Commit Graph

218 Commits

Author SHA1 Message Date
Linus Torvalds
9d3bc3d4a4 ARC updates for 4.8-rc1
Things have been calm here - nothing much except for a few fixes
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Merge tag 'arc-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC updates from Vineet Gupta:
 "Things have been calm here - nothing much except for a few fixes"

* tag 'arc-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: mm: don't loose PTE_SPECIAL in pte_modify()
  ARC: dma: fix address translation in arc_dma_free
  ARC: typo fix in mm/ioremap.c
  ARC: fix linux-next build breakage
2016-07-29 13:17:34 -07:00
Kirill A. Shutemov
dcddffd41d mm: do not pass mm_struct into handle_mm_fault
We always have vma->vm_mm around.

Link: http://lkml.kernel.org/r/1466021202-61880-8-git-send-email-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Vladimir Kondratiev
b4dff28740 ARC: dma: fix address translation in arc_dma_free
page should be calculated using physical address.
If platform uses non-trivial dma-to-phys memory translation,
dma_handle should be converted to physicval address before
calculation of page.

Failing to do so results in struct page * pointing to
wrong or non-existent memory.

Fixes: f2e3d55397 ("ARC: dma: reintroduce platform specific dma<->phys")
Cc: stable@vger.kernel.org #4.6+
Signed-off-by: Vladimir Kondratiev <vladimir.kondratiev@intel.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-07-20 09:54:22 -07:00
Alexey Brodkin
627c88b68f ARC: typo fix in mm/ioremap.c
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-07-19 13:57:34 -07:00
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
8bcf2c48f3 ARC: [plat-eznps] Use dedicated user stack top
NPS use special mapping right below TASK_SIZE.
Hence we need to lower STACK_TOP so that user stack won't
overlap NPS special mapping.

Signed-off-by: Noam Camus <noamc@ezchip.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09 09:32:32 +05:30
Noam Camus
15ca68a993 ARC: Make vmalloc size configurable
On ARC, lower 2G of address space is translated and used for
 - user vaddr space (region 0 to 5)
 - unused kernel-user gutter (region 6)
 - kernel vaddr space (region 7)

where each region simply represents 256MB of address space.

The kernel vaddr space of 256MB is used to implement vmalloc, modules
So far this was enough, but not on EZChip system with 4K CPUs (given
that per cpu mechanism uses vmalloc for allocating chunks)

So allow VMALLOC_SIZE to be configurable by expanding down into the unused
kernel-user gutter region which at default 256M was excessive anyways.

Also use _BITUL() to fix a build error since PGDIR_SIZE cannot use "1UL"
as called from assembly code in mm/tlbex.S

Signed-off-by: Noam Camus <noamc@ezchip.com>
[vgupta: rewrote changelog, debugged bootup crash due to int vs. hex]
Acked-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-09 09:32:32 +05:30
Vineet Gupta
26f9d5fd82 ARC: support HIGHMEM even without PAE40
Initial HIGHMEM support on ARC was introduced for PAE40 where the low
memory (0x8000_0000 based) and high memory (0x1_0000_0000) were
physically contiguous. So CONFIG_FLATMEM sufficed (despite a peipheral
hole in the middle, which wasted a bit of struct page memory, but things
worked).

However w/o PAE, highmem was not possible and we could only reach
~1.75GB of DDR. Now there is a use case to access ~4GB of DDR w/o PAE40
The idea is to have low memory at canonical 0x8000_0000 and highmem
at 0 so enire 4GB address space is available for physical addressing
This needs additional platform/interconnect mapping to convert
the non contiguous physical addresses into linear bus adresses.

From Linux point of view, non contiguous divide means FLATMEM no
longer works and DISCONTIGMEM is needed to track the pfns in the 2
regions.

This scheme would also work for PAE40, only better in that we don't
waste struct page memory for the peripheral hole.

The DT description will be something like

    memory {
        ...
        reg = <0x80000000 0x200000000   /* 512MB: lowmem */
               0x00000000 0x10000000>;  /* 256MB: highmem */
   }

Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-05-05 16:35:46 +05:30
Alexey Brodkin
1b10cb21d8 ARC: add support for reserved memory defined by device tree
Enable reserved memory initialization from device tree.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-04-27 17:06:56 +05:30
Kirill A. Shutemov
09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Vineet Gupta
deaf7565eb ARCv2: ioremap: Support dynamic peripheral address space
The peripheral address space is architectural address window which is
uncached and typically used to wire up peripherals.

