SVC and fault handling not passed to application

[tkorsdal]

First step of trying to integrate S132 to a small OS is failing completely.

When I use SVC the system ends up in hanging in hard fault.

The SoD handler ends up trying to read branch address from location 0xa891be2c - which causes the hardfault. (The hardfault handler itself has the same problem)

The SoD it not enabled - for now I have just moved the OS to 0x1f000/0x20002128.

Am I supposed to do any initialization for this?

The invalid memory location comes from the SVC handler reading @0x20000000 - why? I would have expected that passing handler is done to fixed vector table address at 0x1f000?

[tkorsdal]

Added the following in beginning of main: *( ( uint32_t *)0x20000000 ) = 0x00001000; *( ( uint32_t *)0x20000004 ) = 0x0001f000;

And then it works. What is the proper way to this?

[Susheel Nuguru]

you have to first figure out why your SVC handler is trying to read wrong memory. I am assuming SoD means softdevice, and the SVC handler that hangs is inside the OS you are trying to port.

Check if wrong stack pointer is selected for some reason. Which softdevice version are you using?

[tkorsdal]

It is the SVC handler of the softdevice that reads the wrong memory. In the blinky project, locations 0x20000000 and 0x20000004 is initialized when the software enters the application main. In my project it is not. If I initializes these two addresses at the beginning of application the handler works fine with SVC below 0x10 being forwarded to me. I suspect the problem is in my project settings and not code.

[Susheel Nuguru]

what project settings for IRAM and IROM are you using? and what is the softdevice version, please check your linker scripts if any for the application.

[tkorsdal]

The softdevice is version 3.0.0 (from SDK 12.1.0).

Here is my linker script - it has extra defines for being able to lock memory for a scheduled process:

    /*###ICF### Section handled by ICF editor, don't touch! ****/
/*-Editor annotation file-*/
/* IcfEditorFile="$TOOLKIT_DIR$\config\ide\IcfEditor\cortex_v1_1.xml" */
/*-Specials-*/
define symbol __ICFEDIT_intvec_start__ = 0x0001f000;
/*-Memory Regions-*/
define symbol __ICFEDIT_region_IROM1_start__ = 0x0001f000;
define symbol __ICFEDIT_region_IROM1_end__   = 0x0007FFFF;
define symbol __ICFEDIT_region_IROM2_start__ = 0x0;
define symbol __ICFEDIT_region_IROM2_end__   = 0x0;
define symbol __ICFEDIT_region_EROM1_start__ = 0x0;
define symbol __ICFEDIT_region_EROM1_end__   = 0x0;
define symbol __ICFEDIT_region_EROM2_start__ = 0x0;
define symbol __ICFEDIT_region_EROM2_end__   = 0x0;
define symbol __ICFEDIT_region_EROM3_start__ = 0x0;
define symbol __ICFEDIT_region_EROM3_end__   = 0x0;
define symbol __ICFEDIT_region_IRAM1_start__ = 0x20002128;
define symbol __ICFEDIT_region_IRAM1_end__   = 0x2000FFFF;
define symbol __ICFEDIT_region_IRAM2_start__ = 0x0;
define symbol __ICFEDIT_region_IRAM2_end__   = 0x0;
define symbol __ICFEDIT_region_ERAM1_start__ = 0x0;
define symbol __ICFEDIT_region_ERAM1_end__   = 0x0;
define symbol __ICFEDIT_region_ERAM2_start__ = 0x0;
define symbol __ICFEDIT_region_ERAM2_end__   = 0x0;
define symbol __ICFEDIT_region_ERAM3_start__ = 0x0;
define symbol __ICFEDIT_region_ERAM3_end__   = 0x0;
/*-Sizes-*/
define symbol __ICFEDIT_size_cstack__ = 0x800;
define symbol __ICFEDIT_size_heap__   = 0x200;
/**** End of ICF editor section. ###ICF###*/

define memory mem with size = 4G;
define region IROM_region   =   mem:[from __ICFEDIT_region_IROM1_start__ to __ICFEDIT_region_IROM1_end__]
                              | mem:[from __ICFEDIT_region_IROM2_start__ to __ICFEDIT_region_IROM2_end__];
define region EROM_region   =   mem:[from __ICFEDIT_region_EROM1_start__ to __ICFEDIT_region_EROM1_end__]
                              | mem:[from __ICFEDIT_region_EROM2_start__ to __ICFEDIT_region_EROM2_end__]
                              | mem:[from __ICFEDIT_region_EROM3_start__ to __ICFEDIT_region_EROM3_end__];
define region IRAM_region   =   mem:[from __ICFEDIT_region_IRAM1_start__ to __ICFEDIT_region_IRAM1_end__]
                              | mem:[from __ICFEDIT_region_IRAM2_start__ to __ICFEDIT_region_IRAM2_end__];
define region ERAM_region   =   mem:[from __ICFEDIT_region_ERAM1_start__ to __ICFEDIT_region_ERAM1_end__]
                              | mem:[from __ICFEDIT_region_ERAM2_start__ to __ICFEDIT_region_ERAM2_end__]
                              | mem:[from __ICFEDIT_region_ERAM3_start__ to __ICFEDIT_region_ERAM3_end__];


define block CSTACK    with alignment = 8, size = __ICFEDIT_size_cstack__   { };
define block HEAP      with alignment = 8, size = __ICFEDIT_size_heap__     { };

initialize by copy { readwrite };
do not initialize  { section .noinit };

// Code item definitions for memory protection
// ITEM: bsp_os
define block bsp_os_code with alignment = 0x2000, size = 0x2000 { 	section .bsp_os_code,
																section .bsp_os_rodata,
																section .bsp_utils_code,
																section .bsp_utils_rodata,
																object strlen.o,
																object ABImemset.o, 
																object ABImemcpy_unaligned.o,
																object strcpy_unaligned.o
															};															
															
define block bsp_os_data_upro with alignment = 0x200, size = 0x0200 { section .bsp_os_data, section .bsp_os_bss };
define block bsp_os_data_uprw with alignment = 0x400, size = 0x0400 { section .bsp_utils_data, section .bsp_utils_bss, section .bsp_uprw_data };

// ITEM: services_test
define block services_test_code with alignment = 0x0200, size = 0x0200 { section .services_test_code, section .services_test_rodata  };
define block services_test_data with alignment = 0x0100, size = 0x0100 { section .services_test_data, section .services_test_bss };
define block services_test2_code with alignment = 0x0100, size = 0x0100 { section .services_test2_code, section .services_test2_rodata  };
define block services_test2_data with alignment = 0x0100, size = 0x0100 { section .services_test2_data, section .services_test2_bss };

// ITEM: services_communication
define block services_communication_code with alignment = 0x0200, size = 0x0200 { section .services_communication_code, section .services_communication_rodata  };
define block services_communication_data with alignment = 0x0100, size = 0x0100 { section .services_communication_data, section .services_communication_bss };

place at address mem:__ICFEDIT_intvec_start__ { readonly section .intvec };

place in IROM_region  { readonly,
						block bsp_os_code,
						block services_test_code, 
						block services_test2_code,
						block services_communication_code
						};
						
place in EROM_region  { readonly section application_specific_ro };
place in IRAM_region  { readwrite,
						block CSTACK,
						block HEAP,
						block bsp_os_data_upro,
						block bsp_os_data_uprw,
						block services_test_data,
						block services_test2_data,
						block services_communication_data
						};
						
place in ERAM_region  { readwrite section application_specific_rw };