xref: /openbmc/qemu/include/hw/misc/tz-msc.h (revision c418f935)
1 /*
2  * ARM TrustZone master security controller emulation
3  *
4  * Copyright (c) 2018 Linaro Limited
5  * Written by Peter Maydell
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 or
9  * (at your option) any later version.
10  */
11 
12 /*
13  * This is a model of the TrustZone master security controller (MSC).
14  * It is documented in the ARM CoreLink SIE-200 System IP for Embedded TRM
15  * (DDI 0571G):
16  * https://developer.arm.com/products/architecture/m-profile/docs/ddi0571/g
17  *
18  * The MSC sits in front of a device which can be a bus master (such as
19  * a DMA controller) and allows secure software to configure it to either
20  * pass through or reject transactions made by that bus master.
21  * Rejected transactions may be configured to either be aborted, or to
22  * behave as RAZ/WI. An interrupt can be signalled for a rejected transaction.
23  *
24  * The MSC has no register interface -- it is configured purely by a
25  * collection of input signals from other hardware in the system. Typically
26  * they are either hardwired or exposed in an ad-hoc register interface by
27  * the SoC that uses the MSC.
28  *
29  * We don't currently implement the irq_enable GPIO input, because on
30  * the MPS2 FPGA images it is always tied high, which is awkward to
31  * implement in QEMU.
32  *
33  * QEMU interface:
34  * + Named GPIO input "cfg_nonsec": set to 1 if the bus master should be
35  *   treated as nonsecure, or 0 for secure
36  * + Named GPIO input "cfg_sec_resp": set to 1 if a rejected transaction should
37  *   result in a transaction error, or 0 for the transaction to RAZ/WI
38  * + Named GPIO input "irq_clear": set to 1 to clear a pending interrupt
39  * + Named GPIO output "irq": set for a transaction-failed interrupt
40  * + Property "downstream": MemoryRegion defining where bus master transactions
41  *   are made if they are not blocked
42  * + Property "idau": an object implementing IDAUInterface, which defines which
43  *   addresses should be treated as secure and which as non-secure.
44  *   This need not be the same IDAU as the one used by the CPU.
45  * + sysbus MMIO region 0: MemoryRegion defining the upstream end of the MSC;
46  *   this should be passed to the bus master device as the region it should
47  *   make memory transactions to
48  */
49 
50 #ifndef TZ_MSC_H
51 #define TZ_MSC_H
52 
53 #include "hw/sysbus.h"
54 #include "target/arm/idau.h"
55 #include "qom/object.h"
56 
57 #define TYPE_TZ_MSC "tz-msc"
58 typedef struct TZMSC TZMSC;
59 DECLARE_INSTANCE_CHECKER(TZMSC, TZ_MSC,
60                          TYPE_TZ_MSC)
61 
62 struct TZMSC {
63     /*< private >*/
64     SysBusDevice parent_obj;
65 
66     /*< public >*/
67 
68     /* State: these just track the values of our input signals */
69     bool cfg_nonsec;
70     bool cfg_sec_resp;
71     bool irq_clear;
72     /* State: are we asserting irq ? */
73     bool irq_status;
74 
75     qemu_irq irq;
76     MemoryRegion *downstream;
77     AddressSpace downstream_as;
78     MemoryRegion upstream;
79     IDAUInterface *idau;
80 };
81 
82 #endif
83