stm32_rtc_valid_alrm function has some issues :
- arithmetical operations are impossible on BCD values
- "cur_mon + 1" can overflow
- the use case with the next month, the same day/hour/minutes went wrong

To solve that, we prefer to use timestamp comparison.
e.g. : On 5 Dec. 2021, the alarm limit is 5 Jan. 2022 (+31 days)
       On 31 Jan 2021, the alarm limit is 28 Feb. 2022 (+28 days)
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-7-valentin.caron@foss.st.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The RTC driver stops the RTCAPB clock during suspend, but the
irq handler from RTC is called before starting clock. Then we are
blocked while accessing RTC registers.

We changes PM callbacks to '_no_irq()' to disable irq during
resume callback and so irq handler will be called after the enable
of RTCAPB clock.
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-6-valentin.caron@foss.st.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Change stm32-rtc driver to not generate an error message when
device probe operation is deferred for a clock.
Signed-off-by: Etienne Carriere <etienne.carriere@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-5-valentin.caron@foss.st.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The rtc is used to update the stgen counter on wake up from
low power modes, so it needs to be as much accurate as possible.

The maximization of asynchronous divider leads to a 4ms rtc
precision clock.
By decreasing pred_a to 0, it will have pred_s=32767 (when
need_accuracy is true), so stgen clock becomes more accurate
with 30us precision.
Nevertheless this will leads to an increase of power consumption.
Signed-off-by: Christophe Guibout <christophe.guibout@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-4-valentin.caron@foss.st.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

RTC counters are stopped when INIT bit in ISR register is set and
start counting from the (eventual) new value when INIT is reset.

In stm32_rtc_init(), called during probe, the INIT bit is set to
program the prescaler and the 24h mode. This halts the RTC counter
at each probe tentative causing the RTC time to loose from 0.3s to
0.8s at each kernel boot.
If the RTC is battery powered, both prescaler value and 24h mode
are kept during power cycle and there is no need to program them
again.

Check if the desired prescaler value and the 24h mode are already
programmed, then skip reprogramming them to avoid halting the time
counter.
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-3-valentin.caron@foss.st.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Date and time are read from two separate RTC registers.
To ensure consistency between the two registers, reading the time
register locks the values in the shadow date register until the
date register is read.
Thus, the whole date/time read requires reading the time register
first, followed by reading the date register.
If the reads are done in reversed order, the shadow date register
will remain locked until a future read operation. The future read
will read the former date value that could be already invalid.

Fix the read order of date/time registers in stm32_rtc_valid_alrm()
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-2-valentin.caron@foss.st.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Add support for new NXP RTC PCF2131.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230622145800.2442116-18-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The PCF2127/29 do NOT support alarms with a 1 second resolution, but
the PCF2131 does.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-17-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The watchdog value register cannot be read on the PCF2131 after being
set.

Add a new flag to identify which variant has read access to this
register, and use this flag to selectively test if watchdog timer was
started by bootloader.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-16-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Introduce in the configuration structure two new values to hold the
watchdog clock source and the min_hw_heartbeat_ms value.

The minimum and maximum timeout values are automatically computed from
the watchdog clock source value for each variant.

The PCF2131 has no 1Hz watchdog clock source, as is the case for
PCF2127/29.

The next best choice is using a 1/4Hz clock, giving a watchdog timeout
range between 4 and 1016s. By using the same register configuration as
for the PCF2127/29, the 1/4Hz clock source is selected.

Note: the PCF2127 datasheet gives a min/max range between 1 and 255s,
but it should be between 2 and 254s, because the watchdog is triggered
when the timer value reaches 1, not 0.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-15-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The sequence for updating the time/date registers is slightly
different between PCF2127/29 and PCF2131.

For PCF2127/29, during write operations, the time counting
circuits (memory locations 03h through 09h) are automatically blocked.

For PCF2131, time/date registers write access requires setting the
STOP bit and sending the clear prescaler instruction (CPR). STOP then
needs to be released once write operation is completed.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-14-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

The PCF2127 and PCF2129 have one output interrupt pin. The PCF2131 has
two, named INT_A and INT_B. The hardware support that any interrupt
source can be routed to either one or both of them.

