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Webserver STR91x with GCC: I need help!

Posted by Fabrizio on October 3, 2006
Hi, this message is for everyone that are working to porting webserver demo on STR91x using GCC.
This porting is a part of my thesis, and i must finish it within the month of November. Please i need some help. At this time i don't understand if there are the startup file or the porting file that don't work! When i compile the freertos .elf file and i load it into the board, the board it seems died! It is possible that i'm the only that is working to this porting? If there is someone that can help me, i can post my files here.

RE: Webserver STR91x with GCC: I need help!

Posted by Nobody/Anonymous on October 3, 2006
Do you have a decent debugger? If so can you say where the crash occurs.

Where did you get the startup files from?

You need to ensure the startup files:
i/setup IRQ and supervisor stacks
ii/handle interrupt entry and exit as per the iar example for the str9
iii/call main in supervisor mode

are you doing all these things?

RE: Webserver STR91x with GCC: I need help!

Posted by Fabrizio on October 3, 2006
Actually i aven't a decent debugger because the Ride Raisonance toolkit that i use doesn't provide a rom debugger and the ram debugger is limited to 16k. What i must used?
The startup file are provided by Raisonance and modified by me as follows:

.extern main
.extern exit
.extern VIC0_BASE
.extern VIC1_BASE

.code 32
.align 0

.extern _sidata
.extern _sdata
.extern _edata
.extern _sbss
.extern _ebss

;/* Standard definitions of Mode bits and Interrupt (I & F) flags in PSRs */
.set Mode_USR, 0x10 ;/* User Mode */
.set Mode_FIQ, 0x11 ;/* FIQ Mode */
.set Mode_IRQ, 0x12 ;/* IRQ Mode */
.set Mode_SVC, 0x13 ;/* Supervisor Mode */
.set Mode_ABT, 0x17 ;/* Abort Mode */
.set Mode_UND, 0x1B ;/* Undefined Mode */
.set Mode_SYS, 0x1F ;/* System Mode */

.equ I_Bit, 0x80 ;/* when I bit is set, IRQ is disabled */
.equ F_Bit, 0x40 ;/* when F bit is set, FIQ is disabled */

/*; --- System memory locations */

;/* init value for the stack pointer. defined in linker script */
.extern _estack

;/* Stack Sizes. The default values are in the linker script, but they can be overriden. */
SRAM_Base = 0x04000000
SRAM_Limit= 0x04018000

.setUND_Stack_Size, 0x00000004
.setABT_Stack_Size, 0x00000004
.setFIQ_Stack_Size, 0x00000004
.setIRQ_Stack_Size, 0x00000400
.setSVC_Stack_Size, 0x00000400


.section .flashtext
.code 32
.align 0
.globl _start
.globl _startup


ldr PC, Reset_Addr
ldr PC, Undefined_Addr
ldr PC, SWI_Addr
ldr PC, Prefetch_Addr
ldr PC, Abort_Addr
nop /*; Reserved vector*/
ldr pc, [pc,#-0xFF0] /*; IRQ Handler ***I use this but i think that isn't correct ***
ldr PC, Fiq_Addr

Reset_Addr : .long Reset_Handler
Undefined_Addr : .long UndefinedHandler
SWI_Addr: .longvPortYieldProcessor
Prefetch_Addr : .long PrefetchAbortHandler
Abort_Addr : .long DataAbortHandler
Fiq_Addr: .longFIQHandler
.long 0 /*; Reserved vector*/

UndefinedHandler : b . /* undefined*/
PrefetchAbortHandler: b . /* program abort*/
DataAbortHandler: b . /* data abort*/
FIQHandler: b . /* FIQ*/


/* Setup a stack for each mode - note that this only sets up a usable stack
for system/user, SWI and IRQ modes. Also each mode is setup with
interrupts initially disabled. */
ldr r0, =_estack
msrCPSR_c, #Mode_FIQ|I_Bit|F_Bit

msrCPSR_c, #Mode_IRQ|I_Bit|F_Bit

msrCPSR_c, #Mode_ABT|I_Bit|F_Bit

msrCPSR_c, #Mode_UND|I_Bit|F_Bit

msrCPSR_c, #Mode_SVC|I_Bit|F_Bit

msrCPSR_c, #Mode_SYS|I_Bit|F_Bit

/* We want to start in supervisor mode. Operation will switch to system
mode when the first task starts. */
msr CPSR_c, #Mode_SVC|I_Bit|F_Bit

;/* copy the initial values for .data section from FLASH to RAM */
ldrR1, =_sidata
ldrR2, =_sdata
ldrR3, =_edata

cmpR2, R3
ldrlOR0, [R1], #4
strlOR0, [R2], #4

;/* Clear the .bss section */
mov r0,#0;/* get a zero */
ldr r1,=_sbss;/* point to bss start */
ldr r2,=_ebss;/* point to bss end */

cmp r1,r2;/* check if some data remains to clear */
strlo r0,[r1],#4;/* clear 4 bytes */
blo _reset_inibss_loop;/* loop until done */

/*; --- Now enter the C code */
/* ldr PC, ___main
___main : .long main*/


The only problem is to handle the interrupt entry and exit. IAR use the IRQ_Handler function in 91x_vect.c and the portSAVE_Context and portRESTORE_Context are in the ISR_Support.h file.
In gcc port this file doesn't exist and the fuctions are included in portmacro.h as #define. if i use the IRQ_Handler on my startup file i obtain undefined reference error to portSAVE and portRESTORE from the compiler. For the rest, the file seems to be correct. Please take a look to the file. It's most important to me to know that is correct. Thanks!

RE: Webserver STR91x with GCC: I need help!

Posted by Nobody/Anonymous on October 3, 2006
>ldr pc, [pc,#-0xFF0] /*; IRQ Handler ***I use this but i think that isn't correct ***

This is not how the IAR example does it as you say and it might be that the -0xff0 is incorrect for the str9. The IAR demo uses:


then defines IRQ_Addr to save the context, call the switch function, then restore the context. You can copy the actual IRQ_Addr function from 91x_vect_IAR.s in the FreeRTOS download. The missing portSAVE_CONTEXT and portRESTORE_CONTEXT functions are defined in ISR_Support.h which is included at the top of 91x_vect_IAR.s. They are assembly macros that use the IAR syntax, I think you can simply change to use GAS (GNU assembler) syntax which is a bit simpler anyway.

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