qemu-e2k/hw/misc/tz-msc.c

309 lines
8.1 KiB
C

/*
* ARM TrustZone master security controller emulation
*
* Copyright (c) 2018 Linaro Limited
* Written by Peter Maydell
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 or
* (at your option) any later version.
*/
#include "qemu/osdep.h"
#include "qemu/log.h"
#include "qapi/error.h"
#include "trace.h"
#include "hw/sysbus.h"
#include "hw/registerfields.h"
#include "hw/misc/tz-msc.h"
static void tz_msc_update_irq(TZMSC *s)
{
bool level = s->irq_status;
trace_tz_msc_update_irq(level);
qemu_set_irq(s->irq, level);
}
static void tz_msc_cfg_nonsec(void *opaque, int n, int level)
{
TZMSC *s = TZ_MSC(opaque);
trace_tz_msc_cfg_nonsec(level);
s->cfg_nonsec = level;
}
static void tz_msc_cfg_sec_resp(void *opaque, int n, int level)
{
TZMSC *s = TZ_MSC(opaque);
trace_tz_msc_cfg_sec_resp(level);
s->cfg_sec_resp = level;
}
static void tz_msc_irq_clear(void *opaque, int n, int level)
{
TZMSC *s = TZ_MSC(opaque);
trace_tz_msc_irq_clear(level);
s->irq_clear = level;
if (level) {
s->irq_status = false;
tz_msc_update_irq(s);
}
}
/* The MSC may either block a transaction by aborting it, block a
* transaction by making it RAZ/WI, allow it through with
* MemTxAttrs indicating a secure transaction, or allow it with
* MemTxAttrs indicating a non-secure transaction.
*/
typedef enum MSCAction {
MSCBlockAbort,
MSCBlockRAZWI,
MSCAllowSecure,
MSCAllowNonSecure,
} MSCAction;
static MSCAction tz_msc_check(TZMSC *s, hwaddr addr)
{
/*
* Check whether to allow an access from the bus master, returning
* an MSCAction indicating the required behaviour. If the transaction
* is blocked, the caller must check cfg_sec_resp to determine
* whether to abort or RAZ/WI the transaction.
*/
IDAUInterfaceClass *iic = IDAU_INTERFACE_GET_CLASS(s->idau);
IDAUInterface *ii = IDAU_INTERFACE(s->idau);
bool idau_exempt = false, idau_ns = true, idau_nsc = true;
int idau_region = IREGION_NOTVALID;
iic->check(ii, addr, &idau_region, &idau_exempt, &idau_ns, &idau_nsc);
if (idau_exempt) {
/*
* Uncheck region -- OK, transaction type depends on
* whether bus master is configured as Secure or NonSecure
*/
return s->cfg_nonsec ? MSCAllowNonSecure : MSCAllowSecure;
}
if (idau_ns) {
/* NonSecure region -- always forward as NS transaction */
return MSCAllowNonSecure;
}
if (!s->cfg_nonsec) {
/* Access to Secure region by Secure bus master: OK */
return MSCAllowSecure;
}
/* Attempted access to Secure region by NS bus master: block */
trace_tz_msc_access_blocked(addr);
if (!s->cfg_sec_resp) {
return MSCBlockRAZWI;
}
/*
* The TRM isn't clear on behaviour if irq_clear is high when a
* transaction is blocked. We assume that the MSC behaves like the
* PPC, where holding irq_clear high suppresses the interrupt.
