Commit Graph

116 Commits

Author SHA1 Message Date
Srinivas Ramana
117e5e9c4c ARM: 8618/1: decompressor: reset ttbcr fields to use TTBR0 on ARMv7
If the bootloader uses the long descriptor format and jumps to
kernel decompressor code, TTBCR may not be in a right state.
Before enabling the MMU, it is required to clear the TTBCR.PD0
field to use TTBR0 for translation table walks.

The commit dbece45894 ("ARM: 7501/1: decompressor:
reset ttbcr for VMSA ARMv7 cores") does the reset of TTBCR.N, but
doesn't consider all the bits for the size of TTBCR.N.

Clear TTBCR.PD0 field and reset all the three bits of TTBCR.N to
indicate the use of TTBR0 and the correct base address width.

Fixes: dbece45894 ("ARM: 7501/1: decompressor: reset ttbcr for VMSA ARMv7 cores")
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Srinivas Ramana <sramana@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-10-02 20:05:14 +01:00
Roy Franz
81a0bc39ea ARM: add UEFI stub support
This patch adds EFI stub support for the ARM Linux kernel.

The EFI stub operates similarly to the x86 and arm64 stubs: it is a
shim between the EFI firmware and the normal zImage entry point, and
sets up the environment that the zImage is expecting. This includes
optionally loading the initrd and device tree from the system partition
based on the kernel command line.

Signed-off-by: Roy Franz <roy.franz@linaro.org>
Tested-by: Ryan Harkin <ryan.harkin@linaro.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2015-12-14 10:38:21 +01:00
Russell King
14327c6628 ARM: replace BSYM() with badr assembly macro
BSYM() was invented to allow us to work around a problem with the
assembler, where local symbols resolved by the assembler for the 'adr'
instruction did not take account of their ISA.

Since we don't want BSYM() used elsewhere, replace BSYM() with a new
macro 'badr', which is like the 'adr' pseudo-op, but with the BSYM()
mechanics integrated into it.  This ensures that the BSYM()-ification
is only used in conjunction with 'adr'.

Acked-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-05-08 17:33:50 +01:00
Joachim Eastwood
c20611df13 ARM: 8327/1: zImage: add support for ARMv7-M
This patch makes it possible to enter zImage in Thumb mode for ARMv7-M
(Cortex-M) CPUs that do not support ARM mode. The kernel entry is also
made in Thumb mode.

[ukl: fix spelling in commit log, return early in call_cache_fn]

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Tested-by: Stefan Agner <stefan@agner.ch>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-03-28 16:54:53 +00:00
Russell King
0a6a78b8b3 ARM: add documentation for finding start of physical memory
Occasionally, there's a question about the method we use to find the
start of physical memory.  Add some documentation so we don't have to
keep repeating outselves on the mailing list.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-03-27 22:21:14 +00:00
Russell King
ed8f8ce38d Merge branches 'debug', 'fixes', 'l2c' (early part), 'misc' and 'sa1100' into for-next 2015-02-10 10:26:27 +00:00
Nicolas Pitre
c2607f74aa ARM: 8294/1: ATAG_DTB_COMPAT: remove the DT workspace's hardcoded 64KB size
There is currently a hardcoded limit of 64KB for the DTB to live in and
be extended with ATAG info.  Some DTBs have outgrown that limit:

$ du -b arch/arm/boot/dts/omap3-n900.dtb
70212   arch/arm/boot/dts/omap3-n900.dtb

Furthermore, the actual size passed to atags_to_fdt() included the stack
size which is obviously wrong.

The initial DTB size is known, so use it to size the allocated workspace
with a 50% growth assumption and relocate the temporary stack above that.
This is also clamped to 32KB min / 1MB max for robustness against bad
DTB data.

Reported-by: Pali Rohár <pali.rohar@gmail.com>
Tested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-01-29 15:23:01 +00:00
Masahiro Yamada
7d57909bf6 ARM: 8290/1: decompressor: fix a wrong comment
This comment does not correspond to the actual code.

