Commit Graph

55 Commits

Author SHA1 Message Date
Eugeniy Paltsev
7655146883 ARCv2: Add explcit unaligned access support (and ability to disable too)
As of today we enable unaligned access unconditionally on ARCv2.
Do this under a Kconfig option to allow disable it for test, benchmarking
etc. Also while at it

  - Select HAVE_EFFICIENT_UNALIGNED_ACCESS
  - Although gcc defaults to unaligned access (since GNU 2018.03), add the
    right toggles for enabling or disabling as appropriate
  - update bootlog to prints both HW feature status (exists, enabled/disabled)
    and SW status (used / not used).
  - wire up the relaxed memcpy for unaligned access

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: squashed patches, handle gcc -mno-unaligned-access quick]
2019-02-25 12:10:58 -08:00
Kevin Hilman
b7cc40c32a ARC: change defconfig defaults to ARCv2
Change the default defconfig (used with 'make defconfig') to the ARCv2
nsim_hs_defconfig, and also switch the default Kconfig ISA selection to
ARCv2.

This allows several default defconfigs (e.g. make defconfig, make
allnoconfig, make tinyconfig) to all work with ARCv2 by default.

Note since we change default architecture from ARCompact to ARCv2
it's required to explicitly mention architecture type in ARCompact
defconfigs otherwise ARCv2 will be implied and binaries will be
generated for ARCv2.

Cc: <stable@vger.kernel.org> # 4.4.x
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2018-11-30 10:54:01 -08:00
Linus Torvalds
b27186abb3 Devicetree updates for 4.20:
- Sync dtc with upstream version v1.4.7-14-gc86da84d30e4
 
 - Work to get rid of direct accesses to struct device_node name and
   type pointers in preparation for removing them. New helpers for
   parsing DT cpu nodes and conversions to use the helpers. printk
   conversions to %pOFn for printing DT node names. Most went thru
   subystem trees, so this is the remainder.
 
 - Fixes to DT child node lookups to actually be restricted to child
   nodes instead of treewide.
 
 - Refactoring of dtb targets out of arch code. This makes the support
   more uniform and enables building all dtbs on c6x, microblaze, and
   powerpc.
 
 - Various DT binding updates for Renesas r8a7744 SoC
 
 - Vendor prefixes for Facebook, OLPC
 
 - Restructuring of some ARM binding docs moving some peripheral bindings
   out of board/SoC binding files
 
 - New "secure-chosen" binding for secure world settings on ARM
 
 - Dual licensing of 2 DT IRQ binding headers
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Merge tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull Devicetree updates from Rob Herring:
 "A bit bigger than normal as I've been busy this cycle.

  There's a few things with dependencies and a few things subsystem
  maintainers didn't pick up, so I'm taking them thru my tree.

  The fixes from Johan didn't get into linux-next, but they've been
  waiting for some time now and they are what's left of what subsystem
  maintainers didn't pick up.

  Summary:

   - Sync dtc with upstream version v1.4.7-14-gc86da84d30e4

   - Work to get rid of direct accesses to struct device_node name and
     type pointers in preparation for removing them. New helpers for
     parsing DT cpu nodes and conversions to use the helpers. printk
     conversions to %pOFn for printing DT node names. Most went thru
     subystem trees, so this is the remainder.

   - Fixes to DT child node lookups to actually be restricted to child
     nodes instead of treewide.

   - Refactoring of dtb targets out of arch code. This makes the support
     more uniform and enables building all dtbs on c6x, microblaze, and
     powerpc.

