powerpc/boot: Use address-of operator on section symbols

Clang warns:

arch/powerpc/boot/main.c:107:18: warning: array comparison always
evaluates to a constant [-Wtautological-compare]
if (_initrd_end > _initrd_start) {
^
arch/powerpc/boot/main.c:155:20: warning: array comparison always
evaluates to a constant [-Wtautological-compare]
if (_esm_blob_end <= _esm_blob_start)
^
2 warnings generated.

These are not true arrays, they are linker defined symbols, which are
just addresses. Using the address of operator silences the warning
and does not change the resulting assembly with either clang/ld.lld
or gcc/ld (tested with diff + objdump -Dr).

Reported-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200624035920.835571-1-natechancellor@gmail.com

powerpc: Add support for adding an ESM blob to the zImage wrapper

For secure VMs, the signing tool will create a ticket called the "ESM blob"
for the Enter Secure Mode ultravisor call with the signatures of the kernel
and initrd among other things.

This adds support to the wrapper script for adding that blob via the "-e"
option to the zImage.pseries.

It also adds code to the zImage wrapper itself to retrieve and if necessary
relocate the blob, and pass its address to Linux via the device-tree, to be
later consumed by prom_init.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[ bauerman: Minor adjustments to some comments. ]
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-4-bauerman@linux.ibm.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

powerpc/boot: Fix the early OPAL console wrappers

When configured with CONFIG_PPC_EARLY_DEBUG_OPAL=y the kernel expects
the OPAL entry and base addresses to be passed in r8 and r9
respectively. Currently the wrapper does not attempt to restore these
values before entering the decompressed kernel which causes the kernel
to branch into whatever happens to be in r9 when doing a write to the
OPAL console in early boot.

This patch adds a platform_ops hook that can be used to branch into the
new kernel. The OPAL console driver patches this at runtime so that if
the console is used it will be restored just prior to entering the
kernel.

Fixes: 656ad58ef19e ("powerpc/boot: Add OPAL console to epapr wrappers")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/boot: Fix boot on systems with uncompressed kernel image

This commit broke boot on systems with an uncompressed kernel image,
namely systems using a cuImage. On such systems the compressed boot
image (boot wrapper, uncompressed kernel image, ..) is decompressed
by u-boot already, therefore the boot wrapper code sees an
uncompressed kernel image.

The old decompression code silently assumed an uncompressed kernel
image if it found no valid gzip signature, whilst the new code
bailed out in this case.

Fix this by re-introducing such a fallback if no valid compressed
image is found.

Fixes: 1b7898ee276b ("Use the pre-boot decompression API")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/boot: Use the pre-boot decompression API

Currently the powerpc boot wrapper has its own wrapper around zlib to
handle decompressing gzipped kernels. The kernel decompressor library
functions now provide a generic interface that can be used in the
pre-boot environment. This allows boot wrappers to easily support
different compression algorithms. This patch converts the wrapper to use
this new API, but does not add support for using new algorithms.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/boot: Parse chosen/cmdline-timeout parameter

On some platforms a 5 second timeout during boot might be quite long, so
make it configurable. Run the loop at least once to let the user stop
the boot by holding a key pressed. If the timeout is set to 0, don't
wait for input, which can be used as a workaround if the boot hangs on
random data coming in on the serial port.

Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
[mpe: Changelog wording & whitespace]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: Rename duplicate COMMAND_LINE_SIZE define

We have two definitions of COMMAND_LINE_SIZE, one for the kernel
and one for the boot wrapper. I assume this is so the boot
wrapper can be self sufficient and not rely on kernel headers.

Having two defines with the same name is confusing, I just
updated the wrong one when trying to bump it.

Make the boot wrapper define unique by calling it
BOOT_COMMAND_LINE_SIZE.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Fix format string warning in arch/powerpc/boot/main.c

Fix format string warning in arch/powerpc/boot/main.c. Also correct
a typo ("uncomressed") on the same line.

BOOTCC arch/powerpc/boot/main.o
arch/powerpc/boot/main.c: In function 'prep_kernel':
arch/powerpc/boot/main.c:65: warning: format '%08x' expects type
'unsigned int', but argument 3 has type 'long unsigned int'

Signed-off-by: Jon Smirl <jonsmirl@gmail.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

powerpc/boot: Compare _start against ei.loadsize instead ei.memsize

If the vmlinux binary in memory is larger than 4 MiB than it collides
with the initial boot code which is linked at 4 MiB in case of cuBoot.
If the the uncompressed image size (on disk size) is less than 4 MiB
then it would fit. The difference between those two sizes is the bss
section. In cuBoot we have the dtb embedded right after the data
section so it is very likely that the reset of the bss section (in
kernel's start up code) will overwrite the dtb blob. Therefore we
reallocate the dtb. Something similar is allready done to the initrd.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

[POWERPC] Kill flatdevtree.c

Now that earlier patches have switched the bootwrapper to using libfdt
for device tree manipulation, this patch removes the now unused
flatdevtree.c and related files.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] bootwrapper: Move linker symbols into ops.h

Most of these were previously used by numerous C files and
redeclared in each one.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] Make kernel_entry_t have global scope in bootwrapper

For the convenience of custom platform code make the powerpc
bootwrapper typdef kernel_entry_t global in scope.

