This reverts commit 667a490b.

This is needed to get ethernet(stmmac) working in 4.6-rc2 on axs103.

4.5 needed this fix, but apprently stmmac has gained some fixes which
warrant reversal of this.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

During mmaping of frame-buffer pages to user-space
fb_protect() is called to set proper page settings.

In case of ARC we need to mark pages that are mmaped to
user as uncached because of 2 reasons:
 * Huge amount of data if passing through data cache will
   thrash cache a lot making cache almost useless for other
   less traffic hungry processes.
 * Data written by user in FB will be immediately available for
   hardware (such as PGU etc) without requirements to flush data
   cache regularly.
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Cc: linux-snps-arc@lists.infradead.org
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Commit 5f8fc432 ("PCI: Include pci/pcie/Kconfig directly from
pci/Kconfig") in linux-next changed drivers/pci/Kconfig to include
drivers/pci/pcie/Kconfig itself, so that architectures do not need
to source both files themselves. ARC just recently gained PCI support
through commit 6b3fb77998dd ("ARC: Add PCI support"), but this change
was based on the old behaviour of the Kconfig files. This makes
Kconfig now spit out the following warnings:

drivers/pci/pcie/Kconfig:61:warning: choice value used outside its choice group
drivers/pci/pcie/Kconfig:67:warning: choice value used outside its choice group
drivers/pci/pcie/Kconfig:74:warning: choice value used outside its choice group

This change updates the Kconfig file for ARC, dropping the now
unnecessary 'source' statement, which makes the warning disappear.
Signed-off-by: NAndreas Ziegler <andreas.ziegler@fau.de>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

The peripheral address space is architectural address window which is
uncached and typically used to wire up peripherals.

For ARC700 cores (ARCompact ISA based) this was fixed to 1GB region
0xC000_0000 - 0xFFFF_FFFF.

For ARCv2 based HS38 cores the start address is flexible and can be
0xC, 0xD, 0xE, 0xF 000_000 by programming AUX_NON_VOLATILE_LIMIT reg
(typically done in bootloader)

Further in cas of PAE, the physical address can extend beyond 4GB so
need to confine this check, otherwise all pages beyond 4GB will be
treated as uncached
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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

To support dma in physical memory beyond 4GB with PAE40
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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

Previously a non-coherent page (hardware IOC or simply driver needs)
could be handled by cpu with paddr alone (kvaddr used to be needed for
coherent mappings to enforce uncached semantics via a MMU mapping).

Now however such a page might still require a V-P mapping if it was in
physical address space > 32bits due to PAE40, which the CPU can't access
directly with a paddr

So decouple decision of kvaddr allocation from type of alloc request
(coh/non-coh)
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

vs. the ones which reutne void *, so that we can handle pages > 4GB
in subsequent patches

Also plug a potential page leak in case ioremap fails
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

linux-next has been reporting gazillion warnings for ARC build and
I finally decided to take a bite:

http://kisskb.ellerman.id.au/kisskb/buildresult/12638735/

Most of the them are due to -Wmaybe-uninitialized

| ../kernel/sysctl.c: In function '__do_proc_doulongvec_minmax':
| ../kernel/sysctl.c:1928:12: warning: 'p' may be used uninitialized in this function [-Wmaybe-uninitialized]
|   ret = tmp - *buf;
|            ^
| ../kernel/sysctl.c:2342:29: note: 'p' was declared here
|  char *kbuf = NULL, *p;
|                     ^
| ...
| ...

Cursory look at code seemed fine and a definite gcc false positive in say
kernel/sysctl.c

Mystery was why only for ARC (and not with ARM linaro toolchain based
off same gcc 4.8). Turns out that -O3 (default for ARC) triggers these
and if I enable -O3 for ARM kernel build, I see the same splat.

I initially wanted to disable this only for gcc 4.8, but Arnd reported
it is seen even on gcc 6.0 for ARM with -O3. Thus better to disable
this independent of gcc version.

Cc: Claudiu Zissulescu <Claudiu.Zissulescu@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-kbuild@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

With THP refcounting work, no need to mark PMDs splitting.

(ARC got missed under the sweeping arch change as THP support was likely
not present in orig baseline)
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit e34d6569 ("stmmac: create of compatible mdio bus for stmmac
driver") broke DW GMAC functionality on ARC AXS10x boards:

That's what happens on eth0 up:
  --------------------------->8------------------------
| libphy: PHY stmmac-0:ffffffff not found
| eth0: Could not attach to PHY
| stmmac_open: Cannot attach to PHY (error: -19)
  --------------------------->8------------------------

