Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct cxl_cxims_data.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jonathan Cameron <jonathan.cameron@huawei.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linux-cxl@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230922175319.work.096-kees@kernel.org
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The cxl_test unit test environment models a CXL topology for
sysfs/user-ABI regression testing. It uses interface mocking via the
"--wrap=" linker option to redirect cxl_core routines that parse
hardware registers with versions that just publish objects, like
devm_cxl_enumerate_decoders().
Starting with:
Commit 19ab69a60e ("cxl/port: Store the port's Component Register mappings in struct cxl_port")
...port register enumeration is moved into devm_cxl_add_port(). This
conflicts with the "cxl_test avoids emulating registers stance" so
either the port code needs to be refactored (too violent), or modified
so that register enumeration is skipped on "fake" cxl_test ports
(annoying, but straightforward).
This conflict has happened previously and the "check for platform
device" workaround to avoid instrusive refactoring was deployed in those
scenarios. In general, refactoring should only benefit production code,
test code needs to remain minimally instrusive to the greatest extent
possible.
This was missed previously because it may sometimes just cause warning
messages to be emitted, but it can also cause test failures. The
backport to -stable is only nice to have for clean cxl_test runs.
Fixes: 19ab69a60e ("cxl/port: Store the port's Component Register mappings in struct cxl_port")
Cc: stable@vger.kernel.org
Reported-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/169476525052.1013896.6235102957693675187.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In cxl_port_setup_targets() the region driver validates the
configuration of auto-discovered region decoders, as well
as decoders the driver is preparing to program.
The existing calculations use the encoded interleave granularity
value to create an interleave granularity that properly fans out
when routing an x1 interleave to a greater than x1 interleave.
That all worked well, until this config came along:
Host Bridge: 2 way at 256 granularity
Switch Decoder_A: 1 way at 512
Endpoint_X: 2 way at 256
Switch Decoder_B: 1 way at 512
Endpoint_Y: 2 way at 256
When the Host Bridge interleave is greater than 1 and the root
decoder interleave is exactly 1, the region driver needs to
consider the number of targets in the region when calculating
the expected granularity.
While examining the existing logic, and trying to cover the case
above, a couple of simplifications appeared, hence this proposed
refactoring.
The first simplification is to apply the logic to the nominal
values and use the existing helper function granularity_to_eig() to
translate the desired granularity to the encoded form. This means
the comment and code regarding setting address bits is discarded.
Although that logic is not wrong, it adds a level of complexity that
is not required in the granularity selection. The eig and eiw are
indeed part of the routing instructions programmed into the decoders.
Up-level the discussion to nominal ways and granularity for clearer
analysis.
The second simplification reduces the logic to a single granularity
calculation that works for all cases. The new calculation doesn't
care if parent_iw => 1 because parent_iw is used as a multiplier.
The refactor cleans up a useless assignment of eiw made after the
iw is already calculated.
Regression testing included an examination of all of the ways and
granularity selections made during a run of the cxl_test unit tests.
There were no differences in selections before and after this patch.
Fixes: ("27b3f8d13830 cxl/region: Program target lists")
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230822180928.117596-1-alison.schofield@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Currently, when the region driver attaches a region to a port, it
selects the ports next available decoder to program.
With the addition of auto-discovered regions, a port decoder has
already been programmed so grabbing the next available decoder can
be a mismatch when there is more than one region using the port.
The failure appears like this with CXL DEBUG enabled:
[] cxl_core:alloc_region_ref:754: cxl region0: endpoint9: HPA order violation region0:[mem 0x14780000000-0x1478fffffff flags 0x200] vs [mem 0x880000000-0x185fffffff flags 0x200]
[] cxl_core:cxl_port_attach_region:972: cxl region0: endpoint9: failed to allocate region reference
When CXL DEBUG is not enabled, there is no failure message. The region
just never materializes. Users can suspect this issue if they know their
firmware has programmed decoders so that more than one region is using
a port. Note that the problem may appear intermittently, ie not on
every reboot.
Add a matching method for auto-discovered regions that finds a decoder
based on an HPA range. The decoder range must exactly match the region
resource parameter.
