[PATCH 1/3] doc: ti: Convert am335x_evm README to rST
Tom Rini
trini at konsulko.com
Sat Sep 11 14:57:31 CEST 2021
Convert the existing documentation to rST, keeping to just making
formatting changes to start with.
Signed-off-by: Tom Rini <trini at konsulko.com>
---
.../README => doc/board/ti/am335x_evm.rst | 150 ++++++++++--------
doc/board/ti/index.rst | 1 +
2 files changed, 87 insertions(+), 64 deletions(-)
rename board/ti/am335x/README => doc/board/ti/am335x_evm.rst (67%)
diff --git a/board/ti/am335x/README b/doc/board/ti/am335x_evm.rst
similarity index 67%
rename from board/ti/am335x/README
rename to doc/board/ti/am335x_evm.rst
index 19e0eccbac93..51c11a3e51f8 100644
--- a/board/ti/am335x/README
+++ b/doc/board/ti/am335x_evm.rst
@@ -1,3 +1,6 @@
+.. SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+.. sectionauthor:: Tom Rini <trini at konsulko.com>
+
Summary
=======
@@ -5,17 +8,17 @@ This document covers various features of the 'am335x_evm' build, and some of
the related build targets (am335x_evm_uartN, etc).
Hardware
-========
+--------
The binary produced by this board supports, based on parsing of the EEPROM
documented in TI's reference designs:
-- AM335x GP EVM
-- AM335x EVM SK
-- Beaglebone White
-- Beaglebone Black
+* AM335x GP EVM
+* AM335x EVM SK
+* Beaglebone White
+* Beaglebone Black
Customization
-=============
+-------------
Given that all of the above boards are reference platforms (and the
Beaglebone platforms are OSHA), it is likely that this platform code and
@@ -24,12 +27,12 @@ worth noting that aside from things such as NAND or MMC only being
required if a custom platform makes use of these blocks, the following
are required, depending on design:
-- GPIO is only required if DDR3 power is controlled in a way similar to
- EVM SK
-- SPI is only required for SPI flash, or exposing the SPI bus.
+* GPIO is only required if DDR3 power is controlled in a way similar to EVM SK
+* SPI is only required for SPI flash, or exposing the SPI bus.
The following blocks are required:
-- I2C, to talk with the PMIC and ensure that we do not run afoul of
+
+* I2C, to talk with the PMIC and ensure that we do not run afoul of
errata 1.0.24.
When removing options as part of customization,
@@ -41,7 +44,7 @@ the IP blocks, so both areas will need their choices updated to reflect
the custom design.
NAND
-====
+----
The AM335x GP EVM ships with a 256MiB NAND available in most profiles. In
this example to program the NAND we assume that an SD card has been
@@ -58,6 +61,9 @@ Step-1: Building u-boot for NAND boot
CONFIG_NAND_OMAP_ECCSCHEME (refer doc/README.nand)
Step-2: Flashing NAND via MMC/SD
+
+.. code-block:: text
+
# select BOOTSEL to MMC/SD boot and boot from MMC/SD card
U-Boot # mmc rescan
# erase flash
@@ -84,7 +90,7 @@ Step-3: Set BOOTSEL pin to select NAND boot, and POR the device.
The device should boot from images flashed on NAND device.
NOR
-===
+---
The Beaglebone White can be equipped with a "memory cape" that in turn can
have a NOR module plugged into it. In this case it is then possible to
@@ -100,14 +106,16 @@ prepended. In the following example we use a size of 512KiB (0x80000)
as that is how much space we set aside before the environment, as per
the config file.
