README.md

This is a placeholder for a PRU-based PocketBeagle tester.

Instructions

1. Grab https://rcn-ee.com/rootfs/bb.org/testing/2017-11-02/stretch-iot/bone-debian-9.2-iot-armhf-2017-11-02-4gb.img.xz
2. Program a microSD card with that image using http://etcher.io
3. Boot it on PocketBeagle
4. Clone this repo onto PocketBeagle
5. Run the following in the shell

make
echo none > /sys/class/leds/beaglebone\:green\:usr0/trigger
echo none > /sys/class/leds/beaglebone\:green\:usr1/trigger
echo none > /sys/class/leds/beaglebone\:green\:usr2/trigger
echo none > /sys/class/leds/beaglebone\:green\:usr3/trigger
sudo make run

Notes

• https://gist.github.com/jadonk/2ecf864e1b3f250bad82c0eae12b7b64
• sudo perl /opt/scripts/device/bone/show-pins.pl -v
• config-pin --help
• Bug tracker: http://bugs.elinux.org/projects/debian-image-releases
• http://elinux.org/EBC_Exercise_30_PRU_via_remoteproc_and_RPMsg
• http://elinux.org/EBC_Exercise_11b_gpio_via_mmap
• https://docs.google.com/presentation/d/1yMuyQwkYKU48LeMYnQj4sspnsbXf9niojWe_jr4BWjw/edit?usp=sharing
• http://processors.wiki.ti.com/images/3/34/Sitara_boot_camp_pru-module1-hw-overview.pdf
• http://processors.wiki.ti.com/index.php/PRU_Assembly_Instructions
• http://theduchy.ualr.edu/?p=996
• http://processors.wiki.ti.com/index.php/PRU_Projects

My procedure for cloning to PocketBeagle

Rather than put my PocketBeagle on the Internet, I execute the following on my host machine while my PocketBeagle is connected via USB:

git clone https://gist.github.com/8c3e697369b3207b57f042536cffe03f.git pocketbeagle-tester-pru
cd pocketbeagle-tester-pru
ssh debian@192.168.6.2 'bash -s' <<EOF
mkdir pocketbeagle-tester-pru
cd pocketbeagle-tester-pru
git init
git checkout -b dummy
EOF
git push debian@192.168.6.2:pocketbeagle-tester-pru/.git master

Version

Debian 9.x BeagleBoard.org BeagleBone IoT Image

sudo /opt/scripts/version.sh

AM335x_PRU.cmd

/****************************************************************************/
/*  AM335x_PRU.cmd                                                          */
/*  Copyright (c) 2015  Texas Instruments Incorporated                      */
/*                                                                          */
/*    Description: This file is a linker command file that can be used for  */
/*                 linking PRU programs built with the C compiler and       */
/*                 the resulting .out file on an AM335x device.             */
/****************************************************************************/

-cr								/* Link using C conventions */

/* Specify the System Memory Map */
MEMORY
{
      PAGE 0:
	PRU_IMEM		: org = 0x00000000 len = 0x00002000  /* 8kB PRU0 Instruction RAM */

      PAGE 1:

	/* RAM */

	PRU_DMEM_0_1	: org = 0x00000000 len = 0x00002000 CREGISTER=24 /* 8kB PRU Data RAM 0_1 */
	PRU_DMEM_1_0	: org = 0x00002000 len = 0x00002000	CREGISTER=25 /* 8kB PRU Data RAM 1_0 */

	  PAGE 2:
	PRU_SHAREDMEM	: org = 0x00010000 len = 0x00003000 CREGISTER=28 /* 12kB Shared RAM */

	DDR			    : org = 0x80000000 len = 0x00000100	CREGISTER=31
	L3OCMC			: org = 0x40000000 len = 0x00010000	CREGISTER=30


	/* Peripherals */

	PRU_CFG			: org = 0x00026000 len = 0x00000044	CREGISTER=4
	PRU_ECAP		: org = 0x00030000 len = 0x00000060	CREGISTER=3
	PRU_IEP			: org = 0x0002E000 len = 0x0000031C	CREGISTER=26
	PRU_INTC		: org = 0x00020000 len = 0x00001504	CREGISTER=0
	PRU_UART		: org = 0x00028000 len = 0x00000038	CREGISTER=7

