7. PRU-ICSS Firmware¶

7.1. Dual EMAC and Switch¶

Introduction

DUAL_EMAC

ICSS DUAL EMAC FIRMWARE is a single port Ethernet MAC (Media Access Control) i.e. Layer 2 of OSI Model. It implements a 2 port ethernet mac supporting 10/100 Mbps. DUAL EMAC FIRMWARE is standardized to IEEE 802.1 Ethernet Standards. Primary use case of the protocol is to demonstrate basic ethernet functionality via both PRU cores on 10/100 Mbit Ethernet cable. ICSS DUAL EMAC FIRMWARE can be used independently on two PRU’s to implement two independent MAC’s with two different MAC addresses and two different IP addresses. To provide an analogy, this is somewhat similar to a two port Ethernet PCIe NIC card on a PC.Ethernet interface in this case is available along with Host processor on a single SoC. Following are high level features:

SWITCH

ICSS SWITCH FIRMWARE is a three port learning Ethernet switch i.e. Layer 2 of OSI Model. It implements a 2 port cut through ethernet switch supporting at 100 Mbps. SWITCH FIRMWARE is standardized to IEEE 802.1 Ethernet Standards. The primary use case of the protocol is to use Ethernet to automate applications which require short cut-through latency and low hardware costs. ICSS SWITCH FIRMWARE uses two PRU to implement three port Ethernet switch with one single MAC and IP address. To provide an analogy, this is somewhat standard network switch only here the network functionality is available to the host core within the single SOC. The following are the high level features it supports.

Code Organization

Firmware Build Instruction

Build instruction from Processor SDK Release package

Pre-requisites to Building

Refer to the Processor SDK RTOS Building page for information on setting up build environment.

Compiling ICSS-EMAC FIRMWARES

• cd <PDK>/packages/ti/drv/icss_emac
• make firm

Firmware binaries at the end of the build will be located at:

• <PDK>/packages/ti/drv/icss_emac/firmware/<FIRMWARE_TYPE>/bin/<SOC>/<HOST_CORE>/<REVISION>
• <FIRMWARE_TYPE> indicates the firmware type i.e. icss_dualemac for DUAL_EMAC or icss_switch for SWITCH
• <SOC> indicates the SOC type.
• <HOST_CORE> indicates the Host core type on which the built binary can be loaded.
• <REVISION> indicates the revision of the firmware binary based on core. (There are 2 revision of PRU ICSS core)

Build instruction from GIT

Following are the steps for building firmware from any external environment outside PROC SDK RTOS.

• Creation of directories
  • Create a working directory e.g. <WORK_DIR>
  • Create a new directory named ti inside working directory. i.e. <WORK_DIR/ti>
  • Create a new directory called drv inside ti. i.e. <WORK_DIR/ti/drv>
• Clone of Repos
  • Git clone pdk build repo into ti directory. i.e. <WORK_DIR/ti/build>
  • Git clone icss_emac repo into ti/drv directory. i.e. <WORK_DIR/ti/drv/icss_emac>
• Setting Environment Variables
  • Export CLPRU install path. i.e. export CL_PRU_INSTALL_PATH=clpru toolchain directory
  • Export pdk install path. i.e. export PDK_INSTALL_PATH=<WORK_DIR>
  • Export LIMIT_SOCS Variable i.e. LIMIT_SOCS=<SOC> [Optional for limiting to some SOCs]
• Build command
  • Run make firm/firm_clean to build/clean firmware from icss_emac directory i.e. <WORK_DIR/ti/drv/icss_emac>
• Generated binaries
  • the firmware binaries which will be located in <WORK_DIR/ti/drv/icss_emac/firmware/<FIRMWARE_TYPE>/bin/<SOC>/<HOST_CORE>/<REVISION>>

Supported EVMs

The following is a list of EVMS supported and the PRU-ICSS ethernet ports to be used:

Running ICSS-EMAC FIRMWARES Example

Please go through the following page for example demonstrating the use of the firmware via icss-emac driver. [1]

Firmware Design Guide

NOTE: For normal use case, there is no need to refer this document. Unless you wish to go through the internal working for firmware and/or wanted to modify it.

