Commit Graph

25 Commits

Author SHA1 Message Date
Sai Prakash Ranjan 8442ef6f11 watchdog: qcom: Move suspend/resume to suspend_late/resume_early
During suspend/resume usecases and tests, it is common to see issues
such as lockups either in suspend path or resume path because of the
bugs in the corresponding device driver pm handling code. In such cases,
it is important that watchdog is active to make sure that we either
receive a watchdog pretimeout notification or a bite causing reset
instead of a hang causing us to hard reset the machine.

There are good reasons as to why we need this because:

* We can have a watchdog pretimeout governor set to panic in which
  case we can have a backtrace which would help identify the issue
  with the particular driver and cause a normal reboot.

* Even in case where there is no pretimeout support, a watchdog
  bite is still useful because some firmware has debug support to dump
  CPU core context on watchdog bite for post-mortem analysis.

* One more usecase which comes to mind is of warm reboot. In case we
  hard reset the target, a cold reboot could be induced resulting in
  lose of ddr contents thereby losing all the debug info.

Currently, the watchdog pm callback just invokes the usual suspend
and resume callback which do not have any special ordering in the
sense that a watchdog can be suspended before the buggy device driver
suspend callback and watchdog resume can happen after the buggy device
driver resume callback. This would mean that the watchdog will not be
active when the buggy driver cause the lockups thereby hanging the
system. So to make sure this doesn't happen, move the watchdog pm to
use late/early system pm callbacks which will ensure that the watchdog
is suspended late and resumed early so that it can catch such issues.

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20210310202004.1436-1-saiprakash.ranjan@codeaurora.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2021-06-21 08:49:12 +02:00
Sai Prakash Ranjan a4f3407c41 watchdog: qcom: Remove incorrect usage of QCOM_WDT_ENABLE_IRQ
As per register documentation, QCOM_WDT_ENABLE_IRQ which is BIT(1)
of watchdog control register is wakeup interrupt enable bit and
not related to bark interrupt at all, BIT(0) is used for that.
So remove incorrect usage of this bit when supporting bark irq for
pre-timeout notification. Currently with this bit set and bark
interrupt specified, pre-timeout notification and/or watchdog
reset/bite does not occur.

Fixes: 36375491a4 ("watchdog: qcom: support pre-timeout when the bark irq is available")
Cc: stable@vger.kernel.org
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20210126150241.10009-1-saiprakash.ranjan@codeaurora.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2021-02-07 14:41:28 +01:00
Manivannan Sadhasivam 7948fab26b watchdog: qcom: Avoid context switch in restart handler
The use of msleep() in the restart handler will cause scheduler to
induce a context switch which is not desirable. This generates below
warning on SDX55 when WDT is the only available restart source:

