Convert the documentation for the Broadcom BCM7445 and BCM7260 boards to reStructuredText format and add the new filename to doc/board/broadcom/index.rst. ---
Changes in v2: - Remove "About this" heading
doc/README.bcm7xxx | 156 ---------------------------- doc/board/broadcom/bcm7xxx.rst | 183 +++++++++++++++++++++++++++++++++ doc/board/broadcom/index.rst | 1 + 3 files changed, 184 insertions(+), 156 deletions(-) delete mode 100644 doc/README.bcm7xxx create mode 100644 doc/board/broadcom/bcm7xxx.rst
diff --git a/doc/README.bcm7xxx b/doc/README.bcm7xxx deleted file mode 100644 index 6839da5f97..0000000000 --- a/doc/README.bcm7xxx +++ /dev/null @@ -1,156 +0,0 @@ -Summary -======= - -This document describes how to use U-Boot on the Broadcom 7445 SoC, as -a third stage bootloader loaded by Broadcom's BOLT bootloader. - -BOLT loads U-Boot as a generic ELF binary. Some U-Boot features such -as networking are not yet available but other important features are, -including: - - - ext4 file system traversal - - - support for loading FIT images - - - advanced scripting - - - support for FIT-provided DTBs instead of relying on the - BOLT-provided DTB - -A customized version of this port has been used in production. The -same approach may work on other BCM7xxx boards, with some -configuration adjustments and memory layout experimentation. - -Build -===== - -make bcm7445_defconfig -make -${CROSS_COMPILE}strip u-boot - -Run -=== - -To tell U-Boot which serial port to use for its console, set the -"stdout-path" property in the "/chosen" node of the BOLT-generated -device tree. For example: - -BOLT> dt add prop chosen stdout-path s serial0:115200n8 - -Flash the u-boot binary into board storage, then invoke it from BOLT. -For example: - -BOLT> boot -bsu -elf flash0.u-boot1 - -This port assumes that I-cache and D-cache are already enabled when -U-Boot is entered. - -Flattened Image Tree Support -============================ - -What follows is an example FIT image source file. Build it with: - -mkimage -f image.its image.itb - -Booting the resulting image.itb was tested on BOLT v1.20, with the -following kernels: - -https://github.com/Broadcom/stblinux-3.14 -https://github.com/Broadcom/stblinux-4.1 -https://github.com/Broadcom/stblinux-4.9 - -and with a generic ARMv7 root file system. - -image.its: -/dts-v1/; -/ { - description = "BCM7445 FIT"; - images { - kernel@1 { - description = "Linux kernel"; - /* - * This kernel image output format can be - * generated with: - * - * make vmlinux - * ${CROSS_COMPILE}objcopy -O binary -S vmlinux vmlinux.bin - * gzip -9 vmlinux.bin - * - * For stblinux-3.14, the specific Broadcom - * board type should be configured in the - * kernel, for example CONFIG_BCM7445D0=y. - */ - data = /incbin/("<vmlinux.bin.gz>"); - type = "kernel"; - arch = "arm"; - os = "linux"; - compression = "gzip"; - load = <0x8000>; - entry = <0x8000>; - hash@1 { - algo = "sha256"; - }; - }; - ramdisk@1 { - description = "Initramfs root file system"; - data = /incbin/("<initramfs.cpio.gz>"); - type = "ramdisk"; - arch = "arm"; - os = "linux"; - compression = "gzip"; - /* - * Set the environment variable initrd_high to - * 0xffffffff, and set "load" and "entry" here - * to 0x0 to keep initramfs in-place and to - * accommodate stblinux bmem/CMA reservations. - */ - load = <0x0>; - entry = <0x0>; - hash@1 { - algo = "sha256"; - }; - }; - fdt@1 { - description = "Device tree dumped from BOLT"; - /* - * This DTB should be similar to the - * BOLT-generated device tree, after BOLT has - * done its runtime modifications to it. For - * example, it can be dumped from within - * U-Boot (at ${fdtcontroladdr}), after BOLT - * has loaded U-Boot. The result can be added - * to the Linux source tree as a .dts file. - * - * To support modifications to the device tree - * in-place in U-Boot, add to Linux's - * arch/arm/boot/dts/Makefile: - * - * DTC_FLAGS ?