NIOS + MMU uClinux + PIO

Hi,

I am searching for the same thing for a while.

I probably found a solution. Perhaps this might come handy:

http://alteraforums.org/forum/showthread.php?p=67792

I don't have the time to test it now, but I will tomorrow.

Urmel

Update:

Now I can set things like LED.

All you have to do is write a c program, i.e. "ledtest.c"

/* ledtest.c*/# include <stdio.h># include <asm/io.h>
// if you like you can also include the header file with your base addresses of the board
# define LED0 0x06 //the hex address for my first LED
int main(void)
{
  // ... my html code
  outl(LED0, LED_BASE) /* the first parameter of 'outl' is the value you want to set. The second is the base_address of the hardware you want to control. Either insert it manually or take the address from your included header file*/
 return 0;
}

But the most important part is the makefile.

I took it from the generic-cgi folder and modified it to my needs.

You have to add 'O2' to the flags otherwise the header file can't be found.

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Update:

Now I can set things like LED.

All you have to do is write a c program, i.e. "ledtest.c"

/* ledtest.c*/
# include <stdio.h>
# include <asm/io.h>
// if you like you can also include the header file with your base addresses of the board
# define LED0 0x06 //the hex address for my first LED
int main(void)
{
  // ... my html code
  outl(LED0, LED_BASE) /* the first parameter of 'outl' is the value you want to set. The second is the base_address of the hardware you want to control. Either insert it manually or take the address from your included header file*/
 return 0;
}

But the most important part is the makefile.

I took it from the generic-cgi folder and modified it to my needs.

You have to add 'O2' to the flags otherwise the header file can't be found.

--- Quote End ---

This will only work without MMU. And -O2 means optimize, it has nothing to do with what files are included.

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This will only work without MMU. And -O2 means optimize, it has nothing to do with what files are included.

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I have only worked on a version without MMU so I didn't knew that this wouldn't work. But good to know for the future.

Ah damn, you are right with the optimize flag 'O2'. I knew it was for optimization but I also thought it was for proper including the right header files. But one of the flags '-o' or '-O2' is sufficient.

But the reason why I couldn't include the asm/io.h was a failure in my own Makefile. The Makefile from the cgi_generic works.

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This will only work without MMU. And -O2 means optimize, it has nothing to do with what files are included.

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How to controll LEDs or PIO buttons on Linux with MMU?

Now I learned how to use LEDS or Buttons with NIOS MMU. This is quite simple with writing modules for kernel. This is simple one:

# include <linux/init.h>
# include <linux/module.h>
# include <linux/kernel.h>
# include <asm/io.h>
MODULE_LICENSE("GPL");
static void* ledg_vadd;
static void* ledr_vadd;
static int __init hello_init(void)
{
printk(KERN_ALERT "Hello, world\n");
ledg_vadd = ioremap(LEDS_G, 16);
ledr_vadd = ioremap(LEDS_R, 16);
if(ledg_vadd == NULL) {
  printk(KERN_ALERT "Adress is NULL");
  return 0;
}
else {
  printk(KERN_INFO "Address LEDS_G is 0x%p\n", ledg_vadd);
}
if(ledr_vadd == NULL) {
  printk(KERN_ALERT "Adress is NULL");
  return 0;
}
else {
  printk(KERN_INFO "Address LEDS_R is 0x%p\n", ledr_vadd);
}
writeb(13, ledg_vadd);
writeb(15, ledr_vadd);
return 0;
}
static void __exit hello_exit(void)
{
printk(KERN_ALERT "Goodbye, cruel world\n");
writeb(3, ledg_vadd);
writeb(2, ledr_vadd);
iounmap(ledg_vadd);
iounmap(ledr_vadd);
}
module_init(hello_init);
module_exit(hello_exit);