qemu/hw/arm/armv7m.c
Peter Maydell a724377a11 hw/intc/armv7m_nvic: Make all of system PPB range be RAZWI/BusFault
For M-profile CPUs, the range from 0xe0000000 to 0xe00fffff is the
Private Peripheral Bus range, which includes all of the memory mapped
devices and registers that are part of the CPU itself, including the
NVIC, systick timer, and debug and trace components like the Data
Watchpoint and Trace unit (DWT).  Within this large region, the range
0xe000e000 to 0xe000efff is the System Control Space (NVIC, system
registers, systick) and 0xe002e000 to 0exe002efff is its Non-secure
alias.

The architecture is clear that within the SCS unimplemented registers
should be RES0 for privileged accesses and generate BusFault for
unprivileged accesses, and we currently implement this.

It is less clear about how to handle accesses to unimplemented
regions of the wider PPB.  Unprivileged accesses should definitely
cause BusFaults (R_DQQS), but the behaviour of privileged accesses is
not given as a general rule.  However, the register definitions of
individual registers for components like the DWT all state that they
are RES0 if the relevant component is not implemented, so the
simplest way to provide that is to provide RAZ/WI for the whole range
for privileged accesses.  (The v7M Arm ARM does say that reserved
registers should be UNK/SBZP.)

Expand the container MemoryRegion that the NVIC exposes so that
it covers the whole PPB space. This means:
 * moving the address that the ARMV7M device maps it to down by
   0xe000 bytes
 * moving the off and the offsets within the container of all the
   subregions forward by 0xe000 bytes
 * adding a new default MemoryRegion that covers the whole container
   at a lower priority than anything else and which provides the
   RAZWI/BusFault behaviour

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-2-peter.maydell@linaro.org
2020-12-10 11:44:55 +00:00

