Commit 65987a8553061515b5851b472081aedb9837a391 upstream.

Split out the lookup of the processor type and associated error handling
from the rest of setup_processor() - we will need to use this in the
secondary CPU bringup path for big.Little Spectre variant 2 mitigation.
Reviewed-by: NJulien Thierry <julien.thierry@arm.com>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NDavid A. Long <dave.long@linaro.org>
Reviewed-by: NJulien Thierry <julien.thierry@arm.com>
Tested-by: NJulien Thierry <julien.thierry@arm.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>

Converts the ARM interrupt code to use the recently added
GENERIC_IRQ_MULTI_HANDLER, which is essentially just a copy of ARM's
existhing MULTI_IRQ_HANDLER.  The only changes are:

* handle_arch_irq is now defined in a generic C file instead of an
  arm-specific assembly file.
 
* handle_arch_irq is now marked as __ro_after_init.
Signed-off-by: NPalmer Dabbelt <palmer@sifive.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: linux@armlinux.org.uk
Cc: catalin.marinas@arm.com
Cc: Will Deacon <will.deacon@arm.com>
Cc: jonas@southpole.se
Cc: stefan.kristiansson@saunalahti.fi
Cc: shorne@gmail.com
Cc: jason@lakedaemon.net
Cc: marc.zyngier@arm.com
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: nicolas.pitre@linaro.org
Cc: vladimir.murzin@arm.com
Cc: keescook@chromium.org
Cc: jinb.park7@gmail.com
Cc: yamada.masahiro@socionext.com
Cc: alexandre.belloni@bootlin.com
Cc: pombredanne@nexb.com
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: kstewart@linuxfoundation.org
Cc: jhogan@kernel.org
Cc: mark.rutland@arm.com
Cc: ard.biesheuvel@linaro.org
Cc: james.morse@arm.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: openrisc@lists.librecores.org
Link: https://lkml.kernel.org/r/20180622170126.6308-3-palmer@sifive.com

Instead select the PHYS_ADDR_T_64BIT for 32-bit architectures that need a
64-bit phys_addr_t type directly.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NJames Hogan <jhogan@kernel.org>

With a kernel containing both DT and atag support, the diagnostics
output when the dtb is missing or corrupt assume that we're trying
to boot using atags and the machine ID, and only print the machine
ID.  This is not useful for diagnosing a missing or corrupt dtb.

Move the message into arch/arm/kernel/setup.c, and print the address
of the dtb/atag list, and the first 16 bytes of memory of the dtb or
atag list.

This allows us to see whether the dtb was corrupted in some way,
causing the fallback to the machine ID / atag list.
Tested-by: NKeerthy <j-keerthy@ti.com>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>

Allocating the crashkernel region outside lowmem causes the kernel to
oops while trying to kexec into the new kernel:

Loading crashdump kernel...
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = edd70000
[00000000] *pgd=de19e835
Internal error: Oops: 817 [#2] SMP ARM
Modules linked in: ...
CPU: 0 PID: 689 Comm: sh Not tainted 4.12.0-rc3-next-20170601-04015-gc3a5a20
Hardware name: Generic DRA74X (Flattened Device Tree)
task: edb32f00 task.stack: edf18000
PC is at memcpy+0x50/0x330
LR is at 0xe3c34001
pc : [<c04baf30>]    lr : [<e3c34001>]    psr: 800c0193
sp : edf19c2c  ip : 0a000001  fp : c0553170
r10: c055316e  r9 : 00000001  r8 : e3130001
r7 : e4903004  r6 : 0a000014  r5 : e3500000  r4 : e59f106c
r3 : e59f0074  r2 : ffffffe8  r1 : c010fb88  r0 : 00000000
Flags: Nzcv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 10c5387d  Table: add7006a  DAC: 00000051
Process sh (pid: 689, stack limit = 0xedf18218)
Stack: (0xedf19c2c to 0xedf1a000)
...
[<c04baf30>] (memcpy) from [<c010fae0>] (machine_kexec+0xa8/0x12c)
[<c010fae0>] (machine_kexec) from [<c01e4104>] (__crash_kexec+0x5c/0x98)
[<c01e4104>] (__crash_kexec) from [<c01e419c>] (crash_kexec+0x5c/0x68)
[<c01e419c>] (crash_kexec) from [<c010c5c0>] (die+0x228/0x490)
[<c010c5c0>] (die) from [<c011e520>] (__do_kernel_fault.part.0+0x54/0x1e4)
[<c011e520>] (__do_kernel_fault.part.0) from [<c082412c>] (do_page_fault+0x1e8/0x400)
[<c082412c>] (do_page_fault) from [<c010135c>] (do_DataAbort+0x38/0xb8)
[<c010135c>] (do_DataAbort) from [<c0823584>] (__dabt_svc+0x64/0xa0)

This is caused by image->control_code_page being a highmem page, so
page_address(image->control_code_page) returns NULL.  In any case, we
don't want the control page to be a highmem page.

