Cyclone V HPS UART, can't rx data

One more question.

I build preloader (SPL) from u-boot sources (https://github.com/altera-opensource/u-boot-socfpga, socfpga_v2013.01.01) with handsoff defaults from repository:

make mrproper

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- socfpga_cyclone5_config

make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf-

I get u-boot.img and u-boot-spl.bin. The last one I use to build preloader-mkpimage.bin:

mkpimage --header-version 0 -o preloader-mkpimage.bin u-boot-spl.bin u-boot-spl.bin u-boot-spl.bin u-boot-s pl.bin

But after updating SD card's partition 2 with this .bin (dd if=preloader-mkpimage.bin of=/dev/mmcblk0p3 bs=64k seek=0) - board doesn't boot at all.

And now I am wondering if there is anything which I should modify (at prloader/u-boot sources) before building u-boot-spl.bin.

u-boot build with the same way (u-boot.img) works fine.

I've tried to build preloader-mkpimage.bin according to the https://rocketboards.org/foswiki/view/documentation/avgsrdpreloader as well but results are the same - board doesn't boot at all - no single character on serial console.

Thanks

Hi,

I am trying to establish an UART communication between two cyclone V SoCs. I am using the FPGA option enabled in Qsys for UART in both SoCs. I have got the communication running between them, for eg. I can send a string using 'echo hello SoC > /dev/ttyS1' and my application running on other SoC receives the string. Now I am running an application at Tx side, where I want to send a string(for test purposes, later on will be a data of around 20 bytes) cyclically,(running Angstrom with a RT patch). However, at the Rx side, I receive the string only once, and then the 'read' function call blocks. At the Tx side, the further transmission fails with an error 'Invalid Argument', basically for the 'write' function. However, the first write succeeds.

Here is a snippet :

// Init code, common for both SoCs.

if ((file_des_uart = open("/dev/ttyS1", O_RDWR | O_NOCTTY )) < 0) {
		  perror("Failed to open the UART device file: ");
		exit(1);
	}
	else {
		puts ("uart ok");
	}
        struct termios options;
	tcgetattr(file_des_uart, &options);
	options.c_cflag = B115200 | CS8 | CLOCAL | CREAD;		//<Set baud rate
	options.c_iflag = IGNPAR;
	options.c_oflag = 0;
	options.c_lflag = 0;
	tcflush(file_des_uart, TCIFLUSH);
	tcsetattr(file_des_uart, TCSANOW, &options);

//At Tx side

 char* tx_buf = "Hello SoC";
               while(1 && cntr < 5) {
		bytesSent = write(file_des_uart,(tx_buf),(strlen(tx_buf)+1));
		if(bytesSent != strlen(tx_buf)+1) {
			perror("Error: ");
			break;
		}
		cntr++; //break after sending 5 times

// At Rx side

  while(1)
	{
		if ((bytesSent = read(file_des_uart,(void*)rx_buf,50)) > 0) {
			printf("uart : Received msg = %s\n",rx_buf);
		}
		if(bytesSent < 0) {
			perror("uart : error in reading uart : ");
			//break;
		}
               if(bytesSent == 0 {
                       printf("No data");
               }                       
         }

As far as I know, I am not using the DMA option, since I have not configured it anywhere, and I prefer not to use it. I would like to have a simple UART communication, between the two SoCs.

Does anyone have a hand on this issue?