Commit graph

4512 commits

Author SHA1 Message Date
Benjamin Herrenschmidt
058c78f4ba powerpc: Use new printk extension %pS to print symbols on oops
This changes the oops and backtrace code to use the new %pS
printk extension to print out symbols rather than manually
calling print_symbol.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-09 16:30:44 +10:00
Mark Nelson
3a4c6f0b15 powerpc: move device_to_mask() to dma-mapping.h
Move device_to_mask() to dma-mapping.h because we need to use it from
outside dma_64.c in a later patch.

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-09 16:30:44 +10:00
Mark Nelson
7e5f810503 powerpc/cell: cell_dma_dev_setup_iommu() return the iommu table
Make cell_dma_dev_setup_iommu() return a pointer to the struct iommu_table
(or NULL if no table can be found) rather than putting this pointer into
dev->archdata.dma_data (let the caller do that), and rename this function
to cell_get_iommu_table() to reflect this change.

This will allow us to get the iommu table for a device that doesn't have
the table in the archdata.

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-09 16:30:43 +10:00
Mark Nelson
3affedc4e1 powerpc/dma: implement new dma_*map*_attrs() interfaces
Update powerpc to use the new dma_*map*_attrs() interfaces. In doing so
update struct dma_mapping_ops to accept a struct dma_attrs and propagate
these changes through to all users of the code (generic IOMMU and the
64bit DMA code, and the iseries and ps3 platform code).

The old dma_*map_*() interfaces are reimplemented as calls to the
corresponding new interfaces.

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-09 16:30:43 +10:00
Mark Nelson
c8692362db powerpc/dma: Add struct iommu_table argument to iommu_map_sg()
Make iommu_map_sg take a struct iommu_table. It did so before commit
740c3ce667 (iommu sg merging: ppc: make
iommu respect the segment size limits).

This stops the function looking in the archdata.dma_data for the iommu
table because in the future it will be called with a device that has
no table there.

This also has the nice side effect of making iommu_map_sg() match the
other map functions.

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-09 16:30:43 +10:00
Maxim Shchetynin
fabb657005 powerpc/spufs: add atomic busy_spus counter to struct cbe_spu_info
As nr_active counter includes also spus waiting for syscalls to return
we need a seperate counter that only counts spus that are currently running
on spu side. This counter shall be used by a cpufreq governor that targets
a frequency dependent from the number of running spus.

Signed-off-by: Christian Krafft <krafft@de.ibm.com>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-09 16:30:42 +10:00
Geoff Levand
88b90c96b7 powerpc/ps3: Quiet system bus match output
Reduce the output verbosity of ps3_system_bus_match().

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-09 16:30:42 +10:00
Jeremy Kerr
2c3e47871d powerpc/spufs: only add ".ctx" file with "debug" mount option
Currently, the .ctx debug file in spu context directories is always
present.

We'd prefer to prevent users from relying on this file, so add a
"debug" mount option to spufs. The .ctx file will only be added to
the context directories when this option is present.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-07-09 10:13:41 +10:00
Jeremy Kerr
6f7dde812d powerpc/spufs: add sizes for context files
Populate the size member of a few context files. Leave out files that
have different semantics with read vs mmap, or contain a
variable-length hex string.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-07-09 10:13:41 +10:00
Jeremy Kerr
23d893f51c powerpc/spufs: allow spufs files to specify sizes
Currently, spufs never specifies the i_size for the files in context
directories, so stat() always reports 0-byte files.

This change adds allows the spufs_dir_(nosched_)contents arrays to
specify a file size. This allows stat() to report correct file sizes,
and makes SEEK_END work.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-07-09 10:13:40 +10:00
Jeremy Kerr
87ff6090bf powerpc/spufs: avoid magic numbers for mapping sizes
Use a set of #defines for the size of context mappings, instead of
magic numbers.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-07-09 10:13:40 +10:00
Luke Browning
2442a8ba5a powerpc/spufs: don't extend time time slice if context is not in spu_run
An spu context shouldn't get an extra tick if the time slice code
couldn't find something else to run. This means contexts that are not
within spu_run (ie, SPU_SCHED_SPU_RUN is cleared) will not receive
extra ticks while we have no other contexts waiting.