We already limit the crash kernel region to the top of 32-bit physical
memory space.  Also limit it to the top of lowmem in physical space.
Reported-by: NKeerthy <j-keerthy@ti.com>
Tested-by: NKeerthy <j-keerthy@ti.com>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>

Cache support is optional feature in M-class cores, thus DminLine or
IminLine of Cache Type Register is zero if caches are not implemented,
but we check the whole CTR which has other features encoded there.
Let's be more precise and check for DminLine and IminLine of CTR
before we set cacheid.
Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>

To cope with the variety in ARM architectures and configurations, the
pagetable attributes for kernel memory are generated at runtime to match
the system the kernel finds itself on. This calculated value is stored
in pgprot_kernel.

However, when early fixmap support was added for ARM (commit
a5f4c561) the attributes used for mappings were hard coded because
pgprot_kernel is not set up early enough. Unfortunately, when fixmap is
used after early boot this means the memory being mapped can have
different attributes to existing mappings, potentially leading to
unpredictable behaviour. A specific problem also exists due to the hard
coded values not include the 'shareable' attribute which means on
systems where this matters (e.g. those with multiple CPU clusters) the
cache contents for a memory location can become inconsistent between
CPUs.

To resolve these issues we change fixmap to use the same memory
attributes (from pgprot_kernel) that the rest of the kernel uses. To
enable this we need to refactor the initialisation code so
build_mem_type_table() is called early enough. Note, that relies on early
param parsing for memory type overrides passed via the kernel command
line, so we need to make sure this call is still after
parse_early_params().

[ardb: keep early_fixmap_init() before param parsing, for earlycon]

Fixes: a5f4c561 ("ARM: 8415/1: early fixmap support for earlycon")
Cc: <stable@vger.kernel.org> # v4.3+
Tested-by: Nafzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: NJon Medhurst <tixy@linaro.org>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>

adjust_lowmem_bounds is responsible for setting up the boundary for
lowmem/highmem. This needs to be setup before memblock reservations can
occur. At the time memblock reservations can occur, memory can also be
removed from the system. The lowmem/highmem boundary and end of memory
may be affected by this but it is currently not recalculated. On some
systems this may be harmless, on others this may result in incorrect
ranges being passed to the main memory allocator. Correct this by
recalculating the lowmem/highmem boundary after all reservations have
been made.
Tested-by: NMagnus Lilja <lilja.magnus@gmail.com>
Signed-off-by: NLaura Abbott <labbott@redhat.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The logic for sanity_check_meminfo has become difficult to
follow. Clean up the code so it's more obvious what the code
is actually trying to do. Additionally, meminfo is now removed
so rename the function to better describe its purpose.
Tested-by: NMagnus Lilja <lilja.magnus@gmail.com>
Reviewed-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NLaura Abbott <lauraa@codeaurora.org>
Signed-off-by: NLaura Abbott <labbott@redhat.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

With the addition of caches to the V7M Architecture a new Cache Type
Register (CTR) is defined at 0xE000ED7C. This register serves the same
purpose as the V7A/R version and accessed via the read_cpuid_cachetype.
Signed-off-by: NJonathan Austin <jonathan.austin@arm.com>
Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
Tested-by: NAndras Szemzo <sza@esh.hu>
Tested-by: NJoachim Eastwood <manabian@gmail.com>
Tested-by: NAlexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Currently we use raw cp15 operations to access the cache setup data.

This patch abstracts the CSSELR and CCSIDR accessors out to a header so
that the implementation for them can be switched out as we do with other
cpu/cachetype operations.
Signed-off-by: NJonathan Austin <jonathan.austin@arm.com>
Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
Tested-by: NAndras Szemzo <sza@esh.hu>
Tested-by: NJoachim Eastwood <manabian@gmail.com>
Tested-by: NAlexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Guided by grsecurity's analogous __read_only markings in arch/arm,
this applies several uses of __ro_after_init to structures that are
only updated during __init.
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Advertise the location of bootable RAM to kexec-tools.  kexec needs to
know where it can place the kernel in RAM, and so be executable when the
system needs to jump into it.

