Re: Thanks a lot

Hello Prashant,

> Hello Dieter, 
> 
> Thanks a lot for the way you suggested. I sas the file. 
> It seems to be useful.Due to problems in my mail account, I cudn't reply
> you earlier. Kindly excuse me for that. 
> 
> Before reading your mail, I wrote a code to test external interrupt.
> the code is expected to print "I am in main", till a switch, connected
> to IRQ1, is not pressed. As soon as it is pressed, it should print
> "Hello from Interrupt". 

Some snippets how your code works where helpful :)

         
> when i run this code, it shows "I m in main" untill i press IRQ1 switch.
> As soon as I press IRQ1 Switch, it shows me following message
>         
>         irq 34376, desc: c0206c40, depth: 0, count: 0, unhandled: 0
>         ->handle_irq():  c0053edc, handle_bad_irq+0x0/0x1f4
>         ->chip(): 00000000, __init_begin+0x3fff8000/0x30
>         ->action(): 00000000

Do you have a own kernel module which does interrupt handling?
I fear as long as there are not more information it would be hard to help you.


Dieter

         
>         
> and then it starts to send "I m in main" again. 
> 
> I request you to suggest me what may be the problem.
> I'll be highly oblized. 
>  
> 
> With Thanks and Best Regards, 
> Prashant Sangal
> 
> 
> 
> Author: Dieter Kiermaier
> Date: 2009-07-10 11:312009-07-10 06:01 +5.530UTC
> To: prashant sangal
> CC: linux-arm
> Subject: Re: Interrupt problem
> 
> Hi Prashant, 
> 
> > Hello Dieter, 
> > 
> > I am also not very much experienced on linux. Your idea may work, but
> i don't know how to use sysfs. 
> > Can you please elaborate it? 
> > 
> 
> You can have a look at Documentation/gpio.txt in the kernel tree. There
> is (hopefully) all what you need. 
> 
> Dieter 
> 
> > With Thanks and Regards, 
> > Prashant Sangal 
> > 
> > 
> > ________________________________ 
> > From: Dieter Kiermaier <[email protected]> 
> > To: [email protected] 
> > Sent: Thursday, 9 July, 2009 9:14:51 PM 
> > Subject: Re: Interrupt problem 
> > 
> > Hi all, 
> > 
> > I'm fairly new to linux and also to this list so please don't hang me
> up if I'm wrong. 
> > But if your board provides gpiolib support it may be more easy to
> access gpios by using the sysfs? 
> > 
> > Cheers, 
> > Dieter 
> > 
> > 
> > > Hello, 
> > > 
> > > I am working on AT91SAM9260 based board. The board is running linux.
> Using mmap, i can access GPIOs. 
> > > I have been trying to access Interrupt controller through mmap, but
> failed. 
> > > Is it possible to access Interrupt controller of processor using
> mmap? what may be alternate way without digging deep into kernel? 
> > > 
> > > Also, I need a better understanding of how linux manages addressing
> of peripherals? For GPIOs, I am using a sample code as basis of my
> application. this sample code has been provided by the board
> manufacturer. The code snippets are as followed: 
> > > 
> > > ---- 
> > > ---- 
> > > #define AT_BASE 0xFFFFF000 
> > > -- 
> > > --- 
> > > static void *piobase; 
> > > static unsigned int* base; 
> > > --- 
> > > --- 
> > > int main() 
> > > { 
> > > static int fd, pagesize; 
> > > int pattern; 
> > > pagesize = getpagesize(); 
> > > fd = open("/dev/mem", O_RDWR); 
> > > piobase = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, fd,
> AT_BASE); 
> > > base = (unsigned int *) piobase + 0x100; 
> > > -------- 
> > > --------- 
> > > 
> > > } 
> > > 
> > > Here i am unable to undersatnd the reason of choosing 0xFFFFF000 as
> AT_BASE, because as per the memory map of AT91SAM960, this particular
> location is assigned to Advanced Interrupt Controller. 
> > > 
> > > With Best Regards, 
> > > Prashant 
> > > 
> > > 
> > > 
> > > Yahoo! recommends that you upgrade to the new and safer Internet
> Explorer 8. http://downloads.yahoo.com/in/internetexplorer/ 
> > > ------------------------------------------------------------------- 
> > > List admin:
> http://lists.arm.linux.org.uk/mailman/listinfo/linux-arm 
> > > FAQ: http://www.arm.linux.org.uk/mailinglists/faq.php 
> > > Etiquette: http://www.arm.linux.org.uk/mailinglists/etiquette.php 
> > > 
> > 
> > 
> > 
> > ------------------------------------------------------------------- 
> > List admin: http://lists.arm.linux.org.uk/mailman/listinfo/linux-arm 
> > FAQ: http://www.arm.linux.org.uk/mailinglists/faq.php 
> > Etiquette: http://www.arm.linux.org.uk/mailinglists/etiquette.php 
> > 
> > 
> > 
> > Looking for local information? Find it on Yahoo! Local
> http://in.local.yahoo.com/ 
> 
> 
> -------------------------------------
> Hi-Tech Gears Limited, Gurgaon, India
> 
> 
> 
> 



-------------------------------------------------------------------
List admin: http://lists.arm.linux.org.uk/mailman/listinfo/linux-arm
FAQ:        http://www.arm.linux.org.uk/mailinglists/faq.php
Etiquette:  http://www.arm.linux.org.uk/mailinglists/etiquette.php