Bootswapping operation is very unstable, even more in release

Question

Hi everyone, 
 
 Context of the project 
 I'm working on a bootloader project based on RL78. I set my memory like this : 
 
 This idea is to jump from application to bootloader when I want to update the application and to jump from bootloader to application when I'm finished with the upload. 
 
 Major Issue 
 I'm able to start bootloader, flash the program, jump to application, jump to bootloader and flash program again. But this is ok like 50% of the time in DEBUG. The first start and flash is always working, the first jump is almost always working and after that it depends. 
 In release mode, it is even worse. I can start bootloader, flash the program and most of the time I can't even jump to the application 
 
 How did I code that ? 
 I'm based on the renesas FSL library and working on the R5F10DPJ microcontroller. To perform the bootswapping, I'm using this function : 
 void Flash_SwapBootCluster()
{
	fsl_u08 fsl_status;
	UINT32 wait;
	
	// Open FSL and prepare all functions
	FSL_Open();
	FSL_PrepareExtFunctions();

	// Invert bootflag to start correct bootloader and close FSL
	fsl_status = FSL_InvertBootFlag();
	while(fsl_status != FSL_OK)
	{
 fsl_status = FSL_InvertBootFlag();
	}

	// Close FSL
	FSL_Close();

	/* Delay */
	wait = (UINT32)0;
	while(wait < (UINT32)10000)
	{
 wait++;
	}

	// Perform swapping of bootcluster
	fsl_status = FSL_SwapBootCluster();
	while(fsl_status != FSL_OK)
	{
 fsl_status = FSL_SwapBootCluster();
	}
} 
 I start to be out of idea, am I doing something wrong with this boot swapping ? 
 
 Thanks in advance and have a good day !

Lazy Dridri · Accepted Answer

What I meant is that IAR is based, by default, on the cstartup.s87 located in installation folder. So I copy paste it to my project and modified it to avoid modifying the default file for other project. 
 Here is my cstartup file, for IAR 
 cstartup.zip 
 I modified those lines since it look the same as you for your startup file (In comment, after 'Adrien -', is the initial line) 
 ; Init stack segment for as the generated code may sometimes
 ; access the 4th byte of a return address before it is initialized
 MOVW HL, #LWRD(0xBF00) ;Adrien - MOVW HL, #sfb(CSTACK) ;
 MOVW BC, #LWRD(0x3FE0) ;Adrien - MOVW BC, #LWRD(sizeof(CSTACK))
 CMP0 C
 SKZ
 INC B
 MOV A, #0xCD ; 0xCD to fool C-SPY's stack limit check
loop_s:
 MOV [HL], A
 INCW HL
 DEC C
 BNZ loop_s
 DEC B
 BNZ loop_s

 MOV CS, #0 
 I tried added your lines in my startup file but I got errors unfortunately. I'm quite a newbie in assembly :/ 
 Sorry for taking a lot of your time with this issue 
 
 EDIT : I also tried another thing, set the RPERDIS flag to 1, to avoid reset link to RAM parity error 
 EDIT 2 : After reset, RPERDIS is reset to 0 and a parity error might happen before I set it again so it may be useless in my case then 
 EDIT 3 : Alright, RAM Initialization was the answer like you said. It was important to fill with 0xAA while my code was filling with 0xCD. Thanks a lot !

AZ_Renesas · Answer

Hello, 
 First of all your memory layout is a bit confusing. 
 There should be boot cluster 0 (for the one boot program) and boot program 1 (for the other boot program), if you want to use the boot swap mechanism. On top of them there should be the application(s). 
 The boot program must exist only inside the memory size of a boot cluster. 
 Regarding the boot swap, after calling FSL_InvertBootFlag you should issue a software reset so the boot swap takes place. The new bootloader is active after reset.

Bootswapping operation is very unstable, even more in release

Top Replies