Commit Graph

20 Commits

Author SHA1 Message Date
Jacky Bai
423fc66eb6 wdog: imx7ulp: Enable wdog int_en bit for watchdog any reset
The wdog INT_EN bit in CS register should be set to '1' to trigger
WDOG_ANY external reset on i.MX93.

Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20231010081909.2899101-1-ping.bai@nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2023-10-29 19:45:08 +01:00
Rob Herring
cc85f87a77 watchdog: Explicitly include correct DT includes
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it was merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230726233302.3812749-1-robh@kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2023-08-13 14:29:49 +02:00
Christophe JAILLET
f3a0dd6489 watchdog: imx7ulp: Use devm_clk_get_enabled() helper
The devm_clk_get_enabled() helper:
   - calls devm_clk_get()
   - calls clk_prepare_enable() and registers what is needed in order to
     call clk_disable_unprepare() when needed, as a managed resource.

This simplifies the code and avoids the need of a dedicated function used
with devm_add_action_or_reset().

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/f23a2cf84958adca255b82fd688e7cee0461760f.1672484376.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2023-02-12 15:32:50 +01:00
Alice Guo
8ed2dc4855 watchdog: imx93: add watchdog timer on imx93
The WDOG clocks are sourced from lpo_clk, and lpo_clk is the fixed
32KHz. TOVAL contains the 16-bit value used to set the timeout period of
the watchdog. When the timeout period exceeds 2 seconds, the value
written to the TOVAL register is larger than 16-bit can represent.
Enabling watchdog prescaler can solve this problem.

Two points need to be aware of:
1. watchdog prescaler enables a fixed 256 pre-scaling of watchdog
counter reference clock
2. reconfiguration takes about 55ms on imx93

Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220825083256.14565-8-alice.guo@oss.nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2022-10-02 12:55:47 +02:00
Jason Liu
cef6bc98d5 watchdog: imx7ulp_wdt: init wdog when it was active
Paired with suspend, we can only init wdog again when it was active
and ping it once to avoid the watchdog timeout after it resumed.

Signed-off-by: Jason Liu <jason.hui.liu@nxp.com>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
Reviewed-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Tested-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220825083256.14565-7-alice.guo@oss.nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2022-10-02 12:55:46 +02:00
Ye Li
c32b53f965 watchdog: imx7ulp_wdt: Handle wdog reconfigure failure
Current driver may meet reconfigure failure caused by below reasons:

1. The wdog on iMX7ULP has different behavior after RCS valid. It needs
   to wait more than 2.5 wdog clock for clock sync before next
   reconfiguration, while imx8ulp wdog does not need such delay.

2. After unlock, there is 128 bus clock window opened for reconfiguration,
   but on iMX8ULP, the HW can't guarantee the latency. So it is possible
   the window is closed before the writing arrives to wdog.

3. If the PRES is enabled, the RCS valid time becomes x256 to the time
   of PRES disabled. It is about 1715ms on iMX8ULP. So We have to increase
   the RCS timeout and can't wait it in IRQ disabled.

The patch updates the driver to handle failures

1. Using different wait for unlock and RCS. Unlock valid time is very short
   and only related to bus clock. It must be in IRQ disabled to avoid
   being interrupted in 128 clock window. But for RCS time, it is longer
   and ok for IRQ enabled.

2. Add retry for any reconfigure failure with default 5 times.

3. Add "fsl,imx8ulp-wdt" compatile string for iMX8ULP and afterwards
   platform which don't need more 2.5 wdog clock after RCS valid.
   For imx7ulp, add post delay of 2.5 clock after RCS valid.

Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220825083256.14565-6-alice.guo@oss.nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2022-10-02 12:55:46 +02:00
Ye Li
52c4d05113 watchdog: imx7ulp_wdt: Fix RCS timeout issue
According to measure on i.MX7ULP and i.MX8ULP, the RCS done needs
about 3400us and 6700us respectively. So current 20us timeout is
not enough. When reconfiguring is on-going, unlock and configure CS
will lead to unknown result.

Increase the wait timeout value to 10ms and check the return value
of RCS wait to fix the issue

Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Acked-by: Jason Liu <jason.hui.liu@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220825083256.14565-5-alice.guo@oss.nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2022-10-02 12:55:45 +02:00
Ye Li
e809daec17 watchdog: imx7ulp_wdt: Check CMD32EN in wdog init
When bootloader has enabled the CMD32EN bit, switch to use 32bits
unlock command to unlock the CS register. Using 32bits command will
help on avoiding 16 bus cycle window violation for two 16 bits
commands.

Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Acked-by: Jason Liu <jason.hui.liu@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220825083256.14565-4-alice.guo@oss.nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2022-10-02 12:55:45 +02:00
Jacky Bai
6371593fba watchdog: imx7ulp: Add explict memory barrier for unlock sequence
When reconfiguring the WDOG Timer of i.MX7ULP, there is a certain
probability causes it to reset. The reason is that the CMD32EN of the
WDOG Timer of i.MX7ULP is disabled in bootloader. The unlock sequence
are two 16-bit writes to the CNT register within 16 bus clocks. Adding
mb() is to guarantee that two 16-bit writes are finished within 16 bus
clocks. Memory barriers cannot be added between these two 16-bit writes
so that writel_relaxed is used.

