Re: [PATCH v3 29/35] acpi: arm/virt: convert build_iort() to endian agnostic build_append_FOO() API

[Eric Auger]

On 9/7/21 4:48 PM, Igor Mammedov wrote:
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> ---
> v3:
>   * practically rewritten, due to conflicts wiht bypass iommu feature
>
> CC: drjones@redhat.com
> CC: peter.maydell@linaro.org
> CC: shannon.zhaosl@gmail.com
> CC: qemu-arm@nongnu.org
> CC: wangxingang5@huawei.com
> CC: Eric Auger <eric.auger@redhat.com>
> ---
>  include/hw/acpi/acpi-defs.h |  71 ---------------
>  hw/arm/virt-acpi-build.c    | 167 ++++++++++++++++++++----------------
>  2 files changed, 91 insertions(+), 147 deletions(-)
>
> diff --git a/include/hw/acpi/acpi-defs.h b/include/hw/acpi/acpi-defs.h
> index 195f90caf6..6f2f08a9de 100644
> --- a/include/hw/acpi/acpi-defs.h
> +++ b/include/hw/acpi/acpi-defs.h
> @@ -188,75 +188,4 @@ struct AcpiGenericTimerTable {
>  } QEMU_PACKED;
>  typedef struct AcpiGenericTimerTable AcpiGenericTimerTable;
>  
> -/*
> - * IORT node types
> - */
> -
> -#define ACPI_IORT_NODE_HEADER_DEF   /* Node format common fields */ \
> -    uint8_t  type;          \
> -    uint16_t length;        \
> -    uint8_t  revision;      \
> -    uint32_t reserved;      \
> -    uint32_t mapping_count; \
> -    uint32_t mapping_offset;
> -
> -/* Values for node Type above */
> -enum {
> -        ACPI_IORT_NODE_ITS_GROUP = 0x00,
> -        ACPI_IORT_NODE_NAMED_COMPONENT = 0x01,
> -        ACPI_IORT_NODE_PCI_ROOT_COMPLEX = 0x02,
> -        ACPI_IORT_NODE_SMMU = 0x03,
> -        ACPI_IORT_NODE_SMMU_V3 = 0x04
> -};
> -
> -struct AcpiIortIdMapping {
> -    uint32_t input_base;
> -    uint32_t id_count;
> -    uint32_t output_base;
> -    uint32_t output_reference;
> -    uint32_t flags;
> -} QEMU_PACKED;
> -typedef struct AcpiIortIdMapping AcpiIortIdMapping;
> -
> -struct AcpiIortMemoryAccess {
> -    uint32_t cache_coherency;
> -    uint8_t  hints;
> -    uint16_t reserved;
> -    uint8_t  memory_flags;
> -} QEMU_PACKED;
> -typedef struct AcpiIortMemoryAccess AcpiIortMemoryAccess;
> -
> -struct AcpiIortItsGroup {
> -    ACPI_IORT_NODE_HEADER_DEF
> -    uint32_t its_count;
> -    uint32_t identifiers[];
> -} QEMU_PACKED;
> -typedef struct AcpiIortItsGroup AcpiIortItsGroup;
> -
> -#define ACPI_IORT_SMMU_V3_COHACC_OVERRIDE 1
> -
> -struct AcpiIortSmmu3 {
> -    ACPI_IORT_NODE_HEADER_DEF
> -    uint64_t base_address;
> -    uint32_t flags;
> -    uint32_t reserved2;
> -    uint64_t vatos_address;
> -    uint32_t model;
> -    uint32_t event_gsiv;
> -    uint32_t pri_gsiv;
> -    uint32_t gerr_gsiv;
> -    uint32_t sync_gsiv;
> -    AcpiIortIdMapping id_mapping_array[];
> -} QEMU_PACKED;
> -typedef struct AcpiIortSmmu3 AcpiIortSmmu3;
> -
> -struct AcpiIortRC {
> -    ACPI_IORT_NODE_HEADER_DEF
> -    AcpiIortMemoryAccess memory_properties;
> -    uint32_t ats_attribute;
> -    uint32_t pci_segment_number;
> -    AcpiIortIdMapping id_mapping_array[];
> -} QEMU_PACKED;
> -typedef struct AcpiIortRC AcpiIortRC;
> -
>  #endif