[   39.800188] reboot: Restarting system
[   39.804115] ------------[ cut here ]------------
[   39.807855] WARNING: CPU: 0 PID: 678 at kernel/rcu/tree_plugin.h:297 rcu_note_context_switch+0x190/0x764
[   39.812538] Modules linked in:
[   39.821954] CPU: 0 PID: 678 Comm: reboot Not tainted 5.10.0-rc1-00063-g33a9990d1d66-dirty #47
[   39.824854] Hardware name: Generic DT based system
[   39.833470] [<c0310fbc>] (unwind_backtrace) from [<c030c544>] (show_stack+0x10/0x14)
[   39.838154] [<c030c544>] (show_stack) from [<c0c218f0>] (dump_stack+0x8c/0xa0)
[   39.846049] [<c0c218f0>] (dump_stack) from [<c0322f80>] (__warn+0xd8/0xf0)
[   39.853058] [<c0322f80>] (__warn) from [<c0c1dc08>] (warn_slowpath_fmt+0x64/0xc8)
[   39.859925] [<c0c1dc08>] (warn_slowpath_fmt) from [<c038b6f4>] (rcu_note_context_switch+0x190/0x764)
[   39.867503] [<c038b6f4>] (rcu_note_context_switch) from [<c0c2aa3c>] (__schedule+0x84/0x640)
[   39.876685] [<c0c2aa3c>] (__schedule) from [<c0c2b050>] (schedule+0x58/0x10c)
[   39.885095] [<c0c2b050>] (schedule) from [<c0c2eed0>] (schedule_timeout+0x1e8/0x3d4)
[   39.892135] [<c0c2eed0>] (schedule_timeout) from [<c039ad40>] (msleep+0x2c/0x38)
[   39.899947] [<c039ad40>] (msleep) from [<c0a59d0c>] (qcom_wdt_restart+0xc4/0xcc)
[   39.907319] [<c0a59d0c>] (qcom_wdt_restart) from [<c0a58290>] (watchdog_restart_notifier+0x18/0x28)
[   39.914715] [<c0a58290>] (watchdog_restart_notifier) from [<c03468e0>] (atomic_notifier_call_chain+0x60/0x84)
[   39.923487] [<c03468e0>] (atomic_notifier_call_chain) from [<c030ae64>] (machine_restart+0x78/0x7c)
[   39.933551] [<c030ae64>] (machine_restart) from [<c0348048>] (__do_sys_reboot+0xdc/0x1e0)
[   39.942397] [<c0348048>] (__do_sys_reboot) from [<c0300060>] (ret_fast_syscall+0x0/0x54)
[   39.950721] Exception stack(0xc3e0bfa8 to 0xc3e0bff0)
[   39.958855] bfa0:                   0001221c bed2fe24 fee1dead 28121969 01234567 00000000
[   39.963832] bfc0: 0001221c bed2fe24 00000003 00000058 000225e0 00000000 00000000 00000000
[   39.971985] bfe0: b6e62560 bed2fc84 00010fd8 b6e62580
[   39.980124] ---[ end trace 3f578288bad866e4 ]---

Hence, replace msleep() with mdelay() to fix this issue.

Fixes: 05e487d905 ("watchdog: qcom: register a restart notifier")
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20201207060005.21293-1-manivannan.sadhasivam@linaro.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2020-12-17 06:46:25 +01:00
Robert Marko 8650d0f9e9 watchdog: qcom_wdt: set WDOG_HW_RUNNING bit when appropriate
If the watchdog hardware is enabled/running during boot, e.g.
due to a boot loader configuring it, we must tell the
watchdog framework about this fact so that it can ping the
watchdog until userspace opens the device and takes over
control.

Do so using the WDOG_HW_RUNNING flag that exists for exactly
that use-case.

Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20201031121115.542752-1-robert.marko@sartura.hr
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2020-12-13 16:17:40 +01:00
Stephen Boyd cc9cc794c3 watchdog: qcom: Use irq flags from firmware
The DT or ACPI tables should tell the driver what the irq flags are.
Given that this driver probes only on DT based platforms and those DT
platforms specify the irq flags we can safely drop the forced irq flag
setting here.

Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Link: https://lore.kernel.org/r/20200220002047.115000-1-swboyd@chromium.org
[groeck: Context conflict resolution]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2020-03-18 11:15:22 +01:00
Ansuel Smith 000de54171 watchdog: qcom-wdt: disable pretimeout on timer platform
Some platform like ipq806x doesn't support pretimeout and define
some interrupts used by qcom,msm-timer. Change the driver to check
and use pretimeout only on qcom,kpss-wdt as it's the only platform
that actually supports it.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200204195648.23350-1-ansuelsmth@gmail.com
[groeck: Conflict resolution]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2020-03-18 11:10:08 +01:00
Sai Prakash Ranjan e0b4f4e0cf watchdog: qcom: Use platform_get_irq_optional() for bark irq
platform_get_irq() prints an error message when the interrupt
is not available. So on platforms where bark interrupt is
not specified, following error message is observed on SDM845.

[    2.975888] qcom_wdt 17980000.watchdog: IRQ index 0 not found

This is also seen on SC7180, SM8150 SoCs as well.
Fix this by using platform_get_irq_optional() instead.