Signed-off-by: Luke Browning <lukebrowning@us.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-07-09 10:13:40 +10:00
Luke Browning
46deed69b3 powerpc/spufs: provide context debug file
Add a ctxt file to spufs that shows spu context information that is used
in scheduling. This info can be used for debugging spufs scheduler
issues, and to isolate between application and spufs problems as it
shows a lot of state such as priorities and dispatch counts.

This file contains internal spufs state and is subject to change at any
time, and therefore no applications should depend on it.  The file is
intended for the use of spufs kernel developers.

Signed-off-by: Luke Browning <lukebrowning@us.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
2008-07-09 10:13:40 +10:00
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
Nathan Fontenot
3c3f67eafa powerpc/pseries: Update the device tree correctly for drconf memory add/remove
This updates the device tree manipulation routines so that memory
add/remove of lmbs represented under the
ibm,dynamic-reconfiguration-memory node of the device tree invokes the
hotplug notifier chain.

This change is needed because of the change in the way memory is
represented under the ibm,dynamic-reconfiguration-memory node.  All lmbs
are described in the ibm,dynamic-memory property instead of having a
separate node for each lmb as in previous device tree layouts.  This
requires the update_node() routine to check for updates to the
ibm,dynamic-memory property and invoke the hotplug notifier chain.

This also updates the pseries hotplug notifier to be able to gather information
for lmbs represented under the ibm,dynamic-reconfiguration-memory node and
have the lmbs added/removed.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:16 +10:00
Nathan Fontenot
92ecd1790b powerpc/pseries: Use base address to derive starting page frame number
Use the base address of the lmb to derive the starting page frame number
instead of trying to extract it from the drc index of the lmb.  The drc
index should not be used for this as it will, and did, break.

Until this point, systems that have had memory represented in the device
tree with a node for each lmb the drc index would (luckily) closely
track the base address of the lmb.  For example a lmb with a drc index
of 8000000a would have a base address of a0000000.  This correlation
allowed the current code to derive the starting page frame number from
the drc inddex

Device tree layouts where lmbs are represented under the
ibm,dynamic-reconfiguration-memory node in the ibm,dynamic-memory
property do not have this correlation between the drc index and base
address of the lmb.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:15 +10:00
Nathan Fontenot
4b6e805e4a powerpc/pseries: Allow phandle to be specified in formats other than decimal
Allow the phandle passed to the /proc/ppc64/ofdt file to be specified
in formats other than decimal.  This allows us to easily specify phandle
values in hex that would otherwise appear as negative integers.

This is an issue on systems where the value of
/proc/device-tree/ibm,dynamic-reconfiguration-memory.ibm,phandle is
fffffff9.  Having to pass this to the ofdt file as a string results in
a large negative number, and simple_strtoul() does not handle negative
numbers.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:14 +10:00
Michael Neuling
138fc1ee06 powerpc: Remove old dump_task_* functions
Since Roland's ptrace cleanup starting with commit
f65255e8d5 ("[POWERPC] Use user_regset
accessors for FP regs"), the dump_task_* functions are no longer being
used.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:13 +10:00
Michael Neuling
6a274c08f2 powerpc: Clean up copy_to/from_user for vsx and fpr
This merges and cleans up some of the ugly copy/to from user code
which is required for the new fpr and vsx layout in the thread_struct.

Also fixes some hard coded buffer sizes and removes a redundant
fpr_flush_to_thread.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:11 +10:00
Kumar Gala
2d1b202762 powerpc: Fixup lwsync at runtime
To allow for a single kernel image on e500 v1/v2/mc we need to fixup lwsync
at runtime.  On e500v1/v2 lwsync causes an illop so we need to patch up
the code.  We default to 'sync' since that is always safe and if the cpu
is capable we will replace 'sync' with 'lwsync'.

