The three objects 'struct cxl_nvdimm_bridge', 'struct cxl_nvdimm', and
'struct cxl_pmem_region' manage CXL persistent memory resources. The
bridge represents base platform resources, the nvdimm represents one or
more endpoints, and the region is a collection of nvdimms that
contribute to an assembled address range.
Their relationship is such that a region is torn down if any component
endpoints are removed. All regions and endpoints are torn down if the
foundational bridge device goes down.
A workqueue was deployed to manage these interdependencies, but it is
difficult to reason about, and fragile. A recent attempt to take the CXL
root device lock in the cxl_mem driver was reported by lockdep as
colliding with the flush_work() in the cxl_pmem flows.
Instead of the workqueue, arrange for all pmem/nvdimm devices to be torn
down immediately and hierarchically. A similar change is made to both
the 'cxl_nvdimm' and 'cxl_pmem_region' objects. For bisect-ability both
changes are made in the same patch which unfortunately makes the patch
bigger than desired.
Arrange for cxl_memdev and cxl_region to register a cxl_nvdimm and
cxl_pmem_region as a devres release action of the bridge device.
Additionally, include a devres release action of the cxl_memdev or
cxl_region device that triggers the bridge's release action if an endpoint
exits before the bridge. I.e. this allows either unplugging the bridge,
or unplugging and endpoint to result in the same cleanup actions.
To keep the patch smaller the cleanup of the now defunct workqueue
infrastructure is saved for a follow-on patch.
Tested-by: Robert Richter <rrichter@amd.com>
Link: https://lore.kernel.org/r/166993041773.1882361.16444301376147207609.stgit@dwillia2-xfh.jf.intel.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The PCIE Data Object Exchange (DOE) mailbox is a protocol run over
configuration cycles. It assumes one initiator at a time. While the
kernel has control of the mailbox user space writes could interfere with
the kernel access.
Mark DOE mailbox config space exclusive when iterated by the CXL driver.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20220926215711.2893286-3-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
DOE mailbox objects will be needed for various mailbox communications
with each memory device.
Iterate each DOE mailbox capability and create PCI DOE mailbox objects
as found.
It is not anticipated that this is the final resting place for the
iteration of the DOE devices. The support of switch ports will drive
this code into the PCIe side. In this imagined architecture the CXL
port driver would then query into the PCI device for the DOE mailbox
array.
For now creating the mailboxes in the CXL port is good enough for the
endpoints. Later PCIe ports will need to support this to support switch
ports more generically.
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20220719205249.566684-5-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
To date the per-device-partition DPA range information has only been
used for enumeration purposes. In preparation for allocating regions
from available DPA capacity, convert those ranges into DPA-type resource
trees.
With resources and the new add_dpa_res() helper some open coded end
address calculations and debug prints can be cleaned.
The 'cxlds->pmem_res' and 'cxlds->ram_res' resources are child resources
of the total-device DPA space and they in turn will host DPA allocations
from cxl_endpoint_decoder instances (tracked by cxled->dpa_res).
Cc: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/165603878921.551046.8127845916514734142.stgit@dwillia2-xfh
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for fixing the setting of the 'mem_enabled' bit in CXL
DVSEC Control register, move all CXL DVSEC range enumeration into the
same source file.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/165291688886.1426646.15046138604010482084.stgit@dwillia2-xfh
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Allow cxl_await_media_ready() to be mocked for testing purposes rather
than carrying the maintenance burden of an indirect function call in the
mainline driver.
With the move cxl_await_media_ready() can no longer reuse the mailbox
timeout override, so add a media_ready_timeout module parameter to the
core to backfill.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/165291688340.1426646.4755627801983775011.stgit@dwillia2-xfh
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
A check mem_info_valid already happens in __cxl_dvsec_ranges(). Rely on
that instead of calling wait_for_valid again.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/165291686632.1426646.7479581732894574486.stgit@dwillia2-xfh
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that wait_for_media() does nothing supplemental to
wait_for_media_ready() just promote wait_for_media_ready() to a common
helper and drop wait_for_media().
