Commit Graph

370 Commits

Author SHA1 Message Date
Luis Machado
d6a61bfc06 powerpc: BookE hardware watchpoint support
This patch implements support for HW based watchpoint via the
DBSR_DAC (Data Address Compare) facility of the BookE processors.

It does so by interfacing with the existing DABR breakpoint code
and adding the necessary bits and pieces for the new bits to
be properly set or cleared

Signed-off-by: Luis Machado <luisgpm@br.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-25 15:44:39 +10:00
Jon Tollefson
0d9ea75443 powerpc: support multiple hugepage sizes
Instead of using the variable mmu_huge_psize to keep track of the huge
page size we use an array of MMU_PAGE_* values.  For each supported huge
page size we need to know the hugepte_shift value and have a
pgtable_cache.  The hstate or an mmu_huge_psizes index is passed to
functions so that they know which huge page size they should use.

The hugepage sizes 16M and 64K are setup(if available on the hardware) so
that they don't have to be set on the boot cmd line in order to use them.
The number of 16G pages have to be specified at boot-time though (e.g.
hugepagesz=16G hugepages=5).

Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
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>
2008-07-24 10:47:19 -07:00
Jon Tollefson
91224346aa powerpc: define support for 16G hugepages
The huge page size is defined for 16G pages.  If a hugepagesz of 16G is
specified at boot-time then it becomes the huge page size instead of the
default 16M.

The change in pgtable-64K.h is to the macro pte_iterate_hashed_subpages to
make the increment to va (the 1 being shifted) be a long so that it is not
shifted to 0.  Otherwise it would create an infinite loop when the shift
value is for a 16G page (when base page size is 64K).

Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
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>
2008-07-24 10:47:19 -07:00
Jon Tollefson
658013e93e powerpc: scan device tree for gigantic pages
The 16G huge pages have to be reserved in the HMC prior to boot.  The
location of the pages are placed in the device tree.  This patch adds code
to scan the device tree during very early boot and save these page
locations until hugetlbfs is ready for them.

Acked-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
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>
2008-07-24 10:47:19 -07:00
Jon Tollefson
ec4b2c0c83 powerpc: function to allocate gigantic hugepages
The 16G page locations have been saved during early boot in an array.  The
alloc_bootmem_huge_page() function adds a page from here to the
huge_boot_pages list.

Acked-by: Adam Litke <agl@us.ibm.com>
Signed-off-by: Jon Tollefson <kniht@linux.vnet.ibm.com>
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>
2008-07-24 10:47:19 -07:00
Andi Kleen
ceb8687961 hugetlb: introduce pud_huge
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>
2008-07-24 10:47:18 -07:00
Andi Kleen
a551643895 hugetlb: modular state for hugetlb page size
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>
2008-07-24 10:47:17 -07:00
Jan Beulich
42b7772812 mm: remove double indirection on tlb parameter to free_pgd_range() & Co
The double indirection here is not needed anywhere and hence (at least)
confusing.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:15 -07:00
Benjamin Herrenschmidt
a1f242ff46 powerpc ioremap_prot
This adds ioremap_prot and pte_pgprot() so that one can extract protection
bits from a PTE and use them to ioremap_prot() (in order to support ptrace
of VM_IO | VM_PFNMAP as per Rik's patch).

This moves a couple of flag checks around in the ioremap implementations
of arch/powerpc.  There's a side effect of allowing non-cacheable and
non-guarded mappings on ppc32 which before would always have _PAGE_GUARDED
set whenever _PAGE_NO_CACHE is.