368 lines
11 KiB
C

/*
* ARMV7M System emulation.
*
* Copyright (c) 2006-2007 CodeSourcery.
* Written by Paul Brook
*
* This code is licensed under the GPL.
*/
#include "qemu/osdep.h"
#include "hw/arm/armv7m.h"
#include "qapi/error.h"
#include "cpu.h"
#include "hw/sysbus.h"
#include "hw/arm/boot.h"
#include "hw/loader.h"
#include "hw/qdev-properties.h"
#include "elf.h"
#include "sysemu/qtest.h"
#include "sysemu/reset.h"
#include "qemu/error-report.h"
#include "qemu/module.h"
#include "exec/address-spaces.h"
#include "target/arm/idau.h"
/* Bitbanded IO. Each word corresponds to a single bit. */
/* Get the byte address of the real memory for a bitband access. */
static inline hwaddr bitband_addr(BitBandState *s, hwaddr offset)
{
return s->base | (offset & 0x1ffffff) >> 5;
}
static MemTxResult bitband_read(void *opaque, hwaddr offset,
uint64_t *data, unsigned size, MemTxAttrs attrs)
{
BitBandState *s = opaque;
uint8_t buf[4];
MemTxResult res;
int bitpos, bit;
hwaddr addr;
assert(size <= 4);
/* Find address in underlying memory and round down to multiple of size */
addr = bitband_addr(s, offset) & (-size);
res = address_space_read(&s->source_as, addr, attrs, buf, size);
if (res) {
return res;
}
/* Bit position in the N bytes read... */
bitpos = (offset >> 2) & ((size * 8) - 1);
/* ...converted to byte in buffer and bit in byte */
bit = (buf[bitpos >> 3] >> (bitpos & 7)) & 1;
*data = bit;
return MEMTX_OK;
}
static MemTxResult bitband_write(void *opaque, hwaddr offset, uint64_t value,
unsigned size, MemTxAttrs attrs)
{
BitBandState *s = opaque;
uint8_t buf[4];
MemTxResult res;
int bitpos, bit;
hwaddr addr;
assert(size <= 4);
/* Find address in underlying memory and round down to multiple of size */
addr = bitband_addr(s, offset) & (-size);
res = address_space_read(&s->source_as, addr, attrs, buf, size);
if (res) {
return res;
}
/* Bit position in the N bytes read... */
bitpos = (offset >> 2) & ((size * 8) - 1);
/* ...converted to byte in buffer and bit in byte */
bit = 1 << (bitpos & 7);
if (value & 1) {
buf[bitpos >> 3] |= bit;
} else {
buf[bitpos >> 3] &= ~bit;
}
return address_space_write(&s->source_as, addr, attrs, buf, size);
}
static const MemoryRegionOps bitband_ops = {
.read_with_attrs = bitband_read,
.write_with_attrs = bitband_write,
.endianness = DEVICE_NATIVE_ENDIAN,
.impl.min_access_size = 1,
.impl.max_access_size = 4,
.valid.min_access_size = 1,
.valid.max_access_size = 4,
};
static void bitband_init(Object *obj)
{
BitBandState *s = BITBAND(obj);
SysBusDevice *dev = SYS_BUS_DEVICE(obj);
memory_region_init_io(&s->iomem, obj, &bitband_ops, s,
"bitband", 0x02000000);
sysbus_init_mmio(dev, &s->iomem);
}
static void bitband_realize(DeviceState *dev, Error **errp)
{
BitBandState *s = BITBAND(dev);
if (!s->source_memory) {
error_setg(errp, "source-memory property not set");
return;
}
address_space_init(&s->source_as, s->source_memory, "bitband-source");
}
/* Board init. */
static const hwaddr bitband_input_addr[ARMV7M_NUM_BITBANDS] = {
0x20000000, 0x40000000
};
static const hwaddr bitband_output_addr[ARMV7M_NUM_BITBANDS] = {
0x22000000, 0x42000000
};
static void armv7m_instance_init(Object *obj)
{
ARMv7MState *s = ARMV7M(obj);
int i;
/* Can't init the cpu here, we don't yet know which model to use */
memory_region_init(&s->container, obj, "armv7m-container", UINT64_MAX);
object_initialize_child(obj, "nvnic", &s->nvic, TYPE_NVIC);
object_property_add_alias(obj, "num-irq",
OBJECT(&s->nvic), "num-irq");
for (i = 0; i < ARRAY_SIZE(s->bitband); i++) {
object_initialize_child(obj, "bitband[*]", &s->bitband[i],
TYPE_BITBAND);
}
}
static void armv7m_realize(DeviceState *dev, Error **errp)
{
ARMv7MState *s = ARMV7M(dev);
SysBusDevice *sbd;
Error *err = NULL;
int i;
if (!s->board_memory) {
error_setg(errp, "memory property was not set");
return;
}
memory_region_add_subregion_overlap(&s->container, 0, s->board_memory, -1);
s->cpu = ARM_CPU(object_new_with_props(s->cpu_type, OBJECT(s), "cpu",
&err, NULL));
if (err != NULL) {
error_propagate(errp, err);
return;
}
object_property_set_link(OBJECT(s->cpu), "memory", OBJECT(&s->container),
&error_abort);
if (object_property_find(OBJECT(s->cpu), "idau")) {
object_property_set_link(OBJECT(s->cpu), "idau", s->idau,
&error_abort);
}
if (object_property_find(OBJECT(s->cpu), "init-svtor")) {
if (!object_property_set_uint(OBJECT(s->cpu), "init-svtor",
s->init_svtor, errp)) {
return;
}
}
if (object_property_find(OBJECT(s->cpu), "start-powered-off")) {
if (!object_property_set_bool(OBJECT(s->cpu), "start-powered-off",
s->start_powered_off, errp)) {
return;
}
}
if (object_property_find(OBJECT(s->cpu), "vfp")) {
