Reported-by: NDmitrii Kolesnichenko <dmitrii@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

ARCv2 ISA_CONFIG and ARC700_BUILD build config registers are not
compatible. cpuinfo_arc had isa info placeholder which was mashup of bits
form both.

Untangle this by defining it off of ARCv2 ISA info and it is fine even
for ARC700 since former is a super set of latter (ARC700 buildonly has 2
bits for atomics and stack check).

At runtime, we treat ARCv2 ISA info as a generic placeholder but
populate it correctly depending on ARC700 or HS.

This paves way for adding more HS specific bits in isa info which was
colliding with the extra bits for arc700.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

The top-level Makefile sets the default of UTS_MACHINE to $(ARCH).

If ARCH and UTS_MACHINE match, arch/$(ARCH)/Makefile need not specify
UTS_MACHINE explicitly.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

With corresponding clk driver now merged upstream, switch to it.

 - core_clk now represent the PLL (vs. fixed clk before)
 - input_clk represent the clk signal src for PLL (basically xtal)
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Commit 92e5aae4 "kernel/watchdog: split up config options"
introduced SOFTLOCKUP_DETECTOR which selects LOCKUP_DETECTOR
instead of the latter to be selected itself.

We need to adjust our defconfigs accordingly.
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

DW sdio controller has external ciu clock divider controlled
via register in SDIO IP. It divides sdio_ref_clk
(which comes from CGU) by 16 for default. So default mmcclk
clock (which comes to sdk_in) is 25000000 Hz.

So fix wrong current value (50000000 Hz) to actual 25000000 Hz.

Note this is a preventive fix, in line with similar change for HSDK
where this was actually needed. see:
http://lists.infradead.org/pipermail/linux-snps-arc/2017-September/002924.htmlSigned-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

DW sdio controller has external ciu clock divider controlled via
register in SDIO IP. Due to its unexpected default value
(it should divide by 1 but it divides by 8)
SDIO IP uses wrong ciu clock and works unstable

So add temporary fix and change clock frequency from 100000000
to 12500000 Hz until we fix dw sdio driver itself.

Fixes SNPS STAR 9001204800
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

DW ethernet controller on AXS10x hangs sometimes after SW reset, so
add temporary quirk to reset DW ethernet controller IP core.
This quirk can be removed after axs10x reset driver
(see http://patchwork.ozlabs.org/patch/800273/)
or simple reset driver
(see https://patchwork.kernel.org/patch/9903375/)
will be available in upstream.
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Some architectures define the no-op macros/functions copy_segments,
release_segments and forget_segments. These are used nowhere in the
tree, so removed them.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Acked-by: Vineet Gupta <vgupta@synopsys.com>   [for arch/arc]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

GFP_TEMPORARY was introduced by commit e12ba74d ("Group short-lived
and reclaimable kernel allocations") along with __GFP_RECLAIMABLE.  It's
primary motivation was to allow users to tell that an allocation is
short lived and so the allocator can try to place such allocations close
together and prevent long term fragmentation.  As much as this sounds
like a reasonable semantic it becomes much less clear when to use the
highlevel GFP_TEMPORARY allocation flag.  How long is temporary? Can the
context holding that memory sleep? Can it take locks? It seems there is
no good answer for those questions.

The current implementation of GFP_TEMPORARY is basically GFP_KERNEL |
__GFP_RECLAIMABLE which in itself is tricky because basically none of
the existing caller provide a way to reclaim the allocated memory.  So
this is rather misleading and hard to evaluate for any benefits.

I have checked some random users and none of them has added the flag
with a specific justification.  I suspect most of them just copied from
other existing users and others just thought it might be a good idea to
use without any measuring.  This suggests that GFP_TEMPORARY just
motivates for cargo cult usage without any reasoning.

I believe that our gfp flags are quite complex already and especially
those with highlevel semantic should be clearly defined to prevent from
confusion and abuse.  Therefore I propose dropping GFP_TEMPORARY and
replace all existing users to simply use GFP_KERNEL.  Please note that
SLAB users with shrinkers will still get __GFP_RECLAIMABLE heuristic and
so they will be placed properly for memory fragmentation prevention.