(standard ioremap will still set _PAGE_GUARDED, but ioremap_prot will be
capable of setting such a non guarded mapping).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-24 10:47:15 -07:00
Johannes Weiner
b61bfa3c46 mm: move bootmem descriptors definition to a single place
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>
2008-07-24 10:47:14 -07:00
Benjamin Herrenschmidt
84c3d4aaec Merge commit 'origin/master'
Manual merge of:

	arch/powerpc/Kconfig
	arch/powerpc/kernel/stacktrace.c
	arch/powerpc/mm/slice.c
	arch/ppc/kernel/smp.c
2008-07-16 11:07:59 +10:00
Stefan Roese
2bf3016f89 powerpc: Fix problems with 32bit PPC's running with >= 4GB of RAM
This patch enables 32bit PPC's (with 36bit physical address space, e.g.
IBM/AMCC PPC44x) to run with >= 4GB of RAM. Mostly its just replacing types
(unsigned long -> phys_addr_t).

Tested on an AMCC Katmai with 4GB of DDR2.

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-07-09 14:13:01 -04:00
Benjamin Herrenschmidt
1bc54c0311 powerpc: rework 4xx PTE access and TLB miss
This is some preliminary work to improve TLB management on SW loaded
TLB powerpc platforms. This introduce support for non-atomic PTE
operations in pgtable-ppc32.h and removes write back to the PTE from
the TLB miss handlers. In addition, the DSI interrupt code no longer
tries to fixup write permission, this is left to generic code, and
_PAGE_HWWRITE is gone.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-07-09 13:36:17 -04:00
Stephen Rothwell
392096e98f generic-ipi: fix linux-next tree build failure
Today's linux-next build (powerpc ppc64_defconfig) failed like this:

arch/powerpc/mm/tlb_64.c: In function 'pgtable_free_now':
arch/powerpc/mm/tlb_64.c:66: error: too many arguments to function 'smp_call_function'
arch/powerpc/kernel/machine_kexec_64.c: In function 'kexec_prepare_cpus':
arch/powerpc/kernel/machine_kexec_64.c:175: error: too many arguments to function 'smp_call_function'

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: <linuxppc-dev@ozlabs.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-03 09:25:42 +02:00
Nathan Fontenot
0db9360aaa powerpc/pseries: Update numa association of hotplug memory add for drconf memory
Update the association of a memory section with a numa node that
occurs during hotplug add of a memory section.  This adds a check in
the hot_add_scn_to_nid() routine for the
ibm,dynamic-reconfiguration-memory node in the device tree.  If
present the new hot_add_drconf_scn_to_nid() routine is invoked, which
can properly parse the ibm,dynamic-reconfiguration-memory node of the
device tree and make the proper numa node associations.

This also introduces the valid_hot_add_scn() routine as a helper
function for code that is common to the hot_add_scn_to_nid() and
hot_add_drconf_scn_to_nid() routines.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:18 +10:00
Nathan Fontenot
8342681d3e powerpc/pseries: Split code into helper routines for drconf memory
This splits off several pieces of code that parse the
ibm,dynamic-reconfiguration-memory node of the device tree into separate
helper routines.  This is in preparation for the next commit that will
use these helper routines.  There are no functional changes in this patch.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:17 +10:00
Tony Breeds
db7f37de2c powerpc: Fix building of arch/powerpc/mm/mem.o when MEMORY_HOTPLUG=y and SPARSEMEM=n
Currently the kernel fails to build with the above config options with:
  CC      arch/powerpc/mm/mem.o
arch/powerpc/mm/mem.c: In function 'arch_add_memory':
arch/powerpc/mm/mem.c:130: error: implicit declaration of function 'create_section_mapping'

This explicitly includes asm/sparsemem.h in arch/powerpc/mm/mem.c and
moves the guards in include/asm-powerpc/sparsemem.h to protect the
SPARSEMEM specific portions only.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:07 +10:00
Dave Kleikamp
87e9ab13c3 powerpc: hash_huge_page() should get the WIMG bits from the lpte
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Jon Tollefson <kniht@linux.vnet.ibm.com>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:02 +10:00
Paul Mackerras
3a8247cc2c powerpc: Only demote individual slices rather than whole process
At present, if we have a kernel with a 64kB page size, and some
process maps something that has to be mapped with 4kB pages (such as a
cache-inhibited mapping on POWER5+, or the eHCA infiniband queue-pair
pages), we change the process to use 4kB pages everywhere.  This hurts
the performance of HPC programs that access eHCA from userspace.

