AnsweredAssumed Answered

Configure default MMC

Question asked by danielbujak on Aug 25, 2017
Latest reply on Sep 8, 2017 by danielbujak

How does one select which MMC the kernel checks for the rootfs? I have a wifi module connected to usdhc1 that is disabled on boot but configured in the dts. When the kernel boots it keeps waiting for this device to become available which it wont be until the rootfs on usdhc2 is mounted and the i2c driver can run to initialize the PMIC controlling the wifi module.

 

Is it possible to have the kernel boot from MMC1 (usdhc2) by default? Here's the output of my log (note: eventually it gives up on mmc0 and boots from mmc1 but this takes 5 minutes)

 

...

8021q: 802.1Q VLAN Support v1.8
lib80211: common routines for IEEE802.11 drivers
Key type dns_resolver registered
input: gpio_keys as /devices/platform/gpio_keys/input/input1
snvs_rtc 20cc000.snvs:snvs-rtc-lp: setting system clock to 1970-01-01 00:00:01 UTC (1)
can-3v3: disabling
ALSA device list:
  No soundcards found.
Waiting for root device /dev/mmcblk1p2...
mmc0: Timeout waiting for hardware interrupt.
mmc0: Timeout waiting for hardware interrupt.
mmc0: Timeout waiting for hardware interrupt.
...
mmc0: Timeout waiting for hardware interrupt.
mmc0: Timeout waiting for hardware interrupt.
mmc0: Timeout waiting for hardware interrupt.
mmc1: host does not support reading read-only switch, assuming write-enable
mmc1: new SD card at address a153
mmcblk1: mmc1:a153 SU02G 1.84 GiB
 mmcblk1: p1 p2
EXT3-fs (mmcblk1p2): error: couldn't mount because of unsupported optional features (240)
EXT2-fs (mmcblk1p2): error: couldn't mount because of unsupported optional features (240)
EXT4-fs (mmcblk1p2): mounted filesystem with ordered data mode. Opts: (null)
VFS: Mounted root (ext4 filesystem) on device 179:2.
devtmpfs: mounted
Freeing unused kernel memory: 428K (80a4d000 - 80ab8000)
EXT4-fs (mmcblk1p2): re-mounted. Opts: data=ordered
devpts: called with bogus options
Starting logging: OK
Starting PMIC VLDO3: usage: /bin/pf3001 <option>
options: read, write
usage: /bin/pf3001 <option>
options: read, write
OK
Initializing random number generator... done.
Starting system message bus: done
Starting network: OK
Starting connman ... done.
Starting dropbear sshd: OK

 

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