i.MX8 ULP Solo Emulation

[seah]

We want to evaluate whether the performance of i.MX8 ULP Solo/Single Core is acceptable to run latest NXP Android 14 release. Is there a u-boot or adb/debug console commands that we can run in real time to enable single core mode in i.MX8ULP Evaluation Kit (which has dual core)?

[raopdo]

This save my time. Thanks for your info.

[jimmychan]

There is kernel parameter "maxcpus" which is maximum number of processors that kernel should use.

For more information, you could refer to the Table 11 in the Release Notes below.

i.MX Linux Release Notes (nxp.com)

[seah]

Thanks. That's for Linux. Does Android 14 has similar setting?

[jimmychan]

It should be the same as u-boot also is the bootloader in Android 14.

[seah]

On Android 14, Here is the uboot printenv

=> printenv
arch=arm
baudrate=115200
board=imx8ulp_evk
board_name=imx8ulp_evk
bootcmd=boota mmc0
bootdelay=2
cpu=armv8
emmc_dev=0
ethaddr=00:04:9f:08:73:f6
ethprime=FEC
fastboot_dev=mmc0
fdt_high=0xffffffffffffffff
fdtcontroladdr=a3de8210
initrd_high=0xffffffffffffffff
loadaddr=0x80400000
sd_dev=2
sec_boot=yes
serial#=5fe72827b1363228
soc=imx8ulp
soc_type=imx8ulp
splashimage=0x90000000
splashpos=m,m
vendor=freescale

Environment size: 409/8188 bytes

I try to "setenv maxcpus 1", and the android still boot up with 2 CPUs

130|evk_8ulp:/ $ cat /proc/cpuinfo
processor : 0
BogoMIPS : 2.00
Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
CPU implementer : 0x41
CPU architecture: 8
CPU variant : 0x1
CPU part : 0xd04
CPU revision : 0

processor : 1
BogoMIPS : 2.00
Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
CPU implementer : 0x41
CPU architecture: 8
CPU variant : 0x1
CPU part : 0xd04
CPU revision : 0

The way that android set kernel parameters seems different from that of Linux. Please advise.

[jimmychan · Accepted solution]

please try "setenv append_bootargs maxcpus=1 "

[seah]

Thanks. It works!.

evk_8ulp:/ $ cat /proc/cpuinfo
processor : 0
BogoMIPS : 2.00
Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
CPU implementer : 0x41
CPU architecture: 8
CPU variant : 0x1
CPU part : 0xd04
CPU revision : 0

evk_8ulp:/