With this patch, the kernel will only demote the slice(s) containing
the eHCA or cache-inhibited mappings, leaving the remaining slices
able to use 64kB hardware pages.

This also changes the slice_get_unmapped_area code so that it is
willing to place a 64k-page mapping into (or across) a 4k-page slice
if there is no better alternative, i.e. if the program specified
MAP_FIXED or if there is not sufficient space available in slices that
are either empty or already have 64k-page mappings in them.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-01 11:27:57 +10:00
Becky Bruce
316a405841 powerpc: Get rid of bitfields in ppc_bat struct
While working on the 36-bit physical support, I noticed that there
was exactly one line of code that actually referenced the bitfields.
So I got rid of them and redefined ppc_bat as a struct of 2 u32's:
batu and batl.  I also got rid of the previous union that held the
bitfield structs and a word representation of the batu/l values.

This seems like a nicer solution than adding in a bunch of
new bitfields to support extended bat addressing that would never
get used, and just leaving the struct as-is would have been
incomplete in the face of large physical addressing.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-30 22:31:05 +10:00
Becky Bruce
7c5c4325d2 powerpc: Change BAT code to use phys_addr_t
Currently, the physical address is an unsigned long, but it should
be phys_addr_t in set_bat, [v/p]_mapped_by_bat.  Also, create a
macro that can convert a large physical address into the correct
format for programming the BAT registers.

Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-30 22:31:03 +10:00
Benjamin Herrenschmidt
41743a4e34 powerpc: Free a PTE bit on ppc64 with 64K pages
This frees a PTE bit when using 64K pages on ppc64.  This is done
by getting rid of the separate _PAGE_HASHPTE bit.  Instead, we just test
if any of the 16 sub-page bits is set.  For non-combo pages (ie. real
64K pages), we set SUB0 and the location encoding in that field.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-30 22:30:53 +10:00
Paul Mackerras
e9a4b6a3f6 Merge branch 'linux-2.6' 2008-06-30 10:16:50 +10:00
Jens Axboe
15c8b6c1aa on_each_cpu(): kill unused 'retry' parameter
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.

Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:24:38 +02:00
Paul Mackerras
65ba6cdc83 [POWERPC] Clear sub-page HPTE present bits when demoting page size
When we demote a slice from 64k to 4k, and we are about to insert an
HPTE for a 4k subpage and we notice that there is an existing 64k
HPTE, we first invalidate that HPTE before inserting the new 4k
subpage HPTE.  Since the bits that encode which hash bucket the old
HPTE was in overlap with the bits that encode which of the 16 subpages
have HPTEs, we need to clear out the subpage HPTE-present bits before
starting to insert HPTEs for the 4k subpages.  If we don't do that, we
can erroneously think that a subpage already has an HPTE when it
doesn't.

That in itself wouldn't be such a problem except that when we go to
update the HPTE that we think is present on machines with a
hypervisor, the hypervisor can tell us that the HPTE we think is there
is actually there even though it isn't, which can lead to a process
getting stuck in a loop, continually faulting.  The reason for the
confusion is that the AVPN (abbreviated virtual page number) we are
looking for in the HPTE for a 4k subpage can actually match the AVPN
in a stale HPTE for another 64k page.  For example, the HPTE for
the 4k subpage at 0x84000f000 will be in the same hash bucket and have
the same AVPN as the HPTE for the 64k page at 0x8400f0000.

This fixes the code to clear out the subpage HPTE-present bits.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-18 21:40:43 +10:00
Paul Mackerras
8a3e1c670e Merge branch 'merge'
Conflicts:

	arch/powerpc/sysdev/fsl_soc.c
2008-06-09 12:19:41 +10:00
Nathan Lynch
0d5799449f [POWERPC] Make walk_memory_resource available with MEMORY_HOTPLUG=n
The ehea driver was recently changed[1] to use walk_memory_resource() to
detect the system's memory layout.  However, walk_memory_resource() is
available only when memory hotplug is enabled.  So CONFIG_EHEA was
made to depend on MEMORY_HOTPLUG [2], but it is inappropriate for a
network driver to have such a dependency.

