[meta-ti][PATCH 0/1 v2] Add recipes to build initramfs image

[meta-ti][PATCH 0/1 v2] Add recipes to build initramfs image

[Moteen Shah]

The patch aims to add a new recipe which will package
boot essential and some other modules in image which
can later be used in the boot process of all K3 platforms. 

The motivation behind the work is to probe modules(in boot time)
which could not be built in the upstream Linux kernel image, as
using it as inbuilt drivers will increase the kernel image size, 
which is undesirable by the upstream folks.

Hence, build those drivers as modules and package it inside initramfs
and later get it probed through initramfs-udev(device manager).

Changes since v1: 
- Migrate the recipe to meta-ti so that it can be used in upstream
testing

Link to V1: https://lists.yoctoproject.org/g/meta-arago/message/16515

Moteen Shah (1):
  recipes-ti: initramfs: Make minimal initrd image

 .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
 .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
 create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb

-- 
2.34.1

[meta-ti][PATCH 1/1 v2] recipes-ti: initramfs: Make minimal initrd image

[Moteen Shah]

Add recipes to make initramfs image based on systemd.
The image will package boot essential and other modules
which will be modprobed by initramfs udev once the inbuilt
drivers gets probed.

Signed-off-by: Moteen Shah <m-shah@ti.com>
---
 .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
 .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
 2 files changed, 54 insertions(+)
 create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
 create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb

diff --git a/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
new file mode 100644
index 00000000..5d2ff390
--- /dev/null
+++ b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
@@ -0,0 +1,5 @@
+SUMMARY = "Minimal initramfs for boot requirements"
+
+require recipes-core/packagegroups/packagegroup-core-boot.bb
+
+RDEPENDS:${PN}:remove = "grub-efi kernel"
diff --git a/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
new file mode 100644
index 00000000..4cebf595
--- /dev/null
+++ b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
@@ -0,0 +1,49 @@
+SUMMARY = "TI SDK super minimal base image for initramfs"
+
+DESCRIPTION = "Image meant for basic boot of linux kernel. Intended as\
+ bare system, this image does not package the kernel in the\
+ standard /boot folder in rootfs. Instead, it provides a base\
+ rootfs allowing kernel to be deployed elsewhere\
+ (tftp/separate boot partition/jtag log etc..) and boot\
+ the image.\
+"
+
+LICENSE = "MIT"
+
+inherit core-image
+
+IMAGE_FEATURES:remove = "package-management"
+
+INITRAMFS_FSTYPES = "cpio cpio.xz"
+
+#INITRAMFS_MAXSIZE = "65536"
+#IMAGE_OVERHEAD_FACTOR = "1"
+
+IMAGE_FSTYPES = "${INITRAMFS_FSTYPES}"
+
+INITRAMFS_SCRIPTS ?= "initramfs-framework-base initramfs-module-udev initramfs-module-nfsrootfs"
+
+MODULES = "\
+    kernel-module-cdns-pltfrm \
+    kernel-module-ti-j721e-ufs \
+    kernel-module-tps6594-i2c \
+"
+
+UTILS = "\
+    cifs-utils \
+    nfs-utils \
+    nfs-utils-client \
+"
+
+PACKAGE_INSTALL = "${INITRAMFS_SCRIPTS} ${UTILS} ${MODULES} packagegroup-ti-initramfs "
+
+export IMAGE_BASENAME = "ti-tiny-initramfs"
+
+# To further reduce the size of the rootfs, remove the /boot directory from
+# the final image this is usually done by adding RDEPENDS_kernel-base = ""
+# in the configuration file. In our case we can't use this method. Instead we
+# just wipe out the content of "/boot" before creating the image.
+ROOTFS_POSTPROCESS_COMMAND += "empty_boot_dir; "
+empty_boot_dir () {
+	rm -rf ${IMAGE_ROOTFS}/boot/*
+}
-- 
2.34.1

Re: [meta-ti][PATCH 1/1 v2] recipes-ti: initramfs: Make minimal initrd image

[Anshul Dalal]