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/165291686046.1426646.4390664747934592185.stgit@dwillia2-xfh
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
cxl_dvsec_ranges(), the helper for enumerating the presence of an active
legacy CXL.mem configuration on a CXL 2.0 Memory Expander, is not fatal
for cxl_pci because there is still value to enable mailbox operations
even if CXL.mem operation is disabled. Recall that the reason cxl_pci
does this initialization and not cxl_mem is to preserve the useful
property (for unit testing) that cxl_mem is cxl_memdev + mmio generic,
and does not require access to a 'struct pci_dev' to issue config
cycles.
Update 'struct cxl_endpoint_dvsec_info' to carry either a positive
number of non-zero size legacy CXL DVSEC ranges, or the negative error
code from __cxl_dvsec_ranges() in its @ranges member.
Reported-by: Krzysztof Zach <krzysztof.zach@intel.com>
Fixes: 560f785590 ("cxl/pci: Retrieve CXL DVSEC memory info")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/164730735869.3806189.4032428192652531946.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for not treating DVSEC range initialization failures as
fatal to cxl_pci_probe() add individual dev_dbg() statements for each of
the major failure reasons in cxl_dvsec_ranges().
The rationale for cxl_dvsec_ranges() failure not being fatal is that
there is still value for cxl_pci to enable mailbox operations even if
CXL.mem operation is disabled.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/164730734812.3806189.2726330688692684104.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Use the global cxl_mbox_cmd_rc table to improve debug messaging
in __cxl_pci_mbox_send_cmd() and allow cxl_mbox_send_cmd()
to map to proper kernel style errno codes - this patch
continues to use -ENXIO only so no change in semantics.
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed by: Adam Manzanares <a.manzanares@samsung.com>
Link: https://lore.kernel.org/r/20220404021216.66841-5-dave@stgolabs.net
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Upon a completed command the caller is still expected to check
the actual return_code register to ensure it succeed. This
adds, per the spec, the potential command return codes. It maps
the hardware return code with the kernel's errno style, and by
default continues to use -ENXIO (Command completed, but device
reported an error).
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed by: Adam Manzanares <a.manzanares@samsung.com>
Link: https://lore.kernel.org/r/20220404021216.66841-4-dave@stgolabs.net
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Also mention the need for the caller to check against any
errors from the hardware in return_code.
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed by: Adam Manzanares <a.manzanares@samsung.com>
Link: https://lore.kernel.org/r/20220404021216.66841-3-dave@stgolabs.net
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Per the CXL specification (8.1.12.2 Memory Device PCIe Capabilities and
Extended Capabilities) the Device Serial Number capability is mandatory.
Emit it for user tooling to identify devices.
It is reasonable to ask whether the attribute should be added to the
list of PCI sysfs device attributes. The PCI layer can optionally emit
it too, but the CXL subsystem is aiming to preserve its independence and
the possibility of CXL topologies with non-PCI devices in it. To date
that has only proven useful for the 'cxl_test' model, but as can be seen
with seen with ACPI0016 devices, sometimes all that is needed is a
platform firmware table to point to CXL Component Registers in MMIO
space to define a "CXL" device.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/164366608838.196598.16856227191534267098.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
CXL 2.0 8.1.3.8.2 states:
Memory_Active: When set, indicates that the CXL Range 1 memory is
fully initialized and available for software use. Must be set within
Range 1. Memory_Active_Timeout of deassertion of reset to CXL device
if CXL.mem HwInit Mode=1
Unfortunately, Memory_Active can take quite a long time depending on
media size (up to 256s per 2.0 spec). Provide a callback for the
eventual establishment of CXL.mem operations via the 'cxl_mem' driver
the 'struct cxl_memdev'. The implementation waits for 60s by default for
now and can be overridden by the mbox_ready_time module parameter.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
[djbw: switch to sleeping wait]
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/164298427373.3018233.9309741847039301834.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Before CXL 2.0 HDM Decoder Capability mechanisms can be utilized in a
device the driver must determine that the device is ready for CXL.mem
operation and that platform firmware, or some other agent, has
established an active decode via the legacy CXL 1.1 decoder mechanism.
