Re: kern/60311: eMMC not powering up (used to work)

["Jared McNeill via gnats" <gnats-admin%NetBSD.org@localhost>]

The following reply was made to PR kern/60311; it has been noted by GNATS.

From: Jared McNeill <jmcneill%invisible.ca@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost, 
    martin%NetBSD.org@localhost
Subject: Re: kern/60311: eMMC not powering up (used to work)
Date: Sat, 6 Jun 2026 12:50:38 -0300 (ADT)

 On Fri, 5 Jun 2026, Martin Husemann via gnats wrote:
 
 > Fix suggested by mlelstv. This also affects netbsd-10 and netbsd-11.
 >
 > When we see an error from the host controller, delay the soft reset by 100us.
 >
 > Index: sys/dev/sdmmc/sdhc.c
 > ===================================================================
 > RCS file: /cvsroot/src/sys/dev/sdmmc/sdhc.c,v
 > retrieving revision 1.125
 > diff -u -p -r1.125 sdhc.c
 > --- sys/dev/sdmmc/sdhc.c	9 Jan 2026 22:54:34 -0000	1.125
 > +++ sys/dev/sdmmc/sdhc.c	5 Jun 2026 20:37:48 -0000
 > @@ -2356,8 +2356,10 @@ sdhc_wait_intr(struct sdhc_host *hp, int
 >
 >  	if (nointr ||
 >  	    (ISSET(status, SDHC_ERROR_INTERRUPT) && error)) {
 > -		if (!ISSET(hp->sc->sc_flags, SDHC_FLAG_ENHANCED))
 > +		if (!ISSET(hp->sc->sc_flags, SDHC_FLAG_ENHANCED)) {
 > +			sdmmc_delay(100);
 >  			(void)sdhc_soft_reset(hp, SDHC_RESET_CMD|SDHC_RESET_DAT);
 > +		}
 >  		hp->intr_error_status = 0;
 >  		status = 0;
 >  	}
 >
 > Without this second part I get random failures (differing between cold
 > boot and also changing after soft reboot). The most populare failures is
 > "unknown MMC version 6".
 
 The patch looks fine, but RK356x doesn't set SDHC_FLAG_ENHANCED, so I'm 
 struggling to see how this changes anything for you?
 
 When SDHC_FLAG_ENHANCED is NOT set, both with and without this patch, the 
 delay and sdhc_soft_reset lines will be executed. What am I missing?