If there is an issue with the AXI SPI Engine hardware a scheduled
transfer might never be completed and spi_sync() will block forever.
This due to the uninterruptible wait for completion waiting for the
spi_finalize_current_message() that never comes.

Add a watchdog timer that will abort a transfer 5 seconds after it has
been started. This will potentially leave the hardware in a broken state
but it allows software to recover and allow to better diagnose the
underlying issue.
Co-developed-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-9-063672323fce@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

Now that the AXI SPI Engine driver has support for the various CS delays
requested through struct spi_message, we don't need to add a separate
delay to the CS assertion instruction. Otherwise, we end up with longer
than requested delays.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-8-063672323fce@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This modifies the ADI AXI SPI Engine driver to restore the clkdiv
configuration register at the end of a SPI message. Having the clkdiv in
a known state is needed to be able to add a new command in the future
that only performs a delay without any SPI transfers. Furthermore having
that state be the smallest possible divider will allow these delays to
have the highest possible precision.

Changing the initial value of clk_div from -1 to 1 is now possible
because we know the function will always be called with a known clkdiv
config register state. Making this change will also have the effect of
not emitting a clkdiv configuration register instruction in cases where
the maximum sclk rate is used. Having one less instruction to process
reduces delays on the bus which will be beneficial when we implement
offload support to enable reading data from devices at very high rates.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-7-063672323fce@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This adds handling of xfer->cs_change_delay to the AXI SPI Engine
driver.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-6-063672323fce@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This replaces the xfer parameter of spi_engine_gen_sleep() in the AXI
SPI Engine driver with parameters for the delay in nanoseconds and the
SPI SCLK rate. This will allow this function to be used by callers in
the future that do not have a spi_transfer struct.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-5-063672323fce@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This fixes the sleep ticks calculation when generating sleep
instructions in the AXI SPI Engine driver. The previous calculation
was ignoring delays less than one microsecond and missed a microsecond
to second conversion factor.

This fixes the first issue by not rounding to microseconds. Now that
xfer->effective_speed_hz is guaranteed to be set correctly, we can use
that to simplify the calculation. This new calculation replaces the old
incorrect math.

Also add unit suffix to the delay variable for clarity while we are
touching this.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-4-063672323fce@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

Now that host->max_speed_hz and xfer->effective_speed_hz are properly
set, we can use them instead of having to do more complex calculations
to get the clock divider for each transfer.

This removes the spi_engine_get_clk_div() function and replaces it with
just dividing the two clock rates. Since the hardware register value is
the divider minus one, we need to subtract one. Subtracting one was
previously done in the spi_engine_get_clk_div() function.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-3-063672323fce@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This adds a new spi_engine_precompile_message() function to the ADI AXI
SPI Engine driver to populate the xfer->effective_speed_hz field since
the SPI core doesn't/can't do this for us.

This driver is already using spi_delay_to_ns() which depends on
effective_speed_hz to get an accurate value in some cases.
Having an effective_speed_hz value can also be used in future changes
to simplify other code.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-2-063672323fce@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

In the AXI SPI Engine driver, the spi_engine_compile_message() function
does not return any error and none of the callers check the return
value. So we can change the return type to void and drop the return 0.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20231204-axi-spi-engine-series-2-v1-1-063672323fce@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

Use device life-cycle managed register function to simplify probe error
path and eliminate need for explicit remove function.
Signed-off-by: Andrew Davis <afd@ti.com>
Link: https://lore.kernel.org/r/20231117161006.87734-5-afd@ti.comSigned-off-by: Mark Brown <broonie@kernel.org>

Merge series from David Lechner <dlechner@baylibre.com>:

We are working towards adding support for the offload feature[1] of the
AXI SPI Engine IP core. Before we can do that, we want to make some
general fixes and improvements to the driver. In order to avoid a giant
series with 35+ patches, we are splitting this up into a few smaller
series.

This first series mostly doing some housekeeping:
* Convert device tree bindings to yaml.
* Add a MAINTAINERS entry.
* Clean up probe and remove using devm.
* Separate message state from driver state.
* Add support for cs_off and variable word size.

