Commit graph

666 commits

Author SHA1 Message Date
Vineet Gupta
6b538db7c6 ARC: dw2 unwind: Catch Dwarf SNAFUs early
Instead of seeing empty stack traces, let kernel fail early so dwarf
issues can be fixed sooner

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-21 14:01:49 +05:30
Vineet Gupta
6d0d506012 ARC: dw2 unwind: Don't bail for CIE.version != 1
The rudimentary CIE.version == 3 handling is already present in code
(for return address register specification)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-21 14:01:25 +05:30
Vineet Gupta
2d64affc92 Revert "ARC: dw2 unwind: Ignore CIE version !=1 gracefully instead of bailing"
Blingly ignoring CIE.version != 1 was a bad idea.
It still leaves "desirability" when running perf with callgraphing where libgcc
symbols might show in hotspot.

More importantly, basic CIE.version == 3 support already exists in code:

|
|   retAddrReg = state.version <= 1 ? *ptr++ : get_uleb128(&ptr, end);
|

Next commit with simply add continue-not-bail for CIE.version != 1

This reverts commit 323f41f9e7.
2015-12-21 13:29:44 +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
Alexey Brodkin
4b32e89af7 ARC: mm: fix building for MMU v2
ARC700 cores with MMU v2 don't have IC_PTAG AUX register and so we only
define ARC_REG_IC_PTAG for MMU versions >= 3.

But current implementation of cache_line_loop_vX() routines assumes
availability of all of them (v2, v3 and v4) simultaneously.

And given undefined ARC_REG_IC_PTAG if CONFIG_MMU_VER=2 we're seeing
compilation problem:
---------------------------------->8-------------------------------
  CC      arch/arc/mm/cache.o
arch/arc/mm/cache.c: In function '__cache_line_loop_v3':
arch/arc/mm/cache.c:270:13: error: 'ARC_REG_IC_PTAG' undeclared (first use in this function)
   aux_tag = ARC_REG_IC_PTAG;
             ^
arch/arc/mm/cache.c:270:13: note: each undeclared identifier is reported only once for each function it appears in
scripts/Makefile.build:258: recipe for target 'arch/arc/mm/cache.o' failed
---------------------------------->8-------------------------------

The simples fix is to have ARC_REG_IC_PTAG defined regardless MMU
version being used.

We don't use it in cache_line_loop_v2() anyways so who cares.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-21 12:10:40 +05:30
Vineet Gupta
899cfd2bb0 ARC: mm: HIGHMEM: Fix section mismatch splat
| WARNING: vmlinux.o(.text+0xd6c2): Section mismatch in reference from the function alloc_kmap_pgtable() to the function
| .init.text:__alloc_bootmem_low()
The function alloc_kmap_pgtable() references the function __init __alloc_bootmem_low().
This is often because alloc_kmap_pgtable lacks a __init annotation or the annotation of __alloc_bootmem_low is wrong.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-21 12:10:40 +05:30
Vineet Gupta
575a9d4e2c ARC: smp: Rename platform hook @init_cpu_smp -> @init_per_cpu
Makes it similar to smp_ops which also has callback with same name

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-17 12:56:56 +05:30
Noam Camus
b474a02382 ARC: rename smp operation init_irq_cpu() to init_per_cpu()
This will better reflect its description i.e. "any needed setup..."
and not just do an "IPI request".

Signed-off-by: Noam Camus <noamc@ezchip.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-17 12:56:43 +05:30
Vineet Gupta
323f41f9e7 ARC: dw2 unwind: Ignore CIE version !=1 gracefully instead of bailing
ARC dwarf unwinder only supports CIE version == 1
The boot time dwarf sanitizer (part of binary lookup table constructor)
would simply bail if it saw CIE version == 3, rendering unwinder with a
NULL lookup table.

It seems libgcc linked with kernel does have such entries.

With fallback linear search removed, and a NULL binary lookup table,
unwinder fails to generate any stack trace.

