On Wed, Jul 08, 2015 at 08:22:57AM +0200, Holger Schurig wrote: > Wow, at last some reaction. And I thought nobody cares ... > > BTW, removing CONFIG_MMC_CLKGATE helped a bit, because the pointless > clock-off-clock-on while the device is booting (or accessing multiple > sectors within a short time) isn't going to happen anymore. > > But really, a mdelay(1) in a driver ... Look for the other mdelays in sdhci.c. There are up to a hundred of them in sdhci_reset() which is called under a spin_lock_irqsave. I remember that with the wrong type of card detection the MMC core frequently polls for a card and if none is found the sdhci core was resetted which falls into this mdelay polling loop in sdhci_reset. So if you care about realtime you better have a card inserted... Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- 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