Fixes: a32320b71f ("cxl/region: Add region autodiscovery")
Signed-off-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230905211007.256385-1-alison.schofield@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The following debug output was observed while testing CXL
cxl_core:cxl_walk_cel:721: cxl_mock_mem cxl_mem.0: Opcode 0x4300 unsupported by driver
opcode 0x4300 (Get Poison) is supported by the driver and the mock
device supports it. The logic should be checking that the opcode is
both not poison and not security.
Fix the logic to allow poison and security commands.
Fixes: ad64f5952c ("cxl/memdev: Only show sanitize sysfs files when supported")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230903-cxl-cel-fix-v1-1-e260c9467be3@intel.com
[cleanup cxl_walk_cel() to centralized "enabled" checks]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Use pcie_aer_is_native() to determine the native AER ownership as the
usage of host_bride->native_aer does not cover command line override of
AER ownership.
Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Robert Richter <rrichter@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230823234305.27333-4-Smita.KoralahalliChannabasappa@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
cxl_pci fails to unmask CXL protocol errors when CXL memory error reporting
is not granted native control. Given that CXL memory error reporting uses
the event interface and protocol errors use AER, unmask protocol errors
based only on the native AER setting. Without this change end user
deployments will fail to report protocol errors in the case where native
memory error handling is not granted to Linux.
Also, return zero instead of an error code to not block the communication
with the cxl device when in native memory error reporting mode.
Fixes: 248529edc8 ("cxl: add RAS status unmasking for CXL")
Cc: <stable@vger.kernel.org>
Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
Reviewed-by: Robert Richter <rrichter@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230823234305.27333-2-Smita.KoralahalliChannabasappa@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
If the device does not support Sanitize or Secure Erase commands,
hide the respective sysfs interfaces such that the operation can
never be attempted.
In order to be generic, keep track of the enabled security commands
found in the CEL - the driver does not support Security Passthrough.
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20230726051940.3570-4-dave@stgolabs.net
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
... as is the case with all members of struct cxl_memdev_state.
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20230726051940.3570-3-dave@stgolabs.net
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Driver initialization returned success (return 0) even if the
initialization (cxl_decoder_add() or acpi_table_parse_cedt()) failed.
Return the error instead of swallowing it.
Fixes: f4ce1f766f ("cxl/acpi: Convert CFMWS parsing to ACPI sub-table helpers")
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://lore.kernel.org/r/20230714093146.2253438-2-leitao@debian.org
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
KASAN and KFENCE detected an user-after-free in the CXL driver. This
happens in the cxl_decoder_add() fail path. KASAN prints the following
error:
BUG: KASAN: slab-use-after-free in cxl_parse_cfmws (drivers/cxl/acpi.c:299)
This happens in cxl_parse_cfmws(), where put_device() is called,
releasing cxld, which is accessed later.
Use the local variables in the dev_err() instead of pointing to the
released memory. Since the dev_err() is printing a resource, change the open
coded print format to use the %pr format specifier.
Fixes: e50fe01e1f ("cxl/core: Drop ->platform_res attribute for root decoders")
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://lore.kernel.org/r/20230714093146.2253438-1-leitao@debian.org
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
The CXL_FW_CANCEL macro is used with set/test_bit() so it should be a
bit number and not the shifted value. The original code is the
equivalent of using BIT(BIT(0)) so it's 0x2 instead of 0x1. This has
no effect on runtime because it's done consistently and nothing else
was using the 0x2 bit.
Fixes: 9521875bbe ("cxl: add a firmware update mechanism using the sysfs firmware loader")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/a11b0c78-4717-4f4e-90be-f47f300d607c@moroto.mountain
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
When FW_LOADER is disabled, cxl fails to link:
arm-linux-gnueabi-ld: drivers/cxl/core/memdev.o: in function `cxl_memdev_setup_fw_upload':
memdev.c:(.text+0x90e): undefined reference to `firmware_upload_register'
memdev.c:(.text+0x93c): undefined reference to `firmware_upload_unregister'
In order to use the firmware_upload_register() function, both FW_LOADER
and FW_UPLOAD have to be enabled, which is a bit confusing. In addition,
the dependency is on the wrong symbol, as the caller is part of the
cxl_core.ko module, not the cxl_mem.ko module.