   - Various DT binding updates for Renesas r8a7744 SoC

   - Vendor prefixes for Facebook, OLPC

   - Restructuring of some ARM binding docs moving some peripheral
     bindings out of board/SoC binding files

   - New "secure-chosen" binding for secure world settings on ARM

   - Dual licensing of 2 DT IRQ binding headers"

* tag 'devicetree-for-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (78 commits)
  ARM: dt: relicense two DT binding IRQ headers
  power: supply: twl4030-charger: fix OF sibling-node lookup
  NFC: nfcmrvl_uart: fix OF child-node lookup
  net: stmmac: dwmac-sun8i: fix OF child-node lookup
  net: bcmgenet: fix OF child-node lookup
  drm/msm: fix OF child-node lookup
  drm/mediatek: fix OF sibling-node lookup
  of: Add missing exports of node name compare functions
  dt-bindings: Add OLPC vendor prefix
  dt-bindings: misc: bk4: Add device tree binding for Liebherr's BK4 SPI bus
  dt-bindings: thermal: samsung: Add SPDX license identifier
  dt-bindings: clock: samsung: Add SPDX license identifiers
  dt-bindings: timer: ostm: Add R7S9210 support
  dt-bindings: phy: rcar-gen2: Add r8a7744 support
  dt-bindings: can: rcar_can: Add r8a7744 support
  dt-bindings: timer: renesas, cmt: Document r8a7744 CMT support
  dt-bindings: watchdog: renesas-wdt: Document r8a7744 support
  dt-bindings: thermal: rcar: Add device tree support for r8a7744
  Documentation: dt: Add binding for /secure-chosen/stdout-path
  dt-bindings: arm: zte: Move sysctrl bindings to their own doc
  ...
2018-10-26 12:09:58 -07:00
Rob Herring
37c8a5fafa kbuild: consolidate Devicetree dtb build rules
There is nothing arch specific about building dtb files other than their
location under /arch/*/boot/dts/. Keeping each arch aligned is a pain.
The dependencies and supported targets are all slightly different.
Also, a cross-compiler for each arch is needed, but really the host
compiler preprocessor is perfectly fine for building dtbs. Move the
build rules to a common location and remove the arch specific ones. This
is done in a single step to avoid warnings about overriding rules.

The build dependencies had been a mixture of 'scripts' and/or 'prepare'.
These pull in several dependencies some of which need a target compiler
(specifically devicetable-offsets.h) and aren't needed to build dtbs.
All that is really needed is dtc, so adjust the dependencies to only be
dtc.

This change enables support 'dtbs_install' on some arches which were
missing the target.

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Paul Burton <paul.burton@mips.com>
Acked-by: Ley Foon Tan <ley.foon.tan@intel.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-kbuild@vger.kernel.org
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: uclinux-h8-devel@lists.sourceforge.jp
Cc: linux-mips@linux-mips.org
Cc: nios2-dev@lists.rocketboards.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-xtensa@linux-xtensa.org
Signed-off-by: Rob Herring <robh@kernel.org>
2018-10-02 09:23:21 -05:00
Alexey Brodkin
40660f1fce ARC: build: Don't set CROSS_COMPILE in arch's Makefile
There's not much sense in doing that because if user or
his build-system didn't set CROSS_COMPILE we still may
very well make incorrect guess.

But as it turned out setting CROSS_COMPILE is not as harmless
as one may think: with recent changes that implemented automatic
discovery of __host__ gcc features unconditional setup of
CROSS_COMPILE leads to failures on execution of "make xxx_defconfig"
with absent cross-compiler, for more info see [1].

Set CROSS_COMPILE as well gets in the way if we want only to build
.dtb's (again with absent cross-compiler which is not really needed
for building .dtb's), see [2].

