My program consists of a bootloader and an app.
In the app, when I try to copy the .sdata section from flash to RAM, I get an IVOR1 exception.
If I copy the init_RAM function to my bootloader source code (and replace the linker symbols _etext, _edata, _data, _bss, _ebss) and call it from the bootloader, I don't get an IVOR1 exception.
The bootloader calls an entry-point function in the app, there are no restarts in between.
static void init_RAM(void) {
uint32_t *pulSrc, *pulDest;// Copy data segment initializers from flash to SRAM
pulSrc = &_etext;
for(pulDest = &_data; pulDest < &_edata; ) {
*pulDest++ = *pulSrc++;
}// Initialize bss section to zero
for(pulDest = &_bss; pulDest < &_ebss; )
*pulDest++ = 0;
}
My Bootentry.S file has code for initializing the SRAM ECC.
#***************************** Initialise SRAM ECC ***************************/
# Store number of 128Byte (32GPRs) segments in Counter
e_lis r5, __SRAM_SIZE@h # Initialize r5 to size of SRAM (Bytes)
e_or2i r5, __SRAM_SIZE@l
e_srwi r5, r5, 0x7 # Divide SRAM size by 128
mtctr r5 # Move to counter for use with "bdnz"# Base Address of the internal SRAM
e_lis r5, __SRAM_BASE_ADDR@h
e_or2i r5, __SRAM_BASE_ADDR@l# Fill SRAM with writes of 32GPRs
sram_loop:
e_stmw r0,0(r5) # Write all 32 registers to SRAM
e_addi r5,r5,128 # Increment the RAM pointer to next 128bytes
e_bdnz sram_loop # Loop for all of SRAM
The content of the MCSR register:
The C55FMC.MCR register:
Does this mean that the IVOR1 exception was not caused by reading from the flash? (When I've had IVOR1 problems with flash reads, then bits in the C55FMC.MCR register has been set).
The content of the 24 bytes .sdata section in flash.
The content in ram for [_data, _edata):
Any suggestions on how to proceed? How can I figure out if this is a problem in RAM or FLASH? I'm working on reducing this down to a program that I can post here for more feedback.
