include/hw/misc/tz-ppc.h

   1 /*
   2  * ARM TrustZone peripheral protection 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 /* This is a model of the TrustZone peripheral protection controller (PPC).
  13  * It is documented in the ARM CoreLink SIE-200 System IP for Embedded TRM
  14  * (DDI 0571G):
  15  * https://developer.arm.com/products/architecture/m-profile/docs/ddi0571/g
  16  *
  17  * The PPC sits in front of peripherals and allows secure software to
  18  * configure it to either pass through or reject transactions.
  19  * Rejected transactions may be configured to either be aborted, or to
  20  * behave as RAZ/WI. An interrupt can be signalled for a rejected transaction.
  21  *
  22  * The PPC has no register interface -- it is configured purely by a
  23  * collection of input signals from other hardware in the system. Typically
  24  * they are either hardwired or exposed in an ad-hoc register interface by
  25  * the SoC that uses the PPC.
  26  *
  27  * This QEMU model can be used to model either the AHB5 or APB4 TZ PPC,
  28  * since the only difference between them is that the AHB version has a
  29  * "default" port which has no security checks applied. In QEMU the default
  30  * port can be emulated simply by wiring its downstream devices directly
  31  * into the parent address space, since the PPC does not need to intercept
  32  * transactions there.
  33  *
  34  * In the hardware, selection of which downstream port to use is done by
  35  * the user's decode logic asserting one of the hsel[] signals. In QEMU,
  36  * we provide 16 MMIO regions, one per port, and the user maps these into
  37  * the desired addresses to implement the address decode.
  38  *
  39  * QEMU interface:
  40  * + sysbus MMIO regions 0..15: MemoryRegions defining the upstream end
  41  *   of each of the 16 ports of the PPC. When a port is unused (i.e. no
  42  *   downstream MemoryRegion is connected to it) at the end of the 0..15
  43  *   range then no sysbus MMIO region is created for its upstream. When an
  44  *   unused port lies in the middle of the range with other used ports at
  45  *   higher port numbers, a dummy MMIO region is created to ensure that
  46  *   port N's upstream is always sysbus MMIO region N. Dummy regions should
  47  *   not be mapped, and will assert if any access is made to them.
  48  * + Property "port[0..15]": MemoryRegion defining the downstream device(s)
  49  *   for each of the 16 ports of the PPC
  50  * + Named GPIO inputs "cfg_nonsec[0..15]": set to 1 if the port should be
  51  *   accessible to NonSecure transactions
  52  * + Named GPIO inputs "cfg_ap[0..15]": set to 1 if the port should be
  53  *   accessible to non-privileged transactions
  54  * + Named GPIO input "cfg_sec_resp": set to 1 if a rejected transaction should
  55  *   result in a transaction error, or 0 for the transaction to RAZ/WI
  56  * + Named GPIO input "irq_enable": set to 1 to enable interrupts
  57  * + Named GPIO input "irq_clear": set to 1 to clear a pending interrupt
  58  * + Named GPIO output "irq": set for a transaction-failed interrupt
  59  * + Property "NONSEC_MASK": if a bit is set in this mask then accesses to
  60  *   the associated port do not have the TZ security check performed. (This
  61  *   corresponds to the hardware allowing this to be set as a Verilog
  62  *   parameter.)
  63  */
  64
  65 #ifndef TZ_PPC_H
  66 #define TZ_PPC_H
  67
  68 #include "hw/sysbus.h"
  69 #include "qom/object.h"
  70
  71 #define TYPE_TZ_PPC "tz-ppc"
  72 OBJECT_DECLARE_SIMPLE_TYPE(TZPPC, TZ_PPC)
  73
  74 #define TZ_NUM_PORTS 16
  75
  76
  77 typedef struct TZPPCPort {
  78     TZPPC *ppc;
  79     MemoryRegion upstream;
  80     AddressSpace downstream_as;
  81     MemoryRegion *downstream;
  82 } TZPPCPort;
  83
  84 struct TZPPC {
  85     /*< private >*/
  86     SysBusDevice parent_obj;
  87
  88     /*< public >*/
  89
  90     /* State: these just track the values of our input signals */
  91     bool cfg_nonsec[TZ_NUM_PORTS];
  92     bool cfg_ap[TZ_NUM_PORTS];
  93     bool cfg_sec_resp;
  94     bool irq_enable;
  95     bool irq_clear;
  96     /* State: are we asserting irq ? */
  97     bool irq_status;
  98
  99     qemu_irq irq;
 100
 101     /* Properties */
 102     uint32_t nonsec_mask;
 103
 104     TZPPCPort port[TZ_NUM_PORTS];
 105 };
 106
 107 #endif