AM6442 cann't change smp_affinity

fenghua jiang

Intellectual 631 points

Other Parts Discussed in Thread: AM6442, DRA821, TDA4VM

There are two cores on AN6642,and three networks on AM6442.

I want to modify /proc/irq/***/smp_affinity

175: 0 0 MSI-INTA 1971728 Level 8000000.ethernet

328: 0 0 GICv3 134 Level 8000000.ethernet

I can modify /proc/irq/328/smp_affinity, but cann't modify /proc/irq/175/smp_affinity

echo "1" > /proc/irq/175/smp_affinity
-sh: echo: write error: Invalid argument

I have stop the service of irqbalance

over 4 years ago

0 Schuyler Patton over 4 years ago

TI__Mastermind 41240 points

Hi,

I will have to confirm if there is an issue with setting irq affinity on the AM64x processors. Which TI SDK kernel are you using? Could you please post the results of uname -a?

Best Regards

Schuyler

0 fenghua jiang over 4 years ago in reply to Schuyler Patton

Intellectual 631 points

ti-processor-sdk-linux-rt-am64xx-evm-08.00.00.21

root@am64xx-evm:~# uname -a
Linux am64xx-evm 5.10.41-rt39-g0701a5b58c #10 SMP PREEMPT_RT Wed Nov 17 17:53:40 CST 2021 aarch64 aarch64 aarch64 GNU/Linux

0 Schuyler Patton over 4 years ago in reply to fenghua jiang

TI__Mastermind 41240 points

Hi,

I checked with a member of the development team and unfortunately the AM6442 irq router and aggregator drivers do not support SMP affinity.

Best Regards,

Schuyler

0 fenghua jiang over 4 years ago in reply to Schuyler Patton

Intellectual 631 points

what about TDA4VM/DRA821/SK_TDA4VM?

0 Nick Saulnier over 4 years ago in reply to fenghua jiang

TI__Guru** 108980 points

Hello Fenghua,

I am sending your thread over to the Jacinto team to comment on whether their processors support SMP affinity. Please note that responses may be delayed due to the Thanksgiving holidays. If you have not received a response by the week after thanksgiving, please ping the thread.

Regards,

Nick

0 fenghua jiang over 4 years ago

Intellectual 631 points

am57xx with RT kernel(ti-rt-linux-4.9.y)

assign network interrupts to only one cpu using cpu affinity settings

0 fenghua jiang over 4 years ago

Intellectual 631 points

am57xx-evm with RT kernel(ti-rt-linux-4.9.y) support it

network interrupts to pnly one CPU using cpu affinty settings

0 Karthik Ramanan over 4 years ago in reply to fenghua jiang

TI__Guru** 113810 points

Fenghua Jiang,

In general, this should be supported on TDA4VM/DRA821/SK_TDA4VM.

Note that only TDA4VM currently has the RT-Linux enablement.

If you have a test case that you want us to check on the TDA4VM/DRA821/SK_TDA4VM, please share and we can run the same and confirm.

Regards

Karthik

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AM6442 cann't change smp_affinity