Once this series is applied, we will follow up with a second series of
general improvements, and then finally a 3rd series that implements the
offload support. The offload support will also involve the IIO
subsystem (a new IIO driver will depend on the new SPI offload feature),
so I'm mentioning this now in case we want to do anything ahead of time
to prepare for that (e.g. putting all of these changes on a separate
branch).

[1]: https://wiki.analog.com/resources/fpga/peripherals/spi_engine/offload

The AXI SPI Engine IP supports any word size from 1 to 32 bits. This
adds support for this by setting the bits_per_word_mask and emitting
the appropriate instruction to the SPI Engine each time a transfer
requires a new word size.

The functions that transfer tx/rx buffers from/to the SPI Engine
registers (spi_engine_write_{tx,rx}_fifo()) as well as the function that
creates the transfer instruction (spi_engine_gen_xfer()) also have to be
modified to take into account the word size since xfer->len is the
size of the buffers in bytes rather than words.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-14-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This adds support for the spi_transfer::cs_off flag to the AXI SPI
Engine driver.

The logic is copied from the generic spi_transfer_one_message() in
spi.c.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-13-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

In the AXI SPI Engine driver, the struct spi_engine::msg member was used
to keep track of the current message being processed. The SPI core is
already keeping track of this, so we don't need to duplicate the effort.

In most cases, we already have a pointer to the current message, so we
can pass it directly to the functions that need it. In the one case
where we don't have a pointer to the current message, we can get it
from struct spi_controller::cur_msg.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-12-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

In the AXI SPI Engine driver, the completed_id field in the driver
state is only used in one function and the value does not need to
persist between function calls. Therefore, it can be removed from the
driver state and made a local variable in the function where it is used.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-11-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This modifies the AXI SPI Engine driver to make use of the
message_prepare and message_unprepare callbacks. This separates
the concerns of allocating and freeing the message state from the
transfer_one_message callback.

The main benfit of this is so that future callers of
spi_finalize_current_message() will not have to do manual cleanup
of the state.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-10-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This moves the message state in the AXI SPI Engine driver to a new
struct spi_engine_msg_state.

Previously, the driver state contained various pointers that pointed
to memory owned by a struct spi_message. However, it did not set any of
these pointers to NULL when a message was completed. This could lead to
use after free bugs.

Example of how this could happen:
1. SPI core calls into spi_engine_transfer_one_message() with msg1.
2. Assume something was misconfigured and spi_engine_tx_next() is not
   called enough times in interrupt callbacks for msg1 such that
   spi_engine->tx_xfer is never set to NULL before the msg1 completes.
3. SYNC interrupt is received and spi_finalize_current_message() is
   called for msg1. spi_engine->msg is set to NULL but no other
   message-specific state is reset.
4. Caller that sent msg1 is notified of the completion and frees msg1
   and the associated xfers and tx/rx buffers.
4. SPI core calls into spi_engine_transfer_one_message() with msg2.
5. When spi_engine_tx_next() is called for msg2, spi_engine->tx_xfer is
   still be pointing to an xfer from msg1, which was already freed.
   spi_engine_xfer_next() tries to access xfer->transfer_list of one
   of the freed xfers and we get a segfault or undefined behavior.

To avoid issues like this, instead of putting per-message state in the
driver state struct, we can make use of the struct spi_message::state
field to store a pointer to a new struct spi_engine_msg_state. This way,
all of the state that belongs to specific message stays with that
message and we don't have to remember to manually reset all aspects of
the message state when a message is completed. Rather, a new state is
allocated for each message.

Most of the changes are just renames where the state is accessed. One
place where this wasn't straightforward was the sync_id member. This
has been changed to use ida_alloc_range() since we needed to separate
the per-message sync_id from the per-controller next available sync_id.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-9-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This adds a check for a valid SCLK rate in the axi-spi-engine driver
during probe. A valid rate is required to get accurate timing for delays
and by not allowing 0 we can avoid divide by zero errors later without
additional checks.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-8-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This replaces spi_register_controller() with
devm_spi_register_controller() in the AXI SPI Engine driver. This
saves us from having to call spi_unregister_controller() in the
remove function.