This legacy mechanism is defined in the CXL DVSEC as a set of range
registers and status bits that take time to settle after a reset.
Validate the CXL memory decode setup via the DVSEC and cache it for
later consideration by the cxl_mem driver (to be added). Failure to
validate is not fatal to the cxl_pci driver since that is only providing
CXL command support over PCI.mmio, and might be needed to rectify CXL
DVSEC validation problems.
Any potential ranges that the device is already claiming via DVSEC need
to be reconciled with the dynamic provisioning ranges provided by
platform firmware (like ACPI CEDT.CFMWS). Leave that reconciliation to
the cxl_mem driver.
[djbw: shorten defines]
[djbw: change precise spin wait to generous msleep]
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
[djbw: clarify changelog]
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/164375911821.559935.7375160041663453400.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The PCIe device DVSEC, defined in the CXL 2.0 spec, 8.1.3 is required to
be implemented by CXL 2.0 endpoint devices. In preparation for consuming
this information in a new cxl_mem driver, retrieve the CXL DVSEC
position and warn about the implications of not finding it. Allow for
mailbox operation even if the CXL DVSEC is missing.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/164375309615.513620.7874131241128599893.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for defining a cxl_port object to represent the decoder
resources of a memory expander capture the component register base
address.
The port driver uses the component register base to enumerate the HDM
Decoder Capability structure. Unlike other cxl_port objects the endpoint
port decodes from upstream SPA to downstream DPA rather than upstream
port to downstream port.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
[djbw: clarify changelog]
Link: https://lore.kernel.org/r/164375084181.484304.3919737667590006795.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Similar to the mem.h rename, if the core wants to reuse definitions from
drivers/cxl/pci.h it is unable to use <pci.h> as that collides with
archs that have an arch/$arch/include/asm/pci.h, like MIPS.
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/164298422510.3018233.14693126572756675563.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This implements the TODO in cxl_acpi for mapping component registers.
cxl_acpi becomes the second consumer of CXL register block enumeration
(cxl_pci being the first). Moving the functionality to cxl_core allows
both of these drivers to use the functionality. Equally importantly it
allows cxl_core to use the functionality in the future.
CXL 2.0 root ports are similar to CXL 2.0 Downstream Ports with the main
distinction being they're a part of the CXL 2.0 host bridge. While
mapping their component registers is not immediately useful for the CXL
drivers, the movement of register block enumeration into core is a vital
step towards HDM decoder programming.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
[djbw: fix cxl_regmap_to_base() failure cases]
Link: https://lore.kernel.org/r/164298415080.3018233.14694957480228676592.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Get a better naming scheme in place for upcoming additions. By dropping
redundant usages of CXL and DVSEC where appropriate we can get more
concise and also more grepable defines.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/164298414022.3018233.15522855498759815097.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Device status can change without warning at any point in time. This
effectively means that no amount of status checking before a command is
submitted can guarantee that the device is not in an error condition
when the command is later submitted. The clearest signal that a device
is not able to process commands is if it fails to process commands.
With the above understanding in hand, update cxl_pci_setup_mailbox() to
validate the readiness of the mailbox once at the beginning of time, and
then use timeouts and busy sequencing errors as the only occasions to
report status.
Just as before, unless and until the driver gains a reset recovery path,
doorbell clearing failures by the device are fatal to mailbox
operations.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/164298413480.3018233.9643395389297971819.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The original driver implementation used the doorbell timeout for the
Mailbox Interface Ready bit to piggy back off of, since the latter does
not have a defined timeout. This functionality, introduced in commit
8adaf747c9 ("cxl/mem: Find device capabilities"), needs improvement as
the recent "Add Mailbox Ready Time" ECN timeout indicates that the
mailbox ready time can be significantly longer that 2 seconds.
