Commit Graph

347 Commits

Author SHA1 Message Date
Vineet Gupta 2328af0c9c ARC: [SMP] Enable icache coherency
icaches are not snooped hence not cohrent in SMP setups which means
kernel has to do cross core calls to ensure the same.

The leaf routine __ic_line_inv_vaddr() now does cross core calls.

__sync_icache_dcache() is affected due to this:

* local dcache line flushed ahead of remote icache inv requests
* can't disable interrupts anymore, since
      __ic_line_inv_vaddr()->on_each_cpu() can deadlock.

| WARNING: CPU: 0 PID: 1 at kernel/smp.c:374
| smp_call_function_many+0x25a/0x2c4()
|
|  init_kprobes+0x90/0xc8
|     register_kprobe+0x1d6/0x510
|	__sync_icache_dcache+0x28/0x80
|
|	    DISABLE IRQ
|
|	    __ic_line_inv_vaddr
|		on_each_cpu
|		     smp_call_function_many+0x25a/0x2c4   --> WARN
|			__ic_line_inv_vaddr_local
|	    __dc_line_op

* TODO: Needs to use mask of relevant CPUs to avoid broadcasting

Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-26 11:59:01 +05:30
Noam Camus 7e5122190b ARC: [SMP] Fix IPI IRQ registration
Handle it just like timer. Current request_percpu_irq() would fail on
non-boot cpus and thus IRQ will remian unmasked on those cpus.

[vgupta: fix changelong]
Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-26 11:58:25 +05:30
Anton Kolesov a4b6cb735b ARC: Implement ptrace(PTRACE_GET_THREAD_AREA)
This patch adds implementation of GET_THREAD_AREA ptrace request type. This
is required by GDB to debug NPTL applications.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-26 10:14:08 +05:30
Vineet Gupta bef444a330 ARC: optimize kernel bss clearing in early boot code
using ARC ZOL which reduces tot num of instructions by half

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-26 10:14:05 +05:30
Vineet Gupta ba25915fb2 ARC: Fix build breakage for !CONFIG_ARC_DW2_UNWIND
Fixes: ec7ac6afd0 (ARC: switch to generic ENTRY/END assembler annotations)
Reported-by: Anton Kolesov <akolesov@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-26 10:14:02 +05:30
Vineet Gupta 760ecbc7d0 ARC: fix build warning in devtree
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-23 11:50:26 +05:30
Paul Bolle 230a15f171 ARC: remove checks for CONFIG_ARC_MMU_V4
There's no Kconfig symbol ARC_MMU_V4 so the checks for CONFIG_ARC_MMU_V4
will always evaluate to false. Remove them.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-16 11:34:29 +05:30
Linus Torvalds 9b651cc227 Merge tag 'arc-v3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC updates from Vineet Gupta:
 "Nothing too exciting here, just minor fixes/cleanup.  Only noteworthy
  ones are:

   - Moving cache disabling to early boot
   - ARC UART enabled only if earlyprintk setup in cmdline"

* tag 'arc-v3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: Disable caches in early boot if so configured
  ARC: [arcfpga] Early ARC UART to be only activated by cmdline
  ARC: [arcfpga] Get rid of legacy BVCI latency unit support
  ARC: remove duplicate header exports
  ARC: arc_local_timer_setup() need not pass own cpu id
  ARC: Fixed spelling errors within comments
  ARC: make start_thread() out-of-line
  ARC: fix mmuv2 warning
  ARC: [SMP] ISS SMP extension bitrot
2014-06-09 18:05:11 -07:00
Davidlohr Bueso 5040573e49 arc: call find_vma with the mmap_sem held
Performing vma lookups without taking the mm->mmap_sem is asking for
trouble.  While doing the search, the vma in question can be modified or
even removed before returning to the caller.  Take the lock (shared) in
order to avoid races while iterating through the vmacache and/or rbtree.

