I have now set up new target freertos-arm and want to start playing arround with freertos.

I have compiled freertos with STM32CubeIDE, only 'problem' is that I need to compile with floting point enabled, with Soft-Float the build fails.

For STM32F401RE Chip the C-compiler selects

-mfpu=fpv4-sp-d16 -mfloat-abi=hard

but Freepascal doex not seem to support exactly this abi, I see: NONE
SOFT
LIBGCC
FPA
FPA10
FPA11
VFPV2
VFPV3
NEON_VFPV3
VFPV3_D16
FPV4_S16
VFPV4
NEON_VFPV4

Which setting should I use? VFPV3_D16 or something else?

Thank you,

Michael

Let's just add it. What properties does it have? Do you have know some reference by heard?

I found this reference manual for floating point instructions:

https://www.st.com/resource/en/programming_manual/dm00046982-stm32-cortexm4-mcus-and-mpus-programming-manual-stmicroelectronics.pdf

and this high level overview:

https://embeddedartistry.com/blog/2017/10/11/demystifying-arm-floating-point-compiler-options/

What is funny is that I did not find FPV4_S16 in the link above, only *VFPv4-D32,**VFPv4-D16 and ***VFPv4U**

Here:
https://sourceware.org/binutils/docs/as/ARM-Options.html#ARM-Options I only find |vfpv4|, |vfpv4-d16|, |fpv4-sp-d16| so no idea what FPV4_S16 actually is..

Michael

It is probably what Cortex-M4 needs. However, it does not seem to be completely correct. I'll add fpv4-sp-d16 (it means: single precision only with 32 registers, but for load/store/move they can be considered as 16 double registers) and fix everything

Am 12.04.20 um 10:49 schrieb

I'm pretty sure that's what fpv4_s16 is. That was implemented for cortex m4. Don't have the spec here currently though

Yes. It looks like this. Nevertheless, for consistent naming I'll add fpv4-sp-d16 with the same fpu capabilities as fpv4_s16 (which appears to be broken currently).

Thank you very much for your effort!

Michael

Michael Ring wrote

Thank you very much for your effort!

I added FPV4_SP_D16.

Thanks, but unfortunately this created some issues, both when I build plain armv6m/armv7em embedded compiler+rtl and my freertos target (Errors are the same)

armv6m embedded from trunk compiling without -Cf flag:

/Users/ring/fpcupdeluxe/fpc/bin/x86_64-darwin/ppcarm -Cparmv6m -Ur -Tembedded -Parm -XParm-embedded- -Xr -Ur -Xs -O2 -n -Fi../inc -Fi../arm -FD/Users/ring/fpcupdeluxe/fpc/bin/x86_64-darwin -FE. -FU/Users/ring/devel/fpc/rtl/units/arm-embedded -vw-n-h-l-d-u-t-p-c- -ap -darm -dRELEASE ../inc/iso7185.pp
iso7185.pp(267,13) Fatal: Internal error 2009112404

armv7em compiling with -CfFPV4_SP_D16

/Library/Developer/CommandLineTools/usr/bin/make -C embedded all /Users/ring/fpcupdeluxe/fpc/bin/x86_64-darwin/ppcarm -Cparmv7em -Ur -Tembedded -Parm -XParm-embedded- -Xr -Ur -Xs -O2 -n -Fi../inc -Fi../arm -FD/Users/ring/fpcupdeluxe/fpc/bin/x86_64-darwin -FE. -FU/Users/ring/devel/fpc/rtl/units/arm-embedded -vw-n-h-l-d-u-t-p-c- -ap -CfFPV4_SP_D16 -darm -dRELEASE  -Us -Sg system.pp @system.cfg {standard input}: Assembler messages:
{standard input}:19643: Error: selected FPU does not support instruction -- `vmov d0,r0,r1'

{standard input}:19659: Error: selected FPU does not support instruction -- `vmov d0,r0,r1'

Compiling the compiler+rtl worked fine before applying the following changes:

Updating 6d7560f142..94d20ceb05
Fast-forward
 compiler/arm/aasmcpu.pas  |  1 +
 compiler/arm/cgcpu.pas    | 43 +++++++++++++++++++++++++++----------------  compiler/arm/cpuinfo.pas  | 40 ++++++++++++++++++++++------------------  compiler/arm/narmadd.pas  |  6 +++---
 compiler/arm/narmcnv.pas  |  6 +++---
 compiler/arm/narminl.pas  | 12 ++++++------
 compiler/arm/narmmat.pas  |  4 ++--
 compiler/arm/narmutil.pas |  1 +
 compiler/globals.pas      |  1 +
 9 files changed, 66 insertions(+), 48 deletions(-)

In case you need the freertos target, it is here, work in progress, I am now creating freertos bindings:

http://temp.michael-ring.org/targetarmfreertos.patch

Hopefully all fixed.

Compile compiler&rtl works again!

Michael