kernel/linux.git/drivers/watchdog/sbsa_gwdt.c, branch v7.0-rc2

watchdog: sbsa: Update the W_IIDR Implementer bit mask to 0xFFF

2026-01-18T09:55:09+00:00

The implementer mask defined in the driver [1] captures bits 0-10, whereas section C.4.2 of BSA specification [2] indicates that bits 0-11 of the W_IIDR register represent the implementer JEP106 code. Update the SBSA_GWDT_IMPL_MASK corresponding to bits 0-11, while at it update SBSA_GWDT_VERSION_MASK mask to use GENMASK. [1] #define SBSA_GWDT_IMPL_MASK 0x7FF [2] Implementer, bits [11:0] Contains the JEP106 code of the company that implemented the Generic Watchdog: Bits[11:8] The JEP106 continuation code of the implementer. Bit[7] Always 0 Bits [6:0] The JEP106 identity code of the implementer. Signed-off-by: Naina Mehta Acked-by: Aaron Plattner Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck

watchdog: sbsa: Adjust keepalive timeout to avoid MediaTek WS0 race condition

2025-07-28T10:07:08+00:00

The MediaTek implementation of the sbsa_gwdt watchdog has a race condition where a write to SBSA_GWDT_WRR is ignored if it occurs while the hardware is processing a timeout refresh that asserts WS0. Detect this based on the hardware implementer and adjust wdd->min_hw_heartbeat_ms to avoid the race by forcing the keepalive ping to be one second later. Signed-off-by: Aaron Plattner Acked-by: Timur Tabi Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20250721230640.2244915-1-aplattner@nvidia.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck

sbsa_gwdt: Calculate timeout with 64-bit math

2023-10-29T18:45:05+00:00

Commit abd3ac7902fb ("watchdog: sbsa: Support architecture version 1") introduced new timer math for watchdog revision 1 with the 48 bit offset register. The gwdt->clk and timeout are u32, but the argument being calculated is u64. Without a cast, the compiler performs u32 operations, truncating intermediate steps, resulting in incorrect values. A watchdog revision 1 implementation with a gwdt->clk of 1GHz and a timeout of 600s writes 3647256576 to the one shot watchdog instead of 300000000000, resulting in the watchdog firing in 3.6s instead of 600s. Force u64 math by casting the first argument (gwdt->clk) as a u64. Make the order of operations explicit with parenthesis. Fixes: abd3ac7902fb ("watchdog: sbsa: Support architecture version 1") Reported-by: Vanshidhar Konda Signed-off-by: Darren Hart Cc: Wim Van Sebroeck Cc: Guenter Roeck Cc: linux-watchdog@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: # 5.14.x Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/7d1713c5ffab19b0f3de796d82df19e8b1f340de.1695286124.git.darren@os.amperecomputing.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck

watchdog: Explicitly include correct DT includes

2023-08-13T12:29:49+00:00

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 Acked-by: Alim Akhtar Signed-off-by: Rob Herring Link: https://lore.kernel.org/r/20230726233302.3812749-1-robh@kernel.org Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck

watchdog: sbsa: Test WDOG_HW_RUNNING bit in suspend and resume

2023-04-22T10:53:53+00:00

If the sbsa_gwdt is enabled by BIOS, the kernel set WDOG_HW_RUNNING bit and keep it alive before anyone else would open it. When system suspend, the sbsa_gwdt would not be disabled because WDOG_ACTIVE is not set. Then the sbsa_gwdt would reach timeout since no one touch it during system suspend. To solve this, just test WDOG_HW_RUNNING bit in suspend and disable the sbsa_gwdt if the bit is set, then reopen it accordingly in resume process. Signed-off-by: Wang Wensheng Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20230301113702.76437-1-wangwensheng4@huawei.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck

watchdog: sbsa_wdog: Make sure the timeout programming is within the limits

2023-02-18T14:11:41+00:00

Make sure to honour the max_hw_heartbeat_ms while programming the timeout value to WOR. Clamp the timeout passed to sbsa_gwdt_set_timeout() to make sure the programmed value is within the permissible range. Fixes: abd3ac7902fb ("watchdog: sbsa: Support architecture version 1") Signed-off-by: George Cherian Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20230209021117.1512097-1-george.cherian@marvell.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck

watchdog: sbsa: drop unneeded MODULE_ALIAS

2021-10-26T18:22:51+00:00

The MODULE_DEVICE_TABLE already creates proper alias for platform driver. Having another MODULE_ALIAS causes the alias to be duplicated. Signed-off-by: Krzysztof Kozlowski Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20210917092024.19323-1-krzysztof.kozlowski@canonical.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck

watchdog: sbsa: only use 32-bit accessors

2021-10-26T18:22:50+00:00

SBSA says of the generic watchdog: All registers are 32 bits in size and should be accessed using 32-bit reads and writes. If an access size other than 32 bits is used then the results are IMPLEMENTATION DEFINED. and for qemu, the implementation will only allow 32-bit accesses resulting in a synchronous external abort when configuring the watchdog. Use lo_hi_* accessors rather than a readq/writeq. Fixes: abd3ac7902fb ("watchdog: sbsa: Support architecture version 1") Signed-off-by: Jamie Iles Reviewed-by: Guenter Roeck Reviewed-by: Shaokun Zhang Link: https://lore.kernel.org/r/20210903112101.493552-1-quic_jiles@quicinc.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck

watchdog: sbsa: Support architecture version 1

2021-06-21T06:48:58+00:00

For Armv8.6, The frequency of CNTFRQ_EL0 is standardized to a frequency of 1GHz, so Arm Base System Architecture 1.0[1] has introduced watchdog revision 1 that increases the length the watchdog offset register to 48 bit, while other operation of the watchdog remains the same. The driver can determine which version of the watchdog is implemented through the watchdog interface identification register (W_IID). If the version is 0x1, the watchdog offset register will be 48 bit, otherwise it will be 32 bit. [1] https://developer.arm.com/documentation/den0094/latest Cc: Wim Van Sebroeck Cc: Guenter Roeck Cc: Suravee Suthikulpanit Cc: Al Stone Cc: Jianchao Hu Cc: Huiqiang Wang Signed-off-by: Shaokun Zhang Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/1621253408-23401-1-git-send-email-zhangshaokun@hisilicon.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 294

2019-06-05T15:36:38+00:00

Based on 2 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 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 this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation this program is distributed in the hope that it [would] 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 9 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Alexios Zavras Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.804956444@linutronix.de Signed-off-by: Greg Kroah-Hartman