[Qemu-devel] [PATCH v16 0/6] Add support for TPM Physical Presence interface

[Qemu-devel] [PATCH v16 0/6] Add support for TPM Physical Presence interface

[Marc-André Lureau]

Hi,

The following patches implement the TPM Physical Presence Interface
that allows a user to set a command via ACPI (sysfs entry in Linux)
that, upon the next reboot, the firmware looks for and acts upon by
sending sequences of commands to the TPM.

A dedicated memory region is added to the TPM CRB & TIS devices, at
address/size 0xFED45000/0x400. A new "etc/tpm/config" fw_cfg entry
holds the location for that PPI region and some version details, to
allow for future flexibility.

With the associated edk2/ovmf firmware, the Windows HLK "PPI 1.3" test
now runs successfully.

It is based on previous work from Stefan Berger ("[PATCH v2 0/4]
Implement Physical Presence interface for TPM 1.2 and 2")

The edk2 support is merged upstream.

v16:
- minor comments and stylistic changes
- add r-b & t-b tags

v15:
- fix crash on reset when PPI is disabled

v14:
- rebased, fixing conflicts after compat-props refactoring
- fix build regression from v13 with --disable-tpm

v13:
- removed needless error handling in tpm_ppi_init()
- splitted "add ACPI memory clear interface"
- moved acpi build function in dedicated hw/acpi/tpm.c
- added some function documentation in headers
- various code cleanups suggested by Philippe
- rebased

Marc-André Lureau (3):
  tpm: add a "ppi" boolean property
  acpi: add ACPI memory clear interface
  tpm: clear RAM when "memory overwrite" requested

Stefan Berger (3):
  tpm: allocate/map buffer for TPM Physical Presence interface
  acpi: expose TPM/PPI configuration parameters to firmware via fw_cfg
  acpi: build TPM Physical Presence interface

 hw/tpm/tpm_ppi.h      |  46 +++++
 include/hw/acpi/tpm.h |  21 ++
 hw/acpi/tpm.c         | 459 ++++++++++++++++++++++++++++++++++++++++++
 hw/core/machine.c     |   8 +
 hw/i386/acpi-build.c  |  29 ++-
 hw/tpm/tpm_crb.c      |  13 ++
 hw/tpm/tpm_ppi.c      |  53 +++++
 hw/tpm/tpm_tis.c      |  13 ++
 stubs/tpm.c           |   5 +
 docs/specs/tpm.txt    | 104 ++++++++++
 hw/acpi/Makefile.objs |   1 +
 hw/tpm/Makefile.objs  |   1 +
 hw/tpm/trace-events   |   3 +
 13 files changed, 754 insertions(+), 2 deletions(-)
 create mode 100644 hw/tpm/tpm_ppi.h
 create mode 100644 hw/acpi/tpm.c
 create mode 100644 hw/tpm/tpm_ppi.c

-- 
2.20.1.98.gecbdaf0899

[Qemu-devel] [PATCH v16 1/6] tpm: add a "ppi" boolean property

[Marc-André Lureau]

The following patches implement the TPM Physical Presence Interface,
make use of a new memory region and a fw_cfg entry. Enable PPI by
default with >=4.0 machine type, to avoid migration issues.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
---
 hw/core/machine.c | 8 ++++++++
 hw/tpm/tpm_crb.c  | 3 +++
 hw/tpm/tpm_tis.c  | 3 +++
 3 files changed, 14 insertions(+)

diff --git a/hw/core/machine.c b/hw/core/machine.c
index f8563efb86..92519637cb 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -40,6 +40,14 @@ GlobalProperty hw_compat_3_1[] = {
         .driver   = "memory-backend-memfd",
         .property = "x-use-canonical-path-for-ramblock-id",
         .value    = "true",
+    },{
+        .driver   = "tpm-crb",
+        .property = "ppi",
+        .value    = "false",
+    },{
+        .driver   = "tpm-tis",
+        .property = "ppi",
+        .value    = "false",
     },
 };
 const size_t hw_compat_3_1_len = G_N_ELEMENTS(hw_compat_3_1);
diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
index a92dd50437..d5b0ac5920 100644
--- a/hw/tpm/tpm_crb.c
+++ b/hw/tpm/tpm_crb.c
@@ -41,6 +41,8 @@ typedef struct CRBState {
     MemoryRegion cmdmem;
 
     size_t be_buffer_size;
+
+    bool ppi_enabled;
 } CRBState;
 
 #define CRB(obj) OBJECT_CHECK(CRBState, (obj), TYPE_TPM_CRB)
@@ -221,6 +223,7 @@ static const VMStateDescription vmstate_tpm_crb = {
 
 static Property tpm_crb_properties[] = {
     DEFINE_PROP_TPMBE("tpmdev", CRBState, tpmbe),
+    DEFINE_PROP_BOOL("ppi", CRBState, ppi_enabled, true),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
index 2563d7501f..1698d83cd3 100644
--- a/hw/tpm/tpm_tis.c
+++ b/hw/tpm/tpm_tis.c
@@ -81,6 +81,8 @@ typedef struct TPMState {
     TPMVersion be_tpm_version;
 
     size_t be_buffer_size;
+
+    bool ppi_enabled;
 } TPMState;
 
 #define TPM(obj) OBJECT_CHECK(TPMState, (obj), TYPE_TPM_TIS)
@@ -954,6 +956,7 @@ static const VMStateDescription vmstate_tpm_tis = {
 static Property tpm_tis_properties[] = {
     DEFINE_PROP_UINT32("irq", TPMState, irq_num, TPM_TIS_IRQ),
     DEFINE_PROP_TPMBE("tpmdev", TPMState, be_driver),
+    DEFINE_PROP_BOOL("ppi", TPMState, ppi_enabled, true),
     DEFINE_PROP_END_OF_LIST(),
 };
 
-- 
2.20.1.98.gecbdaf0899

[Qemu-devel] [PATCH v16 2/6] tpm: allocate/map buffer for TPM Physical Presence interface

[Marc-André Lureau]

From: Stefan Berger <stefanb@linux.vnet.ibm.com>

Implement a virtual memory device for the TPM Physical Presence interface.
The memory is located at 0xFED45000 and used by ACPI to send messages to the
firmware (BIOS) and by the firmware to provide parameters for each one of
the supported codes.

This interface should be used by all TPM devices on x86 and can be
added by calling tpm_ppi_init_io().

Note: bios_linker cannot be used to allocate the PPI memory region,
since the reserved memory should stay stable across reboots, and might
be needed before the ACPI tables are installed.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
---
 hw/tpm/tpm_ppi.h      | 36 ++++++++++++++++++++++++++++++++++++
 include/hw/acpi/tpm.h |  6 ++++++
 hw/tpm/tpm_crb.c      |  7 +++++++
 hw/tpm/tpm_ppi.c      | 31 +++++++++++++++++++++++++++++++
 hw/tpm/tpm_tis.c      |  7 +++++++
 hw/tpm/Makefile.objs  |  1 +
 6 files changed, 88 insertions(+)
 create mode 100644 hw/tpm/tpm_ppi.h
 create mode 100644 hw/tpm/tpm_ppi.c

diff --git a/hw/tpm/tpm_ppi.h b/hw/tpm/tpm_ppi.h
new file mode 100644
index 0000000000..c5e555fe2c
--- /dev/null
+++ b/hw/tpm/tpm_ppi.h
@@ -0,0 +1,36 @@
+/*
+ * TPM Physical Presence Interface
+ *
+ * Copyright (C) 2018 IBM Corporation
+ *
+ * Authors:
+ *  Stefan Berger    <stefanb@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+#ifndef TPM_TPM_PPI_H
+#define TPM_TPM_PPI_H
+
+#include "hw/acpi/tpm.h"
+#include "exec/address-spaces.h"
+
+typedef struct TPMPPI {
+    MemoryRegion ram;
+    uint8_t *buf;
+} TPMPPI;
+
+/**
+ * tpm_ppi_init:
+ * @tpmppi: a TPMPPI
+ * @m: the address-space / MemoryRegion to use
+ * @addr: the address of the PPI region
+ * @obj: the owner object
+ *
+ * Register the TPM PPI memory region at @addr on the given address
+ * space for the object @obj.
+ **/
+void tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
+                  hwaddr addr, Object *obj);
+
+#endif /* TPM_TPM_PPI_H */
diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
index 3580ffd50c..b8796df916 100644
--- a/include/hw/acpi/tpm.h
+++ b/include/hw/acpi/tpm.h
@@ -188,4 +188,10 @@ REG32(CRB_DATA_BUFFER, 0x80)
 #define TPM2_START_METHOD_MMIO      6
 #define TPM2_START_METHOD_CRB       7
 