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index bceb1b3b7e..4c682e7b09 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -240,6 +240,28 @@ static void acpi_dsdt_add_tpm(Aml *scope, 
> VirtMachineState *vms)
>  }
>  #endif
>  
> +#define ID_MAPPING_ENTRY_SIZE 20
> +#define SMMU_V3_ENTRY_SIZE 60
> +#define ROOT_COMPLEX_ENTRY_SIZE 32
> +#define IORT_NODE_OFFSET 48
> +
> +static void build_iort_id_mapping(GArray *table_data, uint32_t input_base,
> +                                  uint32_t id_count, uint32_t out_ref)
> +{
> +    /* Identity RID mapping covering the whole input RID range */
> +    build_append_int_noprefix(table_data, input_base, 4); /* Input base */
> +    build_append_int_noprefix(table_data, id_count, 4); /* Number of IDs */
> +    build_append_int_noprefix(table_data, input_base, 4); /* Output base */
> +    build_append_int_noprefix(table_data, out_ref, 4); /* Output Reference */
> +    build_append_int_noprefix(table_data, 0, 4); /* Flags */
> +}
> +
> +struct AcpiIortIdMapping {
> +    uint32_t input_base;
> +    uint32_t id_count;
> +};
> +typedef struct AcpiIortIdMapping AcpiIortIdMapping;
> +
>  /* Build the iort ID mapping to SMMUv3 for a given PCI host bridge */
>  static int
>  iort_host_bridges(Object *obj, void *opaque)
> @@ -281,18 +303,17 @@ static int iort_idmap_compare(gconstpointer a, 
> gconstpointer b)
>  static void
>  build_iort(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>  {
> -    int i, nb_nodes, rc_mapping_count;
> -    AcpiIortIdMapping *idmap;
> -    AcpiIortItsGroup *its;
> -    AcpiIortSmmu3 *smmu;
> -    AcpiIortRC *rc;
> +    int i, rc_mapping_count;
>      const uint32_t iort_node_offset = 48;
can be replaced by IORT_NODE_OFFSET now
>      size_t node_size, smmu_offset = 0;
> +    AcpiIortIdMapping *idmap;
>      GArray *smmu_idmaps = g_array_new(false, true, 
> sizeof(AcpiIortIdMapping));
>      GArray *its_idmaps = g_array_new(false, true, sizeof(AcpiIortIdMapping));
>  
>      AcpiTable table = { .sig = "IORT", .rev = 0, .oem_id = vms->oem_id,
>                          .oem_table_id = vms->oem_table_id };
> +    /* Table 2 The IORT */
> +    acpi_table_begin(&table, table_data);
nit: you could have done this move in previous patch.
>  
>      if (vms->iommu == VIRT_IOMMU_SMMUV3) {
>  
> @@ -325,106 +346,100 @@ build_iort(GArray *table_data, BIOSLinker *linker, 
> VirtMachineState *vms)
>              g_array_append_val(its_idmaps, next_range);
>          }
>  
> -        nb_nodes = 3; /* RC, ITS, SMMUv3 */
>          rc_mapping_count = smmu_idmaps->len + its_idmaps->len;
> +        /* Number of IORT Nodes */
> +        build_append_int_noprefix(table_data, 3 /* RC, ITS, SMMUv3 */, 4);
>      } else {
> -        nb_nodes = 2; /* RC, ITS */
>          rc_mapping_count = 1;
> +        /* Number of IORT Nodes */
> +        build_append_int_noprefix(table_data, 2 /* RC, ITS */, 4);
I think I would prefer to keep the nb_nodes variable and do the
corresponding build_append_int_noprefix only once. There may be
additional nodes added with increased complexity and potential extra
duplication.
