_id = oem_id, .oem_table_id = oem_table_id };
+    struct viot_pci_ranges pci_ranges = {
+        .output_node = viommu_off,
+        .blob = g_array_new(false, true, 1),
+    };
+
+    /* Build the list of PCI ranges that this viommu manages */
+    object_child_foreach_recursive(object_get_root(), viot_host_bridges,
+                                   &pci_ranges);
+
+    /* ACPI table header */
+    acpi_table_begin(&table, table_data);
+    /* Node count */
+    build_append_int_noprefix(table_data, pci_ranges.count + 1, 2);
+    /* Node offset */
+    build_append_int_noprefix(table_data, viommu_off, 2);
+    /* Reserved */
+    build_append_int_noprefix(table_data, 0, 8);
+
+    /* Virtio-iommu node */
+    /* Type (virtio-pci IOMMU)  */
+    build_append_int_noprefix(table_data, 3, 1);
+    /* Reserved */
+    build_append_int_noprefix(table_data, 0, 1);
+    /* Length */
+    build_append_int_noprefix(table_data, 16, 2);
+    /* PCI Segment */
+    build_append_int_noprefix(table_data, 0, 2);
+    /* PCI BDF number */
+    build_append_int_noprefix(table_data, virtio_iommu_bdf, 2);
+    /* Reserved */
+    build_append_int_noprefix(table_data, 0, 8);
+
+    /* PCI ranges found above */
+    g_array_append_vals(table_data, pci_ranges.blob->data,
+                        pci_ranges.blob->len);
+    g_array_free(pci_ranges.blob, true);
+
+    acpi_table_end(linker, &table);
+}
+
diff --git a/hw/acpi/Kconfig b/hw/acpi/Kconfig
index 3b5e118c54..622b0b50b7 100644
--- a/hw/acpi/Kconfig
+++ b/hw/acpi/Kconfig
@@ -51,6 +51,10 @@  config ACPI_VMGENID
     default y
     depends on PC
 
+config ACPI_VIOT
+    bool
+    depends on ACPI
+
 config ACPI_HW_REDUCED
     bool
     select ACPI
diff --git a/hw/acpi/meson.build b/hw/acpi/meson.build
index 7d8c0eb43e..adf6347bc4 100644
--- a/hw/acpi/meson.build
+++ b/hw/acpi/meson.build
@@ -20,6 +20,7 @@  acpi_ss.add(when: 'CONFIG_ACPI_APEI', if_true: files('ghes.c'), if_false: files(
 acpi_ss.add(when: 'CONFIG_ACPI_PIIX4', if_true: files('piix4.c'))
 acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_true: files('pcihp.c'))
 acpi_ss.add(when: 'CONFIG_ACPI_PCIHP', if_false: files('acpi-pci-hotplug-stub.c'))
+acpi_ss.add(when: 'CONFIG_ACPI_VIOT', if_true: files('viot.c'))
 acpi_ss.add(when: 'CONFIG_ACPI_X86_ICH', if_true: files('ich9.c', 'tco.c'))
 acpi_ss.add(when: 'CONFIG_IPMI', if_true: files('ipmi.c'), if_false: files('ipmi-stub.c'))
 acpi_ss.add(when: 'CONFIG_PC', if_false: files('acpi-x86-stub.c'))