Commit graph

9 commits

Author SHA1 Message Date
Vadzim Dambrouski
7bdf75ca5c arm: fix compile warnings when semihosting is enabled on ARMv7M target.
This patch fixes compile warnings like this:

warning: format '%lu' expects argument of type 'long unsigned int',
         but argument 5 has type 'size_t'

In C99 standard you can use %zu modifier to print size_t values.

Signed-off-by: Vadzim Dambrouski <pftbest@gmail.com>
2015-11-10 09:45:36 +01:00
Vadzim Dambrouski
432a6241bd arm: add support for semihosting for ARMv7M targets
If you enable CONFIG_SEMIHOSTING for STM32F429 target, you will get compile
error looking like this:

arch/arm/lib/semihosting.c: In function 'smh_read':
{standard input}: Assembler messages:
{standard input}:34: Error: invalid swi expression
{standard input}:34: Error: value of 1193046 too large for field of 2 bytes at 0
scripts/Makefile.build:277: recipe for target 'arch/arm/lib/semihosting.o' failed

The source of the problem is "svc #0x123456" instruction. This instruction
can not be encoded using Thumb2 instruction set used by ARMv7M CPUs.
ARM documentation suggests using "bkpt #0xAB" instruction instead [1].
This patch fixes compile errors and adds support for semihosting for
STM32F429 or any other ARMv7M target.
This change was sested on STM32F429-DISCOVERY board using OpenOCD and
"smhload" u-boot command.

[1] http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0471c/Bgbjhiea.html

Signed-off-by: Vadzim Dambrouski <pftbest@gmail.com>
2015-11-10 09:45:33 +01:00
Linus Walleij
d5f3d17ca6 armv8: semihosting: delete external interface
Now that loading files using semihosting can be done using
a command in standard scripts, and we have rewritten the boardfile
and added it to the Vexpress64, let's delete the external
interface to the semihosting file retrieveal and rely solely
on these commands, and staticize them inside that file so the
whole business is self-contained.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-28 12:07:46 -04:00
Linus Walleij
202a674bb8 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>
2015-03-28 12:07:45 -04:00
Linus Walleij
e769f68613 armv8: semihosting: do not inline trap call
The semihosting trap call does not like being inlined, probably
because that will mean register reordering screwing up the return
value in r0, so tag this function "noinline".

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-28 12:07:45 -04:00
Linus Walleij
9be5c661be arm: semihosting: get rid of forward declarations
By rearranging the functions in the semihosting code we can
avoid forward-declaration of the internal static functions.
This puts the stuff in a logical order: read/open/close/len
and then higher-order functions follow at the end.

Cc: Darwin Rambo <drambo@broadcom.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Mark Hambleton <mark.hambleton@arm.com>
Cc: Tom Rini <trini@ti.com>
Acked-by: Steve Rae <srae@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-12-29 07:44:06 -05:00
Linus Walleij
4e1ef15091 arm: semihosting: fix up compile bugs
There is currently a regression when using newer ARM64 compilers
for semihosting: the way long types are inferred from context
is no longer the same.

The semihosting runtime uses long and size_t, so use this
explicitly in the semihosting code and interface, and voila:
the code now works again.

Tested with aarch64-linux-gnu-gcc: Linaro GCC 4.9-2014.09.

Cc: Darwin Rambo <drambo@broadcom.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Mark Hambleton <mark.hambleton@arm.com>
Cc: Tom Rini <trini@ti.com>
Acked-by: Steve Rae <srae@broadcom.com>
Suggested-by: Mark Hambleton <mark.hambleton@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-12-29 07:44:06 -05:00
Linus Walleij
50b5639430 arm: semihosting: staticize internal functions
The semihosting code exposes internal file handle handling
functions to read(), open(), close() and get the length of
a certain file handle.

However the code using it is only interested in either
reading and entire named file into memory or getting the
file length of a file referred by name. No file handles
are used.

Thus make the file handle code internal to this file by
removing these functions from the semihosting header file
and staticize them.

This gives us some freedom to rearrange the semihosting
code without affecting the external interface.

Cc: Darwin Rambo <drambo@broadcom.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Mark Hambleton <mark.hambleton@arm.com>
Cc: Tom Rini <trini@ti.com>
Acked-by: Steve Rae <srae@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-12-29 07:44:06 -05:00
Darwin Rambo
261d27605c 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
2014-07-03 08:35:45 +02:00