So allow graceful ignoring of unsupported CIE entries.

This problem was initially seen in Alexey's setup (and not mine) as he
was using buildroot built toolchain (libgcc) which doesn't get built with
CFLAGS_FOR_TARGET="-gdwarf-2 which is my default

Fixes STAR 9000985048: "kernel unwinder broken with stock tools"

Fixes: 2e22502c08 ARC: dw2 unwind: Remove falllback linear search thru FDE entries
Reported-by Alexey Brodkin <abrodkin@synopsys.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-17 11:10:23 +05:30
Vineet Gupta
bc79c9a721 ARC: dw2 unwind: Reinstante unwinding out of modules
The fix which removed linear searching of dwarf (because binary lookup
data always exists) missed out on the fact that modules don't get the
binary lookup tables info. This caused unwinding out of modules to stop
working.

So add binary lookup header setup (equivalent of eh_frame_hdr setup) to
modules as well.

While at it, confine the header setup to within unwinder code,
reducing one API exposed out of unwinder code.

Fixes: 2e22502c08 ARC: dw2 unwind: Remove falllback linear search thru FDE entries
Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-17 11:10:23 +05:30
Vineet Gupta
ff1c0b6a79 ARC: [plat-sim] unbork non default CONFIG_LINUX_LINK_BASE
HIGHMEM support bumped the default memory size for nsim platform to 1G.
Thus total memory ended at the very edge of start of peripherals address
space. With linux link base shifted, memory started bleeding into
peripheral space which caused early boot bad_page spew !

Fixes: 29e332261d ("ARC: mm: HIGHMEM: populate high memory from DT")
Reported-by: Anton Kolesov <akolesov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-17 11:06:43 +05:30
Vineet Gupta
c512c6ba7a ARC: intc: Document arc_request_percpu_irq() better
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-12 16:04:12 +05:30
Vineet Gupta
c6317bc7c5 ARCv2: perf: Ensure perf intr gets enabled on all cores
This was the second perf intr issue

perf sampling on multicore requires intr to be enabled on all cores.
ARC perf probe code used helper arc_request_percpu_irq() which calls
 - request_percpu_irq() on core0
 - enable_percpu_irq() on all all cores (including core0)

genirq requires that request be made ahead of enable call.
However if perf probe happened on non core0 (observed on a 3.18 kernel),
enable would get called ahead of request, failing obviously and
rendering perf intr disabled on all such cores

[   11.120000] 1 ARC perf       : 8 counters (48 bits), 113 conditions, [overflow IRQ support]
[   11.130000] 1 -----> enable_percpu_irq() IRQ 20 failed
[   11.140000] 3 -----> enable_percpu_irq() IRQ 20 failed
[   11.140000] 2 -----> enable_percpu_irq() IRQ 20 failed
[   11.140000] 0 =====> request_percpu_irq() IRQ 20
[   11.140000] 0 -----> enable_percpu_irq() IRQ 20

Fix this fragility, by calling request_percpu_irq() on whatever core
calls probe (there is no requirement on which core calls this anyways)
and then calling enable on each cores.

Interestingly this started as invesigation of STAR 9000838902:
"sporadically IRQs enabled on perf prob"

which was about occassional boot spew as request_percpu_irq got called
non-locally (from an IPI), and re-enabled interrupts in following path
proc_mkdir ->  spin_unlock_irq()

which the irq work code didn't like.

| ARC perf     : 8 counters (48 bits), 113 conditions, [overflow IRQ support]
|
| BUG: failure at ../kernel/irq_work.c:135/irq_work_run_list()!
| CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.18.10-01127-g285efb8e66d1 #2
|
| Stack Trace:
|  arc_unwind_core.constprop.1+0x94/0x104
|  dump_stack+0x62/0x98
|  irq_work_run_list+0xb0/0xb4
|  irq_work_run+0x22/0x3c
|  do_IPI+0x74/0x9c
|  handle_irq_event_percpu+0x34/0x164
|  handle_percpu_irq+0x58/0x78
|  generic_handle_irq+0x1e/0x2c
|  arch_do_IRQ+0x3c/0x60
|  ret_from_exception+0x0/0x8

