Commit graph

153 commits

Author SHA1 Message Date
Scott Wood
6dd2270029 powerpc: Fix memory limits when starting at a non-zero address
memblock_enforce_memory_limit() takes the desired maximum quantity of memory
to end up with, not an address above which memory will not be used.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-03-02 16:56:15 +11:00
Grant Likely
672c54466d dt/flattree: Return virtual address from early_init_dt_alloc_memory_arch()
The physical address is never used by the device tree code when
allocating memory for unflattening.  Change the architecture's alloc
hook to return the virutal address instead.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-01-15 22:01:58 -07:00
Linus Torvalds
51f00a471c Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6
* 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6:
  mtd/m25p80: add support to parse the partitions by OF node
  of/irq: of_irq.c needs to include linux/irq.h
  of/mips: Cleanup some include directives/files.
  of/mips: Add device tree support to MIPS
  of/flattree: Eliminate need to provide early_init_dt_scan_chosen_arch
  of/device: Rework to use common platform_device_alloc() for allocating devices
  of/xsysace: Fix OF probing on little-endian systems
  of: use __be32 types for big-endian device tree data
  of/irq: remove references to NO_IRQ in drivers/of/platform.c
  of/promtree: add package-to-path support to pdt
  of/promtree: add of_pdt namespace to pdt code
  of/promtree: no longer call prom_ functions directly; use an ops structure
  of/promtree: make drivers/of/pdt.c no longer sparc-only
  sparc: break out some PROM device-tree building code out into drivers/of
  of/sparc: convert various prom_* functions to use phandle
  sparc: stop exporting openprom.h header
  powerpc, of_serial: Endianness issues setting up the serial ports
  of: MTD: Fix OF probing on little-endian systems
  of: GPIO: Fix OF probing on little-endian systems
2010-10-25 08:19:14 -07:00
Grant Likely
32c97689c4 of/flattree: Eliminate need to provide early_init_dt_scan_chosen_arch
This patch refactors the early init parsing of the chosen node so that
architectures aren't forced to provide an empty implementation of
early_init_dt_scan_chosen_arch.  Instead, if an architecture wants to
do something different, it can either use a wrapper function around
early_init_dt_scan_chosen(), or it can replace it altogether.

This patch was written in preparation to adding device tree support to
both x86 ad MIPS.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: David Daney <ddaney@caviumnetworks.com>
2010-10-21 11:10:10 -06:00
Benjamin Herrenschmidt
cd3db0c4ca memblock: Remove rmo_size, burry it in arch/powerpc where it belongs
The RMA (RMO is a misnomer) is a concept specific to ppc64 (in fact
server ppc64 though I hijack it on embedded ppc64 for similar purposes)
and represents the area of memory that can be accessed in real mode
(aka with MMU off), or on embedded, from the exception vectors (which
is bolted in the TLB) which pretty much boils down to the same thing.

We take that out of the generic MEMBLOCK data structure and move it into
arch/powerpc where it belongs, renaming it to "RMA" while at it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:08 +10:00
Benjamin Herrenschmidt
e63075a3c9 memblock: Introduce default allocation limit and use it to replace explicit ones
This introduce memblock.current_limit which is used to limit allocations
from memblock_alloc() or memblock_alloc_base(..., MEMBLOCK_ALLOC_ACCESSIBLE).

The old MEMBLOCK_ALLOC_ANYWHERE changes value from 0 to ~(u64)0 and can still
be used with memblock_alloc_base() to allocate really anywhere.

It is -no-longer- cropped to MEMBLOCK_REAL_LIMIT which disappears.

Note to archs: I'm leaving the default limit to MEMBLOCK_ALLOC_ANYWHERE. I
strongly recommend that you ensure that you set an appropriate limit
during boot in order to guarantee that an memblock_alloc() at any time
results in something that is accessible with a simple __va().

The reason is that a subsequent patch will introduce the ability for
the array to resize itself by reallocating itself. The MEMBLOCK core will
honor the current limit when performing those allocations.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:07 +10:00
Benjamin Herrenschmidt
3fdfd99051 powerpc: Fix erroneous lmb->memblock conversions
Oooops... we missed these. We incorrectly converted strings
used when parsing the device-tree on pseries, thus breaking
access to drconf memory and hotplug memory.