Fixes: 9521875bbe ("cxl: add a firmware update mechanism using the sysfs firmware loader")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20230703112928.332321-1-arnd@kernel.org
Reviewed-by: Xiao Yang <yangx.jy@fujitsu.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Fix a merge error that updated the argument to cxl_mem_get_fw_info() but
not the kernel-doc.
drivers/cxl/core/memdev.c:678: warning: Function parameter or member
'mds' not described in 'cxl_mem_get_fw_info'
drivers/cxl/core/memdev.c:678: warning: Excess function parameter
'cxlds' description in 'cxl_mem_get_fw_info'
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230629021118.102744-1-yang.lee@linux.alibaba.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pick up the first half of the RCH error handling series. The back half
needs some fixups for test regressions. Small conflicts with the PMU
work around register enumeration and setup helpers.
Pick up initial support for the CXL 3.0 performance monitoring
definition. Small conflicts with the firmware update work as they both
placed their init code in the same location.
CXL rev 3.0 introduces a standard performance monitoring hardware
block to CXL. Instances are discovered using CXL Register Locator DVSEC
entries. Each CXL component may have multiple PMUs.
This initial driver supports a subset of types of counter.
It supports counters that are either fixed or configurable, but requires
that they support the ability to freeze and write value whilst frozen.
Development done with QEMU model which will be posted shortly.
Example:
$ perf stat -a -e cxl_pmu_mem0.0/h2d_req_snpcur/ -e cxl_pmu_mem0.0/h2d_req_snpdata/ -e cxl_pmu_mem0.0/clock_ticks/ sleep 1
Performance counter stats for 'system wide':
96,757,023,244,321 cxl_pmu_mem0.0/h2d_req_snpcur/
96,757,023,244,365 cxl_pmu_mem0.0/h2d_req_snpdata/
193,514,046,488,653 cxl_pmu_mem0.0/clock_ticks/
1.090539600 seconds time elapsed
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230526095824.16336-5-Jonathan.Cameron@huawei.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pick up the recent fixes to how CPU caches are managed relative to
region setup / teardown, and make sure that all decoders transition
successfully before updating the region state from COMMIT => ACTIVE.
Pick up the driver cleanups identified in preparation for CXL "type-2"
(accelerator) device support. The major change here from a conflict
generation perspective is the split of 'struct cxl_memdev_state' from
the core 'struct cxl_dev_state'. Since an accelerator may not care about
all the optional features that are standard on a CXL "type-3" (host-only
memory expander) device.
A silent conflict also occurs with the move of the endpoint port to be a
formal property of a 'struct cxl_memdev' rather than drvdata.
Add the first typical (non-sanitization) consumer of the new background
command infrastructure, firmware update. Given both firmware-update and
sanitization were developed in parallel from the common
background-command baseline, resolve some minor context conflicts.
Pick up the sanitization work and the infrastructure for other
background commands for 6.5. Sanitization has a different completion
path than typical background commands so it was important to have both
thought out and implemented before either went upstream.
The sysfs based firmware loader mechanism was created to easily allow
userspace to upload firmware images to FPGA cards. This also happens to
be pretty suitable to create a user-initiated but kernel-controlled
firmware update mechanism for CXL devices, using the CXL specified
mailbox commands.
Since firmware update commands can be long-running, and can be processed
in the background by the endpoint device, it is desirable to have the
ability to chunk the firmware transfer down to smaller pieces, so that
one operation does not monopolize the mailbox, locking out any other
long running background commands entirely - e.g. security commands like
'sanitize' or poison scanning operations.
The firmware loader mechanism allows a natural way to perform this
chunking, as after each mailbox command, that is restricted to the
maximum mailbox payload size, the cxl memdev driver relinquishes control
back to the fw_loader system and awaits the next chunk of data to
transfer. This opens opportunities for other background commands to
access the mailbox and send their own slices of background commands.
