[3rdparty PATCH 0/4] Allow easier use of mainline-based BSP on i.MX products (Nitrogen6x support)

[3rdparty PATCH 0/4] Allow easier use of mainline-based BSP on i.MX products (Nitrogen6x support)

[Otavio Salvador]

This patchset makes use of the infrastructure added to meta-freescale
to enable easier use of mainline-based BSP. To enable it, include:

MACHINEOVERRIDES .= ":use-mainline-bsp"

To the local.conf and everything is done automatically.

The bootscript still needs some love to work out of box but this will
be left for Boundary Devices ;-)


Otavio Salvador (4):
  u-boot-script-boundary: Enable 'use-mainline-bsp' support
  nitrogen6x: Use weak-default for virtual/kernel
  nitrogen6x: Add wic image tool support
  nitrogen6x: Add 'use-mainline-bsp' support

 conf/machine/nitrogen6x.conf                     | 21 ++++++++++++++++++++-
 recipes-bsp/u-boot/u-boot-script-boundary_git.bb |  3 ++-
 2 files changed, 22 insertions(+), 2 deletions(-)

-- 
2.12.1

[3rdparty PATCH 1/4] u-boot-script-boundary: Enable 'use-mainline-bsp' support

[Otavio Salvador]

To easy the test with Linux mainline, we are making use of the new
'use-mainline-bsp' override.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
---

 recipes-bsp/u-boot/u-boot-script-boundary_git.bb | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/recipes-bsp/u-boot/u-boot-script-boundary_git.bb b/recipes-bsp/u-boot/u-boot-script-boundary_git.bb
index e4108f9..d3ba7a8 100644
--- a/recipes-bsp/u-boot/u-boot-script-boundary_git.bb
+++ b/recipes-bsp/u-boot/u-boot-script-boundary_git.bb
@@ -12,7 +12,8 @@ S = "${WORKDIR}/git"
 
 inherit deploy
 
-BOOTSCRIPT ?= "${S}/board/boundary/nitrogen6x/6x_bootscript-yocto-3.14.txt"
+BOOTSCRIPT ??= "${S}/board/boundary/nitrogen6x/6x_bootscript-yocto-3.14.txt"
+BOOTSCRIPT_use-mainline-bsp ??= "${S}/board/boundary/nitrogen6x/6x_bootscript-mainline.txt"
 
 UPGRADESCRIPT = "${S}/board/boundary/nitrogen6x/6x_upgrade.txt"
 
-- 
2.12.1

[3rdparty PATCH 2/4] nitrogen6x: Use weak-default for virtual/kernel

[Otavio Salvador]

The virtual/kernel sometimes need to be overriden, adding the
weak-default allow for easier handler of different providers.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
---

 conf/machine/nitrogen6x.conf | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/conf/machine/nitrogen6x.conf b/conf/machine/nitrogen6x.conf
index f9b6cab..f35460d 100644
--- a/conf/machine/nitrogen6x.conf
+++ b/conf/machine/nitrogen6x.conf
@@ -43,7 +43,7 @@ KERNEL_DEVICETREE = "imx6q-sabrelite.dtb \
 KERNEL_IMAGETYPE = "zImage"
 
 PREFERRED_PROVIDER_u-boot = "u-boot-boundary"
-PREFERRED_PROVIDER_virtual/kernel ?= "linux-boundary"
+PREFERRED_PROVIDER_virtual/kernel ??= "linux-boundary"
 
 # Use SPI NOR U-Boot by default
 IMAGE_BOOTLOADER ?= ""
-- 
2.12.1

[3rdparty PATCH 3/4] nitrogen6x: Add wic image tool support

[Otavio Salvador]