[akpm@linux-foundation.org: CSE current->active_mm, per Vineet]
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:00 -07:00
Linus Torvalds d27050641e Merge tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux into next
Pull DeviceTree updates from Rob Herring:
 - Another round of clean-up of FDT related code in architecture code.
   This removes knowledge of internal FDT details from most
   architectures except powerpc.
 - Conversion of kernel's custom FDT parsing code to use libfdt.
 - DT based initialization for generic serial earlycon.  The
   introduction of generic serial earlycon support went in through the
   tty tree.
 - Improve the platform device naming for DT probed devices to ensure
   unique naming and use parent names instead of a global index.
 - Fix a race condition in of_update_property.
 - Unify the various linker section OF match tables and fix several
   function prototype errors.
 - Update platform_get_irq_byname to work in deferred probe cases.
 - 2 binding doc updates

* tag 'devicetree-for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (58 commits)
  of: handle NULL node in next_child iterators
  of/irq: provide more wrappers for !CONFIG_OF
  devicetree: bindings: Document micrel vendor prefix
  dt: bindings: dwc2: fix required value for the phy-names property
  of_pci_irq: kill useless variable in of_irq_parse_pci()
  of/irq: do irq resolution in platform_get_irq_byname()
  of: Add a testcase for of_find_node_by_path()
  of: Make of_find_node_by_path() handle /aliases
  of: Create unlocked version of for_each_child_of_node()
  lib: add glibc style strchrnul() variant
  of: Handle memory@0 node on PPC32 only
  pci/of: Remove dead code
  of: fix race between search and remove in of_update_property()
  of: Use NULL for pointers
  of: Stop naming platform_device using dcr address
  of: Ensure unique names without sacrificing determinism
  tty/serial: pl011: add DT based earlycon support
  of/fdt: add FDT serial scanning for earlycon
  of/fdt: add FDT address translation support
  serial: earlycon: add DT support
  ...
2014-06-04 10:02:38 -07:00
Linus Torvalds 776edb5931 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
Pull core locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - reduced/streamlined smp_mb__*() interface that allows more usecases
     and makes the existing ones less buggy, especially in rarer
     architectures

   - add rwsem implementation comments

   - bump up lockdep limits"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  rwsem: Add comments to explain the meaning of the rwsem's count field
  lockdep: Increase static allocations
  arch: Mass conversion of smp_mb__*()
  arch,doc: Convert smp_mb__*()
  arch,xtensa: Convert smp_mb__*()
  arch,x86: Convert smp_mb__*()
  arch,tile: Convert smp_mb__*()
  arch,sparc: Convert smp_mb__*()
  arch,sh: Convert smp_mb__*()
  arch,score: Convert smp_mb__*()
  arch,s390: Convert smp_mb__*()
  arch,powerpc: Convert smp_mb__*()
  arch,parisc: Convert smp_mb__*()
  arch,openrisc: Convert smp_mb__*()
  arch,mn10300: Convert smp_mb__*()
  arch,mips: Convert smp_mb__*()
  arch,metag: Convert smp_mb__*()
  arch,m68k: Convert smp_mb__*()
  arch,m32r: Convert smp_mb__*()
  arch,ia64: Convert smp_mb__*()
  ...
2014-06-03 12:57:53 -07:00
Vineet Gupta ef680cdc24 ARC: Disable caches in early boot if so configured
Requested-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-03 15:14:48 +05:30
Vineet Gupta e87a850b9c ARC: [arcfpga] Early ARC UART to be only activated by cmdline
Earlier CONFIG_SERIAL_ARC_CONSOLE would unconditionally enable the
legacy ARC UART based early console even if platform lacked that UART
(e.g. nSIM OSCI platform).

So a multi-platform image containing the 2 UART drivers won't work.

Fix that by probing the driver only if "earlyprintk=ttyARC0" is present
in cmdline.