Hi Moteen,

On Thu Sep 4, 2025 at 6:13 PM IST, Moteen Shah wrote:
> Add recipes to make initramfs image based on systemd.
> The image will package boot essential and other modules
> which will be modprobed by initramfs udev once the inbuilt
> drivers gets probed.
>
> Signed-off-by: Moteen Shah <m-shah@ti.com>
> ---
>  .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
>  .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
>  2 files changed, 54 insertions(+)
>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>
> diff --git a/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> new file mode 100644
> index 00000000..5d2ff390
> --- /dev/null
> +++ b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> @@ -0,0 +1,5 @@
> +SUMMARY = "Minimal initramfs for boot requirements"
> +
> +require recipes-core/packagegroups/packagegroup-core-boot.bb
> +
> +RDEPENDS:${PN}:remove = "grub-efi kernel"
> diff --git a/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> new file mode 100644
> index 00000000..4cebf595
> --- /dev/null
> +++ b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> @@ -0,0 +1,49 @@
> +SUMMARY = "TI SDK super minimal base image for initramfs"
> +
> +DESCRIPTION = "Image meant for basic boot of linux kernel. Intended as\
> + bare system, this image does not package the kernel in the\
> + standard /boot folder in rootfs. Instead, it provides a base\
> + rootfs allowing kernel to be deployed elsewhere\
> + (tftp/separate boot partition/jtag log etc..) and boot\
> + the image.\
> +"
> +
> +LICENSE = "MIT"
> +
> +inherit core-image
> +
> +IMAGE_FEATURES:remove = "package-management"
> +
> +INITRAMFS_FSTYPES = "cpio cpio.xz"
> +
> +#INITRAMFS_MAXSIZE = "65536"
> +#IMAGE_OVERHEAD_FACTOR = "1"
> +

Why are these two commented out?

Regards,
Anshul

Re: [meta-ti][PATCH 1/1 v2] recipes-ti: initramfs: Make minimal initrd image

[Bryan Brattlof]

On September  4, 2025 thus sayeth Moteen Shah:
> Add recipes to make initramfs image based on systemd.
> The image will package boot essential and other modules
> which will be modprobed by initramfs udev once the inbuilt
> drivers gets probed.
> 
> Signed-off-by: Moteen Shah <m-shah@ti.com>
> ---
>  .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
>  .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
>  2 files changed, 54 insertions(+)
>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> 
> diff --git a/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> new file mode 100644
> index 00000000..5d2ff390
> --- /dev/null
> +++ b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> @@ -0,0 +1,5 @@
> +SUMMARY = "Minimal initramfs for boot requirements"
> +
> +require recipes-core/packagegroups/packagegroup-core-boot.bb
> +
> +RDEPENDS:${PN}:remove = "grub-efi kernel"
> diff --git a/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> new file mode 100644
> index 00000000..4cebf595
> --- /dev/null
> +++ b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> @@ -0,0 +1,49 @@
> +SUMMARY = "TI SDK super minimal base image for initramfs"
> +
> +DESCRIPTION = "Image meant for basic boot of linux kernel. Intended as\
> + bare system, this image does not package the kernel in the\
> + standard /boot folder in rootfs. Instead, it provides a base\
> + rootfs allowing kernel to be deployed elsewhere\
> + (tftp/separate boot partition/jtag log etc..) and boot\
> + the image.\
> +"
> +
> +LICENSE = "MIT"
> +
> +inherit core-image
> +
> +IMAGE_FEATURES:remove = "package-management"
> +
> +INITRAMFS_FSTYPES = "cpio cpio.xz"
> +
> +#INITRAMFS_MAXSIZE = "65536"
> +#IMAGE_OVERHEAD_FACTOR = "1"
> +
> +IMAGE_FSTYPES = "${INITRAMFS_FSTYPES}"
> +
> +INITRAMFS_SCRIPTS ?= "initramfs-framework-base initramfs-module-udev initramfs-module-nfsrootfs"
> +
> +MODULES = "\
> +    kernel-module-cdns-pltfrm \
> +    kernel-module-ti-j721e-ufs \
> +    kernel-module-tps6594-i2c \
> +"

Are these all the modules we'll need? Is everything else build-in the 
default defconfig? or are we expecting this list to expand as more 
platforms start migrating to this?

~Bryan

Re: [meta-arago] [meta-ti][PATCH 1/1 v2] recipes-ti: initramfs: Make minimal initrd image

[Randolph Sapp]

