From: Peter Hoyes Peter.Hoyes@arm.com
Create a new documentation section for Arm Ltd boards with a sub-page for the vexpress board (FVP-A, FVP-R and Juno).
Document how the armv8_switch_to_el1 environment variable can be used to switch between booting from S-EL2/S-EL1 at runtime on the BASER_FVP.
Signed-off-by: Peter Hoyes Peter.Hoyes@arm.com --- doc/arch/arm64.rst | 3 +- doc/board/armltd/index.rst | 9 ++++++ doc/board/armltd/vexpress64.rst | 57 +++++++++++++++++++++++++++++++++ doc/board/index.rst | 1 + 4 files changed, 69 insertions(+), 1 deletion(-) create mode 100644 doc/board/armltd/index.rst create mode 100644 doc/board/armltd/vexpress64.rst
diff --git a/doc/arch/arm64.rst b/doc/arch/arm64.rst index 80498f6f6b..f20eb8f1b2 100644 --- a/doc/arch/arm64.rst +++ b/doc/arch/arm64.rst @@ -18,7 +18,8 @@ Notes classical firmware (like initial hardware setup, CPU errata workarounds or SMP bringup). U-Boot can be entered in EL2 when its main purpose is that of a boot loader. It can drop to lower exception levels before - entering the OS. + entering the OS. For ARMv8-R it is recommened to enter at S-EL2, as for this + architecture there is no S-EL3.
2. U-Boot for arm64 is compiled with AArch64-gcc. AArch64-gcc use rela relocation format, a tool(tools/relocate-rela) by Scott Wood diff --git a/doc/board/armltd/index.rst b/doc/board/armltd/index.rst new file mode 100644 index 0000000000..b6786c114f --- /dev/null +++ b/doc/board/armltd/index.rst @@ -0,0 +1,9 @@ +.. SPDX-License-Identifier: GPL-2.0+ + +Arm Ltd +============= + +.. toctree:: + :maxdepth: 2 + + vexpress64.rst diff --git a/doc/board/armltd/vexpress64.rst b/doc/board/armltd/vexpress64.rst new file mode 100644 index 0000000000..23cf6aec88 --- /dev/null +++ b/doc/board/armltd/vexpress64.rst @@ -0,0 +1,57 @@ +.. SPDX-License-Identifier: GPL-2.0+ + +Arm Versatile Express +===================== + +The vexpress_* board configuration supports the following platforms: + + * FVP_Base_RevC-2xAEMvA + * FVP_BaseR_AEMv8R + * Juno development board + +Fixed Virtual Platforms +----------------------- + +The Fixed Virtual Platforms (FVP) are complete simulations of an Arm system, +including processor, memory and peripherals. They are set out in a "programmer's +view", which gives a comprehensive model on which to build and test software. + +The supported FVPs are available free of charge and can be downloaded from the +Arm developer site [1]_ (user registration might be required). + +Supported features: + + * GICv3 + * Generic timer + * PL011 UART + * SMC91111 network interface + +The default configuration assumes that U-Boot is boostrapped from the start of +the DRAM (address 0x80000000 for AEMvA; 0x00000000 for AEMv8R) using a suitable +bootloader. Alternatively, U-Boot can be launched directly by mapping the binary +to the same address (using the FVP's --data argument). + +The FVPs can be debugged using Arm Development Studio [2]_. + +FVP_BaseR +^^^^^^^^^ + +On Armv8r64 platforms (such as the FVP_BaseR), U-Boot runs at S-EL2, so +CONFIG_ARMV8_SWITCH_TO_EL1 is defined so that the next stage boots at S-EL1. If +S-EL2 is desired instead, the *armv8_switch_to_el1* environment variable is +available. This can be set to *n* to override the config flag and boot the next +stage at S-EL2 instead. + +Juno +---- + +The Juno development board is an open, vendor-neutral Armv8-A development +platform that supports an out-of-the-box Linux software package. A range of +plug-in expansion options enables hardware and software applications to be +developped and debugged. + +References +---------- + +.. [1] https://developer.arm.com/tools-and-software/simulation-models/fixed-virtual... +.. [2] https://developer.arm.com/tools-and-software/embedded/arm-development-studio diff --git a/doc/board/index.rst b/doc/board/index.rst index 9e90978891..cd4f273b4d 100644 --- a/doc/board/index.rst +++ b/doc/board/index.rst @@ -10,6 +10,7 @@ Board-specific doc advantech/index AndesTech/index amlogic/index + armltd/index atmel/index congatec/index coreboot/index