Commit Graph

30 Commits

Author SHA1 Message Date
Markus Armbruster
d90b1e4236 hw/cxl: Clean up includes
This commit was created with scripts/clean-includes.

All .c should include qemu/osdep.h first.  The script performs three
related cleanups:

* Ensure .c files include qemu/osdep.h first.
* Including it in a .h is redundant, since the .c  already includes
  it.  Drop such inclusions.
* Likewise, including headers qemu/osdep.h includes is redundant.
  Drop these, too.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20230202133830.2152150-8-armbru@redhat.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-02-08 07:16:23 +01:00
Markus Armbruster
881e019770 include/hw/cxl: Break inclusion loop cxl_pci.h and cxl_cdat_h
hw/cxl/cxl_pci.h and hw/cxl/cxl_cdat.h include each other.  The former
doesn't actually need the latter, so drop that inclusion to break the
loop.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221222100330.380143-8-armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-01-08 01:54:22 -05:00
Markus Armbruster
edf5ca5dbe include/hw/pci: Split pci_device.h off pci.h
PCIDeviceClass and PCIDevice are defined in pci.h.  Many users of the
header don't actually need them.  Similar structs live in their own
headers: PCIBusClass and PCIBus in pci_bus.h, PCIBridge in
pci_bridge.h, PCIHostBridgeClass and PCIHostState in pci_host.h,
PCIExpressHost in pcie_host.h, and PCIERootPortClass, PCIEPort, and
PCIESlot in pcie_port.h.

Move PCIDeviceClass and PCIDeviceClass to new pci_device.h, along with
the code that needs them.  Adjust include directives.

This also enables the next commit.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221222100330.380143-6-armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-01-08 01:54:22 -05:00
Markus Armbruster
2ef0f219b5 include/hw/cxl: Include hw/cxl/*.h where needed
hw/cxl/cxl_component.h needs CDATObject from hw/cxl/cxl_cdat.h.

hw/cxl/cxl_device.h needs CXLComponentState from
hw/cxl/cxl_component.h.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20221222100330.380143-4-armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-01-08 01:54:22 -05:00
Markus Armbruster
65c326ce51 include/hw/cxl: Move typedef PXBDev to cxl.h, and put it to use
hw/cxl/cxl.h uses the PXBDev structure tag instead of the typedef
name.  The typedef name is defined in hw/pci/pci_bridge.h.  Its
inclusion was dropped in the previous commit to break an inclusion
loop.

Move the typedef to hw/cxl/cxl.h, and use it there.  Delete an extra
typedef in hw/pci-bridge/pci_expander_bridge.c.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221222100330.380143-3-armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-01-08 01:54:22 -05:00
Markus Armbruster
674b0a5784 include/hw/pci: Break inclusion loop pci_bridge.h and cxl.h
hw/pci/pci_bridge.h and hw/cxl/cxl.h include each other.

Fortunately, breaking the loop is merely a matter of deleting
unnecessary includes from headers, and adding them back in places
where they are now missing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221222100330.380143-2-armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-01-08 01:54:22 -05:00
Jonathan Cameron
882877fc35 hw/pci-bridge/cxl-upstream: Add a CDAT table access DOE
This Data Object Exchange Mailbox allows software to query the
latency and bandwidth between ports on the switch. For now
only provide information on routes between the upstream port and
each downstream port (not p2p).

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

--
Changes since v8: Mostly to match the type 3 equivalent
 - Move enum out of function and give it a more descriptive namespace.
Message-Id: <20221014151045.24781-6-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-11-07 13:12:19 -05:00
Huai-Cheng Kuo
aba578bdac hw/cxl/cdat: CXL CDAT Data Object Exchange implementation
The Data Object Exchange implementation of CXL Coherent Device Attribute
Table (CDAT). This implementation is referring to "Coherent Device
Attribute Table Specification, Rev. 1.03, July. 2022" and "Compute
Express Link Specification, Rev. 3.0, July. 2022"

This patch adds core support that will be shared by both
end-points and switch port emulation.