When zImage is loaded at a lower *OR* higher address of
the destination of Image, it won't overwrite itself.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-01-21 15:59:34 +00:00
Will Deacon
238962ac71 ARM: 8191/1: decompressor: ensure I-side picks up relocated code
To speed up decompression, the decompressor sets up a flat, cacheable
mapping of memory. However, when there is insufficient space to hold
the page tables for this mapping, we don't bother to enable the caches
and subsequently skip all the cache maintenance hooks.

Skipping the cache maintenance before jumping to the relocated code
allows the processor to predict the branch and populate the I-cache
with stale data before the relocation loop has completed (since a
bootloader may have SCTLR.I set, which permits normal, cacheable
instruction fetches regardless of SCTLR.M).

This patch moves the cache maintenance check into the maintenance
routines themselves, allowing the v6/v7 versions to invalidate the
I-cache regardless of the MMU state.

Cc: <stable@vger.kernel.org>
Reported-by: Marc Carino <marc.ceeeee@gmail.com>
Tested-by: Julien Grall <julien.grall@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-11-13 23:45:20 +00:00
Nicolas Pitre
9696fcae92 ARM: 8079/1: zImage: identify kernel endianness
With patch #8067/1 ("zImage: ensure header in LE format for BE8 kernels")
applied, it is no longer possible to determine the endianness of a compiled
kernel image.  This normally shouldn't matter to the boot environment,
except for those cases where the selection of a ramdisk or root filesystem
with a matching endianness has to be automated.

Let's add a flag to the zImage header indicating the actual endianness.
Four bytes from offset 0x30 can be interpreted as follows:

	04 03 02 01	big endian kernel

	01 02 03 04	little endian kernel

Anything else should be interpreted as "unknown", in which case it is
most likely that patch #8067/1 was not applied either and the zImage
magic number at offset 0x24 could be used instead to determine
endianness. No zImage before this patch ever produced 0x01020304 nor
0x04030201 at offset 0x30 so there is no confusion possible.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 12:29:08 +01:00
Nicolas Pitre
33656d565d ARM: 8067/1: zImage: ensure header in LE format for BE8 kernels
All known BE8-capable systems have LE bootloaders, so we need to ensure
that the magic number and image start/end values are in little endian
format.

[ben.dooks@codethink.co.uk: from nico's original email on this subject]
[taras.kondratiuk@linaro.org: removed lds.S->lds rule, added target to extra-y]

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-01 15:00:28 +01:00
Heiko Stuebner
46f34abc75 ARM: compressed/head.S: remove s3c24xx special case
addruart from the generic debug macro is doing exactly the same using
the common lowlevel uart definition, so there is no cause for this
special casing for s3c24xx.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2014-05-26 04:05:00 +09:00
Ben Dooks
97bcb0fea5 ARM: set BE8 if LE in head code
If we are booting in LE and compiled for BE8, then add code to
set the state to bE8. Since the instruction stream is always LE,
we do not need to do anything special to the instruction.

Also ensure that the secondary processors are started in the same mode.

Note, we do add about 20 bytes to the kernel image, but it seems easier
to do this than adding another configuration to change.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2013-10-19 20:46:33 +01:00
Ben Dooks
457c2403c5 ARM: asm: Add ARM_BE8() assembly helper
Add ARM_BE8() helper to wrap any code conditional on being
compile when CONFIG_ARM_ENDIAN_BE8 is selected and convert
existing places where this is to use it.

Acked-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
2013-10-19 20:46:33 +01:00
Russell King
cbd379b100 Merge branches 'fixes', 'mcpm', 'misc' and 'mmci' into for-next 2013-06-29 11:43:28 +01:00
Marc Zyngier
52c08a9e39 ARM: 7770/1: remove residual ARMv2 support from decompressor
arm26 support in Linux is long gone, yet it left an interresting,
fossilized trace in the decompressor.