On Tue Sep 9, 2025 at 9:56 AM CDT, Bryan Brattlof via lists.yoctoproject.org wrote:
> On September  4, 2025 thus sayeth Moteen Shah:
>> Add recipes to make initramfs image based on systemd.
>> The image will package boot essential and other modules
>> which will be modprobed by initramfs udev once the inbuilt
>> drivers gets probed.
>> 
>> Signed-off-by: Moteen Shah <m-shah@ti.com>
>> ---
>>  .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
>>  .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
>>  2 files changed, 54 insertions(+)
>>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>> 
>> diff --git a/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>> new file mode 100644
>> index 00000000..5d2ff390
>> --- /dev/null
>> +++ b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>> @@ -0,0 +1,5 @@
>> +SUMMARY = "Minimal initramfs for boot requirements"
>> +
>> +require recipes-core/packagegroups/packagegroup-core-boot.bb
>> +
>> +RDEPENDS:${PN}:remove = "grub-efi kernel"
>> diff --git a/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>> new file mode 100644
>> index 00000000..4cebf595
>> --- /dev/null
>> +++ b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>> @@ -0,0 +1,49 @@
>> +SUMMARY = "TI SDK super minimal base image for initramfs"
>> +
>> +DESCRIPTION = "Image meant for basic boot of linux kernel. Intended as\
>> + bare system, this image does not package the kernel in the\
>> + standard /boot folder in rootfs. Instead, it provides a base\
>> + rootfs allowing kernel to be deployed elsewhere\
>> + (tftp/separate boot partition/jtag log etc..) and boot\
>> + the image.\
>> +"
>> +
>> +LICENSE = "MIT"
>> +
>> +inherit core-image
>> +
>> +IMAGE_FEATURES:remove = "package-management"
>> +
>> +INITRAMFS_FSTYPES = "cpio cpio.xz"
>> +
>> +#INITRAMFS_MAXSIZE = "65536"
>> +#IMAGE_OVERHEAD_FACTOR = "1"
>> +
>> +IMAGE_FSTYPES = "${INITRAMFS_FSTYPES}"
>> +
>> +INITRAMFS_SCRIPTS ?= "initramfs-framework-base initramfs-module-udev initramfs-module-nfsrootfs"
>> +
>> +MODULES = "\
>> +    kernel-module-cdns-pltfrm \
>> +    kernel-module-ti-j721e-ufs \
>> +    kernel-module-tps6594-i2c \
>> +"
>
> Are these all the modules we'll need? Is everything else build-in the 
> default defconfig? or are we expecting this list to expand as more 
> platforms start migrating to this?
>
> ~Bryan

Should this instead be defined per machine with
MACHINE_ESSENTIAL_EXTRA_RDEPENDS?

https://docs.yoctoproject.org/ref-manual/variables.html#term-MACHINE_ESSENTIAL_EXTRA_RDEPENDS

Re: [meta-arago] [meta-ti][PATCH 1/1 v2] recipes-ti: initramfs: Make minimal initrd image

[Bryan Brattlof]

On September  9, 2025 thus sayeth Randolph Sapp:
> On Tue Sep 9, 2025 at 9:56 AM CDT, Bryan Brattlof via lists.yoctoproject.org wrote:
> > On September  4, 2025 thus sayeth Moteen Shah:
> >> Add recipes to make initramfs image based on systemd.
> >> The image will package boot essential and other modules
> >> which will be modprobed by initramfs udev once the inbuilt
> >> drivers gets probed.
> >> 
> >> Signed-off-by: Moteen Shah <m-shah@ti.com>
> >> ---
> >>  .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
> >>  .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
> >>  2 files changed, 54 insertions(+)
> >>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> >>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> >> 
> >> diff --git a/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> >> new file mode 100644
> >> index 00000000..5d2ff390
> >> --- /dev/null
> >> +++ b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> >> @@ -0,0 +1,5 @@
> >> +SUMMARY = "Minimal initramfs for boot requirements"
> >> +
> >> +require recipes-core/packagegroups/packagegroup-core-boot.bb
> >> +
> >> +RDEPENDS:${PN}:remove = "grub-efi kernel"
> >> diff --git a/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> >> new file mode 100644
> >> index 00000000..4cebf595
> >> --- /dev/null
> >> +++ b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> >> @@ -0,0 +1,49 @@
> >> +SUMMARY = "TI SDK super minimal base image for initramfs"
> >> +
> >> +DESCRIPTION = "Image meant for basic boot of linux kernel. Intended as\
> >> + bare system, this image does not package the kernel in the\
> >> + standard /boot folder in rootfs. Instead, it provides a base\
> >> + rootfs allowing kernel to be deployed elsewhere\
> >> + (tftp/separate boot partition/jtag log etc..) and boot\
> >> + the image.\
> >> +"
> >> +
> >> +LICENSE = "MIT"
> >> +
> >> +inherit core-image
> >> +
> >> +IMAGE_FEATURES:remove = "package-management"
> >> +
> >> +INITRAMFS_FSTYPES = "cpio cpio.xz"
> >> +
> >> +#INITRAMFS_MAXSIZE = "65536"
> >> +#IMAGE_OVERHEAD_FACTOR = "1"
> >> +
> >> +IMAGE_FSTYPES = "${INITRAMFS_FSTYPES}"
> >> +
> >> +INITRAMFS_SCRIPTS ?= "initramfs-framework-base initramfs-module-udev initramfs-module-nfsrootfs"
> >> +
> >> +MODULES = "\
> >> +    kernel-module-cdns-pltfrm \
> >> +    kernel-module-ti-j721e-ufs \
> >> +    kernel-module-tps6594-i2c \
> >> +"
> >
> > Are these all the modules we'll need? Is everything else build-in the 
> > default defconfig? or are we expecting this list to expand as more 
> > platforms start migrating to this?
> >
> > ~Bryan
> 
> Should this instead be defined per machine with
> MACHINE_ESSENTIAL_EXTRA_RDEPENDS?
> 
> https://docs.yoctoproject.org/ref-manual/variables.html#term-MACHINE_ESSENTIAL_EXTRA_RDEPENDS

Yeah, I guess what I'm slowly realizing is we're adding roughly a 140MB 
binary to the critical path for the bootloaders (so long any boot KPI) 
all so we can have a PMIC driver as a builtin.