I can see reasons we might want some gfp flag to reflect shorterm
allocations but I propose starting from a clear semantic definition and
only then add users with proper justification.

This was been brought up before LSF this year by Matthew [1] and it
turned out that GFP_TEMPORARY really doesn't have a clear semantic.  It
seems to be a heuristic without any measured advantage for most (if not
all) its current users.  The follow up discussion has revealed that
opinions on what might be temporary allocation differ a lot between
developers.  So rather than trying to tweak existing users into a
semantic which they haven't expected I propose to simply remove the flag
and start from scratch if we really need a semantic for short term
allocations.

[1] http://lkml.kernel.org/r/20170118054945.GD18349@bombadil.infradead.org

[akpm@linux-foundation.org: fix typo]
[akpm@linux-foundation.org: coding-style fixes]
[sfr@canb.auug.org.au: drm/i915: fix up]
  Link: http://lkml.kernel.org/r/20170816144703.378d4f4d@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170728091904.14627-1-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Acked-by: NMel Gorman <mgorman@suse.de>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Neil Brown <neilb@suse.de>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I recently came upon a scenario where I would get a double fault
machine check exception tiriggered by a kernel module.
However the ensuing crash stacktrace (ksym lookup) was not working
correctly.

Turns out that machine check auto-disables MMU while modules are allocated
in kernel vaddr spapce.

This patch re-enables the MMU before start printing the stacktrace
making stacktracing of modules work upon a fatal exception.

Cc: stable@kernel.org
Signed-off-by: NJose Abreu <joabreu@synopsys.com>
Reviewed-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: moved code into low level handler to avoid in 2 places]

Currently we pass a string argument to show_kernel_fault_diag() which
describes the reason for the fault. This is not being used so just
add a pr_info() which outputs the fault information.

With this change we get from:

|
| Path: /bin/busybox
| CPU: 0 PID: 92 Comm: modprobe Not tainted 4.12.0-rc6 #30
| task: 9a254780 task.stack: 9a212000
|
| [ECR   ]: 0x00200400 => Other Fatal Err
|

to:

|
| Unhandled Machine Check Exception
| Path: /bin/busybox
| CPU: 0 PID: 92 Comm: modprobe Not tainted 4.12.0-rc6 #37
| task: 9a240780 task.stack: 9a226000
|
|[ECR   ]: 0x00200400 => Machine Check (Other Fatal Err)
|

Which can help debugging.

Cc: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NJose Abreu <joabreu@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This initial port adds support of ARC HS Development Kit board with some
basic features such serial port, USB, SD/MMC and Ethernet.

Essentially we run Linux kernel on all 4 cores (i.e. utilize SMP) and
heavily use IO Coherency for speeding-up DMA-aware peripherals.

Note as opposed to other ARC boards we link Linux kernel to
0x9000_0000 intentionally because cores 1 and 3 configured with DCCM
situated at our more usual link base 0x8000_0000. We still can use
memory region starting at 0x8000_0000 as we reallocate DCCM in our
platform code.

Note that PAE remapping for DMA clients does not work due to an RTL bug,
so CREG_PAE register must be programmed to all zeroes, otherwise it will
cause problems with DMA to/from peripherals even if PAE40 is not used.
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

	[Needed for HSDK]

Currently the first page of system (hence RAM base) is assumed to be
@ CONFIG_LINUX_LINK_BASE, where kernel itself is linked.

However is case of HSDK platform, for reasons explained in that patch,
this is not true. kernel needs to be linked @ 0x9000_0000 while DDR
is still wired at 0x8000_0000. To properly account for this 256M of RAM,
we need to introduce a new option and base page frame accountiing off of
it.
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: renamed  CONFIG_KERNEL_RAM_BASE_ADDRESS => CONFIG_LINUX_RAM_BASE
       : simplified changelog]

	[Needed for HSDK]

 - Currently IOC base is hardcoded to 0x8000_0000 which is default value
   of LINUX_LINK_BASE, but may not always be the case

 - IOC programming model imposes the constraint that IOC aperture size
   needs to be aligned to IOC base address, which we were not checking
   so far.
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: reworked the changelog]

with clk frequency setting code gone by prev commits, we can elide the
unconditonal DT parsing to the specific case of quad core config where
we possibly need to fudge the DT value.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Add core pll node (core_clk) to manage cpu frequency.
core_clk represents pll itself.
input_clk represents clock signal source (basically xtal) which
comes to pll input.
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

historically axs103 platform code used to set the cpu clk by writing to
PLL registers directly. however the axs10x clk driver is now upstream so
no need to do this amymore.

