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DRA829V: Unable to hotplug CPU1 from Linux

Part Number: DRA829V

Hi TI experts,

We're trying to test CPU hotplug on the TI Jacinto7 EVM platform. The CPU goes offline correctly but then when we try bring it back online it fails. Here are the logs.

cpuinfo

root@j7-evm:~# cat /proc/cpuinfo
processor       : 0
BogoMIPS        : 400.00
Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
CPU implementer : 0x41
CPU architecture: 8
CPU variant     : 0x1
CPU part        : 0xd08
CPU revision    : 0

processor       : 1
BogoMIPS        : 400.00
Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
CPU implementer : 0x41
CPU architecture: 8
CPU variant     : 0x1
CPU part        : 0xd08
CPU revision    : 0

take the cpu1 offline

root@j7-evm:~# echo 0 > /sys/devices/system/cpu/cpu1/online
[  214.786894] CPU1: shutdown
[  214.789593] psci: CPU1 killed (polled 0 ms)
root@j7-evm:~# 
root@j7-evm:~# cat /proc/cpuinfo
processor       : 0
BogoMIPS        : 400.00
Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
CPU implementer : 0x41
CPU architecture: 8
CPU variant     : 0x1
CPU part        : 0xd08
CPU revision    : 0

now try to bring it back up again

root@j7-evm:~# echo 1 > /sys/devices/system/cpu/cpu1/online
[  229.726287] CPU1: failed to come online
[  229.730112] CPU1: failed in unknown state : 0x0
-sh: echo: write error: Input/output error
root@j7-evm:~# 
root@j7-evm:~# cat /proc/cpuinfo
processor       : 0
BogoMIPS        : 400.00
Features        : fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid
CPU implementer : 0x41
CPU architecture: 8
CPU variant     : 0x1
CPU part        : 0xd08
CPU revision    : 0

Please suggest what might be going wrong here.