We introduce CPU_FTR_LWSYNC as a way to determine at runtime if this is
needed.  This flag could be moved elsewhere since we dont really use it
for the normal CPU_FTR purpose.

Finally we only store the relative offset in the fixup section to keep it
as small as possible rather than using a full fixup_entry.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:10 +10:00
Kumar Gala
5888da1876 powerpc: Fix building of feature-fixup tests on ppc32
We need to use PPC_LCMPI otherwise we get compile errors like:

arch/powerpc/lib/feature-fixups-test.S: Assembler messages:
arch/powerpc/lib/feature-fixups-test.S:142: Error: Unrecognized opcode: `cmpdi'
arch/powerpc/lib/feature-fixups-test.S:149: Error: Unrecognized opcode: `cmpdi'
arch/powerpc/lib/feature-fixups-test.S:164: Error: Unrecognized opcode: `cmpdi'

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:09 +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
Michael Neuling
f3e909c275 powerpc: Update for VSX core file and ptrace
This correctly hooks the VSX dump into Roland McGrath core file
infrastructure.  It adds the VSX dump information as an additional elf
note in the core file (after talking more to the tool chain/gdb guys).
This also ensures the formats are consistent between signals, ptrace
and core files.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 14:47:09 +10:00
Michael Neuling
436db693c4 powerpc: Fix compile error for CONFIG_VSX
Fix compile error when CONFIG_VSX is enabled.

arch/powerpc/kernel/signal_64.c: In function 'restore_sigcontext':
arch/powerpc/kernel/signal_64.c:241: error: 'i' undeclared (first use in this function)

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 14:47:07 +10:00
Stephen Rothwell
fcbc5a976b powerpc: Explicitly copy elements of pt_regs
Gcc 4.3 produced this warning:

arch/powerpc/kernel/signal_64.c: In function 'restore_sigcontext':
arch/powerpc/kernel/signal_64.c:161: warning: array subscript is above array bounds

This is caused by us copying to aliases of elements of the pt_regs
structure.  Make those explicit.

This adds one extra __get_user and unrolls a loop.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:59 +10:00
Bernhard Walle
3420b5daff powerpc: Remove experimental status of kdump on 64-bit powerpc
This removes the experimental status of kdump on PPC64.  kdump is on
PPC64 now since more than one year and it has proven to be stable.

Signed-off-by: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:57 +10:00
Andrew Lewis
03d70617b8 powerpc: Prevent memory corruption due to cache invalidation of unaligned DMA buffer
On PowerPC processors with non-coherent cache architectures the DMA
subsystem calls invalidate_dcache_range() before performing a DMA read
operation.  If the address and length of the DMA buffer are not aligned
to a cache-line boundary this can result in memory outside of the DMA
buffer being invalidated in the cache.  If this memory has an
uncommitted store then the data will be lost and a subsequent read of
that address will result in an old value being returned from main memory.

Only when the DMA buffer starts on a cache-line boundary and is an exact
mutiple of the cache-line size can invalidate_dcache_range() be called,
otherwise flush_dcache_range() must be called.  flush_dcache_range()
will first flush uncommitted writes, and then invalidate the cache.

Signed-off-by: Andrew Lewis <andrew-lewis at netspace.net.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:54 +10:00
Kumar Gala
9d4ae9fc92 powerpc/bootwrapper: Pad .dtb by default
Since most bootloaders or wrappers tend to update or add some information
to the .dtb they a handled they need some working space to do that in.

By default add 1K of padding via a default setting of DTS_FLAGS.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:53 +10:00
Michael Neuling
96d5b52c84 powerpc: Add CONFIG_VSX config option
Add CONFIG_VSX config build option.  Must compile with POWER4, FPU and ALTIVEC.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:51 +10:00
Michael Neuling
ce48b21007 powerpc: Add VSX context save/restore, ptrace and signal support
This patch extends the floating point save and restore code to use the
VSX load/stores when VSX is available.  This will make FP context
save/restore marginally slower on FP only code, when VSX is available,
as it has to load/store 128bits rather than just 64bits.

