Compiler/AM5728: SIMD for IPU

Vincenzo Scianni54

Part Number: AM5728

Tool/software: TI C/C++ Compiler

Hello.

Reading TRM for Sitara AM572x family, I found in paragraph 7.1.2 about dual Cortex-M4 IPU subsystem that each IPU integrates ARMv6 SIMD and digital signal processor (DSP) extensions but when I try to enable SIMD option in Properties->Build->ARM Compiler->Advanced Options->Runtime Model Options I get first an error message as shown in the following picture:

and later, if I launch a compilation, I will get :

error #24018-D: Option --neon is not valid without -mv7A8
gmake: *** [main.obj] Error 1
gmake: Target 'all' not remade because of errors.

So the question is : is it a compiler problem/bug or datasheet is reporting something wrong ?

Let me add that the problem is present in TI's compiler v17.9.0 STS and v16.9.4 LTS.

Thank you and best regards,

Scianni Vincenzo

over 7 years ago

0 Biser Gatchev-XID over 7 years ago

TI__Guru**** 393215 points

The software team have been notified. They will respond here.

0 Garrett Ding over 7 years ago in reply to Biser Gatchev-XID

TI__Mastermind 43296 points

Hi Scianni,

The "ARMv6 SIMD" specified in data sheet is different with the "SIMD instruction targeting NEON" option listed in IPU compiler, see the NEON-Advanced SIMD vs. SIMD discussion in ARM community. To enable SIMD instruction targeting NEON, the processor has to be with armv7/armv8 architecture.

Regards,
Garrett

0 Vincenzo Scianni54 over 7 years ago in reply to Garrett Ding

Intellectual 310 points

Hello Mr. Garret,

thank you for the clarification but how to use/generate SIMD instructions ? And where are intrinsic functions ?

And let me ask a clarification about CRC unit : reading some ARM forum Cortex M4, or at least some versions of it, integrates a CRC unit. Is this the case of IPU or do I need to implement it in sw ?

Thank you again and best regards.

Scianni Vincenzo

0 Garrett Ding over 7 years ago in reply to Vincenzo Scianni54

TI__Mastermind 43296 points

Hi Scianni,

GCC doesn't provides armv6 SIMD intrinsic instruction. You might want to implement such functions with inline assembly.

CRC unit is not listed in TRM www.ti.com/.../spruhz6. You need to implement it in sw.

Regards,
Garrett

0 Vincenzo Scianni54 over 7 years ago in reply to Garrett Ding

Intellectual 310 points

Hello Mr. Garret.

Thank you for the answer but I'm not using GCC: currently I'm using TI compiler v17.9.0.STS.

In any case I guess the situation could not be different between the two compilers so, if you have nothing to reply, I will follow your hint and I will consider closed this discussion.

Thank you again for your support.

Regards,

Scianni Vincenzo

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Compiler/AM5728: SIMD for IPU