Remove it so people won't get confused about what teqp is actually
doing here...

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-06-24 15:28:24 +01:00
Nicolas Pitre
2874865c12 ARM: 7751/1: zImage: don't overwrite ourself with a page table
When zImage is loaded into RAM at a low address but TEXT_OFFSET
is set higher, we risk overwriting ourself with the page table
needed to turn on the cache as it is located relative to the relocation
address.  Let's defer the cache setup after relocation in that case.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Reported-by: Stephen Boyd <sboyd@codeurora.org>
Tested-by: Stephen Boyd <sboyd@codeurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-06-17 09:27:05 +01:00
Marc C
ced2a3b849 ARM: 7750/1: update legacy CPU ID in decompressor cache support jump table
The previous mask values for the legacy ARM CPU IDs were conflicting
with the CPU ID assignments for late-generation CPUs (like the
Qualcomm MSM/QSD or Broadcom Brahma-15 processors). This change
corrects the legacy ARM CPU ID value so that the jump table can
fall-through to the appropriate cache maintenance / MMU functions.

Signed-off-by: Marc C <marc.ceeeee@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-06-05 23:32:40 +01:00
Arnd Bergmann
da94a82930 ARM: 7743/1: compressed/head.S: work around new binutils warning
In August 2012, Matthew Gretton-Dann checked a change into binutils
labelled "Error on obsolete & warn on deprecated registers", apparently as
part of ARMv8 support. Apparently, this was supposed to emit the message
"Warning: This coprocessor register access is deprecated in ARMv8" when
using certain mcr/mrc instructions and building for ARMv8. Unfortunately,
the message that is actually emitted appears to be '(null)', which is
less helpful in comparison.

Even more unfortunately, this is biting us on every single kernel
build with a new gas, because arch/arm/boot/compressed/head.S and some
other files in that directory are built with -march=all since kernel
commit 80cec14a8 "[ARM] Add -march=all to assembly file build in
arch/arm/boot/compressed" back in v2.6.28.

This patch reverts Russell's nice solution and instead marks the head.S
file to be built for armv7-a, which fortunately lets us build all
instructions in that file without warnings even on the broken binutils.

Without this patch, building anything results in:

arch/arm/boot/compressed/head.S: Assembler messages:
arch/arm/boot/compressed/head.S:565: Warning: (null)
arch/arm/boot/compressed/head.S:676: Warning: (null)
arch/arm/boot/compressed/head.S:698: Warning: (null)
arch/arm/boot/compressed/head.S:722: Warning: (null)
arch/arm/boot/compressed/head.S:726: Warning: (null)
arch/arm/boot/compressed/head.S:957: Warning: (null)
arch/arm/boot/compressed/head.S:996: Warning: (null)
arch/arm/boot/compressed/head.S:997: Warning: (null)
arch/arm/boot/compressed/head.S:1027: Warning: (null)
arch/arm/boot/compressed/head.S:1035: Warning: (null)
arch/arm/boot/compressed/head.S:1046: Warning: (null)
arch/arm/boot/compressed/head.S:1060: Warning: (null)
arch/arm/boot/compressed/head.S:1092: Warning: (null)
arch/arm/boot/compressed/head.S:1094: Warning: (null)
arch/arm/boot/compressed/head.S:1095: Warning: (null)
arch/arm/boot/compressed/head.S:1102: Warning: (null)
arch/arm/boot/compressed/head.S:1134: Warning: (null)

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org
Cc: Matthew Gretton-Dann <matthew.gretton-dann@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-06-05 23:32:27 +01:00
Shawn Guo
4beba08ba1 ARM: 7600/1: include CONFIG_DEBUG_LL_INCLUDE rather than mach/debug-macro.S
Commit 91a9fec (ARM: move debug macros to common location) moves
arch/arm/kernel/debug.S and arch/arm/kernel/head.S to
CONFIG_DEBUG_LL_INCLUDE, but leaves arch/arm/boot/compressed/head.S
still with mach/debug-macro.S.  This causes the following build error
on platforms that moved to new DEBUG_LL inclusion mechanism, when
arch/arm/boot/compressed/head.S is compiled with DEBUG turned on.

