PCI express and NIOS

Altera_Forum · ‎11-27-2012

I had a NIOS system working with my custom peripheral this morning on the transceiver starter kit this morning.

I then added a PCI express interface and had to modify the design a bit so I could fit it.

I then recompiled the NIOS and got....

undefined reference to `alt_ic_isr_register'

I see that# define ALT_ENHANCED_INTERRUPT_API_PRESENT is missing from the system.h file for some reason.

Any ideas?

Altera_Forum · ‎11-28-2012

Discovered problem.

It was my fault not really intuitive though.

When I removed the JTAG UART from Qsys and regenerated .sopcinfo

I got the error from eclipse

undefined reference to `alt_ic_isr_register'

Of course the JTAG UART qsys inclusion was generating

# define ALT_ENHANCED_INTERRUPT_API_PRESENT

In the system.h file.

My custom peripheral has no HAL driver and therefore no# _sw.tcl file to indicate enhanced interrupt API and therefore I needed to use legacy interrupts.

What I did was use conditional compilation i.e.

# ifdef ALT_ENHANCED_INTERRUPT_API_PRESENT

static void codec_isr (void *context)

# else

static void codec_isr(void *context, alt_u32 id)

# endif

{

}

And

# ifdef ALT_ENHANCED_INTERRUPT_API_PRESENT

a = alt_ic_isr_register (CODEC_BURST_MASTER_0_IRQ_INTERRUPT_CONTROLLER_ID ,CODEC_BURST_MASTER_0_IRQ, codec_isr, NULL, 0x0);

# else

a = alt_irq_register (CODEC_BURST_MASTER_0_IRQ_INTERRUPT_CONTROLLER_ID ,NULL, codec_isr);

# endif

And of course, using the legacy interrupts, the code now builds.

Let’s see if that will work.