During the HCI init phase a completed request might be the last part of
the setup procedure after which the actual init procedure starts. The
init procedure begins with a call to hci_reset_req() which sets the
HCI_RESET flag. The purpose of this flag is to make us ignore any
updates to ncmd/cmd_cnt as long as we haven't received the command
complete event for the HCI_Reset. There's a potential race with this
however:
hci_req_cmd_complete(hdev, opcode, status);
if (ev->ncmd && !test_bit(HCI_RESET, &hdev->flags)) {
atomic_set(&hdev->cmd_cnt, 1);
if (!skb_queue_empty(&hdev->cmd_q))
queue_work(hdev->workqueue, &hdev->cmd_work);
}
Since the hci_req_cmd_complete() will trigger the completion of the
setup stage, it's possible that hci_reset_req() gets called before we
try to read ev->ncmd and the HCI_RESET flag. Because of this the cmd_cnt
would never be updated and the hci_reset_req() in practice ends up
blocking itself.
This patch fixes the issue by updating cmd_cnt before notifying the
request completion, and then reading it again to determine whether the
cmd_work should be queued or not.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Pull x86 fix from Ingo Molnar:
"Fix x86 syscall exit code bug that resulted in spurious non-execution
of TIF-driven user-return worklets, causing big trouble for things
like KVM that rely on user notifiers for correctness of their vcpu
model, causing crashes like double faults"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/asm/entry: Check for syscall exit work with IRQs disabled
Pull scheduler fix from Ingo Molnar:
"A single sched/rt corner case fix for RLIMIT_RTIME correctness"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix RLIMIT_RTTIME when PI-boosting to RT
Pull perf fix from Ingo Molnar:
"A perf kernel side fix for a fuzzer triggered lockup"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Fix irq_work 'tail' recursion
Pull locking fix from Ingo Molnar:
"A module unload lockdep race fix"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
lockdep: Fix the module unload key range freeing logic
Pull parsic fixes from Helge Deller:
"One patch from Mikulas fixes a bug on parisc by artifically
incrementing the counter in pmd_free when the kernel tries to free
the preallocated pmd.
Other than that we now prevent that syscalls gets added without
incrementing __NR_Linux_syscalls and fix the initial pmd setup code
if a default page size greater than 4k has been selected"
* 'parisc-4.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix pmd code to depend on PT_NLEVELS value, not on CONFIG_64BIT
parisc: mm: don't count preallocated pmds
parisc: Add compile-time check when adding new syscalls
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Merge tag 'arc-4.0-fixes-part-2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC fixes from Vineet Gupta:
"We found some issues with signal handling taking down the system. I
know its late, but these are important and all marked for stable.
ARC signal handling related fixes uncovered during recent testing of
NPTL tools"
* tag 'arc-4.0-fixes-part-2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: signal handling robustify
ARC: SA_SIGINFO ucontext regs off-by-one
Pull selinux bugfix from James Morris.
Fix broken return value.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
selinux: fix sel_write_enforce broken return value
When the patch for e16343c47e (ARM: 8160/1: drop warning about
return_address not using unwind tables) was created there was still more
code in said branch. Probably this simplification was just missed during
conflict resolution when the patch was applied.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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>
Usually ELF_ET_DYN_BASE is 2/3 of TASK_SIZE. With 3G/1G user/kernel
split this is not so, because 2*TASK_SIZE overflows 32 bits,
so the actual value of ELF_ET_DYN_BASE is:
(2 * TASK_SIZE / 3) = 0x2a000000
When ASLR is disabled PIE binaries will load at ELF_ET_DYN_BASE address.
On 32bit platforms AddressSanitzer uses addresses [0x20000000 - 0x40000000]
for shadow memory [1]. So ASan doesn't work for PIE binaries when ASLR disabled
as it fails to map shadow memory.
Also after Kees's 'split ET_DYN ASLR from mmap ASLR' patchset PIE binaries
has a high chance of loading somewhere in between [0x2a000000 - 0x40000000]
even if ASLR enabled. This makes ASan with PIE absolutely incompatible.
Fix overflow by dividing TASK_SIZE prior to multiplying.
After this patch ELF_ET_DYN_BASE equals to (for CONFIG_VMSPLIT_3G=y):
(TASK_SIZE / 3 * 2) = 0x7f555554
[1] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerAlgorithm#Mapping
Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Reported-by: Maria Guseva <m.guseva@samsung.com>
Cc: stable@vger.kernel.org
Signed-off-by: Russell 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: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell 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: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This moves the .idmap.text section closer to .head.text, so that
relative branches are less likely to go out of range if the kernel
text gets bigger.