While the specification limits the maximum timeout to 256s, the cxl_pci
driver gives up on the mailbox after 60s. This value corresponds with
important timeout values already present in the kernel. A module
parameter is provided as an emergency override and represents the
default Linux policy for all devices.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
[djbw: add modparam, drop check_device_status()]
Co-developed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/164367306565.208548.1932299464604450843.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The 'struct cxl_mem' object actually represents the state of a CXL
device within the driver. Comments indicating that 'struct cxl_mem' is a
device itself are incorrect. It is data layered on top of a CXL Memory
Expander class device. Rename it 'struct cxl_dev_state'. The 'struct'
cxl_memdev' structure represents a Linux CXL memory device object, and
it uses services and information provided by 'struct cxl_dev_state'.
Update the structure name, function names, and the kdocs to reflect the
real uses of this structure.
Some helper functions that were previously prefixed "cxl_mem_" are
renamed to just "cxl_".
Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20211102202901.3675568-3-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for moving parts of register mapping to cxl_core, split
cxl_pci_setup_regs() into a helper that finds register blocks,
(cxl_find_regblock()), and a generic wrapper that probes the precise
register sets within a block (cxl_setup_regs()).
Move the actual mapping (cxl_map_regs()) of the only register-set that
cxl_pci cares about (memory device registers) up a level from the former
cxl_pci_setup_regs() into cxl_pci_probe().
With this change the unused component registers are no longer mapped,
but the helpers are primed to move into the core.
[djbw: drop cxl_map_regs() for component registers]
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
[djbw: rebase on the cxl_register_map refactor]
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163434053788.914258.18412599112859205220.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In addition to carrying @barno, @block_offset, and @reg_type, add @base
to keep all map/unmap parameters in one object. The helpers
cxl_{map,unmap}_regblock() handle adjusting @base to the @block_offset
at map and unmap time.
Document that @base incorporates @block_offset so that downstream
consumers of a mapped cxl_register_map instance do not need perform any
fixups / can use @base directly.
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163433497228.889435.11271988238496181536.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The structure exists to pass around information about register mapping.
Use it for passing @barno and @block_offset, and eliminate duplicate
local variables.
The helpers that use @map do not care about @cxlm, so just pass them a
pdev instead.
[djbw: reorder before cxl_pci_setup_regs() refactor to improver readability]
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
[djbw: separate @base conversion]
Link: https://lore.kernel.org/r/163416901172.806743.10056306321247850914.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Quoting Dan, "... the request + release regions should probably just be
dropped. It's not like any of the register enumeration would collide
with someone else who already has the registers mapped. The collision
only comes when the registers are mapped for their final usage, and that
will have more precision in the request."
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/163379785872.692348.8981679111988251260.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
cxl_pci_map_regblock() may return an ERR_PTR(), but cxl_pci_setup_regs()
is only prepared for NULL as the error case. Pick the minimal fix for
-stable backport purposes and just have cxl_pci_map_regblock() return
NULL for errors.
Fixes: f8a7e8c29b ("cxl/pci: Reserve all device regions at once")
Cc: <stable@vger.kernel.org>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163433325724.834522.17809774578178224149.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
While interesting to driver developers, the dev_dbg message doesn't do
much except clutter up logs. This information should be attainable
through sysfs, and someday lspci like utilities. This change
additionally helps reduce the LOC in a subsequent patch to refactor some
of cxl_pci register mapping.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/163379784717.692348.3478221381958300790.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Commit 21e9f76733 ("cxl: Rename mem to pci") introduced the cxl_pci
driver which had formerly been named cxl_mem. At the time, the goal was
to be as light touch as possible because there were other patches in
flight. Since things have settled now, and a new cxl_mem driver will be
introduced shortly, spend the LOC now to clean up the existing names.
