Currently, the documented kernel entry requirements are not
explicit about whether the kernel should be entered in ARM or
Thumb, leading to an ambiguitity about how to enter Thumb-2
kernels. As a result, the kernel is reliant on the zImage
decompressor to enter the kernel proper in the correct instruction
set state.
This patch changes the boot entry protocol for head.S and Image to
be the same as for zImage: in all cases, the kernel is now entered
in ARM.
Documentation/arm/Booting is updated to reflect this new policy.
A different rule will be needed for Cortex-M class CPUs as and when
support for those lands in mainline, since these CPUs don't support
the ARM instruction set at all: a note is added to the effect that
the kernel must be entered in Thumb on such systems.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Place read-only data in a .rodata output section, and the compressed
piggy data in .piggydata. Place the .got.plt section before the .got
section as is standard ELF practise.
This allows the piggydata to be more easily extracted from the
compressed vmlinux file for verification purposes.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows a ROM-able zImage to be written to eSD and for SuperH Mobile
ARM to boot directly from the SDHI hardware block.
This is achieved by the MaskROM loading the first portion of the image into
MERAM and then jumping to it. This portion contains loader code which
copies the entire image to SDRAM and jumps to it. From there the zImage
boot code proceeds as normal, uncompressing the image into its final
location and then jumping to it.
Cc: Paul Mundt <lethal@linux-sh.org>
Acked-by: Magnus Damm <magnus.damm@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
It is easy to mis-maintain the proc_types table such that the
entries become wrongly-sized and misaligned when the kernel is
built in Thumb-2.
This patch adds an assembly-time check which will turn most common
size/alignment mistakes in this table into build failures, to avoid
having to debug the boot-time kernel hang which would happen if the
resulting kernel were actually booted.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Commit af3e4fd37a "ARM: 6859/1: Add writethrough dcache support for
ARM926EJS processor" broke Thumb2 compilation by omitting to maintain
the wide encoding for the added branch instructions which made the
ARM926EJ-S record smaller than expected, breaking the record walk code.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Cc: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ARM kernel supports writethrough data cache via the
CONFIG_CPU_DCACHE_WRITETHROUGH option. However, that
functionality wasn't implemented in the arch/arm/boot/compressed
code. It is now necessary due to a new ARM926EJS processor
that has an issue with writeback data cache.
Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
To be able to relocate the .bss section at run time independently from
the rest of the code, we must make sure that no GOTOFF relocations are
used with .bss symbols. This usually means that no global variables can
be marked static unless they're also const.
To enforce this, suffice to fail the build whenever a private symbol
is allocated to .bss and list those symbols for convenience.
The user_stack and user_stack_end labels in head.S were converted into
non exported symbols to remove false positives.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
If decompress() returns an error without calling error(), we must
not attempt to boot the resulting kernel.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
The return value for decompress_kernel() is no longer used. Furthermore,
this was obtained and stored in a variable called output_ptr which is
a complete misnomer for what is actually the size of the decompressed
kernel image. Let's get rid of it.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
In commit d239b1dc09 the hardcoded 4x estimate for the decompressed
kernel size was replaced by the exact Image file size and passed to
the linker as a symbol value. Turns out that this is unneeded as the
size is already included at the end of the compressed piggy data.
For those compressed formats that don't include this data, the build
system already takes care of appending it using size_append in
scripts/Makefile.lib. So let's use that instead.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
For correctness, the initial page table located right before the
decompressed kernel should be considered when determining if relocation
is required.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
If the zImage load address is slightly below the relocation address,
there is a risk for the copied data to overwrite the copy loop or
cache flush code that the relocation process requires. Always
bump the relocation address by the size of that code to avoid this
issue.
Noticed by Tony Lindgren <tony@atomide.com>.
