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AD7476A Pmod Xilinx FPGA Reference Design can`t works

Question asked by huanmolb@163.com on Nov 20, 2015
Latest reply on Nov 20, 2015 by larsc

Hello guys,I have a zedboard kit and a pmod_ad1, I `m studying use the zed,and I follow the refrence design Linux Device Driver - Custom HDL PCore ,I follow the guid ,and there`s some unimportant difference (use u-boot 15.0 ,kernel 4.0 ,devicetree_pmod_ad1_ipcore.all of this is download from analogdevice git). when I download all files to SD card and turn on zed,the hdmi ,usb works well ,The IIO scope devices list shows the two channel of AD7476, but when I turn on the channel ,system will be get stuck, and terminal shows  Unable to handle kernel NULL pointer dereference at virtual address 00000000, and oops tells NULL pointer,

PC is at 0x0

LR is at iio_buffer_data_available+0x10/0x14

 

I check the iio driver and find nothing usefull, I think I need some help, Thanks

 

    

Unable to handle kernel NULL pointer dereference at virtual address 00000000

pgd = d6ab0000

[00000000] *pgd=16810831, *pte=00000000, *ppte=00000000

Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM

Modules linked in:

CPU: 1 PID: 1736 Comm: hexdump Not tainted 3.17.0 #1

task: df76a940 ti: df660000 task.ti: df660000

PC is at 0x0

LR is at iio_buffer_data_available+0x10/0x14

pc : [<00000000>]    lr : [<c03193b4>]    psr: a0030013

sp : df661f20  ip : c031a424  fp : 00015120

r10: 00001000  r9 : df660000  r8 : b6fa4000

r7 : df661f88  r6 : d6802280  r5 : df6d0800  r4 : df5b34c0

r3 : 00000000  r2 : 00001000  r1 : c045974c  r0 : df5b34c0

Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user

Control: 18c5387d  Table: 16ab004a  DAC: 00000015

Process hexdump (pid: 1736, stack limit = 0xdf660240)

Stack: (0xdf661f20 to 0xdf662000)

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