Not all PCI channels have non-translatable memory windows, this is a
special property of the on-chip PCIC with its 0xfd00... mapping, handle
this explicitly.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch changes the code to use __is_pci_memory() instead of
is_pci_memaddr(). __is_pci_memory() loops through all the pci
channels on the system to match memory windows.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This prevents the DMA API debugging from running out of entries right
away on boot. Defines 4096 entries by default, which while a bit on the
heavy side, ought to leave enough breathing room for some time.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Forcing direct-mapped worked on certain older 2-way set associative
parts, but was always error prone on 4-way parts. As these are the
norm these days, there is not much point in continuing to support this
mode. Most of the folks that used direct-mapped mode generally just
wanted writethrough caching in the first place..
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
While harmless, PTEA has different semantics on these parts, and is only
used in extended TLB mode. Kill off the legacy support.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds support for extended ASIDs (up to 16-bits) on newer SH-X3 cores
that implement the PTAEX register and respective functionality. Presently
only the 65nm SH7786 (90nm only supports legacy 8-bit ASIDs).
The main change is in how the PTE is written out when loading the entry
in to the TLB, as well as in how the TLB entry is selectively flushed.
While SH-X2 extended mode splits out the memory-mapped U and I-TLB data
arrays for extra bits, extended ASID mode splits out the address arrays.
While we don't use the memory-mapped data array access, the address
array accesses are necessary for selective TLB flushes, so these are
implemented newly and replace the generic SH-4 implementation.
With this, TLB flushes in switch_mm() are almost non-existent on newer
parts.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements preliminary suspend/resume support for the PMB.
Signed-off-by: Francesco Virlinzi <francesco.virlinzi@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This provides a method for supporting fixed PMB mappings inherited from
the bootloader, as an alternative to the dynamic PMB mapping currently
used by the kernel. In the future these methods will be combined.
P1/P2 area is handled like a regular 29-bit physical address, and local
bus device are assigned P3 area addresses.
Signed-off-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Fix iounmap() of pass-through P4 addresses. Without this patch
iounmap() on the sh7780 rtc area results in a warning message.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
If the NULL test is necessary, then the dereference should be moved below
the NULL test.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/).
// <smpl>
@disable is_null@
identifier f;
expression E;
identifier fld;
statement S;
@@
+ if (E == NULL) S
f(...,E->fld,...);
- if (E == NULL) S
@@
identifier f;
expression E;
identifier fld;
statement S;
@@
+ if (!E) S
f(...,E->fld,...);
- if (!E) S
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Show node to memory section relationship with symlinks in sysfs
Add /sys/devices/system/node/nodeX/memoryY symlinks for all
the memory sections located on nodeX. For example:
/sys/devices/system/node/node1/memory135 -> ../../memory/memory135
indicates that memory section 135 resides on node1.
Also revises documentation to cover this change as well as updating
Documentation/ABI/testing/sysfs-devices-memory to include descriptions
of memory hotremove files 'phys_device', 'phys_index', and 'state'
that were previously not described there.
In addition to it always being a good policy to provide users with
the maximum possible amount of physical location information for
resources that can be hot-added and/or hot-removed, the following
are some (but likely not all) of the user benefits provided by
this change.
Immediate:
- Provides information needed to determine the specific node
on which a defective DIMM is located. This will reduce system
downtime when the node or defective DIMM is swapped out.
- Prevents unintended onlining of a memory section that was
previously offlined due to a defective DIMM. This could happen
during node hot-add when the user or node hot-add assist script
onlines _all_ offlined sections due to user or script inability
to identify the specific memory sections located on the hot-added
node. The consequences of reintroducing the defective memory
could be ugly.
- Provides information needed to vary the amount and distribution
of memory on specific nodes for testing or debugging purposes.
Future:
- Will provide information needed to identify the memory
sections that need to be offlined prior to physical removal
of a specific node.
Symlink creation during boot was tested on 2-node x86_64, 2-node
ppc64, and 2-node ia64 systems. Symlink creation during physical
memory hot-add tested on a 2-node x86_64 system.
Signed-off-by: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Split pages returned by dma_alloc_coherent() and make sure
we free them one by one.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This migrates from the old bitrotted kgdb stub implementation and moves
to the generic stub. In the process support for SH-2/SH-2A is also added,
which the old stub never provided.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This converts the sh64 /proc/asids entry to debugfs and enables it for
all SH parts that have debugfs enabled.
On MMU systems this can be used to determine which processes are using
which ASIDs which in turn can be used for finer grained cache tag
analysis.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch adds a pass-through case when ioremapping P4 addresses.
Addresses passed to ioremap() should be physical addresses, so the
best option is usually to convert the virtual address to a physical
address before calling ioremap. This will give you a virtual address
in P2 which matches the physical address and this works well for
most internal hardware blocks on the SuperH architecture.
However, some hardware blocks must be accessed through P4. Converting
the P4 address to a physical and then back to a P2 does not work. One
example of this is the sh7722 TMU block, it must be accessed through P4.
Without this patch P4 addresses will be mapped using PTEs which
requires the page allocator to be up and running.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
With the PMB enabled, only P1SEG and up are covered by the PMB mappings,
meaning that situations where out-of-bounds physical addresses are read
from will lead to TLB reset after the PMB miss, allowing for use cases
like dd if=/dev/mem to reset the TLB.
Fix this up to make sure the reference is between __MEMORY_START (phys)
and __pa(high_memory). This is coherent across all variants of sh/sh64
with and without MMU, though the PMB bug itself is only applicable to
SH-4A parts.
Reported-by: Hideo Saito <saito@densan.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There was a race in the kmap_coherent() implementation. While we
guarded against preemption, there was nothing preventing eviction of
the pre-faulted fixmap entry from the UTLB. Under certain workloads
this would result in the fixmap entries used for cache colouring being
evicted from the UTLB in the midst of a copy_page().