While at it, let's start the copy from the restart symbol which makes
the above code size computation possible by the assembler directly
(same sections), given that we don't need to preserve the code before
that point anyway. And therefore we don't need to carry the _start
pointer in r5 anymore.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Otherwise cache_clean_flush can overwrite some of the relocated
area depending on where the kernel image gets loaded. This fixes
booting on n900 after commit 6d7d0ae515
(ARM: 6750/1: improvements to compressed/head.S).
Thanks to Aaro Koskinen <aaro.koskinen@nokia.com> for debugging
the address of the relocated area that gets corrupted, and to
Nicolas Pitre <nicolas.pitre@linaro.org> for the other uncompress
related fixes.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
With ARMv5+ and EABI, the compiler expects a 64-bit aligned stack so
instructions like STRD and LDRD can be used. Without this, mysterious
boot failures were seen semi randomly with the LZMA decompressor.
While at it, let's align .bss as well.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
CC: stable@kernel.org
The Marvell PJ4 is ARMv7 capable, so we don't support it in
ARMv6 mode anymore.
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Acked-by: Saeed Bishara <saeed.bishara@gmail.com>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
The inline assembly differences for v6 vs. v7 are purely
optimizations. On a v7 processor, an mrc with the pc sets the
condition codes to the 28-31 bits of the register being read. It
just so happens that the TX/RX full bits the DCC support code is
testing for are high enough in the register to be put into the
condition codes. On a v6 processor, this "feature" isn't
implemented and thus we have to do the usual read, mask, test
operations to check for TX/RX full. Thus, we can drop the v7
implementation and just use the v6 implementation for both.
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This is my second attempt to make this enum generally available.
The first attempt added MMCIF_PROGRESS_* to include/linux/mmc/sh_mmcif.h.
However this is not sufficiently generic as the enum will be
used by SDHI boot code.
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
These headers and helpers will also be used for SDHI boot
so the mmcif name will start to make a lot less sense.
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: (25 commits)
video: change to new flag variable
scsi: change to new flag variable
rtc: change to new flag variable
rapidio: change to new flag variable
pps: change to new flag variable
net: change to new flag variable
misc: change to new flag variable
message: change to new flag variable
memstick: change to new flag variable
isdn: change to new flag variable
ieee802154: change to new flag variable
ide: change to new flag variable
hwmon: change to new flag variable
dma: change to new flag variable
char: change to new flag variable
fs: change to new flag variable
xtensa: change to new flag variable
um: change to new flag variables
s390: change to new flag variable
mips: change to new flag variable
...
Fix up trivial conflict in drivers/hwmon/Makefile
Replace EXTRA_CFLAGS with ccflags-y and EXTRA_AFLAGS with asflags-y.
Signed-off-by: matt mooney <mfm@muteddisk.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
The simply expanded variable may be evaluated before the target file for
the stat command is up to date or even exists. Switching to a recursively
expanded variable move the execution of the stat command to the location
where LDFLAGS_vmlinux is actually used, fixing the dependency issue
introduced by patch #6746/1.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We currently presume a 4x expansion to guess the decompressed kernel size
in order to determine if the decompressed kernel is in conflict with
the location where zImage is loaded. This guess may cause many issues
by overestimating the final kernel image size:
- This may force a needless relocation if the location of zImage was
fine, wasting some precious microseconds of boot time.
- The relocation may be located way too far, possibly overwriting the
initrd image in RAM.
- If the kernel image includes a large already-compressed initramfs image
then the problem is even more exacerbated.
And if by some strange means the 4x guess is too low then we may overwrite
ourselves with the decompressed image.
So let's use the exact decompressed kernel image size instead. For that
we need to rely on the stat command, but this is hardly a new build
dependency as the kernel already depends on many external commands
to be built provided by the coreutils package where stat is found.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In the case of a conflict between the memory used by the compressed
kernel with its decompressor code and the memory used for the
decompressed kernel, we currently store the later after the former and
relocate it afterwards.