	DCAN0			: org = 0x481CC000 len = 0x000001E8	CREGISTER=14
	DCAN1			: org = 0x481D0000 len = 0x000001E8	CREGISTER=15
	DMTIMER2		: org = 0x48040000 len = 0x0000005C	CREGISTER=1
	PWMSS0			: org = 0x48300000 len = 0x000002C4	CREGISTER=18
	PWMSS1			: org = 0x48302000 len = 0x000002C4	CREGISTER=19
	PWMSS2			: org = 0x48304000 len = 0x000002C4	CREGISTER=20
	GEMAC			: org = 0x4A100000 len = 0x0000128C	CREGISTER=9
	I2C1			: org = 0x4802A000 len = 0x000000D8	CREGISTER=2
	I2C2			: org = 0x4819C000 len = 0x000000D8	CREGISTER=17
	MBX0			: org = 0x480C8000 len = 0x00000140	CREGISTER=22
	MCASP0_DMA		: org = 0x46000000 len = 0x00000100	CREGISTER=8
	MCSPI0			: org = 0x48030000 len = 0x000001A4	CREGISTER=6
	MCSPI1			: org = 0x481A0000 len = 0x000001A4	CREGISTER=16
	MMCHS0			: org = 0x48060000 len = 0x00000300	CREGISTER=5
	SPINLOCK		: org = 0x480CA000 len = 0x00000880	CREGISTER=23
	TPCC			: org = 0x49000000 len = 0x00001098	CREGISTER=29
	UART1			: org = 0x48022000 len = 0x00000088	CREGISTER=11
	UART2			: org = 0x48024000 len = 0x00000088	CREGISTER=12

	RSVD10			: org = 0x48318000 len = 0x00000100	CREGISTER=10
	RSVD13			: org = 0x48310000 len = 0x00000100	CREGISTER=13
	RSVD21			: org = 0x00032400 len = 0x00000100	CREGISTER=21
	RSVD27			: org = 0x00032000 len = 0x00000100	CREGISTER=27

}

/* Specify the sections allocation into memory */
SECTIONS {
	/* Forces _c_int00 to the start of PRU IRAM. Not necessary when loading
	   an ELF file, but useful when loading a binary */
	.text:_c_int00*	>  0x0, PAGE 0

	.text		>  PRU_IMEM, PAGE 0
	.stack		>  PRU_DMEM_0_1, PAGE 1
	.bss		>  PRU_DMEM_0_1, PAGE 1
	.cio		>  PRU_DMEM_0_1, PAGE 1
	.data		>  PRU_DMEM_0_1, PAGE 1
	.switch		>  PRU_DMEM_0_1, PAGE 1
	.sysmem		>  PRU_DMEM_0_1, PAGE 1
	.cinit		>  PRU_DMEM_0_1, PAGE 1
	.rodata		>  PRU_DMEM_0_1, PAGE 1
	.rofardata	>  PRU_DMEM_0_1, PAGE 1
	.farbss		>  PRU_DMEM_0_1, PAGE 1
	.fardata	>  PRU_DMEM_0_1, PAGE 1

	.resource_table > PRU_DMEM_0_1, PAGE 1
}

Makefile

# 
# Copyright (c) 2016 Zubeen Tolani <ZeekHuge - zeekhuge@gmail.com>
# Copyright (c) 2017 Texas Instruments - Jason Kridner <jdk@ti.com>
#
PROJ_NAME=pb-tester-pru0

# PRU_CGT environment variable must point to the TI PRU compiler directory.
# PRU_SUPPORT points to pru-software-support-package
# Both are set in setup.sh
PRU_CGT:=/usr/share/ti/cgt-pru
PRU_SUPPORT:=/usr/lib/ti/pru-software-support-package

LINKER_COMMAND_FILE=./AM335x_PRU.cmd
LIBS=--library=$(PRU_SUPPORT)/lib/rpmsg_lib.lib
INCLUDE=--include_path=$(PRU_SUPPORT)/include --include_path=$(PRU_SUPPORT)/include/am335x
STACK_SIZE=0x100
HEAP_SIZE=0x100