  AS      arch/arm/boot/compressed/head.o
arch/arm/boot/compressed/head.S:49:30: fatal error: mach/debug-macro.S: No such file or directory
compilation terminated.

Fix the problem by replacing mach/debug-macro.S inclusion with
CONFIG_DEBUG_LL_INCLUDE one.

Reported-by: Steev Klimaszewski <steev@genesi-usa.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-12-16 10:04:23 +00:00
Dave Martin
5010192d5a ARM: 7583/1: decompressor: Enable unaligned memory access for v6 and above
Modern GCC can generate code which makes use of the CPU's native
unaligned memory access capabilities.  This is useful for the C
decompressor implementations used for unpacking compressed kernels.

This patch disables alignment faults and enables the v6 unaligned
access model on CPUs which support these features (i.e., v6 and
later), allowing full unaligned access support for C code in the
decompressor.

The decompressor C code must not be built to assume that unaligned
access works if support for v5 or older platforms is included in
the kernel.

For correct code generation, C decompressor code must always use
the get_unaligned and put_unaligned accessors when dealing with
unaligned pointers, regardless of this patch.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-23 13:02:03 +00:00
Russell King
648f3b6998 Merge branch 'hyp-boot-mode-rmk' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into devel-stable 2012-09-30 09:03:44 +01:00
Dave Martin
424e5994e6 ARM: zImage/virt: hyp mode entry support for the zImage loader
The zImage loader needs to turn on the MMU in order to take
advantage of caching while decompressing the zImage.  Running this
in hyp mode would require the LPAE pagetable format to be
supported; to avoid this complexity, this patch switches out of hyp
mode, and returns back to hyp mode just before booting the kernel.

This implementation assumes that the Hyp mode view of memory and the
PL1 view of memory are coherent, providing that the MMU and caches
are off in both, as required by the boot protocol.  The zImage
decompression code must drain the write buffer on completion anyway, and
entry into Hyp mode should flush any prefetch buffer, avoiding hazards
associated with local write buffers and the pipeline.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-09-19 08:32:50 +01:00
Matthew Leach
e1e5b7e425 ARM: 7532/1: decompressor: reset SCTLR.TRE for VMSA ARMv7 cores
This patch zeroes the SCTLR.TRE bit prior to setting the mapping as
cacheable for ARMv7 cores in the decompressor, ensuring that the
memory region attributes are obtained from the C and B bits, not from
the page tables.

Cc: Nicolas Pitre <nico@fluxnic.net>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-09-16 00:16:16 +01:00
Will Deacon
dbece45894 ARM: 7501/1: decompressor: reset ttbcr for VMSA ARMv7 cores
When enabling the MMU for ARMv7 CPUs, the decompressor does not touch
the ttbcr register, assuming that it will be zeroed (N == 0, EAE == 0).
Given that only EAE is defined as 0 for non-secure copies of the
register (and a bootloader such as kexec may leave it set to 1 anyway),
we should ensure that we reset the register ourselves before turning on
the MMU.

This patch zeroes TTBCR.EAE and TTBCR.N prior to enabling the MMU for
ARMv7 cores in the decompressor, configuring us exclusively for 32-bit
translation tables via TTBR0.

Cc: <stable@vger.kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-08-25 09:15:56 +01:00
Russell King
4ab1056766 Merge branch 'v3-removal' into for-linus
Conflicts:
	arch/arm/boot/compressed/head.S
2012-05-21 15:15:33 +01:00
Russell King
1fdc08abfa ARM: decompressor: avoid speculative prefetch from non-RAM areas
We setup identity MMU mappings across the entire 4GB of space, which
are permissionless because the domain is set to manager.