While here, fix the kernel docs to explain the situation better after
the core rework that has already landed.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/20210913163324.1008564-4-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that the internals of mailbox operations are abstracted from the PCI
specifics a bulk of infrastructure can move to the core.
The CXL_PMEM driver intends to proxy LIBNVDIMM UAPI and driver requests
to the equivalent functionality provided by the CXL hardware mailbox
interface. In support of that intent move the mailbox implementation to
a shared location for the CXL_PCI driver native IOCTL path and CXL_PMEM
nvdimm command proxy path to share.
A unit test framework seeks to implement a unit test backend transport
for mailbox commands to communicate mocked up payloads. It can reuse all
of the mailbox infrastructure minus the PCI specifics, so that also gets
moved to the core.
Finally with the mailbox infrastructure and ioctl handling being
transport generic there is no longer any need to pass file
file_operations to devm_cxl_add_memdev(). That allows all the ioctl
boilerplate to move into the core for unit test reuse.
No functional change intended, just code movement.
Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163116435233.2460985.16197340449713287180.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Commit 3d135db510 ("cxl/core: Move memdev management to core") left
this straggling include for cxl_memdev setup. Clean it up.
Cc: Ben Widawsky <ben.widawsky@intel.com>
Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/163116434668.2460985.12264757586266849616.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for implementing a unit test backend transport for ioctl
operations, and making the mailbox available to the cxl/pmem
infrastructure, move the existing PCI specific portion of mailbox handling
to an "mbox_send" operation.
With this split all the PCI-specific transport details are comprehended
by a single operation and the rest of the mailbox infrastructure is
'struct cxl_mem' and 'struct cxl_memdev' generic.
Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/163116434098.2460985.9004760022659400540.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Commit 0b9159d0ff ("cxl/pci: Store memory capacity values") missed
updating the kernel-doc for 'struct cxl_mem' leading to the following
warnings:
./scripts/kernel-doc -v drivers/cxl/cxlmem.h 2>&1 | grep warn
drivers/cxl/cxlmem.h:107: warning: Function parameter or member 'total_bytes' not described in 'cxl_mem'
drivers/cxl/cxlmem.h:107: warning: Function parameter or member 'volatile_only_bytes' not described in 'cxl_mem'
drivers/cxl/cxlmem.h:107: warning: Function parameter or member 'persistent_only_bytes' not described in 'cxl_mem'
drivers/cxl/cxlmem.h:107: warning: Function parameter or member 'partition_align_bytes' not described in 'cxl_mem'
drivers/cxl/cxlmem.h:107: warning: Function parameter or member 'active_volatile_bytes' not described in 'cxl_mem'
drivers/cxl/cxlmem.h:107: warning: Function parameter or member 'active_persistent_bytes' not described in 'cxl_mem'
drivers/cxl/cxlmem.h:107: warning: Function parameter or member 'next_volatile_bytes' not described in 'cxl_mem'
drivers/cxl/cxlmem.h:107: warning: Function parameter or member 'next_persistent_bytes' not described in 'cxl_mem'
Also, it is redundant to describe those same parameters in the
kernel-doc for cxl_mem_get_partition_info(). Given the only user of that
routine updates the values in @cxlm, just do that implicitly internal to
the helper.
Cc: Ira Weiny <ira.weiny@intel.com>
Reported-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163157174216.2653013.1277706528753990974.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for adding a unit test provider of a cxl_memdev, convert
the 'struct cxl_mem' driver context to carry a generic device rather
than a pci device.
Note, some dev_dbg() lines needed extra reformatting per clang-format.
This conversion also allows the cxl_mem_create() and
devm_cxl_add_memdev() calling conventions to be simplified. The "host"
for a cxl_memdev, must be the same device for the driver that allocated
@cxlm.
Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/163116432973.2460985.7553504957932024222.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Indicator string for mbox and memdev register set to status
incorrectly in error message.
Cc: <stable@vger.kernel.org>
Fixes: 30af97296f ("cxl/pci: Map registers based on capabilities")
Signed-off-by: Li Qiang (Johnny Li) <johnny.li@montage-tech.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163072205089.2250120.8103605864156687395.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
A proposed rework of security_locked_down() users identified that the
cxl_pci driver was passing the wrong lockdown_reason. Update
cxl_mem_raw_command_allowed() to fail raw command access when raw pci
access is also disabled.
Fixes: 13237183c7 ("cxl/mem: Add a "RAW" send command")
Cc: Ben Widawsky <ben.widawsky@intel.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: <stable@vger.kernel.org>
Cc: Ondrej Mosnacek <omosnace@redhat.com>
Cc: Paul Moore <paul@paul-moore.com>
Link: https://lore.kernel.org/r/163072204525.2250120.16615792476976546735.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
CXL spec defines the volatile DPA range to be 0 to Volatile memory size.
It further defines the persistent DPA range to follow directly after the
end of the Volatile DPA through the persistent memory size. Essentially
Volatile DPA range = [0, Volatile size)
Persistent DPA range = [Volatile size, Volatile size + Persistent size)
Adjust the pmem_range start to reflect this and remote the TODO.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210617221620.1904031-4-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Memory devices may specify volatile only, persistent only, and
partitionable space which when added together result in a total capacity.
If Identify Memory Device.Partition Alignment != 0 the device supports
partitionable space. This partitionable space can be split between
volatile and persistent space. The total volatile and persistent sizes
are reported in Get Partition Info. ie
active volatile memory = volatile only + partitionable volatile
active persistent memory = persistent only + partitionable persistent
Define cxl_mem_get_partition(), check for partitionable support, and use
cxl_mem_get_partition() if applicable.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The Identify Memory Device command returns information about the
volatile only and persistent only memory capacities. Store those values
in the cxl_mem structure for later use. While at it, reuse those
calculations to calculate the ram and pmem ranges.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210617221620.1904031-2-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
It is desirable to retain the mappings from the calling function. By
simplifying this code, it will be much more straightforward to do that.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210716231548.174778-3-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In an effort to explicit avoid supporting vendor specific register
blocks (which can happily be mapped from userspace), entirely skip
probing unknown types. The secondary benefit of this will be revealed
in the future with code simplification.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210716231548.174778-2-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The motivation for moving cxl_memdev allocation to the core (beyond
better file organization of sysfs attributes in core/ and drivers in
cxl/), is that device lifetime is longer than module lifetime. The cxl_pci
module should be free to come and go without needing to coordinate with
devices that need the text associated with cxl_memdev_release() to stay
resident. The move fixes a use after free bug when looping driver
load / unload with CONFIG_DEBUG_KOBJECT_RELEASE=y.
Another motivation for disconnecting cxl_memdev creation from cxl_pci is
to enable other drivers, like a unit test driver, to registers memdevs.
Fixes: b39cb1052a ("cxl/mem: Register CXL memX devices")
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162792540495.368511.9748638751088219595.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for moving cxl_memdev allocation to the core, introduce
cdevm_file_operations to coordinate file operations shutdown relative to
driver data release.
The motivation for moving cxl_memdev allocation to the core (beyond
better file organization of sysfs attributes in core/ and drivers in
cxl/), is that device lifetime is longer than module lifetime. The cxl_pci
module should be free to come and go without needing to coordinate with
devices that need the text associated with cxl_memdev_release() to stay
resident. The move will fix a use after free bug when looping driver
load / unload with CONFIG_DEBUG_KOBJECT_RELEASE=y.
Another motivation for passing in file_operations to the core cxl_memdev
creation flow is to allow for alternate drivers, like unit test code, to
define their own ioctl backends.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162792539962.368511.2962268954245340288.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
CXL core is growing, and it's already arguably unmanageable. To support
future growth, move core functionality to a new directory and rename the
file to represent just bus support. Future work will remove non-bus
functionality.