= -p 4096 - * - * This will leave some padding in the DTB and - * thus reserve room for node additions. - * - * Also, set the environment variable fdt_high - * to 0xffffffff to keep the DTB in-place and - * to accommodate stblinux bmem/CMA - * reservations. - */ - data = /incbin/("<bolt-<version>.dtb"); - type = "flat_dt"; - arch = "arm"; - compression = "none"; - hash@1 { - algo = "sha256"; - }; - }; - }; - configurations { - default = "conf@bcm7445"; - conf@bcm7445 { - description = "BCM7445 configuration"; - kernel = "kernel@1"; - ramdisk = "ramdisk@1"; - fdt = "fdt@1"; - }; - }; -}; diff --git a/doc/board/broadcom/bcm7xxx.rst b/doc/board/broadcom/bcm7xxx.rst new file mode 100644 index 0000000000..f1994d9f97 --- /dev/null +++ b/doc/board/broadcom/bcm7xxx.rst @@ -0,0 +1,183 @@ +.. SPDX-License-Identifier: GPL-2.0+ +.. Copyright (C) 2018, 2023 Thomas Fitzsimmons fitzsim@fitzsim.org + +BCM7445 and BCM7260 +=================== + +This document describes how to use U-Boot on the Broadcom 7445 and +Broadcom 7260 SoC, as a third stage bootloader loaded by Broadcom's +BOLT bootloader. + +BOLT loads U-Boot as a generic ELF binary. Some U-Boot features such +as networking are not implemented but other important features are, +including: + +* ext4 file system traversal +* support for loading FIT images +* advanced scripting +* support for FIT-provided DTBs instead of relying on the BOLT-provided DTB + +A customized version of this port has been used in production. The +same approach may work on other BCM7xxx boards, with some +configuration adjustments and memory layout experimentation. + +Configure +--------- + +BCM7445 +^^^^^^^ + +.. code-block:: console + + $ make bcm7445_defconfig + +BCM7260 +^^^^^^^ + +.. code-block:: console + + $ make bcm7260_defconfig + +Build +----- + +.. code-block:: console + + $ make + $ ${CROSS_COMPILE}strip u-boot + +Run +--- + +To tell U-Boot which serial port to use for its console, set the +``stdout-path`` property in the ``/chosen`` node of the BOLT-generated +device tree. For example: + +:: + + BOLT> dt add prop chosen stdout-path s serial0:115200n8 + +Flash the ``u-boot`` binary into board storage, then invoke it from +BOLT. For example: + +:: + + BOLT> boot -bsu -elf flash0.u-boot1 + +This port assumes that I-cache and D-cache are already enabled when +U-Boot is entered. + +Flattened Image Tree Support +---------------------------- + +What follows is an example FIT image source file. Build it with: + +.. code-block:: console + + $ mkimage -f image.its image.itb + +Booting the resulting ``image.itb`` was tested on BOLT v1.20, with the +following kernels: + +* https://github.com/Broadcom/stblinux-3.14 +* https://github.com/Broadcom/stblinux-4.1 +* https://github.com/Broadcom/stblinux-4.9 + +and with a generic ARMv7 root file system. + +**image.its** + +:: + + /dts-v1/; + / { + description = "BCM7445 FIT"; + images { + kernel@1 { + description = "Linux kernel"; + /* + * This kernel image output format can be + * generated with: + * + * make vmlinux + * ${CROSS_COMPILE}objcopy -O binary -S vmlinux vmlinux.bin + * gzip -9 vmlinux.bin + * + * For stblinux-3.14, the specific Broadcom + * board type should be configured in the + * kernel, for example CONFIG_BCM7445D0=y. + */ + data = /incbin/("<vmlinux.bin.gz>"); + type = "kernel"; + arch = "arm"; + os = "linux"; + compression = "gzip"; + load = <0x8000>; + entry = <0x8000>; + hash@1 { + algo = "sha256"; + }; + }; + ramdisk@1 { + description = "Initramfs root file system"; + data = /incbin/("<initramfs.cpio.gz>"); + type = "ramdisk"; + arch = "arm"; + os = "linux"; + compression = "gzip"; + /* + * Set the environment variable initrd_high to + * 0xffffffff, and set "load" and "entry" here + * to 0x0 to keep initramfs in-place and to + * accommodate stblinux bmem/CMA reservations. + */ + load = <0x0>; + entry = <0x0>; + hash@1 { + algo = "sha256"; + }; + }; + fdt@1 { + description = "Device tree dumped from BOLT"; + /* + * This DTB should be similar to the + * BOLT-generated device tree, after BOLT has + * done its runtime modifications to it. For + * example, it can be dumped from within + * U-Boot (at ${fdtcontroladdr}), after BOLT + * has loaded U-Boot. The result can be added + * to the Linux source tree as a .dts file. + * + * To support modifications to the device tree + * in-place in U-Boot, add to Linux's + * arch/arm/boot/dts/Makefile: + * + * DTC_FLAGS ?= -p 4096 + * + * This will leave some padding in the DTB and + * thus reserve room for node additions. + * + * Also, set the environment variable fdt_high + * to 0xffffffff to keep the DTB in-place and + * to accommodate stblinux bmem/CMA + * reservations. + */ + data = /incbin/("<bolt-<version>.dtb"); + type = "flat_dt"; + arch = "arm"; + compression = "none"; + hash@1 { + algo = "sha256"; + }; + }; + }; + configurations { + default = "conf@bcm7445"; + conf@bcm7445 { + description = "BCM7445 configuration"; + kernel = "kernel@1"; + ramdisk = "ramdisk@1"; + fdt = "fdt@1"; + }; + }; + }; diff --git a/doc/board/broadcom/index.rst b/doc/board/broadcom/index.rst index 4f0e825fef..a56bd1f069 100644 --- a/doc/board/broadcom/index.rst +++ b/doc/board/broadcom/index.rst @@ -7,4 +7,5 @@ Broadcom .. toctree:: :maxdepth: 2
+ bcm7xxx raspberrypi