Advertise these areas in /proc/iomem with a "System RAM (boot alias)"
tag.

Link: http://lkml.kernel.org/r/E1b8ko4-0004HA-GF@rmk-PC.armlinux.org.ukSigned-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPratyush Anand <panand@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Vitaly Andrianov <vitalya@ti.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Simon Horman <horms@verge.net.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Advertise a resource which describes where the crash kernel is located
in the boot view of RAM.  This allows kexec-tools to have this vital
information.

Link: http://lkml.kernel.org/r/E1b8knz-0004H4-Bd@rmk-PC.armlinux.org.ukSigned-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Cc: Baoquan He <bhe@redhat.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Pratyush Anand <panand@redhat.com>
Cc: Vitaly Andrianov <vitalya@ti.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Simon Horman <horms@verge.net.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move xen_early_init() before efi_init(), then when calling efi_init()
could initialize Xen specific UEFI.

Check if it runs on Xen hypervisor through the flat dts.

Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NJulien Grall <julien.grall@arm.com>
Tested-by: NJulien Grall <julien.grall@arm.com>
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>

The _etext position is defined to be the end of the kernel text code,
and should not include any part of the data segments. This interferes
with things that might check memory ranges and expect executable code
up to _etext. Just to be conservative, leave the kernel resource as
it was, using __init_begin instead of _etext as the end mark.
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

After patch "of/platform: Add common method to populate default bus",
it is possible for arch code to remove unnecessary callers of
of_platform_populate with default match table.
Acked-by: NViresh Kumar <viresh.kumar@linaro.org>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Lee Jones <lee@kernel.org>
Cc: Krzysztof Halasa <khalasa@piap.pl>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Santosh Shilimkar <ssantosh@kernel.org>
Cc: Roland Stigge <stigge@antcom.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Viresh Kumar <vireshk@kernel.org>
Cc: Shiraz Hashim <shiraz.linux.kernel@gmail.com>
Cc: Tony Prisk <linux@prisktech.co.nz>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NRob Herring <robh@kernel.org>

The of_iommu_init() is called multiple times by arch code,
make it postcore_initcall_sync, then we can drop relevant
calls fully.

Note, the IOMMUs should have a chance to perform some basic
initialisation before we start adding masters to them. So
postcore_initcall_sync is good choice, it ensures of_iommu_init()
called before of_platform_populate.
Acked-by: NRich Felker <dalias@libc.org>
Tested-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: NJoerg Roedel <jroedel@suse.de>
Signed-off-by: NRob Herring <robh@kernel.org>

The real limit is the top of the visible physical address space with
the MMU turned off.  Hence, we need to limit the crash kernel allocation
running-view physical address of the top of the boot-view physical
address space.
Reviewed-by: NPratyush Anand <panand@redhat.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When the kernel crashkernel parameter is specified with just a size, we
are supposed to allocate a region from RAM to store the crashkernel.
However, ARM merely reserves physical address zero with no checking that
there is even RAM there.

Fix this by lifting similar code from x86, importing it to ARM with the
ARM specific parameters added.  In the absence of any platform specific
information, we allocate the crashkernel region from the first 512MB of
physical memory.

Update the kdump documentation to reflect this change.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NPratyush Anand <panand@redhat.com>

In order to hand over the framebuffer described by the GOP protocol and
discovered by the UEFI stub, make struct screen_info accessible by the
stub. This involves allocating a loader data buffer and passing it to the
kernel proper via a UEFI Configuration Table, since the UEFI stub executes
in the context of the decompressor, and cannot access the kernel's copy of
struct screen_info directly.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-22-git-send-email-matt@codeblueprint.co.ukSigned-off-by: NIngo Molnar <mingo@kernel.org>

Commit b8c9592b "ARM: 8318/1: treat CPU feature register fields as signed
quantities" accidentally altered cpuid register used to demote
HWCAP_SWP.
ARM ARM says that SyncPrim_instrs bits in ID_ISAR3 should be used with
SynchPrim_instrs_frac from ID_ISAR4. So, follow this rule.
Signed-off-by: NVladimir Murzin <vladimir.murzin@arm.com>
Acked-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

It was reported that a kernel with CONFIG_ARM_PATCH_IDIV=y stopped
booting when compiled with the upcoming gcc 6.  Turns out that turning
a function address into a writable array is undefined and gcc 6 decided
it was OK to omit the store to the first word of the function while
still preserving the store to the second word.