In addition to pre-faulting, we also make sure to preserve the PTEs
in the kernel page table and introduce a cached PTE for kmap_coherent()
usage. This follows a similar change on MIPS ("[MIPS] Fix aliasing bug
in copy_to_user_page / copy_from_user_page").
Reported-by: Hideo Saito <saito@densan.co.jp>
Reported-by: CHIKAMA Masaki <masaki.chikama@gmail.com>
Tested-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Use the generic remove_memory() provided by mm/memory_hotplug.c instead.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Remove left overs from the generic declared coherent rework.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
debugfs_create_file() returns NULL if an error occurs, returns -ENODEV
when debugfs is not enabled in the kernel.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements a few trace points across events that are deemed
interesting. This implements a number of trace points:
- The page fault handler / TLB miss
- IPC calls
- Kernel thread creation
The original LTTng patch had the slow-path instrumented, which
fails to account for the vast majority of events. In general
placing this in the fast-path is not a huge performance hit, as
we don't take page faults for kernel addresses.
The other bits of interest are some of the other trap handlers, as
well as the syscall entry/exit (which is better off being handled
through the tracehook API). Most of the other trap handlers are corner
cases where alternate means of notification exist, so there is little
value in placing extra trace points in these locations.
Based on top of the points provided both by the LTTng instrumentation
patch as well as the patch shipping in the ST-Linux tree, albeit in a
stripped down form.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This follows the powerpc commit f6a616800e
'[POWERPC] Fix kernel stack allocation alignment'.
SH has traditionally forced the thread order to be relative to the page
size, so there were never any situations where the same bug was
triggered by slub. Regardless, the usage of > 8kB stacks for the larger
page sizes is overkill, so we switch to using slab allocations there,
as per the powerpc change.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This uses jump_to_uncached() which is now given the noinline attribute
due to the special section mapping. Kill off the inline attribute to
fix up compilation failure.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Because alloc_bootmem functions return the allocated memory always
zeroed, an additional call of memset on allocated memory is
unnecessary.
Signed-off-by: Marek Skuczynski <M.Skuczynski@adbglobal.com>
Signed-off-by: Carl Shaw <carl.shaw@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This fixes a problem in the code which copies the vmalloc portion of the
kernel's page table into the current user space page table. The addition
of the four level page table code breaks on folded page tables, because
the pud level is always present (although folded). This updates the code
to use the same style of updates for the pud as is used for the pgd
level.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
statically initialise the cached_to_uncached offset, so that we can use
it immediatly.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch kills a section mismatch for platform_resource_setup_memory().
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Allow user to pass parameters on kernel command line to override
default size for physically contiguous memory buffers. The default
VPU buffer size is too small for VGA harware encoding, but instead
of just bumping up the number we allow the user to override the
default size using the command line. Supports SuperH Mobile hardware
blocks such as VEU, VPU and CEU.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Presently we oops in mm/hugetlb.c:1325, which is the order == 0 test in
hugetlb_add_hstate() called at initialization time. So, disable 64kB
huge pages when we're using a 64kB PAGE_SIZE. On most parts this will
force the default to be 1MB huge pages.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (28 commits)
mm/hugetlb.c must #include <asm/io.h>
video: Fix up hp6xx driver build regressions.
sh: defconfig updates.
sh: Kill off stray mach-rsk7203 reference.
serial: sh-sci: Fix up SH7760/SH7780/SH7785 early printk regression.
sh: Move out individual boards without mach groups.
sh: Make sure AT_SYSINFO_EHDR is exposed to userspace in asm/auxvec.h.
sh: Allow SH-3 and SH-5 to use common headers.
sh: Provide common CPU headers, prune the SH-2 and SH-2A directories.
sh/maple: clean maple bus code
sh: More header path fixups for mach dir refactoring.
sh: Move out the solution engine headers to arch/sh/include/mach-se/
sh: I2C fix for AP325RXA and Migo-R
sh: Shuffle the board directories in to mach groups.
sh: dma-sh: Fix up dreamcast dma.h mach path.
sh: Switch KBUILD_DEFCONFIG to shx3_defconfig.
sh: Add ARCH_DEFCONFIG entries for sh and sh64.
sh: Fix compile error of Solution Engine
sh: Proper __put_user_asm() size mismatch fix.
sh: Stub in a dummy ENTRY_OFFSET for uImage offset calculation.
...
This follows the sparc changes a439fe51a1.
Most of the moving about was done with Sam's directions at:
http://marc.info/?l=linux-sh&m=121724823706062&w=2
with subsequent hacking and fixups entirely my fault.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
fix the problem that cannot boot using uImage when PAGE_SIZE is
8kbyte or 64kbyte.
Signed-off-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Commit 1ea0704e0d
(mm: add a ptep_modify_prot transaction abstraction)
triggered on sh build errors like the following:
<-- snip -->
...
CC arch/sh/mm/pg-sh4.o
cc1: warnings being treated as errors
include2/asm/pgtable.h:139: error: 'ptep_get_and_clear' declared inline after being called
include2/asm/pgtable.h:139: error: previous declaration of 'ptep_get_and_clear' was here
make[2]: *** [arch/sh/mm/pg-sh4.o] Error 1
<-- snip -->
Since there's no good reason for marking these global functions as
"inline" this patch therefore removes the inline's.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch adds physically contiguous memory chunks to the UIO devices.
The same strategy can be used in the future for the CEU as well.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Remove inline from ptep_get_and_clean() to match with header file prototype.
Makes linux-next build.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The current kernel behaviour is to reenable interrupts unconditionally
when taking a page fault. This patch changes this to only enable them
if interrupts were previously enabled.