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch replaces the 'branch to setup()' instructions embedded
in the PROCINFO structs with the offset to that setup function
relative to the base of the struct. This preserves the position
independent nature of that field, but uses a data item rather
than an instruction.
This is mainly done to prevent linker failures on large kernels,
where the setup function is out of reach for the branch.
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch uses iio_trigger_get to increment the reference
count of trigger device, to avoid incorrect assignment.
Can result in a null pointer dereference during removal if the
trigger has been changed before removal.
This patch refers to a similar situation encountered through the
following discussion:
http://www.spinics.net/lists/linux-iio/msg13669.html
Signed-off-by: Darshana Padmadas <darshanapadmadas@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Depending on conversion mode used, the ADC clock (ADCK) needs
to be below a maximum frequency. According to Vybrid's data
sheet this is 20MHz for the low power conversion mode.
The ADC clock is depending on input clock, which is the bus
clock by default. Vybrid SoC are typically clocked at at 400MHz
or 500MHz, which leads to 66MHz or 83MHz bus clock respectively.
Hence, a divider of 8 is required to stay below the specified
maximum clock of 20MHz.
Due to the different bus clock speeds, the resulting sampling
frequency is not static. Hence use the ADC clock and calculate
the actual available sampling frequency dynamically.
This fixes bogous values observed on some 500MHz clocked Vybrid
SoC. The resulting value usually showed Bit 9 being stuck at 1,
or 0, which lead to a value of +/-512.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Acked-by: Fugang Duan <B38611@freescale.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Fixes:
drivers/built-in.o: In function `cc10001_adc_probe':
cc10001_adc.c:(.text+0x412e92): undefined reference to `devm_ioremap_resource'
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
It can be used exactly like L3GD20 but it has a different WhoAmI
register value.
Signed-off-by: Robert Dolca <robert.dolca@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This adds a test of the switch_endian() syscall we added in the previous
commit.
We test it by calling the endian switch syscall, and then executing some
code in the other endian to check everything went as expected. That code
checks registers we expect to be maintained are. If the endian switch
failed to happen that code sequence will be illegal and cause the test
to abort.
We then switch back to the original endian, do the same checks and
finally write a success message and exit(0).
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We currently have a "special" syscall for switching endianness. This is
syscall number 0x1ebe, which is handled explicitly in the 64-bit syscall
exception entry.
That has a few problems, firstly the syscall number is outside of the
usual range, which confuses various tools. For example strace doesn't
recognise the syscall at all.
Secondly it's handled explicitly as a special case in the syscall
exception entry, which is complicated enough without it.
As a first step toward removing the special syscall, we need to add a
regular syscall that implements the same functionality.
The logic is simple, it simply toggles the MSR_LE bit in the userspace
MSR. This is the same as the special syscall, with the caveat that the
special syscall clobbers fewer registers.
This version clobbers r9-r12, XER, CTR, and CR0-1,5-7.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When using generic_buffer to read data, the scale is not properly
detected for scale shared by type. This is caused by a problem
with the generation of generic name out of the full name.
E.g.: for current->name in_accel_z, the extracted generic name
is "in" (when it should be "in_accel"). This is used in generic_buffer
to generate scale and offset paths (in_accel_scale).
Consider the in_ or out_ prefix when extracting the generic name
from the full name.
Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
Reviewed-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This patch adds ABI documentation entries for in_rot_offset.
At least one user for these is present that is the HID Sensors Driver.
Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
MAX520 and MAX521 are protocol-compatible with the already supported
chips, just have more channels.
Signed-off-by: Antonio Fiol <antonio@fiol.es>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This patchset adds ABI documentation for the following attributes:
in_illuminance_scale, used atleast once in al3320a staging/iio/light/
in_illuminance_calibscale, used atleast once in cm32181
in_illuminance_input, used in cm3232 at least once
in_illuminance_raw used atleast once in al3320a
in_illuminance_clear_raw and in_illuminance_ir_raw exposed by
gp2ap020a00f with modifiers IIO_MOD_LIGHT_CLEAR and
IIO_MOD_LIGHT_IR respectively.
Signed-off-by: Darshana Padmadas <darshanapadmadas@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This adds support for the LIS3LV02 accelerometer found in the
ST Microelectronics Nomadik board series.
