acpi: Convert build_tpm2() to build_append* API

In preparation of its move to the generic acpi code,
let's convert build_tpm2() to use build_append API. This
latter now is prefered in place of direct ACPI struct field
settings with manual endianness conversion.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Message-Id: <20200601095737.32671-2-eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/i386/acpi-build.c

@@ -2197,30 +2197,40 @@ build_tpm_tcpa(GArray *table_data, BIOSLinker *linker, GArray *tcpalog)
 static void
 build_tpm2(GArray *table_data, BIOSLinker *linker, GArray *tcpalog)
 {
-    Acpi20TPM2 *tpm2_ptr = acpi_data_push(table_data, sizeof *tpm2_ptr);
+    Acpi20TPM2 *tpm2_ptr = acpi_data_push(table_data, sizeof(AcpiTableHeader));
     unsigned log_addr_size = sizeof(tpm2_ptr->log_area_start_address);
     unsigned log_addr_offset =
         (char *)&tpm2_ptr->log_area_start_address - table_data->data;
+    uint8_t start_method_params[12] = {};
 
-    tpm2_ptr->platform_class = cpu_to_le16(TPM2_ACPI_CLASS_CLIENT);
+    /* platform class */
+    build_append_int_noprefix(table_data, TPM2_ACPI_CLASS_CLIENT, 2);
+    /* reserved */
+    build_append_int_noprefix(table_data, 0, 2);
     if (TPM_IS_TIS_ISA(tpm_find())) {
-        tpm2_ptr->control_area_address = cpu_to_le64(0);
-        tpm2_ptr->start_method = cpu_to_le32(TPM2_START_METHOD_MMIO);
+        /* address of control area */
+        build_append_int_noprefix(table_data, 0, 8);
+        /* start method */
+        build_append_int_noprefix(table_data, TPM2_START_METHOD_MMIO, 4);
     } else if (TPM_IS_CRB(tpm_find())) {
-        tpm2_ptr->control_area_address = cpu_to_le64(TPM_CRB_ADDR_CTRL);
-        tpm2_ptr->start_method = cpu_to_le32(TPM2_START_METHOD_CRB);
+        build_append_int_noprefix(table_data, TPM_CRB_ADDR_CTRL, 8);
+        build_append_int_noprefix(table_data, TPM2_START_METHOD_CRB, 4);
     } else {
         g_warn_if_reached();
     }
 
-    tpm2_ptr->log_area_minimum_length =
-        cpu_to_le32(TPM_LOG_AREA_MINIMUM_SIZE);
+    /* platform specific parameters */
+    g_array_append_vals(table_data, &start_method_params, 12);
 
-    acpi_data_push(tcpalog, le32_to_cpu(tpm2_ptr->log_area_minimum_length));
+    /* log area minimum length */
+    build_append_int_noprefix(table_data, TPM_LOG_AREA_MINIMUM_SIZE, 4);
+
+    acpi_data_push(tcpalog, TPM_LOG_AREA_MINIMUM_SIZE);
     bios_linker_loader_alloc(linker, ACPI_BUILD_TPMLOG_FILE, tcpalog, 1,
                              false);
 
     /* log area start address to be filled by Guest linker */
+    build_append_int_noprefix(table_data, 0, 8);
     bios_linker_loader_add_pointer(linker, ACPI_BUILD_TABLE_FILE,
                                    log_addr_offset, log_addr_size,
                                    ACPI_BUILD_TPMLOG_FILE, 0);