Hi, On Wed, Aug 31, 2016 at 7:29 PM, Ziyuan Xu <xzy.xu@xxxxxxxxxxxxxx> wrote: >> This is fine to pick up _only_ if you don't care about suspend/resume. >> If you care about suspend/resume then someone needs to first write a >> patch that will re-init all "corecfg" values after power is turned on. > > > Do you mean corecfg_clockmultiplier and corecfg_baseclkfreq, if yes, we > don't need to strore/re-init it after resume. > corecfg_clockmultiplier is only used to fetch host->clk_mul, and > host->clk_mul has been a fixed value at run-time, unless driver unbind. > The same as corecfg_clockmultiplier, corecfg_baseclkfreq is used to check > the xin_clk at probe time, we don't reference it at run-time. > BTW, I have tested suspend/resume on rk3399 prior to this sumbit, eMMC works > fine. I guess I don't actually know how the corecfg_clockmultiplier and corecfg_baseclkfreq fields are actually used, but I presume that they actually do something useful and aren't used to just communicate back to software? I know that: 1. If I don't pick this patch and I suspend/resume, corecfg_clockmultiplier and corecfg_baseclkfreq are still fine after suspend / resume. 2. If I do pick this patch and I suspend/resume, corecfg_clockmultiplier and corecfg_baseclkfreq are wrong after suspend/resume (tested by reading /dev/mem directly from userspace after suspend/resume). Are you saying that it is unimportant that corecfg_clockmultiplier and corecfg_baseclkfreq are wrong? >> Technically I think this should probably use "pm runtime" and not >> normal suspend/resume hooks. Any time we end up pm runtime suspended >> then I think our power will go off (because of genpd?) and we need to >> restore values. > > > I understand your consideration. BUT genpd is in charge of on/off pd if the > corresponding device node has "power-domains" property. RPM is unnecessary > for this situation, we will not use autosuspend, right? > > @shawn, what's your opinion? I haven't dug. If Runtime PM isn't enabled for sdhci-of-arasan then I guess we can just worry about suspend/resume, though. -Doug -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