+/*
+ * Physical Presence Interface
+ */
+#define TPM_PPI_ADDR_SIZE           0x400
+#define TPM_PPI_ADDR_BASE           0xFED45000
+
 #endif /* HW_ACPI_TPM_H */
diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
index d5b0ac5920..012ec686d4 100644
--- a/hw/tpm/tpm_crb.c
+++ b/hw/tpm/tpm_crb.c
@@ -29,6 +29,7 @@
 #include "sysemu/reset.h"
 #include "tpm_int.h"
 #include "tpm_util.h"
+#include "tpm_ppi.h"
 #include "trace.h"
 
 typedef struct CRBState {
@@ -43,6 +44,7 @@ typedef struct CRBState {
     size_t be_buffer_size;
 
     bool ppi_enabled;
+    TPMPPI ppi;
 } CRBState;
 
 #define CRB(obj) OBJECT_CHECK(CRBState, (obj), TYPE_TPM_CRB)
@@ -294,6 +296,11 @@ static void tpm_crb_realize(DeviceState *dev, Error **errp)
     memory_region_add_subregion(get_system_memory(),
         TPM_CRB_ADDR_BASE + sizeof(s->regs), &s->cmdmem);
 
+    if (s->ppi_enabled) {
+        tpm_ppi_init(&s->ppi, get_system_memory(),
+                     TPM_PPI_ADDR_BASE, OBJECT(s));
+    }
+
     qemu_register_reset(tpm_crb_reset, dev);
 }
 
diff --git a/hw/tpm/tpm_ppi.c b/hw/tpm/tpm_ppi.c
new file mode 100644
index 0000000000..cf17779c20
--- /dev/null
+++ b/hw/tpm/tpm_ppi.c
@@ -0,0 +1,31 @@
+/*
+ * tpm_ppi.c - TPM Physical Presence Interface
+ *
+ * Copyright (C) 2018 IBM Corporation
+ *
+ * Authors:
+ *  Stefan Berger <stefanb@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+
+#include "qapi/error.h"
+#include "cpu.h"
+#include "sysemu/memory_mapping.h"
+#include "migration/vmstate.h"
+#include "tpm_ppi.h"
+
+void tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
+                  hwaddr addr, Object *obj)
+{
+    tpmppi->buf = g_malloc0(HOST_PAGE_ALIGN(TPM_PPI_ADDR_SIZE));
+    memory_region_init_ram_device_ptr(&tpmppi->ram, obj, "tpm-ppi",
+                                      TPM_PPI_ADDR_SIZE, tpmppi->buf);
+    vmstate_register_ram(&tpmppi->ram, DEVICE(obj));
+
+    memory_region_add_subregion(m, addr, &tpmppi->ram);
+}
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
index 1698d83cd3..02d9d5c911 100644
--- a/hw/tpm/tpm_tis.c
+++ b/hw/tpm/tpm_tis.c
@@ -31,6 +31,7 @@
 #include "sysemu/tpm_backend.h"
 #include "tpm_int.h"
 #include "tpm_util.h"
+#include "tpm_ppi.h"
 #include "trace.h"
 
 #define TPM_TIS_NUM_LOCALITIES      5     /* per spec */
@@ -83,6 +84,7 @@ typedef struct TPMState {
     size_t be_buffer_size;
 
     bool ppi_enabled;
+    TPMPPI ppi;
 } TPMState;
 
 #define TPM(obj) OBJECT_CHECK(TPMState, (obj), TYPE_TPM_TIS)
@@ -983,6 +985,11 @@ static void tpm_tis_realizefn(DeviceState *dev, Error **errp)
 
     memory_region_add_subregion(isa_address_space(ISA_DEVICE(dev)),
                                 TPM_TIS_ADDR_BASE, &s->mmio);
+
+    if (s->ppi_enabled) {
+        tpm_ppi_init(&s->ppi, isa_address_space(ISA_DEVICE(dev)),
+                     TPM_PPI_ADDR_BASE, OBJECT(s));
+    }
 }
 
 static void tpm_tis_initfn(Object *obj)
diff --git a/hw/tpm/Makefile.objs b/hw/tpm/Makefile.objs
index 1dc9f8bf2c..700c878622 100644
--- a/hw/tpm/Makefile.objs
+++ b/hw/tpm/Makefile.objs
@@ -1,4 +1,5 @@
 common-obj-y += tpm_util.o
+obj-y += tpm_ppi.o
 common-obj-$(CONFIG_TPM_TIS) += tpm_tis.o
 common-obj-$(CONFIG_TPM_CRB) += tpm_crb.o
 common-obj-$(CONFIG_TPM_PASSTHROUGH) += tpm_passthrough.o
-- 
2.20.1.98.gecbdaf0899

[Qemu-devel] [PATCH v16 3/6] acpi: expose TPM/PPI configuration parameters to firmware via fw_cfg

[Marc-André Lureau]

From: Stefan Berger <stefanb@linux.vnet.ibm.com>

To avoid having to hard code the base address of the PPI virtual
memory device we introduce a fw_cfg file etc/tpm/config that holds the
base address of the PPI device, the version of the PPI interface and
the version of the attached TPM.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
[ Marc-André: renamed to etc/tpm/config, made it static, document it ]
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
---
 include/hw/acpi/tpm.h |  3 +++
 hw/i386/acpi-build.c  | 19 +++++++++++++++++++
 docs/specs/tpm.txt    | 19 +++++++++++++++++++
 3 files changed, 41 insertions(+)

diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
index b8796df916..a6109a97fc 100644
--- a/include/hw/acpi/tpm.h
+++ b/include/hw/acpi/tpm.h
@@ -194,4 +194,7 @@ REG32(CRB_DATA_BUFFER, 0x80)
 #define TPM_PPI_ADDR_SIZE           0x400
 #define TPM_PPI_ADDR_BASE           0xFED45000
 
+#define TPM_PPI_VERSION_NONE        0
+#define TPM_PPI_VERSION_1_30        1
+
 #endif /* HW_ACPI_TPM_H */
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 14f757fc36..9898247705 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -119,6 +119,12 @@ typedef struct AcpiBuildPciBusHotplugState {
     bool pcihp_bridge_en;
 } AcpiBuildPciBusHotplugState;
 
+typedef struct FwCfgTPMConfig {
+    uint32_t tpmppi_address;
+    uint8_t tpm_version;
+    uint8_t tpmppi_version;
+} QEMU_PACKED FwCfgTPMConfig;
+
 static void init_common_fadt_data(Object *o, AcpiFadtData *data)
 {
     uint32_t io = object_property_get_uint(o, ACPI_PM_PROP_PM_IO_BASE, NULL);
@@ -2847,6 +2853,8 @@ void acpi_setup(void)
     AcpiBuildTables tables;
     AcpiBuildState *build_state;
     Object *vmgenid_dev;
+    TPMIf *tpm;
+    static FwCfgTPMConfig tpm_config;
 
     if (!pcms->fw_cfg) {
         ACPI_BUILD_DPRINTF("No fw cfg. Bailing out.\n");
@@ -2881,6 +2889,17 @@ void acpi_setup(void)
     fw_cfg_add_file(pcms->fw_cfg, ACPI_BUILD_TPMLOG_FILE,
                     tables.tcpalog->data, acpi_data_len(tables.tcpalog));
 
+    tpm = tpm_find();
+    if (tpm && object_property_get_bool(OBJECT(tpm), "ppi", &error_abort)) {
+        tpm_config = (FwCfgTPMConfig) {
+            .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
+            .tpm_version = tpm_get_version(tpm),
+            .tpmppi_version = TPM_PPI_VERSION_NONE
+        };
+        fw_cfg_add_file(pcms->fw_cfg, "etc/tpm/config",
+                        &tpm_config, sizeof tpm_config);
+    }
+
     vmgenid_dev = find_vmgenid_dev();
     if (vmgenid_dev) {
         vmgenid_add_fw_cfg(VMGENID(vmgenid_dev), pcms->fw_cfg,
diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
index 1af82bba86..e4bb094700 100644
--- a/docs/specs/tpm.txt
+++ b/docs/specs/tpm.txt
@@ -34,6 +34,25 @@ The CRB interface makes a memory mapped IO region in the area 0xfed40000 -
 QEMU files related to TPM CRB interface:
  - hw/tpm/tpm_crb.c
 
+= fw_cfg interface =
+
+The bios/firmware may read the "etc/tpm/config" fw_cfg entry for
+configuring the guest appropriately.
+
+The entry of 6 bytes has the following content, in little-endian:
+
+    #define TPM_VERSION_UNSPEC          0
+    #define TPM_VERSION_1_2             1
+    #define TPM_VERSION_2_0             2
+
+    #define TPM_PPI_VERSION_NONE        0
+    #define TPM_PPI_VERSION_1_30        1
+
+    struct FwCfgTPMConfig {
+        uint32_t tpmppi_address;         /* PPI memory location */
+        uint8_t tpm_version;             /* TPM version */
+        uint8_t tpmppi_version;          /* PPI version */
+    };
 
 = ACPI Interface =
 
-- 
2.20.1.98.gecbdaf0899

[Qemu-devel] [PATCH v16 4/6] acpi: build TPM Physical Presence interface

[Marc-André Lureau]

From: Stefan Berger <stefanb@linux.vnet.ibm.com>

The TPM Physical Presence interface consists of an ACPI part, a shared
memory part, and code in the firmware. Users can send messages to the
firmware by writing a code into the shared memory through invoking the
ACPI code. When a reboot happens, the firmware looks for the code and
acts on it by sending sequences of commands to the TPM.