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

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

Further in cas of PAE, the physical address can extend beyond 4GB so
need to confine this check, otherwise all pages beyond 4GB will be
treated as uncached

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-19 14:34:10 +05:30
Vineet Gupta
f2e3d55397 ARC: dma: reintroduce platform specific dma<->phys
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-19 14:34:09 +05:30
Vineet Gupta
f5db19e93f ARC: dma: ioremap: use phys_addr_t consistenctly in code paths
To support dma in physical memory beyond 4GB with PAE40

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-19 14:34:09 +05:30
Vineet Gupta
971573cf57 ARC: dma: pass_phys() not sg_virt() to cache ops
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-19 14:34:09 +05:30
Vineet Gupta
6b7003930e ARC: dma: non-coherent pages need V-P mapping if in HIGHMEM
Previously a non-coherent page (hardware IOC or simply driver needs)
could be handled by cpu with paddr alone (kvaddr used to be needed for
coherent mappings to enforce uncached semantics via a MMU mapping).

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

So decouple decision of kvaddr allocation from type of alloc request
(coh/non-coh)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-19 14:34:08 +05:30
Vineet Gupta
d98a15a565 ARC: dma: Use struct page based page allocator helpers
vs. the ones which reutne void *, so that we can handle pages > 4GB
in subsequent patches

Also plug a potential page leak in case ioremap fails

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-19 14:34:08 +05:30
Adam Buchbinder
7423cc0cae ARC: Fix misspellings in comments.
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2016-03-11 14:59:53 +05:30
Christoph Hellwig
052c96dbe3 arc: convert to dma_map_ops
[vgupta@synopsys.com: ARC: dma mapping fixes #2]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Carlos Palminha <CARLOS.PALMINHA@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-20 17:09:18 -08:00
Kirill A. Shutemov
e1534ae950 mm: differentiate page_mapped() from page_mapcount() for compound pages
Let's define page_mapped() to be true for compound pages if any
sub-pages of the compound page is mapped (with PMD or PTE).

On other hand page_mapcount() return mapcount for this particular small
page.

This will make cases like page_get_anon_vma() behave correctly once we
allow huge pages to be mapped with PTE.

Most users outside core-mm should use page_mapcount() instead of
page_mapped().

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:32 -08:00
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
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
61a1634818 ARC: comments update
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-11-16 12:00:16 +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
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
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
d0890ea5b6 ARC: boot log: decode more mmu config items
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-17 17:48:26 +05:30
Vineet Gupta
964cf28f9d ARC: boot log: move helper macros to header for reuse
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-17 17:48:25 +05:30
Vineet Gupta
b598e17f6a ARC: mm: compute TLB size as needed from ways * sets
This frees up some bits to hold more high level info such as PAE being
present, w/o increasing the size of already bloated cpuinfo struct

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-17 17:48:25 +05:30
Vineet Gupta
c7119d56d2 ARCv2: mm: THP: flush_pmd_tlb_range make SMP safe
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-17 17:48:21 +05:30
Vineet Gupta
722fe8fd36 ARCv2: mm: THP: Implement flush_pmd_tlb_range() optimization
Implement the TLB flush routine to evict a sepcific Super TLB entry,
vs. moving to a new ASID on every such flush.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-17 17:48:21 +05:30
Vineet Gupta
6ce187985f ARCv2: mm: THP: boot validation/reporting
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-17 17:48:18 +05:30
Vineet Gupta
fe6c1b8611 ARCv2: mm: THP support
MMUv4 in HS38x cores supports Super Pages which are basis for Linux THP
support.

Normal and Super pages can co-exist (ofcourse not overlap) in TLB with a
new bit "SZ" in TLB page desciptor to distinguish between them.
Super Page size is configurable in hardware (4K to 16M), but fixed once
RTL builds.

The exact THP size a Linx configuration will support is a function of:
 - MMU page size (typical 8K, RTL fixed)
 - software page walker address split between PGD:PTE:PFN (typical
   11:8:13, but can be changed with 1 line)

So for above default, THP size supported is 8K * 256 = 2M

Default Page Walker is 2 levels, PGD:PTE:PFN, which in THP regime
reduces to 1 level (as PTE is folded into PGD and canonically referred
to as PMD).

Thus thp PMD accessors are implemented in terms of PTE (just like sparc)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-17 17:48:18 +05:30
Vineet Gupta
129cbed54a ARC: mm: pte flags comsetic cleanups, comments
No semantical changes

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-09 17:04:22 +05:30
Vineet Gupta
fd0881a24a ARC: Eliminate some ARCv2 specific code for ARCompact build
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-08-21 15:06:43 +05:30
Alexey Brodkin
1648c70d30 ARCv2: IOC: Allow boot time disable
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-08-20 18:15:31 +05:30
Vineet Gupta
79335a2ca0 ARCv2: SLC: Allow boot time disable
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-08-20 18:11:52 +05:30
Alexey Brodkin
f2b0b25a37 ARCv2: Support IO Coherency and permutations involving L1 and L2 caches
In case of ARCv2 CPU there're could be following configurations
that affect cache handling for data exchanged with peripherals
via DMA:
 [1] Only L1 cache exists
 [2] Both L1 and L2 exist, but no IO coherency unit
 [3] L1, L2 caches and IO coherency unit exist

Current implementation takes care of [1] and [2].
Moreover support of [2] is implemented with run-time check
for SLC existence which is not super optimal.