Signed-off-by: Huai-Cheng Kuo <hchkuo@avery-design.com.tw>
Signed-off-by: Chris Browy <cbrowy@avery-design.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20221014151045.24781-4-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-11-07 13:12:19 -05:00
Jonathan Cameron
9c769e0446 mem/cxl-type3: Add sn option to provide serial number for PCI ecap
The Device Serial Number Extended Capability PCI r6.0 sec 7.9.3
provides a standard way to provide a device serial number as
an IEEE defined 64-bit extended unique identifier EUI-64.

CXL 2.0 section 8.1.12.2 Memory Device PCIe Capabilities and
Extended Capabilities requires this to be used to uniquely
identify CXL memory devices.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20220923161835.9805-1-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Ben Widawsky <bwidawsk@kernel.org>
2022-10-09 16:38:45 -04:00
Jonathan Cameron
cb70b7e871 hw/cxl: Fix size of constant in interleave granularity function.
Whilst the interleave granularity is always small enough that this isn't
a real problem (much less than 4GiB) let's change the constant
to ULL to fix the coverity warning.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Fixes: 829de299d1 ("hw/cxl/component: Add utils for interleave parameter encoding/decoding")
Fixes: Coverity CID 1488868
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20220701132300.2264-4-Jonathan.Cameron@huawei.com>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-07-26 10:40:58 -04:00
Jonathan Cameron
638b752da3 pci-bridge/cxl_upstream: Add a CXL switch upstream port
An initial simple upstream port emulation to allow the creation
of CXL switches. The Device ID has been allocated for this use.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20220616145126.8002-2-Jonathan.Cameron@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-06-16 12:54:57 -04:00
Jonathan Cameron
7bd1900b36 pci/pci_expander_bridge: For CXL HB delay the HB register memory region setup.
As the CXLState will no long be accessible via MachineState
at time of PXB_CXL realization, come back later from the machine specific
code to fill in the missing memory region setup. Only at this stage
is it possible to check if cxl=on, so that check is moved to this
later point.

Note that for multiple host bridges, the allocation order of the
register spaces is changed. This will be reflected in ACPI CEDT.

Stubs are added to handle case of CONFIG_PXB=n for machines that
call these functions.

The bus walking logic is common to all machines so add a utility
function + stub to cxl-host*.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Message-Id: <20220608145440.26106-6-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-06-09 19:32:49 -04:00
Jonathan Cameron
dab390ff24 hw/cxl: Push linking of CXL targets into i386/pc rather than in machine.c
Whilst here take the oportunity to shorten the function name.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Message-Id: <20220608145440.26106-4-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-06-09 19:32:49 -04:00
Jonathan Cameron
03b39fcf64 hw/cxl: Make the CXL fixed memory window setup a machine parameter.
Paolo Bonzini requested this change to simplify the ongoing
effort to allow machine setup entirely via RPC.

Includes shortening the command line form cxl-fixed-memory-window
to cxl-fmw as the command lines are extremely long even with this
change.

The json change is needed to ensure that there is
a CXLFixedMemoryWindowOptionsList even though the actual
element in the json is never used. Similar to existing
SgxEpcProperties.

Update qemu-options.hx to reflect that this is now a -machine
parameter.  The bulk of -M / -machine parameters are documented
under machine, so use that in preference to M.

Update cxl-test and bios-tables-test to reflect new parameters.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Message-Id: <20220608145440.26106-2-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-06-09 19:32:49 -04:00
Jonathan Cameron
eb19d9079e cxl/cxl-host: Add memops for CFMWS region.
These memops perform interleave decoding, walking down the
CXL topology from CFMWS described host interleave
decoder via CXL host bridge HDM decoders, through the CXL
root ports and finally call CXL type 3 specific read and write
functions.