It also fixes a problem seen with this fix in place: the kernel previously
flushed the vsyscall page when handling a signal, which is not only
unncessary, but caused a possible sleep with interrupts disabled.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add implementation of flush_icache_range() suitable for signal handler
and kprobes. Remove flush_cache_sigtramp() and change signal.c to use
flush_icache_range().
Signed-off-by: Chris Smith <chris.smith@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
16kB is a useful size on nommu, while 64kB still tends to be too big to
be useful. Newer MMUs are likely to support this as well, so plug it
in in anticipation of those, too.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
PAGE_SIZE doesn't need to be fixed at 4096 on nommu, so stub in a !MMU
case for the various PAGE_SIZE Kconfig options.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
When using single_open(), single_release() should be used instead
of seq_release(), otherwise there is a memory leak.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Remove arch-specific show_mem() in favor of the generic version.
This also removes the following redundant information display:
- free pages, printed by show_free_areas()
- pages in slab, printed by show_free_areas()
- free swap pages, printed by show_swap_cache_info()
- pages in swapcache, printed by show_swap_cache_info()
where show_mem() calls show_free_areas(), which calls
show_swap_cache_info().
Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kmem cache passed to constructor is only needed for constructors that are
themselves multiplexeres. Nobody uses this "feature", nor does anybody uses
passed kmem cache in non-trivial way, so pass only pointer to object.
Non-trivial places are:
arch/powerpc/mm/init_64.c
arch/powerpc/mm/hugetlbpage.c
This is flag day, yes.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Jon Tollefson <kniht@linux.vnet.ibm.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Matt Mackall <mpm@selenic.com>
[akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c]
[akpm@linux-foundation.org: fix mm/slab.c]
[akpm@linux-foundation.org: fix ubifs]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Almost all users of this field need a PFN instead of a physical address,
so replace node_boot_start with node_min_pfn.
[Lee.Schermerhorn@hp.com: fix spurious BUG_ON() in mark_bootmem()]
Signed-off-by: Johannes Weiner <hannes@saeureba.de>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Straight forward extensions for huge pages located in the PUD instead of
PMDs.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The goal of this patchset is to support multiple hugetlb page sizes. This
is achieved by introducing a new struct hstate structure, which
encapsulates the important hugetlb state and constants (eg. huge page
size, number of huge pages currently allocated, etc).
The hstate structure is then passed around the code which requires these
fields, they will do the right thing regardless of the exact hstate they
are operating on.
This patch adds the hstate structure, with a single global instance of it
(default_hstate), and does the basic work of converting hugetlb to use the
hstate.
Future patches will add more hstate structures to allow for different
hugetlbfs mounts to have different page sizes.
[akpm@linux-foundation.org: coding-style fixes]
Acked-by: Adam Litke <agl@us.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are a lot of places that define either a single bootmem descriptor or an
array of them. Use only one central array with MAX_NUMNODES items instead.
Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Kyle McMartin <kyle@parisc-linux.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add physical memory resources such as System RAM, Kernel code/data/bss
and reserved crash dump area to /proc/iomem. Same strategy as on x86.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
All architectures use an effectively identical definition of online_page(), so
just make it common code. x86-64, ia64, powerpc and sh are actually
identical; x86-32 is slightly different.
x86-32's differences arise because it puts its hotplug pages in the highmem
zone. We can handle this in the generic code by inspecting the page to see if
its in highmem, and update the totalhigh_pages count appropriately. This
leaves init_32.c:free_new_highpage with a single caller, so I folded it into
add_one_highpage_init.
I also removed an incorrect comment referring to the NUMA case; any NUMA
details have already been dealt with by the time online_page() is called.
[akpm@linux-foundation.org: fix indenting]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamez.hiroyu@jp.fujitsu.com>
Tested-by: KAMEZAWA Hiroyuki <kamez.hiroyu@jp.fujitsu.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Christoph Lameter <clameter@sgi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There's still work that needs to be done here, and this should not be
enabled by default on existing boards.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch fixes the following compile error:
<-- snip -->
...
CC arch/sh/mm/pg-sh7705.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/sh/mm/pg-sh7705.c: In function 'ptep_get_and_clear':
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/sh/mm/pg-sh7705.c:130: error: implicit declaration of function 'mapping_writably_mapped'
make[2]: *** [arch/sh/mm/pg-sh7705.o] Error 1
<-- snip -->
Signed-off-by: Adrian Bunk <adrian.bunk@movial.fi>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This acts as a reversion of 1c6b2ca5e0 in
the case of UP SH-4, where we still have the risk of a multiple hit
between the slow and fast paths. As seen on SH7780.
Signed-off-by: Hideo Saito <saito@densan.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Previously this took an explicit range, update this to use the same
behaviour as the rest of the SH parts where we simply flush out a line
from the start address.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The idea is that we want to get rid of the in/out/readb/writeb callbacks from
the machvec and replace that with simple inline read and write operations to
memory. Fast and simple for most hardware devices (think pci).
Some devices require special treatment though - like 16-bit only CF devices -
so we need to have some method to hook in callbacks.
This patch makes it possible to add a per-device trap generating filter. This
way we can get maximum performance of sane hardware - which doesn't need this
filter - and crappy hardware works but gets punished by a performance hit.
V2 changes things around a bit and replaces io access callbacks with a
simple minimum_bus_width value. In the future we can add stride as well.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch fixes the recently introduced declared coherent memory support.
Without this fix a cached memory area is returned by dma_alloc_coherent() -
unless dma_declare_coherent_memory() has setup a separate area.
This patch makes sure an uncached memory area is returned. With this patch
it is now possible to ping through an rtl8139 interface on r2d-plus.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patchset adds a flags variable to reserve_bootmem() and uses the
BOOTMEM_EXCLUSIVE flag in crashkernel reservation code to detect collisions
between crashkernel area and already used memory.
This patch:
Change the reserve_bootmem() function to accept a new flag BOOTMEM_EXCLUSIVE.
