CCS: TDA4M EVM How to get started with SYS/BIOS and UART on C71 DSP?

I tried loading some executables from the pdk like UART_j721e_evm_c7x_1TestApp_release.xe71 via remoteproc on the C71 DSP,

but the remoteproc interface tells me: remoteproc remoteproc2: header-less resource table

There is also an IPC echo test, but the binary for the A72 seems to be a bare-metal binary. I need something running under a POSIX OS.

As you see it is really frustrating to work with the TDA4 at this point. All I want is a small Makefile project for the C71 DSP which uses SYS/BIOS and prints "Hello world" on the UART. Maybe you can just provide me that via ZIP file?

Hi Jan,

Are you trying to load the executables via CCS? I would recommend to try any of the examples in pdk which should be simple enough. To have an idea about what dependencies to include, you can go through the makefiles in any of the examples. I suppose you have already tried this. Please refer to Section 5.5 of the PSDKRA userguide for instructions on loading RTOS binaries to any core.

As i stated in another thread, CCS told me to update the XDS firmware, since then it does not work anymore (it's not bricked, i can connect with the xds still firmware utility). Thats why I wanted to try remoteproc.

To use any example seems not to work, as I stated above, remoteproc fails for some of them and I don't know why.

Aside from that it noes not answer my two questions:

A: How to configure SYSBIOS tasks (XDC tools do not work in CCS). It would already help a little if you tell me if I am the only person where XDC tools do not work in CCS or if that is a bug or so in the 6.01.00 SDK.

B: A simple example which uses UART on the C7 DSP.

It would really satisfy me if you post a few lines of code which prints stuff to the UART on the C7x DSP.

Best regards

hi Jan,

Sorry for the trouble you are facing.

Attached is a sample code which does below, see also README.txt included in the tar file file.
It has a simple main.c with BIOS configured.
A timer is configured (appTimerInterruptInit).
A task is created (appMain) and printf is called every 10 OS ticks, (1 tick = 1ms).

This needs to be loaded and run from CCS.
The print goes to CCS console NOT UART.

This should help you get started with SysBIOS.

Note, we dont recommend to CCS projects and recommend to use makefile.

XDC/SysBIOS Config needs to be done via .cfg files. Lot of config can also be done via APIs in C code. Example see how a task in create in this sample code.

There is a "bios_common" folder where the SysBIOS config is done which is typically common across multiple CPUs (maybe overkill in this example but is helpful when there are more than one CPU in system running SysBIOS).

There is a "c7x_1.cfg" which has C7x specific core info.

I can help you with a similar app which can be loaded via linux boot loader, but I need some more info to  make such a sample app.

1. Do you want the C7x app to be loaded from a bootloader, i.e you dont want to use CCS ? Out recommendation is to use the Linux uboot as bootloader when not using CCS. This needs a "resource table" to be setup.

2. Linux itself uses one UART port, in our demos what we do is redirect a printf from SysBIOS side to a shared memory and then have a user space app on Linux to read from the shared memory and output to Linux console. This helps since when you have multiple CPUs you wont have enough UARTs to output prints from each CPU. Also its useful to see all prints from different CPUs in a common UART. Will this be ok for you rather than C7x controlling UART directly ? We highly recommend this approach.

3. Do you want Linux and C7x to be able to talk to each other ? Or you want C7x to be a standalone application just running in parallel to A72 Linux?

Based on this I can make simple app for you. The pieces of which are there in vision_apps.

Example,

1, needs a resource table to be setup (vision_apps/apps/basic_demos/app_tirtos/tirtos_linux/app_ipc_rsctable.h)

2. needs a utility API on C7x side and application on linux side (vision_apps/utils/console_io)

3. needs IPC to be init on C7x and Linux side (vision_apps/utils/ipc)

If you can tell me some of this info it will help me make a useful sample for you. Largely I will update the attach app to add these features.

regards
Kedar

https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/791/my_5F00_apps.tar.xz

Hi Kedar,

big thanks for the detailed answer and the example! This is a good start!

To your questions:

1) We basically don't want to use CCS. U-Boot would be OK but I would prefer a more dynamic way, like Linux remoteproc.
In development state this would enable us to compile C71/C66 firmware via makefile and directly load and test them.

2) This sounds exactly like what we need right now. I will check your information and try to use this.

3) Yes, we want to put parts of algorithms on the DSP. Note: We cannot use OpenCl since it is not ASIL conform.
We first want a simple IPC communication, like triggering tasks on the DSP from the A72, this should work with shared memory.
Later we may investigate OpenVx, but first we want basic IPC running.

