Commit graph

86 commits

Author SHA1 Message Date
York Sun
2a1680e30e common/board_f: Initialized global data for generic board
Some platforms (tested on mpc85xx, mpc86xx) use global data before calling
function baord_inti_f(). The data should not be cleared later. Any arch
which uses global data in generic board board_init_f() should define
CONFIG_SYS_GENERIC_GLOBAL_DATA.

Signed-off-by: York Sun <yorksun@freescale.com>
CC: Scott Wood <scottwood@freescale.com>
CC: Simon Glass <sjg@chromium.org>
CC: Albert ARIBAUD <albert.u.boot@aribaud.net>
Acked-by: Simon Glass <sjg@chromium.org>
2014-05-12 15:20:05 -04:00
Masahiro Yamada
097c5de5f4 sandbox: ignore sandbox.dtb
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
2014-05-09 14:51:20 -06:00
Masahiro Yamada
258060905e sandbox: move source files from board/ to arch/sandbox/
Prior to commit 33a02da0, all boards must have board/${BOARD}/
or board/${VENDOR}/${BOARD}/ directory.
Now this rule is obsolete.

It looks weird that sandbox defines "vendor" and "board" just for
meeting the old U-Boot directory structure.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Simon Glass <sjg@chromium.org>
2014-05-09 14:51:14 -06:00
Simon Glass
ad0e463954 sandbox: Provide a build option to avoid using SDL
Some machines do not have SDL libraries installed, and it is still useful
to build sandbox without LCD/keyboard support.

Add an option for this, used as follows:

    make sandbox_config all NO_SDL=1

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-05-09 14:47:13 -06:00
Simon Glass
ab839dc3e6 sandbox: Add options to clean up temporary files
When jumping from one sandbox U-Boot to another in sandbox, the RAM buffer
is preserved in the jump by using a temporary file. Add an option to tell
the receiving U-Boot to remove this file when it is no longer needed.

Similarly the old U-Boot image is left behind in this case. We cannot delete
it immediately since gdb cannot then find its debug symbols. Delete it just
before exiting.

Together these changes ensure that temporary files are removed both for
memory and U-Boot.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-17 20:05:49 -06:00
Simon Glass
ffb87905cb sandbox: Allow Ctrl-C to work in sandbox
It is useful for Cltl-C to be handled by U-Boot as it is on other boards.
But it is also useful to be able to terminate U-Boot with Ctrl-C.

Add an option to enable signals while in raw mode, and make this the
default. Add an option to leave the terminal cooked, which is useful for
redirecting output.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-17 20:05:49 -06:00
Simon Glass
7d95f2a329 sandbox: Add LCD driver
Add a simple LCD driver which uses SDL to display the image. We update the
image regularly, while still providing for reasonable performance.

Adjust the common lcd code to support sandbox.

For command-line runs we do not want the LCD to be displayed, so add a
--show_lcd option to enable it.

Tested-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-17 20:05:49 -06:00
Simon Glass
c34c0246a3 sandbox: Add a simple sound driver
Add a sound driver for sandbox, which uses SDL.

Tested-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-17 20:05:48 -06:00
Simon Glass
bbc09bf27e sandbox: Add SDL library for LCD, keyboard, audio
SDL (Simple DirectMedia Layer - see www.libsdl.org) is a library which
provides simple graphics and sound features. It works under X11 and also
with a simple frame buffer interface. It is ideally suited to sandbox
U-Boot since it fits nicely with the low-level feature set required by
U-Boot. For example, U-Boot has its own font drawing routines, its own
keyboard processing and just needs raw sound output.

We can use SDL to provide emulation of these basic functions for sandbox.
This significantly expands the testing that is possible with sandbox.

Add a basic SDL library which we will use in future commits.

Tested-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-17 20:05:48 -06:00
Simon Glass
bda7773f04 sandbox: Add -j option to indicate a jump from a previous U-Boot
In order to support the 'go' command we allow the jumping U-Boot to pass its
filename to the new U-Boot image. This can then be used to delete that image
if required.

Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Che-Liang Chiou <clchiou@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-17 20:05:48 -06:00
Simon Glass
47f5fcfb41 sandbox: Add os_jump_to_image() to run another executable
For some tests it is useful to be able to run U-Boot again but pass on the
same memory contents. Add a function to achieve this.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-17 20:05:48 -06:00
Simon Glass
39741c01e6 sandbox: dts: Add display and keyboard to sandbox
Add an LCD display and keyboard to the sandbox device tree so that these
features can be used.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-17 20:05:45 -06:00
Simon Glass
66bd1cff90 Use a const pointer for map_to_sysmem()
This function does not actually change the pointer contents, so use const
so that functions which have a const pointer do not need to cast.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-17 20:05:45 -06:00
Stephen Warren
cfd13e8dda unit-test: make "test -e" test independent of $CWD
The unit-test for hush's "test -e" currently relies upon being run in
the U-Boot build directory, because it tests for the existence of a file
that exists in that directory.

Fix this by explicitly creating the file we use for the existence test,
and deleting it afterwards so that multiple successive unit-test
invocations succeed. This required adding an os.c function to erase
files.

Reported-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
2014-03-07 10:59:06 -05:00
Simon Glass
e2d8a714a7 sandbox: Convert GPIOs to use driver model
Convert sandbox over to use driver model GPIOs.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-04 12:15:30 -05:00
Simon Glass
714a5621c2 sandbox: Build a device tree file for sandbox
Add support for building a device tree for sandbox's CONFIG_OF_HOSTFILE
option to make it easier to use device tree with sandbox.

This adjusts the Makefile to build a u-boot.dtb file which can be passed
to sandbox U-Boot with:

   ./u-boot -d u-boot.dtb

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-04 12:15:28 -05:00
Masahiro Yamada
ad0fed46b9 kbuild: use shorten log for linking u-boot
Move sandbox-specific link rule to arch/sandbox/config.mk.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
2014-02-25 11:01:29 -05:00
Masahiro Yamada
6825a95b0b kbuild: use Linux Kernel build scripts
Now we are ready to switch over to real Kbuild.

This commit disables temporary scripts:
  scripts/{Makefile.build.tmp, Makefile.host.tmp}
and enables real Kbuild scripts:
  scripts/{Makefile.build,Makefile.host,Makefile.lib}.

This switch is triggered by the line in scripts/Kbuild.include
  -build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build.tmp obj
  +build := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.build obj

We need to adjust some build scripts for U-Boot.
But smaller amount of modification is preferable.

Additionally, we need to fix compiler flags which are
locally added or removed.

In Kbuild, it is not allowed to change CFLAGS locally.
Instead, ccflags-y, asflags-y, cppflags-y,
CFLAGS_$(basetarget).o, CFLAGS_REMOVE_$(basetarget).o
are prepared for that purpose.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Tested-by: Gerhard Sittig <gsi@denx.de>
2014-02-19 11:07:50 -05:00
Masahiro Yamada
9e4140329e kbuild: change out-of-tree build
This commit changes the working directory
where the build process occurs.

Before this commit, build process occurred under the source
tree for both in-tree and out-of-tree build.

That's why we needed to add $(obj) prefix to all generated
files in makefiles like follows:
  $(obj)u-boot.bin:  $(obj)u-boot

Here, $(obj) is empty for in-tree build, whereas it points
to the output directory for out-of-tree build.

And our old build system changes the current working directory
with "make -C <sub-dir>" syntax when descending into the
sub-directories.

On the other hand, Kbuild uses a different idea
to handle out-of-tree build and directory descending.

The build process of Kbuild always occurs under the output tree.
When "O=dir/to/store/output/files" is given, the build system
changes the current working directory to that directory and
restarts the make.

Kbuild uses "make -f $(srctree)/scripts/Makefile.build obj=<sub-dir>"
syntax for descending into sub-directories.
(We can write it like "make $(obj)=<sub-dir>" with a shorthand.)
This means the current working directory is always the top
of the output directory.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Tested-by: Gerhard Sittig <gsi@denx.de>
2014-02-19 11:07:50 -05:00
Masahiro Yamada
3d83efbce9 sandbox: Use system headers first for sandbox's os.c in a different way
Commit cbe5cdfcd changed config.mk and arch/sandbox/cpu/Makefile
to use -idirafter instead of -I and remove -nostdinc.