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] bootwrapper: Decompress less, check more

Our kernels put everything in the first load segment, and we read that.
Instead of decompressing to the end of the gzip stream or supplied image
and hoping we get it all, decompress the expected size and complain if
it is not available.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] Move bootwrapper ELF parsing routines to a file

The ELF parsing routines local to arch/powerpc/boot/main.c are useful
to other callers therefore move them to their own file.

Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] Clean up zImage handling of the command line

This cleans up how the zImage code manipulates the kernel
command line. Notable improvements from the old handling:
- Command line manipulation is consolidated into a new
prep_cmdline() function, rather than being scattered across start()
and some helper functions
- Less stack space use: we use just a single global command
line buffer, which can be initialized by an external tool as before,
we no longer need another command line sized buffer on the stack.
- Easier to support platforms whose firmware passes a
commandline, but not a device tree. Platform code can now point new
loader_info fields to the firmware's command line, rather than having
to do early manipulation of the /chosen bootargs property which may
then be rewritten again by the core.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] Add device tree utility functions to zImage

This patch adds a library of useful device tree manipulation functions
to the zImage library, for use by platform code. These functions are
based on the hooks already in dt_ops, so they're not dependent on a
particular device tree implementation. This patch also slightly
streamlines the code in main.c using these new functions.

This is a consolidation of my work in this area with Scott Wood's
patches to a very similar end.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] New reg.h for the zImage

This patch adds a reg.h to the zImage code, with common definitions
for accessing system registers. For now, this includes functions for
retrieving the PVR and the stack pointer. This patch then uses the
new reg.h to let start() display the running stack address without
having to explicitly pass the stack as a parameter from the asm code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] Add gcc format warnings to zImage printf()

This patch adds the correct attributes to the zImage's versions of
printf to make gcc generate format string mismatch warnings. It also
corrects several minor problems with format strings in the zImage thus
discovered.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] bootwrapper: Add a fatal error helper

Add a macro fatal that calls printf then exit. User must include stdio.h.

Typically replaces 3 lines with 1, although I added back some whitespace.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] boot: export flush_cache

Move the declaration of flush_cache to ops.h for use by platform code.

Signed-off-by: Milton Miller <miltonm@bga.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] zImage: Cleanup and improve zImage entry point

This patch re-organises the way the zImage wrapper code is entered, to
allow more flexibility on platforms with unusual entry conditions.
After this patch, a platform .o file has two options:

1) It can define a _zimage_start, in which case the platform code gets
control from the very beginning of execution. In this case the
platform code is responsible for relocating the zImage if necessary,
clearing the BSS, performing any platform specific initialization, and
finally calling start() to load and enter the kernel.

2) It can define platform_init(). In this case the generic crt0.S
handles initial entry, and calls platform_init() before calling
start(). The signature of platform_init() is changed, however, to
take up to 5 parameters (in r3..r7) as they come from the platform's
initial loader, instead of a fixed set of parameters based on OF's
usage.

When using the generic crt0.S, the platform .o can optionally
supply a custom stack to use, using the BSS_STACK() macro. If this
is not supplied, the crt0.S will assume that the loader has
supplied a usable stack.

In either case, the platform code communicates information to the
generic code (specifically, a PROM pointer for OF systems, and/or an
initrd image address supplied by the bootloader) via a global
structure "loader_info".

In addition the wrapper script is rearranged to ensure that the
platform .o is always linked first. This means that platforms where
the zImage entry point is at a fixed address or offset, rather than
being encoded in the binary header can be supported using option (1).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] zImage: Cleanup and improve prep_kernel()

This patch rewrites prep_kernel() in the zImage wrapper code to be
clearer and more flexible. Notable changes:

- Handling of the initrd image from prep_kernel() has moved
into a new prep_initrd() function.
- The address of the initrd image is now added as device tree
properties, as the kernel expects.
- We only copy a packaged initrd image to a new location if it
is in danger of being clobbered when the kernel moves to its final
location, instead of always.
- By default we decompress the kernel directly to address 0,
instead of requiring it to relocate itself. Platforms (such as OF)
where doing this could clobber still-live firmware data structures can
override the vmlinux_alloc hook to provide an alternate place to
decompress the kernel.
- We no longer pass lots of information between functions in
global variables.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] zImage: Add more flexible gunzip convenience functions

At present, arch/powerpc/boot/main.c includes a gunzip() function
which is a convenient wrapper around zlib. However, it doesn't
conveniently allow decompressing part of an image to one location,
then the remainder to a different address.