Note that mem.h is renamed to cxlmem.h to avoid a namespace collision
with the global ARCH=um mem.h header.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162792537866.368511.8915631504621088321.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The current naming is confusing and wrong. The Register Locator is
identified by the DSVSEC identifier, not an offset.
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/20210618003009.956929-1-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
While a memX device on /sys/bus/cxl represents a CXL memory expander
control interface, a pmemX device represents the persistent memory
sub-functionality. It bridges the CXL subystem to the libnvdimm nmemX
control interface.
With this skeleton ndctl can now see persistent memory devices on a
"CXL" bus. Later patches add support for translating libnvdimm native
commands to CXL commands.
# ndctl list -BDiu -b CXL
{
"provider":"CXL",
"dev":"ndbus1",
"dimms":[
{
"dev":"nmem1",
"state":"disabled"
},
{
"dev":"nmem0",
"state":"disabled"
}
]
}
Given nvdimm_bus_unregister() removes all devices on an ndbus0 the
cxl_pmem infrastructure needs to arrange ->remove() to be triggered on
cxl_nvdimm devices to keep their enabled state synchronized with the
registration state of their corresponding device on the nvdimm_bus. In
other words, always arrange for cxl_nvdimm_driver.remove() to unregister
nvdimms from an nvdimm_bus ahead of the bus being unregistered.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162380012696.3039556.4293801691038740850.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Some of the commands have already been defined for the support of RAW
commands (to be blocked). Unlike their usage in the RAW interface, when
used through the supported interface, they will be coordinated and
marshalled along with other commands being issued by userspace and the
driver itself. That coordination will be added later.
The list of commands was determined based on the learnings from
libnvdimm and this list is provided directly from Dan.
Recommended-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210413140907.534404-1-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
An HDM decoder is defined in the CXL 2.0 specification as a mechanism
that allow devices and upstream ports to claim memory address ranges and
participate in interleave sets. HDM decoder registers are within the
component register block defined in CXL 2.0 8.2.3 CXL 2.0 Component
Registers as part of the CXL.cache and CXL.mem subregion.
The Component Register Block is found via the Register Locator DVSEC
in a similar fashion to how the CXL Device Register Block is found. The
primary difference is the capability id size of the Component Register
Block is a single DWORD instead of 4 DWORDS.
It's now possible to configure a CXL type 3 device's HDM decoder. Such
programming is expected for CXL devices with persistent memory, and hot
plugged CXL devices that participate in CXL.mem with volatile memory.
Add probe and mapping functions for the component register blocks.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Co-developed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Co-developed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/20210528004922.3980613-6-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Some hardware implementations mix component and device registers into
the same BAR and the driver stack is going to need independent mapping
implementations for those 2 cases. Furthermore, it will be nice to have
finer grained mappings should user space want to map some register
blocks.
Now that individual register blocks are mapped; those blocks regions
should be reserved individually to fully separate the register blocks.
Release the 'global' memory reservation and create individual register
block region reservations through devm.
NOTE: pci_release_mem_regions() is still compatible with
pcim_enable_device() because it removes the automatic region release
when called. So preserve the pcim_enable_device() so that the pcim
interface can be called if needed.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20210604005316.4187340-1-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The information required to map registers based on capabilities is
contained within the bars themselves. This means the bar must be mapped
to read the information needed and then unmapped to map the individual
parts of the BAR based on capabilities.
Change cxl_setup_device_regs() to return a new cxl_register_map, change
the name to cxl_probe_device_regs(). Allocate and place
cxl_register_maps on a list while processing all of the specified
register blocks.
After probing all the register blocks go back and map smaller registers
blocks based on their capabilities and dispose of the cxl_register_maps.
