On 01/16/18 16:51, Stefan Berger wrote:
> To avoid having to hard code the base address of the PPI virtual memory
> device we introduce a QEMU ACPI table that holds the base address, if a
> TPM 1.2 or 2 is used. This table gives us flexibility to move the base
> address later on.
>
> Signed-off-by: Stefan Berger <stef...@linux.vnet.ibm.com>
> ---
> hw/i386/acpi-build.c | 19 +++++++++++++++++++
> include/hw/acpi/acpi-defs.h | 8 ++++++++
> 2 files changed, 27 insertions(+)
I don't understand how the guest OS is supposed to consume the QEMU
table. The AML code in patch #4 does not seem to consume the QEMU table,
for locating the operation region. I'm not saying that it *should*
consume the QEMU table, only that I'm currently not seeing a use for the
QEMU table.
How is the QEMU table useful? What breaks if we drop it?
(Sorry if we've been through this; then I must have lost context.)
Thanks,
Laszlo
>
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index 18b939e..522d6d2 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -2628,6 +2628,20 @@ static bool acpi_get_mcfg(AcpiMcfgInfo *mcfg)
> return true;
> }
>
> +static void build_qemu(GArray *table_data, BIOSLinker *linker,
> + TPMVersion tpm_version)
> +{
> + AcpiTableQemu *qemu = acpi_data_push(table_data, sizeof(*qemu));
> +
> + if (tpm_version != TPM_VERSION_UNSPEC) {
> + qemu->tpmppi_addr = TPM_PPI_ADDR_BASE;
> + qemu->tpm_version = tpm_version;
> + }
> +
> + build_header(linker, table_data,
> + (void *)qemu, "QEMU", sizeof(*qemu), 1, "QEMU", "CONF");
> +}
> +
> static
> void acpi_build(AcpiBuildTables *tables, MachineState *machine)
> {
> @@ -2734,6 +2748,11 @@ void acpi_build(AcpiBuildTables *tables, MachineState
> *machine)
> &pcms->acpi_nvdimm_state, machine->ram_slots);
> }
>
> + if (misc.tpm_version != TPM_VERSION_UNSPEC) {
> + acpi_add_table(table_offsets, tables_blob);
> + build_qemu(tables_blob, tables->linker, misc.tpm_version);
> + }
> +
> /* Add tables supplied by user (if any) */
> for (u = acpi_table_first(); u; u = acpi_table_next(u)) {
> unsigned len = acpi_table_len(u);
> diff --git a/include/hw/acpi/acpi-defs.h b/include/hw/acpi/acpi-defs.h
> index 80c8099..98764c1 100644
> --- a/include/hw/acpi/acpi-defs.h
> +++ b/include/hw/acpi/acpi-defs.h
> @@ -573,6 +573,14 @@ struct Acpi20TPM2 {
> } QEMU_PACKED;
> typedef struct Acpi20TPM2 Acpi20TPM2;
>
> +/* QEMU - Custom QEMU table */
> +struct AcpiTableQemu {
> + ACPI_TABLE_HEADER_DEF
> + uint32_t tpmppi_addr;
> + uint8_t tpm_version; /* 1 = 1.2, 2 = 2 */
> +};
> +typedef struct AcpiTableQemu AcpiTableQemu;
> +
> /* DMAR - DMA Remapping table r2.2 */
> struct AcpiTableDmar {
> ACPI_TABLE_HEADER_DEF
>