CFLAGS=-v3 -O2 --display_error_number --endian=little --hardware_mac=on --obj_directory=$(GEN_DIR) --pp_directory=$(GEN_DIR) -ppd -ppa --asm_listing --c_src_interlist # --absolute_listing
LFLAGS=--reread_libs --warn_sections --stack_size=$(STACK_SIZE) --heap_size=$(HEAP_SIZE) -m $(GEN_DIR)/file.map

GEN_DIR=gen

PRU0_FW		=$(GEN_DIR)/$(PROJ_NAME).out

# -----------------------------------------------------
# Variable to edit in the makefile

# add the required firmwares to TARGETS
TARGETS		=$(PRU0_FW) $(GEN_DIR)/decay95.out

#------------------------------------------------------

.PHONY: all
all: $(TARGETS)
	@echo '-	Generated firmwares are : $^'

$(GEN_DIR)/decay95.out:  $(GEN_DIR)/decay95.obj
	@echo 'LD	$^' 
	@lnkpru -i$(PRU_CGT)/lib -i$(PRU_CGT)/include $(LFLAGS) -o $@ $^  $(LINKER_COMMAND_FILE) --library=libc.a $(LIBS) $^

$(GEN_DIR)/decay95.obj: $(PROJ_NAME).c 
	@mkdir -p $(GEN_DIR)
	@echo 'CC	$<'
	@clpru --define=DECAY_RATE=95 --include_path=$(PRU_CGT)/include $(INCLUDE) $(CFLAGS) -fe $@ $<

$(PRU0_FW): $(GEN_DIR)/$(PROJ_NAME).obj
	@echo 'LD	$^' 
	@lnkpru -i$(PRU_CGT)/lib -i$(PRU_CGT)/include $(LFLAGS) -o $@ $^  $(LINKER_COMMAND_FILE) --library=libc.a $(LIBS) $^

$(GEN_DIR)/$(PROJ_NAME).obj: $(PROJ_NAME).c 
	@mkdir -p $(GEN_DIR)
	@echo 'CC	$<'
	@clpru --include_path=$(PRU_CGT)/include $(INCLUDE) $(CFLAGS) -fe $@ $<

.PHONY: install run run95

install:
	@echo '-	copying firmware file $(PRU0_FW) to /lib/firmware/am335x-pru0-fw'
	@cp $(PRU0_FW) /lib/firmware/am335x-pru0-fw

run: install
	@echo '-	rebooting pru core 0'
	$(shell echo "4a334000.pru0" > /sys/bus/platform/drivers/pru-rproc/unbind 2> /dev/null)
	$(shell echo "4a334000.pru0" > /sys/bus/platform/drivers/pru-rproc/bind)
	@echo "-	pru core 0 is now loaded with $(PRU0_FW)"

run95:
	@echo '-	copying firmware file $(GEN_DIR)/decay95.out to /lib/firmware/am335x-pru0-fw'
	@cp $(GEN_DIR)/decay95.out /lib/firmware/am335x-pru0-fw
	@echo '-	rebooting pru core 0'
	$(shell echo "4a334000.pru0" > /sys/bus/platform/drivers/pru-rproc/unbind 2> /dev/null)
	$(shell echo "4a334000.pru0" > /sys/bus/platform/drivers/pru-rproc/bind)
	@echo "-	pru core 0 is now loaded with $(GEN_DIR)/decay95.out"

.PHONY: clean
clean:
	@echo 'CLEAN	.'
	@rm -rf $(GEN_DIR) $(PROJ_NAME).asm

pb-tester-pru0.c

/*
 * Source Modified by Zubeen Tolani < ZeekHuge - zeekhuge@gmail.com >
 * Based on the examples distributed by TI
 *
 * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/
 *
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *	* Redistributions of source code must retain the above copyright
 *	  notice, this list of conditions and the following disclaimer.
 *
 *	* Redistributions in binary form must reproduce the above copyright
 *	  notice, this list of conditions and the following disclaimer in the
 *	  documentation and/or other materials provided with the
 *	  distribution.
 *
 *	* Neither the name of Texas Instruments Incorporated nor the names of
 *	  its contributors may be used to endorse or promote products derived
 *	  from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
				  