Force all interrupt sources to go to the INT A pin.

Support to route any interrupt source to INT A/B pins is not supported
by this driver at the moment.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-13-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This RTC is very similar in functionality to the PCF2127/29.

Basically it:
  -supports two new control registers at offsets 4 and 5
  -supports a new reset register (not implemented in this driver)
  -supports 4 tamper detection functions instead of 1
  -has no nvmem (like the PCF2129)
  -has two output interrupt pins

Because of that, most of the register addresses are very different,
although they still follow the same layout. For example, the tamper
registers have a different base address, but the offsets are all the same.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-12-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This will simplify the implementation of new variants into this driver.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-11-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This will simplify the implementation of new variants into this driver.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-10-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This will simplify the implementation of new variants into this driver.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Tested-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-9-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This will simplify the implementation of new variants into this driver.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-8-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

This will simplify the implementation of new variants into this driver.

Some variants (PCF2131) have a 100th seconds register. This register is
currently not supported in this driver.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-7-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Create variant-specific configuration structures to simplify the
implementation of new variants into this driver. It will also avoid
to have too many tests for a specific variant, or a list of variants
for new devices, inside the code itself.

Add configuration options for the support of the NVMEM, bit CD0 in
register WD_CTL as well as the maximum number of registers for each
variant, instead of hardcoding the variant (PCF2127) inside the
i2c_device_id and spi_device_id structures.

Also specify a different maximum number of registers (max_register)
for the PCF2129.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-6-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Noted while reviewing new PCF2131 driver.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-5-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Noted while reviewing new PCF2131 driver.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-4-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Reading the 7 timetamp registers currently involves reading 25 registers
solely to be able to print the content of the three control registers,
in addition to the 7 timestamp registers. This print never occurs,
unless the user enables dynamic debug in this driver or set
CONFIG_RTC_DEBUG.

Reading the timestamp registers should consist of reading 7
consecutive timestamp registers.

This patch optimize the performance of reading the timestamp registers
by reading 7 consecutive registers instead of 25, and dropping the
print of the control registers.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-3-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Improve performance and readability of rtc_read_time() by reading only
the 7 time registers, instead of reading 8 registers (additional CTRL3
register).

We drop reading of CTRL3 to monitor the low battery flag, as this
check is already available in the ioctl. Anyway, this check only
display an info message and has no other impacts.

The code readability also improves as we do not have to fiddle with
buffer pointer and size arithmetic.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-2-hugo@hugovil.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

We just sorted the entries and fields last release, so just out of a
perverse sense of curiosity, I decided to see if we can keep things
ordered for even just one release.

The answer is "No. No we cannot".

I suggest that all kernel developers will need weekly training sessions,
involving a lot of Big Bird and Sesame Street.  And at the yearly
maintainer summit, we will all sing the alphabet song together.

I doubt I will keep doing this.  At some point "perverse sense of
curiosity" turns into just a cold dark place filled with sadness and
despair.

Repeats: 80e62bc8 ("MAINTAINERS: re-sort all entries and fields")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull dma-mapping fixes from Christoph Hellwig:

 - swiotlb area sizing fixes (Petr Tesarik)

* tag 'dma-mapping-6.5-2023-07-09' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: reduce the number of areas to match actual memory pool size
  swiotlb: always set the number of areas before allocating the pool

Pull irq update from Borislav Petkov:

 - Optimize IRQ domain's name assignment

* tag 'irq_urgent_for_v6.5_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqdomain: Use return value of strreplace()

Pull x86 fpu fix from Borislav Petkov:

 - Do FPU AP initialization on Xen PV too which got missed by the recent
   boot reordering work

* tag 'x86_urgent_for_v6.5_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/xen: Fix secondary processors' FPU initialization

Pull x86 fix from Thomas Gleixner:
 "A single fix for the mechanism to park CPUs with an INIT IPI.

  On shutdown or kexec, the kernel tries to park the non-boot CPUs with
  an INIT IPI. But the same code path is also used by the crash utility.
  If the CPU which panics is not the boot CPU then it sends an INIT IPI
  to the boot CPU which resets the machine.

