This check is very naive: we simply test if GCC invoked without
"-mcpu=XXX" has ARC700 define set. In that case we think that GCC
was built with "--with-cpu=arc700" and has libgcc built for ARC700.

Otherwise if ARC700 is not defined we think that everythng was built
for ARCv2.

But in reality our life is much more interesting.

1. Regardless of GCC configuration (i.e. what we pass in "--with-cpu"
   it may generate code for any ARC core).

2. libgcc might be built with explicitly specified "--mcpu=YYY"

That's exactly what happens in case of multilibbed toolchains:
 - GCC is configured with default settings
 - All the libs built for many different CPU flavors

I.e. that check gets in the way of usage of multilibbed
toolchains. And even non-multilibbed toolchains are affected.
OpenEmbedded also builds GCC without "--with-cpu" because
each and every target component later is compiled with explicitly
set "-mcpu=ZZZ".
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

helps gcc with better instruction selections such as 64-bit multiply MPYD

before
------
82c34b58 <sched_clock>:
82c34b58:	ld	r2,[0x83068d00]
82c34b60:	add_s	r2,r2,0x7530
82c34b66:	mov_s	r0,0x989680
82c34b6c:	mpymu	r5,r2,r0
82c34b70:	mpy	r4,r2,r0
82c34b74:	mov_s	r0,r4
82c34b76:	j_s.d	[blink]
82c34b78:	mov_s	r1,r5
82c34b7a:	nop_s

after
------
82c34b7c <sched_clock>:
82c34b7c:	ld	r0,[0x83064d00]
82c34b84:	add_s	r0,r0,0x7530
82c34b8a:	mpydu	r0,r0,0x989680
82c34b92:	j_s	[blink]
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

__GFP_HIGHMEM flag is cleared by upper layer functions
(in include/linux/dma-mapping.h) so we'll never get a
__GFP_HIGHMEM flag in arch_dma_alloc gfp argument.
That's why alloc_pages will never return highmem page
here.

Get rid of highmem pages handling and cleanup arch_dma_alloc
and arch_dma_free functions.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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

So far the IOC treatment was global on ARC, being turned on (or off)
for all devices in the system. With this patch, this can now be done
per device using the "dma-coherent" DT property; IOW with this patch
we can use both HW-coherent and regular DMA peripherals simultaneously.

The changes involved are too many so enlisting the summary below:

1. common code calls ARC arch_setup_dma_ops() per device.

2. For coherent dma (IOC) it plugs in generic @dma_direct_ops which
   doesn't need any arch specific backend: No need for any explicit
   cache flushes or MMU mappings to provide for uncached access

   - dma_(map|sync)_single* return early as corresponding dma ops callbacks
     are NULL in generic code.
     So arch_sync_dma_*() -> dma_cache_*() need not handle the coherent
     dma case, hence drop ARC __dma_cache_*_ioc() which were no-op anyways

3. For noncoherent dma (non IOC) generic @dma_noncoherent_ops is used
   which in turns calls ARC specific routines

   - arch_dma_alloc() no longer checks for @ioc_enable since this is
     called only for !IOC case.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: rewrote changelog]

Mark DMA devices on AXS103 and HSDK boards connected through IOC
port as dma-coherent.
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

In 4.19-rc1, Eugeniy reported weird boot and IO errors on ARC HSDK

| INFO: task syslogd:77 blocked for more than 10 seconds.
|       Not tainted 4.19.0-rc1-00007-gf213acea4e88 #40
| "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this
| message.
| syslogd         D    0    77     76 0x00000000
|
| Stack Trace:
|  __switch_to+0x0/0xac
|  __schedule+0x1b2/0x730
|  io_schedule+0x5c/0xc0
|  __lock_page+0x98/0xdc
|  find_lock_entry+0x38/0x100
|  shmem_getpage_gfp.isra.3+0x82/0xbfc
|  shmem_fault+0x46/0x138
|  handle_mm_fault+0x5bc/0x924
|  do_page_fault+0x100/0x2b8
|  ret_from_exception+0x0/0x8

He bisected to 84c65911 ("locking/atomics,
asm-generic/bitops/lock.h: Rewrite using atomic_fetch_*()")

This commit however only unmasked the real issue introduced by commit
4aef66c8 ("locking/atomic, arch/arc: Fix build") which missed the
retry-if-scond-failed branch in atomic_fetch_##op() macros.