While at it, also revert some variable names that represent
something the FW calls "lmb" and thus don't need to be converted
to "memblock".

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
2010-07-23 12:56:57 +10:00
Yinghai Lu
95f72d1ed4 lmb: rename to memblock
via following scripts

      FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')

      sed -i \
        -e 's/lmb/memblock/g' \
        -e 's/LMB/MEMBLOCK/g' \
        $FILES

      for N in $(find . -name lmb.[ch]); do
        M=$(echo $N | sed 's/lmb/memblock/g')
        mv $N $M
      done

and remove some wrong change like lmbench and dlmb etc.

also move memblock.c from lib/ to mm/

Suggested-by: Ingo Molnar <mingo@elte.hu>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-14 17:14:00 +10:00
Michael Ellerman
1426d5a3bd powerpc: Dynamically allocate pacas
On 64-bit kernels we currently have a 512 byte struct paca_struct for
each cpu (usually just called "the paca"). Currently they are statically
allocated, which means a kernel built for a large number of cpus will
waste a lot of space if it's booted on a machine with few cpus.

We can avoid that by only allocating the number of pacas we need at
boot. However this is complicated by the fact that we need to access
the paca before we know how many cpus there are in the system.

The solution is to dynamically allocate enough space for NR_CPUS pacas,
but then later in boot when we know how many cpus we have, we free any
unused pacas.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-03-09 11:52:52 +11:00
Grant Likely
fc0bdae49d of: move definition of of_chosen into common code.
Rather than defining of_chosen in each arch, it can be defined for all
in driver/of/base.c

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Michal Simek <monstr@monstr.eu>
2010-02-14 07:13:55 -07:00
Grant Likely
22d5579e66 of: remove unused extern reference to devtree_lock
Neither the powerpc nor the microblaze code use devtree_lock anymore.
Remove the extern reference.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Michal Simek <monstr@monstr.eu>
2010-02-14 07:13:52 -07:00
Jeremy Kerr
4ef7b373df of/flattree: Don't assume HAVE_LMB
We don't always have lmb available, so make arches provide an
early_init_dt_alloc_memory_arch() to handle the allocation of
memory in the fdt code.

When we don't have lmb.h included, we need asm/page.h for __va.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Michal Simek <monstr@monstr.eu>
2010-02-14 07:13:47 -07:00
Jeremy Kerr
087f79c48c of/flattree: endian-convert members of boot_param_header
The boot_param_header has big-endian fields, so change the types to
__be32, and perform endian conversion when we access them.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-02-09 08:34:10 -07:00
Jeremy Kerr
1406bc2f57 of/flattree: use callback to setup initrd from /chosen
At present, the fdt code sets the kernel-wide initrd_start and
initrd_end variables when parsing /chosen. On ARM, we only set these
once the bootmem has been reserved.

This change adds an arch hook to setup the initrd from the device
tree:

 void early_init_dt_setup_initrd_arch(unsigned long start,
				      unsigned long end);

The arch-specific code can then setup the initrd however it likes.

Compiled on powerpc, with CONFIG_BLK_DEV_INITRD=y and =n.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-02-09 08:34:10 -07:00
Grant Likely
51975db0b7 of/flattree: merge early_init_dt_scan_memory() common code
Merge common code between PowerPC and Microblaze architectures.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Michal Simek <monstr@monstr.eu>
2010-02-09 08:33:10 -07:00
Jeremy Kerr
89751a7cb7 of: merge of_find_node_by_phandle
Merge common function between powerpc, sparc and microblaze. Code is
identical for powerpc and microblaze, but adds a lock (and release) of
the devtree_lock on sparc.