  Prevent this by validating that the CPU which runs the stop mechanism
  is the boot CPU. If not, leave the other CPUs in HLT"

* tag 'x86-core-2023-07-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/smp: Don't send INIT to boot CPU

Pull MIPS fixes from Thomas Bogendoerfer:

 - fixes for KVM

 - fix for loongson build and cpu probing

 - DT fixes

* tag 'mips_6.5_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: kvm: Fix build error with KVM_MIPS_DEBUG_COP0_COUNTERS enabled
  MIPS: dts: add missing space before {
  MIPS: Loongson: Fix build error when make modules_install
  MIPS: KVM: Fix NULL pointer dereference
  MIPS: Loongson: Fix cpu_probe_loongson() again

Pull xfs fix from Darrick Wong:
 "Nothing exciting here, just getting rid of a gcc warning that I got
  tired of seeing when I turn on gcov"

* tag 'xfs-6.5-merge-6' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: fix uninit warning in xfs_growfs_data

Pull more smb client updates from Steve French:

 - fix potential use after free in unmount

 - minor cleanup

 - add worker to cleanup stale directory leases

* tag '6.5-rc-smb3-client-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: Add a laundromat thread for cached directories
  smb: client: remove redundant pointer 'server'
  cifs: fix session state transition to avoid use-after-free issue

Pull NTB updates from Jon Mason:
 "Fixes for pci_clean_master, error handling in driver inits, and
  various other issues/bugs"

* tag 'ntb-6.5' of https://github.com/jonmason/ntb:
  ntb: hw: amd: Fix debugfs_create_dir error checking
  ntb.rst: Fix copy and paste error
  ntb_netdev: Fix module_init problem
  ntb: intel: Remove redundant pci_clear_master
  ntb: epf: Remove redundant pci_clear_master
  ntb_hw_amd: Remove redundant pci_clear_master
  ntb: idt: drop redundant pci_enable_pcie_error_reporting()
  MAINTAINERS: git://github -> https://github.com for jonmason
  NTB: EPF: fix possible memory leak in pci_vntb_probe()
  NTB: ntb_tool: Add check for devm_kcalloc
  NTB: ntb_transport: fix possible memory leak while device_register() fails
  ntb: intel: Fix error handling in intel_ntb_pci_driver_init()
  NTB: amd: Fix error handling in amd_ntb_pci_driver_init()
  ntb: idt: Fix error handling in idt_pci_driver_init()

Lockdep is certainly right to complain about

  (&vma->vm_lock->lock){++++}-{3:3}, at: vma_start_write+0x2d/0x3f
                 but task is already holding lock:
  (&mapping->i_mmap_rwsem){+.+.}-{3:3}, at: mmap_region+0x4dc/0x6db

Invert those to the usual ordering.

Fixes: 33313a74 ("mm: lock newly mapped VMA which can be modified after it becomes visible")
Cc: stable@vger.kernel.org
Signed-off-by: Hugh Dickins <hughd@google.com>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'mm-hotfixes-stable-2023-07-08-10-43' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull hotfixes from Andrew Morton:
 "16 hotfixes. Six are cc:stable and the remainder address post-6.4
  issues"

The merge undoes the disabling of the CONFIG_PER_VMA_LOCK feature, since
it was all hopefully fixed in mainline.

* tag 'mm-hotfixes-stable-2023-07-08-10-43' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  lib: dhry: fix sleeping allocations inside non-preemptable section
  kasan, slub: fix HW_TAGS zeroing with slub_debug
  kasan: fix type cast in memory_is_poisoned_n
  mailmap: add entries for Heiko Stuebner
  mailmap: update manpage link
  bootmem: remove the vmemmap pages from kmemleak in free_bootmem_page
  MAINTAINERS: add linux-next info
  mailmap: add Markus Schneider-Pargmann
  writeback: account the number of pages written back
  mm: call arch_swap_restore() from do_swap_page()
  squashfs: fix cache race with migration
  mm/hugetlb.c: fix a bug within a BUG(): inconsistent pte comparison
  docs: update ocfs2-devel mailing list address
  MAINTAINERS: update ocfs2-devel mailing list address
  mm: disable CONFIG_PER_VMA_LOCK until its fixed
  fork: lock VMAs of the parent process when forking

When forking a child process, the parent write-protects anonymous pages
and COW-shares them with the child being forked using copy_present_pte().