7.2. PRU-ICSS SORTE¶

Introduction

Protocol Overview

The SORTE protocol is a TI-developed industrial Ethernet protocol that supports 4-µs cycle time. The SORTE protocol operates on the PRU-ICSS, which is an industrial peripheral within Sitara and KeyStone processors from Texas Instruments. SORTE protocol operates exclusively on the PRU-ICSS; therefore, the ARM Cortex-A8, A9 or A15 processors – depending on the device family – are available for industrial applications. The SORTE protocol differentiate between two network components: the master and one or more slave devices. For in depth details of the protocol please refer to the the design documents as listed in the References section below.

Code Organization

THE SORTE ARM application and firmware sources can be found under the following directory :

<PDK>/packages/ti/drv/pruss/example/apps/sorte/

Refer to the README.txt in this directory for details of directory layout.

In addition, there is a README.txt which provides high-level over of how the protocol is implmented for master and slave device network compoments which can be found at:

<PDK>/packages/ti/drv/pruss/example/apps/sorte/firmware/src/master/README.txt

<PDK>/packages/ti/drv/pruss/example/apps/sorte/firmware/src/slave/README.txt

Building the Examples

Pre-requisites to Building

1. Set your environment using pdksetupenv.sh. Building the Firmware binaries and ARM application uses the same environment variables as the pruss driver library build. Refer to the Processor SDK RTOS Building page for information on setting up your build environment.

Compiling the PRUSS SORTE Firmware

To build the SORTE firmware binaries:

1. cd <PDK>/packages/ti/drv/pruss
2. make firm

This will make the firmware binaries which will be located in:

<PDK>/packages/ti/drv/pruss/example/apps/sorte/firmware/bin/<BOARD>

Compiling the PRUSS SORTE Application

To build the SORTE ARM applications:

1. cd <PDK>/packages/ti/drv/pruss
2. make apps

This will make the ARM applications for both master and slave device which will be located in:

<PDK>/packages/ti/drv/pruss/example/apps/sorte/slave<BOARD>

<PDK>/packages/ti/drv/pruss/example/apps/sorte/master<BOARD>

Supported EVMs

The following is a list of EVMS supported and the PRU-ICSS ethernet ports to be used:

Running the PRUSS SORTE Example

In order to run the SORTE applications, you will require 1 EVM running as master and 2 EVMs running as slave(slave1/slave2). Use CCS to load and run the master and slave applications respectively.

Prior to running the applications its best to connect the EVMS as follows:

Connect master Port0 to slave1 Port0. Connect slave1 Port1 to slave2 Port0.

Note that the master device will wait until it discovers 2 slave devices in the network. UART console on the master will print the following until 2 slave devices are detected:

sorte master: waiting for atleast 2 SLAVE devices connected

Once 2 slave devices are detected by the master, the following print will be seen on UART console and master will continue with state machine and protocol processing:

sorte master: 2 SLAVE devices connected

The slave device via the UART console will continuosly display the number of packets its received during input output exchange state of the protocol until pass criteria is reached as follows(as an example):

sorte slave: test in progress: current receive packet count: 35000

sorte slave: test in progress: current receive packet count: 40000

Once pass criteria number of packets have been received, the following print will be displayed on UART console:

All tests have passed

Additional Reference

7.3. PRU-ICSS I2C¶

Introduction

FIRMWARE FEATURES

PRU-ICSS-I2C firmware supports standard two pin I2C interface through three GPIO pins from PRU-ICSS peripheral. I2C SCL pin for firmware is implemented with single GPIO configured in GPI mode. While I2C SDA pin is implemented with two GPIO pins, one pin configured in GPI mode for taking input sample and second pin configured in GPO mode for driving the line. Depending on Baud rate, firmware can emulate multiple instance of I2C interface from a single PRU core. Following are high level features:

Code Organization

Firmware Build Instruction

Build instruction from Processor SDK Release package

Pre-requisites to Building

Refer to the Processor SDK RTOS Building page for information on setting up build environment.