>      }
>  
> -    /* Table 2 The IORT */
> -    acpi_table_begin(&table, table_data);
> -    /* Number of IORT Nodes */
> -    build_append_int_noprefix(table_data, nb_nodes, 4);
>      /* Offset to Array of IORT Nodes */
> -    build_append_int_noprefix(table_data, iort_node_offset, 4);
> +    build_append_int_noprefix(table_data, IORT_NODE_OFFSET, 4);
>      build_append_int_noprefix(table_data, 0, 4); /* Reserved */
>  
> -    /* ITS group node */
> -    node_size =  sizeof(*its) + sizeof(uint32_t);
> -    its = acpi_data_push(table_data, node_size);
> -
> -    its->type = ACPI_IORT_NODE_ITS_GROUP;
> -    its->length = cpu_to_le16(node_size);
> -    its->its_count = cpu_to_le32(1);
> -    its->identifiers[0] = 0; /* MADT translation_id */
> +    /* 3.1.1.3 ITS group node */
> +    build_append_int_noprefix(table_data, 0 /* ITS Group */, 1); /* Type */
> +    node_size =  20 /* fixed header size */ + 4 /* 1 GIC ITS Identifier */;
> +    build_append_int_noprefix(table_data, node_size, 2); /* Length */
> +    build_append_int_noprefix(table_data, 0, 1); /* Revision */
> +    build_append_int_noprefix(table_data, 0, 4); /* Reserved */
> +    build_append_int_noprefix(table_data, 0, 4); /* Number of ID mappings */
> +    build_append_int_noprefix(table_data, 0, 4); /* Reference to ID Array */
> +    build_append_int_noprefix(table_data, 1, 4); /* Number of ITSs */
> +    /* GIC ITS Identifier Array */
> +    build_append_int_noprefix(table_data, 0 /* MADT translation_id */, 4);
>  
>      if (vms->iommu == VIRT_IOMMU_SMMUV3) {
>          int irq =  vms->irqmap[VIRT_SMMU] + ARM_SPI_BASE;
>  
> -        /* SMMUv3 node */
> -        smmu_offset = iort_node_offset + node_size;
> -        node_size = sizeof(*smmu) + sizeof(*idmap);
> -        smmu = acpi_data_push(table_data, node_size);
> -
> -        smmu->type = ACPI_IORT_NODE_SMMU_V3;
> -        smmu->length = cpu_to_le16(node_size);
> -        smmu->mapping_count = cpu_to_le32(1);
> -        smmu->mapping_offset = cpu_to_le32(sizeof(*smmu));
> -        smmu->base_address = cpu_to_le64(vms->memmap[VIRT_SMMU].base);
> -        smmu->flags = cpu_to_le32(ACPI_IORT_SMMU_V3_COHACC_OVERRIDE);
> -        smmu->event_gsiv = cpu_to_le32(irq);
> -        smmu->pri_gsiv = cpu_to_le32(irq + 1);
> -        smmu->sync_gsiv = cpu_to_le32(irq + 2);
> -        smmu->gerr_gsiv = cpu_to_le32(irq + 3);
> -
> -        /* Identity RID mapping covering the whole input RID range */
> -        idmap = &smmu->id_mapping_array[0];
> -        idmap->input_base = 0;
> -        idmap->id_count = cpu_to_le32(0xFFFF);
> -        idmap->output_base = 0;
> -        /* output IORT node is the ITS group node (the first node) */
> -        idmap->output_reference = cpu_to_le32(iort_node_offset);
> +        smmu_offset = table_data->len - table.table_offset;
> +        /* 3.1.1.2 SMMUv3 */
> +        build_append_int_noprefix(table_data, 4 /* SMMUv3 */, 1); /* Type */
> +        node_size =  SMMU_V3_ENTRY_SIZE + ID_MAPPING_ENTRY_SIZE;
> +        build_append_int_noprefix(table_data, node_size, 2); /* Length */
> +        build_append_int_noprefix(table_data, 0, 1); /* Revision */
> +        build_append_int_noprefix(table_data, 0, 4); /* Reserved */
> +        build_append_int_noprefix(table_data, 1, 4); /* Number of ID 
> mappings */
> +        /* Reference to ID Array */
> +        build_append_int_noprefix(table_data, SMMU_V3_ENTRY_SIZE, 4);
> +        /* Base address */
> +        build_append_int_noprefix(table_data, vms->memmap[VIRT_SMMU].base, 
> 8);
> +        /* Flags */
> +        build_append_int_noprefix(table_data, 1 /* COHACC OverrideNote */, 
> 4);
> +        build_append_int_noprefix(table_data, 0, 4); /* Reserved */
> +        build_append_int_noprefix(table_data, 0, 8); /* VATOS address */
> +        /* Model */
> +        build_append_int_noprefix(table_data, 0 /* Generic SMMU-v3 */, 4);
> +        build_append_int_noprefix(table_data, irq, 4); /* Event */
> +        build_append_int_noprefix(table_data, irq + 1, 4); /* PRI */
> +        build_append_int_noprefix(table_data, irq + 3, 4); /* GERR */
> +        build_append_int_noprefix(table_data, irq + 2, 4); /* Sync */
Please keep that comment. I think it helps