Note, we had to change LIBGCC assignment type from ":=" to "="
so that is is resolved on its usage, otherwise if it is resolved
at declaration time with missing CROSS_COMPILE we're getting this
error message from host GCC:

| gcc: error: unrecognized command line option -mmedium-calls
| gcc: error: unrecognized command line option -mno-sdata

[1] http://lists.infradead.org/pipermail/linux-snps-arc/2018-September/004308.html
[2] http://lists.infradead.org/pipermail/linux-snps-arc/2018-September/004320.html

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2018-09-18 13:24:34 -07:00
Alexey Brodkin
615f64458a ARC: build: Get rid of toolchain check
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: Rob Herring <robh@kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2018-09-13 14:48:05 -07:00
Vineet Gupta
00a99339f0 ARCv2: build: use mcpu=hs38 iso generic mcpu=archs
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: Vineet Gupta <vgupta@synopsys.com>
2018-09-10 09:25:38 -07:00
Masahiro Yamada
2b52e2a67c arc: remove redundant GCC version checks
Commit cafa0010cd ("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: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2018-08-30 17:51:44 -07:00
Masahiro Yamada
d503ac531a kbuild: rename LDFLAGS to KBUILD_LDFLAGS
Commit a0f97e06a4 ("kbuild: enable 'make CFLAGS=...' to add
additional options to CC") renamed CFLAGS to KBUILD_CFLAGS.

Commit 222d394d30 ("kbuild: enable 'make AFLAGS=...' to add
additional options to AS") renamed AFLAGS to KBUILD_AFLAGS.

Commit 06c5040cdb ("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: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-24 08:22:08 +09:00
Alexey Brodkin
74c11e300c ARC: Explicitly add -mmedium-calls to CFLAGS
GCC built for arc*-*-linux has "-mmedium-calls" implicitly enabled by default
thus we don't see any problems during Linux kernel compilation.
----------------------------->8------------------------
arc-linux-gcc -mcpu=arc700 -Q --help=target | grep calls
  -mlong-calls                          [disabled]
  -mmedium-calls                        [enabled]
----------------------------->8------------------------

But if we try to use so-called Elf32 toolchain with GCC configured for
arc*-*-elf* then we'd see the following failure:
----------------------------->8------------------------
init/do_mounts.o: In function 'init_rootfs':
do_mounts.c:(.init.text+0x108): relocation truncated to fit: R_ARC_S21W_PCREL
against symbol 'unregister_filesystem' defined in .text section in fs/filesystems.o

arc-elf32-ld: final link failed: Symbol needs debug section which does not exist
make: *** [vmlinux] Error 1
----------------------------->8------------------------

That happens because neither "-mmedium-calls" nor "-mlong-calls" are enabled in
Elf32 GCC:
----------------------------->8------------------------
arc-elf32-gcc -mcpu=arc700 -Q --help=target | grep calls
  -mlong-calls                          [disabled]
  -mmedium-calls                        [disabled]
----------------------------->8------------------------

Now to make it possible to use Elf32 toolchain for building Linux kernel
we're explicitly add "-mmedium-calls" to CFLAGS.

And since we add "-mmedium-calls" to the global CFLAGS there's no point in
having per-file copies thus removing them.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2018-06-13 17:46:34 -07:00
Masahiro Yamada
d9bc84a808 arc: remove redundant UTS_MACHINE define in arch/arc/Makefile
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: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-10-03 20:36:49 -07:00
Alexey Brodkin
a518d63777 ARC: [plat-hsdk] initial port for HSDK board
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: Rob Herring <robh@kernel.org>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-09-01 11:26:28 -07:00
Vineet Gupta
33460f86ad ARC: [plat-sim] Include this platform unconditionally
Essentially remove CONFIG_ARC_PLAT_SIM

There is no need for any platform specific code, just the board DTS
match strings which we can include unconditionally

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-08-04 13:49:47 +05:30
Michal Marek
5e40f0fd23 arc: Use full path in KBUILD_IMAGE definition
The KBUILD_IMAGE variable is used by the rpm and deb-pkg targets, which
expect it to point to the image file in the build directory. The
builddeb script has a workaround for architectures which only provide
the basename, but let's provide a clean interface for packaging tools.

Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-snps-arc@lists.infradead.org
Signed-off-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-03-20 22:42:20 +09:00
Linus Torvalds
e6251f009b ARC fixes for 4.9-rc5
- mmap handler for dma ops as generic handler no longer works for us [Alexey]
 
  - Fixes for EZChip platform [Noam]
 
  - Fix RTC clocksource driver build issue
 
  - ARC IRQ handling fixes [Yuriy]
 
  - Revert a recent makefile change which doesn't go well with oldish tools out in   the wild
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Merge tag 'arc-4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC fixes from Vineet Gupta:

 - mmap handler for dma ops as generic handler no longer works for us
   [Alexey]

 - Fixes for EZChip platform [Noam]

 - Fix RTC clocksource driver build issue

 - ARC IRQ handling fixes [Yuriy]

 - Revert a recent makefile change which doesn't go well with oldish
   tools out in the wild

* tag 'arc-4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARCv2: MCIP: Use IDU_M_DISTRI_DEST mode if there is only 1 destination core
  ARC: IRQ: Do not use hwirq as virq and vice versa
  ARC: [plat-eznps] set default baud for early console
  ARC: [plat-eznps] remove IPI clear from SMP operations
  Revert "ARC: build: retire old toggles"
  ARC: timer: rtc: implement read loop in "C" vs. inline asm
  ARC: change return value of userspace cmpxchg assist syscall
  arc: Implement arch-specific dma_map_ops.mmap
  ARC: [SMP] avoid overriding present cpumask
  ARC: Enable PERF_EVENTS in nSIM driven platforms
2016-11-11 16:51:50 -08:00
Arnd Bergmann
a76bcf557e Kbuild: enable -Wmaybe-uninitialized warning for "make W=1"
Traditionally, we have always had warnings about uninitialized variables
enabled, as this is part of -Wall, and generally a good idea [1], but it
also always produced false positives, mainly because this is a variation
of the halting problem and provably impossible to get right in all cases
[2].

Various people have identified cases that are particularly bad for false
positives, and in commit e74fc973b6 ("Turn off -Wmaybe-uninitialized
when building with -Os"), I turned off the warning for any build that
was done with CC_OPTIMIZE_FOR_SIZE.  This drastically reduced the number
of false positive warnings in the default build but unfortunately had
the side effect of turning the warning off completely in 'allmodconfig'
builds, which in turn led to a lot of warnings (both actual bugs, and
remaining false positives) to go in unnoticed.

With commit 877417e6ff ("Kbuild: change CC_OPTIMIZE_FOR_SIZE
definition") enabled the warning again for allmodconfig builds in v4.7
and in v4.8-rc1, I had finally managed to address all warnings I get in
an ARM allmodconfig build and most other maybe-uninitialized warnings
for ARM randconfig builds.

However, commit 6e8d666e92 ("Disable "maybe-uninitialized" warning
globally") was merged at the same time and disabled it completely for
all configurations, because of false-positive warnings on x86 that I had
not addressed until then.  This caused a lot of actual bugs to get
merged into mainline, and I sent several dozen patches for these during
the v4.9 development cycle.  Most of these are actual bugs, some are for
correct code that is safe because it is only called under external
constraints that make it impossible to run into the case that gcc sees,
and in a few cases gcc is just stupid and finds something that can
obviously never happen.

I have now done a few thousand randconfig builds on x86 and collected
all patches that I needed to address every single warning I got (I can
provide the combined patch for the other warnings if anyone is
interested), so I hope we can get the warning back and let people catch
the actual bugs earlier.

This reverts the change to disable the warning completely and for now
brings it back at the "make W=1" level, so we can get it merged into
mainline without introducing false positives.  A follow-up patch enables
it on all levels unless some configuration option turns it off because
of false-positives.

Link: https://rusty.ozlabs.org/?p=232 [1]
Link: https://gcc.gnu.org/wiki/Better_Uninitialized_Warnings [2]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-11 08:45:08 -08:00
Vineet Gupta
76a0840474 Revert "ARC: build: retire old toggles"
This has caused a bunch of build failures at a few sites, with GNU
2015.12 and older as the assembler seems to need -mlock to be able to
grok llock/scond instructions for ARC700 builds.
different places since the
older tools still seem to release
of tools which most people are using seem to trip with the -mlock flag
not being passed.

