zhemao/interrupt_example

An example of how to use Avalon interrupts on the Cyclone V FPGA

interrupt_example's Issues

how to create a nonblocking read

Hello Mao,
Thank you for a very informative article. Can you please show how to call a read from userspace without being blocked forever?

I have tried this by changing the "wait_event_interruptible" to "wait_event_interruptible_timeout". However, the timeout resolution is only in multiples of 10ms (since one jiffie is 10ms on my system). I am looking for a way to be able to wait for a delay in usecs times frame and then timeout. Is there a way we can add poll method for the sysfs attribute file? Right now, poll always immediately returns.
Thanks
Sierrarun

Is there a way to notify FPGA from ARM Linux just like FPGA does this using interrupt?

Hi,Howard,
Thanks for your tutorials。

I want to transmit high bandwidth stream(up to 400Mbps) between FPGA and ARM. I think DDR3 is a good solution. so FPGA copy data to a trunk of shared memory,after that notify ARM using the interrupt , then ARM read it out.

When ARM transmit data to FPGA using the same way , copy to shared memory , how to notify FPGA in cyclone V?

Another question:
Is there other better solution to archive my request?

Thank you.

Cant install Interrupt example on the Altera SoC Dev board

Hello Howard,

Many thanks for your Cyclone 5 tutorials they have been a great help.

I have been looking at your interrupt example and have successfully run it on the Arrow Sockit board. However I am now trying to run it on the Altera SoC Development board and have run into difficulties.
When I run the command, insmod ./fpga_uinput.ko , I get the error:
Error: could not insert module fpga_uinput.ko: Invalid parameters.

I am using the 14.0 SD card image, provided by Rocketboards.
uname -a
Linux socfpga 3.13.0-00298-g3c7cbb9 #1 SMP Tue Jun 24 09:29:53 MYT 2014 armv7l GNU/Linux
modinfo fpga_uinput.ko
filename: /home/root/fpga_uinput.ko
license: Dual BSD/GPL
depends:
vermagic: 3.13.0-00298-g3c7cbb9 SMP mod_unload ARMv7 p2v8

Unfortunately I have been unable to get any further information about what could be causing the module to fail with Invalid Parameters.

Are you able to shed any light on this?

Many thanks.
Brian

Interrupt

Hi Howard,

What's the difference between what you are doing here and polling? You are going through the loop and constantly checking for the value in the file.

Can this really be considered as interrupt subroutine?

Thanks,

Jack

Cant complie the fpga_uinput.c file,,issues reagarding kernel header files

hi,
i have dwonloaded your example code from github and trying to cross compile the driver module on ubuntu-x86 pc kernel version 3.13 . i am compiling using linaro tool chain arm compiler for altera cycolne v board. my kernel version of board is 3.10.31-ltsi but the make file gives error .says cnt find the /linx/init.h .i even redirected the compiler to the source folder of kernel bt didnt work.please help immediately .please tell as if the kernel location in make file m putting the soruce folder of kernel is that correct or is it some version mismatch issue>???