This patch introduces support of [3] and rework of DMA ops
usage. Instead of doing run-time check every time a particular
DMA op is executed we'll have 3 different implementations of
DMA ops and select appropriate one during init.

As for IOC support for it we need:
 [a] Implement empty DMA ops because IOC takes care of cache
     coherency with DMAed data
 [b] Route dma_alloc_coherent() via dma_alloc_noncoherent()
     This is required to make IOC work in first place and also
     serves as optimization as LD/ST to coherent buffers can be
     srviced from caches w/o going all the way to memory

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
[vgupta:
  -Added some comments about IOC gains
  -Marked dma ops as static,
  -Massaged changelog a bit]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-08-20 18:11:17 +05:30
Vineet Gupta
f718c2efff ARC: Don't memzero twice in dma_alloc_coherent for __GFP_ZERO
alloc_pages_exact() get gfp flags and handle zero'ing already

And while it, fix the case where ioremap fails: return rightaway.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-07-06 11:09:01 +05:30
Alexey Brodkin
b607eddd71 ARCv2: guard SLC DMA ops with spinlock
SLC maintenance ops need to be serialized by software as there is no
inherent buffering / quequing of aux commands. It can silently ignore a
new aux operation if previous one is still ongoing (SLC_CTRL_BUSY)

So gaurd the SLC op using a spin lock

The spin lock doesn't seem to be contended even in heavy workloads such
as iperf. On FPGA @ 75 MHz.

 [1] Before this change:
 ============================================================
  # iperf -c 10.42.0.1
 ------------------------------------------------------------
 Client connecting to 10.42.0.1, TCP port 5001
 TCP window size: 43.8 KByte (default)
 ------------------------------------------------------------
 [  3] local 10.42.0.110 port 38935 connected with 10.42.0.1 port 5001
 [ ID] Interval       Transfer     Bandwidth
 [  3]  0.0-10.0 sec  48.4 MBytes  40.6 Mbits/sec
 ============================================================

 [2] After this change:
 ============================================================
 # iperf -c 10.42.0.1
 ------------------------------------------------------------
 Client connecting to 10.42.0.1, TCP port 5001
 TCP window size: 43.8 KByte (default)
 ------------------------------------------------------------
 [  3] local 10.42.0.243 port 60248 connected with 10.42.0.1 port 5001
 [ ID] Interval       Transfer     Bandwidth
 [  3]  0.0-10.0 sec  47.5 MBytes  39.8 Mbits/sec
 # iperf -c 10.42.0.1
 ------------------------------------------------------------
 Client connecting to 10.42.0.1, TCP port 5001
 TCP window size: 43.8 KByte (default)
 ------------------------------------------------------------
 [  3] local 10.42.0.243 port 60249 connected with 10.42.0.1 port 5001
 [ ID] Interval       Transfer     Bandwidth
 [  3]  0.0-10.0 sec  54.9 MBytes  46.0 Mbits/sec
 ============================================================

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Cc: arc-linux-dev@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-07-06 10:12:39 +05:30
Linus Torvalds
0890a26479 - Support for HS38 cores based on ARCv2 ISA
ARCv2 is the next generation ISA from Synopsys and basis for the
      HS3{4,6,8} families of processors which retain the traditional ARC mantra of
      low power and configurability and are now more performant and feature rich.
 
      HS38x is a 10 stage pipeline core which supports MMU (with huge pages) and
      SMP (upto 4 cores) among other features.
 
      + www.synopsys.com/dw/ipdir.php?ds=arc-hs38-processor
      + http://news.synopsys.com/2014-10-14-New-DesignWare-ARC-HS38-Processor-Doubles-Performance-for-Embedded-Linux-Applications
      + http://www.embedded.com/electronics-news/4435975/Synopsys-ARC-HS38-core-gives-2X-boost-to-Linux-based-apps
 
  - Support for ARC SDP (Software Development platform): Main Board + CPU Cards
     = AXS101: CPU Card with ARC700 in silicon @ 700 MHz
     = AXS103: CPU Card with HS38x in FPGA
 
  - Refactoring of ARCompact port to accomodate new ARCv2 ISA
  - Miscll updates/cleanups
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Merge tag 'arc-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC architecture updates from Vineet Gupta:

 - support for HS38 cores based on ARCv2 ISA

     ARCv2 is the next generation ISA from Synopsys and basis for the
     HS3{4,6,8} families of processors which retain the traditional ARC mantra of
     low power and configurability and are now more performant and feature rich.

