[alsa-devel] [PATCH 4/4] ASoC: fsl: make fsl_ssi driver compilable on ARM/IMX
timur at freescale.com
Thu Feb 23 18:04:59 CET 2012
Russell King - ARM Linux wrote:
> Is your readl() or readl_be() unordered then?
Yes. At least, it sure looks like it is.
> Wouldn't that be buggy
> between coherent DMA accesses and accessing, eg, a PCI peripheral to
> enable or read DMA status?
I think so.
We almost never use readl. I see that it is used in some places, but
honestly I can't see how it can be valid. For instance, the mpic driver
uses it in mpic_startup_ht_interrupt(). I don't understand how that's
valid, since there's nothing preventing the readl() from happening
*before* the writeb.
I'll have to ask around, because I'm sure I'm missing something.
Linux kernel developer at Freescale
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