Simplest solution is to add PHY description in board's .dts.
And so we do here.
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Phil Reid <preid@electromag.com.au>
Cc: David S. Miller <davem@davemloft.net>
Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: stable@vger.kernel.org # 4.5
Reviewed-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Use helper of_platform_default_populate() in linux/of_platform
when possible, instead of calling of_platform_populate() with
the default match table.
Signed-off-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

linux-next for 4.6-rc1 timeline reported ARC build failures !THP

| arch/arc/include/asm/tlbflush.h:29:0: warning: "flush_pmd_tlb_range" redefined [enabled by default]
| arch/arc/include/asm/tlbflush.h:29:0: warning: "flush_pmd_tlb_range" redefined [enabled by default]
| arch/arc/include/asm/tlbflush.h:29:0: warning: "flush_pmd_tlb_range" redefined [enabled by default]

Turns out that commit ("mm/thp/migration: switch from flush_tlb_range
to flush_pmd_tlb_range") triggered the issue while the problem was in
ARC code where THP specific helpers were not guarded with #ifdef.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Since ezchip network driver was adapted to little endian architecture
this patch provides the corresponding arch/arc/{boot/dts,configs}/ updates so
we can switch over to this device-model/driver for OSCI platform.

Cc: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NLada Trimasova <ltrimas@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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

This patch updates all instances of csum_tcpudp_magic and
csum_tcpudp_nofold to reflect the types that are usually used as the source
inputs.  For example the protocol field is populated based on nexthdr which
is actually an unsigned 8 bit value.  The length is usually populated based
on skb->len which is an unsigned integer.

This addresses an issue in which the IPv6 function csum_ipv6_magic was
generating a checksum using the full 32b of skb->len while
csum_tcpudp_magic was only using the lower 16 bits.  As a result we could
run into issues when attempting to adjust the checksum as there was no
protocol agnostic way to update it.

With this change the value is still truncated as many architectures use
"(len + proto) << 8", however this truncation only occurs for values
greater than 16776960 in length and as such is unlikely to occur as we stop
the inner headers at ~64K in size.

I did have to make a few minor changes in the arm, mn10300, nios2, and
score versions of the function in order to support these changes as they
were either using things such as an OR to combine the protocol and length,
or were using ntohs to convert the length which would have truncated the
value.

I also updated a few spots in terms of whitespace and type differences for
the addresses.  Most of this was just to make sure all of the definitions
were in sync going forward.
Signed-off-by: NAlexander Duyck <aduyck@mirantis.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

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

ARC architecture has 2 instruction sets: ARCompact/ARCv2.
While same gcc supports compiling for either (using appropriate toggles),
we can't use the same toolchain to build kernel because libgcc needs
to be unique and the toolchian (uClibc based) is not multilibed.

uClibc toolchain is convenient since it allows all userspace and
kernel to be built with a single install for an ISA.

This however means 2 gnu installs (with same triplet prefix) are needed
for building for 2 ISA and need to be in PATH.
As developers we keep switching the builds, but would occassionally fail
to update the PATH leading to usage of wrong tools. And this would only
show up at the end of kernel build when linking incompatible libgcc.

So the initial solution was to have gcc define a special preprocessor macro
DEFAULT_CPU_xxx which is unique for default toolchain configuration.
Claudiu proposed using grep for an existing preprocessor macro which is
again uniquely defined per ISA.

Cc: Michal Marek <mmarek@suse.cz>
Suggested-by: NClaudiu Zissulescu <claziss@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This allows for regression testing in PAE specific code as we lack
a 32+ bit physical memory platform other than nSIM.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

read{l,w}() write{l,w}() primitives should use le{16,32}_to_cpu() and
cpu_to_le{16,32}() respectively to ensure device registers are read
correctly in Big Endian CPU configuration.

Per Arnd Bergmann
| Most drivers using readl() or readl_relaxed() expect those to perform byte
| swaps on big-endian architectures, as the registers tend to be fixed endian

This was needed for getting UART to work correctly on a Big Endian ARC.

The ARC accessors originally were fine, and the bug got introduced
inadventently by commit b8a03302 ("ARCv2: barriers")

Fixes: b8a03302 ("ARCv2: barriers")
Link: http://lkml.kernel.org/r/201603100845.30602.arnd@arndb.de
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: stable@vger.kernel.org  [4.2+]
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NLada Trimasova <ltrimas@synopsys.com>
[vgupta: beefed up changelog, added Fixes/stable tags]
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

The problem is with CONFIG_CPU_BIG_ENDIAN=y we still needed .config
fixup to override the the defconfig prefix to arceb-linux-

So remove these from defconfig and let user pass this via CROSS_COMPILE
environment var or use the default for ENDIAN (per previous patch)

No other arch carries them in defconfigs anyways !

Cc: Noam Camus <noamc@ezchip.com>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Anton Kolesov <akolesov@synosys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This allows CONFIG_CPU_BIG_ENDIAN=y to build correctly out of the box,
w/o any other tweaks.

Cc: Noam Camus <noamc@ezchip.com>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Anton Kolesov <akolesov@synosys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

commit 80f42084 removed the ARC bitops microoptimization but failed
to prune the comments to same effect

Fixes: 80f42084 ("ARC: Make ARC bitops "safer" (add anti-optimization)")
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NAdam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Add PCI support to ARC and update drivers/pci Makefile enabling the ARC
arch to use the generic PCI setup functions.