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: <stable@vger.kernel.org> #4.2+
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-12 16:03:59 +05:30
Vineet Gupta
5bf704c204 ARC: intc: No need to clear IRQ_NOAUTOEN
arc_request_percpu_irq() is called by all cores to request/enable percpu
irq. It has some "prep" calls needed by genirq:
 - setup percpu devid
 - disable IRQ_NOAUTOEN

However given that enable_percpu_irq() is called enayways, latter can be
avoided.

We are now left with irq_set_percpu_devid() quirk and that too for
ARCompact builds only, since previous patch updated ARCv2 intc to do this
in the "right" place, i.e. irq map function.

By next release, this will ultimately be fixed for ARCompact as well.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-12 16:03:59 +05:30
Vineet Gupta
8eb0984bf4 ARCv2: intc: Fix random perf irq disabling in SMP setup
As part of fixing another perf issue, observed that after a perf run,
the interrupt got disabled on one/more cores.

Turns out that despite requesting perf irq as percpu, the flow handler
registered was not handle_percpu_irq()

Given that on ARCv2 cores, IRQs < 24 are always private to cpu, we
register the right handler at the very onset.

Before Fix

| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0      0      0       0  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0    522      8    51916  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0    522      8   104368  ARCv2 core Intc  20 ARC perf counters

After Fix

| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:    0      0      0       0  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20:  64198  62012  62697  67803  ARCv2 core Intc  20 ARC perf counters
|
| [ARCLinux]# perf record -c 20000 /sbin/hackbench
| Running with 10*40 (== 400) tasks.
|
| [ARCLinux]# cat /proc/interrupts | grep perf
|  20: 126014 122792 123301 133654  ARCv2 core Intc  20 ARC perf counters

Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: stable@vger.kernel.org #4.2+
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-12 16:03:41 +05:30
Alexey Brodkin
6d1a2adef7 ARC: [axs10x] cap ethernet phy to 100 Mbit/sec
Current ARC SDP boards cannot reliably handle 1Gbit
Ethernet connections due to limitations in hardware.

To make sure networking is stable on the board we're
limiting phy to 100 Mbit.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-12-07 19:40:03 +05:30
Vineet Gupta
2e22502c08 ARC: dw2 unwind: Remove falllback linear search thru FDE entries
Fixes STAR 9000953410: "perf callgraph profiling causing RCU stalls"

| perf record -g -c 15000 -e cycles /sbin/hackbench
|
| INFO: rcu_preempt self-detected stall on CPU
| 1: (1 GPs behind) idle=609/140000000000002/0 softirq=2914/2915 fqs=603
| Task dump for CPU 1:

in-kernel dwarf unwinder has a fast binary lookup and a fallback linear
search (which iterates thru each of ~11K entries) thus takes 2 orders of
magnitude longer (~3 million cycles vs. 2000). Routines written in hand
assembler lack dwarf info (as we don't support assembler CFI pseudo-ops
yet) fail the unwinder binary lookup, hit linear search, failing
nevertheless in the end.

However the linear search is pointless as binary lookup tables are created
from it in first place. It is impossible to have binary lookup fail while
succeed the linear search. It is pure waste of cycles thus removed by
this patch.

This manifested as RCU stalls / NMI watchdog splat when running
hackbench under perf with callgraph profiling. The triggering condition
was perf counter overflowing in routine lacking dwarf info (like memset)
leading to patheic 3 million cycle unwinder slow path and by the time it
returned new interrupts were already pending (Timer, IPI) and taken
rightaway. The original memset didn't make forward progress, system kept
accruing more interrupts and more unwinder delayes in a vicious feedback
loop, ultimately triggering the NMI diagnostic.

