A CXL memory device (AKA Type 3) is a CXL component that contains some
combination of volatile and persistent memory. It also implements the
previously defined mailbox interface as well as the memory device
firmware interface.
Although the memory device is configured like a normal PCIe device, the
memory traffic is on an entirely separate bus conceptually (using the
same physical wires as PCIe, but different protocol).
Once the CXL topology is fully configure and address decoders committed,
the guest physical address for the memory device is part of a larger
window which is owned by the platform. The creation of these windows
is later in this series.
The following example will create a 256M device in a 512M window:
-object "memory-backend-file,id=cxl-mem1,share,mem-path=cxl-type3,size=512M"
-device "cxl-type3,bus=rp0,memdev=cxl-mem1,id=cxl-pmem0"
Note: Dropped PCDIMM info interfaces for now. They can be added if
appropriate at a later date.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20220429144110.25167-18-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Pass CONFIG_FUZZ via host_kconfig, and use it to select the
sparse-mem device.
Cc: Alexander Oleinik <alxndr@bu.edu>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20211007130829.632254-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
sparse-mem.c is added to the 'mem_ss' source set, which itself
is conditionally added to softmmu_ss if CONFIG_MEM_DEVICE is
selected.
But if CONFIG_MEM_DEVICE isn't selected, we get a link failure
even if CONFIG_FUZZ is selected:
/usr/bin/ld: tests_qtest_fuzz_generic_fuzz.c.o: in function `generic_pre_fuzz':
tests/qtest/fuzz/generic_fuzz.c:826: undefined reference to `sparse_mem_init'
clang-10: error: linker command failed with exit code 1 (use -v to see invocation)
Fix by adding sparse-mem.c directly to the softmmu_ss set.
Fixes: 230376d285 ("memory: add a sparse memory device for fuzzing")
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20210406133944.4193691-1-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
For testing, it can be useful to simulate an enormous amount of memory
(e.g. 2^64 RAM). This adds an MMIO device that acts as sparse memory.
When something writes a nonzero value to a sparse-mem address, we
allocate a block of memory. For now, since the only user of this device
is the fuzzer, we do not track and free zeroed blocks. The device has a
very low priority (so it can be mapped beneath actual RAM, and virtual
device MMIO regions).
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This just implements the bare minimum to cause the boot block to skip
memory initialization.
Reviewed-by: Tyrone Ting <kfting@nuvoton.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Havard Skinnemoen <hskinnemoen@google.com>
Message-id: 20200911052101.2602693-10-hskinnemoen@google.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>