Signed-off-by: Jeremy Kerr <jeremy.kerr@canonical.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-02-09 08:32:48 -07:00
Grant Likely
fcdeb7fedf of: merge of_attach_node() & of_detach_node()
Merge common code between PowerPC and Microblaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-02-09 08:32:42 -07:00
Grant Likely
6016a363f6 of: unify phandle name in struct device_node
In struct device_node, the phandle is named 'linux_phandle' for PowerPC
and MicroBlaze, and 'node' for SPARC.  There is no good reason for the
difference, it is just an artifact of the code diverging over a couple
of years.  This patch renames both to simply .phandle.

Note: the .node also existed in PowerPC/MicroBlaze, but the only user
seems to be arch/powerpc/platforms/powermac/pfunc_core.c.  It doesn't
look like the assignment between .linux_phandle and .node is
significantly different enough to warrant the separate code paths
unless ibm,phandle properties actually appear in Apple device trees.

I think it is safe to eliminate the old .node property and use
phandle everywhere.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-01-28 14:06:53 -07:00
Grant Likely
923f7e30b4 of: Merge of_node_get() and of_node_put()
Merge common code between PowerPC and MicroBlaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-01-28 13:52:53 -07:00
Grant Likely
1f43cfb947 of: merge machine_is_compatible()
Merge common code between PowerPC and Microblaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-01-28 13:47:25 -07:00
Grant Likely
86e0322134 of/flattree: merge early_init_dt_scan_chosen()
Merge common code between PowerPC and Microblaze.  This patch
splits the arch-specific stuff out into a new function,
early_init_dt_scan_chosen_arch().

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-10 23:42:21 -07:00
Grant Likely
0f0b56c3f2 of/flattree: eliminate cell_t typedef
A cell is firmly established as a u32.  No need to do an ugly typedef
to redefine it to cell_t.  Eliminate the unnecessary typedef so that
it doesn't have to be added to the of_fdt header file

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-10 23:42:17 -07:00
Grant Likely
83f7a06eb4 of/flattree: merge dt_mem_next_cell
Merge common code between PowerPC and Microblaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
2009-12-10 15:23:15 -07:00
Grant Likely
f00abd9491 of/flattree: Merge earlyinit_dt_scan_root()
Merge common code between PowerPC and Microblaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
2009-12-10 15:23:15 -07:00
Grant Likely
f7b3a8355b of/flattree: Merge early_init_dt_check_for_initrd()
Merge common code between PowerPC and Microblaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-10 15:18:03 -07:00
Grant Likely
02af11b03f of: merge prom_{add,remove,modify}_property
Merge common code between PowerPC and MicroBlaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>
2009-11-23 20:16:45 -07:00
Grant Likely
41f880091c of/flattree: Merge unflatten_device_tree
Merge common code between PowerPC and MicroBlaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>
2009-11-23 20:07:01 -07:00
Grant Likely
bbd33931a0 of/flattree: Merge unflatten_dt_node
Merge common code between PowerPC and MicroBlaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>
2009-11-23 20:07:00 -07:00
Grant Likely
00e38efd90 of/flattree: Merge of_flat_dt_is_compatible
Merge common code between PowerPC and Microblaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>
2009-11-23 20:07:00 -07:00
Grant Likely
ca900cfa29 of/flattree: merge of_get_flat_dt_prop
Merge common code between PowerPC and Microblaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>
2009-11-23 20:06:59 -07:00
Grant Likely
819d281930 of/flattree: merge of_get_flat_dt_root
Merge common code between PowerPC and MicroBlaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>
2009-11-23 19:44:23 -07:00
Grant Likely
c8cb7a5984 of/flattree: merge of_scan_flat_dt
Merge common code between PowerPC and Microblaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>
2009-11-23 18:54:23 -07:00
Grant Likely
e169cfbef4 of/flattree: merge find_flat_dt_string and initial_boot_params
Merge common code between Microblaze and PowerPC.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Michal Simek <monstr@monstr.eu>
2009-11-23 14:53:09 -07:00
Grant Likely
e91edcf5a2 of: merge of_find_all_nodes() implementations
Merge common code between Microblaze and PowerPC, and make it available
to Sparc

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Michal Simek <monstr@monstr.eu>
Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
2009-10-15 10:58:09 -06:00
Benjamin Herrenschmidt
944916858a powerpc: Shield code specific to 64-bit server processors
This is a random collection of added ifdef's around portions of
code that only mak sense on server processors. Using either
CONFIG_PPC_STD_MMU_64 or CONFIG_PPC_BOOK3S as seems appropriate.