Cc: devicetree@vger.kernel.org
Cc: Denis CIOCCA <denis.ciocca@st.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
For all modern Bluetooth USB devices from Broadcom it makes a lot more
sense to use USB_VENDOR_AND_INTERFACE_INFO instead of manually adding
USB_DEVICE for each one of them. There are already interface entries
for these vendors and so just remove the duplicate device entries.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
The "sdc" node is missing the ranges property, it needs to be treated
as having an empty one otherwise translation fails for its children.
Fixes 746c9e9f92, "of/base: Fix PowerPC address parsing hack"
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Stable <stable@vger.kernel.org> # v3.18+
Currently OF_DYNAMIC and OF_OVERLAY are not visible to the user, and are
selected automatically only when needed.
Allow them to be enabled manually to improve device tree unit test
coverage.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Introduce empty node and property flag accessors when CONFIG_OF is not
defined. This allows us to use them without ifdef'ing them in places
where it makes sense to do so.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
The "sdc" node is missing the ranges property, it needs to be treated
as having an empty one otherwise translation fails for its children.
Fixes 746c9e9f92, "of/base: Fix PowerPC address parsing hack"
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Stable <stable@vger.kernel.org> # v3.18+
During suspend/migration operation we must wait for the VASI state reported
by the hypervisor to become Suspending prior to making the ibm,suspend-me
RTAS call. Calling routines to rtas_ibm_supend_me() pass a vasi_state variable
that exposes the VASI state to the caller. This is unnecessary as the caller
only really cares about the following three conditions; if there is an error
we should bailout, success indicating we have suspended and woken back up so
proceed to device tree update, or we are not suspendable yet so try calling
rtas_ibm_suspend_me again shortly.
This patch removes the extraneous vasi_state variable and simply uses the
return code to communicate how to proceed. We either succeed, fail, or get
-EAGAIN in which case we sleep for a second before trying to call
rtas_ibm_suspend_me again. The behaviour of ppc_rtas() remains the same,
but migrate_store() now returns the propogated error code on failure.
Previously -1 was returned from migrate_store() in the failure case which
equates to -EPERM and was clearly wrong.
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Cc: Nathan Fontenont <nfont@linux.vnet.ibm.com>
Cc: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Since spidev is a detail of how Linux controls a device rather than a
description of the hardware in the system we should never have a node
described as "spidev" in DT, any SPI device could be a spidev so this
is just not a useful description.
In order to help prevent users from writing such device trees generate a
warning if spidev is instantiated as a DT node without an ID in the match
table.
Signed-off-by: Mark Brown <broonie@kernel.org>
If multiple regulator devices of the same type exist in a system,
the regulator driver assigns generic names for the regulators it
provides, and debugfs is enabled, the regulator subsystem attempts
to create multiple entries with the same name in the regulator debugfs
directory. This fails for all but the first regulator, resulting in
multiple "Failed to create debugfs directory" log entries.
To avoid the problem, prepend the debugfs directory name for a regulator
with its parent device name if available, but only if no explicit
regulator name was provided.
Cc: Alan Tull <atull@opensource.altera.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch supports DPCM based sampling rate convert on Renesas sound
driver. It assumes...
1. SRC is implemented as FE
2. BE dai_link supports .be_hw_params_fixup
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This patch removes useless debug message. especially some kind of
"probed" message will be printed from core.c if it has #define DEBUG
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
clk_prepare_enable()/clk_disable_unprepare() uses mutex inside,
in concretely clk_prepare()/clk_unprepare().And it uses __schedule().
Then, raw_spin_lock/unlock_irq() is called, and it breaks Renesas
sound driver's spin lock irq.
This patch separates thesse into clk_prepare()/clk_unprepare() and
clk_enable/clk_disable. And call clk_prepare()/clk_unprepare() from
probe/remove function. Special thanks to Das Biju.
Reported-by: Das Biju <biju.das@bp.renesas.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Current rsnd-dpcm-card is supporting DPCM FE/BE sound card.
This patch adds .be_hw_params_fixup and enabled sampling convert rate.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Renesas sound card has "sampling rate convert" feature which
should be implemented via DPCM.
But, sound card driver point of view, it is difficult to add
this DPCM feature on simple-card driver. Especially, DT binding
support is very difficult.
This patch implements DPCM feature on DT as Renesas specific sound card.
This new driver is copied from current simple-card driver.
Main difference between simple-card and this driver are...