The wic image needs to install the bootscript and it loads the
respective kernel image and device-tree files from the image, thus
those need to be included.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
---

 conf/machine/nitrogen6x.conf | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/conf/machine/nitrogen6x.conf b/conf/machine/nitrogen6x.conf
index f35460d..8af1b1f 100644
--- a/conf/machine/nitrogen6x.conf
+++ b/conf/machine/nitrogen6x.conf
@@ -54,10 +54,25 @@ do_rootfs[depends] += "u-boot-script-boundary:do_deploy"
 # Boot scripts to install
 BOOT_SCRIPTS = "6x_bootscript-${MACHINE}:6x_bootscript"
 
+# wic support
+WKS_FILE ?= "sdimage-bootpart.wks"
+IMAGE_BOOT_FILES = " \
+    6x_bootscript-${MACHINE};6x_bootscript \
+    ${KERNEL_IMAGETYPE} \
+    ${KERNEL_IMAGETYPE}-imx6q-sabrelite.dtb;imx6q-sabrelite.dtb \
+    ${KERNEL_IMAGETYPE}-imx6q-nitrogen6_max.dtb;imx6q-nitrogen6_max.dtb ${KERNEL_IMAGETYPE}-imx6qp-nitrogen6_max.dtb;imx6qp-nitrogen6_max.dtb \
+    ${KERNEL_IMAGETYPE}-imx6q-nitrogen6x.dtb;imx6q-nitrogen6x.dtb ${KERNEL_IMAGETYPE}-imx6dl-nitrogen6x.dtb;imx6dl-nitrogen6x.dtb \
+"
+IMAGE_DEPENDS_wic_append = " dosfstools-native mtools-native"
+
 UBOOT_MACHINE ?= "nitrogen6q_config"
 
 SERIAL_CONSOLE = "115200 ttymxc1"
 
 MACHINE_EXTRA_RRECOMMENDS += "linux-firmware-wl12xx"
+MACHINE_ESSENTIAL_EXTRA_RDEPENDS += " \
+    kernel-image \
+    kernel-devicetree \
+"
 
 MACHINE_FEATURES += " pci wifi bluetooth"
-- 
2.12.1

[3rdparty PATCH 4/4] nitrogen6x: Add 'use-mainline-bsp' support

[Otavio Salvador]

The 'use-mainline-bsp' makes use of linux-fslc as kernel and removes
the not yet supported device-tree files from installation set.

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
---

 conf/machine/nitrogen6x.conf | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/conf/machine/nitrogen6x.conf b/conf/machine/nitrogen6x.conf
index 8af1b1f..aa068ac 100644
--- a/conf/machine/nitrogen6x.conf
+++ b/conf/machine/nitrogen6x.conf
@@ -40,10 +40,14 @@ KERNEL_DEVICETREE = "imx6q-sabrelite.dtb \
                         imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
                         imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb \
 "
+KERNEL_DEVICETREE_remove_use-mainline-bsp = "imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
+                                             imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb"
+
 KERNEL_IMAGETYPE = "zImage"
 
 PREFERRED_PROVIDER_u-boot = "u-boot-boundary"
 PREFERRED_PROVIDER_virtual/kernel ??= "linux-boundary"
+PREFERRED_PROVIDER_virtual/kernel_use-mainline-bsp ??= "linux-fslc"
 
 # Use SPI NOR U-Boot by default
 IMAGE_BOOTLOADER ?= ""
-- 
2.12.1

Re: [3rdparty PATCH 0/4] Allow easier use of mainline-based BSP on i.MX products (Nitrogen6x support)

[Gary Bisson]

Hi Otavio,

First of all, thank you for this series and the great job you've done to
add mainline support, this is highly appreciated!

On Fri, Mar 24, 2017 at 05:12:12PM -0300, Otavio Salvador wrote:
> 
> This patchset makes use of the infrastructure added to meta-freescale
> to enable easier use of mainline-based BSP. To enable it, include:
> 
> MACHINEOVERRIDES .= ":use-mainline-bsp"
> 
> To the local.conf and everything is done automatically.
> 
> The bootscript still needs some love to work out of box but this will
> be left for Boundary Devices ;-)

I've fixed one of the two issues already [1] so bootdir doesn't need to
be set any more.