     HS38x is a 10 stage pipeline core which supports MMU (with huge pages) and
     SMP (upto 4 cores) among other features.

     + www.synopsys.com/dw/ipdir.php?ds=arc-hs38-processor
     + http://news.synopsys.com/2014-10-14-New-DesignWare-ARC-HS38-Processor-Doubles-Performance-for-Embedded-Linux-Applications
     + http://www.embedded.com/electronics-news/4435975/Synopsys-ARC-HS38-core-gives-2X-boost-to-Linux-based-apps

 - support for ARC SDP (Software Development platform): Main Board + CPU Cards
    = AXS101: CPU Card with ARC700 in silicon @ 700 MHz
    = AXS103: CPU Card with HS38x in FPGA

 - refactoring of ARCompact port to accomodate new ARCv2 ISA

 - misc updates/cleanups

* tag 'arc-4.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (72 commits)
  ARC: Fix build failures for ARCompact in linux-next after ARCv2 support
  ARCv2: Allow older gcc to cope with new regime of ARCv2/ARCompact support
  ARCv2: [vdk] dts files and defconfig for HS38 VDK
  ARCv2: [axs103] Support ARC SDP FPGA platform for HS38x cores
  ARC: [axs101] Prepare for AXS103
  ARCv2: [nsim*hs*] Support simulation platforms for HS38x cores
  ARCv2: All bits in place, allow ARCv2 builds
  ARCv2: SLC: Handle explcit flush for DMA ops (w/o IO-coherency)
  ARCv2: STAR 9000837815 workaround hardware exclusive transactions livelock
  ARC: Reduce bitops lines of code using macros
  ARCv2: barriers
  arch: conditionally define smp_{mb,rmb,wmb}
  ARC: add smp barriers around atomics per Documentation/atomic_ops.txt
  ARC: add compiler barrier to LLSC based cmpxchg
  ARCv2: SMP: intc: IDU 2nd level intc for dynamic IRQ distribution
  ARCv2: SMP: clocksource: Enable Global Real Time counter
  ARCv2: SMP: ARConnect debug/robustness
  ARCv2: SMP: Support ARConnect (MCIP) for Inter-Core-Interrupts et al
  ARC: make plat_smp_ops weak to allow over-rides
  ARCv2: clocksource: Introduce 64bit local RTC counter
  ...
2015-07-01 09:24:26 -07:00
Ruud Derwig
2924cd18c4 ARCv2: [vdk] dts files and defconfig for HS38 VDK
- CONFIG_ARC_UBOOT_SUPPORT to handle arguments passed in r0, r1, r2
 - CONFIG_DEVTMPFS_MOUNT for mouting rootfs since it uses external cpio
   for rootfs

Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Ruud Derwig <rderwig@synopsys.com>
[vgupta: folded the Main baord DT files for smp/up into one]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-25 06:00:21 +05:30
Vineet Gupta
795f455856 ARCv2: SLC: Handle explcit flush for DMA ops (w/o IO-coherency)
L2 cache on ARCHS processors is called SLC (System Level Cache)
For working DMA (in absence of hardware assisted IO Coherency) we need
to manage SLC explicitly when buffers transition between cpu and
controllers.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-25 06:00:19 +05:30
Vineet Gupta
bcc4d65abe ARCv2: MMUv4: support aliasing icache config
This is also default for AXS103 release

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-22 14:06:56 +05:30
Vineet Gupta
d1f317d825 ARCv2: MMUv4: cache programming model changes
Caveats about cache flush on ARCv2 based cores

- dcache is PIPT so paddr is sufficient for cache maintenance ops (no
  need to setup PTAG reg

- icache is still VIPT but only aliasing configs need PTAG setup

So basically this is departure from MMU-v3 which always need vaddr in
line ops registers (DC_IVDL, DC_FLDL, IC_IVIL) but paddr in DC_PTAG,
IC_PTAG respectively.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-22 14:06:55 +05:30
Vineet Gupta
d7a512bfe0 ARCv2: MMUv4: TLB programming Model changes
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-22 14:06:55 +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
Vineet Gupta
a615b47dbf ARC: entry.S: confine EXCEPTION_* macros to one file
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:35 +05:30
Vineet Gupta
11e14896ea ARC: untangle cache flush loop
- Remove the ifdef'ery and write distinct versions for each mmu ver even
  if there is some code duplication

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:33 +05:30
Vineet Gupta
6c31068137 ARC: cacheflush: No need to retain DC_CTRL from __before_dc_op()
That is because __after_dc_op() already reads it for status check, so it
is better anyways to use that "newer" value.

