From: Fu Wei fu.wei@linaro.org
This patchset: (1)Introduce Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt for FDT info of SBSA Generic Watchdog, and give two examples of adding SBSA Generic Watchdog device node into the dts files: foundation-v8.dts and amd-seattle-soc.dtsi.
(2)Introduce "pretimeout" into the watchdog framework, and update Documentation/watchdog/watchdog-kernel-api.txt to introduce: (1)the new elements in the watchdog_device and watchdog_ops struct; (2)the new API "watchdog_init_timeouts".
(3)Introduce ARM SBSA watchdog driver: a.Use linux kernel watchdog framework; b.Work with FDT on ARM64; c.Use "pretimeout" in watchdog framework; d.Support getting timeout and pretimeout from parameter and FDT at the driver init stage. e.In the first timeout, do panic to save system context; f.In the second stage, user can still feed the dog without cleaning WS0. By this feature, we can avoid the panic infinite loops, while backing up a large system context in a server. g.In the second stage, can trigger WS1 by setting pretimeout = 0 if necessary.
This patchset has been tested with watchdog daemon (ACPI/FDT, module/build-in) on the following platforms: (1)ARM Foundation v8 model (2)AMD Seattle platform
This patchset has been tested with kdump successfully.
Changelog: v9: Rebase to latest kernel version(4.3). Update the Documentation of sbsa-gwdt device node info of FDT: (1) move some introduction to pretimeout patch (2) delete WS1 value from "interrupts" of binding documentation, since WS1 won't be handled by Linux.
v8: Rebase to latest kernel version(4.3-rc7). Separate the patches of GTDT support and arm_arch_timer. This clocksource relevant patch will upstreamed in a individual patchset. Update all the default timeout and pretimeout to 30s and 60s. Improve documentation and inline comments. Fix a bug in pretimeout support which makes timeout and pretimeout parameters initialization fail.
v7: Rebase to latest kernel version(4.2-rc7). Improve FDT support: geting resource by order, instead of name. According to the FDT support, Update the example dts file, gtdt.c and sbsa_gwdt.c. Pass the sparse test, and fix the warning. Fix the max_pretimeout and max_timeout value overflow bug. Delete the WCV output value.
v6: Improve the dtb example files: reduce the register frame size to 4K. Improve pretimeout support: (1) improve watchdog_init_timeouts function (2) rename watchdog_check_min_max_timeouts back to the original name (1) improve watchdog_timeout_invalid/watchdog_pretimeout_invalid Add the new features in the sbsa_gwdt driver: (1) In the second stage, user can feed the dog without cleaning WS0. (2) In the second stage, user can trigger WS1 by setting pretimeout = 0. (3) expand the max value of pretimeout, in case 10 second is not enough for a kdump kernel reboot in panic.
v5: Improve pretimeout support: (1)fix typo in documentation and comments. (2)fix the timeout limits validation bug. Simplify sbsa_gwdt driver: (1)integrate all the registers access functions into caller.
v4: Refactor GTDT support code: remove it from arch/arm64/kernel/acpi.c, put it into drivers/acpi/gtdt.c file. Integrate the GTDT code of drivers/clocksource/arm_arch_timer.c into drivers/acpi/gtdt.c. Improve pretimeout support, fix "pretimeout == 0" problem. Simplify sbsa_gwdt driver: (1)timeout/pretimeout limits setup; (2)keepalive function; (3)delete "clk == 0" check; (4)delete WS0 status bit check in interrupt routine; (5)sbsa_gwdt_set_wcv function.
v3: Delete "export arch_timer_get_rate" patch. Driver back to use arch_timer_get_cntfrq. Improve watchdog_init_timeouts function and update relevant documentation. Improve watchdog_timeout_invalid and watchdog_pretimeout_invalid. Improve foundation-v8.dts: delete the unnecessary tag of device node. Remove "ARM64 || COMPILE_TEST" from Kconfig. Add comments in arch/arm64/kernel/acpi.c Fix typoes and incorrect comments.
v2: Improve watchdog-kernel-api.txt documentation for pretimeout support. Export "arch_timer_get_rate" in arm_arch_timer.c. Add watchdog_init_timeouts API for pretimeout support in framework. Improve suspend and resume foundation in driver Improve timeout/pretimeout values init code in driver. Delete unnecessary items of the sbsa_gwdt struct and #define. Delete all unnecessary debug info in driver. Fix 64bit division bug. Use the arch_timer interface to get watchdog clock rate. Add MODULE_DEVICE_TABLE for platform device id. Fix typoes.
v1: The first version upstream patchset to linux mailing list.
Fu Wei (5): Documentation: add sbsa-gwdt driver documentation ARM64: add SBSA Generic Watchdog device node in foundation-v8.dts ARM64: add SBSA Generic Watchdog device node in amd-seattle-soc.dtsi Watchdog: introdouce "pretimeout" into framework Watchdog: introduce ARM SBSA watchdog driver
.../devicetree/bindings/watchdog/sbsa-gwdt.txt | 34 ++ Documentation/watchdog/watchdog-kernel-api.txt | 61 ++- Documentation/watchdog/watchdog-parameters.txt | 6 + arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi | 8 + arch/arm64/boot/dts/arm/foundation-v8.dts | 7 + drivers/watchdog/Kconfig | 14 + drivers/watchdog/Makefile | 1 + drivers/watchdog/sbsa_gwdt.c | 459 +++++++++++++++++++++ drivers/watchdog/watchdog_core.c | 127 ++++-- drivers/watchdog/watchdog_dev.c | 53 +++ include/linux/watchdog.h | 39 +- 11 files changed, 767 insertions(+), 42 deletions(-) create mode 100644 Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt create mode 100644 drivers/watchdog/sbsa_gwdt.c