The watchdog controller on the Meson-A/C series SoCs is moved to secure world, We have to call SMC instruction to trap the ATF for watchdog operation. These operations are different from previous SoCs, so we introduce a new watchdog driver to support this kind of SoCs. Changes since v5 at [4]: - take the wdt node as child node of secure-monitor - update dt-binding description - invoke of_platform_default_populate() instantiate wdt device according to Rob's suggestion at [5] - find the secure-monitor node through the wdt parent node instead of of_find_compatible_node() - add Guenter's Reviewed-by Changes since v4 at [3]: - add watchdog node in dts, and introduce a new optional property "timeout-sec" - add dt-binding for meson secure watchdog - instantiate wdt device through dts node instead of platform_device_register_simple() Changes since v3 at [2]: - add SM_A1_ prefix for WATCHDOG_OPS - remove phandle to secure-monitor node - remove watchdog node from dts, and register wdt device by platform_device_register_simple() - remove dt-binding for meson secure watchdog - use the msec as unit of timeout parameter which is passed to fw side Changes since v2 at [1]: - remove useless dependency in Kconfig - return zero when getting left time value fails Changes since v1 at [0]: - add a new dependency in Kconfig - simplify/add the return operation - remove useless ping operation when setting the timeout - fix some return values - fix the license statement [0]:https://lore.kernel.org/linux-amlogic/1570874721-36077-1-git-send-email-xingyu.chen@xxxxxxxxxxx [1]:https://lore.kernel.org/linux-amlogic/1571387622-35132-1-git-send-email-xingyu.chen@xxxxxxxxxxx [2]:https://lore.kernel.org/linux-amlogic/1571983984-11771-1-git-send-email-xingyu.chen@xxxxxxxxxxx [3]:https://lore.kernel.org/linux-amlogic/1574685218-31164-1-git-send-email-xingyu.chen@xxxxxxxxxxx [4]:https://lore.kernel.org/linux-amlogic/1576153187-28378-1-git-send-email-xingyu.chen@xxxxxxxxxxx [5]:https://patchwork.kernel.org/patch/11288017 Xingyu Chen (5): firmware: meson_sm: add new SMC ID support for accessing secure watchdog firmware: meson_sm: populate platform device based on the child node dt-bindings: watchdog: add new binding for meson secure watchdog watchdog: add meson secure watchdog driver arm64: dts: a1: add secure watchdog controller .../bindings/watchdog/amlogic,meson-sec-wdt.yaml | 40 +++++ arch/arm64/boot/dts/amlogic/meson-a1.dtsi | 6 + drivers/firmware/meson/meson_sm.c | 3 + drivers/watchdog/Kconfig | 16 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/meson_sec_wdt.c | 185 +++++++++++++++++++++ include/linux/firmware/meson/meson_sm.h | 1 + 7 files changed, 252 insertions(+) create mode 100644 Documentation/devicetree/bindings/watchdog/amlogic,meson-sec-wdt.yaml create mode 100644 drivers/watchdog/meson_sec_wdt.c -- 2.7.4