Add the necessary helpers and state tracking to be able to perform the
'Get FW Info', 'Transfer FW', and 'Activate FW' mailbox commands as
described in the CXL spec. Wire these up to the firmware loader
callbacks, and register with that system to create the memX/firmware/
sysfs ABI.
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Cc: Russ Weight <russell.h.weight@intel.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Ben Widawsky <bwidawsk@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/20230602-vv-fw_update-v4-1-c6265bd7343b@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Implement support for the non-pmem exclusive secure erase, per
CXL specs. Create a write-only 'security/erase' sysfs file to
perform the requested operation.
As with the sanitation this requires the device being offline
and thus no active HPA-DPA decoding.
The expectation is that userspace can use it such as:
cxl disable-memdev memX
echo 1 > /sys/bus/cxl/devices/memX/security/erase
cxl enable-memdev memX
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20230612181038.14421-7-dave@stgolabs.net
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Implement support for CXL 3.0 8.2.9.8.5.1 Sanitize. This is done by
adding a security/sanitize' memdev sysfs file to trigger the operation
and extend the status file to make it poll(2)-capable for completion.
Unlike all other background commands, this is the only operation that
is special and monopolizes the device for long periods of time.
In addition to the traditional pmem security requirements, all regions
must also be offline in order to perform the operation. This permits
avoiding explicit global CPU cache management, relying instead on the
implict cache management when a region transitions between
CXL_CONFIG_ACTIVE and CXL_CONFIG_COMMIT.
The expectation is that userspace can use it such as:
cxl disable-memdev memX
echo 1 > /sys/bus/cxl/devices/memX/security/sanitize
cxl wait-sanitize memX
cxl enable-memdev memX
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20230612181038.14421-5-dave@stgolabs.net
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Sanitization is by definition a device-monopolizing operation, and thus
the timeslicing rules for other background commands do not apply.
As such handle this special case asynchronously and return immediately.
Subsequent changes will allow completion to be pollable from userspace
via a sysfs file interface.
For devices that don't support interrupts for notifying background
command completion, self-poll with the caveat that the poller can
be out of sync with the ready hardware, and therefore care must be
taken to not allow any new commands to go through until the poller
sees the hw completion. The poller takes the mbox_mutex to stabilize
the flagging, minimizing any runtime overhead in the send path to
check for 'sanitize_tmo' for uncommon poll scenarios.
The irq case is much simpler as hardware will serialize/error
appropriately.
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230612181038.14421-4-dave@stgolabs.net
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Add a read-only sysfs file to display the security state
of a device (currently only pmem):
/sys/bus/cxl/devices/memX/security/state
This introduces a cxl_security_state structure that is
to be the placeholder for common CXL security features.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230612181038.14421-3-dave@stgolabs.net
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
For cases when the mailbox background operation is not complete,
do not "handle" the interrupt, as it was not from this device.
And furthermore there are no racy scenarios such as the hw being
out of sync with the driver and starting a new background op
behind its back.
Reported-by: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Fixes: ccadf1310f (cxl/mbox: Add background cmd handling machinery)
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230612181038.14421-2-dave@stgolabs.net
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
commit eb0764b822 ("cxl/port: Enable the HDM decoder capability for switch ports")
...was added on the observation of CXL memory not being accessible after
setting up a region on a "cold-plugged" device. A "cold-plugged" CXL
device is one that was not present at boot, so platform-firmware/BIOS
has no chance to set it up.
While it is true that the debug found the enable bit clear in the
host-bridge's instance of the global control register (CXL 3.0
8.2.4.19.2 CXL HDM Decoder Global Control Register), that bit is
described as:
"This bit is only applicable to CXL.mem devices and shall
return 0 on CXL Host Bridges and Upstream Switch Ports."
So it is meant to be zero, and further testing confirmed that this "fix"
had no effect on the failure. Revert it, and be more vigilant about
proposed fixes in the future. Since the original copied stable@, flag
this revert for stable@ as well.