Cc: stable@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-23 21:36:49 +05:30
Vineet Gupta
e81b75f7b2 ARC: remove SYNC from __switch_to()
SYNC in __switch_to() is a historic relic and not needed at all.

 - In UP context it is obviously useless, why would we want to stall
   the core for all updates to stack memory of t0 to complete before
   loading kernel mode callee registers from t1 stack's memory.

 - In SMP, there could be potential race in which outgoing task could
   be concurrently picked for running on a different core, thus writes
   to stack here need to be visible before the reads from stack on
   other core. Peter confirmed that generic schedular already has needed
   barriers (by way of rq lock) so there is no need for additional arch
   barrier.

This came up when Noam was trying to replace this SYNC with EZChip
specific hardware thread scheduling instruction for their platform
support.

Link: http://lkml.kernel.org/r/20151102092654.GM17308@twins.programming.kicks-ass.net
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Cc: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-17 22:05:30 +05:30
Vineet Gupta
b8628f3fe4 ARCv2: Use the default irq priority for idle sleep
Although kernel doesn't support the multiple IRQ priority levels provided
by HS38x core intc yet, ensure that the default prio value is used
anyways by relevant code.

SLEEP insn needs to be provided the IRQ priority level which can
interrupt it. This needs to be the default level which maynot
necessarily be 0 as assumed by current code.

This change allows a kernel with ARCV2_IRQ_DEF_PRIO = 1 to boot fine.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-16 14:17:06 +05:30
Vineet Gupta
512b5b89b9 ARC: Abstract out ISA specific SLEEP args
No semantical changes, prepares for ARCv2 specific change in next commit

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-16 14:17:02 +05:30
Vineet Gupta
61a1634818 ARC: comments update
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-16 12:00:16 +05:30
sujayraaj
17c4fbaf1a ARC: switch to arc-linux- CROSS_COMPILE prefix across all configs
When building kernel with buildroot built toolchain, CROSS_COMPILE
currently needs adjustment even if minor. This is because the defconfigs
prefer "arc-linux-uclibc-" prefix from hand built (non buildroot) toolchain
while buildroot provides "arc-buildroot-linux-uclibc-"

To avoid this use the common "arc-linux-" prefix which is provided by
buildroot and has also been in hand built tools for quite some time.

Signed-off-by: sujayraaj <sujayraaj@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[vgupta: updated changelog]
2015-11-16 12:00:09 +05:30
Linus Torvalds
b3a0d9a232 ARC fixes for 4.4-rc1
- A bunch of brown paper bag bugs (MAINTAINERS list email, SMP build failure)
 - cpu_relax() now compiler barrier for UP as well
 - Handling of userspace Bus Errors for ARCompact builds
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Merge tag 'arc-4.4-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC fixes from Vineet Gupta:
 "Found a couple of brown paper bag bugs with the prev pull request
  (including a SMP build breakage report from Guenter).  Since these are
  urgent I also decided to send over a bunch of other pending fixes
  which could have otherwise waited an rc or two.

  Summary:

   - A bunch of brown paper bag bugs (MAINTAINERS list email, SMP build
     failure)
   - cpu_relax() now compiler barrier for UP as well
   - handling of userspace Bus Errors for ARCompact builds"

* tag 'arc-4.4-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: Fix silly typo in MAINTAINERS file
  ARC: cpu_relax() to be compiler barrier even for UP
  ARC: use ASL assembler mnemonic
  ARC: [arcompact] Handle bus error from userspace as Interrupt not exception
  ARC: remove extraneous header include
  ARCv2: lib: memcpy: use local symbols
2015-11-14 09:09:37 -08:00
Vineet Gupta
1cfc05cbe2 ARC: cpu_relax() to be compiler barrier even for UP
cpu_relax() on ARC has been barrier only for SMP (and no-op for UP). Per
recent discussions, it is safer to make it a compiler barrier
unconditionally.