The remove function is also removed since it is no longer needed.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-7-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This replaces request_irq() with devm_request_irq() in the AXI SPI
Engine driver. This simplifies the error path and removes the need to
call free_irq() in the remove function.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-6-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This moves the reset of the hardware to a devm action in the AXI SPI
Engine driver. This will allow us to use devm on later calls in the
probe function while preserving the order during cleanup.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-5-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This modifies the AXI SPI Engine driver to use devm_spi_alloc_host()
instead of spi_alloc_host() to simplify the code a bit.

In addition to simplifying the error paths in the probe function, we
can also remove spi_controller_get/put() calls in the remove function
since devm_spi_alloc_host() sets a flag to no longer decrement the
controller reference count in the spi_unregister_controller() function.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-4-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This simplifies the private data allocation in the AXI SPI Engine driver
by making use of the feature built into the spi_alloc_host() function
instead of doing it manually.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-3-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

The AXI SPI Engine driver has been in the kernel for many years but has
lacked a proper maintainers entry. This adds a new entry for the driver
and the devicetree bindings.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-2-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

This converts the axi-spi-engine binding to yaml.

There are a few minor fixes in the conversion:
* Added maintainers.
* Added descriptions for the clocks.
* Fixed the double "@" in the example.
* Added a comma between the clocks in the example.
Signed-off-by: David Lechner <dlechner@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20231117-axi-spi-engine-series-1-v1-1-cc59db999b87@baylibre.comSigned-off-by: Mark Brown <broonie@kernel.org>

dma_request_slave_channel() is deprecated. dma_request_chan() should
be used directly instead.

Switch to the preferred function and update the error handling accordingly.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/1c88236b5d6bff0af902492ea9e066c8cb0dfef5.1700391566.git.christophe.jaillet@wanadoo.frSigned-off-by: Mark Brown <broonie@kernel.org>

Merge tag 'kbuild-fixes-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Fix section mismatch warning messages for riscv and loongarch

 - Remove CONFIG_IA64 left-over from linux/export-internal.h

 - Fix the location of the quotes for UIMAGE_NAME

 - Fix a memory leak bug in Kconfig

* tag 'kbuild-fixes-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: fix memory leak from range properties
  kbuild: Move the single quotes for image name
  linux/export: clean up the IA-64 KSYM_FUNC macro
  modpost: fix section mismatch message for RELA

Pull irq fix from Borislav Petkov:

 - Flush the translation service tables to prevent unpredictable
   behavior on non-coherent GIC devices

* tag 'irq_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3-its: Flush ITS tables correctly in non-coherent GIC designs

Pull x86 fixes from Borislav Petkov:

 - Ignore invalid x2APIC entries in order to not waste per-CPU data

 - Fix a back-to-back signals handling scenario when shadow stack is in
   use

 - A documentation fix

 - Add Kirill as TDX maintainer

* tag 'x86_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/acpi: Ignore invalid x2APIC entries
  x86/shstk: Delay signal entry SSP write until after user accesses
  x86/Documentation: Indent 'note::' directive for protocol version number note
  MAINTAINERS: Add Intel TDX entry

Pull timer fix from Borislav Petkov:

 - Do the push of pending hrtimers away from a CPU which is being
   offlined earlier in the offlining process in order to prevent a
   deadlock

* tag 'timers_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimers: Push pending hrtimers away from outgoing CPU earlier

Pull scheduler fixes from Borislav Petkov:

 - Fix virtual runtime calculation when recomputing a sched entity's
   weights

 - Fix wrongly rejected unprivileged poll requests to the cgroup psi
   pressure files

 - Make sure the load balancing is done by only one CPU

* tag 'sched_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix the decision for load balance
  sched: psi: fix unprivileged polling against cgroups
  sched/eevdf: Fix vruntime adjustment on reweight

Pull locking fix from Borislav Petkov:

 - Fix a hardcoded futex flags case which lead to one robust futex test
   failure

* tag 'locking_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: Fix hardcoded flags

Pull perf fix from Borislav Petkov:

 - Make sure the context refcount is transferred too when migrating perf
   events

* tag 'perf_urgent_for_v6.7_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Fix cpuctx refcounting

Pull SCSI fixes from James Bottomley:
 "Seven small fixes, six in drivers and one in sd.