-U-Boot # mmc rescan
-U-Boot # load mmc 0 ${loadaddr} u-boot.bin
-U-Boot # protect off 08000000 +80000
-U-Boot # erase 08000000 +80000
-U-Boot # cp.b ${loadaddr} 08000000 ${filesize}
+.. code-block:: text
+
+ U-Boot # mmc rescan
+ U-Boot # load mmc 0 ${loadaddr} u-boot.bin
+ U-Boot # protect off 08000000 +80000
+ U-Boot # erase 08000000 +80000
+ U-Boot # cp.b ${loadaddr} 08000000 ${filesize}
Falcon Mode
-===========
+-----------
The default build includes "Falcon Mode" (see doc/README.falcon) via NAND,
eMMC (or raw SD cards) and FAT SD cards. Our default behavior currently is
@@ -119,18 +127,20 @@ boards with multiple boot methods, recovery should not be an issue in this
worst-case however.
Falcon Mode: eMMC
-=================
+-----------------
The recommended layout in this case is:
-MMC BLOCKS |--------------------------------| LOCATION IN BYTES
-0x0000 - 0x007F : MBR or GPT table : 0x000000 - 0x020000
-0x0080 - 0x00FF : ARGS or FDT file : 0x010000 - 0x020000
-0x0100 - 0x01FF : SPL.backup1 (first copy used) : 0x020000 - 0x040000
-0x0200 - 0x02FF : SPL.backup2 (second copy used) : 0x040000 - 0x060000
-0x0300 - 0x06FF : U-Boot : 0x060000 - 0x0e0000
-0x0700 - 0x08FF : U-Boot Env + Redundant : 0x0e0000 - 0x120000
-0x0900 - 0x28FF : Kernel : 0x120000 - 0x520000
+.. code-block:: text
+
+ MMC BLOCKS |--------------------------------| LOCATION IN BYTES
+ 0x0000 - 0x007F : MBR or GPT table : 0x000000 - 0x020000
+ 0x0080 - 0x00FF : ARGS or FDT file : 0x010000 - 0x020000
+ 0x0100 - 0x01FF : SPL.backup1 (first copy used) : 0x020000 - 0x040000
+ 0x0200 - 0x02FF : SPL.backup2 (second copy used) : 0x040000 - 0x060000
+ 0x0300 - 0x06FF : U-Boot : 0x060000 - 0x0e0000
+ 0x0700 - 0x08FF : U-Boot Env + Redundant : 0x0e0000 - 0x120000
+ 0x0900 - 0x28FF : Kernel : 0x120000 - 0x520000
Note that when we run 'spl export' it will prepare to boot the kernel.
This includes relocation of the uImage from where we loaded it to the entry
@@ -144,28 +154,30 @@ had a FAT partition (such as on a Beaglebone Black) it is not enough to
write garbage into the area, you must delete it from the partition table
first.
-# Ensure we are able to talk with this mmc device
-U-Boot # mmc rescan
-U-Boot # tftp 81000000 am335x/MLO
-# Write to two of the backup locations ROM uses
-U-Boot # mmc write 81000000 100 100
-U-Boot # mmc write 81000000 200 100
-# Write U-Boot to the location set in the config
-U-Boot # tftp 81000000 am335x/u-boot.img
-U-Boot # mmc write 81000000 300 400
-# Load kernel and device tree into memory, perform export
-U-Boot # tftp 81000000 am335x/uImage
-U-Boot # run findfdt
-U-Boot # tftp ${fdtaddr} am335x/${fdtfile}
-U-Boot # run mmcargs
-U-Boot # spl export fdt 81000000 - ${fdtaddr}
-# Write the updated device tree to MMC
-U-Boot # mmc write ${fdtaddr} 80 80
-# Write the uImage to MMC
-U-Boot # mmc write 81000000 900 2000
+.. code-block:: text
+
+ # Ensure we are able to talk with this mmc device
+ U-Boot # mmc rescan
+ U-Boot # tftp 81000000 am335x/MLO
+ # Write to two of the backup locations ROM uses
+ U-Boot # mmc write 81000000 100 100
+ U-Boot # mmc write 81000000 200 100
+ # Write U-Boot to the location set in the config
