u-boot.git/drivers/watchdog/qcom-wdt.c, branch master Unnamed repository; edit this file 'description' to name the repository. watchdog: qcom: stop watchdog by default 2026-03-24T10:51:52+00:00 Casey Connolly casey.connolly@linaro.org 2026-01-21T00:36:51+00:00 1cf505e51b49438271f4b36a648b93b618f13a8e Prevent the Qualcomm watchdog from autostarting and ensure it's stopped when the driver probed. In some cases the watchdog is left running by a previous bootloader stage. Disable autostart so it isn't left running when we boot into the OS, this behaviour can be changed by enabling autostart in the board defconfig. Reviewed-by: Stefan Roese <stefan.roese@mailbox.org> Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com> Reviewed-by: Tom Rini <trini@konsulko.com> Link: https://patch.msgid.link/20260121003659.69305-1-casey.connolly@linaro.org Signed-off-by: Casey Connolly <casey.connolly@linaro.org> 
Prevent the Qualcomm watchdog from autostarting and ensure it's stopped
when the driver probed. In some cases the watchdog is left running by
a previous bootloader stage. Disable autostart so it isn't left running
when we boot into the OS, this behaviour can be changed by enabling
autostart in the board defconfig.

Reviewed-by: Stefan Roese <stefan.roese@mailbox.org>
Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Link: https://patch.msgid.link/20260121003659.69305-1-casey.connolly@linaro.org
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>
watchdog: qcom: Add max timeout check to prevent overflow 2026-01-14T15:17:48+00:00 Gopinath Sekar gopinath.sekar@oss.qualcomm.com 2025-06-25T09:46:07+00:00 b2446a2314310971563c0279345bbd3293614e33 Added a check to ensure the requested timeout does not exceed the hardware's maximum supported value. This prevents register overflow and ensures watchdog reliability. So, added a check in qcom_wdt_start() to ensure the requested timeout does not exceed the hardware-supported maximum value. If the requested value exceeds the maximum value, then the timeout is clamped at maximum value. The timeout is first converted to watchdog ticks and then compared against QCOM_WDT_MAX_TIMEOUT. This helps prevent misconfiguration and potential watchdog misbehavior due to overflow. QCOM_WDT_MAX_TIMEOUT is set to 0xFFFFF, as Qualcomm SoCs typically use 20 bits to store bark/bite timeout values. This work builds upon the previous submission: https://lore.kernel.org/u-boot/20250527124926.128413-1-balaji.selvanathan@oss.qualcomm.com/ Signed-off-by: Gopinath Sekar <gopinath.sekar@oss.qualcomm.com> Reviewed-by: Stefan Roese <sr@denx.de> Link: https://patch.msgid.link/20250625094607.1348494-1-gopinath.sekar@oss.qualcomm.com Signed-off-by: Casey Connolly <casey.connolly@linaro.org> 
Added a check to ensure the requested timeout does not exceed the
hardware's maximum supported value. This prevents register overflow
and ensures watchdog reliability.

So, added a check in qcom_wdt_start() to ensure the requested timeout
does not exceed the hardware-supported maximum value. If the requested
value exceeds the maximum value, then the timeout is clamped
at maximum value.

The timeout is first converted to watchdog ticks and then compared
against QCOM_WDT_MAX_TIMEOUT. This helps prevent misconfiguration
and potential watchdog misbehavior due to overflow.

QCOM_WDT_MAX_TIMEOUT is set to 0xFFFFF, as Qualcomm SoCs typically
use 20 bits to store bark/bite timeout values.

This work builds upon the previous submission:
https://lore.kernel.org/u-boot/20250527124926.128413-1-balaji.selvanathan@oss.qualcomm.com/

Signed-off-by: Gopinath Sekar <gopinath.sekar@oss.qualcomm.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Link: https://patch.msgid.link/20250625094607.1348494-1-gopinath.sekar@oss.qualcomm.com
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>
watchdog: qcom-wdt: Drop read check on write-only WDT_EN register 2025-07-14T13:35:24+00:00 Balaji Selvanathan balaji.selvanathan@oss.qualcomm.com 2025-07-01T06:57:38+00:00 9cd3118e4aa693caed6ee3fe8ef1e0b91f004484 On some Qualcomm platforms, such as Dragonwing boards, the WDT_EN register is write-only. Reading it back after enabling the watchdog can return invalid data or cause unexpected behavior. In particular, the check: if (readl(wdt_addr(wdt, WDT_EN)) != 1) may fail even though the watchdog is correctly enabled and running. This leads to misleading error messages and unnecessary failures. Removing the read check ensures compatibility and avoids false negatives on platforms where WDT_EN is not readable. This work builds upon this previous submission: https://lore.kernel.org/u-boot/20250625094607.1348494-1-gopinath.sekar@oss.qualcomm.com/ Signed-off-by: Balaji Selvanathan <balaji.selvanathan@oss.qualcomm.com> Reviewed-by: Stefan Roese <sr@denx.de> Link: https://lore.kernel.org/r/20250701065738.1644669-1-balaji.selvanathan@oss.qualcomm.com Signed-off-by: Casey Connolly <casey.connolly@linaro.org> 
On some Qualcomm platforms, such as Dragonwing boards, the WDT_EN
register is write-only. Reading it back after enabling the watchdog
can return invalid data or cause unexpected behavior.