This reverts commit c300547588.
2016-11-08 09:23:52 -08:00
Vineet Gupta
c300547588 ARC: build: retire old toggles
These are really ancient toggles and tools no longer require them to be
passed. This paves way for deprecating them in long run.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-10-28 10:10:27 -07:00
Vineet Gupta
5a205a32ff ARC: dw2 unwind: add infrastructure for adding cfi pseudo ops to asm
1. detect whether binutils supports the cfi pseudo ops
2. define conditional macros to generate the ops
3. define new ENTRY_CFI/END_CFI to annotate hand asm code.
   - Needed because we don't want to emit dwarf info in general ENTRY/END
     used by lowest level trap/exception/interrutp handlers as unwinder
     gets confused trying to unwind out of them. We want unwinder to
     instead stop when it hits onfo those routines
   - These provide minimal start/end cfi ops assuming routine doesn't
     touch stack memory/regs

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30 14:48:22 -07:00
Vineet Gupta
2d04864247 ARC: dw2 unwind: don't force dwarf 2
In .debug_frame based unwinding regime, we used to force -gdwarf-2 since
kernel unwinder only claimed to handle dwarf 2. This changed since commit
6d0d506012 ("ARC: dw2 unwind: Don't bail for CIE.version != 1")
which added some support beyond dwarf 2, atleast to handle CIE != 1

The ill-effect of -gdwarf-2 is that it forces generation of .debug_*
sections, which bloats loadable modules .ko files. For the curious, this
doesn't affect vmlinx binary since linker script discards .debug_* but
same discard is not yet implemented for modules.

So it seems we can drop the -gdwarf-2 toggle, which should not be needed
anyways given that we now use .eh_frame based unwinding.

I've verified using GNU 2016.09-engo10 that the actual unwind info is
not different with or w/o this toggle - but the debug_* sections are
gone for good.

before
-----
arc-linux-readelf -S q_proc.ko-unwinding-1-eh_frame-switch | grep debug
  [15] .debug_info       PROGBITS        00000000 000300 00d08d 00 	0   0  1
  [16] .rela.debug_info  RELA            00000000 0162a0 008844 0c   I 29  15  4
  [17] .debug_abbrev     PROGBITS        00000000 00d38d 0005f8 00 	0   0  1
  [18] .debug_loc        PROGBITS        00000000 00d985 000070 00 	0   0  1
  [19] .rela.debug_loc   RELA            00000000 01eae4 0000c0 0c   I 29  18  4
  [20] .debug_aranges    PROGBITS        00000000 00d9f5 000040 00 	0   0  1
  [21] .rela.debug_arang RELA            00000000 01eba4 000030 0c   I 29  20  4
  [22] .debug_ranges     PROGBITS        00000000 00da35 000018 00 	0   0  1
  [23] .rela.debug_range RELA            00000000 01ebd4 000030 0c   I 29  22  4
  [24] .debug_line       PROGBITS        00000000 00da4d 000b5b 00 	0   0  1
  [25] .rela.debug_line  RELA            00000000 01ec04 0000cc 0c   I 29  24  4
  [26] .debug_str        PROGBITS        00000000 00e5a8 007831 01   MS 0   0  1

after
----

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30 14:48:21 -07:00
Vineet Gupta
6716dbbdef ARC: dw2 unwind: switch to .eh_frame based unwinding
So finally after almost 8 years of dealing with .debug_frame, we are
finally switching to .eh_frame. The reason being stripped kernel
binaries had non-functional unwinder as .debug_frame was gone.
Also, in general .eh_frame seems more common way of doing unwinding.