Also reduces the clutter in callers for passing from/to these routines.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:33 +05:30
Vineet Gupta
8ea2ddff41 ARC: cacheflush: move some code around, delete old comments
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:33 +05:30
Vineet Gupta
8362c389a4 ARC: mm/cache_arc700.c -> mm/cache.c
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:32 +05:30
Vineet Gupta
40b552d95a ARC: compress cpuinfo_arc_mmu (mainly save page size in KB)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:25 +05:30
Vineet Gupta
454bfda9ac ARC: remove the unused platform helpers from dma mapping API
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-06-19 18:09:23 +05:30
David Hildenbrand
70ffdb9393 mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler
Introduce faulthandler_disabled() and use it to check for irq context and
disabled pagefaults (via pagefault_disable()) in the pagefault handlers.

Please note that we keep the in_atomic() checks in place - to detect
whether in irq context (in which case preemption is always properly
disabled).

In contrast, preempt_disable() should never be used to disable pagefaults.
With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt
counter, and therefore the result of in_atomic() differs.
We validate that condition by using might_fault() checks when calling
might_sleep().

Therefore, add a comment to faulthandler_disabled(), describing why this
is needed.

faulthandler_disabled() and pagefault_disable() are defined in
linux/uaccess.h, so let's properly add that include to all relevant files.

This patch is based on a patch from Thomas Gleixner.

Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 08:39:15 +02:00
Vineet Gupta
4530949350 ARC: fold ___flush_dcache_page into __flush_dcache_page
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-05-19 11:27:13 +05:30
Vineet Gupta
4a8a224570 ARC: inline cache flush toggle helpers
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-05-11 11:21:41 +05:30
Vineet Gupta
f2e2013f75 ARC: mem init spring cleaning - No functional changes
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-04-13 15:16:29 +05:30
Vineet Gupta
ceed97ab4f ARC: perf: Enable generic software events
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-02-27 10:15:01 +05:30
Guenter Roeck
e262eb9381 arc: mm: Fix build failure
Fix misspelled define.

Fixes: 33692f2759 ("vm: add VM_FAULT_SIGSEGV handling support")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-30 10:31:14 -08:00
Linus Torvalds
33692f2759 vm: add VM_FAULT_SIGSEGV handling support
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d45 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-01-29 10:51:32 -08:00
Vineet Gupta
5637208253 ARC: boot: cpu feature print enhancements
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-10-13 14:46:22 +05:30
Vineet Gupta
c59414cca1 ARC: refactoring: reduce the scope of some local vars
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-10-13 14:46:18 +05:30
Noam Camus
014018e0b4 ARC: [mm] Fix compilation breakage
Structure name and variable name were erroneously interchanged

Signed-off-by: Noam Camus <noamc@ezchip.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
[ Also removed pointless cast from "void *".  - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-03 10:08:50 -07:00
Pranith Kumar
e356030519 flush_icache_range: export symbol to fix build errors
Fix building errors occuring due to a missing export of
flush_icache_range() in

kisskb.ellerman.id.au/kisskb/buildresult/11677809/

ERROR: "flush_icache_range" [drivers/misc/lkdtm.ko] undefined!

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>	[arc]
Acked-by: Richard Kuo <rkuo@codeaurora.org>	[hexagon]
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>	[xtensa]
Cc: Noam Camus <noamc@ezchip.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Zhigang Lu <zlu@tilera.com>		[tile]
Cc: Kirill Tkhai <tkhai@yandex.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-29 16:28:17 -07:00
David Rientjes
2a5e95d418 mm, arc: remove obsolete pagefault oom killer comment
Commit 609838cfed ("mm: invoke oom-killer from remaining unconverted page
fault handlers") converted arc to call pagefault_out_of_memory(), so remove
the comment about future conversion.

Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-08-07 16:10:59 -07:00
Vineet Gupta
af5abf1b04 ARC: help gcc elide icache helper for !SMP
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-07-23 11:30:24 +05:30
Vineet Gupta
1b1a22b133 ARC: move common ops for line/full cache into helpers
INV cmd for dcache provides 2 modes discard or wback-before-discard.
One is default and other needs to be set, if so desired. This is common
for line-op/entire-cache-op. So refactor them out into a helper

Doesn't affect generated code but paves way for any common
micro-optimization.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-07-23 11:30:20 +05:30
Vineet Gupta
da40ff48bd ARC: cache boot reporting updates
* print aliasing or not, VIPT/PIPT etc
* compress param storage using bitfields
* more use of IS_ENABLED to de-uglify code

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-07-23 11:22:10 +05:30
Vineet Gupta
c9a98e1849 ARC: update some comments
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-07-23 11:17:12 +05:30
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
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
d75386363e ARC: fix mmuv2 warning
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-05-05 14:22:12 +05:30
Vineet Gupta
c3441edd2d ARC: [SMP] General Fixes
-Pass the expected arg to non-boot park'ing routine
 (It worked so far because existing SMP backends don't use the arg)

-CONFIG_DEBUG_PREEMPT warning
2014-04-05 14:46:42 +05:30
Vineet Gupta
ec7ac6afd0 ARC: switch to generic ENTRY/END assembler annotations
With commit 9df62f0544 "arch: use ASM_NL instead of ';'" the generic
macros can handle the arch specific newline quirk. Hence we can get rid
of ARC asm macros and use the "C" style macros.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-03-26 14:31:28 +05:30
Noam Camus
d6579e99bc ARC: support external initrd
Currently ARC only supports embedded initrd. This patch enables
external ones too.