Make the declaration of walk_memory_resource() and its powerpc
implementation (ehea is powerpc-specific) unconditionally available.

[1] 48cfb14f8b
    "ehea: Add DLPAR memory remove support"

[2] fb7b6ca2b6
    "ehea: Add dependency to Kconfig"

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Acked-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-09 11:32:41 +10:00
Paul Mackerras
acf464817d Merge branch 'merge' into powerpc-next 2008-05-23 16:53:23 +10:00
David Gibson
46a7417963 [POWERPC] Fix __set_fixmap() for STRICT_MM_TYPECHECKS
__set_fixmap() in pgtable_32.c currently fails to compile if
STRICT_MM_TYPECHECKS is defined.  This fixes it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-23 16:15:32 +10:00
Adrian Bunk
d3d3d3cdb1 [POWERPC] powerpc/mm/hash_low_32.S: Remove CVS keyword
This removes a CVS keyword that wasn't updated for a long time from a
comment.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-20 09:34:18 +10:00
Paul Mackerras
fcff474ea5 Merge branch 'linux-2.6' into powerpc-next 2008-05-16 23:13:42 +10:00
Benjamin Herrenschmidt
cec08e7a94 [POWERPC] vmemmap fixes to use smaller pages
This changes vmemmap to use a different region (region 0xf) of the
address space, and to configure the page size of that region
dynamically at boot.

The problem with the current approach of always using 16M pages is that
it's not well suited to machines that have small amounts of memory such
as small partitions on pseries, or PS3's.

In fact, on the PS3, failure to allocate the 16M page backing vmmemmap
tends to prevent hotplugging the HV's "additional" memory, thus limiting
the available memory even more, from my experience down to something
like 80M total, which makes it really not very useable.

The logic used by my match to choose the vmemmap page size is:

 - If 16M pages are available and there's 1G or more RAM at boot,
   use that size.
 - Else if 64K pages are available, use that
 - Else use 4K pages

I've tested on a POWER6 (16M pages) and on an iSeries POWER3 (4K pages)
and it seems to work fine.

Note that I intend to change the way we organize the kernel regions &
SLBs so the actual region will change from 0xf back to something else at
one point, as I simplify the SLB miss handler, but that will be for a
later patch.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-15 20:49:25 +10:00
Michael Ellerman
c884116ac3 [POWERPC] Remove duplicate variable definitions in mm/tlb_64.c
Somewhere along the way (e28f7faf05,
"Four level pagetables for ppc64") we ended up with duplicate
definitions for pte_freelist_cur and pte_freelist_force_free.
Somehow this compiles, but it would be better to just have one
definition for each.

The two definitions we end up with can be static too!

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-14 22:31:49 +10:00
Michael Ellerman
572fb578de [POWERPC] Move declaration of tce variables into mmu-hash64.h
... instead of having extern declarations in a .c file.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-14 22:31:47 +10:00
Michael Ellerman
09de9ff872 [POWERPC] Fix sparse warnings in arch/powerpc/mm
Make two vmemmap helpers static in init_64.c
Make stab variables static in stab.c
Make psize defs static in hash_utils_64.c

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-14 22:31:46 +10:00
Michael Ellerman
5f25f06529 [POWERPC] Move declaration of init_bootmem_done into system.h
... instead of having an extern declaration in a .c file.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-14 22:31:44 +10:00
Paul Mackerras
3b5750644b [POWERPC] Bolt in SLB entry for kernel stack on secondary cpus
This fixes a regression reported by Kamalesh Bulabel where a POWER4
machine would crash because of an SLB miss at a point where the SLB
miss exception was unrecoverable.  This regression is tracked at:

http://bugzilla.kernel.org/show_bug.cgi?id=10082

SLB misses at such points shouldn't happen because the kernel stack is
the only memory accessed other than things in the first segment of the
linear mapping (which is mapped at all times by entry 0 of the SLB).
The context switch code ensures that SLB entry 2 covers the kernel
stack, if it is not already covered by entry 0.  None of entries 0
to 2 are ever replaced by the SLB miss handler.