This also folds a revert of f52e126cc7 ("ARC: unwind: ensure that
.debug_frame is generated (vs. .eh_frame)") to ensure that we start
getting .eh_frame

Reported-by: Daniel Mentz <danielmentz@google.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-09-30 14:48:20 -07:00
Linus Torvalds
6e8d666e92 Disable "maybe-uninitialized" warning globally
Several build configurations had already disabled this warning because
it generates a lot of false positives.  But some had not, and it was
still enabled for "allmodconfig" builds, for example.

Looking at the warnings produced, every single one I looked at was a
false positive, and the warnings are frequent enough (and big enough)
that they can easily hide real problems that you don't notice in the
noise generated by -Wmaybe-uninitialized.

The warning is good in theory, but this is a classic case of a warning
that causes more problems than the warning can solve.

If gcc gets better at avoiding false positives, we may be able to
re-enable this warning.  But as is, we're better off without it, and I
want to be able to see the *real* warnings.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-27 13:17:41 -07:00
Vineet Gupta
f52e126cc7 ARC: unwind: ensure that .debug_frame is generated (vs. .eh_frame)
With recent binutils update to support dwarf CFI pseudo-ops in gas, we
now get .eh_frame vs. .debug_frame. Although the call frame info is
exactly the same in both, the CIE differs, which the current kernel
unwinder can't cope with.

This broke both the kernel unwinder as well as loadable modules (latter
because of a new unhandled relo R_ARC_32_PCREL from .rela.eh_frame in
the module loader)

The ideal solution would be to switch unwinder to .eh_frame.
For now however we can make do by just ensureing .debug_frame is
generated by removing -fasynchronous-unwind-tables

 .eh_frame    generated with -gdwarf-2 -fasynchronous-unwind-tables
 .debug_frame generated with -gdwarf-2

Fixes STAR 9001058196

Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-06-28 09:42:28 +05:30
Andrea Gelmini
2547476a5e Fix typos
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-30 10:07:32 +05:30
Noam Camus
966657890e ARC: Add eznps platform to Kconfig and Makefile
This commit should be left last since only now eznps platform
is in state which one can actually use.
Signed-off-by: Noam Camus <noamc@ezchip.com>
2016-05-09 09:32:33 +05:30
Vineet Gupta
a69fe1a2c9 ARC: build: Turn off -Wmaybe-uninitialized for ARC gcc 4.8
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: Vineet Gupta <vgupta@synopsys.com>
2016-03-18 16:22:36 +05:30
Vineet Gupta
20d780374c ARC: build: Better way to detect ISA compatible toolchain
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: Claudiu Zissulescu <claziss@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-12 11:58:30 +05:30
Vineet Gupta
89a269285f ARC: [BE] Select correct CROSS_COMPILE prefix
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: Vineet Gupta <vgupta@synopsys.com>
2016-03-11 14:59:54 +05:30
Vineet Gupta
0eca6fdb31 ARC: Assume multiplier is always present
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: Vineet Gupta <vgupta@synopsys.com>
2016-02-18 17:30:03 +05:30
Vineet Gupta
07fd7d4bbc ARC: Fix linking errors with CONFIG_MODULE + CONFIG_CC_OPTIMIZE_FOR_SIZE
At -Os, ARC gcc generates millicode thunk for function prologue/epilogue,
which are served by libgcc.

Modules historically are NOT linked with libgcc to avoid code bloat, reducing
runtime relocation fixups etc. I even once tried doing that but got lost
in makefile intricacies.

This means modules at -Os don't get the millicode thunks, causing build
failures below:

| MODPOST 5 modules
| ERROR: "__ld_r13_to_r18" [crypto/sha256_generic.ko] undefined!
| ERROR: "__ld_r13_to_r18_ret" [crypto/sha256_generic.ko] undefined!
| ERROR: "__st_r13_to_r18" [crypto/sha256_generic.ko] undefined!
| ERROR: "__ld_r13_to_r17_ret" [crypto/sha256_generic.ko] undefined!
| ERROR: "__st_r13_to_r17" [crypto/sha256_generic.ko] undefined!
| ERROR: "__ld_r13_to_r16_ret" [crypto/sha256_generic.ko] undefined!
| ERROR: "__st_r13_to_r16" [crypto/sha256_generic.ko] undefined!
|....
|....