if (!object_property_set_bool(OBJECT(s->cpu), "vfp", s->vfp, errp)) {
return;
}
}
if (object_property_find(OBJECT(s->cpu), "dsp")) {
if (!object_property_set_bool(OBJECT(s->cpu), "dsp", s->dsp, errp)) {
return;
}
}
/*
* Tell the CPU where the NVIC is; it will fail realize if it doesn't
* have one. Similarly, tell the NVIC where its CPU is.
*/
s->cpu->env.nvic = &s->nvic;
s->nvic.cpu = s->cpu;
if (!qdev_realize(DEVICE(s->cpu), NULL, errp)) {
return;
}
/* Note that we must realize the NVIC after the CPU */
if (!sysbus_realize(SYS_BUS_DEVICE(&s->nvic), errp)) {
return;
}
/* Alias the NVIC's input and output GPIOs as our own so the board
* code can wire them up. (We do this in realize because the
* NVIC doesn't create the input GPIO array until realize.)
*/
qdev_pass_gpios(DEVICE(&s->nvic), dev, NULL);
qdev_pass_gpios(DEVICE(&s->nvic), dev, "SYSRESETREQ");
qdev_pass_gpios(DEVICE(&s->nvic), dev, "NMI");
/* Wire the NVIC up to the CPU */
sbd = SYS_BUS_DEVICE(&s->nvic);
sysbus_connect_irq(sbd, 0,
qdev_get_gpio_in(DEVICE(s->cpu), ARM_CPU_IRQ));
memory_region_add_subregion(&s->container, 0xe0000000,
sysbus_mmio_get_region(sbd, 0));
for (i = 0; i < ARRAY_SIZE(s->bitband); i++) {
if (s->enable_bitband) {
Object *obj = OBJECT(&s->bitband[i]);
SysBusDevice *sbd = SYS_BUS_DEVICE(&s->bitband[i]);
if (!object_property_set_int(obj, "base",
bitband_input_addr[i], errp)) {
return;
}
object_property_set_link(obj, "source-memory",
OBJECT(s->board_memory), &error_abort);
if (!sysbus_realize(SYS_BUS_DEVICE(obj), errp)) {
return;
}
memory_region_add_subregion(&s->container, bitband_output_addr[i],
sysbus_mmio_get_region(sbd, 0));
} else {
object_unparent(OBJECT(&s->bitband[i]));
}
}
}
static Property armv7m_properties[] = {
DEFINE_PROP_STRING("cpu-type", ARMv7MState, cpu_type),
DEFINE_PROP_LINK("memory", ARMv7MState, board_memory, TYPE_MEMORY_REGION,
MemoryRegion *),
DEFINE_PROP_LINK("idau", ARMv7MState, idau, TYPE_IDAU_INTERFACE, Object *),
DEFINE_PROP_UINT32("init-svtor", ARMv7MState, init_svtor, 0),
DEFINE_PROP_BOOL("enable-bitband", ARMv7MState, enable_bitband, false),
DEFINE_PROP_BOOL("start-powered-off", ARMv7MState, start_powered_off,
false),
DEFINE_PROP_BOOL("vfp", ARMv7MState, vfp, true),
DEFINE_PROP_BOOL("dsp", ARMv7MState, dsp, true),
DEFINE_PROP_END_OF_LIST(),
};
static void armv7m_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = armv7m_realize;
device_class_set_props(dc, armv7m_properties);
}
static const TypeInfo armv7m_info = {
.name = TYPE_ARMV7M,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(ARMv7MState),
.instance_init = armv7m_instance_init,
.class_init = armv7m_class_init,
};
static void armv7m_reset(void *opaque)
{
ARMCPU *cpu = opaque;
cpu_reset(CPU(cpu));
}
void armv7m_load_kernel(ARMCPU *cpu, const char *kernel_filename, int mem_size)
{
int image_size;
uint64_t entry;
int big_endian;
AddressSpace *as;
int asidx;
CPUState *cs = CPU(cpu);
#ifdef TARGET_WORDS_BIGENDIAN
big_endian = 1;
#else
big_endian = 0;
#endif
if (arm_feature(&cpu->env, ARM_FEATURE_EL3)) {
asidx = ARMASIdx_S;
} else {
asidx = ARMASIdx_NS;
}
as = cpu_get_address_space(cs, asidx);
if (kernel_filename) {
image_size = load_elf_as(kernel_filename, NULL, NULL, NULL,
&entry, NULL, NULL,
NULL, big_endian, EM_ARM, 1, 0, as);
if (image_size < 0) {
image_size = load_image_targphys_as(kernel_filename, 0,
mem_size, as);
}
if (image_size < 0) {
error_report("Could not load kernel '%s'", kernel_filename);
exit(1);
}
}
/* CPU objects (unlike devices) are not automatically reset on system
* reset, so we must always register a handler to do so. Unlike
* A-profile CPUs, we don't need to do anything special in the
* handler to arrange that it starts correctly.
* This is arguably the wrong place to do this, but it matches the
* way A-profile does it. Note that this means that every M profile
* board must call this function!
*/
qemu_register_reset(armv7m_reset, cpu);
}
static Property bitband_properties[] = {
DEFINE_PROP_UINT32("base", BitBandState, base, 0),
DEFINE_PROP_LINK("source-memory", BitBandState, source_memory,
TYPE_MEMORY_REGION, MemoryRegion *),
DEFINE_PROP_END_OF_LIST(),
};
static void bitband_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = bitband_realize;
device_class_set_props(dc, bitband_properties);
}
static const TypeInfo bitband_info = {
.name = TYPE_BITBAND,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(BitBandState),
.instance_init = bitband_init,
.class_init = bitband_class_init,
};
static void armv7m_register_types(void)
{
type_register_static(&bitband_info);
type_register_static(&armv7m_info);
}
type_init(armv7m_register_types)