Messages in this thread | | | Date | Mon, 30 Oct 2023 17:12:01 -0700 | Subject | Re: [PATCH v2] i2c: designware: Fix corrupted memory seen in the ISR | From | Jan Bottorff <> |
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On 10/26/2023 4:18 AM, Wolfram Sang wrote: > So, someone wants to come up with a patch to move to non-relaxed io > accessors? > Is the current thinking to just make writes to DW_IC_INTR_MASK use the non-relaxed variant or something more broad?
From a safest functioning viewpoint, we talked about making all accessors default to non-relaxed variants. A couple of pretty good arguments from knowledgeable people favored this. I know there also was some concerns about potential performance impact this might have although the counter argument was this is a pretty low speed device so some extra cpu cycles on register accesses were not likely to degrade overall performance.
I could make the patch if we have consensus (or maintainers decision) on which way to go: 1) only writes to DW_IC_INTR_MASK are non-relaxed, 2) make all read/write accessors use the non-relaxed version.
I'm personally in camp #2, safety first, performance fine tuning later if needed. Latent missing barrier bugs are difficult and time consuming to find.
- Jan
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