This unfortunately allows ARMv6 and later CPUs to speculatively
prefetch from the entire address space, which can cause undesirable
side effects if those regions contain devices.

As we setup the mappings with read/write permission, we can switch
the domain to client mode, and then use the XN bit for ARMv6 and
above to control speculative prefetch to non-RAM areas.

Reported-by: R Sricharan <r.sricharan@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-05-10 09:48:34 +01:00
Russell King
4cdfc2ec72 ARM: Remove ARMv3 support from decompressor
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-05-09 15:18:19 +01:00
Marc Zyngier
9c5fd9e85f ARM: 7379/1: DT: fix atags_to_fdt() second call site
atags_to_fdt() returns 1 when it fails to find a valid FDT signature.
The CONFIG_ARM_ATAG_DTB_COMPAT code is supposed to retry with another
location, but only does so when the initial call doesn't fail.

Fix this by using the correct condition in the assembly code.

Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-04-13 14:05:41 +01:00
Kukjin Kim
b130d5c295 ARM: S3C24XX: change the ARCH_S3C2410 to ARCH_S3C24XX
This patch changes the ARCH name to "ARCH_S3C24XX" for Samsung
S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443,
and S3C2450 SoCs so that we can merge the mach-xxx directories
and plat-s3c24xx dir. to just one mach-s3c24xx for them.

I think this should be sent to upstream via samsung tree because
this touches many samsung stuff.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Ball <cjb@laptop.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
[for the gadget part:]
Acked-by: Felipe Balbi <balbi@ti.com>
[for the framebuffer (video) part:]
Acked-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
[For the watchdog-part:]
Acked-by: Wim Van Sebroeck <wim@iguana.be>
Cc: Sangbeom Kim <sbkim73@samsung.com>
Cc: Liam Girdwood <lrg@ti.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-03-03 07:44:51 +09:00
Will Deacon
d675d0bc47 ARM: LPAE: add ISBs around MMU enabling code
Before we enable the MMU, we must ensure that the TTBR registers contain
sane values. After the MMU has been enabled, we jump to the *virtual*
address of the following function, so we also need to ensure that the
SCTLR write has taken effect.

This patch adds ISB instructions around the SCTLR write to ensure the
visibility of the above.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-12-08 10:30:38 +00:00
Nicolas Pitre
531a6a9417 ARM: 7139/1: fix compilation with CONFIG_ARM_ATAG_DTB_COMPAT and large TEXT_OFFSET
If TEXT_OFFSET is too large (e.g. like on MSM) the resulting immediate
argument gets wider than 8 bits.

Noticed by David Brown <davidb@codeaurora.org>

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-24 20:53:50 +01:00
Nicolas Pitre
b90b9a3825 ARM: zImage: allow supplementing appended DTB with traditional ATAG data
Some old bootloaders can't be updated to a device tree capable one,
yet they provide ATAGs with memory configuration, the ramdisk address,
the kernel cmdline string, etc.  To allow a device tree enabled
kernel to be used with such bootloaders, it is necessary to convert those
ATAGs into FDT properties and fold them into the DTB appended to zImage.

Currently the following ATAGs are converted:

	ATAG_CMDLINE
	ATAG_MEM
	ATAG_INITRD2

If the corresponding information already exists in the appended DTB, it
is replaced, otherwise the required node is created to hold it.

The code looks for ATAGs at the location pointed by the value of r2 upon
entry into the zImage code.  If no ATAGs are found there, an attempt at
finding ATAGs at the typical 0x100 offset from start of RAM is made.
Otherwise the DTB is left unchanged.