  The sd fix is so large because it changes a struct pointer to a struct
  but otherwise is fairly simple"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ufs: qcom-ufs: dt-bindings: Document the SM8650 UFS Controller
  scsi: sd: Fix sshdr use in sd_suspend_common()
  scsi: scsi_debug: Delete some bogus error checking
  scsi: scsi_debug: Fix some bugs in sdebug_error_write()
  scsi: ufs: core: Fix racing issue between ufshcd_mcq_abort() and ISR
  scsi: ufs: core: Expand MCQ queue slot to DeviceQueueDepth + 1
  scsi: qla2xxx: Fix system crash due to bad pointer access

Pull parisc fixes from Helge Deller:
 "On parisc we still sometimes need writeable stacks, e.g. if programs
  aren't compiled with gcc-14. To avoid issues with the upcoming
  systemd-254 we therefore have to disable prctl(PR_SET_MDWE) for now
  (for parisc only).

  The other two patches are minor: a bugfix for the soft power-off on
  qemu with 64-bit kernel and prefer strscpy() over strlcpy():

   - Fix power soft-off on qemu

   - Disable prctl(PR_SET_MDWE) since parisc sometimes still needs
     writeable stacks

   - Use strscpy instead of strlcpy in show_cpuinfo()"

* tag 'parisc-for-6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  prctl: Disable prctl(PR_SET_MDWE) on parisc
  parisc/power: Fix power soft-off when running on qemu
  parisc: Replace strlcpy() with strscpy()

Pull xfs fixes from Chandan Babu:

 - Fix deadlock arising due to intent items in AIL not being cleared
   when log recovery fails

 - Fix stale data exposure bug when remapping COW fork extents to data
   fork

 - Fix deadlock when data device flush fails

 - Fix AGFL minimum size calculation

 - Select DEBUG_FS instead of XFS_DEBUG when XFS_ONLINE_SCRUB_STATS is
   selected

 - Fix corruption of log inode's extent count field when NREXT64 feature
   is enabled

* tag 'xfs-6.7-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: recovery should not clear di_flushiter unconditionally
  xfs: inode recovery does not validate the recovered inode
  xfs: fix again select in kconfig XFS_ONLINE_SCRUB_STATS
  xfs: fix internal error from AGFL exhaustion
  xfs: up(ic_sema) if flushing data device fails
  xfs: only remap the written blocks in xfs_reflink_end_cow_extent
  XFS: Update MAINTAINERS to catch all XFS documentation
  xfs: abort intent items when recovery intents fail
  xfs: factor out xfs_defer_pending_abort

Pull nfsd fixes from Chuck Lever:

 - Fix several long-standing bugs in the duplicate reply cache

 - Fix a memory leak

* tag 'nfsd-6.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  NFSD: Fix checksum mismatches in the duplicate reply cache
  NFSD: Fix "start of NFS reply" pointer passed to nfsd_cache_update()
  NFSD: Update nfsd_cache_append() to use xdr_stream
  nfsd: fix file memleak on client_opens_release

Pull smb client fixes from Steve French:

 - multichannel fixes (including a lock ordering fix and an important
   refcounting fix)

 - spnego fix

* tag '6.7-rc1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix lock ordering while disabling multichannel
  cifs: fix leak of iface for primary channel
  cifs: fix check of rc in function generate_smb3signingkey
  cifs: spnego: add ';' in HOST_KEY_LEN

systemd-254 tries to use prctl(PR_SET_MDWE) for it's MemoryDenyWriteExecute
functionality, but fails on parisc which still needs executable stacks in
certain combinations of gcc/glibc/kernel.

Disable prctl(PR_SET_MDWE) by returning -EINVAL for now on parisc, until
userspace has catched up.
Signed-off-by: Helge Deller <deller@gmx.de>
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Sam James <sam@gentoo.org>
Closes: https://github.com/systemd/systemd/issues/29775Tested-by: Sam James <sam@gentoo.org>
Link: https://lore.kernel.org/all/875y2jro9a.fsf@gentoo.org/
Cc: <stable@vger.kernel.org> # v6.3+