The only thing that still needs to be figured out is the root= parameter
which right now requires the following variable to be set when booting a
Nitrogen6X with WiFi module from first SD slot:
=> setenv root /dev/mmcblk1p2

The reason is that mainline kernel doesn't allow to change the numbering
order of SDHC devices based on aliases. Sascha offered a patch which
never got accepted (but is in the NXP tree) [2].

So on a device where a WiFi module is present, the first sdcard device
will be named mmcblk1. But on a SabreLite (no WiFi), it will be mmcblk0
as the bootscript thinks it is.

I haven't found a good approach yet to fix it, ideas are welcomed ;)

Regards,
Gary

[1] https://github.com/boundarydevices/u-boot-imx6/commit/bc55c1e2
[2] https://patchwork.kernel.org/patch/4223911/

Re: [3rdparty PATCH 1/4] u-boot-script-boundary: Enable 'use-mainline-bsp' support

[Gary Bisson]

Hi Otavio,

On Fri, Mar 24, 2017 at 05:12:13PM -0300, Otavio Salvador wrote:
> To easy the test with Linux mainline, we are making use of the new
> 'use-mainline-bsp' override.
> 
> Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>

Looks good.

Reviewed-by: Gary Bisson <gary.bisson@boundarydevices.com>

Regards,
Gary

Re: [3rdparty PATCH 2/4] nitrogen6x: Use weak-default for virtual/kernel

[Gary Bisson]

Hi Otavio,

On Fri, Mar 24, 2017 at 05:12:14PM -0300, Otavio Salvador wrote:
> The virtual/kernel sometimes need to be overriden, adding the
> weak-default allow for easier handler of different providers.
> 
> Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
> ---
> 
>  conf/machine/nitrogen6x.conf | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/conf/machine/nitrogen6x.conf b/conf/machine/nitrogen6x.conf
> index f9b6cab..f35460d 100644
> --- a/conf/machine/nitrogen6x.conf
> +++ b/conf/machine/nitrogen6x.conf
> @@ -43,7 +43,7 @@ KERNEL_DEVICETREE = "imx6q-sabrelite.dtb \
>  KERNEL_IMAGETYPE = "zImage"
>  
>  PREFERRED_PROVIDER_u-boot = "u-boot-boundary"
> -PREFERRED_PROVIDER_virtual/kernel ?= "linux-boundary"
> +PREFERRED_PROVIDER_virtual/kernel ??= "linux-boundary"
>  
>  # Use SPI NOR U-Boot by default
>  IMAGE_BOOTLOADER ?= ""
> -- 
> 2.12.1

Same here, looks good.

Reviewed-by: Gary Bisson <gary.bisson@boundarydevices.com>

Regards,
Gary

Re: [3rdparty PATCH 3/4] nitrogen6x: Add wic image tool support

[Gary Bisson]

Hi Otavio,

On Fri, Mar 24, 2017 at 05:12:15PM -0300, Otavio Salvador wrote:
> The wic image needs to install the bootscript and it loads the
> respective kernel image and device-tree files from the image, thus
> those need to be included.

Not sure to understand the wic image requirement. First, is the wic
image only applies when "use-mainline-bsp" is set? I couldn't find where
it was mainline specific.