All the distributions I can think of all modify the ARM64 defconfig in 
some way to better suit their distribution. Yocto even has the advantage 
of knowing what target they are building for. Should we instead carry a 
fragment, or use some other mechanism, to change the kernel's config so 
the PMIC driver is a builtin if needed by the target?

~Bryan

Re: [meta-arago] [meta-ti][PATCH 1/1 v2] recipes-ti: initramfs: Make minimal initrd image

[Randolph Sapp]

On Wed Sep 10, 2025 at 6:48 AM CDT, Bryan Brattlof wrote:
> On September  9, 2025 thus sayeth Randolph Sapp:
>> On Tue Sep 9, 2025 at 9:56 AM CDT, Bryan Brattlof via lists.yoctoproject.org wrote:
>> > On September  4, 2025 thus sayeth Moteen Shah:
>> >> Add recipes to make initramfs image based on systemd.
>> >> The image will package boot essential and other modules
>> >> which will be modprobed by initramfs udev once the inbuilt
>> >> drivers gets probed.
>> >> 
>> >> Signed-off-by: Moteen Shah <m-shah@ti.com>
>> >> ---
>> >>  .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
>> >>  .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
>> >>  2 files changed, 54 insertions(+)
>> >>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>> >>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>> >> 
>> >> diff --git a/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>> >> new file mode 100644
>> >> index 00000000..5d2ff390
>> >> --- /dev/null
>> >> +++ b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>> >> @@ -0,0 +1,5 @@
>> >> +SUMMARY = "Minimal initramfs for boot requirements"
>> >> +
>> >> +require recipes-core/packagegroups/packagegroup-core-boot.bb
>> >> +
>> >> +RDEPENDS:${PN}:remove = "grub-efi kernel"
>> >> diff --git a/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>> >> new file mode 100644
>> >> index 00000000..4cebf595
>> >> --- /dev/null
>> >> +++ b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>> >> @@ -0,0 +1,49 @@
>> >> +SUMMARY = "TI SDK super minimal base image for initramfs"
>> >> +
>> >> +DESCRIPTION = "Image meant for basic boot of linux kernel. Intended as\
>> >> + bare system, this image does not package the kernel in the\
>> >> + standard /boot folder in rootfs. Instead, it provides a base\
>> >> + rootfs allowing kernel to be deployed elsewhere\
>> >> + (tftp/separate boot partition/jtag log etc..) and boot\
>> >> + the image.\
>> >> +"
>> >> +
>> >> +LICENSE = "MIT"
>> >> +
>> >> +inherit core-image
>> >> +
>> >> +IMAGE_FEATURES:remove = "package-management"
>> >> +
>> >> +INITRAMFS_FSTYPES = "cpio cpio.xz"
>> >> +
>> >> +#INITRAMFS_MAXSIZE = "65536"
>> >> +#IMAGE_OVERHEAD_FACTOR = "1"
>> >> +
>> >> +IMAGE_FSTYPES = "${INITRAMFS_FSTYPES}"
>> >> +
>> >> +INITRAMFS_SCRIPTS ?= "initramfs-framework-base initramfs-module-udev initramfs-module-nfsrootfs"
>> >> +
>> >> +MODULES = "\
>> >> +    kernel-module-cdns-pltfrm \
>> >> +    kernel-module-ti-j721e-ufs \
>> >> +    kernel-module-tps6594-i2c \
>> >> +"
>> >
>> > Are these all the modules we'll need? Is everything else build-in the 
>> > default defconfig? or are we expecting this list to expand as more 
>> > platforms start migrating to this?
>> >
>> > ~Bryan
>> 
>> Should this instead be defined per machine with
>> MACHINE_ESSENTIAL_EXTRA_RDEPENDS?
>> 
>> https://docs.yoctoproject.org/ref-manual/variables.html#term-MACHINE_ESSENTIAL_EXTRA_RDEPENDS
>
> Yeah, I guess what I'm slowly realizing is we're adding roughly a 140MB 
> binary to the critical path for the bootloaders (so long any boot KPI) 
> all so we can have a PMIC driver as a builtin.
>
> All the distributions I can think of all modify the ARM64 defconfig in 
> some way to better suit their distribution. Yocto even has the advantage 
> of knowing what target they are building for. Should we instead carry a 
> fragment, or use some other mechanism, to change the kernel's config so 
> the PMIC driver is a builtin if needed by the target?
>
> ~Bryan

Use of conditional configs is simply reverting back to the schemes we were using
3+ years ago. Initramfs is big and slow, but it's standard and can be leveraged
across other distros easily as it's already been a production solution for them
for quite some time.

