On Thu, Jul 18, 2019 at 8:24 AM Vijay Kumar Banerjee <vijaykumar9...@gmail.com> wrote: > > --- > user/bsps/arm/beagle.rst | 91 +++++++++++++++++++++++++++++++++++++++- > 1 file changed, 89 insertions(+), 2 deletions(-) > > diff --git a/user/bsps/arm/beagle.rst b/user/bsps/arm/beagle.rst > index a36efde..84bfe2d 100644 > --- a/user/bsps/arm/beagle.rst > +++ b/user/bsps/arm/beagle.rst > @@ -1,8 +1,95 @@ > .. SPDX-License-Identifier: CC-BY-SA-4.0 > > -.. Copyright (C) 2019 TBD > +.. Copyright (C) 2019 Vijay Kumar Banerjee > > beagle > ====== > > -TODO. > +This BSP supports four variants, `beagleboardorig`, `beagleboardxm`, > `beaglebonewhite`
We need a style guide for writing docs. I will send in separate email though I wondered if we should set a maximum line length/line breaks at 80 char as with code? > +and `beagleboneblack`. The basic hardware initialization is not performed by > +the BSP. A boot loader with device tree support must be used to start the > BSP, > +e.g. U-Boot. There is always a comma after e.g. > + > +TODO(These drivers are present but not documented yet): > + > + * Clock driver. > + * Network Interface Driver. > + * SDcard driver. > + * GPIO Driver. > + * Console driver. > + * PWM Driver. > + * RTC driver. > + > +Boot via U-Boot > +--------------- > +To boot via uboot, the ELF must be converted to a U-Boot image like below: > + > +.. code-block:: none > + > + arm-rtems5-objcopy hello.exe -O app.bin > + gzip 9 app.bin > + mkimage -A arm -O linux -T kernel -a 0x80000000 -e 0x80000000 -n RTEMS > -d app.bin.gz rtems-app.img > + > +Getting the Device Tree Blob > +---------------------------- > + > +The Device Tree Blob(dtb) is needed to load the device tree while starting up We (American, British) normally put a space before parentheticals such as defining an acronym, like "Blob (dtb)". > +the kernel. We build the dtb from the FreeBSD source matching the commit hash > +from the libbsd HEAD of freebsd-org. For example if the HEAD is at > +"19a6ceb89dbacf74697d493e48c388767126d418" > +Then the right dts file is: dts should be mentioned before this > +https://github.com/freebsd/freebsd/blob/19a6ceb89dbacf74697d493e48c388767126d418/sys/gnu/dts/arm/am335x-boneblack.dts > + > +.. code-block:: none > + > + #building the dtb > + #We will use the script from > https://github.com/freebsd/freebsd/blob/19a6ceb89dbacf74697d493e48c388767126d418/sys/tools/fdt/make_dtb.sh > + > + export MACHINE='arm' #The make_dtb.sh script uses environment variable > MACHINE > + SCRIPT_DIR=$HOME/freebsd/sys/tools/fdt > + #The arguments to the script are > + # $1 -> Build Tree > + # $2 -> DTS source file > + # $3 -> output path of the DTB file > + ${SCRIPT_DIR}/make_dtb.sh ${SCRIPT_DIR}/../../ \ > + ${SCRIPT_DIR}/../../gnu/dts/arm/am335x-boneblack.dts \ > + $(pwd) > +Writing the uEnv.txt file > +------------------------- > + > +The uEnv.txt file is needed to set any environment variable before the > kernel is > +loaded. Each line is a u-boot command that the uboot will execute during > +starting up. "during starting" is awkward, try "during start up" or "while starting up" > + > +Add the following to a file named uEnv.txt: > + > +.. code-block:: none > + > + setenv bootdelay 5 > + uenvcmd=run boot > + boot=fatload mmc 0 0x80800000 rtems-app.img ; fatload mmc 0 0x88000000 > am335x-boneblack.dtb ; bootm 0x80800000 - 0x88000000 > + > +I2C Driver > +---------- > + > +This BSP uses the I2C framework and is registered using > +``am335x_i2c_bus_register()`` the function prototype is given below: > + > +.. code-block:: C > + > + int am335x_i2c_bus_register( > + const char *bus_path, > + uintptr_t register_base, > + uint32_t input_clock, > + rtems_vector_number irq > + ); > + > +This function is needed only while registering with custom path with custom This "registering with custom path" is awkward, maybe it needs "registering with a custom path" > +values. For registering the `/dev/i2c-0` device, a wrapper function is > provided, > +``bbb_register_i2c_0()`` similarly ``bbb_register_i2c_1()`` and > +``bbb_register_i2c_2()`` are respectively used to register `i2c-1` and > `i2c-2`. > + > +SPI Driver > +---------- > + > +The SPI device `/dev/spi-0` can be registered with ``bbb_register_spi_0()``` > -- Thanks for contributing documentation! > 2.20.1 > > _______________________________________________ > devel mailing list > devel@rtems.org > http://lists.rtems.org/mailman/listinfo/devel _______________________________________________ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