*/
if (!s->irq_clear) {
s->irq_status = true;
tz_msc_update_irq(s);
}
return MSCBlockAbort;
}
static MemTxResult tz_msc_read(void *opaque, hwaddr addr, uint64_t *pdata,
unsigned size, MemTxAttrs attrs)
{
TZMSC *s = opaque;
AddressSpace *as = &s->downstream_as;
uint64_t data;
MemTxResult res;
switch (tz_msc_check(s, addr)) {
case MSCBlockAbort:
return MEMTX_ERROR;
case MSCBlockRAZWI:
*pdata = 0;
return MEMTX_OK;
case MSCAllowSecure:
attrs.secure = 1;
attrs.unspecified = 0;
break;
case MSCAllowNonSecure:
attrs.secure = 0;
attrs.unspecified = 0;
break;
}
switch (size) {
case 1:
data = address_space_ldub(as, addr, attrs, &res);
break;
case 2:
data = address_space_lduw_le(as, addr, attrs, &res);
break;
case 4:
data = address_space_ldl_le(as, addr, attrs, &res);
break;
case 8:
data = address_space_ldq_le(as, addr, attrs, &res);
break;
default:
g_assert_not_reached();
}
*pdata = data;
return res;
}
static MemTxResult tz_msc_write(void *opaque, hwaddr addr, uint64_t val,
unsigned size, MemTxAttrs attrs)
{
TZMSC *s = opaque;
AddressSpace *as = &s->downstream_as;
MemTxResult res;
switch (tz_msc_check(s, addr)) {
case MSCBlockAbort:
return MEMTX_ERROR;
case MSCBlockRAZWI:
return MEMTX_OK;
case MSCAllowSecure:
attrs.secure = 1;
attrs.unspecified = 0;
break;
case MSCAllowNonSecure:
attrs.secure = 0;
attrs.unspecified = 0;
break;
}
switch (size) {
case 1:
address_space_stb(as, addr, val, attrs, &res);
break;
case 2:
address_space_stw_le(as, addr, val, attrs, &res);
break;
case 4:
address_space_stl_le(as, addr, val, attrs, &res);
break;
case 8:
address_space_stq_le(as, addr, val, attrs, &res);
break;
default:
g_assert_not_reached();
}
return res;
}
static const MemoryRegionOps tz_msc_ops = {
.read_with_attrs = tz_msc_read,
.write_with_attrs = tz_msc_write,
.endianness = DEVICE_LITTLE_ENDIAN,
};
static void tz_msc_reset(DeviceState *dev)
{
TZMSC *s = TZ_MSC(dev);
trace_tz_msc_reset();
s->cfg_sec_resp = false;
s->cfg_nonsec = false;
s->irq_clear = 0;
s->irq_status = 0;
}
static void tz_msc_init(Object *obj)
{
DeviceState *dev = DEVICE(obj);
TZMSC *s = TZ_MSC(obj);
qdev_init_gpio_in_named(dev, tz_msc_cfg_nonsec, "cfg_nonsec", 1);
qdev_init_gpio_in_named(dev, tz_msc_cfg_sec_resp, "cfg_sec_resp", 1);
qdev_init_gpio_in_named(dev, tz_msc_irq_clear, "irq_clear", 1);
qdev_init_gpio_out_named(dev, &s->irq, "irq", 1);
}
static void tz_msc_realize(DeviceState *dev, Error **errp)
{
Object *obj = OBJECT(dev);
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
TZMSC *s = TZ_MSC(dev);
const char *name = "tz-msc-downstream";
uint64_t size;
/*
* We can't create the upstream end of the port until realize,
* as we don't know the size of the MR used as the downstream until then.
* We insist on having a downstream, to avoid complicating the
* code with handling the "don't know how big this is" case. It's easy
* enough for the user to create an unimplemented_device as downstream
* if they have nothing else to plug into this.
*/
if (!s->downstream) {
error_setg(errp, "MSC 'downstream' link not set");
return;
}
if (!s->idau) {
error_setg(errp, "MSC 'idau' link not set");
return;
}
size = memory_region_size(s->downstream);
address_space_init(&s->downstream_as, s->downstream, name);
memory_region_init_io(&s->upstream, obj, &tz_msc_ops, s, name, size);
sysbus_init_mmio(sbd, &s->upstream);
}
static const VMStateDescription tz_msc_vmstate = {
.name = "tz-msc",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_BOOL(cfg_nonsec, TZMSC),
VMSTATE_BOOL(cfg_sec_resp, TZMSC),
VMSTATE_BOOL(irq_clear, TZMSC),
VMSTATE_BOOL(irq_status, TZMSC),
VMSTATE_END_OF_LIST()
}
};
static Property tz_msc_properties[] = {
DEFINE_PROP_LINK("downstream", TZMSC, downstream,
TYPE_MEMORY_REGION, MemoryRegion *),
DEFINE_PROP_LINK("idau", TZMSC, idau,
TYPE_IDAU_INTERFACE, IDAUInterface *),
DEFINE_PROP_END_OF_LIST(),
};
static void tz_msc_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = tz_msc_realize;
dc->vmsd = &tz_msc_vmstate;
dc->reset = tz_msc_reset;
dc->props = tz_msc_properties;
}
static const TypeInfo tz_msc_info = {
.name = TYPE_TZ_MSC,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(TZMSC),
.instance_init = tz_msc_init,
.class_init = tz_msc_class_init,
};
static void tz_msc_register_types(void)
{
type_register_static(&tz_msc_info);
}
type_init(tz_msc_register_types);