That being said, Yocto is *unique*, and what it doesn't do weird itself, it
leaves for the implementer to make weird in their own way. I guess it doesn't
really matter if we don't care about having a uniform bootflow across distros,
but that sounds like hell.

- Randolph

Re: [meta-arago] [meta-ti][PATCH 1/1 v2] recipes-ti: initramfs: Make minimal initrd image

[Bryan Brattlof]

On September 10, 2025 thus sayeth Randolph Sapp:
> On Wed Sep 10, 2025 at 6:48 AM CDT, Bryan Brattlof wrote:
> > On September  9, 2025 thus sayeth Randolph Sapp:
> >> On Tue Sep 9, 2025 at 9:56 AM CDT, Bryan Brattlof via lists.yoctoproject.org wrote:
> >> > On September  4, 2025 thus sayeth Moteen Shah:
> >> >> Add recipes to make initramfs image based on systemd.
> >> >> The image will package boot essential and other modules
> >> >> which will be modprobed by initramfs udev once the inbuilt
> >> >> drivers gets probed.
> >> >> 
> >> >> Signed-off-by: Moteen Shah <m-shah@ti.com>
> >> >> ---
> >> >>  .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
> >> >>  .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
> >> >>  2 files changed, 54 insertions(+)
> >> >>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> >> >>  create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> >> >> 
> >> >> diff --git a/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> >> >> new file mode 100644
> >> >> index 00000000..5d2ff390
> >> >> --- /dev/null
> >> >> +++ b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
> >> >> @@ -0,0 +1,5 @@
> >> >> +SUMMARY = "Minimal initramfs for boot requirements"
> >> >> +
> >> >> +require recipes-core/packagegroups/packagegroup-core-boot.bb
> >> >> +
> >> >> +RDEPENDS:${PN}:remove = "grub-efi kernel"
> >> >> diff --git a/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> >> >> new file mode 100644
> >> >> index 00000000..4cebf595
> >> >> --- /dev/null
> >> >> +++ b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
> >> >> @@ -0,0 +1,49 @@
> >> >> +SUMMARY = "TI SDK super minimal base image for initramfs"
> >> >> +
> >> >> +DESCRIPTION = "Image meant for basic boot of linux kernel. Intended as\
> >> >> + bare system, this image does not package the kernel in the\
> >> >> + standard /boot folder in rootfs. Instead, it provides a base\
> >> >> + rootfs allowing kernel to be deployed elsewhere\
> >> >> + (tftp/separate boot partition/jtag log etc..) and boot\
> >> >> + the image.\
> >> >> +"
> >> >> +
> >> >> +LICENSE = "MIT"
> >> >> +
> >> >> +inherit core-image
> >> >> +
> >> >> +IMAGE_FEATURES:remove = "package-management"
> >> >> +
> >> >> +INITRAMFS_FSTYPES = "cpio cpio.xz"
> >> >> +
> >> >> +#INITRAMFS_MAXSIZE = "65536"
> >> >> +#IMAGE_OVERHEAD_FACTOR = "1"
> >> >> +
> >> >> +IMAGE_FSTYPES = "${INITRAMFS_FSTYPES}"
> >> >> +
> >> >> +INITRAMFS_SCRIPTS ?= "initramfs-framework-base initramfs-module-udev initramfs-module-nfsrootfs"
> >> >> +
> >> >> +MODULES = "\
> >> >> +    kernel-module-cdns-pltfrm \
> >> >> +    kernel-module-ti-j721e-ufs \
> >> >> +    kernel-module-tps6594-i2c \
> >> >> +"
> >> >
> >> > Are these all the modules we'll need? Is everything else build-in the 
> >> > default defconfig? or are we expecting this list to expand as more 
> >> > platforms start migrating to this?
> >> >
> >> > ~Bryan
> >> 
> >> Should this instead be defined per machine with
> >> MACHINE_ESSENTIAL_EXTRA_RDEPENDS?
> >> 
> >> https://docs.yoctoproject.org/ref-manual/variables.html#term-MACHINE_ESSENTIAL_EXTRA_RDEPENDS
> >
> > Yeah, I guess what I'm slowly realizing is we're adding roughly a 140MB 
> > binary to the critical path for the bootloaders (so long any boot KPI) 
> > all so we can have a PMIC driver as a builtin.
> >

Small correction. The evil vendor u-boot patches I saw we made room for 
140MB however building this locally just now it's closer to 70MB so half 
as bad but still more than 3 times the size of the kernel :(

> > All the distributions I can think of all modify the ARM64 defconfig in 
> > some way to better suit their distribution. Yocto even has the advantage 
> > of knowing what target they are building for. Should we instead carry a 
> > fragment, or use some other mechanism, to change the kernel's config so 
> > the PMIC driver is a builtin if needed by the target?
> >
> > ~Bryan
> 
> Use of conditional configs is simply reverting back to the schemes we were using
> 3+ years ago. Initramfs is big and slow, but it's standard and can be leveraged
> across other distros easily as it's already been a production solution for them
> for quite some time.
> 
> That being said, Yocto is *unique*, and what it doesn't do weird itself, it
> leaves for the implementer to make weird in their own way. I guess it doesn't
> really matter if we don't care about having a uniform bootflow across distros,
> but that sounds like hell.
> 

oh I agree, we can also fall back to a busybox shell if the MMC or flash 
is corrupted. There is tons of benefit if we don't care about boot time. 
I'm just not sure when we enable this, everyone will be happy about it

