Hard Fault on call to soft float routine

chris_f — Mon, 23 Sep 2013 13:29:42 GMT

Hi all,

I'm having some trouble with using floating point operations on a K10. I'm compiling with gcc with -mcpu=cortex-m4 -mabi=aapcs -mthumb -msoft-float.

I get a Hard Fault exception on executing the blx instruction highlighted below:

74 subfactor = LOOP_CYCLES*1e6/cpu_clockRate;

000008c2: movw r3, #61448 ; 0xf008

000008c6: movt r3, #8191 ; 0x1fff

000008ca: ldrh r3, [r3, #0]

000008cc: mov r0, r3

000008ce: blx 0x1458 <__floatsidf> <-- Core Hard Faults here

000008d2: mov r2, r0

000008d4: mov r3, r1

000008d6: add r1, pc, #56 ; (adr r1, 0x910 <cpu_Delay+88>)

000008d8: ldrd r0, r1, [r1]

000008dc: blx 0x17c4 <__divdf3>

000008e0: mov r2, r0

000008e2: mov r3, r1

000008e4: mov r0, r2

000008e6: mov r1, r3

000008e8: blx 0x19d0 <__fixdfsi>

000008ec: mov r3, r0

000008ee: strh r3, [r7, #14]

Looking at the code for the __floatsidf, it doesn't look like thumb code? Is this right? Am I missing a compiler flag?

__floatsidf:

00001458: teq r0, #0

0000145c: moveq r1, #0

00001460: bxeq lr

00001464: push {r4, r5, lr}

00001468: mov r4, #1024 ; 0x400

0000146c: add r4, r4, #50 ; 0x32

00001470: ands r5, r0, #-2147483648 ; 0x80000000

00001474: rsbmi r0, r0, #0

00001478: mov r1, #0

0000147c: b 0x1274 <__aeabi_dadd+336>

Re: Hard Fault on call to soft float routine

chris_f — Mon, 23 Sep 2013 20:21:13 GMT

Looks like I was lacking -mcpu=cortex-m4 in my linker options.

Re: Hard Fault on call to soft float routine

soledad — Tue, 24 Sep 2013 21:50:16 GMT

I am glad your issue is solved.

Re: Hard Fault on call to soft float routine

embeddedarchite — Fri, 25 Oct 2013 23:30:39 GMT

Can you please explain where you added the -mcpu=cortex-m4 for the linker? I'm trying to add this option to the linker flags (Xlinker [option]) but it gives error.

Thanks,

topic Re: Hard Fault on call to soft float routine in Kinetis Microcontrollers

Hard Fault on call to soft float routine

Re: Hard Fault on call to soft float routine

Re: Hard Fault on call to soft float routine

Re: Hard Fault on call to soft float routine