Hope you can help me with this. It's very difficult for me to find the information I need. We have tons of documents which I studied but I rely on this forum mostly.

Best regards

Jan

I will update the app to include 1,2,3. I will need a day to give you a updated app. Note, we recommend to use uboot for loading. This is still remote proc, only it runs from uboot.

Regards

Kedar

Wow, thanks very much for the support.

I managed to modify the first version of your example to be loadable via Linux remoteproc.
I was very happy when I got this working. Now I try to integrate the printf and then I will close this thread when it works.

Thanks again! Your help was very good.

A question: I got the IPC remoteproc stuff working but is there a documentation for it other than the doxygen generated?

Best regards

Jan

Small update:

Your second example relies heavy on vision examples. So I try compiling them but get:

[GCC] Compiling C99 app_mem_linux_ion.c

/home/IBEO.AS/jahi/ti/psdk_rtos_auto_j7_06_01_00_15/vision_apps/utils/mem/src/app_mem_linux_ion.c:76:10: fatal error: ion/ion.h: No such file or directory

 #include <ion/ion.h>

"It looks like it does not find the Linux Kernel source. I tried to find out how the compiler is called but could not find a VERBOSE option in concerto.
So I have no idea how to fix this, I'm sure it's just a path thats not correct somewhere."

[KC] You don't need need Linux kernel but you need Linux target filesystem from PSDKLA (Processor SDK Linux Automotive).

See vision_apps/docs/user_guide/ENVIRONMENT_SETUP.html

See also vision_apps/docs/user_guide/BUILD_TROUBLE_SHOOTING.html

It tries to find ion.h file here ${PSDKRA_PATH}/targetfs/usr/include/ion/ion.h, check if you see this file here. And see if the Linux target filesystem exists at ${PSDKRA_PATH}/targetfs

To get verbose print pass SHOW_COMMANDS=1 to the make command as below

make SHOW_COMMANDS=1

"It would be much nicer to get the printf via shared memory working without using the vision apps. Thats a dependency I don't want to use."

[KC] We can do this, it will be a simple copy paste from vision_apps to here. There are few other utilities from here you will need including memory allocation, IPC. To get started hence I reused them. Let get this compiling and running and then I can help remove the vision_apps dependency. Note, you will still need the ion.h and some other files and .so's from Linux target filesystem to exchange shared buffers.

Btw, the ion.h is a memory allocator in Linux, this is needed for exchanging shared memory buffers between 2 CPUs. This is not need for print per se.

regards
Kedar

Sorry that I open this again.

I modified your app to load it via remoteproc (added resource table, modified linking) and it worked fine.

But when I added a construct like this:

volatile uint8_t* state = (uint8_t*)0xbc000100;

static Void appMain(UArg arg0, UArg arg1)
{
    *state = 1;
    while(1)
    {
        Task_sleep(10);
        *state = 2;
        printf("Hello, world !!!\n");
        *state = 3;
    }
}

I saw that it hangs at the Task_sleep() function. So I loaded the program via CCS + XDS and it worked fine.

I should mention that I read the state in Linux like this: sudo devmem2 0xbc000100

I assumed that there may be a problem with remoteproc and tried your unmodified example my_apps.tar.xz with the same state variable modification
and loaded this via U-Boot, but the memory address is never set.

I copied the binary to /lib/firmware/j7-c71_0-fw and in U-Boot I set dorprocboot=1.

So what am I doing wrong? I have no idea how to debug this.

Best regards Jan

Jan,

Can you confirm, there are two problems ?

1. "I saw that it hangs at the Task_sleep() function"

2. What you write in *state is not reflected on Linux side.

1. would be due to timer not setup, see my example, there will be a appTimerInterruptInit() in c7x_1/main.c, make sure your app calls this, else timer interrupt is not enabled and Task_sleep will never return

2. 0xbc000100 is cached on C7x side after a write you need to do a cache writeback using below BIOS API.

#include <ti/sysbios/hal/Cache.h>

   Cache_wb((Ptr)addr, (SizeT)size, (Bits16)Cache_Type_ALL, (Bool)TRUE);

Note also the invalidate and writeback invalidate API in BIOS below

Cache_wbInv((Ptr)addr, (SizeT)size, (Bits16)Cache_Type_ALL, (Bool)TRUE);

Cache_inv((Ptr)addr, (SizeT)size, (Bits16)Cache_Type_ALL, (Bool)TRUE);

On Linux side, when you do devmem2, this maps it as non-cached so once you do a writeback from C7x you should see it.

regards

Kedar