Where this went wrong is that the context switch code assumes it
doesn't have to write to SLB entry 2 if the new kernel stack is in the
same segment as the old kernel stack, since entry 2 should already be
correct.  However, when we start up a secondary cpu, it calls
slb_initialize, which doesn't set up entry 2.  This is correct for
the boot cpu, where we will be using a stack in the kernel BSS at this
point (i.e. init_thread_union), but not necessarily for secondary
cpus, whose initial stack can be allocated anywhere.  This doesn't
cause any immediate problem since the SLB miss handler will just
create an SLB entry somewhere else to cover the initial stack.

In fact it's possible for the cpu to go quite a long time without SLB
entry 2 being valid.  Eventually, though, the entry created by the SLB
miss handler will get overwritten by some other entry, and if the next
access to the stack is at an unrecoverable point, we get the crash.

This fixes the problem by making slb_initialize create a suitable
entry for the kernel stack, if we are on a secondary cpu and the stack
isn't covered by SLB entry 0.  This requires initializing the
get_paca()->kstack field earlier, so I do that in smp_create_idle
where the current field is initialized.  This also abstracts a bit of
the computation that mk_esid_data in slb.c does so that it can be used
in slb_initialize.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-02 15:00:45 +10:00
Geoff Levand
bbea346062 [POWERPC] Fix slb.c compile warnings
Arrange for a syntax check to always be done on the powerpc/mm/slb.c
DBG() macro by defining it to pr_debug() for non-debug builds.

Also, fix these related compile warnings:

  slb.c:273: warning: format '%04x' expects type 'unsigned int', but argument 2 has type 'long unsigned int
  slb.c:274: warning: format '%04x' expects type 'unsigned int', but argument 2 has type 'long unsigned int'

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-05-02 15:00:44 +10:00
Badari Pulavarty
9d88a2eb6e [POWERPC] Provide walk_memory_resource() for powerpc
Provide walk_memory_resource() for 64-bit powerpc.  PowerPC maintains
logical memory region mapping in the lmb.memory structure.  Walk
through these structures and do the callbacks for the contiguous
chunks.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-29 15:57:53 +10:00
Jeremy Fitzhardinge
180c06efce hotplug-memory: make online_page() common
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>
2008-04-28 08:58:17 -07:00
Kumar Gala
f608600e74 [POWERPC] Clean up access to thread_info in assembly
Use (31-THREAD_SHIFT) to get to thread_info from stack pointer.  This makes
the code a bit easier to read and more robust if we ever change THREAD_SHIFT.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 20:58:02 +10:00
Kumar Gala
2c419bdeca [POWERPC] Port fixmap from x86 and use for kmap_atomic
The fixmap code from x86 allows us to have compile time virtual addresses
that we change the physical addresses of at run time.

This is useful for applications like kmap_atomic, PCI config that is done
via direct memory map, kexec/kdump.

We got ride of CONFIG_HIGHMEM_START as we can now determine a more optimal
location for PKMAP_BASE based on where the fixmap addresses start and
working back from there.

Additionally, the kmap code in asm-powerpc/highmem.h always had debug
enabled.  Moved to using CONFIG_DEBUG_HIGHMEM to determine if we should
have the extra debug checking.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 20:58:02 +10:00
Kumar Gala
37dd2badcf [POWERPC] 85xx: Add support for relocatable kernel (and booting at non-zero)
Added support to allow an 85xx kernel to be run from a non-zero physical
address (useful for cooperative asymmetric multiprocessing situations and
kdump).  The support can be configured at compile time by setting
CONFIG_PAGE_OFFSET, CONFIG_KERNEL_START, and CONFIG_PHYSICAL_START as
desired.

