From: "Herbrechtsmeier Dr.-Ing. , Stefan" <stefan.herbrechtsmeier-oss-2t/0UIm1CeVDOHtkgc7UlQ@public.gmane.org>
To: Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Execute spi transfers inside FIQ (NMI) or panic
Date: Tue, 25 Feb 2020 14:27:27 +0100 [thread overview]
Message-ID: <b22800b8-9c03-63a5-7ade-d8b63c562580@weidmueller.com> (raw)
Hi,
would it be acceptable to add an additional function to the struct
spi_controller which handle a transfer inside a NMI context or a panic?
The new function will transfer data via register polling without any lock.
I must execute an SPI transfer inside a fast interrupt request (FIQ)
handler or a panic. The FIQ is handled as a non-maskable interrupt
(NMI). Both the panic and the NMI doesn't support any interrupts.
The background of the request is a non-volatile SPI memory with cached
date in system memory. The cache must be synchronized back to the SPI
memory after a power failure or panic.
Regards
Stefan Herbrechtsmeier
**
next reply other threads:[~2020-02-25 13:27 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-25 13:27 Herbrechtsmeier Dr.-Ing. , Stefan [this message]
[not found] ` <b22800b8-9c03-63a5-7ade-d8b63c562580-2t/0UIm1CeVDOHtkgc7UlQ@public.gmane.org>
2020-02-25 15:53 ` Execute spi transfers inside FIQ (NMI) or panic Mark Brown
[not found] ` <20200225155354.GF4633-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2020-02-26 7:36 ` Herbrechtsmeier Dr.-Ing. , Stefan
[not found] ` <d07a46e6-6c8f-c4eb-0ed1-d57b7604a5be-2t/0UIm1CeVDOHtkgc7UlQ@public.gmane.org>
2020-02-26 11:33 ` Mark Brown
[not found] ` <20200226113333.GC4136-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2020-02-26 15:28 ` Herbrechtsmeier Dr.-Ing. , Stefan
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