cpu command
Synopsis
cpu list
cpu detail
cpu release <core ID> <addr>
Description
The cpu command prints information about the CPUs, and release a CPU core to a given address to run applications.
cpu list
The ‘list’ subcommand lists and prints brief information of all the CPU cores, the CPU information is provided by vendors’ CPU driver.
cpu detail
The ‘detail’ subcommand prints more details about the CPU cores, including CPU ID, core frequency and feature list.
cpu release
The ‘release’ subcommand is used to release a CPU core to run a baremetal or RTOS applications. The parameter <core ID> is the sequence number of the CPU core to release. The parameter <addr> is the address to run of the specified core after release.
Examples
cpu list
This example lists all the CPU cores On i.MX8M Plus EVK:
u-boot=> cpu list
0: cpu@0 NXP i.MX8MP Rev1.1 A53 at 1200 MHz at 31C
1: cpu@1 NXP i.MX8MP Rev1.1 A53 at 1200 MHz at 30C
2: cpu@2 NXP i.MX8MP Rev1.1 A53 at 1200 MHz at 31C
3: cpu@3 NXP i.MX8MP Rev1.1 A53 at 1200 MHz at 31C
cpu detail
This example prints the details of the CPU cores On i.MX8M Plus EVK:
u-boot=> cpu detail
0: cpu@0 NXP i.MX8MP Rev1.1 A53 at 1200 MHz at 31C
ID = 0, freq = 1.2 GHz: L1 cache, MMU
1: cpu@1 NXP i.MX8MP Rev1.1 A53 at 1200 MHz at 30C
ID = 0, freq = 1.2 GHz: L1 cache, MMU
2: cpu@2 NXP i.MX8MP Rev1.1 A53 at 1200 MHz at 31C
ID = 0, freq = 1.2 GHz: L1 cache, MMU
3: cpu@3 NXP i.MX8MP Rev1.1 A53 at 1200 MHz at 31C
ID = 0, freq = 1.2 GHz: L1 cache, MMU
cpu release
This example shows release the LAST CPU core to run a RTOS application, on i.MX8M Plus EVK:
u-boot=> load mmc 1:2 c0000000 /hello_world.bin
66008 bytes read in 5 ms (12.6 MiB/s)
u-boot=> dcache flush; icache flush
u-boot=> cpu release 3 c0000000
Released CPU core (mpidr: 0x3) to address 0xc0000000
Configuration
The cpu command is available if CONFIG_CMD_CPU=y.
Return code
The return value $? is set to 0 (true) if the command is successful, 1 (false) otherwise.