Even though gcc 6 is now fixed to behave more coherently, it is a
mystery that gcc 4 and gcc 5 actually produce wanted code in the kernel.
And in fact the reduced test case to illustrate the issue does indeed
break with gcc < 6 as well.

In any case, let's guard the kernel against undefined compiler behavior
by hiding the nature of the array location as suggested by gcc
developers.

Reference: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70128Signed-off-by: NNicolas Pitre <nico@linaro.org>
Reported-by: NMarcin Juszkiewicz <mjuszkiewicz@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org # v4.5
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Set IORESOURCE_SYSTEM_RAM in flags of resource ranges with
"System RAM", "Kernel code", "Kernel data", and "Kernel bss".

Note that:

 - IORESOURCE_SYSRAM (i.e. modifier bit) is set in flags when
   IORESOURCE_MEM is already set. IORESOURCE_SYSTEM_RAM is defined
   as (IORESOURCE_MEM|IORESOURCE_SYSRAM).

 - Some archs do not set 'flags' for children nodes, such as
   "Kernel code".  This patch does not change 'flags' in this
   case.
Signed-off-by: NToshi Kani <toshi.kani@hpe.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@linux-mips.org
Cc: linux-mm <linux-mm@kvack.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1453841853-11383-7-git-send-email-bp@alien8.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

The ARM compiler inserts calls to __aeabi_idiv() and
__aeabi_uidiv() when it needs to perform division on signed and
unsigned integers. If a processor has support for the sdiv and
udiv instructions, the kernel may overwrite the beginning of those
functions with those instructions and a "bx lr" to get better
performance.

To ensure that those functions are aligned to a 32-bit word for easier
patching (which might not always be the case in Thumb mode) and that
the two patched instructions end up in the same cache line, a 8-byte
alignment is enforced when ARM_PATCH_IDIV is selected.

This was heavily inspired by a previous patch from Stephen Boyd.
Signed-off-by: NNicolas Pitre <nico@linaro.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This adds support to the kernel proper for booting via UEFI. It shares
most of the code with arm64, so this patch mostly just wires it up for
use with ARM.

Note that this does not include the EFI stub, it is added in a subsequent
patch.
Tested-by: NRyan Harkin <ryan.harkin@linaro.org>
Reviewed-by: NMatt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>

This enables the generic early_ioremap implementation for ARM.

It uses the fixmap region reserved for kmap. Since early_ioremap
is only supported before paging_init(), and kmap is only supported
afterwards, this is guaranteed not to cause any clashes.
Tested-by: NRyan Harkin <ryan.harkin@linaro.org>
Reviewed-by: NMatt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>

Add early fixmap support, initially to support permanent, fixed
mapping support for early console. A temporary, early pte is
created which is migrated to a permanent mapping in paging_init.
This is also needed since the attributes may change as the memory
types are initialized. The 3MiB range of fixmap spans two pte
tables, but currently only one pte is created for early fixmap
support.

Re-add FIX_KMAP_BEGIN to the index calculation in highmem.c since
the index for kmap does not start at zero anymore. This reverts
4221e2e6 ("ARM: 8031/1: fixmap: remove FIX_KMAP_BEGIN and
FIX_KMAP_END") to some extent.

Cc: Mark Salter <msalter@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NStefan Agner <stefan@agner.ch>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Now that the common PSCI client code has been factored out to
drivers/firmware, and made safe for 32-bit use, move the 32-bit ARM code
over to it. This results in a moderate reduction of duplicated lines,
and will prevent further duplication as the PSCI client code is updated
for PSCI 1.0 and beyond.

The two legacy platform users of the PSCI invocation code are updated to
account for interface changes. In both cases the power state parameter
(which is constant) is now generated using macros, so that the
pack/unpack logic can be killed in preparation for PSCI 1.0 power state
changes.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Acked-by: NRob Herring <robh@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Writes to /sys/.../cpuX/online fail if we determine the platform
doesn't support hotplug for that CPU. Furthermore, if the cpu_die
op isn't specified the system hangs when we try to offline a CPU
and it comes right back online unexpectedly. Let's figure this
stuff out before we make the sysfs nodes so that the online file
doesn't even exist if it isn't (at least sometimes) possible to
hotplug the CPU.

