Processor SDK Big Data IPC Examples

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RTOS Software Developer Guide Big Data IPC Examples


High Performance Computing applications and other Data intensive applications often require passing of Big data buffers between the multi-core processors in an SOC.

The Big Data IPC examples are created mainly to show exchange of big data buffers between cores and is part of the Processor SDK RTOS package.

Currently the example named "simple_buffer_example", captures the details of exchange of big buffers with both host A15 core and a DSP cores.

Architecture Overview

The following block diagram shows the various functional blocks used in the example on the cores running TI-RTOS/BIOS.

Big Data IPC RTOS Software blocks.png

For the small message IPC, sharedRegion and Heap, the modules in the Standard TI IPC package are used.

The BigDataXlat module, which is part of the example code, provides a high level abstraction to take care of Address translation and Cache sync on the big data buffers.

Simple Buffer example: Program Sequence

This section describes the program sequence captured in the example.

The main aim of the overall program is to show the exchange of big data buffers. The sequence is described in words here to sort of walk through the main application code.

Initially, the host sends first message with shared memory init information followed by two more dummy messages to slave core ( all three messages sent in sequence without waiting for reply).

The shared memory region init message conveys the details about the shared memory expected to hold the big data buffers.

Independently, the slave processor receives messages and sends back reply back for each of the messages to the host.

Then the host receives one message from the slave and sends a message with Big data buffer allocated from the Big data heap and filled with an incrementing pattern. (This process is repeated with 10 Big data Buffer messages). Each of these Messages are received by slave and the values in the buffers are updated with a modified incrementing pattern and sent back to the host.

Note the Slave and Host processors checks the expected incrementing pattern for errors.

At this point only 7 Big data buffer messages would have been received. Then the host sends two dummy messages plus one shutdown message to the slave core when receiving the remaining three Big data buffer messages. Totally 10 Big data buffers are exchanged between the cores. The slave core on receiving the shutdown message, shuts itself down and reinitializes itself for future runs.

Then the host receives back the remaining returned messages before shutting down.

NOTE: The size of the big data buffer is configurable compile time by changing value of the define BIGDATA_SIZE in shared/AppCommon.h

Host Linux example

!!! CAUTION !!! This section is under construction

NOTE: Host linux example is only available starting from Processor SDK 4.0.0 release for AM57xx platform

Under the host_linux directory the simple_buffer_example is implemented for Host A15 running Linux and DSP core running TI-RTOS.

Architecture Updates for Linux

The following block diagram shows the various functional blocks used in the example on the host running linux.

Big DATA IPC Linux Software blocks.png

The SharedRegion and HeapMem modules are not currently supported for Linux in the TI Standard IPC package.

The example provides these modules with same/similar API implemented for Linux with some limitations.

The CMEM APIs provide user space allocation of contiguous memory for the Big data buffers.

How to Run the Example

The Processor SDK Linux release includes the pre-built binaries for the host_linux example as part of the tisdk-rootfs-image filesystem.

Step 1 : To run the demo, the first step is to make sure there is no other default applications using the same resources. For example, the following command is needed to disable the default OpenCL applications.

   systemctl stop ti-mct-daemon.service    	

Step 2: Switch the firmware running in the DSP. This can be done by using the following steps. Unbind dsp

   echo 40800000.dsp > /sys/bus/platform/drivers/omap-rproc/unbind

NOTE: May need to unbind all the other cores as well to avoid issues.

Update firmware symbolic link

   ln -sf /usr/bin/simple_buffer_example/release/server_dsp.xe66 /lib/firmware/dra7-dsp1-fw.xe66

Bind dsp

   echo 40800000.dsp > /sys/bus/platform/drivers/omap-rproc/bind

Step 3: Now the Host side application can be run using the following command


The DSP side log can be checked by typing the following command to dump the trace.

   cat /sys/kernel/debug/remoteproc/remoteproc2/trace0

Here is a sample log.