This patch adds the ACPI code. It is similar to the one in EDK2 but doesn't
assume that SMIs are necessary to use. It uses a similar datastructure for
the shared memory as EDK2 does so that EDK2 and SeaBIOS could both make use
of it. I extended the shared memory data structure with an array of 256
bytes, one for each code that could be implemented. The array contains
flags describing the individual codes. This decouples the ACPI implementation
from the firmware implementation.

The underlying TCG specification is accessible from the following page.

https://trustedcomputinggroup.org/tcg-physical-presence-interface-specification/

This patch implements version 1.30.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
[ Marc-André - ACPI code improvements and windows fixes ]
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
---
 include/hw/acpi/tpm.h |  12 ++
 hw/acpi/tpm.c         | 404 ++++++++++++++++++++++++++++++++++++++++++
 hw/i386/acpi-build.c  |  12 +-
 stubs/tpm.c           |   5 +
 docs/specs/tpm.txt    |  83 +++++++++
 hw/acpi/Makefile.objs |   1 +
 6 files changed, 514 insertions(+), 3 deletions(-)
 create mode 100644 hw/acpi/tpm.c

diff --git a/include/hw/acpi/tpm.h b/include/hw/acpi/tpm.h
index a6109a97fc..1a2a57a21f 100644
--- a/include/hw/acpi/tpm.h
+++ b/include/hw/acpi/tpm.h
@@ -18,6 +18,8 @@
 
 #include "qemu/units.h"
 #include "hw/registerfields.h"
+#include "hw/acpi/aml-build.h"
+#include "sysemu/tpm.h"
 
 #define TPM_TIS_ADDR_BASE           0xFED40000
 #define TPM_TIS_ADDR_SIZE           0x5000
@@ -197,4 +199,14 @@ REG32(CRB_DATA_BUFFER, 0x80)
 #define TPM_PPI_VERSION_NONE        0
 #define TPM_PPI_VERSION_1_30        1
 