~Bryan

Re: [meta-arago] [meta-ti][PATCH 1/1 v2] recipes-ti: initramfs: Make minimal initrd image

[Moteen Shah]

Hey Bryan,

On 11/09/25 01:02, Bryan Brattlof wrote:
> On September 10, 2025 thus sayeth Randolph Sapp:
>> On Wed Sep 10, 2025 at 6:48 AM CDT, Bryan Brattlof wrote:
>>> On September  9, 2025 thus sayeth Randolph Sapp:
>>>> On Tue Sep 9, 2025 at 9:56 AM CDT, Bryan Brattlof via lists.yoctoproject.org wrote:
>>>>> On September  4, 2025 thus sayeth Moteen Shah:
>>>>>> Add recipes to make initramfs image based on systemd.
>>>>>> The image will package boot essential and other modules
>>>>>> which will be modprobed by initramfs udev once the inbuilt
>>>>>> drivers gets probed.
>>>>>>
>>>>>> Signed-off-by: Moteen Shah <m-shah@ti.com>
>>>>>> ---
>>>>>>   .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
>>>>>>   .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
>>>>>>   2 files changed, 54 insertions(+)
>>>>>>   create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>>>>>>   create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>>>>>>
>>>>>> diff --git a/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>>>>>> new file mode 100644
>>>>>> index 00000000..5d2ff390
>>>>>> --- /dev/null
>>>>>> +++ b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>>>>>> @@ -0,0 +1,5 @@
>>>>>> +SUMMARY = "Minimal initramfs for boot requirements"
>>>>>> +
>>>>>> +require recipes-core/packagegroups/packagegroup-core-boot.bb
>>>>>> +
>>>>>> +RDEPENDS:${PN}:remove = "grub-efi kernel"
>>>>>> diff --git a/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>>>>>> new file mode 100644
>>>>>> index 00000000..4cebf595
>>>>>> --- /dev/null
>>>>>> +++ b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>>>>>> @@ -0,0 +1,49 @@
>>>>>> +SUMMARY = "TI SDK super minimal base image for initramfs"
>>>>>> +
>>>>>> +DESCRIPTION = "Image meant for basic boot of linux kernel. Intended as\
>>>>>> + bare system, this image does not package the kernel in the\
>>>>>> + standard /boot folder in rootfs. Instead, it provides a base\
>>>>>> + rootfs allowing kernel to be deployed elsewhere\
>>>>>> + (tftp/separate boot partition/jtag log etc..) and boot\
>>>>>> + the image.\
>>>>>> +"
>>>>>> +
>>>>>> +LICENSE = "MIT"
>>>>>> +
>>>>>> +inherit core-image
>>>>>> +
>>>>>> +IMAGE_FEATURES:remove = "package-management"
>>>>>> +
>>>>>> +INITRAMFS_FSTYPES = "cpio cpio.xz"
>>>>>> +
>>>>>> +#INITRAMFS_MAXSIZE = "65536"
>>>>>> +#IMAGE_OVERHEAD_FACTOR = "1"
>>>>>> +
>>>>>> +IMAGE_FSTYPES = "${INITRAMFS_FSTYPES}"
>>>>>> +
>>>>>> +INITRAMFS_SCRIPTS ?= "initramfs-framework-base initramfs-module-udev initramfs-module-nfsrootfs"
>>>>>> +
>>>>>> +MODULES = "\
>>>>>> +    kernel-module-cdns-pltfrm \
>>>>>> +    kernel-module-ti-j721e-ufs \
>>>>>> +    kernel-module-tps6594-i2c \
>>>>>> +"
>>>>> Are these all the modules we'll need? Is everything else build-in the
>>>>> default defconfig? or are we expecting this list to expand as more
>>>>> platforms start migrating to this?
>>>>>
>>>>> ~Bryan
>>>> Should this instead be defined per machine with
>>>> MACHINE_ESSENTIAL_EXTRA_RDEPENDS?
>>>>
>>>> https://docs.yoctoproject.org/ref-manual/variables.html#term-MACHINE_ESSENTIAL_EXTRA_RDEPENDS
>>> Yeah, I guess what I'm slowly realizing is we're adding roughly a 140MB
>>> binary to the critical path for the bootloaders (so long any boot KPI)
>>> all so we can have a PMIC driver as a builtin.
>>>
> Small correction. The evil vendor u-boot patches I saw we made room for
> 140MB however building this locally just now it's closer to 70MB so half
> as bad but still more than 3 times the size of the kernel :(
>
>>> All the distributions I can think of all modify the ARM64 defconfig in
>>> some way to better suit their distribution. Yocto even has the advantage
>>> of knowing what target they are building for. Should we instead carry a
>>> fragment, or use some other mechanism, to change the kernel's config so
>>> the PMIC driver is a builtin if needed by the target?
>>>
>>> ~Bryan
>> Use of conditional configs is simply reverting back to the schemes we were using
>> 3+ years ago. Initramfs is big and slow, but it's standard and can be leveraged
>> across other distros easily as it's already been a production solution for them
>> for quite some time.
>>
>> That being said, Yocto is *unique*, and what it doesn't do weird itself, it
>> leaves for the implementer to make weird in their own way. I guess it doesn't
>> really matter if we don't care about having a uniform bootflow across distros,
>> but that sounds like hell.
>>
> oh I agree, we can also fall back to a busybox shell if the MMC or flash
> is corrupted. There is tons of benefit if we don't care about boot time.
> I'm just not sure when we enable this, everyone will be happy about it
>
> ~Bryan
>