Link: http://lkml.kernel.org/r/53A7D3AA.9020100@synopsys.com
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-14 13:12:30 +05:30
Vineet Gupta
a6416f57ce ARC: use ASL assembler mnemonic
ARCompact and ARCv2 only have ASL, while binutils used to support LSL as
a alias mnemonic.

Newer binutils (upstream) don't want to do that so replace it.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-14 13:12:21 +05:30
Vineet Gupta
541366da6a ARC: [arcompact] Handle bus error from userspace as Interrupt not exception
Bus errors from userspace on ARCompact based cores are handled by core
as a high priority L2 interrupt but current code treated it as interrupt
Handling an interrupt like exception is certainly not going to go unnoticed.
(and it worked so far as we never saw a Bus error from userspace until
IPPK guys tested a DDR controller with ECC error detection etc hence
needed to explicitly trigger/handle such errors)

 - So move mem_service exception handler from common code into ARCv2 code.
 - In ARCompact code, define  mem_service as L2 interrupt handler which
   just drops down to pure kernel mode and goes of to enqueue SIGBUS

Reported-by: Nelson Pereira <npereira@synopsys.com>
Tested-by: Ana Martins <amartins@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-14 13:12:20 +05:30
Vineet Gupta
76a8c40c65 ARC: remove extraneous header include
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-14 13:11:38 +05:30
Linus Torvalds
9bbd4b9f38 DeviceTree updates for 4.4:
- DT binding doc consolidation moving similar bindings to common
   locations. The majority of these are display related which were
   scattered in video/, fb/, drm/, gpu/, and panel/ directories.
 - Add new config option, CONFIG_OF_ALL_DTBS, to enable building all dtbs
   in the tree for most arches with dts files (except powerpc for now).
 - OF_IRQ=n fixes for user enabled CONFIG_OF.
 - of_node_put ref counting fixes from Julia Lawall.
 - Common DT binding for wakeup-source and deprecation of all similar
   bindings.
 - DT binding for PXA LCD controller.
 - Allow ignoring failed PCI resource translations in order to ignore
   64-bit addresses on non-LPAE 32-bit kernels.
 - Support setting the NUMA node from DT instead of only from parent
   device.
 - Couple of earlycon DT parsing fixes for address and options.
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Merge tag 'devicetree-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull DeviceTree updates from Rob Herring:
 "A fairly large (by DT standards) pull request this time with the
  majority being some overdue moving DT binding docs around to
  consolidate similar bindings.

   - DT binding doc consolidation moving similar bindings to common
     locations.  The majority of these are display related which were
     scattered in video/, fb/, drm/, gpu/, and panel/ directories.

   - Add new config option, CONFIG_OF_ALL_DTBS, to enable building all
     dtbs in the tree for most arches with dts files (except powerpc for
     now).

   - OF_IRQ=n fixes for user enabled CONFIG_OF.

   - of_node_put ref counting fixes from Julia Lawall.

   - Common DT binding for wakeup-source and deprecation of all similar
     bindings.

   - DT binding for PXA LCD controller.

   - Allow ignoring failed PCI resource translations in order to ignore
     64-bit addresses on non-LPAE 32-bit kernels.

   - Support setting the NUMA node from DT instead of only from parent
     device.

   - Couple of earlycon DT parsing fixes for address and options"

