[Skiboot] [PATCH] FSP/RTC: Fix possible FSP R/R issue in rtc write path
hegdevasant at linux.vnet.ibm.com
Tue Jun 13 23:11:23 AEST 2017
On 06/13/2017 03:52 PM, Vasant Hegde wrote:
> fsp_opal_rtc_write() checks FSP status before queueing message to FSP. But if
> FSP R/R starts before getting response to queued message then we will continue
> to return OPAL_BUSY_EVENT to host. In some extreme condition host may
> experience hang. Once FSP is back we will repost message, get response from FSP
> and return OPAL_SUCCES to host.
> This patch caches new values and returns OPAL_SUCCESS if FSP R/R is happening.
> And once FSP is back we will send cached value to FSP.
I missed to add "v2" to subject line. Please consider this patch. Not v1 patch.
With this changes, OPAL will record new request from kernel while FSP is in reboot.
Once FSP is back OPAL will call rtc_flush_cached_tod() to flush the data.
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