Size was the concern for me as well while developing this. The issue 
here is
there is a lot of systemd stuff going in the background contributing to 
the size.
If you remove systemd and use busybox instead, you will observe that the 
image
size gets dropped to around 20 MB's. That solves our sizing issue but it 
brings on
its own set of challenges:

1. meta-ti and meta-arago currently has a global define for init manager 
which is
systemd, making them to support multi-config (multiple init manager) 
isn't that
straight forward.
2. Currently, this image is being used to modprobe extra modules and 
down the
line if we want to have a secure boot setup with dm-crypt, LUKS, etc to 
unlock
encrypted rootfs, systemd's own infra might come in handy.

Regards,
Moteen

Re: [meta-arago] [meta-ti][PATCH 1/1 v2] recipes-ti: initramfs: Make minimal initrd image

[Randolph Sapp]

On Fri Sep 12, 2025 at 4:42 AM CDT, Moteen Shah wrote:
> Hey Bryan,
>
> On 11/09/25 01:02, Bryan Brattlof wrote:
>> On September 10, 2025 thus sayeth Randolph Sapp:
>>> On Wed Sep 10, 2025 at 6:48 AM CDT, Bryan Brattlof wrote:
>>>> On September  9, 2025 thus sayeth Randolph Sapp:
>>>>> On Tue Sep 9, 2025 at 9:56 AM CDT, Bryan Brattlof via lists.yoctoproject.org wrote:
>>>>>> On September  4, 2025 thus sayeth Moteen Shah:
>>>>>>> Add recipes to make initramfs image based on systemd.
>>>>>>> The image will package boot essential and other modules
>>>>>>> which will be modprobed by initramfs udev once the inbuilt
>>>>>>> drivers gets probed.
>>>>>>>
>>>>>>> Signed-off-by: Moteen Shah <m-shah@ti.com>
>>>>>>> ---
>>>>>>>   .../initramfs/packagegroup-ti-initramfs.bb    |  5 ++
>>>>>>>   .../recipes-ti/initramfs/ti-tiny-initramfs.bb | 49 +++++++++++++++++++
>>>>>>>   2 files changed, 54 insertions(+)
>>>>>>>   create mode 100644 meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>>>>>>>   create mode 100644 meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>>>>>>>
>>>>>>> diff --git a/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>>>>>>> new file mode 100644
>>>>>>> index 00000000..5d2ff390
>>>>>>> --- /dev/null
>>>>>>> +++ b/meta-ti-bsp/recipes-ti/initramfs/packagegroup-ti-initramfs.bb
>>>>>>> @@ -0,0 +1,5 @@
>>>>>>> +SUMMARY = "Minimal initramfs for boot requirements"
>>>>>>> +
>>>>>>> +require recipes-core/packagegroups/packagegroup-core-boot.bb
>>>>>>> +
>>>>>>> +RDEPENDS:${PN}:remove = "grub-efi kernel"
>>>>>>> diff --git a/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>>>>>>> new file mode 100644
>>>>>>> index 00000000..4cebf595
>>>>>>> --- /dev/null
>>>>>>> +++ b/meta-ti-bsp/recipes-ti/initramfs/ti-tiny-initramfs.bb
>>>>>>> @@ -0,0 +1,49 @@
>>>>>>> +SUMMARY = "TI SDK super minimal base image for initramfs"
>>>>>>> +
>>>>>>> +DESCRIPTION = "Image meant for basic boot of linux kernel. Intended as\
>>>>>>> + bare system, this image does not package the kernel in the\
>>>>>>> + standard /boot folder in rootfs. Instead, it provides a base\
>>>>>>> + rootfs allowing kernel to be deployed elsewhere\
>>>>>>> + (tftp/separate boot partition/jtag log etc..) and boot\
>>>>>>> + the image.\
>>>>>>> +"
>>>>>>> +
>>>>>>> +LICENSE = "MIT"
>>>>>>> +
>>>>>>> +inherit core-image
>>>>>>> +
>>>>>>> +IMAGE_FEATURES:remove = "package-management"
>>>>>>> +
>>>>>>> +INITRAMFS_FSTYPES = "cpio cpio.xz"
>>>>>>> +
>>>>>>> +#INITRAMFS_MAXSIZE = "65536"
>>>>>>> +#IMAGE_OVERHEAD_FACTOR = "1"
>>>>>>> +
>>>>>>> +IMAGE_FSTYPES = "${INITRAMFS_FSTYPES}"
>>>>>>> +
>>>>>>> +INITRAMFS_SCRIPTS ?= "initramfs-framework-base initramfs-module-udev initramfs-module-nfsrootfs"
>>>>>>> +
>>>>>>> +MODULES = "\
>>>>>>> +    kernel-module-cdns-pltfrm \
>>>>>>> +    kernel-module-ti-j721e-ufs \
>>>>>>> +    kernel-module-tps6594-i2c \