Fixes: 36375491a4 ("watchdog: qcom: support pre-timeout when the bark irq is available")
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20191213064934.4112-1-saiprakash.ranjan@codeaurora.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2020-01-27 15:55:45 +01:00
Jorge Ramirez-Ortiz 52a142140e watchdog: qcom: remove unnecessary variable from private storage
there is no need to continue keeping the clock in private storage.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20190906205411.31666-3-jorge.ramirez-ortiz@linaro.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-09-17 08:59:14 +02:00
Jorge Ramirez-Ortiz 36375491a4 watchdog: qcom: support pre-timeout when the bark irq is available
Use the bark interrupt as the pre-timeout notifier whenever this
interrupt is available.

By default, the pretimeout notification shall occur one second earlier
than the timeout.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20190906205411.31666-2-jorge.ramirez-ortiz@linaro.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-09-17 08:59:14 +02:00
Wolfram Sang ccbf872a3e watchdog: qcom-wdt: drop warning after registering device
The core will print out details now.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-07-08 15:13:13 +02:00
Thomas Gleixner 97fb5e8d9b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 and
  only version 2 as published by the free software foundation this
  program is distributed in the hope that it will be useful but
  without any warranty without even the implied warranty of
  merchantability or fitness for a particular purpose see the gnu
  general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 294 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.825281744@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:36:37 +02:00
Guenter Roeck bba07e6ed7 watchdog: qcom-wdt: Convert to use device managed functions and other improvements
Use device managed functions to simplify error handling, reduce
source code size, improve readability, and reduce the likelyhood of bugs.
Other improvements as listed below.

The conversion was done automatically with coccinelle using the
following semantic patches. The semantic patches and the scripts
used to generate this commit log are available at
https://github.com/groeck/coccinelle-patches

- Drop assignments to otherwise unused variables
- Drop empty remove function
- Use devm_add_action_or_reset() for calls to clk_disable_unprepare
- Introduce local variable 'struct device *dev' and use it instead of
  dereferencing it repeatedly
- Use devm_watchdog_register_driver() to register watchdog device

Cc: Andy Gross <andy.gross@linaro.org>
Cc: David Brown <david.brown@linaro.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-05-05 21:02:26 +02:00
Sai Prakash Ranjan 671cdde36e watchdog: qcom: Add suspend/resume support
This adds the support for qcom watchdog suspend and resume
when entering and exiting deep sleep states. Otherwise
having watchdog active after suspend would result in unwanted
crashes/resets if resume happens after a long time.

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-02-02 14:06:36 +01:00
Fabio Estevam 15210ad18f watchdog: qcom: Check for platform_get_resource() failure
platform_get_resource() may fail, so we should better check its
return value and propagate an error in case it fails.

This avoids a NULL pointer dereference a bit later in the code.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2017-09-09 20:50:35 +02:00
Christian Lamparter f06f35c66f watchdog: qcom: fix kernel panic due to external abort on non-linefetch
This patch fixes a off-by-one in the "watchdog: qcom: add option for
standalone watchdog not in timer block" patch that causes the
following panic on boot:

> Unhandled fault: external abort on non-linefetch (0x1008) at 0xc8874002
> pgd = c0204000
> [c8874002] *pgd=87806811, *pte=0b017653, *ppte=0b017453
> Internal error: : 1008 [#1] SMP ARM
> CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.8.6 #0
> Hardware name: Generic DT based system
> PC is at 0xc02222f4
> LR is at 0x1
> pc : [<c02222f4>]    lr : [<00000001>]    psr: 00000113
> sp : c782fc98  ip : 00000003  fp : 00000000
> r10: 00000004  r9 : c782e000  r8 : c04ab98c
> r7 : 00000001  r6 : c8874002  r5 : c782fe00  r4 : 00000002
> r3 : 00000000  r2 : c782fe00  r1 : 00100000  r0 : c8874002
> Flags: nzcv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
> Control: 10c5387d  Table: 8020406a  DAC: 00000051
> Process swapper/0 (pid: 1, stack limit = 0xc782e210)
> Stack: (0xc782fc98 to 0xc7830000)
> [...]

The WDT_STS (status) needs to be translated via wdt_addr as well.

fixes: f0d9d0f4b4 ("watchdog: qcom: add option for standalone watchdog not in timer block")
Cc: stable@vger.kernel.org # 4.8
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-12-16 06:53:54 -08:00
Matthew McClintock 10073a205d watchdog: qcom: configure BARK time in addition to BITE time
For certain parts and some versions of TZ, TZ will reset the chip
when a BARK is triggered even though it was not configured here. So
by default let's configure this BARK time as well.

