EDMA Error: init: Failed to open /dev/mem: 'Operation not permitted'

Ashwani

hi all ,

I am trying to play a mp4 media file using OMX hardware plugins.we got
some problem ,the video is not playing .

I am posting the few lines of CE debug messages and attaching complete CE debug messages.

I//system/bin/mediaserver( 1707): @2,083,678us: [+0 T:0x00083d18 S:0x406174ac] ti.sdo.fc.edma3 - EDMA3_getResourceManager> Enter (alg=0x4061a000, scratchId=0)
I//system/bin/mediaserver( 1707): @2,084,788us: [+2 T:0x00083d18 S:0x406174ac] ti.sdo.fc.edma3 - EDMA3_getResourceManager> First time handle is requested, create Resource Manager object
I//system/bin/mediaserver( 1707): @2,085,026us: [+0 T:0x00083d18 S:0x40617484] ti.sdo.fc.edma3 - EDMA3_createResourceManagerObject> Enter

I//system/bin/mediaserver( 1707): EDMA Error: init: Failed to open /dev/mem: 'Operation not permitted'

I//system/bin/mediaserver( 1707): @2,096,554us: [+7 T:0x00083d18 S:0x40617484] ti.sdo.fc.edma3 - EDMA3_createResourceManagerObject> Failed to initialize ti.sdo.fc.linuxutils.edma module.
I//system/bin/mediaserver( 1707): @2,096,837us: [+7 T:0x00083d18 S:0x406174ac] ti.sdo.fc.edma3 - EDMA3_getResourceManager> Resource Manager object could not be created.
I//system/bin/mediaserver( 1707): @2,106,335us: [+7 T:0x00083d18 S:0x406174d4] ti.sdo.fc.ires.edma3Chan - IRESMAN_EDMA3CHAN_getHandles> Error obtaining Low level Resource Manager Handle.
I//system/bin/mediaserver( 1707): @2,106,578us: [+0 T:0x00083d18 S:0x406174d4] ti.sdo.fc.ires.edma3Chan - IRESMAN_EDMA3CHAN_getHandles> Exit (handle=NULL, status=IRES_ENORESOURCE.

able to play the mp4 file using Gstreamer pipelines under the same.

can anyone help me whats going wrong incase of Openmax hardware
plugins ?any help is appreciated.

over 14 years ago

0 Robert Tivy over 14 years ago

TI__Mastermind 18260 points

The simplest reason would be that you don't have the correct permissions for /dev/mem. Are you running the app as "root"? It could be that you are not and only "root" has the necessary permissions.

Regards,

- Rob

0 Ashwani over 14 years ago in reply to Robert Tivy

Expert 1365 points

I am working on android platform. I have run the application as root user(#su root). I have given full permission to /dev/mem but getting the same messages.

Any suggestion would be very appreciated.

0 Ashwani over 14 years ago in reply to Ashwani

Expert 1365 points

After changing the permission, Its working.

Thanks

0 Xiaogang Li over 14 years ago in reply to Ashwani

Prodigy 20 points

What `permission' you've changed, could you give me some tips?

Thanks.

0 Ashwani over 14 years ago in reply to Xiaogang Li

Expert 1365 points

I have run the application as root user(#su root) and given full permission to /dev/mem.

0 Xiaogang Li over 14 years ago in reply to Ashwani

Prodigy 20 points

Got it.

And I figured out my question:

Early kernel let userspace utils read&write physical memroy via mmap and /dev/mem.

but it changed to be strict, if sudo cat /dev/mem > mem, only 1M.

CONFIG_X86_PAT and CONFIG_STRICT_DEVMEM are defaultly set to `y'.

Get to `n' then recompile, works again.

Regards,

0 Rex Su over 13 years ago in reply to Xiaogang Li

Prodigy 10 points

Hi,

I am facing the same issue. I have checked my config file, the CONFIG_STRICT_DEVMEM is set to n. But I still have no luck getting an application to work with /dev/mem

I wrote a user space C native program which can access /dev/mem, but when I put the same code into JNI it says " Failed to open /dev/mem: 'Operation not permitted'"

Since there are at least two members who got this to work, would someone explain how you managed to run an application as root to get /dev/mem working?

Does it require modifying the application JAVA source code to gain root permissions? Thanks

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EDMA Error: init: Failed to open /dev/mem: 'Operation not permitted'