+/* whether function is blocked by BIOS settings; bits 0, 1, 2 */
+#define TPM_PPI_FUNC_NOT_IMPLEMENTED     (0 << 0)
+#define TPM_PPI_FUNC_BIOS_ONLY           (1 << 0)
+#define TPM_PPI_FUNC_BLOCKED             (2 << 0)
+#define TPM_PPI_FUNC_ALLOWED_USR_REQ     (3 << 0)
+#define TPM_PPI_FUNC_ALLOWED_USR_NOT_REQ (4 << 0)
+#define TPM_PPI_FUNC_MASK                (7 << 0)
+
+void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev);
+
 #endif /* HW_ACPI_TPM_H */
diff --git a/hw/acpi/tpm.c b/hw/acpi/tpm.c
new file mode 100644
index 0000000000..9f205378f2
--- /dev/null
+++ b/hw/acpi/tpm.c
@@ -0,0 +1,404 @@
+/* Support for generating ACPI TPM tables
+ *
+ * Copyright (C) 2018 IBM, Corp.
+ * Copyright (C) 2018 Red Hat Inc
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/acpi/tpm.h"
+
+void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
+{
+    Aml *method, *field, *ifctx, *ifctx2, *ifctx3, *func_mask,
+        *not_implemented, *pak, *tpm2, *tpm3, *pprm, *pprq, *zero, *one;
+
+    if (!object_property_get_bool(OBJECT(tpm), "ppi", &error_abort)) {
+        return;
+    }
+
+    zero = aml_int(0);
+    one = aml_int(1);
+    func_mask = aml_int(TPM_PPI_FUNC_MASK);
+    not_implemented = aml_int(TPM_PPI_FUNC_NOT_IMPLEMENTED);
+
+    /*
+     * TPP2 is for the registers that ACPI code used to pass
+     * the PPI code and parameter (PPRQ, PPRM) to the firmware.
+     */
+    aml_append(dev,
+               aml_operation_region("TPP2", AML_SYSTEM_MEMORY,
+                                    aml_int(TPM_PPI_ADDR_BASE + 0x100),
+                                    0x5A));
+    field = aml_field("TPP2", AML_ANY_ACC, AML_NOLOCK, AML_PRESERVE);
+    aml_append(field, aml_named_field("PPIN", 8));
+    aml_append(field, aml_named_field("PPIP", 32));
+    aml_append(field, aml_named_field("PPRP", 32));
+    aml_append(field, aml_named_field("PPRQ", 32));
+    aml_append(field, aml_named_field("PPRM", 32));
+    aml_append(field, aml_named_field("LPPR", 32));
+    aml_append(dev, field);
+    pprq = aml_name("PPRQ");
+    pprm = aml_name("PPRM");
+
+    /*
+     * DerefOf in Windows is broken with SYSTEM_MEMORY.  Use a dynamic
+     * operation region inside of a method for getting FUNC[op].
+     */
+    method = aml_method("TPFN", 1, AML_SERIALIZED);
+    {
+        Aml *op = aml_arg(0);
+        ifctx = aml_if(aml_lgreater_equal(op, aml_int(0x100)));
+        {
+            aml_append(ifctx, aml_return(zero));
+        }
+        aml_append(method, ifctx);
+
+        aml_append(method,
+            aml_operation_region("TPP1", AML_SYSTEM_MEMORY,
+                aml_add(aml_int(TPM_PPI_ADDR_BASE), op, NULL), 0x1));
+        field = aml_field("TPP1", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE);
+        aml_append(field, aml_named_field("TPPF", 8));
+        aml_append(method, field);
+        aml_append(method, aml_return(aml_name("TPPF")));
+    }
+    aml_append(dev, method);
+
+    /*
+     * Use global TPM2 & TPM3 variables to workaround Windows ACPI bug
+     * when returning packages.
+     */
+    pak = aml_package(2);
+    aml_append(pak, zero);
+    aml_append(pak, zero);
+    aml_append(dev, aml_name_decl("TPM2", pak));
+    tpm2 = aml_name("TPM2");
+
+    pak = aml_package(3);
+    aml_append(pak, zero);
+    aml_append(pak, zero);
+    aml_append(pak, zero);
+    aml_append(dev, aml_name_decl("TPM3", pak));
+    tpm3 = aml_name("TPM3");
+
+    method = aml_method("_DSM", 4, AML_SERIALIZED);
+    {
+        uint8_t zerobyte[1] = { 0 };
+        Aml *function, *arguments, *rev, *op, *op_arg, *op_flags, *uuid;
+
+        uuid = aml_arg(0);
+        rev = aml_arg(1);
+        function = aml_arg(2);
+        arguments = aml_arg(3);
+        op = aml_local(0);
+        op_flags = aml_local(1);
+
+        /* Physical Presence Interface */
+        ifctx = aml_if(
+            aml_equal(uuid,
+                      aml_touuid("3DDDFAA6-361B-4EB4-A424-8D10089D1653")));
+        {
+            /* standard DSM query function */
+            ifctx2 = aml_if(aml_equal(function, zero));
+            {
+                uint8_t byte_list[2] = { 0xff, 0x01 }; /* functions 1-8 */
+
+                aml_append(ifctx2,
+                           aml_return(aml_buffer(sizeof(byte_list),
+                                                 byte_list)));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.1 Get Physical Presence Interface Version
+             *
+             * Arg 2 (Integer): Function Index = 1
+             * Arg 3 (Package): Arguments = Empty Package
+             * Returns: Type: String
+             */
+            ifctx2 = aml_if(aml_equal(function, one));
+            {
+                aml_append(ifctx2, aml_return(aml_string("1.3")));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.3 Submit TPM Operation Request to Pre-OS Environment
+             *
+             * Arg 2 (Integer): Function Index = 2
+             * Arg 3 (Package): Arguments = Package: Type: Integer
+             *                              Operation Value of the Request
+             * Returns: Type: Integer
+             *          0: Success
+             *          1: Operation Value of the Request Not Supported
+             *          2: General Failure
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(2)));
+            {
+                /* get opcode */
+                aml_append(ifctx2,
+                           aml_store(aml_derefof(aml_index(arguments,
+                                                           zero)), op));
+
+                /* get opcode flags */
+                aml_append(ifctx2,
+                           aml_store(aml_call1("TPFN", op), op_flags));
+
+                /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
+                ifctx3 = aml_if(
+                    aml_equal(
+                        aml_and(op_flags, func_mask, NULL),
+                        not_implemented));
+                {
+                    /* 1: Operation Value of the Request Not Supported */
+                    aml_append(ifctx3, aml_return(one));
+                }
+                aml_append(ifctx2, ifctx3);
+
+                aml_append(ifctx2, aml_store(op, pprq));
+                aml_append(ifctx2, aml_store(zero, pprm));
+                /* 0: success */
+                aml_append(ifctx2, aml_return(zero));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.4 Get Pending TPM Operation Requested By the OS
+             *
+             * Arg 2 (Integer): Function Index = 3
+             * Arg 3 (Package): Arguments = Empty Package
+             * Returns: Type: Package of Integers
+             *          Integer 1: Function Return code
+             *                     0: Success
+             *                     1: General Failure
+             *          Integer 2: Pending operation requested by the OS
+             *                     0: None
+             *                    >0: Operation Value of the Pending Request
+             *          Integer 3: Optional argument to pending operation
+             *                     requested by the OS
+             *                     0: None
+             *                    >0: Argument Value of the Pending Request
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(3)));
+            {
+                /*
+                 * Revision ID of 1, no integer parameter beyond
+                 * parameter two are expected
+                 */
+                ifctx3 = aml_if(aml_equal(rev, one));
+                {
+                    /* TPM2[1] = PPRQ */
+                    aml_append(ifctx3,
+                               aml_store(pprq, aml_index(tpm2, one)));
+                    aml_append(ifctx3, aml_return(tpm2));
+                }
+                aml_append(ifctx2, ifctx3);
+
+                /*
+                 * A return value of {0, 23, 1} indicates that
+                 * operation 23 with argument 1 is pending.
+                 */
+                ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
+                {
+                    /* TPM3[1] = PPRQ */
+                    aml_append(ifctx3,
+                               aml_store(pprq, aml_index(tpm3, one)));
+                    /* TPM3[2] = PPRM */
+                    aml_append(ifctx3,
+                               aml_store(pprm, aml_index(tpm3, aml_int(2))));
+                    aml_append(ifctx3, aml_return(tpm3));
+                }
+                aml_append(ifctx2, ifctx3);
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.5 Get Platform-Specific Action to Transition to
+             *     Pre-OS Environment
+             *
+             * Arg 2 (Integer): Function Index = 4
+             * Arg 3 (Package): Arguments = Empty Package
+             * Returns: Type: Integer
+             *          0: None
+             *          1: Shutdown
+             *          2: Reboot
+             *          3: OS Vendor-specific
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(4)));
+            {
+                /* reboot */
+                aml_append(ifctx2, aml_return(aml_int(2)));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.6 Return TPM Operation Response to OS Environment
+             *
+             * Arg 2 (Integer): Function Index = 5
+             * Arg 3 (Package): Arguments = Empty Package
+             * Returns: Type: Package of Integer
+             *          Integer 1: Function Return code
+             *                     0: Success
+             *                     1: General Failure
+             *          Integer 2: Most recent operation request
+             *                     0: None
+             *                    >0: Operation Value of the most recent request
+             *          Integer 3: Response to the most recent operation request
+             *                     0: Success
+             *                     0x00000001..0x00000FFF: Corresponding TPM
+             *                                             error code
+             *                     0xFFFFFFF0: User Abort or timeout of dialog
+             *                     0xFFFFFFF1: firmware Failure
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(5)));
+            {
+                /* TPM3[1] = LPPR */
+                aml_append(ifctx2,
+                           aml_store(aml_name("LPPR"),
+                                     aml_index(tpm3, one)));
+                /* TPM3[2] = PPRP */
+                aml_append(ifctx2,
+                           aml_store(aml_name("PPRP"),
+                                     aml_index(tpm3, aml_int(2))));
+                aml_append(ifctx2, aml_return(tpm3));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.0: 2.1.7 Submit preferred user language
+             *
+             * Arg 2 (Integer): Function Index = 6
+             * Arg 3 (Package): Arguments = String Package
+             *                  Preferred language code
+             * Returns: Type: Integer
+             * Function Return Code
+             *          3: Not implemented
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(6)));
+            {
+                /* 3 = not implemented */
+                aml_append(ifctx2, aml_return(aml_int(3)));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.1: 2.1.7 Submit TPM Operation Request to
+             *     Pre-OS Environment 2
+             *
+             * Arg 2 (Integer): Function Index = 7
+             * Arg 3 (Package): Arguments = Package: Type: Integer
+             *                  Integer 1: Operation Value of the Request
+             *                  Integer 2: Argument for Operation (optional)
+             * Returns: Type: Integer
+             *          0: Success
+             *          1: Not Implemented
+             *          2: General Failure
+             *          3: Operation blocked by current firmware settings
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(7)));
+            {
+                /* get opcode */
+                aml_append(ifctx2, aml_store(aml_derefof(aml_index(arguments,
+                                                                   zero)),
+                                             op));
+
+                /* get opcode flags */
+                aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
+                                             op_flags));
+                /* if func[opcode] & TPM_PPI_FUNC_NOT_IMPLEMENTED */
+                ifctx3 = aml_if(
+                    aml_equal(
+                        aml_and(op_flags, func_mask, NULL),
+                        not_implemented));
+                {
+                    /* 1: not implemented */
+                    aml_append(ifctx3, aml_return(one));
+                }
+                aml_append(ifctx2, ifctx3);
+
+                /* if func[opcode] & TPM_PPI_FUNC_BLOCKED */
+                ifctx3 = aml_if(
+                    aml_equal(
+                        aml_and(op_flags, func_mask, NULL),
+                        aml_int(TPM_PPI_FUNC_BLOCKED)));
+                {
+                    /* 3: blocked by firmware */
+                    aml_append(ifctx3, aml_return(aml_int(3)));
+                }
+                aml_append(ifctx2, ifctx3);
+
+                /* revision to integer */
+                ifctx3 = aml_if(aml_equal(rev, one));
+                {
+                    /* revision 1 */
+                    /* PPRQ = op */
+                    aml_append(ifctx3, aml_store(op, pprq));
+                    /* no argument, PPRM = 0 */
+                    aml_append(ifctx3, aml_store(zero, pprm));
+                }
+                aml_append(ifctx2, ifctx3);
+
+                ifctx3 = aml_if(aml_equal(rev, aml_int(2)));
+                {
+                    /* revision 2 */
+                    /* PPRQ = op */
+                    op_arg = aml_derefof(aml_index(arguments, one));
+                    aml_append(ifctx3, aml_store(op, pprq));
+                    /* PPRM = arg3[1] */
+                    aml_append(ifctx3, aml_store(op_arg, pprm));
+                }
+                aml_append(ifctx2, ifctx3);
+                /* 0: success */
+                aml_append(ifctx2, aml_return(zero));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * PPI 1.1: 2.1.8 Get User Confirmation Status for Operation
+             *
+             * Arg 2 (Integer): Function Index = 8
+             * Arg 3 (Package): Arguments = Package: Type: Integer
+             *                  Operation Value that may need user confirmation
+             * Returns: Type: Integer
+             *          0: Not implemented
+             *          1: Firmware only
+             *          2: Blocked for OS by firmware configuration
+             *          3: Allowed and physically present user required
+             *          4: Allowed and physically present user not required
+             */
+            ifctx2 = aml_if(aml_equal(function, aml_int(8)));
+            {
+                /* get opcode */
+                aml_append(ifctx2,
+                           aml_store(aml_derefof(aml_index(arguments,
+                                                           zero)),
+                                     op));
+
+                /* get opcode flags */
+                aml_append(ifctx2, aml_store(aml_call1("TPFN", op),
+                                             op_flags));
+                /* return confirmation status code */
+                aml_append(ifctx2,
+                           aml_return(
+                               aml_and(op_flags, func_mask, NULL)));
+            }
+            aml_append(ifctx, ifctx2);
+
+            aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
+        }
+        aml_append(method, ifctx);
+    }
+    aml_append(dev, method);
+}
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 9898247705..2e21a31f82 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -1802,6 +1802,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
     uint32_t nr_mem = machine->ram_slots;
     int root_bus_limit = 0xFF;
     PCIBus *bus = NULL;
+    TPMIf *tpm = tpm_find();
     int i;
 
     dsdt = init_aml_allocator();
@@ -2139,7 +2140,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
             /* Scan all PCI buses. Generate tables to support hotplug. */
             build_append_pci_bus_devices(scope, bus, pm->pcihp_bridge_en);
 