The bisected commit started using atomic_fetch_##op() macros for building
the rest of atomics.

Fixes: 4aef66c8 ("locking/atomic, arch/arc: Fix build")
Reported-by: NEugeniy Paltsev <paltsev@synopsys.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: wrote changelog]

Commit cafa0010 ("Raise the minimum required gcc version to 4.6")
bumped the minimum GCC version to 4.6 for all architectures.

With GCC >= 4.6 assumed, 'upto_gcc44' is empty, 'atleast_gcc44' is y.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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

 - Remove unused variables
 - check return value of file_path
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

SWAP support on ARC was fixed earlier by
commit 6e376114 ("ARC: Fix CONFIG_SWAP")
so now we may safely enable it on platforms that
have external media like USB and SD-card.

Note: it was already allowed for HSDK
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Cc: stable@vger.kernel.org # 6e376114: ARC: Fix CONFIG_SWAP
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Otherwise kernel uses random MAC which is not very conveniet.
With that change in place use might set desired MAC in U-Boot
with "setenv ethaddr 11:22:33:44:55:66", save environment and
then from boot to boot the same MAC will be used by the kernel.

One other note for this to happen it's required to pass
board's .dtb in U-Boot's "bootm" command like that:
------------------->8-----------------
bootm 0x82000000 - 0x84000000
------------------->8-----------------

Here 0x82000000 is location of uImage while
0x80000000 is location of either axs10x.dtb or hsdk.dtb
previously loaded from SD-card, USB storage or TFTP server.
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: stable@vger.kernel.org # 4.14
Cc: devicetree@vger.kernel.org
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

 - Remove CONFIG_DEFAULT_HOSTNAME from defconfigs

   There's no reason to set the same hostname to all ARC boards
   by default. It usually gets overwritten by init scripts anyways.

 - Remove disabled CONFIG_DEVKMEM from defconfigs

   It is disabled by default
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Commit a0f97e06 ("kbuild: enable 'make CFLAGS=...' to add
additional options to CC") renamed CFLAGS to KBUILD_CFLAGS.

Commit 222d394d ("kbuild: enable 'make AFLAGS=...' to add
additional options to AS") renamed AFLAGS to KBUILD_AFLAGS.

Commit 06c5040c ("kbuild: enable 'make CPPFLAGS=...' to add
additional options to CPP") renamed CPPFLAGS to KBUILD_CPPFLAGS.

For some reason, LDFLAGS was not renamed.

Using a well-known variable like LDFLAGS may result in accidental
override of the variable.

Kbuild generally uses KBUILD_ prefixed variables for the internally
appended options, so here is one more conversion to sanitize the
naming convention.

I did not touch Makefiles under tools/ since the tools build system
is a different world.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: NPalmer Dabbelt <palmer@sifive.com>

Use new return type vm_fault_t for fault handler.  For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno.  Once all instances are converted, vm_fault_t will become a
distinct type.

Ref-> commit 1c8f4220 ("mm: change return type to vm_fault_t")

In this patch all the caller of handle_mm_fault() are changed to return
vm_fault_t type.

Link: http://lkml.kernel.org/r/20180617084810.GA6730@jordon-HP-15-Notebook-PCSigned-off-by: NSouptick Joarder <jrdr.linux@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: David S. Miller <davem@davemloft.net>
Cc: Richard Weinberger <richard@nod.at>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Levin, Alexander (Sasha Levin)" <alexander.levin@verizon.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Almost all architectures include it.  Add a ARCH_NO_PREEMPT symbol to
disable preempt support for alpha, hexagon, non-coldfire m68k and
user mode Linux.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Move the source of lib/Kconfig.debug and arch/$(ARCH)/Kconfig.debug to
the top-level Kconfig.  For two architectures that means moving their
arch-specific symbols in that menu into a new arch Kconfig.debug file,
and for a few more creating a dummy file so that we can include it
unconditionally.

