LCF_TRAPVEC0_START and LCF_STARTPTR_CPU0 values in Lcf_Gnuc_Tricore_Tc.lsl

[E-John]

Dear all,

refer linker file "Lcf_Gnuc_Tricore_Tc.lsl" under dirctory, (part of it see below) Aurix2G_Workspace_V1_0_1_13_0\BaseFramework_TC39B\1_ToolEnv\0_Build\1_Config\Config_Tricore_Gnuc

1. INTVEC0_START is from 0x802F E000 = (0x802F FFFF - 256 x 32 + 1) =  (0x802F FFFF - 0x2000 + 1), 256 interrupt and 32bytes for each one, total size is 0x2000 bytes, and it is from 0x802E 0000 to 0x802FFF, it is OK. The INTVEC1_START to INTVEC5_START can be got by the similar  way.

2. There are 8 traps of each CPUx, x from 0 to 5, the TRAPVEC size is 8 x 32 = 0x100

3. LCF_TRAPVEC1_START to LCF_TRAPVEC5_START are set to 0x8030 0000 to 0x80F0 0000, adjacent CPU is with a difference value 0x30 0000,

    LCF_STARTPTR_CPU1 to LCF_STARTPTR_CPU5 are set to 0x8030 0100 to 0x80F0 0100, adjacent CPU is with a difference value 0x30 0000.

4. For CPU0, LCF_TRAPVEC0_START is set to 0x80000100, the TRAP vector address is from 0x8000 0100 to 0x8000 0200? Why? Is there any special purpose to set this value?

and LCF_STARTPTR_CPU0 is set to 0x80000000, what are the address from 0x8000 0000 to 0x8000 00ff for?

LCF_INTVEC0_START = 0x802FE000;
LCF_INTVEC1_START = 0x805FE000;
LCF_INTVEC2_START = 0x808FE000;
LCF_INTVEC3_START = 0x80BFE000;
LCF_INTVEC4_START = 0x80EFE000;
LCF_INTVEC5_START = 0x80FFE000;

__INTTAB_CPU0 = LCF_INTVEC0_START;
__INTTAB_CPU1 = LCF_INTVEC1_START;
__INTTAB_CPU2 = LCF_INTVEC2_START;
__INTTAB_CPU3 = LCF_INTVEC3_START;
__INTTAB_CPU4 = LCF_INTVEC4_START;
__INTTAB_CPU5 = LCF_INTVEC5_START;

LCF_TRAPVEC0_START = 0x80000100;
LCF_TRAPVEC1_START = 0x80300000;
LCF_TRAPVEC2_START = 0x80600000;
LCF_TRAPVEC3_START = 0x80900000;
LCF_TRAPVEC4_START = 0x80C00000;
LCF_TRAPVEC5_START = 0x80F00000;

LCF_STARTPTR_CPU0 = 0x80000000;
LCF_STARTPTR_CPU1 = 0x80300100;
LCF_STARTPTR_CPU2 = 0x80600100;
LCF_STARTPTR_CPU3 = 0x80900100;
LCF_STARTPTR_CPU4 = 0x80C00100;
LCF_STARTPTR_CPU5 = 0x80F00100;

LCF_STARTPTR_NC_CPU0 = 0xA0000000;
LCF_STARTPTR_NC_CPU1 = 0xA0300100;
LCF_STARTPTR_NC_CPU2 = 0xA0600100;
LCF_STARTPTR_NC_CPU3 = 0xA0900100;
LCF_STARTPTR_NC_CPU4 = 0xA0C00100;
LCF_STARTPTR_NC_CPU5 = 0xA0F00100;

RESET = LCF_STARTPTR_NC_CPU0;

[KB · Accepted solution]

Hello E-John,

The below address is used to store the first application start-up instruction "__START"
LCF_STARTPTR_CPU0 = 0x80000000; //for Cached region
LCF_STARTPTR_NC_CPU0 = 0xA0000000; // for non-cached region

The boot software pass the control to Application Startup(based on bmhd_0_orig.stad configuration) placed at location "__START". The application start-up "__START" uses 32bytes
(cached: 0x80000000 - 0x80000020 & non-cached: 0xA0000000 - 0xA0000020).
That's why the Trap table is moved to address LCF_TRAPVEC0_START = 0x80000100(nearest 256 bit aligned location).

As for cores other than core 0, for example, the core 0 sets PC(Program Counter) of core 1 to __START1(refer core 0's __StartUpSoftware_Phase6)instead of boot software.
The __START1 is at LCF_STARTPTR_NC_CPU1 = 0xA0300100 (for cached LCF_STARTPTR_CPU1 = 0x80300100), hence the trap table can be safely be placed at 0x80300000 (256 bit aligned).

Regards,

KB

[E-John]

Hi KB,

It is clear.

Thanks for your explanations and helps.

[E-John]

Hi KB,

The boot software pass the control to Application Startup(based on bmhd_0_orig.stad configuration) placed at location "__START". The application start-up "__START" uses 32bytes
(cached: 0x80000000 - 0x80000020 & non-cached: 0xA0000000 - 0xA0000020).
That's why the Trap table is moved to address LCF_TRAPVEC0_START = 0x80000100(nearest 256 bit aligned location).

Is there any documentation or code for reference about "The application start-up "__START" uses 32bytes"? thanks.

[KB]

Hello E-John,

Since _START is application start-up which is user-specific, its upto the user to decide the size of _START.

However in iLLD example codes, the user-specific start-up function "_START" is placed in the section "reset". If you refer the .lsl file this section is allocated with 0x20 bytes.

You can also refer map file to get the space allocation related information.

Regards,

KB