This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

  • Resolved

Linux/AM5726: Deactivation of one ARM core

Intellectual 730 points

Replies: 2

Views: 123

Part Number: AM5726

Tool/software: Linux

Hi,

We are bringing up a custom board based on AM572x GP EVM. We are using SDK version 4.3.0.5. We are using a smaller PMIC TPS65916 rather than TPS659038, so we must disable one Cortex A15 at boot up. I'm reading this thread:

https://e2e.ti.com/support/arm/sitara_arm/f/791/t/551530  When I tried the fix suggested:

--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -481,7 +481,7 @@ int smp_call_function(smp_call_func_t func, void *info, int wait)
 EXPORT_SYMBOL(smp_call_function);
 
 /* Setup configured maximum number of CPUs to activate */
-unsigned int setup_max_cpus = NR_CPUS;
+unsigned int setup_max_cpus = 1;
 EXPORT_SYMBOL(setup_max_cpus);

I'm still seeing 2 CPS brought up and later kernel crashed (maybe due to the PMIC unable to sustain).

Could you please confirm if this change should still work on SDK 4.3.0.5? If not, what is the suggested way of doing this?

If there is a better way to do it through defconfig, could you clarify which config flags should be turned off? I have tried that but was unable to figured from the numerous flags that related to SMP.

Thank you!

Jan

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.