Compiling I2C FIRMWARE

• cd <PDK>/packages/ti/drv/i2c
• make firm

Firmware binaries at the end of the build will be located at:

• <PDK>/packages/ti/drv/i2c/firmware/<FIRMWARE_TYPE>/bin/<SOC>/<HOST_CORE>/<REVISION>
• <FIRMWARE_TYPE> indicates the firmware type i.e. icss_i2c
• <SOC> indicates the SOC type.
• <HOST_CORE> indicates the Host core type on which the built binary can be loaded.
• <REVISION> indicates the revision of the firmware binary based on core. (There are 2 revision of PRU-ICSS core)

Build instruction for GIT

Following are the steps for building firmware from any external environment outside Processor SDK RTOS package.

• Creation of directories
  • Create a working directory e.g. <WORK_DIR>
  • Create a new directory named ti inside working directory. i.e. <WORK_DIR/ti>
  • Create a new directory called drv inside ti. i.e. <WORK_DIR/ti/drv>
• Clone of Repos
  • Git clone pdk build repo into ti directory. i.e. <WORK_DIR/ti/build>
  • Git clone i2c repo into ti/drv directory. i.e. <WORK_DIR/ti/drv/i2c>
• Setting Environment Variables
  • Export CLPRU install path. i.e. export CL_PRU_INSTALL_PATH=clpru toolchain directory
  • Export pdk install path. i.e. export PDK_INSTALL_PATH=<WORK_DIR>
  • Export LIMIT_SOCS Variable i.e. LIMIT_SOCS=<SOC> [Optional for limiting to some SOCs]
• Build command
  • Run make firm_clean/firm to clean/build firmware from i2c directory i.e. <WORK_DIR/ti/drv/i2c>
• Generated binaries
  • the firmware binaries which will be located in <WORK_DIR/ti/drv/i2c/firmware/<FIRMWARE_TYPE>/bin/<SOC>/<HOST_CORE>/<REVISION>>

Supported EVMs

Following are list supported EVMs along with the pin configurations:

icev2AM335x

idkAM572x/idkAM574x

idkAM437x

I2C FIRMWARE Example

 Sample code for initiating I2C FW transaction:

...
Board_init(boardCfg);
...
/* Initialize the I2C fw configuration */
I2C_socInitFwCfg();

/* Get the default I2C init configurations */
I2C_socGetFwCfg(I2C_TEST_INSTANCE1, &i2c_cfg);

/* Modify the default I2C configurations if necessary */

/* Set the default I2C init configurations */
I2C_socSetFwCfg(I2C_TEST_INSTANCE1, &i2c_cfg);

I2C_init();

i2c = I2C_open(peripheralNum, &i2cParams);
...
...

/* Initiate I2C transfers. Refer Example for details
*/
I2C_transactionInit(&i2cTransaction);
transaction.masterMode   = true;
...
...
transferOK = I2C_transfer(i2c, &i2cTransaction);
if (transferOK != I2C_STS_SUCCESS) {
/* I2C transaction failed */
}

 For SMBUS  transaction:

...
testCmd.transferCmd = SMBUS_WRITE_BYTE_CMD;
testCmd.cmdCode = WRITE_SMBUS_COMMAND_CODE;
controlStatus = I2C_control(handle, I2C_CMD_SMBUS_TYPE, ((void*)&testCmd));
I2C_transactionInit(&i2cTransaction);
...
transferOK = I2C_transfer(i2c, &i2cTransaction);
if (transferOK != I2C_STS_SUCCESS) {
/* I2C transaction failed */
}

Examples List

Firmware Design Guide

NOTE: For normal use case, there is no need to refer this document. Unless you wish to go through the internal working for firmware and/or wanted to modify it.