Workaround that by inhibiting millicode thunks for loadable modules

Fixes STAR 9000641864:
("Linux built with optimizations for size emits errors for modules")

Reported-by: Anton Kolesov <akolesov@synosys.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-21 13:01:19 +05:30
Rob Herring
10375ccc67 arc: use common make variables for dtb builds
Use dtb-y and always make variables to build dtbs instead of explicit
dtbs rule. This is in preparation to support building all dtbs.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-27 16:12:13 -05:00
Alexey Brodkin
d05a76ab4d ARCv2: add knob for DIV_REV in Kconfig
Being highly configurable core ARC HS among other features might be
configured with or without DIV_REM_OPTION (hardware divider).

That option when enabled adds following instructions: div, divu, rem, remu.

By default ARC HS38 has this option enabled. So we add here possibility
to disable usage of hardware divider by compiler.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-07-20 13:33:30 +03:00
Vineet Gupta
9770906921 ARC: Override toplevel default -O2 with -O3
ARC kernels have historically been built with -O3, despite top level
Makefile defaulting to -O2. This was facilitated by implicitly ordering
of arch makefile include AFTER top level assigned -O2.

An upstream fix to top level a1c48bb160 ("Makefile: Fix unrecognized
cross-compiler command line options") changed the ordering, making ARC
-O3 defunct.

Fix that by NOT relying on any ordering whatsoever and use the proper
arch override facility now present in kbuild (ARCH_*FLAGS)

Depends-on: ("kbuild: Allow arch Makefiles to override {cpp,ld,c}flags")
Suggested-by: Michal Marek <mmarek@suse.cz>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-07-06 11:09:00 +05:30
Vineet Gupta
40b8ad8f76 ARC: Fix build failures for ARCompact in linux-next after ARCv2 support
Reported-by: Guenter Roeck <private@roeck-us.net>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-28 20:30:13 +05:30
Vineet Gupta
d1c6c2fbcd ARCv2: Allow older gcc to cope with new regime of ARCv2/ARCompact support
-no-ll64 is specific to ARCv2 ISA, and is obviously not supported by
older ARC gcc - in this case the one hosted by linux-next sanity build
service.

Ensure that it doesn't get included for ISA_ARCOMPACT

Reported-by: Guenter Roeck <private@roeck-us.net>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-28 19:47:22 +05:30
Vineet Gupta
1f6ccfff63 ARCv2: Support for ARCv2 ISA and HS38x cores
The notable features are:
    - SMP configurations of upto 4 cores with coherency
    - Optional L2 Cache and IO-Coherency
    - Revised Interrupt Architecture (multiple priorites, reg banks,
        auto stack switch, auto regfile save/restore)
    - MMUv4 (PIPT dcache, Huge Pages)
    - Instructions for
	* 64bit load/store: LDD, STD
	* Hardware assisted divide/remainder: DIV, REM
	* Function prologue/epilogue: ENTER_S, LEAVE_S
	* IRQ enable/disable: CLRI, SETI
	* pop count: FFS, FLS
	* SETcc, BMSKN, XBFU...

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-22 14:06:55 +05:30
Alexey Brodkin
556cc1c5f5 ARC: [axs101] Add support for AXS101 SDP (software development platform)
The AXS10x platforms consist of a mainboard with peripherals,
on which several daughter cards can be placed. The daughter cards
typically contain a CPU and memory.

Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:30 +05:30
Vineet Gupta
fd1557923b ARC: [plat_arcfpga]->[plat_sim]
* Remove remanants of legacy ARC FPGA platforms (AA4, ML509...)
* Only nsim simulation platform is left, rename platform accordingly
* AA4 DT stuff is compatible with nsim for ARC700 so rename it too

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:26 +05:30
Vineet Gupta
565a9b497c ARC: RIP broken 64bit RTSC
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:24 +05:30
Vineet Gupta
7c42eaf6c5 ARC: switch to simpler CROSS_COMPILE prefix
ARC GNU tools have had support for arc-linux-* driver for some time now.
This is functionally similar to arc-linux-uclibc-* but uclibc prefix
seemed weird at best when trying to compile the kernel itself.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-05-19 11:27:13 +05:30
Vineet Gupta
7a70bf797a ARC: rename default defconfig
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-12-17 15:23:56 +05:30
Vineet Gupta
68d8feee85 ARC: remove gcc mpy heuristics
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-10-13 14:46:17 +05:30
Vineet Gupta
5a45da02cf ARC: Adjustments for gcc 4.8
* DWARF unwinder related
  + Force DWARF2 compliant .debug_frame (gcc 4.8 defaults to DWARF4
    which kernel unwinder can't grok).
  + Discard the additional .eh_frame generated
  + Discard the dwarf4 debug info generated by -gdwarf-2 for normal
    no debug case

* 4.8 already uses arc600 multilibs for -mno-mpy

* switch to using uclibc compiler (to get -mmedium-calls and -mno-sdata)
  and also since buildroot can only use 1 toolchain

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-27 14:35:32 +05:30
Vineet Gupta
8235703e10 ARC: Use kconfig helper IS_ENABLED() to get rid of defines.h
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-22 13:46:42 +05:30
Christian Ruppert
072eb69390 ARC: [TB10x] Add support for TB10x platform
Infrastructure required to make the Linux kernel compile and boot on the
Abilis Systems TB10x series of SOCs based on ARC700 CPUs:
  - Kmake related files (Kconfig, Makefile, tb10x_defconfig)
  - TB10x platform initialisation

Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Pierrick Hascoet <pierrick.hascoet@abilis.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-05-07 13:43:59 +05:30
Vineet Gupta
104058ede7 ARC: [build] Allow uncompressed uImage
The existing uImage target always generates gzip compressed image which
drags bootup for some very slow FPGA customer boards.

So introduce seperate make targets:uImage.{bin,gz} with uncompressed
being default. Also tie gz generation to CONFIG_KERNEL_GZIP, which a
platform can select in it's Kconfig if it wishes gz to be default.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-04-09 12:21:15 +05:30
Vineet Gupta
fb0990bbf5 ARC: [build] cleanup Makefile a bit
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-04-09 12:21:15 +05:30
Vineet Gupta
af4c3ae399 ARC: [build] silence make defconfig warnings with host gcc 4.7
We do cross compiles for ARC Linux.
With gcc 4.7, a make defconfig spews out the following:

------------------->8--------------------------
make ARCH=arc defconfig
gcc: error: unrecognized command line option '-marc600'
gcc: error: unrecognized command line option '-mA7'
gcc: error: unrecognized command line option '-mno-sdata'
gcc: error: unrecognized command line option '-mno-mpy'
*** Default configuration is based on 'fpga_defconfig'
------------------->8--------------------------

This apparently is coming from LIBGCC line - which is strange to be
invoked for defconfig generation.

Reported-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-04-09 12:21:15 +05:30
Vineet Gupta
e97ff121ae ARC: [Review] Multi-platform image #4: Isolate platform headers
-Top level ARC makefile removes -I for platform headers
-asm/irq.h no longer includes plat/irq.h

-platform makefile adds -I for it's specfic platform headers
-platform code to directly include it's plat/irq.h

-Linker script needed plat/memmap.h for CCM info, already in .config

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:14 +05:30
Vineet Gupta
af61742813 ARC: Boot #2: Verbose Boot reporting / feature verification
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:07 +05:30