I tried reproducing the issue here but could not. Can you check if the device tree blob is correct?
Apalis iMX6 # run sdboot
Booting from SD card in 8-bit slot...
reading imx6q-apalis-ixora.dtb
44078 bytes read in 18 ms (2.3 MiB/s)
reading uImage
6571520 bytes read in 188 ms (33.3 MiB/s)
## Booting kernel from Legacy Image at 10800000 ...
Image Name: Linux-4.7.0-rc7-00092-g47ef4ad
Image Type: ARM Linux Kernel Image (uncompressed)
Data Size: 6571456 Bytes = 6.3 MiB
Load Address: 10008000
Entry Point: 10008000
Verifying Checksum ... OK
## Flattened Device Tree blob at 12000000
Booting using the fdt blob at 0x12000000
Loading Kernel Image ... OK
Using Device Tree in place at 12000000, end 1200dc2d
Starting kernel ...
[ 0.000000] Booting Linux on physical CPU 0x0
[ 0.000000] Linux version 4.7.0-rc7-00092-g47ef4ad (sanchayan@Sanchayan-Arch) (gcc version 5.2.1 20151005 (Linaro GCC 5.
2-2015.11-2) ) #56 SMP Thu Jul 21 11:44:28 IST 2016
[ 0.000000] CPU: ARMv7 Processor [412fc09a] revision 10 (ARMv7), cr=10c5387d
[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
[ 0.000000] Machine model: Toradex Apalis iMX6Q/D Module on Ixora Carrier Board
[ 0.000000] cma: Reserved 16 MiB at 0x8f000000
[ 0.000000] Memory policy: Data cache writealloc
[ 0.000000] percpu: Embedded 13 pages/cpu @e577f000 s24448 r8192 d20608 u53248
[ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 523056
[ 0.000000] Kernel command line: enable_wait_mode=off vmalloc=400M ip=off root=/dev/mmcblk1p2 rw,noatime rootfstype=ext3
rootwait fec_mac=00:14:2d:4b:16:04 consoleblank=0 no_console_suspend=1 console=tty1 console=ttymxc0,115200n8
[ 0.000000] PID hash table entries: 4096 (order: 2, 16384 bytes)
[ 0.000000] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
[ 0.000000] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
[ 0.000000] Memory: 2041048K/2097152K available (9220K kernel code, 436K rwdata, 2868K rodata, 1024K init, 8225K bss, 39
720K reserved, 16384K cma-reserved, 1449984K highmem)
[ 0.000000] Virtual kernel memory layout:
[ 0.000000] vector : 0xffff0000 - 0xffff1000 ( 4 kB)
[ 0.000000] fixmap : 0xffc00000 - 0xfff00000 (3072 kB)
[ 0.000000] vmalloc : 0xe7000000 - 0xff800000 ( 392 MB)
[ 0.000000] lowmem : 0xc0000000 - 0xe6800000 ( 616 MB)
[ 0.000000] pkmap : 0xbfe00000 - 0xc0000000 ( 2 MB)
[ 0.000000] modules : 0xbf000000 - 0xbfe00000 ( 14 MB)
[ 0.000000] .text : 0xc0008000 - 0xc0cce09c (13081 kB)
[ 0.000000] .init : 0xc0d00000 - 0xc0e00000 (1024 kB)
[ 0.000000] .data : 0xc0e00000 - 0xc0e6d3e0 ( 437 kB)
[ 0.000000] .bss : 0xc0e6f000 - 0xc16775e4 (8226 kB)
[ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
[ 0.000000] Running RCU self tests
[ 0.000000] Hierarchical RCU implementation.
[ 0.000000] RCU lockdep checking is enabled.
[ 0.000000] Build-time adjustment of leaf fanout to 32.
[ 0.000000] NR_IRQS:16 nr_irqs:16 16
[ 0.000000] L2C-310 erratum 769419 enabled
[ 0.000000] L2C-310 enabling early BRESP for Cortex-A9
[ 0.000000] L2C-310 full line of zeros enabled for Cortex-A9
[ 0.000000] L2C-310 ID prefetch enabled, offset 16 lines
[ 0.000000] L2C-310 dynamic clock gating enabled, standby mode enabled
[ 0.000000] L2C-310 cache controller enabled, 16 ways, 1024 kB
[ 0.000000] L2C-310: CACHE_ID 0x410000c7, AUX_CTRL 0x76070001
[ 0.000000] Switching to timer-based delay loop, resolution 333ns
[ 0.000007] sched_clock: 32 bits at 3000kHz, resolution 333ns, wraps every 715827882841ns
[ 0.000029] clocksource: mxc_timer1: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 637086815595 ns
[ 0.001494] Console: colour dummy device 80x30
[ 0.004056] console [tty1] enabled
[ 0.004086] Lock dependency validator: Copyright (c) 2006 Red Hat, Inc., Ingo Molnar
[ 0.004135] ... MAX_LOCKDEP_SUBCLASSES: 8
[ 0.004165] ... MAX_LOCK_DEPTH: 48
[ 0.004196] ... MAX_LOCKDEP_KEYS: 8191
[ 0.004226] ... CLASSHASH_SIZE: 4096
[ 0.004256] ... MAX_LOCKDEP_ENTRIES: 32768
[ 0.004288] ... MAX_LOCKDEP_CHAINS: 65536
[ 0.004322] ... CHAINHASH_SIZE: 32768
[ 0.004353] memory used by lock dependency info: 5167 kB
[ 0.004388] per task-struct memory footprint: 1536 bytes
[ 0.004448] Calibrating delay loop (skipped), value calculated using timer frequency.. 6.00 BogoMIPS (lpj=30000)
[ 0.004517] pid_max: default: 32768 minimum: 301
[ 0.004850] Mount-cache hash table entries: 2048 (order: 1, 8192 bytes)
[ 0.004901] Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes)
[ 0.006741] CPU: Testing write buffer coherency: ok
[ 0.007727] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000
[ 0.007851] Setting up static identity map for 0x10100000 - 0x10100070
[ 0.012923] CPU1: thread -1, cpu 1, socket 0, mpidr 80000001
[ 0.014745] CPU2: thread -1, cpu 2, socket 0, mpidr 80000002
[ 0.016234] CPU3: thread -1, cpu 3, socket 0, mpidr 80000003
[ 0.016449] Brought up 4 CPUs
[ 0.016592] SMP: Total of 4 processors activated (24.00 BogoMIPS).
[ 0.016634] CPU: All CPU(s) started in SVC mode.
The Angstrom Distribution apalis-imx6 ttymxc0
Angstrom v2015.12 - Kernel 4.7.0-rc7-00092-g47ef4ad
Apalis_iMX6_LinuxImageV2.6_20160630
apalis-imx6 login: root
Last login: Thu Jul 21 06:38:35 UTC 2016 on ttymxc0
root@apalis-imx6:~# uname -a
Linux apalis-imx6 4.7.0-rc7-00092-g47ef4ad #56 SMP Thu Jul 21 11:44:28 IST 2016 armv7l GNU/Linux
root@apalis-imx6:~#
defconfig used was imx_v6_v7_defconfig. Note that you might also need to change the rootfs and set the vidargs to blank. The mainline kernel does not use the vivante driver stuff from our current 3.14.52 kernel. One can use the Vybrid rootfs from our current release as it will have the modesetting driver for the display to work correctly with mainline.