Regards,
Gary

Re: [3rdparty PATCH 4/4] nitrogen6x: Add 'use-mainline-bsp' support

[Gary Bisson]

Hi Otavio,

On Fri, Mar 24, 2017 at 05:12:16PM -0300, Otavio Salvador wrote:
> The 'use-mainline-bsp' makes use of linux-fslc as kernel and removes
> the not yet supported device-tree files from installation set.
> 
> Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
> ---
> 
>  conf/machine/nitrogen6x.conf | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/conf/machine/nitrogen6x.conf b/conf/machine/nitrogen6x.conf
> index 8af1b1f..aa068ac 100644
> --- a/conf/machine/nitrogen6x.conf
> +++ b/conf/machine/nitrogen6x.conf
> @@ -40,10 +40,14 @@ KERNEL_DEVICETREE = "imx6q-sabrelite.dtb \
>                          imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
>                          imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb \
>  "
> +KERNEL_DEVICETREE_remove_use-mainline-bsp = "imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
> +                                             imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb"
> +

Why do you remove the imx6q-nitrogen6_som2 whereas it is now in
linux-fslc (and in 4.10)?

Regards,
Gary

Re: [3rdparty PATCH 3/4] nitrogen6x: Add wic image tool support

[Otavio Salvador]

On Sat, Mar 25, 2017 at 3:12 PM, Gary Bisson
<gary.bisson@boundarydevices.com> wrote:
> On Fri, Mar 24, 2017 at 05:12:15PM -0300, Otavio Salvador wrote:
>> The wic image needs to install the bootscript and it loads the
>> respective kernel image and device-tree files from the image, thus
>> those need to be included.
>
> Not sure to understand the wic image requirement. First, is the wic
> image only applies when "use-mainline-bsp" is set? I couldn't find where
> it was mainline specific.

It is not mainline specific but as we move away the mx6 override the
image class does not work. So I end using it so we can get it building
an out of box image to use.

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750

Re: [3rdparty PATCH 4/4] nitrogen6x: Add 'use-mainline-bsp' support

[Otavio Salvador]

On Sat, Mar 25, 2017 at 3:13 PM, Gary Bisson
<gary.bisson@boundarydevices.com> wrote:
> On Fri, Mar 24, 2017 at 05:12:16PM -0300, Otavio Salvador wrote:
>> The 'use-mainline-bsp' makes use of linux-fslc as kernel and removes
>> the not yet supported device-tree files from installation set.
>>
>> Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
>> ---
>>
>>  conf/machine/nitrogen6x.conf | 4 ++++
>>  1 file changed, 4 insertions(+)
>>
>> diff --git a/conf/machine/nitrogen6x.conf b/conf/machine/nitrogen6x.conf
>> index 8af1b1f..aa068ac 100644
>> --- a/conf/machine/nitrogen6x.conf
>> +++ b/conf/machine/nitrogen6x.conf
>> @@ -40,10 +40,14 @@ KERNEL_DEVICETREE = "imx6q-sabrelite.dtb \
>>                          imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
>>                          imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb \
>>  "
>> +KERNEL_DEVICETREE_remove_use-mainline-bsp = "imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
>> +                                             imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb"
>> +
>
> Why do you remove the imx6q-nitrogen6_som2 whereas it is now in
> linux-fslc (and in 4.10)?

We are still using 4.9 so it does not provide som2. If you can add it, good.

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750

Re: [3rdparty PATCH 4/4] nitrogen6x: Add 'use-mainline-bsp' support

[Gary Bisson]

Hi Otavio,

On Sun, Mar 26, 2017 at 8:38 PM, Otavio Salvador
<otavio.salvador@ossystems.com.br> wrote:
>
> On Sat, Mar 25, 2017 at 3:13 PM, Gary Bisson
> <gary.bisson@boundarydevices.com> wrote:
> > On Fri, Mar 24, 2017 at 05:12:16PM -0300, Otavio Salvador wrote:
> >> The 'use-mainline-bsp' makes use of linux-fslc as kernel and removes
> >> the not yet supported device-tree files from installation set.
> >>
> >> Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
> >> ---
> >>
> >>  conf/machine/nitrogen6x.conf | 4 ++++
> >>  1 file changed, 4 insertions(+)
> >>
> >> diff --git a/conf/machine/nitrogen6x.conf b/conf/machine/nitrogen6x.conf
> >> index 8af1b1f..aa068ac 100644
> >> --- a/conf/machine/nitrogen6x.conf
> >> +++ b/conf/machine/nitrogen6x.conf
> >> @@ -40,10 +40,14 @@ KERNEL_DEVICETREE = "imx6q-sabrelite.dtb \
> >>                          imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
> >>                          imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb \
> >>  "
> >> +KERNEL_DEVICETREE_remove_use-mainline-bsp = "imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
> >> +                                             imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb"
> >> +
> >
> > Why do you remove the imx6q-nitrogen6_som2 whereas it is now in
> > linux-fslc (and in 4.10)?
>
> We are still using 4.9 so it does not provide som2. If you can add it, good.