This would be more efficient to do this the other way around i.e.
relocate the compressed data up front instead, resulting in a smaller
copy. That also has the advantage of making the code smaller and more
straight forward.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Some installers would binary patch the kernel zImage to replace the
first few nops with custom instructions. This breaks the Thumb2 kernel
as the mode switch is right at the beginning. Let's move it towards the
end of the nop sequence instead.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We have 'install' and 'zinstall' for installing Image and zImage
kernels, so add 'uinstall' to complete the set.
This allows developers to have a ~/bin/installkernel script which (eg)
copies the kernel to the tftp server automatically once the kernel
has built, resulting in a better workflow.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Introduce a CPU_V6K configuration option for platforms to select if they
have a V6K CPU core. This allows us to identify whether we need to
support ARMv6 CPUs without the V6K SMP extensions at build time.
Currently CPU_V6K is just an alias for CPU_V6, and all places which
reference CPU_V6 are replaced by (CPU_V6 || CPU_V6K).
Select CPU_V6K from platforms which are known to be V6K-only.
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Sourav Poddar <sourav.poddar@ti.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This adds support for the family of Systems-on-Chip produced initially
by VIA and now its subsidiary WonderMedia that have recently become
widespread in lower-end Chinese ARM-based tablets and netbooks.
Support is included for both VT8500 and WM8505, selectable by a
configuration switch at kernel build time.
Included are basic machine initialization files, register and
interrupt definitions, support for the on-chip interrupt controller,
high-precision OS timer, GPIO lines, necessary macros for early debug,
pulse-width-modulated outputs control, as well as platform device
configurations for the specific drivers implemented elsewhere.
Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This allows a ROM-able zImage to be written to MMC and
for SuperH Mobile ARM to boot directly from the MMCIF
hardware block.
This is achieved by the MaskROM loading the first portion
of the image into MERAM and then jumping to it. This portion
contains loader code which copies the entire image to SDRAM
and jumps to it. From there the zImage boot code proceeds
as normal, uncompressing the image into its final location
and then jumping to it.
Cc: Magnus Damm <magnus.damm@gmail.com>
Russell, please consider merging this for 2.6.38.
This patch depends on:
* "mmc, sh: Move MMCIF_PROGRESS_* into sh_mmcif.h"
which will be merged though Paul Mundt's rmobile sh-2.6.
The absence of this patch will break the build if
the (new) CONFIG_ZBOOT_ROM_MMCIF option is set.
There are no subtle side-effects.
v2:
Addressed comments by Magnus Damm
* Fix copyright in vrl4.c
* Fix use of #define CONFIG_ZBOOT_ROM_MMCIF in mmcif-sh7372.c
* Initialise LED GPIO lines in head-ap4evb.txt instead of mmcif-sh7372.c
as this is considered board-specific.
v3:
Addressed comments made in person by Magnus Damm
* Move mmcif_loader to be earlier in the image and
reduce the number of blocks of boot program loaded by the MaskRom
from 40 to 8 accordingly.
* Move LED GPIO initialisation into mmcif_progress_init
- This leaves the partner jet script unbloated
Other
* inline mmcif_update_progress so it is a static inline in a header file
v4:
* Use htole16() and htole32() in v4rl.c to ensure
that the output is little endian
v5:
Addressed comments by Russell King
* Simplify assembly code
* Jump to code rather than an address <- bug fix
* Use (void __iomem *) as appropriate
Roll in mackerel support
* This was previously a separate patch, only because of the order
in which this code was developed
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When CONFIG_ZBOOT_ROM is selected, the resulting zImage file will be small
boot loader and may be burned to rom or flash.
This is the non-board-specific framework portion of this patch-set.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The code which makes up the zImage header intends to leave a
32-byte gap followed by a branch to the real entry point, a magic
number, and a word containing the absolute entry point address.
This gets messed up with with CONFIG_THUMB2_KERNEL, because the
size of the initial padding NOPs changes.
Instead, the header can be made fully compatible by restoring it to
ARM.
