Re: [PATCH 1/3] powerpc: mac: fix rtc read functions

From: Andreas Schwab
Date: Mon Jun 18 2018 - 16:05:26 EST


On Jun 18 2018, Mathieu Malaterre <malat@xxxxxxxxxx> wrote:

> Sadly, trying again today does not work anymore. Adding some printk
> just before WARN_ON:
>
> +printk(KERN_ERR " rtc DBG pmu_get_time1: %lld %d %lld \n", now,
> RTC_OFFSET, now - RTC_OFFSET );
> +printk(KERN_ERR " rtc DBG pmu_get_time2: %x %x %x %x %d \n",
> req.reply[0], req.reply[1], req.reply[2], req.reply[3] ,
> req.reply_len);
>
> leads to:
>
> [ 0.000000] rtc DBG pmu_get_time1: 14096662 2082844800 -2068748138
> [ 0.000000] rtc DBG pmu_get_time2: 0 d7 19 16 4

A good value would have 0xd7 in the first byte. The problem is that
pmu_set_rtc_time is also broken, and leads to an invalid time value
stored in the RTC. Since pmu_request is a varargs function passing
values of type time64_t without casting won't work.

You need to reset your RTC before you can continue.

I think the right fix is to change nowtime in pmu_set_rtc_time and
cuda_set_rtc_time back to unsigned int (or to u32).

Andreas.

--
Andreas Schwab, schwab@xxxxxxxxxxxxxx
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