If that flag is set, the function returns with -EBUSY if the memory already
has been reserved in the past. This is to avoid conflicts.
Because that code runs before SMP initialisation, there's no race condition
inside reserve_bootmem_core().
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds declared coherent memory support to the sh architecture. All
functions are based on the x86 implementation. Header files are adjusted to
use the new functions instead of the former consistent_alloc() code.
This version includes the few changes what were included in the fix patch
together with modifications based on feedback from Paul.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This saves us from having to use kmalloc() for the fixmap entries,
which is needed early for the uncached fixmap.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Presently most of the 29-bit physical parts do P1/P2 segmentation
with a 1:1 cached/uncached mapping, jumping between the two to
control the caching behaviour. This provides the basic infrastructure
to maintain this behaviour on 32-bit physical parts that don't map
P1/P2 at all, using a shiny new linker section and corresponding
fixmap entry.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
With the refactored update_mmu_cache() introduced in older kernels,
there's no longer any need to take the page_table_lock in this path,
so simply drop it completely.
Without this, performance degradation is seen on SMP on heavily
threaded workloads that don't use the split ptlock, and ultimately
we have no reason to contend for the lock in the first place.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The __do_page_fault() fast-path contains a UTLB flush in order to
force an ITLB reload, this isn't needed in practice as the ITLB is
auto-reloaded from the UTLB anyways, which is already displaced by
the manual 'ldtlb' in the update_mmu_cache() path.
This provides a measurable speed up in the TLB miss fast-path.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Now that copy_to_user_page()/copy_from_user_page() are wired up, we
can drop the old __copy_xxx() implementations. Now that the page
colouring scheme has changed via kmap_coherent(), we can avoid the
flush in these specific helpers.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This moves copy_{to,from}_user_page() out-of-line on SH-4 and
converts for the kmap_coherent() API. Based on the MIPS
implementation.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
With the kmap_coherent() API in place, this is trivial to implement,
and lets us avoid the cache flush in certain cases.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The ST40 stuff in-tree hasn't built for some time, and hasn't been
updated for over 3 years. ST maintains their own out-of-tree changes
and rebases occasionally, and that's ultimately where all of the ST40
users go anyways.
In order for the ST40 code to be brought up to date most of the stuff
removed in this changeset would have to be rewritten anyways, so there's
very little benefit in keeping the remnants around either.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
movca.l is restricted to SH-4 and up only, though compilers that
are unable to support ISA tuning (especially older versions of
binutils) will happily compile in the bogus opcode on older parts.
Conditionalize it to fix SH-3 regressions noted by Kristoffer.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
is_init() is an ambiguous name for the pid==1 check. Split it into
is_global_init() and is_container_init().
A cgroup init has it's tsk->pid == 1.
A global init also has it's tsk->pid == 1 and it's active pid namespace
is the init_pid_ns. But rather than check the active pid namespace,
compare the task structure with 'init_pid_ns.child_reaper', which is
initialized during boot to the /sbin/init process and never changes.
Changelog:
2.6.22-rc4-mm2-pidns1:
- Use 'init_pid_ns.child_reaper' to determine if a given task is the
global init (/sbin/init) process. This would improve performance
and remove dependence on the task_pid().
2.6.21-mm2-pidns2:
- [Sukadev Bhattiprolu] Changed is_container_init() calls in {powerpc,
ppc,avr32}/traps.c for the _exception() call to is_global_init().
This way, we kill only the cgroup if the cgroup's init has a
bug rather than force a kernel panic.
[akpm@linux-foundation.org: fix comment]
[sukadev@us.ibm.com: Use is_global_init() in arch/m32r/mm/fault.c]
[bunk@stusta.de: kernel/pid.c: remove unused exports]
[sukadev@us.ibm.com: Fix capability.c to work with threaded init]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Acked-by: Pavel Emelianov <xemul@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Herbert Poetzel <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dma_cache_(wback|inv|wback_inv) were the earliest attempt on a generalized
cache managment API for I/O purposes. Originally it was basically the raw
MIPS low level cache API exported to the entire world. The API has
suffered from a lack of documentation, was not very widely used unlike it's
more modern brothers and can easily be replaced by dma_cache_sync. So
remove it rsp. turn the surviving bits back into an arch private API, as
discussed on linux-arch.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Slab constructors currently have a flags parameter that is never used. And
the order of the arguments is opposite to other slab functions. The object
pointer is placed before the kmem_cache pointer.
Convert
ctor(void *object, struct kmem_cache *s, unsigned long flags)
to
ctor(struct kmem_cache *s, void *object)
throughout the kernel
[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now, arch dependent code around CONFIG_MEMORY_HOTREMOVE is a mess.
This patch cleans up them. This is against 2.6.23-rc6-mm1.
- fix compile failure on ia64/ CONFIG_MEMORY_HOTPLUG && !CONFIG_MEMORY_HOTREMOVE case.
- For !CONFIG_MEMORY_HOTREMOVE, add generic no-op remove_memory(),
which returns -EINVAL.
- removed remove_pages() only used in powerpc.
- removed no-op remove_memory() in i386, sh, sparc64, x86_64.
- only powerpc returns -ENOSYS at memory hot remove(no-op). changes it
to return -EINVAL.
Note:
Currently, only ia64 supports CONFIG_MEMORY_HOTREMOVE. I welcome other
archs if there are requirements and testers.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have had complaints where a threaded application is left in a bad state
after one of it's threads is killed when we hit a VM: out_of_memory
condition.
Killing just one of the process threads can leave the application in a bad
state, whereas killing the entire process group would allow for the
application to restart, or be otherwise handled, and makes it very obvious
that something has gone wrong.
This change allows the entire process group to be taken down, rather
than just the one thread.
