Whitebox
/
u-boot
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
upstream u-boot with additional patches for our devices/boards: https://lists.denx.de/pipermail/u-boot/2017-March/282789.html (AXP crashes) ; Gbit ethernet patch for some LIME2 revisions ; with SPI flash support
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
52200 Commits
3 Branches
0 Tags
148 MiB
Tag: Branch: Tree: abb205ded1
Branches Tags
${ item.name }
Create tag ${ searchTerm }
Create branch ${ searchTerm }
from 'abb205ded1'
${ noResults }
u-boot/doc/README.semihosting

39 lines
1.7 KiB
Raw Normal View History Unescape

SPDX: Convert all of our single license tags to Linux Kernel style When U-Boot started using SPDX tags we were among the early adopters and there weren't a lot of other examples to borrow from. So we picked the area of the file that usually had a full license text and replaced it with an appropriate SPDX-License-Identifier: entry. Since then, the Linux Kernel has adopted SPDX tags and they place it as the very first line in a file (except where shebangs are used, then it's second line) and with slightly different comment styles than us. In part due to community overlap, in part due to better tag visibility and in part for other minor reasons, switch over to that style. This commit changes all instances where we have a single declared license in the tag as both the before and after are identical in tag contents. There's also a few places where I found we did not have a tag and have introduced one. Signed-off-by: Tom Rini <trini@konsulko.com>
7 years ago
SPDX-License-Identifier: GPL-2.0+
arm: Add support for semihosting for armv8 fastmodel targets. The armv8 ARM Trusted Firmware (ATF) can be used to load various ATF images and u-boot, and does this for virtual platforms by using semihosting. This commit extends this idea by allowing u-boot to also use semihosting to load the kernel/ramdisk/dtb. This eliminates the need for a bootwrapper and produces a more realistic boot sequence with virtual models. Though the semihosting code is quite generic, support for armv7 in fastmodel is less useful due to the wide range of available silicon and the lack of a free armv7 fastmodel, so this change contains an untested armv7 placeholder for the service trap opcode. Please refer to doc/README.semihosting for a more detailed description of semihosting and how it is used with the armv8 virtual platforms. Signed-off-by: Darwin Rambo <drambo@broadcom.com> Cc: trini@ti.com Cc: fenghua@phytium.com.cn Cc: bhupesh.sharma@freescale.com
11 years ago
/*
* Copyright 2014 Broadcom Corporation.
*/
Semihosting is ARM's way of having a real or virtual target communicate
with a host or host debugger for basic operations such as file I/O,
console I/O, etc. Please see
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0471c/Bgbjjgij.html for more information.
For developing on armv8 virtual fastmodel platforms, semihosting is a
valuable tool since it allows access to image/configuration files before
eMMC or other NV media are available.
There are two main ARM virtual Fixed Virtual Platform (FVP) models,
Versatile Express (VE) FVP and BASE FVP (See
http://www.arm.com/products/tools/models/fast-models/foundation-model.php)
The initial vexpress64 u-boot board created here runs on the VE virtual
platform using the license-free Foundation_v8 simulator. Fortunately,
the Foundation_v8 simulator also supports the BASE_FVP model which
companies can purchase licenses for and contain much more functionality.
So we can, in u-boot, run either model by either using the VE FVP (default),
or turning on CONFIG_BASE_FVP for the more full featured model.
Rather than create a new armv8 board similar to armltd/vexpress64, add
semihosting calls to the existing one, enabled with CONFIG_SEMIHOSTING
and CONFIG_BASE_FVP both set. Also reuse the existing board config file
vexpress_aemv8a.h but differentiate the two models by the presence or
absence of CONFIG_BASE_FVP. This change is tested and works on both the
Foundation and Base fastmodel simulators.
armv8: semihosting: add a command to load semihosted images Instead of sprinkling custom code and calls over the Vexpress64 boardfile, create a command that loads images using semihosting just like we would load from flash memory of over the network, using a special command: smhload <image> <address> This will make it possible to remove some custom calls and code and make the boot easier. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
10 years ago
The semihosting code adds a command:
arm: Add support for semihosting for armv8 fastmodel targets. The armv8 ARM Trusted Firmware (ATF) can be used to load various ATF images and u-boot, and does this for virtual platforms by using semihosting. This commit extends this idea by allowing u-boot to also use semihosting to load the kernel/ramdisk/dtb. This eliminates the need for a bootwrapper and produces a more realistic boot sequence with virtual models. Though the semihosting code is quite generic, support for armv7 in fastmodel is less useful due to the wide range of available silicon and the lack of a free armv7 fastmodel, so this change contains an untested armv7 placeholder for the service trap opcode. Please refer to doc/README.semihosting for a more detailed description of semihosting and how it is used with the armv8 virtual platforms. Signed-off-by: Darwin Rambo <drambo@broadcom.com> Cc: trini@ti.com Cc: fenghua@phytium.com.cn Cc: bhupesh.sharma@freescale.com
11 years ago
armv8: semihosting: add a command to load semihosted images Instead of sprinkling custom code and calls over the Vexpress64 boardfile, create a command that loads images using semihosting just like we would load from flash memory of over the network, using a special command: smhload <image> <address> This will make it possible to remove some custom calls and code and make the boot easier. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
10 years ago
smhload <image> <address> [env var]
arm: Add support for semihosting for armv8 fastmodel targets. The armv8 ARM Trusted Firmware (ATF) can be used to load various ATF images and u-boot, and does this for virtual platforms by using semihosting. This commit extends this idea by allowing u-boot to also use semihosting to load the kernel/ramdisk/dtb. This eliminates the need for a bootwrapper and produces a more realistic boot sequence with virtual models. Though the semihosting code is quite generic, support for armv7 in fastmodel is less useful due to the wide range of available silicon and the lack of a free armv7 fastmodel, so this change contains an untested armv7 placeholder for the service trap opcode. Please refer to doc/README.semihosting for a more detailed description of semihosting and how it is used with the armv8 virtual platforms. Signed-off-by: Darwin Rambo <drambo@broadcom.com> Cc: trini@ti.com Cc: fenghua@phytium.com.cn Cc: bhupesh.sharma@freescale.com
11 years ago
armv8: semihosting: add a command to load semihosted images Instead of sprinkling custom code and calls over the Vexpress64 boardfile, create a command that loads images using semihosting just like we would load from flash memory of over the network, using a special command: smhload <image> <address> This will make it possible to remove some custom calls and code and make the boot easier. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
10 years ago
That will load an image from the host filesystem into RAM at the specified
address and optionally store the load end address in the specified
environment variable.