But
 * Sandbox-specific code dirties config.mk
 * os.c is compiled without such compiler flags as:
      -Wall -Wstrict-prototypes -Wno-format-security
      -fno-builtin -ffreestanding -fno-stack-protector
      -fstack-usage -Wno-format-nonliteral

This commit use -idirafter and remove the -nostdinc
differently and more simply.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Simon Glass <sjg@chromium.org>
2014-01-29 16:08:52 -05:00
Masahiro Yamada
347d06dec4 sandbox: fix the return type of os_free() function
The function os_free() returns nothing.
Its return type should be "void" rather than "void *".

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
2014-01-24 16:59:08 -05:00
Simon Glass
b88eb329ce sandbox: Add a prototype for cleanup_before_linux()
This function is defined but has no prototype declaration. Add it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-01-08 17:26:01 -07:00
Simon Glass
1209e2727c sandbox: Add facility to save/restore sandbox state
It is often useful to be able to save out the state from a sandbox test
run, for analysis or to restore it later to continue a test. Add generic
infrastructure for doing this using a device tree binary file. This is
a flexible tagged file format which is already supported by U-Boot, and
it supports hierarchy if needed.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Hung-ying Tyan <tyanh@chromium.org>
2014-01-08 17:25:08 -07:00
Simon Glass
5c2859cdc3 sandbox: Allow reading/writing of RAM buffer
It is useful to be able to save and restore the RAM contents of sandbox
U-Boot either for setting up tests, for later analysys, or for chaining
together multiple tests which need to keep the same memory contents.

Add a function to provide a memory file for U-Boot. This is read on
start-up and written when shutting down. If the file does not exist
on start-up, it will be created when shutting down.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-01-08 17:25:03 -07:00
Simon Glass
c5a62d4a7b sandbox: Add -i option to enter interactive mode
Normally when U-Boot starts with a command (-c option) it quits when the
command completes. Normally this is what is requires, since the test is
likely complete.

Provide an option to jump into the console instead, so that debugging or
other tasks may be performed before quitting.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-01-08 17:24:53 -07:00
Simon Glass
91b136c798 sandbox: Allow the console to work earlier
With sandbox, errors and problems may be reported before console_init_f()
is executed. For example, an argument may not parse correctly or U-Boot may
panic(). At present this output is swallowed so there is no indication what
is going wrong.

Adjust the console to deal with a very early sandbox setup, by detecting that
there is no global_data yet, and calling os functions in that case.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-01-08 17:24:50 -07:00
Simon Glass
88bd0e9d15 sandbox: Implement the bootm command for sandbox
When sandbox does a 'bootm' to run a kernel we cannot actually execute it.
So just exit sandbox, which is essentially what U-Boot does on other archs.
Also, allow sandbox to use bootm on any kernel, so that it can be used
to test booting of kernels from any architecture.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-01-08 17:24:42 -07:00
Simon Glass
808434cdbd sandbox: Allow return from board_init_f()
The execution flow becomes easier if we can return from board_init_f()
as ARM does. We can control things from start.c instead of having to
call back into that file from other places.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-01-08 17:24:38 -07:00
Simon Glass
6ebcab8de7 sandbox: Correct help message <arg> garbling
The <arg> is displayed for options with no argument, and omitted for those
with an argument. Swap this around.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2014-01-08 17:24:23 -07:00
Simon Glass
77595c6d9e sandbox: Improve/augment memory allocation functions
Implement realloc() and free() for sandbox, by adding a header to each
block which contains the block size.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Che-Liang Chiou <clchiou@chromium.org>
Reviewed-by: Hung-ying Tyan <tyanh@chromium.org>
2014-01-08 17:24:19 -07:00
Mike Frysinger
6122813fa2 sandbox: spi: Add SPI emulation bus
This adds a SPI framework for people to hook up simulated SPI clients.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2013-12-09 12:22:18 -07:00
Simon Glass
7b3efc6699 sandbox: Rename sb_cmdline_option to sandbox_cmdline_option
The new name is longer but more clearly related to sandbox.