Signed-off-by: Will Schmidt <will_schmidt@vnet.ibm.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This implements a fast-path for small (less than 12 bytes) copies,
with the existing path treated as the slow-path and left as the default
behaviour for all other copy sizes.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
When using URAM in NUMA mode another active region is needed.
Bump this up so we don't trigger the region truncation in
add_active_range().
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
4kB pages are unstable on extended mode TLB, it's recommended
that TLB compat mode be used when using a 4kB PAGE_SIZE. Set
the default for extended mode to 8kB.
This should have negligible impact, as other than the extra swap
cache entry bits, there's no reason to use the extended mode TLB
with 4kB pages.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Calculate the number of cache aliases on probed L2 caches, and while
we're at it, print out the detected statistics at boot time for these
also.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
We stopped referencing these functions unconditionally when the
old entry.S code was refactored, so this is just dead code at
present. Kill it off.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There was an off-by-1 on the cache alias detection logic on SH-4,
which caused n_aliases to always be 1 even when the page size
precluded the existence of aliases.
With this corrected, 64KB pages happily reports n_aliases == 0, and
hits the appropriate fast paths in the flushing routines.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds basic support for SH-X3 SMP (4 CPUs).
More IPI and cache debugging is necessary, mostly interfacing the
d-cache coherency and the I-cache broadcast invalidates. Only for
testing at present!
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
current_cpu_data uses smp_processor_id() in order to find the
corresponding cpu_data. As the cache descs are all currently
identical, just have this look at probed results from the boot
CPU.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The extended mode TLB requires both 64-bit PTEs and a 64-bit pgprot,
correspondingly, the PGD also has to be 64-bits, so fix that up.
The kernel and user permission bits really are decoupled in early
cuts of the silicon, which means that we also have to set corresponding
kernel permissions on user pages or we end up with user pages that the
kernel simply can't touch (!).
Finally, with those things corrected, really enable MMUCR.ME and
correct the PTEA value (this simply needs to be the upper 32-bits
of the PTE, with the size and protection bit encoding).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This leads to invalid configurations where both FPU and DSP support
can be enabled in the same kernel, resulting in build failure.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch contains the following fixes:
- Adds sh7785 support to CONFIG_EARLY_SCIF_CONSOLE_PORT.
- Removes duplicate include from rts7751r2d irq code.
- Removes CONFIG_CPU_HAS_INTC from sh7720 Kconfig entry.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
All processor specific interrupt code is now converted to make use
of the new intc code. The config option CONFIG_CPU_HAS_INTC_IRQ is
because of that pointless.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific interrupt setup code for sh7206
from ipr to intc. New vectors are also added to match the information
provided by the datasheet.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific interrupt setup code for sh7619
from ipr to intc. New vectors are also added to match the information
provided by the datasheet.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds support for the SH7720 (SH3-DSP) CPU.
Signed-off by: Markus Brunner <super.firetwister@gmail.com>
Signed-off by: Mark Jonas <toertel@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There is no point in keeping around the now unused intc2 code.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific interrupt setup code for x3 from
intc2 to intc. New vectors are also added to match the preliminary
information.
Use plat_irq_setup_pins() to select between IRQ and IRL mode for IRQ0-3.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific interrupt setup code for sh7760
from ipr + intc2 to intc. New vectors are also added to match the
information provided by the datasheet.
Vectors for IRQ4-IRQ7 are enabled by default. Use plat_irq_setup_pins()
if pins IRL0-3 should be used in IRLM mode.
The patch also adds the SIM block to the serial port platform data.
Version two of this patch fixes MMCIF problems reported by Manuel Lauss.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific interrupt setup code for sh7785
from intc2 to intc. New vectors are also added to match the information
provided by the datasheet.
No IRQ/IRL pin vectors are enabled by default. Use plat_irq_setup_pins()
to select between IRL and IRQ mode.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This reworks the cache mode configuration in Kconfig, and allows for
explicit selection of write-back/write-through/off configurations.
All of the cache flushing routines are optimized away for the off
case.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch unifies the cpu specific interrupt setup code for
sh7706, sh7707, sh7708 and sh7709 and moves the code into a new
file called setup-sh770x.c. It makes sense to share the setup code
between these processors because most hardware blocks are identical
from a software point of view. With this patch the sh770x processors
now have a complete set of vectors that match with the information
provided by the data sheets. This is a big improvement for sh7708.
Vectors for IRQ4 and IRQ5 are enabled by default. Use
plat_irq_setup_pins() if pins IRQ0-3 should be used in IRQ mode.
This patch also unifies the platform device setup code which means
that the rtc driver now has platform data for all sh770x processors.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific interrupt setup code
for sh7710 from ipr to intc. While at it new vectors are added
to match the information provided by the datasheet. Version two
simplifies the Kconfig part.
Vectors for IRQ4 and IRQ5 are enabled by default. Use
plat_irq_setup_pins() if pins IRQ0-3 should be used in IRQ mode.
This patch also adds sh7710 specific platform data for the rtc
driver. The base address of SCIF1 is adjusted to match the
datasheet.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific interrupt setup code for
sh7705 from ipr to intc. While at it new vectors are added to
match the information provided by the datasheet.
Vectors for IRQ4 and IRQ5 are enabled by default.
Use plat_irq_setup_pins() if pins IRQ0-3 should be used in IRQ mode.
This patch also adds sh7705 specific platform data for the rtc driver.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
When reading the cached TTB value and extracting the pgd, we
accidentally applied a __va() to it and bumped it off in to bogus
space which ended up causing multiple faults in the error path.
Fix it up so unhandled faults don't do strange and highly unorthodox
things when oopsing.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
fault-nommu defines the page fault handler stubs for SH-3/4 parts,
but is not needed on SH-2/SH-2A now that the entry code has been
logically separated.