We must not take any concurrent page faults on the source vma's as they
are being processed, as we expect both the vma and the pte's behind it
to be stable.  For example, the anon_vma_fork() expects the parents
vma->anon_vma to not change during the vma copy.

A concurrent page fault on a page newly marked read-only by the page
copy might trigger wp_page_copy() and a anon_vma_prepare(vma) on the
source vma, defeating the anon_vma_clone() that wasn't done because the
parent vma originally didn't have an anon_vma, but we now might end up
copying a pte entry for a page that has one.

Before the per-vma lock based changes, the mmap_lock guaranteed
exclusion with concurrent page faults.  But now we need to do a
vma_start_write() to make sure no concurrent faults happen on this vma
while it is being processed.

This fix can potentially regress some fork-heavy workloads.  Kernel
build time did not show noticeable regression on a 56-core machine while
a stress test mapping 10000 VMAs and forking 5000 times in a tight loop
shows ~5% regression.  If such fork time regression is unacceptable,
disabling CONFIG_PER_VMA_LOCK should restore its performance.  Further
optimizations are possible if this regression proves to be problematic.
Suggested-by: David Hildenbrand <david@redhat.com>
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Closes: https://lore.kernel.org/all/dbdef34c-3a07-5951-e1ae-e9c6e3cdf51b@kernel.org/Reported-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Closes: https://lore.kernel.org/all/b198d649-f4bf-b971-31d0-e8433ec2a34c@applied-asynchrony.com/Reported-by: Jacob Young <jacobly.alt@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217624
Fixes: 0bff0aae ("x86/mm: try VMA lock-based page fault handling first")
Cc: stable@vger.kernel.org
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mmap_region adds a newly created VMA into VMA tree and might modify it
afterwards before dropping the mmap_lock.  This poses a problem for page
faults handled under per-VMA locks because they don't take the mmap_lock
and can stumble on this VMA while it's still being modified.  Currently
this does not pose a problem since post-addition modifications are done
only for file-backed VMAs, which are not handled under per-VMA lock.
However, once support for handling file-backed page faults with per-VMA
locks is added, this will become a race.

Fix this by write-locking the VMA before inserting it into the VMA tree.
Other places where a new VMA is added into VMA tree do not modify it
after the insertion, so do not need the same locking.

Cc: stable@vger.kernel.org
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With recent changes necessitating mmap_lock to be held for write while
expanding a stack, per-VMA locks should follow the same rules and be
write-locked to prevent page faults into the VMA being expanded. Add
the necessary locking.

Cc: stable@vger.kernel.org
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull more SCSI updates from James Bottomley:
 "A few late arriving patches that missed the initial pull request. It's
  mostly bug fixes (the dt-bindings is a fix for the initial pull)"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ufs: core: Remove unused function declaration
  scsi: target: docs: Remove tcm_mod_builder.py
  scsi: target: iblock: Quiet bool conversion warning with pr_preempt use
  scsi: dt-bindings: ufs: qcom: Fix ICE phandle
  scsi: core: Simplify scsi_cdl_check_cmd()
  scsi: isci: Fix comment typo
  scsi: smartpqi: Replace one-element arrays with flexible-array members
  scsi: target: tcmu: Replace strlcpy() with strscpy()
  scsi: ncr53c8xx: Replace strlcpy() with strscpy()
  scsi: lpfc: Fix lpfc_name struct packing

Pull more i2c updates from Wolfram Sang:

 - xiic patch should have been in the original pull but slipped through

 - mpc patch fixes a build regression

 - nomadik cleanup

* tag 'i2c-for-6.5-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: mpc: Drop unused variable
  i2c: nomadik: Remove a useless call in the remove function
  i2c: xiic: Don't try to handle more interrupt events after error