[vgupta: Changed from "rt_start"=start/"rd_size"=sz to unified "initrd"=start,sz]
Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-03-26 14:31:27 +05:30
Vineet Gupta
b053940df4 ARC: Use correct PTAG register for icache flush
This fixes a subtle issue with cache flush which could potentially cause
random userspace crashes because of stale icache lines.

This error crept in when consolidating the cache flush code

Fixes: bd12976c36 (ARC: cacheflush refactor #3: Unify the {d,i}cache)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org  # 3.13
Cc: arc-linux-dev@synopsys.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-07 10:12:56 -08:00
Linus Torvalds
10d0c9705e DeviceTree updates for 3.13. This is a bit larger pull request than
usual for this cycle with lots of clean-up.
 
 - Cross arch clean-up and consolidation of early DT scanning code.
 - Clean-up and removal of arch prom.h headers. Makes arch specific
   prom.h optional on all but Sparc.
 - Addition of interrupts-extended property for devices connected to
   multiple interrupt controllers.
 - Refactoring of DT interrupt parsing code in preparation for deferred
   probe of interrupts.
 - ARM cpu and cpu topology bindings documentation.
 - Various DT vendor binding documentation updates.
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Merge tag 'devicetree-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull devicetree updates from Rob Herring:
 "DeviceTree updates for 3.13.  This is a bit larger pull request than
  usual for this cycle with lots of clean-up.

   - Cross arch clean-up and consolidation of early DT scanning code.
   - Clean-up and removal of arch prom.h headers.  Makes arch specific
     prom.h optional on all but Sparc.
   - Addition of interrupts-extended property for devices connected to
     multiple interrupt controllers.
   - Refactoring of DT interrupt parsing code in preparation for
     deferred probe of interrupts.
   - ARM cpu and cpu topology bindings documentation.
   - Various DT vendor binding documentation updates"

* tag 'devicetree-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (82 commits)
  powerpc: add missing explicit OF includes for ppc
  dt/irq: add empty of_irq_count for !OF_IRQ
  dt: disable self-tests for !OF_IRQ
  of: irq: Fix interrupt-map entry matching
  MIPS: Netlogic: replace early_init_devtree() call
  of: Add Panasonic Corporation vendor prefix
  of: Add Chunghwa Picture Tubes Ltd. vendor prefix
  of: Add AU Optronics Corporation vendor prefix
  of/irq: Fix potential buffer overflow
  of/irq: Fix bug in interrupt parsing refactor.
  of: set dma_mask to point to coherent_dma_mask
  of: add vendor prefix for PHYTEC Messtechnik GmbH
  DT: sort vendor-prefixes.txt
  of: Add vendor prefix for Cadence
  of: Add empty for_each_available_child_of_node() macro definition
  arm/versatile: Fix versatile irq specifications.
  of/irq: create interrupts-extended property
  microblaze/pci: Drop PowerPC-ism from irq parsing
  of/irq: Create of_irq_parse_and_map_pci() to consolidate arch code.
  of/irq: Use irq_of_parse_and_map()
  ...
2013-11-12 16:52:17 +09:00
Vineet Gupta
5ea72a9026 ARC: [SMP] TLB flush
- Add mm_cpumask setting (aggregating only, unlike some other arches)
  used to restrict the TLB flush cross-calling

- cross-calling versions of TLB flush routines (thanks to Noam)

Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06 10:41:45 +05:30
Vineet Gupta
63eca94ca2 ARC: [SMP] ASID allocation
-Track a Per CPU ASID counter
-mm-per-cpu ASID (multiple threads, or mm migrated around)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06 10:41:45 +05:30
Vineet Gupta
0a4c40a3b7 ARC: Fix bogus gcc warning and micro-optimise TLB iteration loop
------------------>8----------------------
arch/arc/mm/tlb.c: In function ‘do_tlb_overlap_fault’:
arch/arc/mm/tlb.c:688:13: warning: array subscript is above array bounds
[-Warray-bounds]
         (pd0[n] & PAGE_MASK)) {
             ^
------------------>8----------------------

While at it, remove the usless last iteration of outer loop when reading
a TLB SET for duplicate entries.

