Re: [PATCH v2 1/3] acpi: Move build_tpm2() in the generic part

[Auger Eric <eric.auger@redhat.com>]

Hi,

On 5/6/20 8:33 AM, Andrew Jones wrote:
> On Tue, May 05, 2020 at 04:44:17PM +0200, Eric Auger wrote:
>> We plan to build the tpm2 table on ARM too. In order to reuse the
>> generation code, let's move build_tpm2() to aml-build.c.
>>
>> No change in the implementation.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>> ---
>>  include/hw/acpi/aml-build.h |  2 ++
>>  hw/acpi/aml-build.c         | 30 ++++++++++++++++++++++++++++++
>>  hw/i386/acpi-build.c        | 30 ------------------------------
>>  3 files changed, 32 insertions(+), 30 deletions(-)
>>
>> diff --git a/include/hw/acpi/aml-build.h b/include/hw/acpi/aml-build.h
>> index 0f4ed53d7f..a67ab4618a 100644
>> --- a/include/hw/acpi/aml-build.h
>> +++ b/include/hw/acpi/aml-build.h
>> @@ -437,4 +437,6 @@ void build_slit(GArray *table_data, BIOSLinker *linker, MachineState *ms);
>>  
>>  void build_fadt(GArray *tbl, BIOSLinker *linker, const AcpiFadtData *f,
>>                  const char *oem_id, const char *oem_table_id);
>> +
>> +void build_tpm2(GArray *table_data, BIOSLinker *linker, GArray *tcpalog);
>>  #endif
>> diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
>> index 2c3702b882..1f7fd09112 100644
>> --- a/hw/acpi/aml-build.c
>> +++ b/hw/acpi/aml-build.c
>> @@ -26,6 +26,7 @@
>>  #include "qemu/bitops.h"
>>  #include "sysemu/numa.h"
>>  #include "hw/boards.h"
>> +#include "hw/acpi/tpm.h"
>>  
>>  static GArray *build_alloc_array(void)
>>  {
>> @@ -1875,6 +1876,35 @@ build_hdr:
>>                   "FACP", tbl->len - fadt_start, f->rev, oem_id, oem_table_id);
>>  }
>>  
>> +void build_tpm2(GArray *table_data, BIOSLinker *linker, GArray *tcpalog)
>> +{
>> +    Acpi20TPM2 *tpm2_ptr = acpi_data_push(table_data, sizeof *tpm2_ptr);
>> +    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;
>> +
>> +    tpm2_ptr->platform_class = cpu_to_le16(TPM2_ACPI_CLASS_CLIENT);
>> +    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);
>> +    } 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);
>> +    } else {
>> +        g_warn_if_reached();
>> +    }
>> +
>> +    tpm2_ptr->log_area_minimum_length =
>> +        cpu_to_le32(TPM_LOG_AREA_MINIMUM_SIZE);
>> +
>> +    /* log area start address to be filled by Guest linker */
>> +    bios_linker_loader_add_pointer(linker, ACPI_BUILD_TABLE_FILE,
>> +                                   log_addr_offset, log_addr_size,
>> +                                   ACPI_BUILD_TPMLOG_FILE, 0);
>> +    build_header(linker, table_data,
>> +                 (void *)tpm2_ptr, "TPM2", sizeof(*tpm2_ptr), 4, NULL, NULL);
>> +}
>> +
> 
> I'll let Igor and mst confirm/deny this, but my understanding was that the
> build_append* API was the preferred way to create the table. Indeed, I
> don't see too many table.field = cpu_to_le(...) lines in aml-build.c
> 
> I realize this function is just getting moved, but maybe it should get
> converted to the build_append* API while being moved?

The reason I did not convert is that the struct is as follows

struct Acpi20TPM2 {
    ACPI_TABLE_HEADER_DEF
    uint16_t platform_class;
    uint16_t reserved;
    uint64_t control_area_address;
    uint32_t start_method;
    uint8_t start_method_params[12];
    uint32_t log_area_minimum_length;
    uint64_t log_area_start_address;
} QEMU_PACKED;


If I understand correctly the build_append* adds the fields
contiguously. It was not straightforward to me how to skip the
start_method_params array.

While we are at it the tcpalog arg is not used. Shall I remove it?

Thanks

Eric

> 
> Thanks,
> drew
> 
>