Also move the actual 'Kernel hacking' menu to lib/Kconfig.debug, where
it belongs.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Instead of duplicating the source statements in every architecture just
do it once in the toplevel Kconfig file.

Note that with this the inclusion of arch/$(SRCARCH/Kconfig moves out of
the top-level Kconfig into arch/Kconfig so that don't violate ordering
constraits while keeping a sensible menu structure.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Fix type warnings in arch/arc/mm/cache.c.

../arch/arc/mm/cache.c: In function 'flush_anon_page':
../arch/arc/mm/cache.c:1062:55: warning: passing argument 2 of '__flush_dcache_page' makes integer from pointer without a cast [-Wint-conversion]
  __flush_dcache_page((phys_addr_t)page_address(page), page_address(page));
                                                       ^~~~~~~~~~~~~~~~~~
../arch/arc/mm/cache.c:1013:59: note: expected 'long unsigned int' but argument is of type 'void *'
 void __flush_dcache_page(phys_addr_t paddr, unsigned long vaddr)
                                             ~~~~~~~~~~~~~~^~~~~
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: Elad Kanfi <eladkan@mellanox.com>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Ofer Levi <oferle@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Fix build errors in arch/arc/'s delay.h:
- add "extern unsigned long loops_per_jiffy;"
- add <asm-generic/types.h> for "u64"

In file included from ../drivers/infiniband/hw/cxgb3/cxio_hal.c:32:
../arch/arc/include/asm/delay.h: In function '__udelay':
../arch/arc/include/asm/delay.h:61:12: error: 'u64' undeclared (first use in this function)
  loops = ((u64) usecs * 4295 * HZ * loops_per_jiffy) >> 32;
            ^~~

In file included from ../drivers/infiniband/hw/cxgb3/cxio_hal.c:32:
../arch/arc/include/asm/delay.h: In function '__udelay':
../arch/arc/include/asm/delay.h:63:37: error: 'loops_per_jiffy' undeclared (first use in this function)
  loops = ((u64) usecs * 4295 * HZ * loops_per_jiffy) >> 32;
                                     ^~~~~~~~~~~~~~~
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: Elad Kanfi <eladkan@mellanox.com>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Ofer Levi <oferle@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Fix printk format warning in arch/arc/plat-eznps/mtm.c:

In file included from ../include/linux/printk.h:7,
                 from ../include/linux/kernel.h:14,
                 from ../include/linux/list.h:9,
                 from ../include/linux/smp.h:12,
                 from ../arch/arc/plat-eznps/mtm.c:17:
../arch/arc/plat-eznps/mtm.c: In function 'set_mtm_hs_ctr':
../include/linux/kern_levels.h:5:18: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long int' [-Wformat=]
 #define KERN_SOH "\001"  /* ASCII Start Of Header */
                  ^~~~~~
../include/linux/kern_levels.h:11:18: note: in expansion of macro 'KERN_SOH'
 #define KERN_ERR KERN_SOH "3" /* error conditions */
                  ^~~~~~~~
../include/linux/printk.h:308:9: note: in expansion of macro 'KERN_ERR'
  printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
         ^~~~~~~~
../arch/arc/plat-eznps/mtm.c:166:3: note: in expansion of macro 'pr_err'
   pr_err("** Invalid @nps_mtm_hs_ctr [%d] needs to be [%d:%d] (incl)\n",
   ^~~~~~
../arch/arc/plat-eznps/mtm.c:166:40: note: format string is defined here
   pr_err("** Invalid @nps_mtm_hs_ctr [%d] needs to be [%d:%d] (incl)\n",
                                       ~^
                                       %ld
The hs_ctr variable can just be int instead of long, so also change
kstrtol() to kstrtoint() and leave the format string as %d.

Also add 2 header files since they are used in mtm.c and we prefer
not to depend on accidental/indirect #includes.

