Cannot get SIO_STANDARD mode audio streaming to work on OMAP-L137

Hi,

Thanks for your post.

Which TI BIOS PSP package version? Do you see any issues in McASP driver API's? Kindly elloborate more details on the issue.

In which BIOS PSP example are you facing issues?

Thanks & regards,

Sivaraj K

2072.sine_standard.zip

Thanks for your reply Sivaraj. I am trying to do my own example since none of the PSP examples use the SIO_STANDARD model. I forgot to attach the code to the last post, apologies for this, I have attached it to this one.

A lot the code in my example is identical to the PSP audio driver example. I have removed everything related to setting up the input part of the example, with, as far as I can see, only the code for setting up the output remaining. Obviously since I am attempting to use the SIO_STANDARD model with static buffers, I have changed the code to use SIO_put instead of SIO_issue/SIO_reclaim and moved the creation of the SIO stream to the configuration files mentioned.

To be 100% clear though, the McASP output configuration remains identical to the PSP audio example.

To elaborate more on what happens when I debug the program in the attached example, the program does not reach main and so does not execute any of the C code which I have changed. Instead it gets stuck in the function aic31I2cWrite in the file packages/ti/pspiom/platforms/codec/aic31_src/Aic31.c in the PSP drivers source tree. This appears to be due to either me giving the wrong configuration in either of the files build/sine_standard.tcf or build/sine_standard.tci in the source code which I have now attached or a bug in the drivers themselves. Please take a look at the tcf/tci files to see if there are any obvious mistakes.

The package versions that I am using are:

DSP/BIOS 5.41.03.17

PSP drivers 01.30.01

EDMA3 LLD 01.11.00.03

Hi,

Thanks for your post.

There are some constraints and calling context with reference to SIO_put & SIO_get API calls which are below:

• The stream must not be created with attrs.model set to SIO_ISSUERECLAIM. The results of calling

             SIO_put on a stream created for the issue/reclaim model are undefined.

        •    SIO_put cannot be called from a SWI or HWI.

• This API is callable from the program’s main() function only if the stream's configured timeout

            attribute is 0, or if it is certain that there is a buffer available to be returned.

For more details on the above API's, I would recommend you to check section 2.27 SIO_Module API constraints and calling context in the DSP/BIOS API reference guide as below:

http://www.ti.com/lit/ug/spru403s/spru403s.pdf

I also recommend you to refer section 7.3.1, buffer exchange and Fig. 7-3 to know how SIO_get works and there are good examples which explores the basic SIO_functions and it follows the SIO_STANDARD streaming model with static buffer creation. Kindly refer examples 7.5, 7.7 , 7.9, 7.15 & 7.16 in the DSP/BIOS v5.42 user guide as below:

http://www.ti.com/lit/ug/spru423i/spru423i.pdf

http://smartdata.usbid.com/datasheets/usbid/2000/2000-q3/spru403.pdf

Note: If the stream was opened using the SIO_STANDARD streaming model, it should also frees all buffers remaining in the stream. User-held stream buffers should be explicitly freed by the user’s code via SIO_delete(stream). Please refer the example 7-21 from the above doc. for the DEV_Handle structure which has the following parameters:

todevice is used to transfer DEV_Frame frames to the device. In the SIO_STANDARD (DEV_STANDARD) streaming model, SIO_put puts full frames on this queue, and SIO_get puts empty frames here. In the SIO_ISSUERECLAIM (DEV_ISSUERECLAIM) streaming model, SIO_issue places frames on this queue.

fromdevice is used to transfer DEV_Frame frames from the device. In the SIO_STANDARD DEV_STANDARD) streaming model, SIO_put gets empty frames from this queue, and SIO_get gets full frames from here. In the SIO_ISSUERECLAIM (DEV_ISSUERECLAIM) streaming model, SIO_reclaim retrieves frames from this queue.

Addition references for DSP/BIOS FAQ's and Debugging tips are as below:

http://processors.wiki.ti.com/index.php/DSP_BIOS_FAQ

http://processors.wiki.ti.com/index.php/DSP_BIOS_Debugging_Tips#Cause:_Invoking_BIOS_APIs_from_the_wrong_context

http://www.ti.com/lit/an/spra640a/spra640a.pdf

http://www.ti.com/lit/an/spraa25/spraa25.pdf

Thanks & regards,

Sivaraj K

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To answer the first part of this question regarding the dynamic buffers and SIO_STANDARD, here is a code snippet which shows the method I am now using:

Ptr buffer;
SIO_Handle stream;
DEV_Frame *frame;

// default - SIO_STANDARD, 2 buffers
SIO_Attrs sioAttrs = SIO_ATTRS;

stream = SIO_create( "/dioHandle",
                        SIO_OUTPUT,
                        BUFSIZE,
                        &sioAttrs );

frame = QUE_get( &stream->framelist );
buffer = frame->addr;

for( ... )
{
    // process buffer

    if( SIO_put(stream, &buffer, BUFSIZE) < 0 )
    {
        // handle error
    }
}

Using the above appears to be correct as I now have a working SIO_STANDARD streaming example with dynamic buffers. Note that the initial buffer is found on the framelist of the SIO object, not on the fromdevice as documented. Directly after the SIO_create call, both fromdevice and todevice are empty queues and so looking there does not appear to be the answer.

The function to use to retrieve the buffer is QUE_get, with the result being cast to DEV_Frame pointer. The buffer is then the addr member of the resulting structure.

Note that none of the above is documented anywhere and that all the examples work with static buffers created in the DSP/BIOS configuration. If the above is the correct way to do it, I'm sure this would be very helpful to someone else if something similar was added to the official documentation.

As for the static buffer configuration, as far as I can see the code I have written is consistent will all the above literature and further examples that I found in the DSP/BIOS installation tree. I still have absolutely no idea why it doesn't work.

Hi,

Thanks for your update

According to the above literature documents shared and as per my opinion, the examples should work with static buffers created with DSP/BIOS configuration.

Regards,

Sivaraj K

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Bumping this because I now want to do the same with SIO_get. I have tried the same approach as worked with SIO_put above, but result is that SIO_get hangs. How do you retrieve the initial buffer for use with SIO_get?