Can't change the HDMI default output resolution thru BOARD_KERNEL_CMDLINE := video=HDMI-A-1:1920x1080@60

Products Support Poplar Board
#1

Dear Sir,

I would like to change the output HDMI default output resolution and I have read the article from
https://source.android.com/setup/build/devices#960kernel

So I add the line of below to ‘device/linaro/poplar/BoardConfig.mk’
BOARD_KERNEL_CMDLINE += video=HDMI-A-1:1920x1080@60

After BoardConfig.mk saved, I use the following command to rebuild boot.img
make -j4

And then burn the boot.img as following command in the fastboot mode
fastboot flash mmcsda2 boot.img

Everything look OK, and also can read the cmdline with ‘video=HDMI-A-1:1920x1080@60’ from /proc/cmdline, but the monitor resolution seem not changed.

video=HDMI-A-1:1920x1080@60 androidboot.hardware=poplar androidboot.selinux=permissive firmware_class.path=/vendor/firmware mmz=ddr,0,0,60M printk.devkmsg=on blkdevparts=mmcblk1:4193792@512(loader),40m(boot),1610612224(system),5993660928,268434944@1580m(vendor),268434944@1836m(cache),5364m@2092m(userdata) buildvariant=

Am I missing something?

#2

Poplar is a bit different here. Please try to add the following line into device.mk and see if it helps.

PRODUCT_PROPERTY_OVERRIDES += persist.sys.display.1080p=true

#3

It’s work 1080p perfect!! Thanks!

Is it current support 4k HDMI output or may have a plain in the future?