#include <stdint.h>
#include <pru_cfg.h>
#include <pru_ctrl.h>
#include "resource_table_empty.h"

#define	INS_PER_US 200           // 5ns per instruction
#define INS_PER_DELAY_LOOP 2	 // two instructions per delay loop
#define DELAY_CYCLES_US (INS_PER_US / INS_PER_DELAY_LOOP)

#define GPIO1 0x4804C000
#define GPIO_CLEARDATAOUT 0x190
#define GPIO_SETDATAOUT 0x194
#define USR0 (1<<21)
#define USR1 (1<<22)
#define USR2 (1<<23)
#define USR3 (1<<24)
unsigned int volatile * const GPIO1_CLEAR = (unsigned int *) (GPIO1 + GPIO_CLEARDATAOUT);
unsigned int volatile * const GPIO1_SET = (unsigned int *) (GPIO1 + GPIO_SETDATAOUT);

volatile register unsigned int __R30;
volatile register unsigned int __R31;
#define PRU0_GPIO (1<<2)

#ifndef DECAY_RATE
#define DECAY_RATE 100
#endif
#ifndef DELAY_CYCLES
#define DELAY_CYCLES DELAY_CYCLES_US
#endif

const int decay = DECAY_RATE;

void main(void) {
	int i, j;

	/* Clear SYSCFG[STANDBY_INIT] to enable OCP master port */
	CT_CFG.SYSCFG_bit.STANDBY_INIT = 0;

	for(i = 1000000; i > 0; i = (i * decay) / 100) {
#ifndef LED_DISABLE
		*GPIO1_SET = USR0;
#endif
#ifndef GPIO_DISABLE
		__R30 |= PRU0_GPIO;
#endif
		for(j=0;j<i;j++){ __delay_cycles(DELAY_CYCLES); }
#ifndef LED_DISABLE
		*GPIO1_CLEAR = USR0;
#endif
#ifndef GPIO_DISABLE
		__R30 ^= PRU0_GPIO;
#endif
		for(j=0;j<i;j++){ __delay_cycles(DELAY_CYCLES); }
	}

	__halt();
}

resource_table_empty.h

/*
 * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/
 *
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *	* Redistributions of source code must retain the above copyright
 *	  notice, this list of conditions and the following disclaimer.
 *
 *	* Redistributions in binary form must reproduce the above copyright
 *	  notice, this list of conditions and the following disclaimer in the
 *	  documentation and/or other materials provided with the
 *	  distribution.
 *
 *	* Neither the name of Texas Instruments Incorporated nor the names of
 *	  its contributors may be used to endorse or promote products derived
 *	  from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 *  ======== resource_table_empty.h ========
 *
 *  Define the resource table entries for all PRU cores. This will be
 *  incorporated into corresponding base images, and used by the remoteproc
 *  on the host-side to allocated/reserve resources.  Note the remoteproc
 *  driver requires that all PRU firmware be built with a resource table.
 *
 *  This file contains an empty resource table.  It can be used either as:
 *
 *        1) A template, or
 *        2) As-is if a PRU application does not need to configure PRU_INTC
 *                  or interact with the rpmsg driver
 *
 */

#ifndef _RSC_TABLE_PRU_H_
#define _RSC_TABLE_PRU_H_

#include <stddef.h>
#include <rsc_types.h>

struct my_resource_table {
	struct resource_table base;

	uint32_t offset[1]; /* Should match 'num' in actual definition */
};

#pragma DATA_SECTION(pru_remoteproc_ResourceTable, ".resource_table")
#pragma RETAIN(pru_remoteproc_ResourceTable)
struct my_resource_table pru_remoteproc_ResourceTable = {
	1,	/* we're the first version that implements this */
	0,	/* number of entries in the table */
	0, 0,	/* reserved, must be zero */
	0,	/* offset[0] */
};

#endif /* _RSC_TABLE_PRU_H_ */