Add it in for SH-3 and SH-4 explicitly.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
We were missing the trace_hardirqs_on() instrumentation in the nommu
case, resync with the MMU version of the page fault handler to have
this behaving consistently. Also explicitly re-enable IRQs now that
the assembly code isn't doing it for us any more.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch removes old dead code:
- kill off sh7300 cpu support
- get rid of broken solution engine 7300 board support
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Not all CPUs support the DSP, and this leads to problems when mixing
and matching CPU types and DSP opcodes. Fix this up by only allowing
CONFIG_SH_DSP to be enabled for the CPUs that explicitly have such a
block.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch removes old dead code:
- kill off sh73180 cpu support
- get rid of broken solution engine 73180 board support
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The code in arch/sh/kernel/cpu/irq/pint.c doesn't compile, so let's
get rid of it to make space for a future pint implementation on top
of intc.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The first 1MB of P3 space was reserved and used for page colouring,
as we've reworked that to use fixmaps, we can reclaim the space and
hand it back to VMALLOC_START.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This wires up kmap_coherent() and kunmap_coherent() on SH-4, and
moves away from the p3map_mutex and reserved P3 space, opting to
use fixmaps for colouring instead.
The copy_user_page()/clear_user_page() implementations are moved
to this, which fixes the nasty blowups with spinlock debugging
as a result of having some of these calls nested under the page
table lock.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific 7750 setup code to use the
new intc controller. Many new vectors are added and multiple
processor variants including 7091, 7750, 7750s, 7750r, 7751 and
7751r should all have the correct vectors hooked up.
IRLM interrupts can be enabled using ipr_irq_enable_irlm() which
now is marked as __init.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific 7780 setup code to use the
new intc controller. Many new vectors are added and also support for
external interrupt sense configuration. So with this patch it is now
possible to configure external interrupt pins as edge or level
triggered using set_irq_type().
No external interrupts are registered by default.
Use plat_irq_setup_pins() to select between IRQ or IRL mode.
This patch also fixes the Alarm IRQ for the RTC.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch converts the cpu specific 7722 setup code to use the
new intc controller. Many new vectors are added and also support
for external interrupt sense configuration. So with this patch
it is now possible to configure external interrupt pins as edge
or level triggered using set_irq_type().
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.
This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch completes Linus's wish that the fault return codes be made into
bit flags, which I agree makes everything nicer. This requires requires
all handle_mm_fault callers to be modified (possibly the modifications
should go further and do things like fault accounting in handle_mm_fault --
however that would be for another patch).
[akpm@linux-foundation.org: fix alpha build]
[akpm@linux-foundation.org: fix s390 build]
[akpm@linux-foundation.org: fix sparc build]
[akpm@linux-foundation.org: fix sparc64 build]
[akpm@linux-foundation.org: fix ia64 build]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Still apparently needs some ARM and PPC loving - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Only print out pgd/pte data in the oops path if oops_may_print()
holds true. Follows the i386 implementation.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
We don't have a PMB for SH-X2 or later, so only enable it for
the few CPUs that support it. Fixes up the boot for SH4AL-DSP.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There's no point in keeping these around, they've been broken
for some time, and the dmaenging/async_tx framework provides a
far more reasonable interface.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
SH-2 can presently get in to some pretty bogus states, so
we tidy up the dependencies a bit and get it all building
again.
This gets us a bit closer to a functional allyesconfig
and allmodconfig, though there are still a few things to
fix up.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This was added during 2.5.x, but was never moved along. This
can easily be resurrected if someone has one they wish to work
with, but it's not worth keeping around in its current form.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This enables simple hotplug support for sparsemem users. Presently
this only permits memory being added in to node 0 on ZONE_NORMAL.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds the URAM block on SH7722 as a separate node.
Sparsemem is required for this, or it can simply be disabled
by explicitly selecting a flatmem model.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds basic support for multiple nodes on SH machines.
This is primarily useful for boards with many different
memory blocks that are otherwise unused (SH7722/SH7785 URAM
and so forth).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Currently using multiple nodes tramples the ZONE_NORMAL
max low pfn, tidy up the logic a bit to get it all working
as expected.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements basic sparsemem support for SH. Presently this only
uses static sparsemem, and we still permit explicit selection of
flatmem. Those boards that want sparsemem can select it as usual.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Now that select no longer works for selecting the "closest" CPU,
we have to explicitly reference the precise sub-type in the few
places where it actually matters (presently only setup code and
some legacy sh-sci cruft).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This was a big mess, rework the logic a bit so that we constrain
to a particular subtype and figure out the board support based
on that. This makes building subtype specific kernels supporting
multiple boards possible again.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
SH-3 comes up with the PAGE_SIZE on a misaligned boundary:
arch/sh/mm/copy_page.S: Assembler messages:
arch/sh/mm/copy_page.S:132: Warning: misaligned data
fix it up with explicit alignment.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
- setup-sh7750.c only defines the sh7751_ipr_map when building
with SH7751 support.
- 7722 Solution Engine was missing a mach-type entry, causing
the macro in cf-enabler to be undefined.
- arch/sh/mm/init.c needs linux/pagemap.h.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Just at the time you added them on sh we're removing them from other
architectures. As there's no user yet this patch just removes them
completely. Once you actually have a kprobes patch it should follow
the direct call to kprobes_fault_handler model that powerpc, s390 and
sparc64 employ in 2.6.22-rc1 and that I'm updating other architectures
to.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This is the last remaining slab destructor in the kernel, which
we kill off and move the resultant list tracking logic up to
the pmb_alloc()/pmb_free() paths.
As Christoph Lameter pointed out, it's potentially unsafe to be
taking the list lock in the destructor anyways, so this is also
more fundamentally correct.
With this in place, we're all set for killing off slab destructors
from the kernel entirely.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
GCC doesn't seem to be able to figure this one out for
itself, so just shut it up..