Alternatively, the kernel build can set CONFIG_RELOCATABLE.  Setting this
config option causes the kernel to determine at runtime the physical
addresses of CONFIG_PAGE_OFFSET and CONFIG_KERNEL_START.  If
CONFIG_RELOCATABLE is set, then CONFIG_PHYSICAL_START has no meaning.
However, CONFIG_PHYSICAL_START will always be used to set the LOAD program
header physical address field in the resulting ELF image.

Currently we are limited to running at a physical address that is a
multiple of 256M.  This is due to how we map TLBs to cover
lowmem.  This should be fixed to allow 64M or maybe even 16M alignment
in the future.  It is considered an error to try and run a kernel at a
non-aligned physical address.

All the magic for this support is accomplished by proper initialization
of the kernel memory subsystem and use of ARCH_PFN_OFFSET.

The use of ARCH_PFN_OFFSET only affects normal memory and not IO mappings.
ioremap uses map_page and isn't affected by ARCH_PFN_OFFSET.

/dev/mem continues to allow access to any physical address in the system
regardless of how CONFIG_PHYSICAL_START is set.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 20:58:01 +10:00
Michael Ellerman
6df1646e31 [POWERPC] Add include of linux/of.h to numa.c
numa.c requires routines declared in linux/of.h, so should include it.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 20:57:32 +10:00
Olof Johansson
49a9997884 [POWERPC] Remove unused __max_memory variable
Remove the __max_memory variable, as it is not referenced anywhere
in the tree besides some code in arch/ppc.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-18 15:37:11 +10:00
Kumar Gala
7711684947 [POWERPC] Remove unused machine call outs
When we moved to arch/powerpc we actively tried to avoid using the
ppc_md.setup_io_mappings().  Currently no board ports use it so let's
remove it to avoid any new boards using it.

Also, remove early_serial_map() since we don't even have a call out for
it in arch/powerpc.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 10:01:00 +10:00
Kumar Gala
09b5e63f82 [POWERPC] Rename __initial_memory_limit to __initial_memory_limit_addr
We always use __initial_memory_limit as an address so rename it
to be clear.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 07:46:13 +10:00
Kumar Gala
0aef996b37 [POWERPC] 85xx: Cleanup TLB initialization
* Determine the RPN we are running the kernel at runtime rather
  than using compile time constant for initial TLB

* Cleanup adjust_total_lowmem() to respect memstart_addr and
  be a bit more clear on variables that are sizes vs addresses.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 07:46:13 +10:00
Kumar Gala
d7917ba705 [POWERPC] Introduce lowmem_end_addr to distinguish from total_lowmem
total_lowmem represents the amount of low memory, not the physical
address that low memory ends at.  If the start of memory is at 0 it
happens that total_lowmem can be used as both the size and the address
that lowmem ends at (or more specifically one byte beyond the end).

To make the code a bit more clear and deal with the case when the start of
memory isn't at physical 0, we introduce lowmem_end_addr that represents
one byte beyond the last physical address in the lowmem region.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 07:46:13 +10:00
Kumar Gala
99c62dd773 [POWERPC] Remove and replace uses of PPC_MEMSTART with memstart_addr
A number of users of PPC_MEMSTART (40x, ppc_mmu_32) can just always
use 0 as we don't support booting these kernels at non-zero physical
addresses since their exception vectors must be at 0 (or 0xfffx_xxxx).

For the sub-arches that support relocatable interrupt vectors
(book-e), it's reasonable to have memory start at a non-zero physical
address.  For those cases use the variable memstart_addr instead of
the #define PPC_MEMSTART since the only uses of PPC_MEMSTART are for
initialization and in the future we can set memstart_addr at runtime
to have a relocatable kernel.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 07:46:12 +10:00