       /* output IORT node is the ITS group node (the first node) */
> +
> +        build_iort_id_mapping(table_data, 0, 0xFFFF, IORT_NODE_OFFSET);
>      }
>  
> -    /* Root Complex Node */
> -    node_size = sizeof(*rc) + sizeof(*idmap) * rc_mapping_count;
> -    rc = acpi_data_push(table_data, node_size);
> -
> -    rc->type = ACPI_IORT_NODE_PCI_ROOT_COMPLEX;
> -    rc->length = cpu_to_le16(node_size);
> -    rc->mapping_count = cpu_to_le32(rc_mapping_count);
> -    rc->mapping_offset = cpu_to_le32(sizeof(*rc));
> -
> +    /* Table 16 Root Complex Node */
> +    build_append_int_noprefix(table_data, 2 /* Root complex */, 1); /* Type 
> */
> +    node_size =  ROOT_COMPLEX_ENTRY_SIZE +
> +                 ID_MAPPING_ENTRY_SIZE * rc_mapping_count;
> +    build_append_int_noprefix(table_data, node_size, 2); /* Length */
> +    build_append_int_noprefix(table_data, 0, 1); /* Revision */
> +    build_append_int_noprefix(table_data, 0, 4); /* Reserved */
> +    /* Number of ID mappings */
> +    build_append_int_noprefix(table_data, rc_mapping_count, 4);
> +    /* Reference to ID Array */
> +    build_append_int_noprefix(table_data, ROOT_COMPLEX_ENTRY_SIZE, 4);
>      /* fully coherent device */
this comment should become /* Memory access properties */ for homogenity
> -    rc->memory_properties.cache_coherency = cpu_to_le32(1);
> -    rc->memory_properties.memory_flags = 0x3; /* CCA = CPM = DCAS = 1 */
> -    rc->pci_segment_number = 0; /* MCFG pci_segment */
> -
> +    build_append_int_noprefix(table_data,
> +        1 | /* CCA: Cache Coherent Attribute, The device is fully coherent */
> +        (3ULL << 7 * 8) /* MAF: Memory Access Flags, CCA = CPM = DCAS = 1 */,
> +        8);
I think we would gain in readability if we were to split into multiple

build_append_int_noprefix according to Table 13 fields

> +    build_append_int_noprefix(table_data, 0, 4); /* ATS Attribute */
> +    /* MCFG pci_segment */
> +    build_append_int_noprefix(table_data, 0, 4); /* PCI Segment number */
> +
> +    /* Output Reference */
>      if (vms->iommu == VIRT_IOMMU_SMMUV3) {
>          AcpiIortIdMapping *range;
>  
>          /* translated RIDs connect to SMMUv3 node: RC -> SMMUv3 -> ITS */
>          for (i = 0; i < smmu_idmaps->len; i++) {
> -            idmap = &rc->id_mapping_array[i];
>              range = &g_array_index(smmu_idmaps, AcpiIortIdMapping, i);
> -
> -            idmap->input_base = cpu_to_le32(range->input_base);
> -            idmap->id_count = cpu_to_le32(range->id_count);
> -            idmap->output_base = cpu_to_le32(range->input_base);
> -            /* output IORT node is the smmuv3 node */
> -            idmap->output_reference = cpu_to_le32(smmu_offset);
please keep the original comment
> +            build_iort_id_mapping(table_data, range->input_base,
> +                                  range->id_count, smmu_offset);
>          }
>  
>          /* bypassed RIDs connect to ITS group node directly: RC -> ITS */
>          for (i = 0; i < its_idmaps->len; i++) {
> -            idmap = &rc->id_mapping_array[smmu_idmaps->len + i];
>              range = &g_array_index(its_idmaps, AcpiIortIdMapping, i);
> -
> -            idmap->input_base = cpu_to_le32(range->input_base);
> -            idmap->id_count = cpu_to_le32(range->id_count);
> -            idmap->output_base = cpu_to_le32(range->input_base);
> -            /* output IORT node is the ITS group node (the first node) */
> -            idmap->output_reference = cpu_to_le32(iort_node_offset);
same, at least it helps me ;-)
> +            build_iort_id_mapping(table_data, range->input_base,
> +                                  range->id_count, iort_node_offset);
>          }
>      } else {
> -        /* Identity RID mapping covering the whole input RID range */
> -        idmap = &rc->id_mapping_array[0];
> -        idmap->input_base = cpu_to_le32(0);
> -        idmap->id_count = cpu_to_le32(0xFFFF);
> -        idmap->output_base = cpu_to_le32(0);
>          /* output IORT node is the ITS group node (the first node) */
> -        idmap->output_reference = cpu_to_le32(iort_node_offset);
> +        build_iort_id_mapping(table_data, 0, 0xFFFF, IORT_NODE_OFFSET);
>      }
>  
>      acpi_table_end(linker, &table);
Thanks

Eric