CC arch/sh/mm/fault.o
arch/sh/mm/fault.c: In function '__do_page_fault':
arch/sh/mm/fault.c:288: warning: 'ptl' may be used uninitialized in this function
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Most SH platforms aren't going to need more than a single active
region, ones that need more can pad this out as necessary.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This moves SH over to the generic quicklists. As per x86_64,
we have special mappings for the PGDs, so these go on their
own list..
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use SLAB_PANIC and delete duplicated panic().
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Ian Molton <spyro@f2s.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes up SH7705 CPU support and the SE7705 board
for some of the recent changes.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.zh@hitachi.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This reworks some of the node 0 bootmem initialization in
preparation for discontigmem and sparsemem support.
ARCH_POPULATES_NODE_MAP is switched to as a result of this.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This ended up causing problems for older parts (particularly ones
using PTEA). Revert this for now, it can be added back in once it's
had some more testing.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Convert some of the global flush users over to using the local variants
that don't need to use the global routines.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Rename the existing flush routines to local_ variants for use by
the IPI-backed global flush routines on SMP.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There are a lot of bogus cpu_data-> references that only end up working
for the boot CPU, convert these to current_cpu_data to fixup SMP.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Previously this was implemented using a global cache, cache
this per-CPU instead and bump up the number of context IDs to
match NR_CPUS.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Only SH-4 needs to set _PAGE_WT when using write-through caching,
don't attempt to set it on SH-3 where it ends up being a reserved
bit.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This converts the lazy dcache handling to the model described in
Documentation/cachetlb.txt and drops the ptep_get_and_clear() hacks
used for the aliasing dcaches on SH-4 and SH7705 in 32kB mode. As a
bonus, this slightly cuts down on the cache flushing frequency.
With that and the PTEA handling out of the way, the update_mmu_cache()
implementations can be consolidated, and we no longer have to worry
about which configuration the cache is in for the SH7705 case.
And finally, explicitly disable the lazy writeback on SMP (SH-4A).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This fixes up shmin (and SH7706/SH7708) IPR support for some of the
recent API changes.
Signed-off-by: Takashi YOSHII <takasi-y@ops.dti.ne.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
[akpm@osdl.org: sparc64 fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sh / sh64: Remove ZONE_DMA remains.
Both arches do not need ZONE_DMA
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert SH to use generic ioremap_page_range()
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Replace all uses of kmem_cache_t with struct kmem_cache.
The patch was generated using the following script:
#!/bin/sh
#
# Replace one string by another in all the kernel sources.
#
set -e
for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
quilt add $file
sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
mv /tmp/$$ $file
quilt refresh
done
The script was run like this
sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Following up with the work on shared page table done by Dave McCracken. This
set of patch target shared page table for hugetlb memory only.
The shared page table is particular useful in the situation of large number of
independent processes sharing large shared memory segments. In the normal
page case, the amount of memory saved from process' page table is quite
significant. For hugetlb, the saving on page table memory is not the primary
objective (as hugetlb itself already cuts down page table overhead
significantly), instead, the purpose of using shared page table on hugetlb is
to allow faster TLB refill and smaller cache pollution upon TLB miss.
With PT sharing, pte entries are shared among hundreds of processes, the cache
consumption used by all the page table is smaller and in return, application
gets much higher cache hit ratio. One other effect is that cache hit ratio
with hardware page walker hitting on pte in cache will be higher and this
helps to reduce tlb miss latency. These two effects contribute to higher
application performance.
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: Dave McCracken <dmccr@us.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following moves the creation of IPR interupts into setup-7750.c
and updates a few other things to make it all work after the "Drop
CPU subtype IRQ headers" commit. It boots and runs fine on my titan
board.
- adds an ipr_idx to the ipr_data and uses a function in the subtype
code to calculate the address of the IPR registers
- adds a function to enable individual interrupt mode for externals
in the subtype code and calls that from the titan board code
instead of doing it directly.
- I changed the shift in the ipr_data to be the actual # of bits to
shift, instead of the numnber / 4 - made it easier to match with
the manual.
Signed-off-by: Jamie Lenehan <lenehan@twibble.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Previously this was using a static pgd shift in the reporting
code, simply flip this to PGDIR_SHIFT which does the right
thing depending on varying PTE magnitudes on the SH-X2 MMU.
While we're at it, and since it's been recently added, use
get_TTB() for fetching the TTB, rather than the open coded
instructions.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There were a number of places that made evil PAGE_SIZE == 4k
assumptions that ended up breaking when trying to play with
8k and 64k page sizes, this fixes those up.
The most significant change is the way we load THREAD_SIZE,
previously this was done via:
mov #(THREAD_SIZE >> 8), reg
shll8 reg
to avoid a memory access and allow the immediate load. With
a 64k PAGE_SIZE, we're out of range for the immediate load
size without resorting to special instructions available in
later ISAs (movi20s and so on). The "workaround" for this is
to bump up the shift to 10 and insert a shll2, which gives a
bit more flexibility while still being much cheaper than a
memory access.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Handle simple TLB miss faults which can be resolved completely
from the page table in assembler.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Remove extra bits from the pmd structure and store a kernel logical
address rather than a physical address. This allows it to be directly
dereferenced. Another piece of wierdness inherited from x86.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add TTB accessor functions and give it a sensible default
value. We will use this later for optimizing the fault
path.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Remove the previous saving of fault codes into the thread_struct
as they are never used, and appeared to be inherited from x86.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds some preliminary support for the SH-X2 MMU, used by
newer SH-4A parts (particularly SH7785).
This MMU implements a 'compat' mode with SH-X MMUs and an
'extended' mode for SH-X2 extended features. Extended features
include additional page sizes (8kB, 4MB, 64MB), as well as the
addition of page execute permissions.