Cc: linux-snps-arc@lists.infradead.org
Cc: Ofer Levi <oferle@mellanox.com>
Reviewed-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Add <linux/types.h> to fix build errors.
Both ctop.h and <soc/nps/common.h> use u32 types and cause many
errors.

Examples:
../include/soc/nps/common.h:71:4: error: unknown type name 'u32'
    u32 __reserved:20, cluster:4, core:4, thread:4;
../include/soc/nps/common.h:76:3: error: unknown type name 'u32'
   u32 value;
../include/soc/nps/common.h:124:4: error: unknown type name 'u32'
    u32 base:8, cl_x:4, cl_y:4,
../include/soc/nps/common.h:127:3: error: unknown type name 'u32'
   u32 value;

../arch/arc/plat-eznps/include/plat/ctop.h:83:4: error: unknown type name 'u32'
    u32 gen:1, gdis:1, clk_gate_dis:1, asb:1,
../arch/arc/plat-eznps/include/plat/ctop.h:86:3: error: unknown type name 'u32'
   u32 value;
../arch/arc/plat-eznps/include/plat/ctop.h:93:4: error: unknown type name 'u32'
    u32 csa:22, dmsid:6, __reserved:3, cs:1;
../arch/arc/plat-eznps/include/plat/ctop.h:95:3: error: unknown type name 'u32'
   u32 value;

Cc: linux-snps-arc@lists.infradead.org
Cc: Ofer Levi <oferle@mellanox.com>
Reviewed-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Fixing compilation issue caused by missing struct nps_host_reg_aux_dpc
definition.

Fixes: 3f9cd874 ("ARC: [plat-eznps] avoid toggling of DPC register")
Reported-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NOfer Levi <oferle@mellanox.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Check that SMP_CACHE_BYTES (and hence ARCH_DMA_MINALIGN) is larger
or equal to any cache line length by comparing it with values
previously read from ARC cache BCR registers.
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

As for today we don't setup SMP_CACHE_BYTES and cache_line_size for
ARC, so they are set to L1_CACHE_BYTES by default. L1 line length
(L1_CACHE_BYTES) might be easily smaller than L2 line (which is
usually the case BTW). This breaks code.

For example this breaks ethernet infrastructure on HSDK/AXS103 boards
with IOC disabled, involving manual cache flushes
Functions which alloc and manage sk_buff packet data area rely on
SMP_CACHE_BYTES define. In the result we can share last L2 cache
line in sk_buff linear packet data area between DMA buffer and
some useful data in other structure. So we can lose this data when
we invalidate DMA buffer.

   sk_buff linear packet data area
                |
                |
                |         skb->end        skb->tail
                V            |                |
                             V                V
----------------------------------------------.
      packet data            | <tail padding> |  <useful data in other struct>
----------------------------------------------.

---------------------.--------------------------------------------------.
     SLC line        |             SLC (L2 cache) line (128B)           |
---------------------.--------------------------------------------------.
        ^                                     ^
        |                                     |
     These cache lines will be invalidated when we invalidate skb
     linear packet data area before DMA transaction starting.

This leads to issues painful to debug as it reproduces only if
(sk_buff->end - sk_buff->tail) < SLC_LINE_SIZE and
if we have some useful data right after sk_buff->end.

Fix that by hardcode SMP_CACHE_BYTES to max line length we may have.
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

ARC backend for dma_sync_single_for_(device|cpu) was broken as it was
not honoring the @dir argument and simply forcing it based on the call:
 - arc_dma_sync_single_for_device(dir) assumed DMA_TO_DEVICE (cache wback)
 - arc_dma_sync_single_for_cpu(dir) assumed DMA_FROM_DEVICE (cache inv)

This is not true given the DMA API programming model and has been
discussed here [1] in some detail.

Interestingly while the deficiency has been there forever, it only started
showing up after 4.17 dma common ops rework, commit a8eb92d0
("arc: fix arc_dma_{map,unmap}_page") which wired up these calls under the
more commonly used dma_map_page API triggering the issue.