It is already part of linux-fslc:
https://github.com/Freescale/linux-fslc/commit/404a65b0

Regards,
Gary

Re: [3rdparty PATCH 0/4] Allow easier use of mainline-based BSP on i.MX products (Nitrogen6x support)

[Otavio Salvador]

On Sat, Mar 25, 2017 at 3:03 PM, Gary Bisson
<gary.bisson@boundarydevices.com> wrote:
> First of all, thank you for this series and the great job you've done to
> add mainline support, this is highly appreciated!

This was indeed an important step. It makes easier to compare both BSP
support now.

> On Fri, Mar 24, 2017 at 05:12:12PM -0300, Otavio Salvador wrote:
>>
>> This patchset makes use of the infrastructure added to meta-freescale
>> to enable easier use of mainline-based BSP. To enable it, include:
>>
>> MACHINEOVERRIDES .= ":use-mainline-bsp"
>>
>> To the local.conf and everything is done automatically.
>>
>> The bootscript still needs some love to work out of box but this will
>> be left for Boundary Devices ;-)
>
> I've fixed one of the two issues already [1] so bootdir doesn't need to
> be set any more.

Great.

> The only thing that still needs to be figured out is the root= parameter
> which right now requires the following variable to be set when booting a
> Nitrogen6X with WiFi module from first SD slot:
> => setenv root /dev/mmcblk1p2
>
> The reason is that mainline kernel doesn't allow to change the numbering
> order of SDHC devices based on aliases. Sascha offered a patch which
> never got accepted (but is in the NXP tree) [2].
>
> So on a device where a WiFi module is present, the first sdcard device
> will be named mmcblk1. But on a SabreLite (no WiFi), it will be mmcblk0
> as the bootscript thinks it is.
>
> I haven't found a good approach yet to fix it, ideas are welcomed ;)

Use UUID for booting. It can be done on U-Boot as it can pass the UUID
for the root= argument. See:

https://github.com/Freescale/u-boot-fslc/commit/b4227954508ac995e9ded35ea055456788a2e807

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750

Re: [3rdparty PATCH 4/4] nitrogen6x: Add 'use-mainline-bsp' support

[Otavio Salvador]