This patch adds a new set of more flexible convenience wrappers around
zlib, moving them to their own file, gunzip_util.c, in the process.
These wrappers allow decompressing sections of the compressed image to
different locations. In addition, they transparently handle
uncompressed data, avoiding special case code to handle uncompressed
vmlinux images.

The patch also converts main.c to use the new wrappers, using the new
flexibility to avoid decompressing the vmlinux's ELF header twice as
we did previously. That in turn means we avoid extending our
allocations for the vmlinux to allow space for the extra copy of the
ELF header.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] Cleanup zImage handling of kernel entry with flat device tree

This makes 2 changes to clean up the flat device tree handling
logic in the zImage wrapper.

First, there were two callbacks from the dt_ops structure used for
producing a final flat tree to pass to the kerne: dt_ops.ft_pack()
which packed the flat tree (possibly a no-op) and dt_ops.ft_addr()
which retreived the address of the final blob. Since they were only
ever called together, this patch combines the two into a single new
callback, dt_ops.finalize(). This new callback does whatever
platform-dependent things are necessary to produce a final flat device
tree blob, and returns the blob's addres.

Second, the current logic calls the kernel with a flat device tree if
one is build into the zImage wrapper, otherwise it boots the kernel
with a PROM pointer, expecting the kernel to copy the OF device tree
itself. This approach precludes the possibility of the platform
wrapper code building a flat device tree from whatever
platform-specific information firmware provides. Thus, this patch
takes the more sensible approach of invoking the kernel with a flat
tree if the dt_ops.finalize callback provides one (by whatever means).

So, the dt_ops.finalize callback can be NULL, or can be a function
which returns NULL. In either case, the zImage wrapper logic assumes
that this is a platform with OF and invokes the kernel accordingly.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] Small clarification of initrd handling

This patch makes the handling of the initrd (or initramfs) in the
zImage wrapper a little easier to follow. Instead of passing the
initrd addresses out from prep_kernel() via the cryptic a1 and a2
parameters, use the global struct add_range, 'initrd'. prep_kernel()
already passes information through the 'vmlinux' addr_range struct, so
this seems like a reasonable extension.

Some comments also clarify the logic with prep_kernel(): we use an
initrd included in the zImage if present, otherwise we use an initrd
passed in by the bootloader in the a1 and a2 parameters (yaboot, at
least, uses this mechanism to pass an initrd).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] More bootwrapper reorganization

More reorganization of the bootwrapper:
- Add dtb section to zImage
- ft_init now called by platform_init
- Pack a flat dt before calling kernel
- Remove size parameter from free
- printf only calls console_ops.write it its not NULL
- Some cleanup

Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] Start arch/powerpc/boot code reorganization

This abstracts the operations used in the bootwrapper, and defines
the operations needed for the bootwrapper to run on an OF platform.

The operations have been divided up into platform ops (platform_ops),
firmware ops (fw_ops), device tree ops (dt_ops), and console ops
(console_ops).

The proper operations will be hooked up at runtime to provide the
functionality that you need.

Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[POWERPC] Editable kernel command-line in zImage binary.

zImage will set /chosen/bootargs (if it is otherwise empty) with the
contents of a buffer in the section "__builtin_cmdline". This permits
tools to edit zImage binaries to set the command-line eventually
processed by vmlinux.

--
Signed-off-by: Michal Ostrowski <mostrows@watson.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

[PATCH] powerpc: remove check for ELF offset in powerpc bootimage

Do not check for offset, it is always set.

Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>

powerpc: Make COFF zImages for old 32-bit powermacs

This adds code to build zImage.coff and/or zImage.initrd.coff when
CONFIG_PPC32 and CONFIG_PPC_PMAC are defined. It also restructures
the OF client code and adds some workarounds for OF quirks on the
older machines.

Signed-off-by: Paul Mackerras <paulus@samba.org>

powerpc: Move ppc64 boot wrapper code over to arch/powerpc

This also extends the code to handle 32-bit ELF vmlinux files as well
as 64-bit ones. This is sufficient for booting on new-world 32-bit
powermacs (i.e. all recent machines).

Signed-off-by: Paul Mackerras <paulus@samba.org>