* tag 'devicetree-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (45 commits)
  MAINTAINERS: update DT binding doc locations
  devicetree: add Sigma Designs vendor prefix
  of: simplify arch_find_n_match_cpu_physical_id() function
  Documentation: arm: Fixed typo in socfpga fpga mgr example
  Documentation: devicetree: fix reference to legacy wakeup properties
  Documentation: devicetree: standardize/consolidate on "wakeup-source" property
  drivers: of: removing assignment of 0 to static variable
  xtensa: enable building of all dtbs
  mips: enable building of all dtbs
  metag: enable building of all dtbs
  metag: use common make variables for dtb builds
  h8300: enable building of all dtbs
  arm64: enable building of all dtbs
  arm: enable building of all dtbs
  arc: enable building of all dtbs
  arc: use common make variables for dtb builds
  of: add config option to enable building of all dtbs
  of/fdt: fix error checking for earlycon address
  of/overlay: add missing of_node_put
  of/platform: add missing of_node_put
  ...
2015-11-06 12:17:09 -08:00
Linus Torvalds
d63a978865 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking changes from Ingo Molnar:
 "The main changes in this cycle were:

   - More gradual enhancements to atomic ops: new atomic*_read_ctrl()
     ops, synchronize atomic_{read,set}() ordering requirements between
     architectures, add atomic_long_t bitops.  (Peter Zijlstra)

   - Add _{relaxed|acquire|release}() variants for inc/dec atomics and
     use them in various locking primitives: mutex, rtmutex, mcs, rwsem.
     This enables weakly ordered architectures (such as arm64) to make
     use of more locking related optimizations.  (Davidlohr Bueso)

   - Implement atomic[64]_{inc,dec}_relaxed() on ARM.  (Will Deacon)

   - Futex kernel data cache footprint micro-optimization.  (Rasmus
     Villemoes)

   - pvqspinlock runtime overhead micro-optimization.  (Waiman Long)

   - misc smaller fixlets"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ARM, locking/atomics: Implement _relaxed variants of atomic[64]_{inc,dec}
  locking/rwsem: Use acquire/release semantics
  locking/mcs: Use acquire/release semantics
  locking/rtmutex: Use acquire/release semantics
  locking/mutex: Use acquire/release semantics
  locking/asm-generic: Add _{relaxed|acquire|release}() variants for inc/dec atomics
  atomic: Implement atomic_read_ctrl()
  atomic, arch: Audit atomic_{read,set}()
  atomic: Add atomic_long_t bitops
  futex: Force hot variables into a single cache line
  locking/pvqspinlock: Kick the PV CPU unconditionally when _Q_SLOW_VAL
  locking/osq: Relax atomic semantics
  locking/qrwlock: Rename ->lock to ->wait_lock
  locking/Documentation/lockstat: Fix typo - lokcing -> locking
  locking/atomics, cmpxchg: Privatize the inclusion of asm/cmpxchg.h
2015-11-03 16:10:43 -08:00
Linus Torvalds
2c2b8285dc - Support for new MM features in ARCv2 cores (THP, PAE40)
Some generic THP bits are touched - all ACKed by Kirill
 
 - Platform framework updates to prepare for EZChip arrival (still in works)
 
 - ARC Public Mailing list setup finally (linux-snps-arc@lists.infraded.org)
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Merge tag 'arc-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC updates from Vineet Gupta:

 - Support for new MM features in ARCv2 cores (THP, PAE40) Some generic
   THP bits are touched - all ACKed by Kirill

 - Platform framework updates to prepare for EZChip arrival (still in works)

 - ARC Public Mailing list setup finally (linux-snps-arc@lists.infraded.org)

* tag 'arc-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (42 commits)
  ARC: mm: PAE40 support
  ARC: mm: PAE40: tlbex.S: Explicitify the size of pte_t
  ARC: mm: PAE40: switch to using phys_addr_t for physical addresses
  ARC: mm: HIGHMEM: populate high memory from DT
  ARC: mm: HIGHMEM: kmap API implementation
  ARC: mm: preps ahead of HIGHMEM support #2
  ARC: mm: preps ahead of HIGHMEM support
  ARC: mm: use generic macros _BITUL()/_AC()
  ARC: mm: Improve Duplicate PD Fault handler
  MAINTAINERS: Add public mailing list for ARC
  ARC: Ensure DT mem base is same as what kernel is built with
  ARC: boot: Non Master cpus only need to call EARLY_CPU_SETUP once
  ARCv2: smp: [plat-*]: No need to explicitly call mcip_init_smp()
  ARC: smp: Introduce smp hook @init_irq_cpu called for all cores
  ARC: smp: Rename platform hook @init_smp -> @init_cpu_smp
  ARCv2: smp: [plat-*]: No need to explicitly call mcip_init_early_smp()
  ARC: smp: Introduce smp hook @init_early_smp for Master core
  ARC: remove @init_time, @init_irq platform callbacks
  ARC: smp: irqchip: handle IPI as percpu irq like timer
  ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes
  ...
2015-11-03 13:21:09 -08:00
Vineet Gupta
ac506b7f22 ARCv2: lib: memcpy: use local symbols
Otherwise perf profiles don't charge tme to memcpy