The extended mode attributes are placed in a second data array,
which requires us to switch to 64-bit PTEs when in X2 mode.
With the addition of the exec perms, we also overhaul the mmap
prots somewhat, now that it's possible to handle them more
intelligently.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements initial support for the SH7206 (SH-2A) and SH7619
(SH-2) MMU-less CPUs.
Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This is an updated version of Eric Biederman's is_init() patch.
(http://lkml.org/lkml/2006/2/6/280). It applies cleanly to 2.6.18-rc3 and
replaces a few more instances of ->pid == 1 with is_init().
Further, is_init() checks pid and thus removes dependency on Eric's other
patches for now.
Eric's original description:
There are a lot of places in the kernel where we test for init
because we give it special properties. Most significantly init
must not die. This results in code all over the kernel test
->pid == 1.
Introduce is_init to capture this case.
With multiple pid spaces for all of the cases affected we are
looking for only the first process on the system, not some other
process that has pid == 1.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: <lxc-devel@lists.sourceforge.net>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make PROT_WRITE imply PROT_READ for a number of architectures which don't
support write only in hardware.
While looking at this, I noticed that some architectures which do not
support write only mappings already take the exact same approach. For
example, in arch/alpha/mm/fault.c:
"
if (cause < 0) {
if (!(vma->vm_flags & VM_EXEC))
goto bad_area;
} else if (!cause) {
/* Allow reads even for write-only mappings */
if (!(vma->vm_flags & (VM_READ | VM_WRITE)))
goto bad_area;
} else {
if (!(vma->vm_flags & VM_WRITE))
goto bad_area;
}
"
Thus, this patch brings other architectures which do not support write only
mappings in-line and consistent with the rest. I've verified the patch on
ia64, x86_64 and x86.
Additional discussion:
Several architectures, including x86, can not support write-only mappings.
The pte for x86 reserves a single bit for protection and its two states are
read only or read/write. Thus, write only is not supported in h/w.
Currently, if i 'mmap' a page write-only, the first read attempt on that page
creates a page fault and will SEGV. That check is enforced in
arch/blah/mm/fault.c. However, if i first write that page it will fault in
and the pte will be set to read/write. Thus, any subsequent reads to the page
will succeed. It is this inconsistency in behavior that this patch is
attempting to address. Furthermore, if the page is swapped out, and then
brought back the first read will also cause a SEGV. Thus, any arbitrary read
on a page can potentially result in a SEGV.
According to the SuSv3 spec, "if the application requests only PROT_WRITE, the
implementation may also allow read access." Also as mentioned, some
archtectures, such as alpha, shown above already take the approach that i am
suggesting.
The counter-argument to this raised by Arjan, is that the kernel is enforcing
the write only mapping the best it can given the h/w limitations. This is
true, however Alan Cox, and myself would argue that the inconsitency in
behavior, that is applications can sometimes work/sometimes fails is highly
undesireable. If you read through the thread, i think people, came to an
agreement on the last patch i posted, as nobody has objected to it...
Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Andi Kleen <ak@muc.de>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Ian Molton <spyro@f2s.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
IRQs disabling in flush_cache_4096 for cache purge. Under certain
workloads we would get an IRQ in the middle of a purge operation,
and the cachelines would remain in an inconsistent state, leading
to occasional stack corruption.
Signed-off-by: Takeo Takahashi <takahashi.takeo@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements initial support for the vsyscall page on SH.
At the moment we leave it configurable due to having nommu
to support from the same code base. We hook it up for the
signal trampoline return at present, with more to be added
later, once uClibc catches up.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
flush_cache_mm() wraps in to flush_cache_all(), which is rather
excessive given that the number of PTEs within the specified context
are generally quite low. Optimize for walking the mm's VMA list and
selectively flushing the VMA ranges from the dcache. Invalidate the
icache only if a VMA sets VM_EXEC.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds support for the aforementioned CPU subtypes, and cleans
up some build issues encountered as a result.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This fixes up some of the various outstanding nommu bugs on
SH.
Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
nommu needs to be able to shift PAGE_OFFSET, so we switch it to a
non-user-visible CONFIG_PAGE_OFFSET and use that in the few places
where it matters.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Inhibit mapping through page tables in __ioremap() for PCI memory
apertures on SH7751 and SH7780-style PCI controllers, translation is
not possible for these areas. For other users that map a small window
in P1/P2 space, ioremap() traps that already, and should never make
it to __ioremap().
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There was a bug that got introduced when the split ptlock changes
went in where mm could be unintialized for user mappings, this
fixes it up..
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
ioremap() overhaul. Add support for transparent PMB mapping, get rid of
p3_ioremap(), etc. Also drop ioremap() and iounmap() routines from the
machvec, as everyone can use the generic ioremap() API instead. For PCI
memory apertures and other special cases, use the pci_iomap() API, as
boards are already required to get the mapping right there.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cleanup of page table allocators, using generic folded PMD and PUD
helpers. TLB flushing operations are moved to a more sensible spot.
The page fault handler is also optimized slightly, we no longer waste
cycles on IRQ disabling for flushing of the page from the ITLB, since
we're already under CLI protection by the initial exception handler.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Currently when making changes to control registers, we
typically need some time for changes to take effect (8
nops, generally). However, for sh4a we simply need to
do an icbi..
This is a simple patch for implementing a general purpose
ctrl_barrier() which functions as a control register write
barrier. There's some additional documentation in the patch
itself, but it's pretty self explanatory.
There were also some places where we were not doing the
barrier, which didn't seem to have any adverse effects on
legacy parts, but certainly did on sh4a. It's safer to have
the barrier in place for legacy parts as well in these cases,
though this does make flush_tlb_all() more expensive (by an
order of 8 nops). We can ifdef around the flush_tlb_all()
case for now if it's clear that all legacy parts won't have
a problem with this.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