[1]: https://lkml.org/lkml/2018/5/18/979
Fixes: commit a8eb92d0 ("arc: fix arc_dma_{map,unmap}_page")
Cc: stable@kernel.org # v4.17+
Signed-off-by: NEugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: reworked changelog]

This manifsted as strace segfaulting on HSDK because gcc was targetting
the accumulator registers as GPRs, which kernek was not saving/restoring
by default.

Cc: stable@vger.kernel.org   #4.14+
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

mprotect(EXEC) was failing for stack mappings as default vm flags was
missing MAYEXEC.

This was triggered by glibc test suite nptl/tst-execstack testcase

What is surprising is that despite running LTP for years on, we didn't
catch this issue as it lacks a directed test case.

gcc dejagnu tests with nested functions also requiring exec stack work
fine though because they rely on the GNU_STACK segment spit out by
compiler and handled in kernel elf loader.

This glibc case is different as the stack is non exec to begin with and
a dlopen of shared lib with GNU_STACK segment triggers the exec stack
proceedings using a mprotect(PROT_EXEC) which was broken.

CC: stable@vger.kernel.org
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

swap was broken on ARC due to silly copy-paste issue.

We encode offset from swapcache page in __swp_entry() as (off << 13) but
were not decoding back in __swp_offset() as (off >> 13) - it was still
(off << 13).

This finally fixes swap usage on ARC.

| # mkswap /dev/sda2
|
| # swapon -a -e /dev/sda2
| Adding 500728k swap on /dev/sda2.  Priority:-2 extents:1 across:500728k
|
| # free
|              total       used       free     shared    buffers     cached
| Mem:        765104      13456     751648       4736          8       4736
| -/+ buffers/cache:       8712     756392
| Swap:       500728          0     500728

Cc: stable@vger.kernel.org
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This is a non functional code changw, which moves r25 restore from macro
into the caller of macro
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

We used to have pre-set CONFIG_INITRAMFS_SOURCE with local path
to intramfs in ARC defconfigs. This was quite convenient for
in-house development but not that convenient for newcomers
who obviusly don't have folders like "arc_initramfs" next to
the Linux source tree. Which leads to quite surprising failure
of defconfig building:
------------------------------->8-----------------------------
  ../scripts/gen_initramfs_list.sh: Cannot open '../../arc_initramfs_hs/'
../usr/Makefile:57: recipe for target 'usr/initramfs_data.cpio.gz' failed
make[2]: *** [usr/initramfs_data.cpio.gz] Error 1
------------------------------->8-----------------------------

So now when more and more people start to deal with our defconfigs
let's make their life easier with removal of CONFIG_INITRAMFS_SOURCE.
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: stable@vger.kernel.org
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Since commit eedf265a ("devpts: Make each mount of devpts an
independent filesystem.") CONFIG_DEVPTS_MULTIPLE_INSTANCES isn't needed
in the defconfig anymore.
Signed-off-by: NAnders Roxell <anders.roxell@linaro.org>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This is used in configs lacking hardware atomics to emulate atomic r-m-w
for user space, implemented by disabling preemption in kernel.

However there are issues in current implementation:

1. Process not terminated if invalid user pointer passed:
   i.e. __get_user() failed.

2. The reason for this patch was __put_user() failure not being handled
   either, specifically for the COW break scenario.
   The zero page is initially wired up and read from __get_user()
   succeeds. A subsequent write by __put_user() induces a
   Protection Violation, but COW can't finish as Linux page fault
   handler is disabled due to preempt disable.
   And what's worse is we silently return the stale value to user space.
   Fix this specific case by re-enabling preemption and explicitly
   fixing up the fault and retrying the whole sequence over.

Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-arch@vger.kernel.org
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
[vgupta: rewrote the changelog]

In case of HSDK we have intermediate INTC in for of DW APB GPIO controller
which is used as a de-bounce logic for interrupt wires that come from
outside the board.

We cannot use existing "irq-dw-apb-ictl" driver here because all input
lines are routed to corresponding output lines but not muxed into one
line (this is configured in RTL and we cannot change this in software).