Note that, whilst functional the current implementation does
not support:
* switches
* multiple HDM decoders at a given level.
* unaligned accesses across the interleave boundaries

Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Message-Id: <20220429144110.25167-34-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 07:57:26 -04:00
Jonathan Cameron
5fcc499ee3 mem/cxl_type3: Add read and write functions for associated hostmem.
Once a read or write reaches a CXL type 3 device, the HDM decoders
on the device are used to establish the Device Physical Address
which should be accessed.  These functions peform the required maths
and then use a device specific address space to access the
hostmem->mr to fullfil the actual operation.  Note that failed writes
are silent, but failed reads return poison.  Note this is based
loosely on:

https://lore.kernel.org/qemu-devel/20200817161853.593247-6-f4bug@amsat.org/
[RFC PATCH 0/9] hw/misc: Add support for interleaved memory accesses

Only lightly tested so far.  More complex test cases yet to be written.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20220429144110.25167-33-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 07:57:26 -04:00
Jonathan Cameron
0b4aec2469 CXL/cxl_component: Add cxl_get_hb_cstate()
Accessor to get hold of the cxl state for a CXL host bridge
without exposing the internals of the implementation.

Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220429144110.25167-32-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 07:57:26 -04:00
Jonathan Cameron
aadfe32091 hw/cxl/host: Add support for CXL Fixed Memory Windows.
The concept of these is introduced in [1] in terms of the
description the CEDT ACPI table. The principal is more general.
Unlike once traffic hits the CXL root bridges, the host system
memory address routing is implementation defined and effectively
static once observable by standard / generic system software.
Each CXL Fixed Memory Windows (CFMW) is a region of PA space
which has fixed system dependent routing configured so that
accesses can be routed to the CXL devices below a set of target
root bridges. The accesses may be interleaved across multiple
root bridges.

For QEMU we could have fully specified these regions in terms
of a base PA + size, but as the absolute address does not matter
it is simpler to let individual platforms place the memory regions.

ExampleS:
-cxl-fixed-memory-window targets.0=cxl.0,size=128G
-cxl-fixed-memory-window targets.0=cxl.1,size=128G
-cxl-fixed-memory-window targets.0=cxl0,targets.1=cxl.1,size=256G,interleave-granularity=2k

Specifies
* 2x 128G regions not interleaved across root bridges, one for each of
  the root bridges with ids cxl.0 and cxl.1
* 256G region interleaved across root bridges with ids cxl.0 and cxl.1
with a 2k interleave granularity.

When system software enumerates the devices below a given root bridge
it can then decide which CFMW to use. If non interleave is desired
(or possible) it can use the appropriate CFMW for the root bridge in
question.  If there are suitable devices to interleave across the
two root bridges then it may use the 3rd CFMS.

A number of other designs were considered but the following constraints
made it hard to adapt existing QEMU approaches to this particular problem.
1) The size must be known before a specific architecture / board brings
   up it's PA memory map.  We need to set up an appropriate region.
2) Using links to the host bridges provides a clean command line interface
   but these links cannot be established until command line devices have
   been added.

Hence the two step process used here of first establishing the size,
interleave-ways and granularity + caching the ids of the host bridges
and then, once available finding the actual host bridges so they can
be used later to support interleave decoding.

[1] CXL 2.0 ECN: CEDT CFMWS & QTG DSM (computeexpresslink.org / specifications)

Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Acked-by: Markus Armbruster <armbru@redhat.com> # QAPI Schema
Message-Id: <20220429144110.25167-28-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 07:57:26 -04:00
Jonathan Cameron
829de299d1 hw/cxl/component: Add utils for interleave parameter encoding/decoding
Both registers and the CFMWS entries in CDAT use simple encodings
for the number of interleave ways and the interleave granularity.
Introduce simple conversion functions to/from the unencoded
number / size.  So far the iw decode has not been needed so is
it not implemented.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220429144110.25167-27-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
6e4e3ae936 hw/cxl/component: Implement host bridge MMIO (8.2.5, table 142)
CXL host bridges themselves may have MMIO. Since host bridges don't have
a BAR they are treated as special for MMIO.  This patch includes
i386/pc support.
Also hook up the device reset now that we have have the MMIO
space in which the results are visible.