This is meant to make the future merging of Book3E 64-bit support
easier.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-06-09 16:47:38 +10:00
Becky Bruce
49a8496525 powerpc: Allow mem=x cmdline to work with 4G+
We're currently choking on mem=4g (and above) due to memory_limit
being specified as an unsigned long. Make memory_limit
phys_addr_t to fix this.

Signed-off-by: Becky Bruce <beckyb@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-05-15 16:43:41 +10:00
Michael Ellerman
059f134f84 powerpc: Allow debugging of LMBs with lmb=debug
The lmb debugging can be turned on at boottime with lmb=debug on the
command line. However on powerpc that doesn't work, because we don't
necessarily call lmb_dump_all().

So always call lmb_dump_all() after lmb_analyze(), no output is
generated unless lmb=debug is found on the command line.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-11 13:38:00 +11:00
Michael Neuling
b60c31d85a powerpc: Get the number of SLBs from "slb-size" property
The PAPR says that the property for specifying the number of SLBs should
be called "slb-size".  We currently only look for "ibm,slb-size" because
this is what firmware actually presents.

This patch makes us look for the "slb-size" property as well and in
preference to the "ibm,slb-size".  This should future proof us if
firmware changes to match PAPR.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-01-16 16:15:16 +11:00
Stephen Rothwell
6327716131 powerpc: Remove unnecessary casts
of_get_flat_dt_prop() returns a "void *", so we don't need to cast when
assigning its result to a pointer variable.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-01-08 16:25:16 +11:00
Hollis Blanchard
6ca4f7494b powerpc: Force memory size to be a multiple of PAGE_SIZE
Ensure that total memory size is page-aligned, because otherwise
mark_bootmem() gets upset.

This error case was triggered by using 64 KiB pages in the kernel
while arch/powerpc/boot/4xx.c arbitrarily reduced the amount of memory
by 4096 (to work around a chip bug that affects the last 256 bytes of
physical memory).

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-12-29 09:53:14 +11:00
Nathan Lynch
e523f723d6 powerpc: Add of_find_next_cache_node()
We have more than one piece of code that looks up cache nodes manually
using the "l2-cache" property.  Add a common helper routine which does
this and handles ePAPR's "next-level-cache" property as well as
powermac.

Signed-off-by: Nathan Lynch <ntl@pobox.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-12-21 14:21:14 +11:00
Paul Mackerras
549e8152de powerpc: Make the 64-bit kernel as a position-independent executable
This implements CONFIG_RELOCATABLE for 64-bit by making the kernel as
a position-independent executable (PIE) when it is set.  This involves
processing the dynamic relocations in the image in the early stages of
booting, even if the kernel is being run at the address it is linked at,
since the linker does not necessarily fill in words in the image for
which there are dynamic relocations.  (In fact the linker does fill in
such words for 64-bit executables, though not for 32-bit executables,
so in principle we could avoid calling relocate() entirely when we're
running a 64-bit kernel at the linked address.)

The dynamic relocations are processed by a new function relocate(addr),
where the addr parameter is the virtual address where the image will be
run.  In fact we call it twice; once before calling prom_init, and again
when starting the main kernel.  This means that reloc_offset() returns
0 in prom_init (since it has been relocated to the address it is running
at), which necessitated a few adjustments.

This also changes __va and __pa to use an equivalent definition that is
simpler.  With the relocatable kernel, PAGE_OFFSET and MEMORY_START are
constants (for 64-bit) whereas PHYSICAL_START is a variable (and
KERNELBASE ideally should be too, but isn't yet).

With this, relocatable kernels still copy themselves down to physical
address 0 and run there.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-15 11:08:38 -07:00
Chandru
cf00085d80 powerpc: Add support for dynamic reconfiguration memory in kexec/kdump kernels
Kdump kernel needs to use only those memory regions that it is allowed
to use (crashkernel, rtas, tce, etc.).  Each of these regions have
their own sizes and are currently added under 'linux,usable-memory'
property under each memory@xxx node of the device tree.