root@am57xx-evm:~# /usr/bin/simple_buffer_example/release/app_host DSP1
--> main:
[523682.897761] omap_hwmod: mmu0_dsp2: _wait_target_disable failed
[523682.903751] omap-iommu 41501000.mmu: 41501000.mmu: version 3.0
[523682.911797] omap-iommu 41502000.mmu: 41502000.mmu: version 3.0
--> Main_main:
--> App_create:
App_create: Host is ready
<-- App_create:
--> App_exec:
CMEM_init success
CMEM_getPool success
CMEM_allocPool success: Allocated buffer 0xaa641000
SharedRegion_setup success
App_taskFxn: SR_1, base 0xaa641000, len=1000000
HeapMem_setup success
HeapMem_create success
App_taskFxn: SR_1 heap, totalSize=16777216,totalFreeSize=16777216,largestFreeSize=16777216
App_taskFxn: SR_1 heap, buf=0x0xaa641080,size=16777216
App_exec: sending message 1
Shared memory phys Addr ffffffffa0000000
App_exec: sending message 2
App_exec: sending message 3
App_exec: message received 1
App_exec: Preparing message 4
App_exec: Sending message 4
App_exec: message received 2
App_exec: Preparing message 5
App_exec: Sending message 5
App_exec: message received 3
App_exec: Preparing message 6
App_exec: Sending message 6
App_exec: message received 4
App_exec: Preparing message 7
App_exec: Sending message 7
App_exec: message received 5
App_exec: Preparing message 8
App_exec: Sending message 8
App_exec: message received 6
App_exec: Preparing message 9
App_exec: Sending message 9
App_exec: message received 7
App_exec: Preparing message 10
App_exec: Sending message 10
App_exec: message received 8
App_exec: Preparing message 11
App_exec: Sending message 11
App_exec: message received 9
App_exec: Preparing message 12
App_exec: Sending message 12
App_exec: message received 10
App_exec: Preparing message 13
App_exec: Sending message 13
App_exec: message received 11
App_exec: Preparing message 14
App_exec: Sending message 14
App_exec: message received 12
App_exec: Preparing message 15
App_exec: Sending message 15
App_exec: message received 13
App_exec: Preparing message 16
App_exec: Sending message 16
App_exec: message received: 14
App_exec: message received: 15
App_exec: message received: 16
App_exec: Data check clean
<-- App_exec: 0
--> App_delete:
<-- App_delete:
<-- Main_main:

 Host: Test Passed 
<-- main:

root@am57xx-evm:~# cat /sys/kernel/debug/remoteproc/remoteproc2/trace0 
[      0.000] 18 Resource entries at 0x95000000
[      0.000] [t=0x0002122e] xdc.runtime.Main: --> main:
[      0.000] registering rpmsg-proto:rpmsg-proto service on 61 with HOST
[      0.000] [t=0x003c5d7b] xdc.runtime.Main: NameMap_sendMessage: HOST 53, port=61
[      0.000] [t=0x003d5186] xdc.runtime.Main: --> smain:
[      0.000] [t=0x003e8259] Server: Server_create: server is ready
[      0.000] [t=0x003ecc97] Server: <-- Server_create: 0
[      0.000] [t=0x003f04a4] Server: --> Server_exec:
[     51.571] [t=0x00000008:a56e6a9a] Server: Message received...1
[     51.571] [t=0x00000008:a56f9b77] Server: Shared region entry configured...
[     51.571] [t=0x00000008:a5700cb1] Server: Server_exec: processed id 1, cmd=0x1
[     51.571] [t=0x00000008:a570aea5] Server: Message received...2
[     51.571] [t=0x00000008:a57119fd] Server: Server_exec: processed id 2, cmd=0x0
[     51.571] [t=0x00000008:a571b1e9] Server: Message received...3
[     51.571] [t=0x00000008:a5721eac] Server: Server_exec: processed id 3, cmd=0x0
[     51.571] [t=0x00000008:a5755f6b] Server: Message received...4
[     51.573] [t=0x00000008:a583e61b] Server: Server_exec: processed id 4, cmd=0x2
[     51.573] [t=0x00000008:a584a087] Server: Message received...5
[     51.574] [t=0x00000008:a592c2cc] Server: Server_exec: processed id 5, cmd=0x2
[     51.574] [t=0x00000008:a5937d8c] Server: Message received...6
[     51.575] [t=0x00000008:a5a19aeb] Server: Server_exec: processed id 6, cmd=0x2
[     51.575] [t=0x00000008:a5a2543d] Server: Message received...7
[     51.577] [t=0x00000008:a5b07d15] Server: Server_exec: processed id 7, cmd=0x2
[     51.577] [t=0x00000008:a5b137c0] Server: Message received...8
[     51.578] [t=0x00000008:a5bf5d83] Server: Server_exec: processed id 8, cmd=0x2
[     51.578] [t=0x00000008:a5c019cc] Server: Message received...9
[     51.579] [t=0x00000008:a5ce3dca] Server: Server_exec: processed id 9, cmd=0x2
[     51.579] [t=0x00000008:a5cef75e] Server: Message received...10
[     51.581] [t=0x00000008:a5dd247a] Server: Server_exec: processed id 10, cmd=0x2
[     51.581] [t=0x00000008:a5dde2d9] Server: Message received...11
[     51.582] [t=0x00000008:a5ec04df] Server: Server_exec: processed id 11, cmd=0x2
[     51.582] [t=0x00000008:a5ecc1a3] Server: Message received...12
[     51.583] [t=0x00000008:a5fae91c] Server: Server_exec: processed id 12, cmd=0x2
[     51.583] [t=0x00000008:a5fba4c6] Server: Message received...13
[     51.585] [t=0x00000008:a609d1c1] Server: Server_exec: processed id 13, cmd=0x2
[     51.585] [t=0x00000008:a60a8dd4] Server: Message received...14
[     51.585] [t=0x00000008:a60af96e] Server: Server_exec: processed id 14, cmd=0x0
[     51.585] [t=0x00000008:a60b9229] Server: Message received...15
[     51.585] [t=0x00000008:a60bffd3] Server: Server_exec: processed id 15, cmd=0x0
[     51.585] [t=0x00000008:a60e179b] Server: Message received...16
[     51.585] [t=0x00000008:a60e9727] Server: Server_exec: processed id 16, cmd=0x2000000
[     51.585] [t=0x00000008:a60f3fb7] Server: Server_exec: Data check clean
[     51.585] [t=0x00000008:a60fb280] Server: <-- Server_exec: 0
[     51.585] [t=0x00000008:a6101708] xdc.runtime.Main: DSP: Test Passed
[     51.585] [t=0x00000008:a6109170] Server: --> Server_delete:
[     51.585] [t=0x00000008:a6114fa2] Server: <-- Server_delete: 0
[     51.586] [t=0x00000008:a6127d48] Server: Server_create: server is ready
[     51.586] [t=0x00000008:a612ff93] Server: <-- Server_create: 0
[     51.586] [t=0x00000008:a613620c] Server: --> Server_exec:

How to Re-Build the example

Also source code for the example is included in the Processor SDK Linux release. Once installed the source files can be found in the directory example-applications/big-data-ipc-demo-linux_<version>.

Prerequisites: Need to have the Processor SDK Linux release installed to build the DSP side RTOS image. See the instruction in RTOS SDK Getting Started Guide

The example can be rebuilt by using the following commands.

   make big-data-ipc-demo

The test binaries can be installed into the default filesystem using the command.

   make big-data-ipc-demo_install

Note: Rules.make file can be edited to change the DESTDIR where the binaries will be installed.

Source files

The source files for the example are located at


The host directory and dsp directory has the corresponding sources. The shared folder contains some common sources.
The main sequence for big data IPC can be followed by looking at host/App.c and dsp/Server.c.

Memory layout details

The DSP side memory layout can be found in the file host_linux/simple_buffer_example/shared/<platform>/config.bld.

Also note the addition of the following section in host_linux/simple_buffer_example/shared/<platform>/rsc_table_dsp.h.

Please note the reserved carve-out in the DSP resource table /* NOTE: Make sure this matches what is configured in the linux device tree */

  1. define DSP_CMEM_IOBUFS 0xA0000000
  2. define PHYS_CMEM_IOBUFS 0xA0000000
  3. define DSP_CMEM_IOBUFS_SIZE (SZ_1M * 192)

The CMEM area allocated from this region is used for the big data buffers.

Host RTOS example

Under the host_bios directory the simple_buffer_example is implemented for Host A15 and DSP both running TI RTOS/BIOS.

How to Run the Example

The Processor SDK RTOS release include the pre-built binaries for the host_bios example under:


Also for the platforms that support boot through SDcard, pre-built boot image or 'app' bootable through SBL is located under:


AM57xx & K2G boards


1. Create a bootable SDCard using the procedure here:

2. Connect the UART on the hardware to the Host.
( Configure the terminal/console to Baud Rate= 115200, Data Bits= 8 , Parity= None, Flow Control= Off )


  • Copy/overwrite the pre-built boot image 'app' corresponding to the board to a bootable SD Card
  • Insert the SD card into the board
  • Boot/Reboot the board

The application will be loaded and run automatically and the "Host: Test Passed" message will be printed to the UART console.

BigDataIPC Rtos Demo.png

K2H, K2K, K2L, K2E Boards

The prebuilt elf binaries of Host and DSP images can be loaded through CCS to the appropriate cores and run.

How to Re-Build the Example

The bigdata ipc examples can be built from the Processor SDK top level directory using the following steps

1. Build environment setup

Linux host

   cd  <processor_sdk_<platform>_<version>
   export SDK_INSTALL_PATH=<Base directory where Processor SDK is installed>

Windows host

   cd  <processor_sdk_<platform>_<version>
   set SDK_INSTALL_PATH=<Base directory where Processor SDK is installed>

2. Build

   make bigdataipc_examples

This creates the elf binaries for both the host and DSP cores.
And the binaries can be installed using

   make bigdataipc_examples_install

(NOTE: The above command installs the elf binaries under the prebuilt-binaries location mentioned above.
Need to convert the prebuilt elf binaries into bootable images refer to )

Source files

The source files for the example are located at


The host directory and dsp directory has the corresponding sources. The shared folder contains some common sources.
The main sequence for big data IPC can be followed by looking at host/App.c and dsp/Server.c.