Cc: <stable@vger.kernel.org>
Fixes: eb0764b822 ("cxl/port: Enable the HDM decoder capability for switch ports")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168685882012.3475336.16733084892658264991.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Move the endpoint port that the cxl_mem driver establishes from drvdata
to a first class attribute. This is in preparation for device-memory
drivers reusing the CXL core for memory region management. Those drivers
need a type-safe method to retrieve their CXL port linkage. Leave
drvdata for private usage of the cxl_mem driver not external consumers
of a 'struct cxl_memdev' object.
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168679264292.3436160.3901392135863405807.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The current check for 256B Flit mode is incomplete and unnecessary. It
is incomplete because it fails to consider the link speed, or check for
CXL link capabilities. It is unnecessary because unconditionally
unmasking 256B Flit errors is a nop when 256B Flit operation is not
available.
Remove this check in preparation for creating a cxl_probe_link() helper
to centralize this detection.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168679263124.3436160.6228910132469454346.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Switch-level (mid-level) decoders between the platform root and an
endpoint can dynamically switch modes between HDM-H and HDM-D[B]
depending on which region they target. Use the region type to fixup each
decoder that gets allocated to map the given region.
Note that endpoint decoders are meant to determine the region type, so
warn if those ever need to be fixed up, but since it is possible to
continue do so.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168679262543.3436160.13053831955768440312.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for device-memory region creation, arrange for decoders
of CXL_DEVTYPE_DEVMEM memdevs to default to CXL_DECODER_DEVMEM for their
target type.
Revisit this if a device ever shows up that wants to offer mixed HDM-H
(Host-Only Memory) and HDM-DB support, or an CXL_DEVTYPE_DEVMEM device
that supports HDM-H.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168679261945.3436160.11673393474107374595.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for support for HDM-D and HDM-DB configuration
(device-memory, and device-memory with back-invalidate). Rename the current
type designators to use HOSTONLYMEM and DEVMEM as a suffix.
HDM-DB can be supported by devices that are not accelerators, so DEVMEM is
a more generic term for that case.
Fixup one location where this type value was open coded.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168679261369.3436160.7042443847605280593.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In support of the Linux CXL core scaling for a wider set of CXL devices,
allow for the creation of memdevs with some memory device capabilities
disabled. Specifically, allow for CXL devices outside of those claiming
to be compliant with the generic CXL memory device class code, like
vendor specific Type-2/3 devices that host CXL.mem. This implies, allow
for the creation of memdevs that only support component-registers, not
necessarily memory-device-registers (like mailbox registers). A memdev
derived from a CXL endpoint that does not support generic class code
expectations is tagged "CXL_DEVTYPE_DEVMEM", while a memdev derived from a
class-code compliant endpoint is tagged "CXL_DEVTYPE_CLASSMEM".
The primary assumption of a CXL_DEVTYPE_DEVMEM memdev is that it
optionally may not host a mailbox. Disable the command passthrough ioctl
for memdevs that are not CXL_DEVTYPE_CLASSMEM, and return empty strings
from memdev attributes associated with data retrieved via the
class-device-standard IDENTIFY command. Note that empty strings were
chosen over attribute visibility to maintain compatibility with shipping
versions of cxl-cli that expect those attributes to always be present.
Once cxl-cli has dropped that requirement this workaround can be
deprecated.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168679260782.3436160.7587293613945445365.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
'struct cxl_dev_state' makes too many assumptions about the capabilities
of a CXL device. In particular it assumes a CXL device has a mailbox and
all of the infrastructure and state that comes along with that.
In preparation for supporting accelerator / Type-2 devices that may not
have a mailbox and in general maintain a minimal core context structure,
make mailbox functionality a super-set of 'struct cxl_dev_state' with
'struct cxl_memdev_state'.