Suggested-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06 10:41:41 +05:30
Vineet Gupta
21a63b5604 ARC: Change calling convention of do_page_fault()
switch the args (address, pt_regs) to match with all the other "C"
exception handlers.

This removes the awkwardness in EV_ProtV for page fault vs. unaligned
access.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06 10:41:39 +05:30
Vineet Gupta
d4599baf5c ARC: cacheflush optim - PTAG can be loop invariant if V-P is const
Line op needs vaddr (indexing) and paddr (tag match). For page sized
flushes (V-P const), each line op will need a different index, but the
tag bits wil remain constant, hence paddr can be setup once outside the
loop.

This improves select LMBench numbers for Aliasing dcache where we have
more "preventive" cache flushing.

Processor, Processes - times in microseconds - smaller is better
------------------------------------------------------------------------------
Host                 OS  Mhz null null      open slct sig  sig  fork exec sh
                             call  I/O stat clos TCP  inst hndl proc proc proc
--------- ------------- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
3.11-rc7- Linux 3.11.0-   80 4.66 8.88 69.7 112. 268. 8.60 28.0 3489 13.K 27.K	# Non alias ARC700
3.11-rc7- Linux 3.11.0-   80 4.64 8.51 68.6 98.5 271. 8.58 28.1 4160 15.K 32.K	# Aliasing
3.11-rc7- Linux 3.11.0-   80 4.64 8.51 69.8 99.4 270. 8.73 27.5 3880 15.K 31.K	# PTAG loop Inv

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06 10:41:38 +05:30
Vineet Gupta
bd12976c36 ARC: cacheflush refactor #3: Unify the {d,i}cache flush leaf helpers
With Line length being constant now, we can fold the 2 helpers into 1.
This allows applying any optimizations (forthcoming) to single place.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06 10:41:38 +05:30
Vineet Gupta
63d2dfdbf4 ARC: cacheflush refactor #2: I and D caches lines to have same size
Having them be different seems an obscure configuration.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06 10:41:37 +05:30
Vineet Gupta
f3e4de3274 ARC: cacheflush refactor #1: push aux reg ascertaining into leaf routine
ARC dcache supports 3 ops - Inv, Flush, Flush-n-Inv.
The programming model however provides 2 commands FLUSH, INV.
INV will either discard or flush-n-discard (based on DT_CTRL bit)

The leaf helper __dc_line_loop() used to take the AUX register
(corresponding to the 2 commands). Now we push that to within the
helper, paving way for code consolidations to follow.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-11-06 10:41:29 +05:30
Vineet Gupta
9c41f4eeb9 ARC: Incorrect mm reference used in vmalloc fault handler
A vmalloc fault needs to sync up PGD/PTE entry from init_mm to current
task's "active_mm".  ARC vmalloc fault handler however was using mm.

A vmalloc fault for non user task context (actually pre-userland, from
init thread's open for /dev/console) caused the handler to deref NULL mm
(for mm->pgd)

The reasons it worked so far is amazing:

1. By default (!SMP), vmalloc fault handler uses a cached value of PGD.
   In SMP that MMU register is repurposed hence need for mm pointer deref.

2. In pre-3.12 SMP kernel, the problem triggering vmalloc didn't exist in
   pre-userland code path - it was introduced with commit 20bafb3d23
   "n_tty: Move buffers into n_tty_data"

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: stable@vger.kernel.org    #3.10 and 3.11
Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-02 10:27:04 -07:00
Rob Herring
29eb45a9ab of: remove early_init_dt_setup_initrd_arch
All arches do essentially the same thing now for
early_init_dt_setup_initrd_arch, so it can now be removed.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
2013-10-09 11:39:01 -05:00
Johannes Weiner
759496ba64 arch: mm: pass userspace fault flag to generic fault handler
Unlike global OOM handling, memory cgroup code will invoke the OOM killer
in any OOM situation because it has no way of telling faults occuring in
kernel context - which could be handled more gracefully - from
user-triggered faults.

Pass a flag that identifies faults originating in user space from the
architecture-specific fault handlers to generic code so that memcg OOM
handling can be improved.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: azurIt <azurit@pobox.sk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12 15:38:01 -07:00
Johannes Weiner
94bce453c7 arch: mm: remove obsolete init OOM protection
The memcg code can trap tasks in the context of the failing allocation
until an OOM situation is resolved.  They can hold all kinds of locks
(fs, mm) at this point, which makes it prone to deadlocking.

This series converts memcg OOM handling into a two step process that is
started in the charge context, but any waiting is done after the fault
stack is fully unwound.

Patches 1-4 prepare architecture handlers to support the new memcg
requirements, but in doing so they also remove old cruft and unify
out-of-memory behavior across architectures.

Patch 5 disables the memcg OOM handling for syscalls, readahead, kernel
faults, because they can gracefully unwind the stack with -ENOMEM.  OOM
handling is restricted to user triggered faults that have no other
option.