>>>>>>> +"
>>>>>> Are these all the modules we'll need? Is everything else build-in the
>>>>>> default defconfig? or are we expecting this list to expand as more
>>>>>> platforms start migrating to this?
>>>>>>
>>>>>> ~Bryan
>>>>> Should this instead be defined per machine with
>>>>> MACHINE_ESSENTIAL_EXTRA_RDEPENDS?
>>>>>
>>>>> https://docs.yoctoproject.org/ref-manual/variables.html#term-MACHINE_ESSENTIAL_EXTRA_RDEPENDS
>>>> Yeah, I guess what I'm slowly realizing is we're adding roughly a 140MB
>>>> binary to the critical path for the bootloaders (so long any boot KPI)
>>>> all so we can have a PMIC driver as a builtin.
>>>>
>> Small correction. The evil vendor u-boot patches I saw we made room for
>> 140MB however building this locally just now it's closer to 70MB so half
>> as bad but still more than 3 times the size of the kernel :(
>>
>>>> All the distributions I can think of all modify the ARM64 defconfig in
>>>> some way to better suit their distribution. Yocto even has the advantage
>>>> of knowing what target they are building for. Should we instead carry a
>>>> fragment, or use some other mechanism, to change the kernel's config so
>>>> the PMIC driver is a builtin if needed by the target?
>>>>
>>>> ~Bryan
>>> Use of conditional configs is simply reverting back to the schemes we were using
>>> 3+ years ago. Initramfs is big and slow, but it's standard and can be leveraged
>>> across other distros easily as it's already been a production solution for them
>>> for quite some time.
>>>
>>> That being said, Yocto is *unique*, and what it doesn't do weird itself, it
>>> leaves for the implementer to make weird in their own way. I guess it doesn't
>>> really matter if we don't care about having a uniform bootflow across distros,
>>> but that sounds like hell.
>>>
>> oh I agree, we can also fall back to a busybox shell if the MMC or flash
>> is corrupted. There is tons of benefit if we don't care about boot time.
>> I'm just not sure when we enable this, everyone will be happy about it
>>
>> ~Bryan
>>
>
> Size was the concern for me as well while developing this. The issue 
> here is
> there is a lot of systemd stuff going in the background contributing to 
> the size.
> If you remove systemd and use busybox instead, you will observe that the 
> image
> size gets dropped to around 20 MB's. That solves our sizing issue but it 
> brings on
> its own set of challenges:
>
> 1. meta-ti and meta-arago currently has a global define for init manager 
> which is
> systemd, making them to support multi-config (multiple init manager) 
> isn't that
> straight forward.
> 2. Currently, this image is being used to modprobe extra modules and 
> down the
> line if we want to have a secure boot setup with dm-crypt, LUKS, etc to 
> unlock
> encrypted rootfs, systemd's own infra might come in handy.
>
> Regards,
> Moteen

Stop blaming systemd here. It may be large, but Arch Linux can build a
compressed initial ramdisk with systemd that's only 36MB in size. Something else
is bloating the image.

- Randolph

Re: [meta-ti][PATCH 0/1 v2] Add recipes to build initramfs image

[PRC Automation]

meta-arago / na / 20250904124331.1075343-1-m-shah

PRC Results: FAIL

=========================================================
  check-yocto-patches: FAIL
=========================================================
Patches
----------------------------------------
FAIL - [meta-ti][PATCH 0/1 v2] Add recipes to build initramfs image
    WARN: Missing branches specifier [master/scarthgap/XXXXX]. (META-2)
        patch:44
            Subject: [meta-ti][PATCH 0/1 v2] Add recipes to build initramfs image
    
    ERROR: Missing Signed-off-by in commit message. (SIGNED-OFF-BY-1)
        patch