This looks like a hard one.
Intermittently, like once a day, I’m getting this:
CM4 FAULT!!
SCB->CFSR = 0x00008200
Bus Fault!
Fault address = 0x01000000
r0 = 0x00000000
r1 = 0xffffffff
r2 = 0x08045a48
r3 = 0xfff783ef
r12 = 0x100a875f
lr = 0x100a9450
pc = 0x81010000
psr = 0x3e01ec70
The call stack is:
1 Cy_SysLib_FaultHandler(const uint32_t * faultStackAddr = <optimized out>) Generated_Source\PSoC6\pdl\drivers/peripheral/syslib/cy_syslib.c 444 0x1008517A (All)
2 UsageFault_Handler() gcc/startup_psoc6_01_cm4.S 455 0x1008034E (All)
3 <signal handler called>() ?????? ?????? 0xFFFFFFED (All)
4 prvPortStartFirstTask() Generated_Source\PSoC6\pdl\rtos\FreeRTOS\10.0.1\Source\portable\GCC\CM4F/port.c 261 0x1008045C (All)
5 xPortStartScheduler() Generated_Source\PSoC6\pdl\rtos\FreeRTOS\10.0.1\Source\portable\GCC\CM4F/port.c 367 0x1008334C (All)
6 cy_ble_flashStorage() ?????? ?????? 0x14000E00 (All)
prvPortStartFirstTask() is:
/*-----------------------------------------------------------*/
static void prvPortStartFirstTask( void )
{
/* Start the first task. This also clears the bit that indicates the FPU is
in use in case the FPU was used before the scheduler was started - which
would otherwise result in the unnecessary leaving of space in the SVC stack
for lazy saving of FPU registers. */
__asm volatile(
" ldr r0, =0xE000ED08 \n" /* Use the NVIC offset register to locate the stack. */
" ldr r0, [r0] \n"
" ldr r0, [r0] \n"
" msr msp, r0 \n" /* Set the msp back to the start of the stack. */
" mov r0, #0 \n" /* Clear the bit that indicates the FPU is in use, see comment above. */
" msr control, r0 \n"
" cpsie i \n" /* Globally enable interrupts. */
" cpsie f \n"
" dsb \n"
" isb \n"
" svc 0 \n" /* System call to start first task. */
" nop \n"
);
}
/*-----------------------------------------------------------*/
I can’t find Fault address = 0x01000000 anywhere in the Disassembly of my program. However, if I follow link register lr = 0x100a9450 it points here:
0x100A944C b.n 100a9432 <__ieee754_sqrt+0x9a>
0x100A944E bic.w r6, r1, #80000000 ; 0x80000000
0x100A9452 orrs r6, r0
0x100A9454 beq.n 100a94c0 <__ieee754_sqrt+0x128>
0x100A9456 cmp r1, #0
I don’t claim to understand what I am looking at here, but I don’t think it’s a coincidence that my app is spending a lot of time in sqrt() and the link register is pointing to <__ieee754_sqrt+0x9a> and the comments in prvPortStartFirstTask( void ) are talking about manipulating Floating Point Unit (FPU) related things.
I’m building with this:
C:\Users\carlk>"C:\Program Files (x86)\Cypress\PSoC Creator\4.3\PSoC Creator\import\gnu\arm\9.3.1\bin\arm-none-eabi-gcc.exe " -v
Using built-in specs.
COLLECT_GCC=C:\Program Files (x86)\Cypress\PSoC Creator\4.3\PSoC Creator\import\gnu\arm\9.3.1\bin\arm-none-eabi-gcc.exe
COLLECT_LTO_WRAPPER=c:/program\ files\ (x86)/cypress/psoc\ creator/4.3/psoc\ creator/import/gnu/arm/9.3.1/bin/../lib/gcc/arm-none-eabi/9.3.1/lto-wrapper.exe
Target: arm-none-eabi
Configured with: /mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/src/gcc/configure --build=x86_64-linux-gnu --host=i686-w64-mingw32 --target=arm-none-eabi --prefix=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/install-mingw --libexecdir=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/install-mingw/lib --infodir=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/install-mingw/share/doc/gcc-arm-none-eabi/info --mandir=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/install-mingw/share/doc/gcc-arm-none-eabi/man --htmldir=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/install-mingw/share/doc/gcc-arm-none-eabi/html --pdfdir=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/install-mingw/share/doc/gcc-arm-none-eabi/pdf --enable-languages=c,c++ --enable-mingw-wildcard --disable-decimal-float --disable-libffi --disable-libgomp --disable-libmudflap --disable-libquadmath --disable-libssp --disable-libstdcxx-pch --disable-nls --disable-shared --disable-threads --disable-tls --with-gnu-as --with-gnu-ld --with-headers=yes --with-newlib --with-python-dir=share/gcc-arm-none-eabi --with-sysroot=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/install-mingw/arm-none-eabi --with-libiconv-prefix=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/build-mingw/host-libs/usr --with-gmp=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/build-mingw/host-libs/usr --with-mpfr=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/build-mingw/host-libs/usr --with-mpc=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/build-mingw/host-libs/usr --with-isl=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/build-mingw/host-libs/usr --with-libelf=/mnt/workspace/workspace/GCC-9-pipeline/jenkins-GCC-9-pipeline-200_20200521_1590053374/build-mingw/host-libs/usr --with-host-libstdcxx='-static-libgcc -Wl,-Bstatic,-lstdc++,-Bdynamic -lm' --with-pkgversion='GNU Arm Embedded Toolchain 9-2020-q2-update' --with-multilib-list=rmprofile,aprofile
Thread model: single
gcc version 9.3.1 20200408 (release) (GNU Arm Embedded Toolchain 9-2020-q2-update)
What is my next step in debugging this?
FreeRTOSConfig.h (9.3 KB)
