Does ls1043a PPA support PSCI function from 32-bit mode core?

[uncoldice]

Hi,

LS1043A supports two mode: 64-bit mode and 32-bit compatibility mode. 

I have verified PSCI functions on 64-bit mode, everything goes fine.

Below is two examples (using pseudo code)

• query the PSCI version

move x0, 0x84000000  

smc 0

Then I got result x0 = 0x00000002, means the PSCI version is 0.2

• boot up secondary core

move x0, 0xc4000003

move x1, cpuId

move x2, imageEntry

smc 0

Then I got result x0 = 0x0, and secondary core is up

But When I run the CPU on 32 bit compatibility mode (el1 is running on 32-bit), I found the two examples can not work at all. Code is like this:

• query the PSCI version

move r0, 0x84000000  

smc 0

Then I got result r0 = 0x84000000

• boot up secondary core

move r0, 0x84000003

move r1, cpuId

move r2, imageEntry

smc 0

Then I got result r0 = 0x84000003, and secondary core is not up at all

The test env is:

• LS1043ardb board
• U-boot and ppa.itb are all from "QorIQ Linux SDK v2.0 AARCH64 IMAGE.iso" downloaded from https://nxp.flexnetoperations.com/control/frse/download?element=7726177 

Here my question is:

1. does my above test approves that PPA support smc command from a 32-bit core?

2. if no, can you please share me the correct way to use PSCI?

3. if yes, is there a workaround to boot up a secondary core without using smc command?

Thanks.

[bpe]

>1. does my above test approves that PPA support smc command from a 32-bit core?

>2. if no, can you please share me the correct way to use PSCI?

>

[Platon] It is not possible to tell what is wrong with your code without stepping through it in a debugger. Make sure you are using the most recent PPA binary and see how 32-bit Linux invokes PSCI calls in the following kernel source files:

arch/arm/kernel/psci-call.S
arch/arm/kernel/psci.c
arch/arm/kernel/psci_smp.c

>3.Is there a workaround to boot up a secondary core without using smc command?

[Platon]  See how PPA does it in soc.c. Refer to LS1043ARM, Sections 12.3.15 and 11.3.54 for more
information. If you are doing it directly from your code, PPA should not be loaded/initialized.

Have a great day,
Platon

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