Thisstarted from an older patch from John Bonesio <bones@secretlab.ca>,
with contributions from David Brown <davidb@codeaurora.org>.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Thomas Abraham <thomas.abraham@linaro.org>
2011-09-14 13:51:59 -04:00
Nicolas Pitre
5ffb04f669 ARM: zImage: make sure appended DTB doesn't get overwritten by kernel .bss
The appended DTB gets relocated with the decompressor code to get out
of the way of the decompressed kernel.  However the kernel's .bss section
may be larger than the relocated code and data, and then the DTB gets
overwritten.  Let's make sure the relocation takes care of moving zImage
far enough so no such conflict with .bss occurs.

Thanks to Tony Lindgren <tony@atomide.com> for figuring out this issue.

While at it, let's clean up the code a bit so that the wont_overwrite
symbol is used while determining if a conflict exists, making the above
change more precise as well as eliminating some ARM/THUMB alternates.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Thomas Abraham <thomas.abraham@linaro.org>
2011-09-14 13:51:57 -04:00
John Bonesio
e2a6a3aafa ARM: zImage: Allow the appending of a device tree binary
This patch provides the ability to boot using a device tree that is appended
to the raw binary zImage (e.g. cat zImage <filename>.dtb > zImage_w_dtb).

Signed-off-by: John Bonesio <bones@secretlab.ca>
[nico: ported to latest zImage changes plus additional cleanups/improvements]
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Thomas Abraham <thomas.abraham@linaro.org>
2011-09-14 13:50:45 -04:00
Russell King
06f365acef Merge branches 'btc', 'dma', 'entry', 'fixes', 'linker-layout', 'misc', 'mmci', 'suspend' and 'vfp' into for-next 2011-07-22 23:08:48 +01:00
Dave Martin
540b573875 ARM: 6999/1: head, zImage: Always Enter the kernel in ARM state
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>
2011-07-19 12:00:53 +01:00
Dave Martin
946a105e16 ARM: 6961/1: zImage: Add build-time check for correctly-sized proc_type entries
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>
2011-06-21 11:33:20 +01:00
Nicolas Pitre
720c60e194 ARM: 6954/1: zImage: fix Thumb2 breakage
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>
2011-06-09 10:15:06 +01:00
Russell King
9a55d9752d Merge branch 'devel-stable' into for-linus
Conflicts:
	arch/arm/Kconfig
	arch/arm/mach-ns9xxx/include/mach/uncompress.h
2011-05-23 19:28:04 +01:00
Russell King
ec19628d72 Merge branches 'consolidate', 'ep93xx', 'fixes', 'misc', 'mmci', 'remove' and 'spear' into for-linus 2011-05-23 19:27:40 +01:00
Mark A. Greer
af3e4fd37a ARM: 6859/1: Add writethrough dcache support for ARM926EJS processor
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>
2011-05-12 10:07:00 +01:00
Russell King
362607df9f Merge first four commits of 'zImage_fixes' of git://git.linaro.org/people/nico/linux into fixes 2011-05-07 08:34:40 +01:00
Russell King
7b76415375 Merge branch 'zImage_fixes' of git://git.linaro.org/people/nico/linux into devel-stable 2011-05-07 08:34:02 +01:00
Nicolas Pitre
8d7e4cc2c8 ARM: zImage: make sure no GOTOFF relocs are used with .bss symbols
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>
2011-05-07 00:08:03 -04:00
Nicolas Pitre
34cc1a8fe0 ARM: zImage: no need to get the decompressed size from the filesystem
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>
2011-05-07 00:07:59 -04:00
Nicolas Pitre
ea9df3b168 ARM: zImage: the page table memory must be considered before relocation
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>
2011-05-07 00:07:58 -04:00
Nicolas Pitre
adcc25915b ARM: zImage: make sure not to relocate on top of the relocation code
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>
2011-05-07 00:07:53 -04:00
Tony Lindgren
7c2527f0c4 ARM: zImage: Fix bad SP address after relocating kernel
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>
2011-05-06 23:56:43 -04:00
Nicolas Pitre
f5178ddd2f ARM: PJ4: remove the ARMv6 compatible cache method entries
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>
2011-05-03 15:39:05 -04:00