SGI in arm

[saida]

hi

can any one help how to do inter processor communication using SGI in arm, possibly with code

i am able to generate sgi independently to each core but i am unable to generate interrupt to other core using sgi

how can i do this ?

regards

saida

[igorpadykov]

Hi Saida

please look at attached baremetal gpio interrupt example in interrupt.c

setup_interrupts_in_RAM()

~igor

[saida]

Hi igorpadykov

May be this works

Before that i tried with Changing Vector Base address to my vectors address in CP15 Register which is working fine

can i follow this or is it mandatory to locate ROM vectors to iRAM and write our routine to ram location.

I think in Startup.s code of SDK is doing copying of Vectors to iRAM location but its not working why ?

if i check memory view of iRAM in DS-5 Debugger, my IRQ_Handler is not mapped to memory location 0x91fff4.

Finally i Need Your Help  to these tasks

1. My sabresd board unable to connect in multicore debugginrg (debugg configuration of DS-5 i selected Cortex-A9x2 SMP connection) it was showing "your debugger is unable to connect"

2. is MMU required for Baremetal application with this two cores running in SMP mode ?

and what are the minimum initialization required to run these two cores for my application

i really Thank you  for your immediate response for my quiries

Regards

Saida

[igorpadykov]

Hi Saida

example SGI can be found in attached document from SDK

sect.4.4.6 Using software generated interrupts (SGIs).

Also sect.4.4.11 GIC "hello world" example, with one core completes

the main routine, it triggers the SGIn interrupt to another core.

Best regards

igor

[saida]

hi igorpadykov

thank you for your reply

i am giving the code what i am trying

i have done what you suggested, still its not working

i am debugging with DS5 in single core0 mode.( my debugger is not connecting in SMP mode )

i have some doughts

1) with out cpu init also SGI works right ,if already GIC initialized to other cores

     example:

          core0

          1. gic init

          2. cpu_init

          3. register interrupt routine

          4. enable interuupt(id,priority,cpu)

          core1

          1. SGI to core0 i think its works fine

2) some times its working but some times its not i dont what is the problem

3) why my debugger unable to connect in SMP mode

include "sdk.h"

#include "platform_init.h"

#include "timer.h"

#include "cpu_utility.h"

#include "cortex_a9.h"

#include "MP_Mutexes.h"

#define DUALCORE

//#undef DUALCORE

#define CHIP_MX6SDL

int gicTestDone;

void my_isr(void)

{

    int cpu_id;

    cpu_id = cpu_get_current();

    my_string("Hello from core ");

    print_cpu_id();//id no

    if(cpu_id == 0)

    gic_send_sgi(SW_INTERRUPT_3, 2, kGicSgiFilter_UseTargetList);//interrupt to core1

    if(cpu_id == 1)

    {

    gicTestDone=0;

    up=0;

    }

}

// Set MAX_CPUS as desired; will be forced to no greater than actual number of cpus.

#define MAX_CPUS 2;

static unsigned int num_cpus = MAX_CPUS;

void configure_cpu(uint32_t cpu)

{

    const unsigned int all_ways = 0xf;

    disable_strict_align_check();

    // Enable branch prediction

    arm_branch_target_cache_invalidate();

    arm_branch_prediction_enable();

    // Enable L1 caches

    arm_dcache_enable();

    arm_dcache_invalidate();

    arm_icache_enable();

    arm_icache_invalidate();

    // Invalidate SCU copy of TAG RAMs

    scu_secure_invalidate(cpu, all_ways);

    // Join SMP

    scu_join_smp();

    scu_enable_maintenance_broadcast();

}

void obc_main(void * arg)

{

    uint64_t start_time, done_time;

    uint32_t cpu_id = cpu_get_current();

    int i;

    if (cpu_id == 0)

    {

        int cpu_count = cpu_get_cores();

        gicTestDone = 1;

           register_interrupt_routine(SW_INTERRUPT_3, my_isr);// register interrupt

           enable_interrupt(SW_INTERRUPT_3, CPU_0, 0);//enable int

        if (num_cpus > cpu_count)

        {

            num_cpus = cpu_count;

        }

        scu_enable();

        configure_cpu(cpu_id);

    /* secondary cores starting */

        for (i = 1; i < num_cpus; i++)

        {

            cpu_start_secondary(i, &obc_main, 0);

        }

        while (gicTestDone)

        {

            my_string("END of GIC Test \n\r");

        }

    }

    else

    {

        configure_cpu(cpu_id);

        gic_init_cpu();//init CPU interface

        //gic_init();

       int core1_cpsr;

        __asm{mrs core1_cpsr,cpsr}

        core1_cpsr &= 0xffffff7f;//set CPSR I bit

          __asm{msr cpsr_c,core1_cpsr}

          enable_interrupt(SW_INTERRUPT_3, CPU_1, 0);

          gic_send_sgi(SW_INTERRUPT_3, 1, kGicSgiFilter_UseTargetList);

          while(1);

    }

}

void main(void)

{

    platform_init();

    obc_main(0);

}

if you find any errors please give me the corrections

in my custom board i am distributing routines to both the cores for bare-metal applpication in SMP code

this code  i have taken from SMP_PRIMES from SDK and modified according to my application

with out GIC both the cores working fine with some printf with mutex

please give reply as soon as possible

thank you

regards

Saida

[saida]

hi igopadykov

i found that it is problem of vector table mapping

one time interrupt is service but not next time

i am checking with epit time in continuous interrupt routine

can you tellme  how exactly this ram vector table mapped ? and how can i verify that is correctly mapped with help of debugger

i am using from sdk startup code