xref: /openbmc/qemu/hw/tpm/tpm_ppi.c (revision 88cd34ee)
1 /*
2  * tpm_ppi.c - TPM Physical Presence Interface
3  *
4  * Copyright (C) 2018 IBM Corporation
5  *
6  * Authors:
7  *  Stefan Berger <stefanb@us.ibm.com>
8  *
9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
10  * See the COPYING file in the top-level directory.
11  *
12  */
13 
14 #include "qemu/osdep.h"
15 
16 #include "qapi/error.h"
17 #include "cpu.h"
18 #include "sysemu/memory_mapping.h"
19 #include "migration/vmstate.h"
20 #include "tpm_ppi.h"
21 #include "trace.h"
22 
23 void tpm_ppi_reset(TPMPPI *tpmppi)
24 {
25     if (tpmppi->buf[0x15a /* movv, docs/specs/tpm.txt */] & 0x1) {
26         GuestPhysBlockList guest_phys_blocks;
27         GuestPhysBlock *block;
28 
29         guest_phys_blocks_init(&guest_phys_blocks);
30         guest_phys_blocks_append(&guest_phys_blocks);
31         QTAILQ_FOREACH(block, &guest_phys_blocks.head, next) {
32             trace_tpm_ppi_memset(block->host_addr,
33                                  block->target_end - block->target_start);
34             memset(block->host_addr, 0,
35                    block->target_end - block->target_start);
36             memory_region_set_dirty(block->mr, 0,
37                                     block->target_end - block->target_start);
38         }
39         guest_phys_blocks_free(&guest_phys_blocks);
40     }
41 }
42 
43 void tpm_ppi_init(TPMPPI *tpmppi, struct MemoryRegion *m,
44                   hwaddr addr, Object *obj)
45 {
46     tpmppi->buf = qemu_memalign(qemu_real_host_page_size,
47                                 HOST_PAGE_ALIGN(TPM_PPI_ADDR_SIZE));
48     memory_region_init_ram_device_ptr(&tpmppi->ram, obj, "tpm-ppi",
49                                       TPM_PPI_ADDR_SIZE, tpmppi->buf);
50     vmstate_register_ram(&tpmppi->ram, DEVICE(obj));
51 
52     memory_region_add_subregion(m, addr, &tpmppi->ram);
53 }
54