[bhelgaas: fold in Joao's pci-dma-compat.h & pci-bridge.h build fix (I
should have caught this myself, sorry]
Signed-off-by: NJoao Pinto <jpinto@synopsys.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NVineet Gupta <vgupta@synopsys.com>

Let the non boot cpus call into idle with the corresponding hotplug state, so
the hotplug core can handle the further bringup. That's a first step to
convert the boot side of the hotplugged cpus to do all the synchronization
with the other side through the state machine. For now it'll only start the
hotplug thread and kick the full bringup of the cpu.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel <riel@redhat.com>
Cc: Rafael Wysocki <rafael.j.wysocki@intel.com>
Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

They are not symmetric with each other, neither are used in real world
(can not be found by grep command in source code root directory), so
remove them.
Signed-off-by: NChen Gang <gang.chen.5i5j@gmail.com>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

Previous Commit ("ARC: SMP: No need for CONFIG_ARC_IPI_DBG") removed
the Kconfig option ARC_IPI_DBG.  Remove the last reference on this
option.
Signed-off-by: NValentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This was more relevant during SMP bringup.

The warning for bogus msg better be visible always.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

ARConnect/MCIP IPI sending has a retry-wait loop in case caller had
not seen a previous such interrupt. Turns out that it is not needed at
all. Linux cross core calling allows coalescing multiple IPIs to same
receiver - it is fine as long as there is one.

This logic is built into upper layer already, at a higher level of
abstraction. ipi_send_msg_one() sets the actual msg payload, but it only
calls MCIP IPI sending if msg holder was empty (using
atomic-set-new-and-get-old construct). Thus it is unlikely that the
retry-wait looping was ever getting exercised at all.

Cc: Chuck Jordan <cjordan@synopsys.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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

There is no real ARC700 based SMP SoC so remove IPI definition.
EZChip's SMP ARC700 is going to use a different intc and IPI provider
anyways.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

ARConnect/MCIP Inter-Core-Interrupt module can't send interrupt to
local core. So use core intc capability to trigger software
interrupt to self, using an unsued IRQ #21.

This showed up as csd deadlock with LTP trace_sched on a dual core
system. This test acts as scheduler fuzzer, triggering all sorts of
schedulting activity. Trouble starts with IPI to self, which doesn't get
delivered (effectively lost due to H/w capability), but the msg intended
to be sent remain enqueued in per-cpu @ipi_data.

All subsequent IPIs to this core from other cores get elided due to the
IPI coalescing optimization in ipi_send_msg_one() where a pending msg
implies an IPI already sent and assumes other core is yet to ack it.
After the elided IPI, other core simply goes into csd_lock_wait()
but never comes out as this core never sees the interrupt.

Fixes STAR 9001008624

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>        [4.2]
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Even though DEVTMPFS is required when our pre-built initramfs
is used it is not the case in general. It is perfectly possible
to use initramfs with device nodes already populated or there
could be other usages, see discussion below for more detials:
http://thread.gmane.org/gmane.comp.embedded.openwrt.devel/37819/focus=37821

This change removes mentioned dependency from arch/arc/Kconfig
updating instead those defconfigs that are usually used with this
kind of pre-build initramfs.

And while at it all touched defconfigs were regenerated via
savedefconfig and some options were removed:
 * USB is selected by other options implicitly
 * VGA_CONSOLE is disableb for ARC since
   031e29b5
 * EXT3_FS automatically selects EXT4_FS
 * MTDxxx and JFFS2_FS make no sense for AXS because
   AXS NAND controller is not upstreamed
 * NET_OSCI_LAN is not in upstream as well
 * ARCPGU_xxx options make no sense because ARC PGU is not yet
   in upstream and when it gets there all config options would
   be taken from devicetree
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

- ARCv2 uses a seperate BCR for {I,D}CCM base address:
  ARCompact encoded both base/size in same BCR

- Size encoding in common BCR is different for ARCompact/ARCv2
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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

It is unlikely that designs running Linux will not have multiplier.
Further the current support is not complete as tool don't generate a
multilib w/o multiplier.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

MMUv4 supports 2 concurrent page sizes: Normal and Super [4K to 16M]

So far Linux supported a single super page size for a given Normal page,
depending on the software page walking address split.
e.g. we had 11:8:13 address split for 8K page, which meant super page
was 2 ^(8+13) = 2M (given that THP size has to be PMD_SHIFT)

Now we turn this around, by allowing multiple Super Pages in Kconfig
(currently 2M and 16M only) and forcing page walker address split to
PGDIR_SHIFT and PAGE_SHIFT

For configs without Super page, things are same as before and
PGDIR_SHIFT can be hacked to get non default address split

The motivation for this change is a customer who needs 16M super page
and a 8K Normal page combo.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>