-            if (TPM_IS_TIS(tpm_find())) {
+            if (TPM_IS_TIS(tpm)) {
                 dev = aml_device("ISA.TPM");
                 aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0C31")));
                 aml_append(dev, aml_name_decl("_STA", aml_int(0xF)));
@@ -2153,6 +2154,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
                  */
                 /* aml_append(crs, aml_irq_no_flags(TPM_TIS_IRQ)); */
                 aml_append(dev, aml_name_decl("_CRS", crs));
+
+                tpm_build_ppi_acpi(tpm, dev);
+
                 aml_append(scope, dev);
             }
 
@@ -2160,7 +2164,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
         }
     }
 
-    if (TPM_IS_CRB(tpm_find())) {
+    if (TPM_IS_CRB(tpm)) {
         dev = aml_device("TPM");
         aml_append(dev, aml_name_decl("_HID", aml_string("MSFT0101")));
         crs = aml_resource_template();
@@ -2172,6 +2176,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
         aml_append(method, aml_return(aml_int(0x0f)));
         aml_append(dev, method);
 
+        tpm_build_ppi_acpi(tpm, dev);
+
         aml_append(sb_scope, dev);
     }
 
@@ -2894,7 +2900,7 @@ void acpi_setup(void)
         tpm_config = (FwCfgTPMConfig) {
             .tpmppi_address = cpu_to_le32(TPM_PPI_ADDR_BASE),
             .tpm_version = tpm_get_version(tpm),
-            .tpmppi_version = TPM_PPI_VERSION_NONE
+            .tpmppi_version = TPM_PPI_VERSION_1_30
         };
         fw_cfg_add_file(pcms->fw_cfg, "etc/tpm/config",
                         &tpm_config, sizeof tpm_config);
diff --git a/stubs/tpm.c b/stubs/tpm.c
index 80939cd3db..66c99d667d 100644
--- a/stubs/tpm.c
+++ b/stubs/tpm.c
@@ -8,6 +8,7 @@
 #include "qemu/osdep.h"
 #include "qapi/qapi-commands-tpm.h"
 #include "sysemu/tpm.h"
+#include "hw/acpi/tpm.h"
 
 void tpm_init(void)
 {
@@ -31,3 +32,7 @@ TpmModelList *qmp_query_tpm_models(Error **errp)
 {
     return NULL;
 }
+
+void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
+{
+}
diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
index e4bb094700..424d1511fc 100644
--- a/docs/specs/tpm.txt
+++ b/docs/specs/tpm.txt
@@ -76,6 +76,89 @@ URL:
 
 https://trustedcomputinggroup.org/tcg-acpi-specification/
 
+== ACPI PPI Interface ==
+
+QEMU supports the Physical Presence Interface (PPI) for TPM 1.2 and TPM 2. This
+interface requires ACPI and firmware support. The specification can be found at
+the following URL:
+
+https://trustedcomputinggroup.org/resource/tcg-physical-presence-interface-specification/
+
+PPI enables a system administrator (root) to request a modification to the
+TPM upon reboot. The PPI specification defines the operation requests and the
+actions the firmware has to take. The system administrator passes the operation
+request number to the firmware through an ACPI interface which writes this
+number to a memory location that the firmware knows. Upon reboot, the firmware
+finds the number and sends commands to the the TPM. The firmware writes the TPM
+result code and the operation request number to a memory location that ACPI can
+read from and pass the result on to the administrator.
+
+The PPI specification defines a set of mandatory and optional operations for
+the firmware to implement. The ACPI interface also allows an administrator to
+list the supported operations. In QEMU the ACPI code is generated by QEMU, yet
+the firmware needs to implement support on a per-operations basis, and
+different firmwares may support a different subset. Therefore, QEMU introduces
+the virtual memory device for PPI where the firmware can indicate which
+operations it supports and ACPI can enable the ones that are supported and
+disable all others. This interface lies in main memory and has the following
+layout:
+
+ +----------+--------+--------+-------------------------------------------+
+ |  Field   | Length | Offset | Description                               |
+ +----------+--------+--------+-------------------------------------------+
+ | func     |  0x100 |  0x000 | Firmware sets values for each supported   |
+ |          |        |        | operation. See defined values below.      |
+ +----------+--------+--------+-------------------------------------------+
+ | ppin     |   0x1  |  0x100 | SMI interrupt to use. Set by firmware.    |
+ |          |        |        | Not supported.                            |
+ +----------+--------+--------+-------------------------------------------+
+ | ppip     |   0x4  |  0x101 | ACPI function index to pass to SMM code.  |
+ |          |        |        | Set by ACPI. Not supported.               |
+ +----------+--------+--------+-------------------------------------------+
+ | pprp     |   0x4  |  0x105 | Result of last executed operation. Set by |
+ |          |        |        | firmware. See function index 5 for values.|
+ +----------+--------+--------+-------------------------------------------+
+ | pprq     |   0x4  |  0x109 | Operation request number to execute. See  |
+ |          |        |        | 'Physical Presence Interface Operation    |
+ |          |        |        | Summary' tables in specs. Set by ACPI.    |
+ +----------+--------+--------+-------------------------------------------+
+ | pprm     |   0x4  |  0x10d | Operation request optional parameter.     |
+ |          |        |        | Values depend on operation. Set by ACPI.  |
+ +----------+--------+--------+-------------------------------------------+
+ | lppr     |   0x4  |  0x111 | Last executed operation request number.   |
+ |          |        |        | Copied from pprq field by firmware.       |
+ +----------+--------+--------+-------------------------------------------+
+ | fret     |   0x4  |  0x115 | Result code from SMM function.            |
+ |          |        |        | Not supported.                            |
+ +----------+--------+--------+-------------------------------------------+
+ | res1     |  0x40  |  0x119 | Reserved for future use                   |
+ +----------+--------+--------+-------------------------------------------+
+ | next_step|   0x1  |  0x159 | Operation to execute after reboot by      |
+ |          |        |        | firmware. Used by firmware.               |
+ +----------+--------+--------+-------------------------------------------+
+
+   The following values are supported for the 'func' field. They correspond
+   to the values used by ACPI function index 8.
+
+ +----------+-------------------------------------------------------------+
+ | value    | Description                                                 |
+ +----------+-------------------------------------------------------------+
+ | 0        | Operation is not implemented.                               |
+ +----------+-------------------------------------------------------------+
+ | 1        | Operation is only accessible through firmware.              |
+ +----------+-------------------------------------------------------------+
+ | 2        | Operation is blocked for OS by firmware configuration.      |
+ +----------+-------------------------------------------------------------+
+ | 3        | Operation is allowed and physically present user required.  |
+ +----------+-------------------------------------------------------------+
+ | 4        | Operation is allowed and physically present user is not     |
+ |          | required.                                                   |
+ +----------+-------------------------------------------------------------+
+
+The location of the table is given by the fw_cfg tpmppi_address field.
+The PPI memory region size is 0x400 (TPM_PPI_ADDR_SIZE) to leave
+enough room for future updates.
+
 
 QEMU files related to TPM ACPI tables:
  - hw/i386/acpi-build.c
diff --git a/hw/acpi/Makefile.objs b/hw/acpi/Makefile.objs
index 11c35bcb44..2d46e3789a 100644
--- a/hw/acpi/Makefile.objs
+++ b/hw/acpi/Makefile.objs
@@ -11,6 +11,7 @@ common-obj-$(call lnot,$(CONFIG_ACPI_X86)) += acpi-stub.o
 common-obj-y += acpi_interface.o
 common-obj-y += bios-linker-loader.o
 common-obj-y += aml-build.o
+common-obj-$(CONFIG_TPM) += tpm.o
 
 common-obj-$(CONFIG_IPMI) += ipmi.o
 common-obj-$(call lnot,$(CONFIG_IPMI)) += ipmi-stub.o
-- 
2.20.1.98.gecbdaf0899

[Qemu-devel] [PATCH v16 5/6] acpi: add ACPI memory clear interface

[Marc-André Lureau]

The interface is described in the "TCG Platform Reset Attack
Mitigation Specification", chapter 6 "ACPI _DSM Function". According
to Laszlo, it's not so easy to implement in OVMF, he suggested to do
it in qemu instead.

