On 7/13/23 02:51, huaqian.li@xxxxxxxxxxx wrote:
From: Li Hua Qian <huaqian.li@xxxxxxxxxxx> The watchdog hardware of TI AM65X platform does not support WDIOF_CARDRESET feature, add a reserved memory to save the watchdog reset cause, to know if the board reboot is due to a watchdog reset.
One thing I keep wondering about: What prevents the Linux kernel from treating the special memory area like normal memory ? I would have expected some usage note, such as that the memory area must be reported as reserved to the kernel, but I don't see anything like that. Guenter
Changes in v3: - Add memory-region back for the reserved memory, and remove reserved memory from the watchdog IO address space. - Add changelog. - Link to v2: https://lore.kernel.org/linux-watchdog/20230711091713.1113010-1-huaqian.li@xxxxxxxxxxx Changes in v2: - Remove memory-region and memory-size properties, and bind the reserved memory to watchdog IO address space. - Remove the unnecessary rti_wdt_ioctl. - Fix the mail list - Link to v1: https://lore.kernel.org/all/3137d87e56ef75ba0b8a923d407b2fecace6ccbd.camel@xxxxxxxxxxx/ v1 had a wrong mail list at the beginning, and the mail thread was messed up. Li Hua Qian (3): dt-bindings: watchdog: ti,rti-wdt: Add support for WDIOF_CARDRESET arm64: dts: ti: Add reserved memory for watchdog watchdog:rit_wdt: Add support for WDIOF_CARDRESET .../bindings/watchdog/ti,rti-wdt.yaml | 12 +++++ .../boot/dts/ti/k3-am65-iot2050-common.dtsi | 10 ++++ drivers/watchdog/rti_wdt.c | 51 +++++++++++++++++++ 3 files changed, 73 insertions(+)
