[Qemu-devel] [PATCH FYI 08/13] hw/i386: build UEFI ACPI Data Table for VMGENID in the dedicated blob (WIP)

[Laszlo Ersek <lersek@redhat.com>]

Using the tools
- acpi_add_table2(),
- build_header2()

and the blob
- ACPI_BUILD_QEMUPARAM_FILE

that have been added in the previous patches, we can now implement the
UEFI ACPI Data Table (and the related linker/loader commands) that are
specified in "docs/vmgenid.txt".

At this point the UEFI ACPI Data Table becomes visible to the guest, but
it is never used, because we don't reference it yet from the AML in the
SSDT.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gal Hammer <ghammer@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
---
 hw/i386/acpi-build.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 69 insertions(+)

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 045015e..a742f25 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -41,6 +41,7 @@
 #include "hw/acpi/memory_hotplug.h"
 #include "sysemu/tpm.h"
 #include "hw/acpi/tpm.h"
+#include "hw/acpi/vmgenid.h"
 #include "sysemu/tpm_backend.h"
 
 /* Supported chipsets: */
@@ -1658,6 +1659,69 @@ static bool acpi_has_iommu(void)
     return intel_iommu && !ambiguous;
 }
 
+static void
+build_qemuparam(GArray *qemuparam_blob, GArray *linker)
+{
+    AcpiQemuParamTable *param_table;
+    static const uint8_t ident[ACPI_UEFI_IDENT_SIZE] = QEMU_PARAM_TABLE_GUID;
+
+    /*
+     * The generation ID field -- which lives outside of AcpiQemuParamTable --
+     * must fit in the 4KB blob.
+     */
+    QEMU_BUILD_BUG_ON(VM_GENERATION_ID_OFFSET + VM_GENERATION_ID_SIZE > 4096);
+
+    param_table = acpi_data_push(qemuparam_blob, 4096);
+
+    /* set up the UEFI ACPI Data Table Sub-Header */
+    memcpy(param_table->identifier, ident, ACPI_UEFI_IDENT_SIZE);
+    param_table->data_offset =
+        cpu_to_le16(offsetof(AcpiQemuParamTable, data_offset) +
+                    sizeof param_table->data_offset);
+
+    /* set up the QEMU parameters */
+    param_table->vmgenid_addr_base_ptr = cpu_to_le64(sizeof *param_table);
+
+    /* Prepare linker/loader commands. We handle the allocation of the blob and
+     * the relocation of the "ADDR base pointer" field here. The linking into
+     * the RSDT has already been queued by acpi_add_table2(), whereas
+     * @param_table will be checksummed by build_header2() internally.
+     */
+    bios_linker_loader_alloc(linker,
+                             ACPI_BUILD_QEMUPARAM_FILE,
+                             4096, /* alloc_align */
+                             false /* ie. it can be in high memory */);
+
+    bios_linker_loader_add_pointer(linker,
+                                   /* name of blob containing pointer */
+                                   ACPI_BUILD_QEMUPARAM_FILE,
+                                   /* name of blob being pointed to */
+                                   ACPI_BUILD_QEMUPARAM_FILE,
+                                   /* blob containing pointer */
+                                   qemuparam_blob,
+                                   /* address of pointer */
+                                   &param_table->vmgenid_addr_base_ptr,
+                                   /* size of pointer */
+                                   sizeof param_table->vmgenid_addr_base_ptr);
+
+    build_header2(/* @linker receives the ADD_CHECKSUM command */
+                  linker,
+                  /* the blob in which the ACPI table is embedded */
+                  qemuparam_blob,
+                  /* fw_cfg name of the same */
+                  ACPI_BUILD_QEMUPARAM_FILE,
+                  /* SDT header of ACPI table, residing in the blob */
+                  (AcpiTableHeader *)param_table,
+                  /* ACPI Signature */
+                  "UEFI",
+                  /* ACPI OEM Table ID */
+                  "QEMUPARM",
+                  /* size of ACPI table */
+                  sizeof *param_table,
+                  /* ACPI table revision */
+                  1);
+}
+
 static
 void acpi_build(PcGuestInfo *guest_info, AcpiBuildTables *tables)
 {
@@ -1741,6 +1805,11 @@ void acpi_build(PcGuestInfo *guest_info, AcpiBuildTables *tables)
         acpi_add_table(table_offsets, tables_blob);
         build_dmar_q35(tables_blob, tables->linker);
     }
+    if (true /* lersek: misc.vmgenid_iobase */) {
+        acpi_add_table2(table_offsets, tables->qemuparam_blob,
+                        ACPI_BUILD_QEMUPARAM_FILE);
+        build_qemuparam(tables->qemuparam_blob, tables->linker);
+    }
 
     /* Add tables supplied by user (if any) */
     for (u = acpi_table_first(); u; u = acpi_table_next(u)) {
-- 
1.8.3.1