Driver is selected automatically when CONFIG_ARC_PLAT_AXS10X is set
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: deleted more code not needed anymore]

Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Current implementation relies on L1 line length which might easily
be smaller than L2 line (which is usually the case BTW).

Imagine this typical case: L2 line is 128 bytes while L1 line is
64-bytes. Now we want to allocate small buffer and later use it for DMA
(consider IOC is not available).

kmalloc() allocates small KMALLOC_MIN_SIZE-sized, KMALLOC_MIN_SIZE-aligned
That way if buffer happens to be aligned to L1 line and not L2 line we'll be
flushing and invalidating extra portions of data from L2 which will cause
cache coherency issues.

And since KMALLOC_MIN_SIZE is bound to ARCH_DMA_MINALIGN the fix could
be simple - set ARCH_DMA_MINALIGN to the largest cache line we may ever
get. As of today neither L1 of ARC700 and ARC HS38 nor SLC might not be
longer than 128 bytes.
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

dwmmc driver deprecated num-slots and plan to get rid
of it finally. Just move a step to cleanup it from DT.
Reviewed-by: NJaehoon Chung <jh80.chung@samsung.com>
Acked-by: NAlexey Brodkin <Alexey.Brodkin@synopsys.com>
Acked-by: NVineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Recent commit a8ec3ee8 "arc: Mask individual IRQ lines during core
INTC init" breaks interrupt handling on ARCv2 SMP systems.

That commit masked all interrupts at onset, as some controllers on some
boards (customer as well as internal), would assert interrutps early
before any handlers were installed.  For SMP systems, the masking was
done at each cpu's core-intc.  Later, when the IRQ was actually
requested, it was unmasked, but only on the requesting cpu.

For "common" interrupts, which were wired up from the 2nd level IDU
intc, this was as issue as they needed to be enabled on ALL the cpus
(given that IDU IRQs are by default served Round Robin across cpus)

So fix that by NOT masking "common" interrupts at core-intc, but instead
at the 2nd level IDU intc (latter already being done in idu_of_init())

Fixes: a8ec3ee8 ("arc: Mask individual IRQ lines during core INTC init")
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
[vgupta: reworked changelog, removed the extraneous idu_irq_mask_raw()]
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Preserve eflags and gpa1 aux during entry/exit into kernel as these
could be modified by kernel mode

These registers used by compare exchange instructions.
  - GPA1 is used for compare value,
  - EFLAGS got bit reflects atomic operation response.

EFLAGS is zeroed for each new user task so it won't get its
parent value.
Signed-off-by: NLiav Rehana <liavr@mellanox.com>
Signed-off-by: NNoam Camus <noamc@ezchip.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

save EFLAGS, and GPA1 auxiliary registers during context switch,
since they may be changed by the new task in kernel mode, while using atomic
ops e.g. cmpxchg.
Signed-off-by: NNoam Camus <noamc@ezchip.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

HW bug description: in case of HW thread context switch
the dpc configuration of the exiting thread is dragged
one cycle into the next thread.
In order to avoid the consequences of this bug, the DPC register
is set to an initial value, and not changed afterwards.
Signed-off-by: NElad Kanfi <eladkan@mellanox.com>
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This commit add new configuration that enables us to distinguish
between building the kernel for platforms that have a different set
of auxiliary registers for each cpu and platforms that have a shared
set of auxiliary registers across every thread in each core.
On platforms that implement a different set of auxiliary registers
disabling this configuration insures that we initialize registers on
every cpu and not just for the first thread of the core.
Example for non shared registers is working with EZsim (non silicon)
Signed-off-by: NLiav Rehana <liavr@mellanox.com>
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

We add ability for all cores at NPS SoC to control the number of cycles
HW thread can execute before it is replace with another eligible
HW thread within the same core. The replacement is done by the
HW scheduler.
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: simplified handlign of out of range argument value]

Some of the boot printing code had printk() w/o explicit log level.