Note that we duplicate the PCI express case for the aml_build but
the implementations will diverge when the CXL specific _OSC is
introduced.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Co-developed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220429144110.25167-24-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
3ebe676a34 hw/cxl/device: Implement get/set Label Storage Area (LSA)
Implement get and set handlers for the Label Storage Area
used to hold data describing persistent memory configuration
so that it can be ensured it is seen in the same configuration
after reboot.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20220429144110.25167-22-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
639daf8e93 hw/cxl/device: Plumb real Label Storage Area (LSA) sizing
This should introduce no change. Subsequent work will make use of this
new class member.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20220429144110.25167-21-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
e1706ea83d hw/cxl/device: Add a memory device (8.2.8.5)
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>
2022-05-13 06:13:36 -04:00
Jonathan Cameron
abb3009baf cxl: Machine level control on whether CXL support is enabled
There are going to be some potential overheads to CXL enablement,
for example the host bridge region reserved in memory maps.
Add a machine level control so that CXL is disabled by default.

Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220429144110.25167-14-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
557a79c83e hw/cxl/device: Timestamp implementation (8.2.9.3)
Errata F4 to CXL 2.0 clarified the meaning of the timer as the
sum of the value set with the timestamp set command and the number
of nano seconds since it was last set.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220429144110.25167-10-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
ce3b4e5c15 hw/cxl/device: Add memory device utilities
Memory devices implement extra capabilities on top of CXL devices. This
adds support for that.

A large part of memory devices is the mailbox/command interface. All of
the mailbox handling is done in the mailbox-utils library. Longer term,
new CXL devices that are being emulated may want to handle commands
differently, and therefore would need a mechanism to opt in/out of the
specific generic handlers. As such, this is considered sufficient for
now, but may need more depth in the future.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220429144110.25167-8-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
464e14ac43 hw/cxl/device: Implement basic mailbox (8.2.8.4)
This is the beginning of implementing mailbox support for CXL 2.0
devices. The implementation recognizes when the doorbell is rung,
handles the command/payload, clears the doorbell while returning error
codes and data.

Generally the mailbox mechanism is designed to permit communication
between the host OS and the firmware running on the device. For our
purposes, we emulate both the firmware, implemented primarily in
cxl-mailbox-utils.c, and the hardware.

No commands are implemented yet.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220429144110.25167-7-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
6364adacdf hw/cxl/device: Implement the CAP array (8.2.8.1-2)
This implements all device MMIO up to the first capability. That
includes the CXL Device Capabilities Array Register, as well as all of
the CXL Device Capability Header Registers. The latter are filled in as
they are implemented in the following patches.

Endianness and alignment are managed by softmmu memory core.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220429144110.25167-6-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
cd90126b4c hw/cxl/device: Introduce a CXL device (8.2.8)
A CXL device is a type of CXL component. Conceptually, a CXL device
would be a leaf node in a CXL topology. From an emulation perspective,
CXL devices are the most complex and so the actual implementation is
reserved for discrete commits.

This new device type is specifically catered towards the eventual
implementation of a Type3 CXL.mem device, 8.2.8.5 in the CXL 2.0
specification.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Adam Manzanares <a.manzanares@samsung.com>
Message-Id: <20220429144110.25167-5-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:36 -04:00
Ben Widawsky
9e58f52d3f hw/cxl/component: Introduce CXL components (8.1.x, 8.2.5)
A CXL 2.0 component is any entity in the CXL topology. All components
have a analogous function in PCIe. Except for the CXL host bridge, all
have a PCIe config space that is accessible via the common PCIe
mechanisms. CXL components are enumerated via DVSEC fields in the
extended PCIe header space. CXL components will minimally implement some
subset of CXL.mem and CXL.cache registers defined in 8.2.5 of the CXL
2.0 specification. Two headers and a utility library are introduced to
support the minimum functionality needed to enumerate components.

The cxl_pci header manages bits associated with PCI, specifically the
DVSEC and related fields. The cxl_component.h variant has data
structures and APIs that are useful for drivers implementing any of the
CXL 2.0 components. The library takes care of making use of the DVSEC
bits and the CXL.[mem|cache] registers. Per spec, the registers are
little endian.

None of the mechanisms required to enumerate a CXL capable hostbridge
are introduced at this point.

Note that the CXL.mem and CXL.cache registers used are always 4B wide.
It's possible in the future that this constraint will not hold.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Adam Manzanares <a.manzanares@samsung.com>
Message-Id: <20220429144110.25167-3-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-13 06:13:35 -04:00