mmap local APIC address

[Vaibhav Jain]

Hi,

Please ignore the email below. I am sorry I  made a very silly mistake.

Thanks
Vaibhav Jain

On Wed, Oct 19, 2011 at 10:12 AM, Vaibhav Jain <vjoss197 at gmail.com> wrote:

> On Fri, Oct 14, 2011 at 9:10 PM, Mulyadi Santosa <
> mulyadi.santosa at gmail.com> wrote:
>
>> hi...
>>
>> On Sat, Oct 15, 2011 at 07:22, Vaibhav Jain <vjoss197 at gmail.com> wrote:
>> > Hi,
>> >
>> > I am trying to map local APIC on an intel system (physical address
>> > 0xfee00000) in a user level program using mmap
>> > but my mmap is failing saying "Bad file descriptor". I am not sure if
>> this
>> > problem is related to apic or
>> > mmap. I am running the program as root.  Please help me figure this out.
>>
>> could you post the code?
>>
>> anyway, check "man mmap" in "errors" section....the hint could be
>> found there.....
>>
>> --
>> regards,
>>
>> Mulyadi Santosa
>> Freelance Linux trainer and consultant
>>
>> blog: the-hydra.blogspot.com
>> training: mulyaditraining.blogspot.com
>>
>
>
> Hi,
>
> Here's the code
>
>
>
> typedef unsigned int u32;
>
> #define MAP_LEN                 0x1000  //4 KB page
> #define BUFLEN 100
> *#define APIC_BASE               0xfee00000*
> #define APIC_ICR_low            0xfee00300
> #define APIC_ICR_high           0xfee00310
> #define APIC_ICR_init           0x00000500
> #define APIC_ICR_start          0x00000600
> #define APIC_ICR_ASSERT_LVL_TRG 0x0000c000
> #define BOUNCE_CODE        0x2000
>
> int apic_reset_cpu(cpu);
> int cpu = 2;
>
> int main(){
> if ((apic_reset_cpu(cpu)) != 0)
>     printf("INIT & Startup failed!\n");
> }
>
>
> int apic_reset_cpu(int cpu)
> {
>   unsigned long tmpaddress, apic_icr, *apic_phy_addr;
>   int fd, sleep_now=0;
>
>
>   printf("Assuming APIC physical base: %lx \n", APIC_BASE);
>   tmpaddress = (unsigned long) mmap(NULL, MAP_LEN, PROT_READ|PROT_WRITE,
> MAP_SHARED, fd, (off_t)APIC_BASE);
>
> *  if(tmpaddress == (unsigned long)MAP_FAILED) //check if it worked
>   {
>     perror("Mapping memory for absolute memory access failed.\n");
>     return -3;
>   }*
>
>   //prep ICR high
>   apic_icr = tmpaddress;
>   apic_icr |= APIC_ICR_high;
>   apic_phy_addr = (unsigned long *) apic_icr;
>   *apic_phy_addr = cpu << 24;
>
>   //prep ICR low Send INIT and wait
>   apic_icr = tmpaddress;
>   apic_icr |= APIC_ICR_low;
>   apic_phy_addr = (unsigned long *) apic_icr;
>   *apic_phy_addr = APIC_ICR_init | APIC_ICR_ASSERT_LVL_TRG;
>   sleep_now = usleep( 10000 ); //sleep 10 ms
>
>   //prep for SIPI
>   apic_icr = tmpaddress;
>   apic_icr |= APIC_ICR_low;
>   apic_phy_addr = (unsigned long *) apic_icr;
>   *apic_phy_addr = APIC_ICR_start | (BOUNCE_CODE >> 12);
>   sleep_now = usleep( 500 ); //sleep 500 usec
>
>   printf("Unmapping APIC Base page\n");
>   tmpaddress &= 0xfffff000;
>   munmap(tmpaddress, MAP_LEN);
>
>   return 0;
> }
>
> Thanks
> Vaibhav Jain
>
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