Share memory problem on DM816x

Amit Porat

Intellectual 270 points

Hi,

We have a problem working with shared memory allocated on the A8, and sent to the cx6dsp to work with.

We allocate the memory with Vsys_allocBuf, region 0, which fill a Vsys_AllocBufInfo bufInfo

typedef struct {

UInt8 *physAddr;
/**< Physical address */

UInt8 *virtAddr;
/**< Virtual address */

UInt32 srPtr;
/**< Shared region Pointer SRPtr */

} Vsys_AllocBufInfo;

we than send the virtAddr to the cx6dsp through system_link to process

The problem is the cx6dsp does not read the memory intended.

how do we translate the address for the cx6dsp to see the same memory?

Do we use the correct function to allocate shared memory?

Thanks

over 11 years ago

0 Badri Narayanan over 11 years ago

TI__Guru 59700 points

virtAddr is Linux user space address and cannot be passed to c674. To send pointer to c674 you should either send the physical address OR convert virtAddr to SrPtr and then translate back to local pointer on c674 from SrPtr.

Refer ti/ipc/SharedRegion.h for SharedRegion APIs.

0 Amit Porat over 11 years ago in reply to Badri Narayanan

Intellectual 270 points

When we transferred the physical address to the c674 it gave segmentation fault.

How do we translate it from physical to c674 readable address?

Should I transfer the SharedRegion_SRPtr?

Do I use this function:

Ptr SharedRegion_getPtr(SharedRegion_SRPtr srptr);

on the c674?

0 Badri Narayanan over 11 years ago in reply to Amit Porat

TI__Guru 59700 points

What is the value of physAddr.If you are writing to buffer from A8 u shuld use virtAddr.Pls share the code snippet for review

0 Amit Porat over 11 years ago in reply to Badri Narayanan

Intellectual 270 points

My bad...

We referenced it on the A8, which caused the segmentation fault.

On the c674x it worked well

Thank you

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Share memory problem on DM816x