acpi: build TPM Physical Presence interface

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>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

2 files changed, 405 insertions, 0 deletions

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
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);
+}