This is in a separate patch within the same series since some comments on the
SPI series rely on it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Hung-ying Tyan <tyanh@chromium.org>
2013-12-09 12:22:02 -07:00
Simon Glass
ed072b96ef sandbox: Make map_to_sysmem() use a constant pointer
Very often a constant pointer is passed to this function, so we should
declare this, since map_to_sysmem() does not change the pointer.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-11-21 16:54:26 -07:00
Simon Glass
0eb2acee39 sandbox: config: Don't use 64-bit physical memory
Sandbox uses an emulated memory map which is quite small. We don't need the
CONFIG_PHYS_64BIT option since we can address memory with a 32-bit offset
into our ram_buf.

Adjust the phys_addr_t and phys_size_t types accordingly.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Hung-ying Tyan <tyanh@chromium.org>
2013-11-21 16:54:26 -07:00
Simon Glass
cbe5cdfcd3 sandbox: Use system headers first for sandbox's os.c
This file must be compiled with system headers, even if U-Boot has headers
of the same name. The existing solution for this is good enough for libfdt,
but fails when we have headers like stdint.h in U-Boot.

Use -idirafter instead of -I, and remove the -nostdinc and other things
that we don't want for this file. The best way to do this is to keep a
copy of the original flags, rather than trying to filter them later.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-11-21 16:54:26 -07:00
Simon Glass
2a54d1599f sandbox: Use uint64_t instead of u64 for time
The uint64_t type is defined in linux/types.h, so is safer than u64, which
is not actually a Linux type.

Change-Id: Ifc9a369e6543250c49117b8d3cb3a676eee43e04
Signed-off-by: Simon Glass <sjg@chromium.org>
2013-11-21 16:54:25 -07:00
Masahiro Yamada
7cf40824be sandbox: convert makefiles to Kbuild style
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
2013-10-31 13:26:44 -04:00
Wolfgang Denk
3765b3e7bd Coding Style cleanup: remove trailing white space
Signed-off-by: Wolfgang Denk <wd@denx.de>
2013-10-14 16:06:53 -04:00
Wolfgang Denk
1a4596601f Add GPL-2.0+ SPDX-License-Identifier to source files
Signed-off-by: Wolfgang Denk <wd@denx.de>
[trini: Fixup common/cmd_io.c]
Signed-off-by: Tom Rini <trini@ti.com>
2013-07-24 09:44:38 -04:00
Simon Glass
e2ee100fd8 sandbox: Support trace feature
Support tracing on sandbox by adding suitable CONFIG options. To enable it,
compile U-Boot with FTRACE=1.

The timer functions are marked to skip tracing, since these are called from
the tracing code itself, and we want to avoid an infinite loop.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-06-26 10:16:41 -04:00
Simon Glass
39042d821e sandbox: Allow -c argument to provide a command list
This allows passing of entire scripts to sandbox with the -c argument,
which is useful for testing. Commands can be delimited with a newline
or semicolon.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-05-01 11:17:21 -04:00
Simon Glass
f828bf25fe sandbox: Add CONFIG_OF_HOSTFILE to read FDT from host file
With sandbox it is tricky to add an FDT to the image at build time (or
later) since we build an ELF file, not a plain binary, and the address
space of the whole U-Boot is not accessible in the emulated memory map
of sandbox.

Sandbox can read files directly from the host, though, so add an option
to read an FDT from a host file on start-up.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-05-01 11:17:21 -04:00
Simon Glass
a733b06b69 sandbox: Switch over to generic board
Add generic board support for sandbox. and remove the old board init code.

Select CONFIG_SYS_GENERIC_BOARD for sandbox now that this is supported.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@ti.com>
2013-05-01 11:17:21 -04:00
Simon Glass
781adb5710 sandbox: Provide a way to map from host RAM to U-Boot RAM
In many cases, pointers to memory are passed around, and these pointers
refer to U-Boot memory, not host memory. This in itself is not a
problem.

However, in a few places, we cast that pointer back to a ulong (being
a U-Boot memory address). It is possible to convert many of these cases
to avoid this. However there are data structures (e.g. struct
bootm_headers) which use pointers. We could with a lot of effort adjust
the structs and all code that uses them to use ulong instead of pointers.

This seems like an unacceptable cost, since our objective with sandbox
is to minimise the impact on U-Boot code while maximising the features
available to sandbox.

