On Monday 14 February 2011, Dong, Chuanxiao wrote: > When I do trim with a 32GB eMMC card in my platform, sometimes I can get the 10s > timeout errors but sometimes not. I am not much clear about the "discarding partial > AU will take a lot longer". If this action is hide for driver, then I think from > driver side, the UINT_MAX value for max_discard_sectors will be OK. But if this action > sometimes need driver to wait for some hardware interrupt, then I think the UINT_MAX > value is not preferred. > > Arnd, have any suggestion of dealing this? What I thought is using other value > instead of using UINT_MAX. I'm not too familiar with the eMMC spec, but it should have a way to calculate a maximum trim timeout like SD 3.0 does for AU erases. When I've seen the timeouts with SDHCI (missing your patch), it was always a bug in the driver, and the erase was already completed before the driver even started waiting for the interrupt. 10 seconds still sounds like a reasonable timeout, and we should probably not issue any requests that might take longer than that, so I think the interesting question is how to determine a good value for pref_erase, so we can still take your patch. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