With this reorganization it allows for CXL devices that support HDM
decoder mapping, but not other general-expander / Type-3 capabilities,
to only enable that subset without the rest of the mailbox
infrastructure coming along for the ride.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168679260240.3436160.15520641540463704524.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
After Jonathan noticed [1] that 'struct cxl_dev_state' had a kernel-doc
entry without a corresponding struct attribute I ran the kernel-doc
script to see what else might be broken. Fix these warnings:
drivers/cxl/cxlmem.h:199: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Event Interrupt Policy
drivers/cxl/cxlmem.h:224: warning: Function parameter or member 'buf' not described in 'cxl_event_state'
drivers/cxl/cxlmem.h:224: warning: Function parameter or member 'log_lock' not described in 'cxl_event_state'
Note that scripts/kernel-doc only finds missing kernel-doc entries. It
does not warn on too many kernel-doc entries, i.e. it did not catch the
fact that @info refers to a not present member.
Link: http://lore.kernel.org/r/20230606121054.000069e1@Huawei.com [1]
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168679259170.3436160.3686460404739136336.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The @map parameter to cxl_probe_X_registers() is filled in with the
mapping parameters of the register block. The @map parameter to
cxl_map_X_registers() only reads that information to perform the
mapping. Mark @map const for cxl_map_X_registers() to clarify that it is
only an input to those helpers.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168679258103.3436160.4941603739448763855.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Jonathan reports that failed attempts to reset a region (teardown its
HDM decoder configuration) mistakenly advance the state of the region
to "not committed". Revert to the previous state of the region on reset
failure so that the reset can be re-attempted.
Reported-by: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Closes: http://lore.kernel.org/r/20230316171441.0000205b@Huawei.com
Fixes: 176baefb2e ("cxl/hdm: Commit decoder state to hardware")
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168696507968.3590522.14484000711718573626.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
cxl_region_decode_reset() walks all the decoders associated with a given
region and disables them. Due to decoder ordering rules it is possible
that a switch in the topology notices that a given decoder can not be
shutdown before another region with a higher HPA is shutdown first. That
can leave the region in a partially committed state.
Capture that state in a new CXL_REGION_F_NEEDS_RESET flag and require
that a successful cxl_region_decode_reset() attempt must be completed
before cxl_region_probe() accepts the region.
This is a corollary for the bug that Jonathan identified in "CXL/region
: commit reset of out of order region appears to succeed." [1].
Cc: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Link: http://lore.kernel.org/r/20230316171441.0000205b@Huawei.com [1]
Fixes: 176baefb2e ("cxl/hdm: Commit decoder state to hardware")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168696507423.3590522.16254212607926684429.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Vikram raised a concern with the theoretical case of a CPU sending
MemClnEvict to a device that is not prepared to receive. MemClnEvict is
a message that is sent after a CPU has taken ownership of a cacheline
from accelerator memory (HDM-DB). In the case of hotplug or HDM decoder
reconfiguration it is possible that the CPU is holding old contents for
a new device that has taken over the physical address range being cached
by the CPU.
To avoid this scenario, invalidate caches prior to tearing down an HDM
decoder configuration.
Now, this poses another problem that it is possible for something to
speculate into that space while the decode configuration is still up, so
to close that gap also invalidate prior to establish new contents behind
a given physical address range.
With this change the cache invalidation is now explicit and need not be
checked in cxl_region_probe(), and that obviates the need for
CXL_REGION_F_INCOHERENT.
Cc: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Fixes: d18bc74ace ("cxl/region: Manage CPU caches relative to DPA invalidation events")
Reported-by: Vikram Sethi <vsethi@nvidia.com>
Closes: http://lore.kernel.org/r/BYAPR12MB33364B5EB908BF7239BB996BBD53A@BYAPR12MB3336.namprd12.prod.outlook.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/168696506886.3590522.4597053660991916591.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Same as for ports, also store the downstream port's Component Register
mappings, use struct cxl_dport for that.
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230622205523.85375-16-terry.bowman@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
CXL capabilities are stored in the Component Registers. To use them,
the specific I/O ranges of the capabilities must be determined by
probing the registers. For this, the whole Component Register range
needs to be mapped temporarily to detect the offset and length of a
capability range.
In order to use more than one capability of a component (e.g. RAS and
HDM) the Component Register are probed and its mappings created
multiple times. This also causes overlapping I/O ranges as the whole
Component Register range must be mapped again while a capability's I/O
range is already mapped.