Add a new 'cpu_can_disable' op and repoint all 'cpu_disable'
implementations at it because all implementers use the op to
indicate if a CPU can be hotplugged or not in a static fashion.
With PSCI we may need to add a 'cpu_disable' op so that the
secure OS can be migrated off the CPU we're trying to hotplug.
In this case, the 'cpu_can_disable' op will indicate that all
CPUs are hotpluggable by returning true, but the 'cpu_disable' op
will make a PSCI migration call and occasionally fail, denying
the hotplug of a CPU. This shouldn't be any worse than x86 where
we may indicate that all CPUs are hotpluggable but occasionally
we can't offline a CPU due to check_irq_vectors_for_cpu_disable()
failing to find a CPU to move vectors to.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Dave Martin <Dave.Martin@arm.com>
Acked-by: Simon Horman <horms@verge.net.au> [shmobile portion]
Tested-by: NSimon Horman <horms@verge.net.au>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: <linux-sh@vger.kernel.org>
Tested-by: NTyler Baker <tyler.baker@linaro.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Eliminate the needless nommu version of this function, and get rid of
the proc_info_list structure argument - we no longer need this in order
to fix up the page table entries.
Acked-by: NSantosh Shilimkar <ssantosh@kernel.org>
Tested-by: NMurali Karicheri <m-karicheri2@ti.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Currently, Xen is initialized/discovered in an initcall. This doesn't
allow us to support earlyprintk or choosing the preferred console when
running on Xen.

The current function xen_guest_init is now split in 2 parts:
    - xen_early_init: Check if there is a Xen node in the device tree
    and setup domain type
    - xen_guest_init: Retrieve the information from the device node and
    initialize Xen (grant table, shared page...)

The former is called in setup_arch, while the latter is an initcall.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NJulien Grall <julien.grall@linaro.org>
Acked-by: NIan Campbell <ian.campbell@citrix.com>
Acked-by: NWill Deacon <will.deacon@arm.com>

This grabs the serial number shown in cpuinfo from the serial-number device-tree
property in priority. When booting with ATAGs (and without device-tree), the
provided number is still shown instead.
Signed-off-by: NPaul Kocialkowski <contact@paulk.fr>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When running the 32-bit ARM kernel on ARMv8 capable bare metal (e.g.,
32-bit Android userland and kernel on a Cortex-A53), or as a KVM guest
on a 64-bit host, we should advertise the availability of the Crypto
instructions, so that userland libraries such as OpenSSL may use them.
(Support for the v8 Crypto instructions in the 32-bit build was added
to OpenSSL more than six months ago)

This adds the ID feature bit detection, and sets elf_hwcap2 accordingly.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The various CPU feature registers consist of 4-bit blocks that
represent signed quantities, whose positive values represent
incremental features, and whose negative values are reserved.

To improve forward compatibility, update the feature detection
code to take possible future higher values into account, but
ignore negative values.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Replace inline asm statement in __get_cpu_architecture() with equivalent
macro invocation, i.e. read_cpuid_ext(CPUID_EXT_MMFR0);

As an added bonus, this squashes a potential bug, described by Paul
Walmsley in commit 067e710b ("ARM: 7801/1: prevent gcc 4.5 from
reordering extended CP15 reads above is_smp() test").
Signed-off-by: NMarc Gonzalez <marc_gonzalez@sigmadesigns.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The current rounding of "size" is wrong:

 - If "start" is sufficiently near the next page boundary, "size"
   is decremented by more than enough and the last page is lost.

 - If "size" is sufficiently small, it is wrapped around and gets
   a bogus value.
Signed-off-by: NMasahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Commit 9fc2105a ("ARM: 7830/1: delay: don't bother reporting
bogomips in /proc/cpuinfo") breaks audio in python, and probably
elsewhere, with message

  FATAL: cannot locate cpu MHz in /proc/cpuinfo

I'm not the first one to hit it, see for example

  https://theredblacktree.wordpress.com/2014/08/10/fatal-cannot-locate-cpu-mhz-in-proccpuinfo/
  https://devtalk.nvidia.com/default/topic/765800/workaround-for-fatal-cannot-locate-cpu-mhz-in-proc-cpuinf/?offset=1

Reading original changelog, I have to say "Stop breaking working setups.
You know who you are!".
Signed-off-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We need to ensure that the IOMMUs in the system have a chance to perform
some basic initialisation before we start adding masters to them.

This patch adds a call to of_iommu_init before of_platform_populate.
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

The generic dump_stack() code provides the facility to include the
machine name in the stack dump, which can be useful information.  Add
a call to dump_stack_set_arch_desc() for the generic code to print
this information.
Tested-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>