The ibm,dynamic-memory property of ibm,dynamic-reconfiguration-memory
node (on POWER6) now stores in it the representation for most of the
logical memory blocks with the size of each memory block being a
constant (lmb_size).  If one or more or part of the above mentioned
regions lie under one of the lmb from ibm,dynamic-memory property,
there is a need to identify those regions within the given lmb.

This makes the kernel recognize a new 'linux,drconf-usable-memory'
property added by kexec-tools.  Each entry in this property is of the
form of a count followed by that many (base, size) pairs for the above
mentioned regions.  The number of cells in the count value is given by
the #size-cells property of the root node.

Signed-off-by: Chandru Siddalingappa <chandru@in.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-15 11:07:58 -07:00
Michael Neuling
b962ce9d26 powerpc: Add VSX CPU feature
Add a VSX CPU feature.  Also add code to detect if VSX is available
from the device tree.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Joel Schopp <jschopp@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:47 +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
Benjamin Herrenschmidt
f4ac7b5eb7 [POWERPC] Fix device-tree locking vs. interrupts
Lockdep found out that we can occasionally take the device-tree
lock for reading from softirq time (from rtas_token called
by the rtas real time clock code called by the NTP code),
while we take it occasionally for writing without masking
interrupts. The combination of those two can thus deadlock.

While some of those cases of interrupt read lock could be fixed
(such as caching the RTAS tokens) I figured that taking the
lock for writing is so rare (device-tree modification) that we
may as well penalize that case and allow reading from interrupts.

Thus, this turns all the writers to take the lock with irqs
masked to avoid the situation.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-18 15:37:16 +10:00
Manish Ahuja
37ddd5d053 [POWERPC] pseries/phyp dump: Reserve a variable amount of space at boot
This changes the way we calculate how much space to reserve for the
pHyp dump.  Currently we reserve 256MB only.  With this change, the
code first checks to see if an amount has been specified on the boot
command line with the "phyp_dump_reserve_size" option, and if so, uses
that much.

Otherwise it computes 5% of total ram and rounds it down to a multiple
of 256MB, and uses the larger of that or 256MB.

This is for large systems with a lot of memory (10GB or more).  The
aim is to have more space available for the kernel on reboot on
machines with more resources.  Although the dump will be collected
pretty fast and the memory released really early on allowing the
machine to have the full memory available, this alleviates any issues
that can be caused by having way too little memory on very very large
systems during those few minutes.

Signed-off-by: Manish Ahuja <mahuja@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-17 07:46:14 +10:00
Geert Uytterhoeven
18f032cb51 [POWERPC] move_device_tree() should be __init
WARNING: vmlinux.o(.text+0x1e4c0): Section mismatch in reference from the
function .move_device_tree() to the function .init.text:.lmb_alloc_base()
The function .move_device_tree() references
the function __init .lmb_alloc_base().
This is often because .move_device_tree lacks a __init
annotation or the annotation of .lmb_alloc_base is wrong.

move_device_tree() is called from early_init_devtree() only, which is __init

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-01 20:43:08 +11:00
Manish Ahuja
654f596da4 [POWERPC] pseries: phyp dump: Disable phyp-dump through boot-var
This adds a kernel command line option "phyp_dump", which takes a 0/1
value for disabling/ enabling phyp_dump at boot time.  Kdump can use
this on cmdline (phyp_dump=0) to disable phyp-dump during boot when
enabling itself.  This will ensure only one dumping mechanism is active
at any given time.

Signed-off-by: Manish Ahuja <mahuja@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-03-26 08:44:07 +11:00
Manish Ahuja
6ac26c8a7e [POWERPC] pseries: phyp dump: Reserve and release memory
Initial patch for reserving memory in early boot, and freeing it
later.  If the previous boot had ended with a crash, the reserved
memory would contain a copy of the crashed kernel data.

Signed-off-by: Manish Ahuja <mahuja@us.ibm.com>
Signed-off-by: Linas Vepstas <linasvepstas@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-03-26 08:44:06 +11:00