See specification documentation for more details, and next commit for
memory clear on reset handling.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
---
 hw/acpi/tpm.c      | 55 ++++++++++++++++++++++++++++++++++++++++++++++
 docs/specs/tpm.txt |  2 ++
 2 files changed, 57 insertions(+)

diff --git a/hw/acpi/tpm.c b/hw/acpi/tpm.c
index 9f205378f2..b96459e45b 100644
--- a/hw/acpi/tpm.c
+++ b/hw/acpi/tpm.c
@@ -53,6 +53,16 @@ void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
     pprq = aml_name("PPRQ");
     pprm = aml_name("PPRM");
 
+    aml_append(dev,
+               aml_operation_region(
+                   "TPP3", AML_SYSTEM_MEMORY,
+                   aml_int(TPM_PPI_ADDR_BASE +
+                           0x15a /* movv, docs/specs/tpm.txt */),
+                           0x1));
+    field = aml_field("TPP3", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE);
+    aml_append(field, aml_named_field("MOVV", 8));
+    aml_append(dev, field);
+
     /*
      * DerefOf in Windows is broken with SYSTEM_MEMORY.  Use a dynamic
      * operation region inside of a method for getting FUNC[op].
@@ -399,6 +409,51 @@ void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
             aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
         }
         aml_append(method, ifctx);
+
+        /*
+         * "TCG Platform Reset Attack Mitigation Specification 1.00",
+         * Chapter 6 "ACPI _DSM Function"
+         */
+        ifctx = aml_if(
+            aml_equal(uuid,
+                      aml_touuid("376054ED-CC13-4675-901C-4756D7F2D45D")));
+        {
+            /* standard DSM query function */
+            ifctx2 = aml_if(aml_equal(function, zero));
+            {
+                uint8_t byte_list[1] = { 0x03 }; /* functions 1-2 supported */
+
+                aml_append(ifctx2,
+                           aml_return(aml_buffer(sizeof(byte_list),
+                                                 byte_list)));
+            }
+            aml_append(ifctx, ifctx2);
+
+            /*
+             * TCG Platform Reset Attack Mitigation Specification 1.0 Ch.6
+             *
+             * Arg 2 (Integer): Function Index = 1
+             * Arg 3 (Package): Arguments = Package: Type: Integer
+             *                  Operation Value of the Request
+             * Returns: Type: Integer
+             *          0: Success
+             *          1: General Failure
+             */
+            ifctx2 = aml_if(aml_equal(function, one));
+            {
+                aml_append(ifctx2,
+                           aml_store(aml_derefof(aml_index(arguments, zero)),
+                                     op));
+                {
+                    aml_append(ifctx2, aml_store(op, aml_name("MOVV")));
+
+                    /* 0: success */
+                    aml_append(ifctx2, aml_return(zero));
+                }
+            }
+            aml_append(ifctx, ifctx2);
+        }
+        aml_append(method, ifctx);
     }
     aml_append(dev, method);
 }
diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
index 424d1511fc..5d8c26b1ad 100644
--- a/docs/specs/tpm.txt
+++ b/docs/specs/tpm.txt
@@ -135,6 +135,8 @@ layout:
  +----------+--------+--------+-------------------------------------------+
  | next_step|   0x1  |  0x159 | Operation to execute after reboot by      |
  |          |        |        | firmware. Used by firmware.               |
+ +----------+--------+--------+-------------------------------------------+
+ | movv     |   0x1  |  0x15a | Memory overwrite variable                 |
  +----------+--------+--------+-------------------------------------------+
 
    The following values are supported for the 'func' field. They correspond
-- 
2.20.1.98.gecbdaf0899

[Qemu-devel] [PATCH v16 6/6] tpm: clear RAM when "memory overwrite" requested

[Marc-André Lureau]

Note: the "Platform Reset Attack Mitigation" specification isn't
explicit about NVDIMM, since they could have different usages. It uses
the term "system memory" generally (and also "volatile memory RAM" in
its introduction). For initial support, I propose to consider
non-volatile memory as not being subject to the memory clear. There is
an on-going discussion in the TCG "pcclientwg" working group for
future revisions.

CPU cache clearing is done unconditionally in edk2 since commit
d20ae95a13e851 (edk2-stable201811).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
---
 hw/tpm/tpm_ppi.h    | 10 ++++++++++
 hw/tpm/tpm_crb.c    |  3 +++
 hw/tpm/tpm_ppi.c    | 22 ++++++++++++++++++++++
 hw/tpm/tpm_tis.c    |  3 +++
 hw/tpm/trace-events |  3 +++
 5 files changed, 41 insertions(+)

diff --git a/hw/tpm/tpm_ppi.h b/hw/tpm/tpm_ppi.h
index c5e555fe2c..d33ef27de6 100644
--- a/hw/tpm/tpm_ppi.h
+++ b/hw/tpm/tpm_ppi.h
@@ -33,4 +33,14 @@ typedef struct TPMPPI {
 void tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
                   hwaddr addr, Object *obj);
 
+/**
+ * tpm_ppi_reset:
+ * @tpmppi: a TPMPPI
+ *
+ * Function to call on machine reset. It will check if the "Memory
+ * overwrite" variable is set, and perform a memory clear on volatile
+ * memory if requested.
+ **/
+void tpm_ppi_reset(TPMPPI *tpmppi);
+
 #endif /* TPM_TPM_PPI_H */
diff --git a/hw/tpm/tpm_crb.c b/hw/tpm/tpm_crb.c
index 012ec686d4..3087acc4ab 100644
--- a/hw/tpm/tpm_crb.c
+++ b/hw/tpm/tpm_crb.c
@@ -233,6 +233,9 @@ static void tpm_crb_reset(void *dev)
 {
     CRBState *s = CRB(dev);
 
+    if (s->ppi_enabled) {
+        tpm_ppi_reset(&s->ppi);
+    }
     tpm_backend_reset(s->tpmbe);
 
     memset(s->regs, 0, sizeof(s->regs));
diff --git a/hw/tpm/tpm_ppi.c b/hw/tpm/tpm_ppi.c
index cf17779c20..cd8205f212 100644
--- a/hw/tpm/tpm_ppi.c
+++ b/hw/tpm/tpm_ppi.c
@@ -16,8 +16,30 @@
 #include "qapi/error.h"
 #include "cpu.h"
 #include "sysemu/memory_mapping.h"
+#include "sysemu/reset.h"
 #include "migration/vmstate.h"
 #include "tpm_ppi.h"
+#include "trace.h"
+
+void tpm_ppi_reset(TPMPPI *tpmppi)
+{
+    if (tpmppi->buf[0x15a /* movv, docs/specs/tpm.txt */] & 0x1) {
+        GuestPhysBlockList guest_phys_blocks;
+        GuestPhysBlock *block;
+
+        guest_phys_blocks_init(&guest_phys_blocks);
+        guest_phys_blocks_append(&guest_phys_blocks);
+        QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) {
+            trace_tpm_ppi_memset(block->host_addr,
+                                 block->target_end - block->target_start);
+            memset(block->host_addr, 0,
+                   block->target_end - block->target_start);
+            memory_region_set_dirty(block->mr, 0,
+                                    block->target_end - block->target_start);
+        }
+        guest_phys_blocks_free(&guest_phys_blocks);
+    }
+}
 
 void tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
                   hwaddr addr, Object *obj)
diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
index 02d9d5c911..fd6bb9b59a 100644
--- a/hw/tpm/tpm_tis.c
+++ b/hw/tpm/tpm_tis.c
@@ -872,6 +872,9 @@ static void tpm_tis_reset(DeviceState *dev)
     s->be_buffer_size = MIN(tpm_backend_get_buffer_size(s->be_driver),
                             TPM_TIS_BUFFER_MAX);
 
+    if (s->ppi_enabled) {
+        tpm_ppi_reset(&s->ppi);
+    }
     tpm_backend_reset(s->be_driver);
 
     s->active_locty = TPM_TIS_NO_LOCALITY;
diff --git a/hw/tpm/trace-events b/hw/tpm/trace-events
index 25bee0cecf..920d32ad55 100644
--- a/hw/tpm/trace-events
+++ b/hw/tpm/trace-events
@@ -51,3 +51,6 @@ tpm_tis_mmio_write_init_abort(void) "Initiating abort"
 tpm_tis_mmio_write_lowering_irq(void) "Lowering IRQ"
 tpm_tis_mmio_write_data2send(uint32_t value, unsigned size) "Data to send to TPM: 0x%08x (size=%d)"
 tpm_tis_pre_save(uint8_t locty, uint32_t rw_offset) "locty: %d, rw_offset = %u"
+
+# hw/tpm/tpm_ppi.c
+tpm_ppi_memset(uint8_t *ptr, size_t size) "memset: %p %zu"
-- 
2.20.1.98.gecbdaf0899

Re: [Qemu-devel] [PATCH v16 0/6] Add support for TPM Physical Presence interface

[no-reply]

Patchew URL: https://patchew.org/QEMU/20190109193115.20655-1-marcandre.lureau@redhat.com/



Hi,

This series seems to have some coding style problems. See output below for
more information:

Message-id: 20190109193115.20655-1-marcandre.lureau@redhat.com
Type: series
Subject: [Qemu-devel] [PATCH v16 0/6] Add support for TPM Physical Presence interface

=== TEST SCRIPT BEGIN ===
#!/bin/bash
git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram
./scripts/checkpatch.pl --mailback --color=always base..
=== TEST SCRIPT END ===

Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
Switched to a new branch 'test'
16ddac1 tpm: clear RAM when "memory overwrite" requested
bc2cacd acpi: add ACPI memory clear interface
5e862c0 acpi: build TPM Physical Presence interface
e137a73 acpi: expose TPM/PPI configuration parameters to firmware via fw_cfg
c2780c9 tpm: allocate/map buffer for TPM Physical Presence interface
6edda68 tpm: add a "ppi" boolean property

=== OUTPUT BEGIN ===
Unknown option: color
Usage:

    checkpatch.pl [OPTION]... [FILE]...
    checkpatch.pl [OPTION]... [GIT-REV-LIST]

Version: 0.31

Options:
  -q, --quiet                quiet
  --no-tree                  run without a kernel tree
  --no-signoff               do not check for 'Signed-off-by' line
  --patch                    treat FILE as patchfile
  --branch                   treat args as GIT revision list
  --emacs                    emacs compile window format
  --terse                    one line per report
  -f, --file                 treat FILE as regular source file
  --strict                   fail if only warnings are found
  --root=PATH                PATH to the kernel tree root
  --no-summary               suppress the per-file summary
  --mailback                 only produce a report in case of warnings/errors
  --summary-file             include the filename in summary
  --debug KEY=[0|1]          turn on/off debugging of KEY, where KEY is one of
                             'values', 'possible', 'type', and 'attr' (default
                             is all off)
  --test-only=WORD           report only warnings/errors containing WORD
                             literally
  -h, --help, --version      display this help and exit

When FILE is - read standard input.
=== OUTPUT END ===

Test command exited with code: 1


The full log is available at
http://patchew.org/logs/20190109193115.20655-1-marcandre.lureau@redhat.com/testing.checkpatch/?type=message.
---
Email generated automatically by Patchew [http://patchew.org/].
Please send your feedback to patchew-devel@redhat.com

Re: [Qemu-devel] [PATCH v16 5/6] acpi: add ACPI memory clear interface

[Igor Mammedov]

On Wed,  9 Jan 2019 23:31:14 +0400
Marc-André Lureau <marcandre.lureau@redhat.com> wrote:

> The interface is described in the "TCG Platform Reset Attack
> Mitigation Specification", chapter 6 "ACPI _DSM Function". According
I'd add a spec version here as well adn maybe a link like it's
in 4/6 (but links are often go stale so it's not must have, just name
and version should be sufficient to find the spec)

> to Laszlo, it's not so easy to implement in OVMF, he suggested to do
> it in qemu instead.
> 
> See specification documentation for more details, and next commit for
> memory clear on reset handling.
> 
> Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> Tested-by: Stefan Berger <stefanb@linux.ibm.com>
With commit amended 

Reviewed-by: Igor Mammedov <imammedo@redhat.com>

> ---
>  hw/acpi/tpm.c      | 55 ++++++++++++++++++++++++++++++++++++++++++++++
>  docs/specs/tpm.txt |  2 ++
>  2 files changed, 57 insertions(+)
> 
> diff --git a/hw/acpi/tpm.c b/hw/acpi/tpm.c
> index 9f205378f2..b96459e45b 100644
> --- a/hw/acpi/tpm.c
> +++ b/hw/acpi/tpm.c
> @@ -53,6 +53,16 @@ void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
>      pprq = aml_name("PPRQ");
>      pprm = aml_name("PPRM");
>  
> +    aml_append(dev,
> +               aml_operation_region(
> +                   "TPP3", AML_SYSTEM_MEMORY,
> +                   aml_int(TPM_PPI_ADDR_BASE +
> +                           0x15a /* movv, docs/specs/tpm.txt */),
> +                           0x1));
> +    field = aml_field("TPP3", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE);
> +    aml_append(field, aml_named_field("MOVV", 8));
> +    aml_append(dev, field);
> +
>      /*
>       * DerefOf in Windows is broken with SYSTEM_MEMORY.  Use a dynamic
>       * operation region inside of a method for getting FUNC[op].
> @@ -399,6 +409,51 @@ void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
>              aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
>          }
>          aml_append(method, ifctx);
> +
> +        /*
> +         * "TCG Platform Reset Attack Mitigation Specification 1.00",
> +         * Chapter 6 "ACPI _DSM Function"
> +         */
> +        ifctx = aml_if(
> +            aml_equal(uuid,
> +                      aml_touuid("376054ED-CC13-4675-901C-4756D7F2D45D")));
> +        {
> +            /* standard DSM query function */
> +            ifctx2 = aml_if(aml_equal(function, zero));
> +            {
> +                uint8_t byte_list[1] = { 0x03 }; /* functions 1-2 supported */
> +
> +                aml_append(ifctx2,
> +                           aml_return(aml_buffer(sizeof(byte_list),
> +                                                 byte_list)));
> +            }
> +            aml_append(ifctx, ifctx2);
> +
> +            /*
> +             * TCG Platform Reset Attack Mitigation Specification 1.0 Ch.6
> +             *
> +             * Arg 2 (Integer): Function Index = 1
> +             * Arg 3 (Package): Arguments = Package: Type: Integer
> +             *                  Operation Value of the Request
> +             * Returns: Type: Integer
> +             *          0: Success
> +             *          1: General Failure
> +             */
> +            ifctx2 = aml_if(aml_equal(function, one));
> +            {
> +                aml_append(ifctx2,
> +                           aml_store(aml_derefof(aml_index(arguments, zero)),
> +                                     op));
> +                {
> +                    aml_append(ifctx2, aml_store(op, aml_name("MOVV")));
> +
> +                    /* 0: success */
> +                    aml_append(ifctx2, aml_return(zero));
> +                }
> +            }
> +            aml_append(ifctx, ifctx2);
> +        }
> +        aml_append(method, ifctx);
>      }
>      aml_append(dev, method);
>  }
> diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
> index 424d1511fc..5d8c26b1ad 100644
> --- a/docs/specs/tpm.txt
> +++ b/docs/specs/tpm.txt
> @@ -135,6 +135,8 @@ layout:
>   +----------+--------+--------+-------------------------------------------+
>   | next_step|   0x1  |  0x159 | Operation to execute after reboot by      |
>   |          |        |        | firmware. Used by firmware.               |
> + +----------+--------+--------+-------------------------------------------+
> + | movv     |   0x1  |  0x15a | Memory overwrite variable                 |
>   +----------+--------+--------+-------------------------------------------+
>  
>     The following values are supported for the 'func' field. They correspond

Re: [Qemu-devel] [PATCH v16 5/6] acpi: add ACPI memory clear interface

[Marc-André Lureau]

Hi

On Mon, Jan 14, 2019 at 2:17 PM Igor Mammedov <imammedo@redhat.com> wrote:
>
> On Wed,  9 Jan 2019 23:31:14 +0400
> Marc-André Lureau <marcandre.lureau@redhat.com> wrote:
>
> > The interface is described in the "TCG Platform Reset Attack
> > Mitigation Specification", chapter 6 "ACPI _DSM Function". According
> I'd add a spec version here as well adn maybe a link like it's
> in 4/6 (but links are often go stale so it's not must have, just name
> and version should be sufficient to find the spec)
>
> > to Laszlo, it's not so easy to implement in OVMF, he suggested to do
> > it in qemu instead.
> >
> > See specification documentation for more details, and next commit for
> > memory clear on reset handling.
> >
> > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> > Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> > Tested-by: Stefan Berger <stefanb@linux.ibm.com>
> With commit amended
>
> Reviewed-by: Igor Mammedov <imammedo@redhat.com>

Specification Version 1.00
https://www.trustedcomputinggroup.org/wp-content/uploads/Platform-Reset-Attack-Mitigation-Specification.pdf

Michael, do you need me to resend the series or can you update the
commit message?