But even if we add such a feature to "irq-dw-apb-ictl" driver that won't
benefit us as higher-level INTC (in case of HSDK it is IDU) anyways has
per-input control so adding fully-controller intermediate INTC will only
bring some overhead on interrupt processing but no other benefits.

Thus we just do one-time configuration of DW APB GPIO controller and
forget about it.

Based on implementation available on arch/arc/plat-axs10x/axs10x.c file.
Acked-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NGustavo Pimentel <gustavo.pimentel@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Add PCI support to the ARC HSDK platform allowing to use the generic PCI
setup functions.
Signed-off-by: NGustavo Pimentel <gustavo.pimentel@synopsys.com>
Acked-by: NAlexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

The ifdeffery for atomic*_{fetch_,}andnot() is unlike that for all the
other atomics. If atomic*_andnot() is not defined, the corresponding
atomic*_fetch_andnot() is assumed to not be defined.

Additionally, the fallbacks for the various ordering cases are written
much later in atomic.h as static inlines.

This isn't problematic today, but gets in the way of scripting the
generation of atomics. To prepare for scripting, this patch:

* Switches to separate ifdefs for atomic*_andnot() and
  atomic*_fetch_andnot(), updating implementations as appropriate.

* Moves the fallbacks into the standards ifdefs, as macro expansions
  rather than static inlines.

* Removes trivial andnot implementations from architectures, where these
  are superseded by core code.

There should be no functional change as a result of this patch.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-19-mark.rutland@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The conditional inc/dec ops differ for atomic_t and atomic64_t:

- atomic_inc_unless_positive() is optional for atomic_t, and doesn't exist for atomic64_t.
- atomic_dec_unless_negative() is optional for atomic_t, and doesn't exist for atomic64_t.
- atomic_dec_if_positive is optional for atomic_t, and is mandatory for atomic64_t.

Let's make these consistently optional for both. At the same time, let's
clean up the existing fallbacks to use atomic_try_cmpxchg().

The instrumented atomics are updated accordingly.

There should be no functional change as a result of this patch.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-18-mark.rutland@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Many of the inc/dec ops are mandatory, but for most architectures inc/dec are
simply trivial wrappers around their corresponding add/sub ops.

Let's make all the inc/dec ops optional, so that we can get rid of these
boilerplate wrappers.

The instrumented atomics are updated accordingly.

There should be no functional change as a result of this patch.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NPalmer Dabbelt <palmer@sifive.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-17-mark.rutland@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Some of the atomics return the result of a test applied after the atomic
operation, and almost all architectures implement these as trivial
wrappers around the underlying atomic. Specifically:

 * <atomic>_inc_and_test(v)    is (<atomic>_inc_return(v)    == 0)
 * <atomic>_dec_and_test(v)    is (<atomic>_dec_return(v)    == 0)
 * <atomic>_sub_and_test(i, v) is (<atomic>_sub_return(i, v) == 0)
 * <atomic>_add_negative(i, v) is (<atomic>_add_return(i, v)  < 0)

Rather than have these definitions duplicated in all architectures, with
minor inconsistencies in formatting and documentation, let's make these
operations optional, with default fallbacks as above. Implementations
must now provide a preprocessor symbol.

The instrumented atomics are updated accordingly.

Both x86 and m68k have custom implementations, which are left as-is,
given preprocessor symbols to avoid being overridden.

There should be no functional change as a result of this patch.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NPalmer Dabbelt <palmer@sifive.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20180621121321.4761-16-mark.rutland@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

As a step towards unifying the atomic/atomic64/atomic_long APIs, this
patch converts the arch/arc implementation of atomic64_add_unless() into
an implementation of atomic64_fetch_add_unless().

A wrapper in <linux/atomic.h> will build atomic_add_unless() atop of
this, provided it is given a preprocessor definition.

No functional change is intended as a result of this patch.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vineet Gupta <vgupta@synopsys.com>
Link: https://lore.kernel.org/lkml/20180621121321.4761-11-mark.rutland@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>