Suggested-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
Reviewed-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220825083256.14565-3-alice.guo@oss.nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2022-10-02 12:55:44 +02:00
Anson Huang
f182683333 watchdog: imx7ulp: Move suspend/resume to noirq phase
The i.MX7ULP's watchdog is enabled by default when out of reset, so the
resume callback which is to disable watchdog should be called earlier
to avoid unexpected timeout, move suspend/resume callback to noirq phase.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Tested-by: Peter Chen <peter.chen@nxp.com>
Tested-by: Li Jun <jun.li@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220825083256.14565-2-alice.guo@oss.nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2022-10-02 12:55:44 +02:00
Anson Huang
0cfbe17959 watchdog: imx7ulp: Watchdog should continue running for wait/stop mode
When kernel idle, system will enter wait/stop mode, wdog should continue
running in this scenario, and the refresh thread can wake up system from
wait/stop mode.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/1596150213-31638-2-git-send-email-Anson.Huang@nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2020-10-14 15:02:26 +02:00
Anson Huang
743949466e watchdog: imx7ulp: Strictly follow the sequence for wdog operations
According to reference manual, the i.MX7ULP WDOG's operations except
refresh should follow below sequence:

1. disable global interrupts;
2. unlock the wdog and wait unlock bit set;
3. reconfigure the wdog and wait for reconfiguration bit set;
4. enabel global interrupts.

Strictly follow the recommended sequence can make it more robust.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/1596150213-31638-1-git-send-email-Anson.Huang@nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2020-10-14 15:02:23 +02:00
Anson Huang
dca96e0117 watchdog: imx7ulp: Remove unused include of init.h
There is nothing in use from init.h, remove it.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Link: https://lore.kernel.org/r/1582250430-8872-2-git-send-email-Anson.Huang@nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2020-03-18 11:15:23 +01:00
Fabio Estevam
91ced83c6e watchdog: imx7ulp: Fix missing conversion of imx7ulp_wdt_enable()
Since commit 747d88a1a8 ("watchdog: imx7ulp: Pass the wdog instance in
imx7ulp_wdt_enable()") imx7ulp_wdt_enable() accepts a watchdog_device
structure, so fix one instance that missed such conversion.

This also fixes the following sparse warning:

drivers/watchdog/imx7ulp_wdt.c:115:31: warning: incorrect type in argument 1 (different address spaces)
drivers/watchdog/imx7ulp_wdt.c:115:31:    expected struct watchdog_device *wdog
drivers/watchdog/imx7ulp_wdt.c:115:31:    got void [noderef] <asn:2>*base

Fixes: 747d88a1a8 ("watchdog: imx7ulp: Pass the wdog instance inimx7ulp_wdt_enable()")
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191120140916.25001-1-festevam@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-12-30 15:58:23 +01:00
Fabio Estevam
6083ab7b2f watchdog: imx7ulp: Fix reboot hang
The following hang is observed when a 'reboot' command is issued:

# reboot
# Stopping network: OK
Stopping klogd: OK
Stopping syslogd: OK
umount: devtmpfs busy - remounted read-only
[    8.612079] EXT4-fs (mmcblk0p2): re-mounted. Opts: (null)
The system is going down NOW!
Sent SIGTERM to all processes
Sent SIGKILL to all processes
Requesting system reboot
[   10.694753] reboot: Restarting system
[   11.699008] Reboot failed -- System halted

Fix this problem by adding a .restart ops member.

Fixes: 41b630f41b ("watchdog: Add i.MX7ULP watchdog support")
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191029174037.25381-1-festevam@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-11-18 19:53:44 +01:00
Fabio Estevam
eccb7fe5e7 watchdog: imx7ulp: Use definitions instead of magic values
Use definitions instead of magic values in order to improve readability.

Since the CLK field of the WDOG CS register is composed of two bits
to select the watchdog clock source, use a shift representation
instead of BIT().

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191029174037.25381-5-festevam@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-11-18 19:53:42 +01:00
Fabio Estevam
c37e358163 watchdog: imx7ulp: Remove inline annotations
Compiler is smart enough and knows when to inline, so there
is no need to mark some of these functions as 'inline'.

Remove such annotations.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191029174037.25381-4-festevam@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-11-18 19:53:42 +01:00
Fabio Estevam
9ab26e34bb watchdog: imx7ulp: Remove unused structure member
The 'notifier_block' structure member is unused, so just remove it.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191029174037.25381-3-festevam@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-11-18 19:53:42 +01:00
Fabio Estevam
747d88a1a8 watchdog: imx7ulp: Pass the wdog instance inimx7ulp_wdt_enable()
It is more natural to pass the watchdog instance inside
imx7ulp_wdt_enable() instead of the base address.

This also has the benefit to reduce the code a bit.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191029174037.25381-2-festevam@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-11-18 19:53:41 +01:00
Anson Huang
41b630f41b watchdog: Add i.MX7ULP watchdog support
The i.MX7ULP Watchdog Timer (WDOG) module is an independent timer
that is available for system use.
It provides a safety feature to ensure that software is executing
as planned and that the CPU is not stuck in an infinite loop or
executing unintended code. If the WDOG module is not serviced
(refreshed) within a certain period, it resets the MCU.

Add driver support for i.MX7ULP watchdog.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/1566999303-18795-2-git-send-email-Anson.Huang@nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-09-17 08:59:12 +02:00