NOTE: pci_iomap() is not managed automatically via pcim_enable_device()
so be careful to call pci_iounmap() correctly.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20210604005036.4187184-1-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In order to remap individual register sets each bar region must be
reserved prior to mapping. Because the details of individual register
sets are contained within the BARs themselves, the bar must be mapped 2
times, once to extract this information and a second time for each
register set.
Rather than attempt to reserve each BAR individually and track if that
bar has been reserved. Open code pcim_iomap_regions() by first
reserving all memory regions on the device and then mapping the bars
individually as needed.
NOTE pci_request_mem_regions() does not need a corresponding
pci_release_mem_regions() because the pci device is managed via
pcim_enable_device().
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20210528004922.3980613-3-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Each register block located in the DVSEC needs to be decoded from 2
words, 'register offset high' and 'register offset low'.
Create a function, cxl_decode_register_block() to perform this decode
and return the bar, offset, and register type of the register block.
Then use the values decoded in cxl_mem_map_regblock() instead of passing
the raw registers.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20210528004922.3980613-2-ira.weiny@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
@cxlm.base only existed to support holding the base found in the
register block mapping code, and pass it along to the register setup
code. Now that the register setup function has all logic around managing
the registers, from DVSEC to iomapping up to populating our CXL specific
information, it is easy to turn the @base values into local variables
and remove them from our device driver state.
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/20210520212953.1181695-1-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Start moving code around to ultimately get rid of @cxlm.base. The
@cxlm.base member serves no purpose other than intermediate storage of
the offset found in cxl_mem_map_regblock() later used by
cxl_mem_setup_regs(). Aside from wanting to get rid of this useless
member, it will help later when adding new register block identifiers.
While @cxlm.base still exists, it will become trivial to remove it in a
future patch.
No functional change is meant to be introduced in this patch.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210407222625.320177-4-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Add a new function specifically for mapping the register blocks and
offsets within. The new function can be used more generically for other
register block identifiers.
No functional change is meant to be introduced in this patch with the
exception of a dev_err printed when the device register block isn't
found.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210407222625.320177-3-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The 'Identify Device' mailbox command returns an 'lsa_size', which is
the size of the label storage area on the device. Export it as a sysfs
attribute so that userspace tooling to read/write the LSA can determine
the size without having to run an 'Identify Device' on their own.
Cc: Ben Widawsky <ben.widawsky@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/20210520194745.1095517-1-vishal.l.verma@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
As the driver has undergone development, it's become clear that the
majority [entirety?] of the current functionality in mem.c is actually a
layer encapsulating functionality exposed through PCI based
interactions. This layer can be used either in isolation or to provide
functionality for higher level functionality.
CXL capabilities exist in a parallel domain to PCIe. CXL devices are
enumerable and controllable via "legacy" PCIe mechanisms; however, their
CXL capabilities are a superset of PCIe. For example, a CXL device may
be connected to a non-CXL capable PCIe root port, and therefore will not
be able to participate in CXL.mem or CXL.cache operations, but can still
be accessed through PCIe mechanisms for CXL.io operations.
To properly represent the PCI nature of this driver, and in preparation for
introducing a new driver for the CXL.mem / HDM decoder (Host-managed Device
Memory) capabilities of a CXL memory expander, rename mem.c to pci.c so that
mem.c is available for this new driver.
The result of the change is that there is a clear layering distinction
in the driver, and a systems administrator may load only the cxl_pci
module and gain access to such operations as, firmware update, offline
provisioning of devices, and error collection. In addition to freeing up
the file name for another purpose, there are two primary reasons this is
useful,
1. Acting upon devices which don't have full CXL capabilities. This
may happen for instance if the CXL device is connected in a CXL
unaware part of the platform topology.
2. Userspace-first provisioning for devices without kernel driver
interference. This may be useful when provisioning a new device
in a specific manner that might otherwise be blocked or prevented
by the real CXL mem driver.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/20210526174413.802913-1-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
