On 6/1/23 18:51, Peter Maydell wrote:
On Wed, 4 Jan 2023 at 22:04, Philippe Mathieu-Daudé <phi...@linaro.org> wrote:
Paving the road toward heterogeneous QEMU, the limitations of
having a single machine sysbus become more apparent.
The sysbus_mmio_map() API forces the caller to map a sysbus
device to an address on the system bus (system bus here is
the root MemoryRegion returned by get_system_memory() ).
This is not practical when each core has its own address
space and group of cores have access to a part of the
peripherals.
Experimenting with the PFLASH devices. Here the fix is
quite easy, we split the pflash_cfi_register() -- which
does the implicit sysbus mapping -- into an explicit qdev
pflash_cfi_create() followed by the sysbus_mmio_map() call.
pflash_cfi_register() is a legacy convenience function. If
you don't like the sysbus_mmio_map() it does then you can
create, configure, realize and map the device directly.
This is what hw/arm/virt.c does, for instance (it wants to
map the flash devices into either secure or non secure RAM).
Good point, thanks!
