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From: Eric Auger <eric.auger@redhat.com>
To: Igor Mammedov <imammedo@redhat.com>, qemu-devel@nongnu.org
Cc: peter.maydell@linaro.org, drjones@redhat.com,
	wangxingang5@huawei.com, mst@redhat.com,
	shannon.zhaosl@gmail.com, qemu-arm@nongnu.org, ani@anisinha.ca
Subject: Re: [PATCH v4 29/35] acpi: arm/virt: convert build_iort() to endian agnostic build_append_FOO() API
Date: Mon, 27 Sep 2021 11:56:21 +0200	[thread overview]
Message-ID: <a33a9f79-96ef-2d55-90e4-1d015527fd21@redhat.com> (raw)
In-Reply-To: <20210924122802.1455362-30-imammedo@redhat.com>



On 9/24/21 2:27 PM, Igor Mammedov wrote:
> Drop usage of packed structures and explicit endian conversions
> when building IORT table use endian agnostic build_append_int_noprefix()
> API to build it.
>
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> ---
> CC: Eric Auger <eric.auger@redhat.com>
>
> v4:
>   - (Eric Auger <eric.auger@redhat.com>)
>     * keep nb_nodes
>     * encode 'Memory access properties' as separate entries according to
>       Table 13
>     * keep some comments
> 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    | 164 ++++++++++++++++++++----------------
>  2 files changed, 93 insertions(+), 142 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 42ea460313..8c382915a9 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)
> @@ -282,17 +304,16 @@ 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;
> -    const uint32_t iort_node_offset = 48;
> +    const uint32_t iort_node_offset = IORT_NODE_OFFSET;
>      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);
>  
>      if (vms->iommu == VIRT_IOMMU_SMMUV3) {
>          AcpiIortIdMapping next_range = {0};
> @@ -330,100 +351,101 @@ build_iort(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>          nb_nodes = 2; /* RC, ITS */
>          rc_mapping_count = 1;
>      }
> -
> -    /* 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;
> +        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 */
> +
>          /* 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);
>      }
>  
> -    /* 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));
> -
> -    /* fully coherent device */
> -    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 */
> -
> +    /* 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);
> +
> +    /* Table 13 Memory access properties */
> +    /* CCA: Cache Coherent Attribute */
> +    build_append_int_noprefix(table_data, 1 /* fully coherent */, 4);
> +    build_append_int_noprefix(table_data, 0, 1); /* AH: Note Allocation Hints */
> +    build_append_int_noprefix(table_data, 0, 2); /* Reserved */
> +    /* MAF: Note Memory Access Flags */
> +    build_append_int_noprefix(table_data, 0x3 /* CCA = CPM = DCAS = 1 */, 1);
This is DACS and not DCAS but that's not your fault.

we can send a separate trivial patch afterwards to fix the typo.

Sanity checking with GICv3 and GICv2 and SMMUv3.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>

Thank you for the huge refactoring effort

Eric

> +
> +    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);
> +            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);
> +            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);



  reply	other threads:[~2021-09-27 10:11 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-24 12:27 [PATCH v4 00/35] acpi: refactor error prone build_header() and packed structures usage in ACPI tables Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 01/35] acpi: add helper routines to initialize " Igor Mammedov
2021-09-24 20:52   ` Stefan Berger
2021-09-26  9:16   ` wangyanan (Y)
2021-09-24 12:27 ` [PATCH v4 02/35] acpi: build_rsdt: use acpi_table_begin()/acpi_table_end() instead of build_header() Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 03/35] acpi: build_xsdt: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 04/35] acpi: build_slit: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 05/35] acpi: build_fadt: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 06/35] acpi: build_tpm2: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 07/35] acpi: acpi_build_hest: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 08/35] acpi: build_mcfg: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 09/35] acpi: build_hmat: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 10/35] acpi: nvdimm_build_nfit: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 11/35] acpi: nvdimm_build_ssdt: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 12/35] acpi: vmgenid_build_acpi: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 13/35] acpi: x86: build_dsdt: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 14/35] acpi: build_hpet: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 15/35] acpi: build_tpm_tcpa: " Igor Mammedov
2021-09-24 20:46   ` Stefan Berger
2021-09-24 12:27 ` [PATCH v4 16/35] acpi: arm/x86: build_srat: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 17/35] acpi: use build_append_int_noprefix() API to compose SRAT table Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 18/35] acpi: build_dmar_q35: use acpi_table_begin()/acpi_table_end() instead of build_header() Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 19/35] acpi: build_waet: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 20/35] acpi: build_amd_iommu: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 21/35] acpi: madt: arm/x86: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 22/35] acpi: x86: remove dead code Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 23/35] acpi: x86: set enabled when composing _MAT entries Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 24/35] acpi: x86: madt: use build_append_int_noprefix() API to compose MADT table Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 25/35] acpi: arm/virt: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 26/35] acpi: build_dsdt_microvm: use acpi_table_begin()/acpi_table_end() instead of build_header() Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 27/35] acpi: arm: virt: build_dsdt: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 28/35] acpi: arm: virt: build_iort: " Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 29/35] acpi: arm/virt: convert build_iort() to endian agnostic build_append_FOO() API Igor Mammedov
2021-09-27  9:56   ` Eric Auger [this message]
2021-09-24 12:27 ` [PATCH v4 30/35] acpi: arm/virt: build_spcr: fix invalid cast Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 31/35] acpi: arm/virt: build_spcr: use acpi_table_begin()/acpi_table_end() instead of build_header() Igor Mammedov
2021-09-24 12:27 ` [PATCH v4 32/35] acpi: arm/virt: build_gtdt: " Igor Mammedov
2021-09-24 12:28 ` [PATCH v4 33/35] acpi: build_facs: use build_append_int_noprefix() API to compose table Igor Mammedov
2021-09-24 12:28 ` [PATCH v4 34/35] acpi: remove no longer used build_header() Igor Mammedov
2021-09-24 12:28 ` [PATCH v4 35/35] acpi: AcpiGenericAddress no longer used to map/access fields of MMIO, drop packed attribute Igor Mammedov
  -- strict thread matches above, loose matches on Subject: below --
2021-09-22 15:31 [PATCH v3 29/35] acpi: arm/virt: convert build_iort() to endian agnostic build_append_FOO() API Eric Auger
2021-09-23  7:47 ` [PATCH v4 " Igor Mammedov

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