Therefore, create a map_to_sysmem() function which converts from a
pointer to a U-Boot address. This can be used sparingly when needed.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-05-01 11:17:21 -04:00
Tom Rini
0ce033d258 Merge branch 'master' of git://git.denx.de/u-boot-arm
Albert's rework of the linker scripts conflicted with Simon's making
everyone use __bss_end.  We also had a minor conflict over
README.scrapyard being added to in mainline and enhanced in
u-boot-arm/master with proper formatting.

Conflicts:
	arch/arm/cpu/ixp/u-boot.lds
	arch/arm/cpu/u-boot.lds
	arch/arm/lib/Makefile
	board/actux1/u-boot.lds
	board/actux2/u-boot.lds
	board/actux3/u-boot.lds
	board/dvlhost/u-boot.lds
	board/freescale/mx31ads/u-boot.lds
	doc/README.scrapyard
	include/configs/tegra-common.h

Build tested for all of ARM and run-time tested on am335x_evm.

Signed-off-by: Tom Rini <trini@ti.com>
2013-03-18 14:37:18 -04:00
Simon Glass
1865286466 Introduce generic link section.h symbol files
We create a separate header file for link symbols defined by the link
scripts. It is helpful to have these all in one place and try to
make them common across architectures. Since Linux already has a similar
file, we bring this in even though many of the symbols there are not
relevant to us.

Each architecture has its own asm/sections.h where symbols specifc to
that architecture can be added. For now everything except AVR32 just
includes the generic header.

One change is needed in arch/avr32/lib/board.c to make this conversion
work.

Reviewed-by: Tom Rini <trini@ti.com> (version 5)
Signed-off-by: Simon Glass <sjg@chromium.org>
2013-03-15 16:13:58 -04:00
Albert ARIBAUD
ef123c5253 Refactor linker-generated arrays
Refactor linker-generated array code so that symbols
which were previously linker-generated are now compiler-
generated. This causes relocation records of type
R_ARM_ABS32 to become R_ARM_RELATIVE, which makes
code which uses LGA able to run before relocation as
well as after.

Note: this affects more than ARM targets, as linker-
lists span possibly all target architectures, notably
PowerPC.

Conflicts:
	arch/arm/cpu/arm926ejs/mxs/u-boot-spl.lds
	arch/arm/cpu/arm926ejs/spear/u-boot-spl.lds
	arch/arm/cpu/armv7/omap-common/u-boot-spl.lds
	board/ait/cam_enc_4xx/u-boot-spl.lds
	board/davinci/da8xxevm/u-boot-spl-da850evm.lds
	board/davinci/da8xxevm/u-boot-spl-hawk.lds
	board/vpac270/u-boot-spl.lds

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2013-03-12 23:28:40 +01:00
Simon Glass
62584db191 sandbox: Add a way of obtaining directory listings
This implementation uses opendir()/readdir() to access the directory
information and then puts it in a linked list for the caller's use.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@ti.com>
2013-03-04 14:19:56 -05:00
Simon Glass
4213fc2913 sandbox: Add un/map_sysmen() to deal with sandbox's ram_buf
Sandbox doesn't actually provide U-Boot access to the machine's physical
memory. Instead it provides a RAM buffer of configurable size, and all
memory accesses are within that buffer. Sandbox memory starts at 0 and
is CONFIG_DRAM_SIZE bytes in size. Allowing access outside this buffer
might produce unpredictable results in the event of an error, and would
expose the host machine's memory architecture to the sandbox U-Boot.

Most U-Boot functions assume that they can just access memory at given
address. For sandbox this is not true.

Add a map_sysmem() call which converts a U-Boot address to a system
address. In most cases this is a NOP, but for sandbox it returns a
pointer to that memory inside the RAM buffer.

To get a U-Boot feature to work correctly within sandbox, you should call
map_sysmem() to get a pointer to the address, and then use that address for
any U-Boot memory accesses.

Signed-off-by: Simon Glass <sjg@chromium.org>
2013-02-28 19:09:22 -08:00
Taylor Hutt
e101550a9a sandbox: Improve sandbox serial port keyboard interface
Implements the tstc() interface for the serial driver.  Multiplexing
the console between the serial port and a keyboard uses a polling
method of checking if characters are available; this means that the
serial console must be non-blocking when attempting to read
characters.

Signed-off-by: Taylor Hutt <thutt@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
2013-02-28 19:09:21 -08:00