+ U-Boot # tftp 81000000 am335x/u-boot.img
+ U-Boot # mmc write 81000000 300 400
+ # Load kernel and device tree into memory, perform export
+ U-Boot # tftp 81000000 am335x/uImage
+ U-Boot # run findfdt
+ U-Boot # tftp ${fdtaddr} am335x/${fdtfile}
+ U-Boot # run mmcargs
+ U-Boot # spl export fdt 81000000 - ${fdtaddr}
+ # Write the updated device tree to MMC
+ U-Boot # mmc write ${fdtaddr} 80 80
+ # Write the uImage to MMC
+ U-Boot # mmc write 81000000 900 2000
Falcon Mode: FAT SD cards
-=========================
+-------------------------
In this case the additional file is written to the filesystem. In this
example we assume that the uImage and device tree to be used are already on
@@ -173,23 +185,31 @@ the FAT filesystem (only the uImage MUST be for this to function
afterwards) along with a Falcon Mode aware MLO and the FAT partition has
already been created and marked bootable:
-U-Boot # mmc rescan
-# Load kernel and device tree into memory, perform export
-U-Boot # load mmc 0:1 ${loadaddr} uImage
-U-Boot # run findfdt
-U-Boot # load mmc 0:1 ${fdtaddr} ${fdtfile}
-U-Boot # run mmcargs
-U-Boot # spl export fdt ${loadaddr} - ${fdtaddr}
+.. code-block:: text
+
+ U-Boot # mmc rescan
+ # Load kernel and device tree into memory, perform export
+ U-Boot # load mmc 0:1 ${loadaddr} uImage
+ U-Boot # run findfdt
+ U-Boot # load mmc 0:1 ${fdtaddr} ${fdtfile}
+ U-Boot # run mmcargs
+ U-Boot # spl export fdt ${loadaddr} - ${fdtaddr}
This will print a number of lines and then end with something like:
- Using Device Tree in place at 80f80000, end 80f85928
- Using Device Tree in place at 80f80000, end 80f88928
+
+.. code-block:: text
+
+ Using Device Tree in place at 80f80000, end 80f85928
+ Using Device Tree in place at 80f80000, end 80f88928
+
So then you:
-U-Boot # fatwrite mmc 0:1 0x80f80000 args 8928
+.. code-block:: text
+
+ U-Boot # fatwrite mmc 0:1 0x80f80000 args 8928
Falcon Mode: NAND
-=================
+-----------------
In this case the additional data is written to another partition of the
NAND. In this example we assume that the uImage and device tree to be are
@@ -197,9 +217,11 @@ already located on the NAND somewhere (such as filesystem or mtd partition)
along with a Falcon Mode aware MLO written to the correct locations for
booting and mtdparts have been configured correctly for the board:
-U-Boot # nand read ${loadaddr} kernel
-U-Boot # load nand rootfs ${fdtaddr} /boot/am335x-evm.dtb
-U-Boot # run nandargs
-U-Boot # spl export fdt ${loadaddr} - ${fdtaddr}
-U-Boot # nand erase.part u-boot-spl-os
-U-Boot # nand write ${fdtaddr} u-boot-spl-os
+.. code-block:: text
+
+ U-Boot # nand read ${loadaddr} kernel
+ U-Boot # load nand rootfs ${fdtaddr} /boot/am335x-evm.dtb
+ U-Boot # run nandargs
+ U-Boot # spl export fdt ${loadaddr} - ${fdtaddr}
+ U-Boot # nand erase.part u-boot-spl-os
+ U-Boot # nand write ${fdtaddr} u-boot-spl-os
diff --git a/doc/board/ti/index.rst b/doc/board/ti/index.rst
index c0da04b109cb..014a097178ab 100644
--- a/doc/board/ti/index.rst
+++ b/doc/board/ti/index.rst
@@ -6,4 +6,5 @@ Texas Instruments
.. toctree::
:maxdepth: 2
+ am335x_evm
j721e_evm
--
2.17.1
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