Hi Timur On 31 October 2015 at 01:46, Timur Tabi <timur@xxxxxxxxxxxxxx> wrote: > On Tue, Oct 27, 2015 at 11:10 PM, Fu Wei <fu.wei@xxxxxxxxxx> wrote: >> >>> Why is WS1 optional? >> >> According to the description of WS1 in SBSA 2.3 (5.2 Watchdog Operation) page 21 >> ----------------- >> The signal is fed to a higher agent as an interrupt or reset for it to >> take executive action. >> ---------------- >> >> So WS1 maybe a interrupt. >> >> In a real Hardware, WS1 hooks to a reset signal pin of BMC, if this >> pin is triggered, BMC will do a real warm reset. >> In this case, WS1 is a reset, Linux doesn't need to deal with that. >> >> For now , I haven't found a hardware use WS1 as interrupt. >> In <ARM v8-A Foundation Platform User Guide> 3.2 Interrupt maps Page 22 >> Table 3-3 Shared peripheral interrupt assignments >> IRQ ID SPI offset Device >> 60 28 EL2 Generic Watchdog WS1 >> >> But I don't have further info about it. >> >> Anyway, because this signal could be interrupt or reset, Linux don't >> need know this signal sometimes. >> So I think it should be optional in binding info. >> >> Do I miss something? Any suggestion ? Please correct me, thanks. > > I think maybe Mark was asking why WS1 is optional, not the WS1 My answer is for "why WS1 is optional"! > interrupt. Maybe you can reword the documentation to make is clear > that I didn't say : "only the *interrupt* for WS1 is optional." > > However, the ACPI table only allows for one interrupt, and it's not > clear whether that's the WS0 or WS1 interrupt. So if both WS0 and WS1 > generate an interrupt, how does the driver handle that? register a interrupt handle for both > > -- > Qualcomm Innovation Center, Inc. > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project. -- Best regards, Fu Wei Software Engineer Red Hat Software (Beijing) Co.,Ltd.Shanghai Branch Ph: +86 21 61221326(direct) Ph: +86 186 2020 4684 (mobile) Room 1512, Regus One Corporate Avenue,Level 15, One Corporate Avenue,222 Hubin Road,Huangpu District, Shanghai,China 200021 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html