On Mon, 14 Sep 2015 13:43:32 +0530 Vaibhav Hiremath <vaibhav.hiremath@xxxxxxxxxx> wrote: > > > On Monday 14 September 2015 11:58 AM, Jisheng Zhang wrote: > > On Mon, 14 Sep 2015 11:55:56 +0530 > > Vaibhav Hiremath <vaibhav.hiremath@xxxxxxxxxx> wrote: > > > >> > >> > >> On Thursday 10 September 2015 01:34 PM, Jisheng Zhang wrote: > >>> Hi Russell, > >>> > >>> On Thu, 10 Sep 2015 09:02:33 +0100 > >>> Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: > >>> > >>>> On Thu, Sep 10, 2015 at 03:31:29PM +0800, Jisheng Zhang wrote: > >>>>> Hi Vaibhav, > >>>>> > >>>>> On Thu, 10 Sep 2015 12:40:48 +0530 > >>>>> Vaibhav Hiremath <vaibhav.hiremath@xxxxxxxxxx> wrote: > >>>>> > >>>>>> Hi, > >>>>>> > >>>>>> During my testing of SDHCI-PXAV3 driver on Marvell's pxa1928 > >>>>>> based platform, I observed that runtime PM suspend/resume is having > >>>>>> issues with card insertion and removal. > >>>>>> > >>>>>> Let me try to explain it using execution sequence - > >>>>>> > >>>>>> During boot: > >>>>>> > >>>>>> MMC SD card gets detected as expected. > >>>>>> > >>>>>> [ 2.431012] mmc1: new high speed SDHC card at address 1234 > >>>>>> [ 2.437235] mmcblk1: mmc1:1234 SA04G 3.63 GiB > >>>>>> [ 2.444841] mmcblk1: p1 > >>>>>> > >>>>>> > >>>>>> Now after coming to the linux prompt, if card removal event occurs > >>>>>> then the call sequence is - > >>>>>> > >>>>>> sdhci_irq() --> > >>>>>> -> sdhci_thread_irq(): host->thread_isr - 0x80 > >>>>>> -> sdhci_card_event() > >>>>>> -> mmc_detect_change() > >>>>>> --> _mmc_detect_change() > >>>>>> ---> mmc_sd_detect() > >>>>>> mmc_sd_remove() > >>>>>> mmc_remove_card() > >>>>>> mmc_bus_remove() > >>>>>> mmc_power_off() > >>>>>> mmc_set_initial_state() > >>>>>> sdhci_set_ios() > >>>>>> ... > >>>>>> sdhci_pxav3_runtime_suspend() > >>>>>> sdhci_runtime_suspend_host() > >>>>>> > >>>>>> > >>>>>> Till here everything looks perfect :) (if I got it right) > >>>>>> > >>>>>> Now on card insertion again, the expectation is, runtime resume should > >>>>>> get called as part of interrupt trigger from the SDHCI controller on > >>>>>> card insertion. > >>>>> > >>>>> AFAIK, card insertion => wakeup irq, this irq doesn't come from SDHCI > >>>> > >>>> Wakeup IRQs are what happens when the _system_ is in suspend, not > >>>> when the device is runtime suspended. > >>> > >>> Oh, yes. Sorry for misleading, I didn't express myself clearly. What > >>> I really means is that the card insertion/remove irq which could finally > >>> cause sdhci host resumed. > >>> > >> > >> So Jisheng, > >> > >> You are ok with above change, right? > > > > Nope. the above is just to clarify my mixing "wakeup IRQs" and the card > > insertion/remove irq that brings sdhci host resumed. > > > > IMHO, your patch is still not necessary and perhaps wrong. > > > > Don't be in hurry to conclude, > Let's understand the technical aspect fist. > > > Let me clarify once again here, > > > The card detect interrupt is coming from SDHCI controller itself, But how the SDHCI controller generate CD interrupt when it's in runtime suspended state, i.e clock gated or power gated? > I have confirmed that the runtime PM is working perfectly fine, > clock is gated/disabled on card removal. But seems we still didn't know the sdhci host is clock gated or power gated. > > > Clock Gating: > ============= > # > # devmem 0xd4282854 > 0x0000181B > # [ 1318.948460] mmc1: card 1234 removed > > # > # devmem 0xd4282854 > 0x00001800 > # Can you plz read the SDHCI host registers after this step? If the host is clock gated, we should get "asynchronous external abort" in theory. Thanks -- 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
