Fast Models Reference Manual - ARM Information Center

Peripheral and Interface Components
Memory is stored in blocks of at least 4KB, so the returned pointer can access all
memory within a block. If a limit pointer is provided, it is used to return the
device address corresponding to the limit of the current block.
The pointer value returned is not guaranteed to remain valid indefinitely. Bus
activities, or other calls to the control port, might invalidate the pointer.
provideReadStorage(pv::bus_addr_t base, pv::bus_addr_t limit, const uint8_t * storage),
provideReadWriteStorage(pv::bus_addr_t base,pv::bus_addr_t limit, uint8_t * storage)
These methods enables you to allocate blocks of memory that the PVBusSlave
can use to manage regions of RAM/ROM. Only use these methods when you
require a high degree of control over memory, such as when you need a device to
map specific regions of host memory into the simulation.
You must align base (inclusive) and limit (exclusive) values to 4KB page
addresses within device address space. The memory region pointed to by storage
must be large enough to contain (limit - base) bytes.
After these calls, PVBusSlave controls access to the underlying memory. The
owner must call getWriteStorage() before modifying the memory contents and
getReadStorage() before reading the memory contents.
pv::accessMode values
The values assigned to pv::accessMode control what happens when an address is accessed. Legal
values for the enumeration are:
pv::ACCESSMODE_MEMORY
Act as memory. The PVBusSlave manages the underlying storage to provide 4KB
of memory, which can be ROM or RAM, depending on how you configure it to
handle bus write transactions.
pv::ACCESSMODE_DEVICE
Act as a device. Requests to the select pages are routed to the PVBusSlave device
port, where the necessary behavior can be implemented by the component.
pv::ACCESSMODE_ABORT
Generate bus abort signals for any accesses to this page.
pv::ACCESSMODE_IGNORE
Ignore accesses to this page. Bus read requests return 0.
Parameters
Table 5-6 provides a description of the configuration parameters for the PVBusSlave
component.
Table 5-6 PVBusSlave configuration parameters
Parameter
name
Description
Type
Allowed
value
Default
value
size
Addressable size of
the device in bytes.
Must be a multiple
of 0x1000 (4KB).
uint64_t 4KB to 4GB 0x10000000
(256MB)
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