In particular, the check:
  if (readl(wdt_addr(wdt, WDT_EN)) != 1)
may fail even though the watchdog is correctly enabled and running.
This leads to misleading error messages and unnecessary failures.

Removing the read check ensures compatibility and avoids false
negatives on platforms where WDT_EN is not readable.

This work builds upon this previous submission:
https://lore.kernel.org/u-boot/20250625094607.1348494-1-gopinath.sekar@oss.qualcomm.com/

Signed-off-by: Balaji Selvanathan <balaji.selvanathan@oss.qualcomm.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Link: https://lore.kernel.org/r/20250701065738.1644669-1-balaji.selvanathan@oss.qualcomm.com
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>
drivers: watchdog: qcom: Add timeout configuration support in watchdog 2025-06-23T16:50:39+00:00 Balaji Selvanathan balaji.selvanathan@oss.qualcomm.com 2025-05-27T12:49:26+00:00 35811a7b0d68ce1a32446953e3ccf7a2186f08f8 This patch enhances the Qualcomm watchdog driver by introducing support for dynamic timeout configuration. Specifically: - Calculates and sets the bark and bite timeout values based on the clock rate and the requested timeout in milliseconds. - Adds retrieval of the watchdog clock rate during probe using the common clock framework. - Adds a default timeout value for ARCH_SNAPDRAGON in WATCHDOG_TIMEOUT_MSECS. These changes improve the configurability and accuracy of the watchdog timer on Qualcomm platforms. This work builds upon the previous submission: https://lore.kernel.org/all/20250422-b4-qcom-wdt-v3-1-730d4d5a858d@paulsajna.com/ Signed-off-by: Balaji Selvanathan <balaji.selvanathan@oss.qualcomm.com> Link: https://lore.kernel.org/r/20250527124926.128413-1-balaji.selvanathan@oss.qualcomm.com Signed-off-by: Casey Connolly <casey.connolly@linaro.org> 
This patch enhances the Qualcomm watchdog driver by introducing
support for dynamic timeout configuration. Specifically:

- Calculates and sets the bark and bite timeout values based on
  the clock rate and the requested timeout in milliseconds.
- Adds retrieval of the watchdog clock rate during probe using
  the common clock framework.
- Adds a default timeout value for ARCH_SNAPDRAGON
  in WATCHDOG_TIMEOUT_MSECS.

These changes improve the configurability and accuracy of the
watchdog timer on Qualcomm platforms.

This work builds upon the previous submission:
https://lore.kernel.org/all/20250422-b4-qcom-wdt-v3-1-730d4d5a858d@paulsajna.com/

Signed-off-by: Balaji Selvanathan <balaji.selvanathan@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250527124926.128413-1-balaji.selvanathan@oss.qualcomm.com
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>
watchdog: qcom: introduce qcom-wdt driver 2025-06-23T16:50:38+00:00 Casey Connolly casey.connolly@linaro.org 2025-04-23T02:19:39+00:00 530764de9fc8539cd2354501e9c42804bc4c4dac Some Qualcomm device vendors decide to turn the watchdog on in the bootloader, resulting in the device being reset if it isn't petted every ~30 seconds. Introduce a driver to keep the watchdog happy and prevent this annoying behaviour. Signed-off-by: Paul Sajna <hello@paulsajna.com> Co-authored-by: Paul Sajna <hello@paulsajna.com> Tested-by: Paul Sajna <hello@paulsajna.com> Reviewed-by: Stefan Roese <sr@denx.de> Acked-by: Sumit Garg <sumit.garg@oss.qualcomm.com> Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org> Link: https://lore.kernel.org/r/20250422-b4-qcom-wdt-v3-1-730d4d5a858d@paulsajna.com Signed-off-by: Casey Connolly <casey.connolly@linaro.org> 
Some Qualcomm device vendors decide to turn the watchdog on in the
bootloader, resulting in the device being reset if it isn't petted every
~30 seconds. Introduce a driver to keep the watchdog happy and prevent this
annoying behaviour.

Signed-off-by: Paul Sajna <hello@paulsajna.com>
Co-authored-by: Paul Sajna <hello@paulsajna.com>
Tested-by: Paul Sajna <hello@paulsajna.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Acked-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20250422-b4-qcom-wdt-v3-1-730d4d5a858d@paulsajna.com
Signed-off-by: Casey Connolly <casey.connolly@linaro.org>