In the Thumb-2 case, we can replace the initial NOPs with a
sequence which switches to Thumb and jumps to the real entry point.
As a consequence, the zImage entry point is now always ARM, so no
special magic is needed any more for the uImage rules in the
Thumb-2 case.
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Some instruction operand combinations are used here which are nor
permitted in Thumb-2.
In particular, most uses of pc as an operand are disallowed in
Thumb-2, and deprecated in ARM from ARMv7 onwards.
The modified code introduced by this patch should be compatible
with all architecture versions >= v3, with or without
CONFIG_THUMB2_KERNEL.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Directives such as .long and .word do not magically cause the
assembler location counter to become aligned in gas. As a result,
using these directives in code sections can result in misaligned
data words when building a Thumb-2 kernel (CONFIG_THUMB2_KERNEL).
This is a Bad Thing, since the ABI permits the compiler to assume
that fundamental types of word size or above are word- aligned when
accessing them from C. If the data is not really word-aligned,
this can cause impaired performance and stray alignment faults in
some circumstances.
In general, the following rules should be applied when using data
word declaration directives inside code sections:
* .quad and .double:
.align 3
* .long, .word, .single, .float:
.align (or .align 2)
* .short:
No explicit alignment required, since Thumb-2
instructions are always 2 or 4 bytes in size.
immediately after an instruction.
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The .stack section doesn't contain any contents, and doesn't require
initialization either. Rather than marking the output section with
'NOLOAD' but still having it exist in the object files, mark it with
%nobits which avoids the assembler marking the section with 'CONTENTS'.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Jonathan Cameron reports that when using the environment
variable KCONFIG_CONFIG, he encounters this error:
make[2]: *** No rule to make target `.config', needed by `arch/arm/boot/compressed/vmlinux.lds'
Reported-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Partially revert e69edc7, which introduced automatic zreladdr
support. The change in the way the manual definition is defined
seems to be error and conflict prone. Go back to the original way
we were handling this for the time being, while keeping the automatic
zreladdr facility.
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
"ARM: Auto calculate ZRELADDR and provide option for exceptions" broke
the Thumb-2 decompressor because it removed an entry in the LC0 table
but didn't adjust the offset the Thumb-2 code uses to load the SP from
that table.
Fix it, and also change the ARM code to use the separate SP-load since
ARM instructions that include the SP in the LDM register list are
deprecated.
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
With kexec-based kernel boot loader on Zaurus, the machine ID is
actually correctly passed, and head-sharpsl.S is not necessary.
Introduce PXA_SHARPSL_DETECT_MACH_ID, and include head-sharpsl.S
only when that's explicitly enabled.
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (291 commits)
ARM: AMBA: Add pclk support to AMBA bus infrastructure
ARM: 6278/2: fix regression in RealView after the introduction of pclk
ARM: 6277/1: mach-shmobile: Allow users to select HZ, default to 128
ARM: 6276/1: mach-shmobile: remove duplicate NR_IRQS_LEGACY
ARM: 6246/1: mmci: support larger MMCIDATALENGTH register
ARM: 6245/1: mmci: enable hardware flow control on Ux500 variants
ARM: 6244/1: mmci: add variant data and default MCICLOCK support
ARM: 6243/1: mmci: pass power_mode to the translate_vdd callback
ARM: 6274/1: add global control registers definition header file for nuc900
mx2_camera: fix type of dma buffer virtual address pointer
mx2_camera: Add soc_camera support for i.MX25/i.MX27
arm/imx/gpio: add spinlock protection
ARM: Add support for the LPC32XX arch
ARM: LPC32XX: Arch config menu supoport and makefiles
ARM: LPC32XX: Phytec 3250 platform support
ARM: LPC32XX: Misc support functions
ARM: LPC32XX: Serial support code
ARM: LPC32XX: System suspend support
ARM: LPC32XX: GPIO, timer, and IRQ drivers
ARM: LPC32XX: Clock driver
...
