Re: [PATCH v3 1/4] acpi: Convert build_tpm2() to build_append* API

[Stefan Berger]

On 6/1/20 5:57 AM, Eric Auger wrote:
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.au...@redhat.com>
---
  hw/i386/acpi-build.c | 28 +++++++++++++++++++---------
  1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index b5669d6c65..f0d35d7b17 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -2298,30 +2298,40 @@ 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));

And now you want to build the data structure by pushing fields? I would 
definitely NOT do this.


      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);