This patch introduces consistency allowing platforms to switch to less
verbose console logging using cmdline.

NPS400 with 4K CPUs needs to avoid the cpu info printing for faster
bootup.
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

On ARC700 (and nSIM), user mode memory error triggers an L2 interrupt
which is handled gracefully by kernel (or it tries to despite this being
imprecise, and error could get charged to kernel itself). The offending
task is killed and kernel moves on.

NPS hardware however raises a Machine Check exception for same error
which is NOT recoverable by kernel.

This patch aligns kernel handling for nSIM case, to same as hardware by
overriding the default user space bus error handler.
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NElad Kanfi <eladkan@mellanox.com>
[vgupta: rewrote changelog]
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

When HW threads are active we want CPU to enter idle state only
for the calling HW thread and not to put on sleep all HW threads
sharing this core. For this need the NPS400 got dedicated instruction
so only calling thread is entring sleep and all other are still awake
and can execute instructions.
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: reworked patch to not use inline ifdef but a new function itself]

This paves way for creating a 3rd variant needed for NPS ARC700 without
littering ifdey'ery all over the place
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This way when we execute "ex" during trying to hold lock we can switch to
other HW thread and utilize the core intead of just spinning on a lock.

We noticed about 10% improvement of execution time with hackbench test.
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This counter represents threshold for consecutive stall which
would trigger HW threads scheduling. However when enabled, low
threshhold values cause performance degradation and in the
worst case even livelock.

So disable it by resorting to HW reset value
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Reviewed-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: fixed changelog]

Due to a HW bug in NPS400 we get from time to time false TLB miss.
Workaround this by validating each miss.
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NNoam Camus <noamca@mellanox.com>
Reviewed-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NLiav Rehana <liavr@mellanox.com>
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Reviewed-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NLiav Rehana <liavr@mellanox.com>
Signed-off-by: NNoam Camus <noamca@mellanox.com>
Reviewed-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

There is code duplicated over all architecture's headers for
futex_atomic_op_inuser. Namely op decoding, access_ok check for uaddr,
and comparison of the result.

Remove this duplication and leave up to the arches only the needed
assembly which is now in arch_futex_atomic_op_inuser.

This effectively distributes the Will Deacon's arm64 fix for undefined
behaviour reported by UBSAN to all architectures. The fix was done in
commit 5f16a046 (arm64: futex: Fix undefined behaviour with
FUTEX_OP_OPARG_SHIFT usage). Look there for an example dump.

And as suggested by Thomas, check for negative oparg too, because it was
also reported to cause undefined behaviour report.

Note that s390 removed access_ok check in d12a2970 ("s390/uaccess:
remove pointless access_ok() checks") as access_ok there returns true.
We introduce it back to the helper for the sake of simplicity (it gets
optimized away anyway).
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NRussell King <rmk+kernel@armlinux.org.uk>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [s390]
Acked-by: Chris Metcalf <cmetcalf@mellanox.com> [for tile]
Reviewed-by: NDarren Hart (VMware) <dvhart@infradead.org>
Reviewed-by: Will Deacon <will.deacon@arm.com> [core/arm64]
Cc: linux-mips@linux-mips.org
Cc: Rich Felker <dalias@libc.org>
Cc: linux-ia64@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: peterz@infradead.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: sparclinux@vger.kernel.org
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux-s390@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-hexagon@vger.kernel.org
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-xtensa@linux-xtensa.org
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: openrisc@lists.librecores.org
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Stafford Horne <shorne@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Richard Henderson <rth@twiddle.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-parisc@vger.kernel.org
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-alpha@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20170824073105.3901-1-jslaby@suse.cz