1. removed unused feature from simple-card
2. removed driver named prefix from DT property
3. CPU will be FE, CODEC will be BE with snd-soc-dummy
4. it supports sampling rate convert via .be_hw_params_fixup
5. board specific routing is implemented in driver
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
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>
Allow users to enable the vdso in Kconfig; include the vdso in the
build if CONFIG_VDSO is enabled. Add 'vdso_install' target.
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Initialize the VDSO page list at boot, install the VDSO mapping at
exec time, and update the data page during timer ticks. This code is
not built if CONFIG_VDSO is not enabled.
Account for the VDSO length when randomizing the offset from the
stack. The [vdso] and [vvar] pages are placed immediately following
the sigpage with separate _install_special_mapping calls.
We want to "penalize" systems lacking the arch timer as little
as possible. Previous versions of this code installed the VDSO
unconditionally and unmodified, making it a measurably slower way for
glibc to invoke the real syscalls on such systems. E.g. calling
gettimeofday via glibc goes from ~560ns to ~630ns on i.MX6Q.
If we can indicate to glibc that the time-related APIs in the VDSO are
not accelerated, glibc can continue to invoke the syscalls directly
instead of dispatching through the VDSO only to fall back to the slow
path.
Thus, if the architected timer is unusable for whatever reason, patch
the VDSO at boot time so that symbol lookups for gettimeofday and
clock_gettime return NULL. (This is similar to what powerpc does and
borrows code from there.) This allows glibc to perform the syscall
directly instead of passing control to the VDSO, which minimizes the
penalty. In my measurements the time taken for a gettimeofday call
via glibc goes from ~560ns to ~580ns (again on i.MX6Q), and this is
solely due to adding a test and branch to glibc's gettimeofday syscall
wrapper.
An alternative to patching the VDSO at boot would be to not install
the VDSO at all when the arch timer isn't usable. Another alternative
is to include a separate "dummy" vdso.so without gettimeofday and
clock_gettime, which would be selected at boot time. Either of these
would get cumbersome if the VDSO were to gain support for an API such
as getcpu which is unrelated to arch timer support.
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Place VDSO-related user-space code in arch/arm/kernel/vdso/.
It is almost completely written in C with some assembly helpers to
load the data page address, sample the counter, and fall back to
system calls when necessary.
The VDSO can service gettimeofday and clock_gettime when
CONFIG_ARM_ARCH_TIMER is enabled and the architected timer is present
(and correctly configured). It reads the CP15-based virtual counter
to compute high-resolution timestamps.
Of particular note is that a post-processing step ("vdsomunge") is
necessary to produce a shared object which is architecturally allowed
to be used by both soft- and hard-float EABI programs.
The 2012 edition of the ARM ABI defines Tag_ABI_VFP_args = 3 "Code is
compatible with both the base and VFP variants; the user did not
permit non-variadic functions to pass FP parameters/results."
Unfortunately current toolchains do not support this tag, which is
ideally what we would use.
The best available option is to ensure that both EF_ARM_ABI_FLOAT_SOFT
and EF_ARM_ABI_FLOAT_HARD are unset in the ELF header's e_flags,
indicating that the shared object is "old" and should be accepted for
backward compatibility's sake. While binutils < 2.24 appear to
produce a vdso.so with both flags clear, 2.24 always sets
EF_ARM_ABI_FLOAT_SOFT, with no way to inhibit this behavior. So we
have to fix things up with a custom post-processing step.
In fact, the VDSO code in glibc does much less validation (including
checking these flags) than the code for handling conventional
file-backed shared libraries, so this is a bit moot unless glibc's
VDSO code becomes more strict.
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Define the layout of the data structure shared between kernel and
userspace.
Track the vdso address in the mm_context; needed for communicating
AT_SYSINFO_EHDR to the ELF loader.
Add declarations for arm_install_vdso; implementation is in a
following patch.
Define AT_SYSINFO_EHDR, and, if CONFIG_VDSO=y, report the vdso shared
object address via the ELF auxiliary vector.
Note - this adds the AT_SYSINFO_EHDR in a new user-visible header
asm/auxvec.h; this is consistent with other architectures.
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARM errata 798181 is applicable for OMAP5/DRA7 based devices. So enable
the same in the build.
DRA7xx is based on Cortex-A15 r2p2 revision.
ARM Errata extract and workaround information is as below.
On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
adequately shooting down all use of the old entries. The
ARM_ERRATA_798181 option enables the Linux kernel workaround
for this erratum which sends an IPI to the CPUs that are running
the same ASID as the one being invalidated.
Signed-off-by: Praneeth Bajjuri <praneeth@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