thanks

>
> > ---
> >  hw/acpi/tpm.c      | 55 ++++++++++++++++++++++++++++++++++++++++++++++
> >  docs/specs/tpm.txt |  2 ++
> >  2 files changed, 57 insertions(+)
> >
> > diff --git a/hw/acpi/tpm.c b/hw/acpi/tpm.c
> > index 9f205378f2..b96459e45b 100644
> > --- a/hw/acpi/tpm.c
> > +++ b/hw/acpi/tpm.c
> > @@ -53,6 +53,16 @@ void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
> >      pprq = aml_name("PPRQ");
> >      pprm = aml_name("PPRM");
> >
> > +    aml_append(dev,
> > +               aml_operation_region(
> > +                   "TPP3", AML_SYSTEM_MEMORY,
> > +                   aml_int(TPM_PPI_ADDR_BASE +
> > +                           0x15a /* movv, docs/specs/tpm.txt */),
> > +                           0x1));
> > +    field = aml_field("TPP3", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE);
> > +    aml_append(field, aml_named_field("MOVV", 8));
> > +    aml_append(dev, field);
> > +
> >      /*
> >       * DerefOf in Windows is broken with SYSTEM_MEMORY.  Use a dynamic
> >       * operation region inside of a method for getting FUNC[op].
> > @@ -399,6 +409,51 @@ void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
> >              aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
> >          }
> >          aml_append(method, ifctx);
> > +
> > +        /*
> > +         * "TCG Platform Reset Attack Mitigation Specification 1.00",
> > +         * Chapter 6 "ACPI _DSM Function"
> > +         */
> > +        ifctx = aml_if(
> > +            aml_equal(uuid,
> > +                      aml_touuid("376054ED-CC13-4675-901C-4756D7F2D45D")));
> > +        {
> > +            /* standard DSM query function */
> > +            ifctx2 = aml_if(aml_equal(function, zero));
> > +            {
> > +                uint8_t byte_list[1] = { 0x03 }; /* functions 1-2 supported */
> > +
> > +                aml_append(ifctx2,
> > +                           aml_return(aml_buffer(sizeof(byte_list),
> > +                                                 byte_list)));
> > +            }
> > +            aml_append(ifctx, ifctx2);
> > +
> > +            /*
> > +             * TCG Platform Reset Attack Mitigation Specification 1.0 Ch.6
> > +             *
> > +             * Arg 2 (Integer): Function Index = 1
> > +             * Arg 3 (Package): Arguments = Package: Type: Integer
> > +             *                  Operation Value of the Request
> > +             * Returns: Type: Integer
> > +             *          0: Success
> > +             *          1: General Failure
> > +             */
> > +            ifctx2 = aml_if(aml_equal(function, one));
> > +            {
> > +                aml_append(ifctx2,
> > +                           aml_store(aml_derefof(aml_index(arguments, zero)),
> > +                                     op));
> > +                {
> > +                    aml_append(ifctx2, aml_store(op, aml_name("MOVV")));
> > +
> > +                    /* 0: success */
> > +                    aml_append(ifctx2, aml_return(zero));
> > +                }
> > +            }
> > +            aml_append(ifctx, ifctx2);
> > +        }
> > +        aml_append(method, ifctx);
> >      }
> >      aml_append(dev, method);
> >  }
> > diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
> > index 424d1511fc..5d8c26b1ad 100644
> > --- a/docs/specs/tpm.txt
> > +++ b/docs/specs/tpm.txt
> > @@ -135,6 +135,8 @@ layout:
> >   +----------+--------+--------+-------------------------------------------+
> >   | next_step|   0x1  |  0x159 | Operation to execute after reboot by      |
> >   |          |        |        | firmware. Used by firmware.               |
> > + +----------+--------+--------+-------------------------------------------+
> > + | movv     |   0x1  |  0x15a | Memory overwrite variable                 |
> >   +----------+--------+--------+-------------------------------------------+
> >
> >     The following values are supported for the 'func' field. They correspond
>

Re: [Qemu-devel] [PATCH v16 5/6] acpi: add ACPI memory clear interface

[Michael S. Tsirkin]

On Mon, Jan 14, 2019 at 02:23:16PM +0400, Marc-André Lureau wrote:
> Hi
> 
> On Mon, Jan 14, 2019 at 2:17 PM Igor Mammedov <imammedo@redhat.com> wrote:
> >
> > On Wed,  9 Jan 2019 23:31:14 +0400
> > Marc-André Lureau <marcandre.lureau@redhat.com> wrote:
> >
> > > The interface is described in the "TCG Platform Reset Attack
> > > Mitigation Specification", chapter 6 "ACPI _DSM Function". According
> > I'd add a spec version here as well adn maybe a link like it's
> > in 4/6 (but links are often go stale so it's not must have, just name
> > and version should be sufficient to find the spec)
> >
> > > to Laszlo, it's not so easy to implement in OVMF, he suggested to do
> > > it in qemu instead.
> > >
> > > See specification documentation for more details, and next commit for
> > > memory clear on reset handling.
> > >
> > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> > > Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> > > Tested-by: Stefan Berger <stefanb@linux.ibm.com>
> > With commit amended
> >
> > Reviewed-by: Igor Mammedov <imammedo@redhat.com>
> 
> Specification Version 1.00
> https://www.trustedcomputinggroup.org/wp-content/uploads/Platform-Reset-Attack-Mitigation-Specification.pdf
> 
> Michael, do you need me to resend the series or can you update the
> commit message?
> 
> thanks

Pls resend in a ready form.
Thanks!

> >
> > > ---
> > >  hw/acpi/tpm.c      | 55 ++++++++++++++++++++++++++++++++++++++++++++++
> > >  docs/specs/tpm.txt |  2 ++
> > >  2 files changed, 57 insertions(+)
> > >
> > > diff --git a/hw/acpi/tpm.c b/hw/acpi/tpm.c
> > > index 9f205378f2..b96459e45b 100644
> > > --- a/hw/acpi/tpm.c
> > > +++ b/hw/acpi/tpm.c
> > > @@ -53,6 +53,16 @@ void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
> > >      pprq = aml_name("PPRQ");
> > >      pprm = aml_name("PPRM");
> > >
> > > +    aml_append(dev,
> > > +               aml_operation_region(
> > > +                   "TPP3", AML_SYSTEM_MEMORY,
> > > +                   aml_int(TPM_PPI_ADDR_BASE +
> > > +                           0x15a /* movv, docs/specs/tpm.txt */),
> > > +                           0x1));
> > > +    field = aml_field("TPP3", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE);
> > > +    aml_append(field, aml_named_field("MOVV", 8));
> > > +    aml_append(dev, field);
> > > +
> > >      /*
> > >       * DerefOf in Windows is broken with SYSTEM_MEMORY.  Use a dynamic
> > >       * operation region inside of a method for getting FUNC[op].
> > > @@ -399,6 +409,51 @@ void tpm_build_ppi_acpi(TPMIf *tpm, Aml *dev)
> > >              aml_append(ifctx, aml_return(aml_buffer(1, zerobyte)));
> > >          }
> > >          aml_append(method, ifctx);
> > > +
> > > +        /*
> > > +         * "TCG Platform Reset Attack Mitigation Specification 1.00",
> > > +         * Chapter 6 "ACPI _DSM Function"
> > > +         */
> > > +        ifctx = aml_if(
> > > +            aml_equal(uuid,
> > > +                      aml_touuid("376054ED-CC13-4675-901C-4756D7F2D45D")));
> > > +        {
> > > +            /* standard DSM query function */
> > > +            ifctx2 = aml_if(aml_equal(function, zero));
> > > +            {
> > > +                uint8_t byte_list[1] = { 0x03 }; /* functions 1-2 supported */
> > > +
> > > +                aml_append(ifctx2,
> > > +                           aml_return(aml_buffer(sizeof(byte_list),
> > > +                                                 byte_list)));
> > > +            }
> > > +            aml_append(ifctx, ifctx2);
> > > +
> > > +            /*
> > > +             * TCG Platform Reset Attack Mitigation Specification 1.0 Ch.6
> > > +             *
> > > +             * Arg 2 (Integer): Function Index = 1
> > > +             * Arg 3 (Package): Arguments = Package: Type: Integer
> > > +             *                  Operation Value of the Request
> > > +             * Returns: Type: Integer
> > > +             *          0: Success
> > > +             *          1: General Failure
> > > +             */
> > > +            ifctx2 = aml_if(aml_equal(function, one));
> > > +            {
> > > +                aml_append(ifctx2,
> > > +                           aml_store(aml_derefof(aml_index(arguments, zero)),
> > > +                                     op));
> > > +                {
> > > +                    aml_append(ifctx2, aml_store(op, aml_name("MOVV")));
> > > +
> > > +                    /* 0: success */
> > > +                    aml_append(ifctx2, aml_return(zero));
> > > +                }
> > > +            }
> > > +            aml_append(ifctx, ifctx2);
> > > +        }
> > > +        aml_append(method, ifctx);
> > >      }
> > >      aml_append(dev, method);
> > >  }
> > > diff --git a/docs/specs/tpm.txt b/docs/specs/tpm.txt
> > > index 424d1511fc..5d8c26b1ad 100644
> > > --- a/docs/specs/tpm.txt
> > > +++ b/docs/specs/tpm.txt
> > > @@ -135,6 +135,8 @@ layout:
> > >   +----------+--------+--------+-------------------------------------------+
> > >   | next_step|   0x1  |  0x159 | Operation to execute after reboot by      |
> > >   |          |        |        | firmware. Used by firmware.               |
> > > + +----------+--------+--------+-------------------------------------------+
> > > + | movv     |   0x1  |  0x15a | Memory overwrite variable                 |
> > >   +----------+--------+--------+-------------------------------------------+
> > >
> > >     The following values are supported for the 'func' field. They correspond
> >