arm64: defconfig: Switch Ethernet drivers to modules

Development of Linux kernel progressed over last 10 years and it is easy
to generate now initramfs for building own kernel, e.g. with Yocto or
mkosi.  Therefore for a few years of reviews on mailing lists, all new
options enabled in arm64 defconfig were with assumption of having
initramfs which can load bare minimum of modules to mount filesystem
from network or disk.  Basically network driver as built-in is not
anymore essential to boot the system, so switch almost all Ethernet
drivers to modules to save on kernel image size.

Similarly 9P network filesystem for QEMU, especially that testing kernel
unuder QEMU does not have any size or build process constraints and can
use initramfs with -initrd argument.  Note that having network drivers
does not break NFS root, because whatever loading method, e.g. TFTP,
which brought the kernel image can bring also the initramfs with network
adapters (and I have been using such method for years for my Samsung
boards).

Notable exceptions / diff explanations:

1. Mark I2C as built-in, used by CONFIG_IGB as a module.

2. CONFIG_BCM4908_ENET and CONFIG_BCMASP appear in the diff, because
   they were default=y (via ARCH_BCMBCA or ARCH_BCM_IPROC).

3. CONFIG_HNS3_HCLGE and CONFIG_HNS3_ENET are removed, because they are
   default=m.

Moving code to modules has positive impact on kernel image size, thus
boot time of all users not using above drivers and ability to flash
fixed-size boot partitions.

Old Image size: 41.2 MiB (Image.gz: 14.8 MiB)
New Image size: 39.1 MiB (Image.gz: 13.8 MiB)

bloat-o-meter of vmlinux:
add/remove: 3/6972 grow/shrink: 6/45 up/down: 66659/-2333659 (-2267000)

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20260429-defconfig-v2-5-e4ed4186028b@oss.qualcomm.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

0 files changed, 0 insertions, 0 deletions