Signed-off-by: Matthew McClintock <mmcclint@codeaurora.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Pedersen <twp@codeaurora.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-07-17 21:03:14 +02:00
Matthew McClintock f0d9d0f4b4 watchdog: qcom: add option for standalone watchdog not in timer block
Commit 0dfd582e02 ("watchdog: qcom: use timer devicetree
binding") moved to use the watchdog as a subset timer
register block. Some devices have the watchdog completely
standalone with slightly different register offsets as
well so let's account for the differences here.

The existing "kpss-standalone" compatible string doesn't
make it entirely clear exactly what the device is so
rename to "kpss-wdt" to reflect watchdog timer
functionality. Also update ipq4019 DTS with an SoC
specific compatible.

Signed-off-by: Matthew McClintock <mmcclint@codeaurora.org>
Signed-off-by: Thomas Pedersen <twp@codeaurora.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-07-17 21:03:08 +02:00
Guenter Roeck b6ef36d2c1 watchdog: qcom: Report reboot reason
The Qualcom watchdog timer block reports if the system was reset by the
watchdog. Pass the information to user space.

Reviewed-by: Grant Grundler <grundler@chromium.org>
Tested-by: Grant Grundler <grundler@chromium.org>
Signed-off-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-05-14 09:08:01 +02:00
Guenter Roeck 4d8b229d5e watchdog: Add 'action' and 'data' parameters to restart handler callback
The 'action' (or restart mode) and data parameters may be used by restart
handlers, so they should be passed to the restart callback functions.

Cc: Sylvain Lemieux <slemieux@tycoint.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2016-03-01 15:36:35 +01:00
Guenter Roeck 0933b453f1 watchdog: qcom-wdt: Do not set 'dev' in struct watchdog_device
The 'dev' pointer in struct watchdog_device is set by the watchdog core
when registering the watchdog device and not by the driver. It points to
the watchdog device, not its parent.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-12-28 23:04:08 +01:00
Damien Riegel 80969a68ff watchdog: qcom-wdt: use core restart handler
Get rid of the custom restart handler by using the one provided by the
watchdog core.

Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-12-13 15:29:54 +01:00
Pratyush Anand 6551881c86 Watchdog: Fix parent of watchdog_devices
/sys/class/watchdog/watchdogn/device/modalias can help to identify the
driver/module for a given watchdog node. However, many wdt devices do not
set their parent and so, we do not see an entry for device in sysfs for
such devices.

This patch fixes parent of watchdog_device so that
/sys/class/watchdog/watchdogn/device is populated.

Exceptions: booke, diag288, octeon, softdog and w83627hf -- They do not
have any parent. Not sure, how we can identify driver for these devices.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Maxime Coquelin <maxime.coquelin@st.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-09-09 21:39:22 +02:00
Mathieu Olivari 0dfd582e02 watchdog: qcom: use timer devicetree binding
MSM watchdog configuration happens in the same register block as the
timer, so we'll use the same binding as the existing timer.

The qcom-wdt will now be probed when devicetree has an entry compatible
with "qcom,kpss-timer" or "qcom-scss-timer".

Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2015-04-22 15:27:47 +02:00
Josh Cartwright 05e487d905 watchdog: qcom: register a restart notifier
The WDT's BITE_TIME warm-reset behavior can be leveraged as a last
resort mechanism for triggering chip reset.  Usually, other restart
methods (such as PS_HOLD) are preferrable for issuing a more complete
reset of the chip.  As such, keep the priority of the watchdog notifier
low.

Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-10-20 21:04:19 +02:00
Josh Cartwright 1094ebe9d1 watchdog: qcom: add support for KPSS WDT
Add a driver for the watchdog timer block found in the Krait Processor
Subsystem (KPSS) on the MSM8960, APQ8064, and IPQ8064.

Signed-off-by: Josh Cartwright <joshc@codeaurora.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
2014-10-20 20:52:50 +02:00