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-03 17:33:00 +05:30
Vineet Gupta
5a364c2a17 ARC: mm: PAE40 support
This is the first working implementation of 40-bit physical address
extension on ARCv2.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-29 18:41:30 +05:30
Vineet Gupta
25d464183c ARC: mm: PAE40: tlbex.S: Explicitify the size of pte_t
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 19:50:29 +05:30
Vineet Gupta
28b4af729f ARC: mm: PAE40: switch to using phys_addr_t for physical addresses
That way a single flip of phys_addr_t to 64 bit ensures all places
dealing with physical addresses get correct data

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 19:50:29 +05:30
Vineet Gupta
29e332261d ARC: mm: HIGHMEM: populate high memory from DT
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 19:50:26 +05:30
Vineet Gupta
45890f6d34 ARC: mm: HIGHMEM: kmap API implementation
Implement kmap* API for ARC.

This enables
 - permanent kernel maps (pkmaps): :kmap() API
 - fixmap : kmap_atomic()

We use a very simple/uniform approach for both (unlike some of the other
arches). So fixmap doesn't use the customary compile time address stuff.
The important semantic is sleep'ability (pkmap) vs. not (fixmap) which
the API guarantees.

Note that this patch only enables highmem for subsequent PAE40 support
as there is no real highmem for ARC in pure 32-bit paradigm as explained
below.

ARC has 2:2 address split of the 32-bit address space with lower half
being translated (virtual) while upper half unstranslated
(0x8000_0000 to 0xFFFF_FFFF). kernel itself is linked at base of
unstranslated space (i.e. 0x8000_0000 onwards), which is mapped to say
DDR 0x0 by external Bus Glue logic (outside the core). So kernel can
potentially access 1.75G worth of memory directly w/o need for highmem.
(the top 256M is taken by uncached peripheral space from 0xF000_0000 to
0xFFFF_FFFF)

In PAE40, hardware can address memory beyond 4G (0x1_0000_0000) while
the logical/virtual addresses remain 32-bits. Thus highmem is required
for kernel proper to be able to access these pages for it's own purposes
(user space is agnostic to this anyways).

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 19:49:04 +05:30
Vineet Gupta
6101be5ad4 ARC: mm: preps ahead of HIGHMEM support #2
Explicit'ify that all memory added so far is low memory
Nothing semantical

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 19:49:00 +05:30
Vineet Gupta
336e2136e1 ARC: mm: preps ahead of HIGHMEM support
Before we plug in highmem support, some of code needs to be ready for it
 - copy_user_highpage() needs to be using the kmap_atomic API
 - mk_pte() can't assume page_address()
 - do_page_fault() can't assume VMALLOC_END is end of kernel vaddr space

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 19:31:05 +05:30
Alexey Brodkin
d40846457f ARC: mm: use generic macros _BITUL()/_AC()
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 19:31:05 +05:30
Vineet Gupta
8840e14cd8 ARC: mm: Improve Duplicate PD Fault handler
- Move the verbosity knob from .data to .bss by using inverted logic
 - No need to readout PD1 descriptor
 - clip the non pfn bits of PD0 to avoid clipping inside the loop