Reported-by: Chuck Jordan <cjordan@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-03 14:20:09 +05:30
Vineet Gupta c00bfd974f ARC: [arcfpga] Get rid of legacy BVCI latency unit support
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-03 13:28:32 +05:30
Vineet Gupta 26bc8a9fcf ARC: remove duplicate header exports
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-03 13:26:53 +05:30
Vineet Gupta 2d4899f6bd ARC: arc_local_timer_setup() need not pass own cpu id
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-06-03 13:26:52 +05:30
Rob Herring eafd370dfe Merge branch 'dt-bus-name' into for-next 2014-05-13 18:34:35 -05:00
Terence Eden f63f98ea25 ARC: Fixed spelling errors within comments
[vgupta: fixed changelong + added Randy's suggestion]
Signed-off-by: Terence Eden <github.com@shkspr.mobi>
Acked-by: Randy Dunlap <rdunlap@infradead.org>

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-05-05 14:22:12 +05:30
Vineet Gupta 2ab402dfd6 ARC: make start_thread() out-of-line
Helps move out ISA specific bits from a arch exported header

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-05-05 14:22:12 +05:30
Vineet Gupta d75386363e ARC: fix mmuv2 warning
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-05-05 14:22:12 +05:30
Vineet Gupta 9a091d9e84 ARC: [SMP] ISS SMP extension bitrot
* Move extension specific code out of common SMP code
* Don't enable it by default for SMP

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-05-05 14:22:12 +05:30
Vineet Gupta 8aa9e85ada ARC: !PREEMPT: Ensure Return to kernel mode is IRQ safe
There was a very small race window where resume to kernel mode from a
Exception Path (or pure kernel mode which is true for most of ARC
exceptions anyways), was not disabling interrupts in restore_regs,
clobbering the exception regs

Anton found the culprit call flow (after many sleepless nights)

| 1. we got a Trap from user land
| 2. started to service it.
| 3. While doing some stuff on user-land memory (I think it is padzero()),
|     we got a DataTlbMiss
| 4. On return from it we are taking "resume_kernel_mode" path
| 5. NEED_RESHED is not set, so we go to "return from exception" path in
|     restore regs.
| 6. there seems to be IRQ happening

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: <stable@vger.kernel.org>   #3.10, 3.12, 3.13, 3.14
Cc: Anton Kolesov <Anton.Kolesov@synopsys.com>
Cc: Francois Bedard <Francois.Bedard@synopsys.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-30 08:21:43 -07:00
Rob Herring 9d0c4dfedd of/fdt: update of_get_flat_dt_prop in prep for libfdt
Make of_get_flat_dt_prop arguments compatible with libfdt fdt_getprop
call in preparation to convert FDT code to use libfdt. Make the return
value const and the property length ptr type an int.

Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>
2014-04-30 00:59:15 -05:00
Rob Herring ccf3356e6b of/fdt: consolidate built-in dtb section variables
Unify the various architectures __dtb_start and __dtb_end definitions
moving them into of_fdt.h.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-metag@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux@lists.openrisc.net
Cc: linux-xtensa@linux-xtensa.org
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>
2014-04-30 00:59:13 -05:00
Vineet Gupta 64ee9f32c3 ARC: Delete stale barrier.h
Commit 93ea02bb84 ("arch: Clean up asm/barrier.h implementations")
wired generic barrier.h for ARC, but failed to delete the existing file.

In 3.15, due to rcupdate.h updates, this causes a build breakage on ARC:

      CC      arch/arc/kernel/asm-offsets.s
    In file included from include/linux/sched.h:45:0,
                     from arch/arc/kernel/asm-offsets.c:9:
    include/linux/rculist.h: In function __list_add_rcu:
    include/linux/rculist.h:54:2: error: implicit declaration of function smp_store_release [-Werror=implicit-function-declaration]
      rcu_assign_pointer(list_next_rcu(prev), new);
      ^

Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-18 13:49:15 -07:00