Different capabilities cannot be setup at the same time. E.g. the RAS
capability must be made available as soon as the PCI driver is bound,
the HDM decoder is setup later during port enumeration. Moreover,
during early setup it is still unknown if a certain capability is
needed. A central capability setup is therefore not possible,
capabilities must be individually enabled once needed during
initialization.
To avoid a duplicate register probe and overlapping I/O mappings, only
probe the Component Registers one time and store the Component
Register mapping in struct port. The stored mappings can be used later
to iomap the capability register range when enabling the capability,
which will be implemented in a follow-on patch.
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230622205523.85375-15-terry.bowman@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
CXL RAS capabilities must be enabled and accessible as soon as the CXL
endpoint is detected in the PCI hierarchy and bound to the cxl_pci
driver. This needs to be independent of other modules such as cxl_port
or cxl_mem.
CXL RAS capabilities reside in the Component Registers. For an RCH
this is determined by probing RCRB which is implemented very late once
the CXL Memory Device is created.
Change this by moving the RCRB probe to the cxl_pci driver. Do this by
using a new introduced function cxl_pci_find_port() similar to
cxl_mem_find_port() to determine the involved dport by the endpoint's
PCI handle. Plug this into the existing cxl_pci_setup_regs() function
to setup Component Registers. Probe the RCRB in case the Component
Registers cannot be located through the CXL Register Locator
capability.
This unifies code and early sets up the Component Registers at the
same time for both, VH and RCH mode. Only the cxl_pci driver is
involved for this. This allows an early mapping of the CXL RAS
capability registers.
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230622205523.85375-14-terry.bowman@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In order to move the RCH dport component register setup to cxl_pci the
base address must be stored in CXL device state (cxlds) for both
modes, RCH and VH. Store it in cxlds->component_reg_phys and use it
for endpoint creation.
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230622205523.85375-13-terry.bowman@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
When probing the Component Registers in function cxl_probe_regs()
there are also checks for the existence of the HDM and RAS
capabilities. The checks may fail for components that do not implement
the HDM capability causing the Component Registers setup to fail too.
Remove the checks for a generalized use of cxl_probe_regs() and check
them directly before mapping the RAS or HDM capabilities. This allows
it to setup other Component Registers esp. of an RCH Downstream Port,
which will be implemented in a follow-on patch.
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230622205523.85375-12-terry.bowman@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The Component Register base address @component_reg_phys is no longer
used after the rework of the Component Register setup which now uses
struct member @comp_map instead. Remove the base address.
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230622205523.85375-11-terry.bowman@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
During a Host Bridge's downstream port enumeration the CHBS entries in
the CEDT table are parsed, its Component Register base address
extracted and then stored in struct cxl_dport. The CHBS may contain
either the RCRB (RCH mode) or the Host Bridge's Component Registers
(CHBCR, VH mode). The RCRB further contains the CXL downstream port
register base address, while in VH mode the CXL Downstream Switch
Ports are visible in the PCI hierarchy and the DP's component regs are
disovered using the CXL DVSEC register locator capability. The
Component Registers derived from the CHBS for both modes are different
and thus also must be treated differently. That is, in RCH mode, the
component regs base should be bound to the dport, but in VH mode to
the CXL host bridge's port object.
The current implementation stores the CHBCR in addition in struct
cxl_dport and copies it later from there to struct cxl_port. As a
result, the dport contains the wrong Component Registers base address
and, e.g. the RAS capability of a CXL Root Port cannot be detected.
To fix the CHBCR binding, attach it directly to the Host Bridge's
@cxl_port structure. Do this during port creation of the Host Bridge
in add_host_bridge_uport(). Factor out CHBS parsing code in
add_host_bridge_dport() and use it in both functions.
Co-developed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230622205523.85375-10-terry.bowman@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Just moving code to reorder functions to later share cxl_get_chbs()
with add_host_bridge_uport().
This makes changes in the next patch visible. No other changes at all.
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230622205523.85375-9-terry.bowman@amd.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