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 19:31:04 +05:30
Vineet Gupta
f759ee57b2 ARC: Ensure DT mem base is same as what kernel is built with
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:42 +05:30
Vineet Gupta
483bcc99c0 ARC: boot: Non Master cpus only need to call EARLY_CPU_SETUP once
With prev fixes, all cores now start via common entry point @stext which
already calls EARLY_CPU_SETUP for all cores - so no need to invoke it
again

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:42 +05:30
Vineet Gupta
aa0efcde45 ARCv2: smp: [plat-*]: No need to explicitly call mcip_init_smp()
MCIP now registers it's own per cpu setup routine (for IPI IRQ request)
using smp_ops.init_irq_cpu().

So no need for platforms to do that. This now completely decouples
platforms from MCIP.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:41 +05:30
Vineet Gupta
286130ebf1 ARC: smp: Introduce smp hook @init_irq_cpu called for all cores
Note this is not part of platform owned static machine_desc,
but more of device owned plat_smp_ops (rather misnamed) which a IPI
provider or some such typically defines.

This will help us seperate out the IPI registration from platform
specific init_cpu_smp() into device specific init_irq_cpu()

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:41 +05:30
Vineet Gupta
8721a7f5a6 ARC: smp: Rename platform hook @init_smp -> @init_cpu_smp
This conveys better that it is called for each cpu

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:40 +05:30
Vineet Gupta
26b8f99623 ARCv2: smp: [plat-*]: No need to explicitly call mcip_init_early_smp()
MCIP now registers it's own probe callback with smp_ops.init_early_smp()
which is called by ARC common code, so no need for platforms to do that.

This decouples the platforms and MCIP and helps confine MCIP details
to it's own file.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:40 +05:30
Vineet Gupta
e55af4da02 ARC: smp: Introduce smp hook @init_early_smp for Master core
This adds a platform agnostic early SMP init hook which is called on
Master core before calling setup_processor()

  setup_arch()
     smp_init_cpus()
         smp_ops.init_early_smp()
     ...
     setup_processor()

How this helps:
 - Used for one time init of certain SMP centric IP blocks, before
   calling setup_processor() which probes various bits of core,
   possibly including this block

 - Currently platforms need to call this IP block init from their
   init routines, which doesn't make sense as this is specific to ARC
   core and not platform and otherwise requires copy/paste in all
   (and hence a possible point of failure)

e.g. MCIP init is called from 2 platforms currently (axs10x and sim)
which will go away once we have this.

This change only adds the hooks but they are empty for now. Next commit
will populate them and remove the explicit init calls from platforms.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:40 +05:30
Vineet Gupta
4c82f28617 ARC: remove @init_time, @init_irq platform callbacks
These are not in use for ARC platforms. Moreover DT mechanims exist to
probe them w/o explicit platform calls.

 - clocksource drivers can use CLOCKSOURCE_OF_DECLARE()
 - intc IRQCHIP_DECLARE() calls + cascading inside DT allows external
   intc to be probed automatically

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:39 +05:30
Vineet Gupta
e0868e6f67 ARC: smp: irqchip: handle IPI as percpu irq like timer
The reason this was not done so far was lack of genuine IPI_IRQ for
ARC700, as we don't have a SMP version of core yet (which might change
soon thx to EZChip). Nevertheles to increase the build coverage, we
need to allow CONFIG_SMP for ARC700 and still be able to run it on a
UP platform (nsim or AXS101) with a UP Device Tree (SMP-on-UP)

The build itself requires some define for IPI_IRQ and even a dummy
value is fine since that code won't run anyways.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:13:39 +05:30
Vineet Gupta
3971cdc202 ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes
For Run-on-reset, non masters need to spin wait. For Halt-on-reset they
can jump to entry point directly.

Also while at it, made reset vector handler as "the" entry point for
kernel including host debugger based boot (which uses the ELF header
entry point)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-28 16:08:17 +05:30