On Sun, Mar 26, 2017 at 3:46 PM, Gary Bisson
<gary.bisson@boundarydevices.com> wrote:
> Hi Otavio,
>
> On Sun, Mar 26, 2017 at 8:38 PM, Otavio Salvador
> <otavio.salvador@ossystems.com.br> wrote:
>>
>> On Sat, Mar 25, 2017 at 3:13 PM, Gary Bisson
>> <gary.bisson@boundarydevices.com> wrote:
>> > On Fri, Mar 24, 2017 at 05:12:16PM -0300, Otavio Salvador wrote:
>> >> The 'use-mainline-bsp' makes use of linux-fslc as kernel and removes
>> >> the not yet supported device-tree files from installation set.
>> >>
>> >> Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
>> >> ---
>> >>
>> >>  conf/machine/nitrogen6x.conf | 4 ++++
>> >>  1 file changed, 4 insertions(+)
>> >>
>> >> diff --git a/conf/machine/nitrogen6x.conf b/conf/machine/nitrogen6x.conf
>> >> index 8af1b1f..aa068ac 100644
>> >> --- a/conf/machine/nitrogen6x.conf
>> >> +++ b/conf/machine/nitrogen6x.conf
>> >> @@ -40,10 +40,14 @@ KERNEL_DEVICETREE = "imx6q-sabrelite.dtb \
>> >>                          imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
>> >>                          imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb \
>> >>  "
>> >> +KERNEL_DEVICETREE_remove_use-mainline-bsp = "imx6q-nitrogen6_som2.dtb imx6qp-nitrogen6_som2.dtb \
>> >> +                                             imx6dl-nitrogen6_vm.dtb imx6dl-nitrogen6_vm-magstripe.dtb"
>> >> +
>> >
>> > Why do you remove the imx6q-nitrogen6_som2 whereas it is now in
>> > linux-fslc (and in 4.10)?
>>
>> We are still using 4.9 so it does not provide som2. If you can add it, good.
>
> It is already part of linux-fslc:
> https://github.com/Freescale/linux-fslc/commit/404a65b0

Oh indeed; I got it before picking those commits. Thanks for reminding me.

-- 
Otavio Salvador                             O.S. Systems
http://www.ossystems.com.br        http://code.ossystems.com.br
Mobile: +55 (53) 9981-7854            Mobile: +1 (347) 903-9750

Re: [3rdparty PATCH 3/4] nitrogen6x: Add wic image tool support

[Gary Bisson]

On Sun, Mar 26, 2017 at 8:37 PM, Otavio Salvador
<otavio.salvador@ossystems.com.br> wrote:
> On Sat, Mar 25, 2017 at 3:12 PM, Gary Bisson
> <gary.bisson@boundarydevices.com> wrote:
>> On Fri, Mar 24, 2017 at 05:12:15PM -0300, Otavio Salvador wrote:
>>> The wic image needs to install the bootscript and it loads the
>>> respective kernel image and device-tree files from the image, thus
>>> those need to be included.
>>
>> Not sure to understand the wic image requirement. First, is the wic
>> image only applies when "use-mainline-bsp" is set? I couldn't find where
>> it was mainline specific.
>
> It is not mainline specific but as we move away the mx6 override the
> image class does not work. So I end using it so we can get it building
> an out of box image to use.

Ok good to know. I just wanted to check that the other dtb shouldn't
be declared as well for "regular" NXP-based BSP.

In that case:
Reviewed-by: Gary Bisson <gary.bisson@boundarydevices.com>

Regards,
Gary

Re: [3rdparty PATCH 0/4] Allow easier use of mainline-based BSP on i.MX products (Nitrogen6x support)

[Gary Bisson]

Hi Otavio,

On Sun, Mar 26, 2017 at 8:54 PM, Otavio Salvador
<otavio.salvador@ossystems.com.br> wrote:
> <snip>
>> The only thing that still needs to be figured out is the root= parameter
>> which right now requires the following variable to be set when booting a
>> Nitrogen6X with WiFi module from first SD slot:
>> => setenv root /dev/mmcblk1p2
>>
>> The reason is that mainline kernel doesn't allow to change the numbering
>> order of SDHC devices based on aliases. Sascha offered a patch which
>> never got accepted (but is in the NXP tree) [2].
>>
>> So on a device where a WiFi module is present, the first sdcard device
>> will be named mmcblk1. But on a SabreLite (no WiFi), it will be mmcblk0
>> as the bootscript thinks it is.
>>
>> I haven't found a good approach yet to fix it, ideas are welcomed ;)
>
> Use UUID for booting. It can be done on U-Boot as it can pass the UUID
> for the root= argument. See:

Great idea! I'm going to do that, I need to add the CMD_PART to our
config and update the 6x_bootscript accordingly.

I'll let you know once it's done (hopefully I'll have time this week).

Regards,
Gary