Patch 6 reworks memcg's hierarchical OOM locking to make it a little
more obvious wth is going on in there: reduce locked regions, rename
locking functions, reorder and document.

Patch 7 implements the two-part OOM handling such that tasks are never
trapped with the full charge stack in an OOM situation.

This patch:

Back before smart OOM killing, when faulting tasks were killed directly on
allocation failures, the arch-specific fault handlers needed special
protection for the init process.

Now that all fault handlers call into the generic OOM killer (see commit
609838cfed: "mm: invoke oom-killer from remaining unconverted page
fault handlers"), which already provides init protection, the
arch-specific leftovers can be removed.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: azurIt <azurit@pobox.sk>
Acked-by: Vineet Gupta <vgupta@synopsys.com>	[arch/arc bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12 15:38:01 -07:00
Linus Torvalds
31f7c3a688 Device tree core updates for v3.12
Generally minor changes. A bunch of bug fixes, particularly for
 initialization and some refactoring. Most notable change if feeding the
 entire flattened tree into the random pool at boot. May not be
 significant, but shouldn't hurt either.
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Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux

Pull device tree core updates from Grant Likely:
 "Generally minor changes.  A bunch of bug fixes, particularly for
  initialization and some refactoring.  Most notable change if feeding
  the entire flattened tree into the random pool at boot.  May not be
  significant, but shouldn't hurt either"

Tim Bird questions whether the boot time cost of the random feeding may
be noticeable.  And "add_device_randomness()" is definitely not some
speed deamon of a function.

* tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux:
  of/platform: add error reporting to of_amba_device_create()
  irq/of: Fix comment typo for irq_of_parse_and_map
  of: Feed entire flattened device tree into the random pool
  of/fdt: Clean up casting in unflattening path
  of/fdt: Remove duplicate memory clearing on FDT unflattening
  gpio: implement gpio-ranges binding document fix
  of: call __of_parse_phandle_with_args from of_parse_phandle
  of: introduce of_parse_phandle_with_fixed_args
  of: move of_parse_phandle()
  of: move documentation of of_parse_phandle_with_args
  of: Fix missing memory initialization on FDT unflattening
  of: consolidate definition of early_init_dt_alloc_memory_arch()
  of: Make of_get_phy_mode() return int i.s.o. const int
  include: dt-binding: input: create a DT header defining key codes.
  of/platform: Staticize of_platform_device_create_pdata()
  of: Specify initrd location using 64-bit
  dt: Typo fix
  OF: make of_property_for_each_{u32|string}() use parameters if OF is not enabled
2013-09-10 13:53:52 -07:00
Vineet Gupta
947bf103fc ARC: [ASID] Track ASID allocation cycles/generations
This helps remove asid-to-mm reverse map

While mm->context.id contains the ASID assigned to a process, our ASID
allocator also used asid_mm_map[] reverse map. In a new allocation
cycle (mm->ASID >= @asid_cache), the Round Robin ASID allocator used this
to check if new @asid_cache belonged to some mm2 (from prev cycle).
If so, it could locate that mm using the ASID reverse map, and mark that
mm as unallocated ASID, to force it to refresh at the time of switch_mm()

However, for SMP, the reverse map has to be maintained per CPU, so
becomes 2 dimensional, hence got rid of it.

With reverse map gone, it is NOT possible to reach out to current
assignee. So we track the ASID allocation generation/cycle and
on every switch_mm(), check if the current generation of CPU ASID is
same as mm's ASID; If not it is refreshed.

(Based loosely on arch/sh implementation)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-08-30 21:42:19 +05:30
Vineet Gupta
3daa48d1d9 ARC: [ASID] get_new_mmu_context() to conditionally allocate new ASID
ASID allocation changes/1

This patch does 2 things:

(1) get_new_mmu_context() NOW moves mm->ASID to a new value ONLY if it
    was from a prev allocation cycle/generation OR if mm had no ASID
    allocated (vs. before would unconditionally moving to a new ASID)

    Callers desiring unconditional update of ASID, e.g.local_flush_tlb_mm()
    (for parent's address space invalidation at fork) need to first force
    the parent to an unallocated ASID.

(2) get_new_mmu_context() always sets the MMU PID reg with unchanged/new
    ASID value.

The gains are:
- consolidation of all asid alloc logic into get_new_mmu_context()
- avoiding code duplication in switch_mm() for PID reg setting
- Enables future change to fold activate_mm() into switch_mm()

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-08-30 21:42:18 +05:30
Vineet Gupta
5bd87adf9b ARC: [ASID] Refactor the TLB paranoid debug code
-Asm code already has values of SW and HW ASID values, so they can be
 passed to the printing routine.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-08-30 21:42:18 +05:30