Mixing FP, VMX and VSX code will get constant architected state.

The signals interface is extended to enable access to VSR 0-31
doubleword 1 after discussions with tool chain maintainers.  Backward
compatibility is maintained.

The ptrace interface is also extended to allow access to VSR 0-31 full
registers.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:50 +10:00
Michael Neuling
72ffff5b17 powerpc: Add VSX assembler code macros
This adds the macros for the VSX load/store instruction as most
binutils are not going to support this for a while.

Also add VSX register save/restore macros and vsr[0-63] register definitions.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:48 +10:00
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
Michael Neuling
c6e6771b87 powerpc: Introduce VSX thread_struct and CONFIG_VSX
The layout of the new VSR registers and how they overlap on top of the
legacy FPR and VR registers is:

                   VSR doubleword 0               VSR doubleword 1
          ----------------------------------------------------------------
  VSR[0]  |             FPR[0]            |                              |
          ----------------------------------------------------------------
  VSR[1]  |             FPR[1]            |                              |
          ----------------------------------------------------------------
          |              ...              |                              |
          |              ...              |                              |
          ----------------------------------------------------------------
  VSR[30] |             FPR[30]           |                              |
          ----------------------------------------------------------------
  VSR[31] |             FPR[31]           |                              |
          ----------------------------------------------------------------
  VSR[32] |                             VR[0]                            |
          ----------------------------------------------------------------
  VSR[33] |                             VR[1]                            |
          ----------------------------------------------------------------
          |                              ...                             |
          |                              ...                             |
          ----------------------------------------------------------------
  VSR[62] |                             VR[30]                           |
          ----------------------------------------------------------------
  VSR[63] |                             VR[31]                           |
          ----------------------------------------------------------------

VSX has 64 128bit registers.  The first 32 regs overlap with the FP
registers and hence extend them with and additional 64 bits.  The
second 32 regs overlap with the VMX registers.

This commit introduces the thread_struct changes required to reflect
this register layout.  Ptrace and signals code is updated so that the
floating point registers are correctly accessed from the thread_struct
when CONFIG_VSX is enabled.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:46 +10:00
Michael Neuling
6f3d8e6947 powerpc: Make load_up_fpu and load_up_altivec callable
Make load_up_fpu and load_up_altivec callable so they can be reused by
the VSX code.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:45 +10:00
Michael Neuling
10e343925a powerpc: Move altivec_unavailable
Move the altivec_unavailable code, to make room at 0xf40 where the
vsx_unavailable exception will be.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:44 +10:00
Michael Neuling
9c75a31c35 powerpc: Add macros to access floating point registers in thread_struct.
We are going to change where the floating point registers are stored
in the thread_struct, so in preparation add some macros to access the
floating point registers.  Update all code to use these new macros.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:43 +10:00
Michael Neuling
9e7511861c powerpc: Fix MSR setting in 32 bit signal code
If we set the SPE MSR bit in save_user_regs we can blow away the VEC
bit.  This doesn't matter in reality as they are in fact the same bit
but looks bad.

Also, when we add VSX in a later patch, we need to be able to set two
separate MSR bits here.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:42 +10:00
Tony Breeds
9b09c6d909 powerpc: Change the default link address for pSeries zImage kernels
Currently we set the start of the .text section to be 4Mb for pSeries.
In situations where the zImage is > 8Mb we'll fail to boot (due to
overlapping with OF).  Move .text in a zImage from 4MB to 64MB
(well past OF).

We still will not be able to load large zImage unless we also move OF,
to that end, add a note to the zImage ELF to move OF to 32Mb.  If this
is the very first kernel booted then we'll need to move OF manually by
setting real-base.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:32 +10:00
Michael Ellerman
c230328def powerpc: Use an alternative feature section in entry_64.S
Use an alternative feature section in _switch. There are three cases
handled here, either we don't have an SLB, in which case we jump over the
entire code section, or if we do we either do or don't have 1TB segments.

Boot tested on Power3, Power5 and Power5+.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:31 +10:00
Michael Ellerman
362e7701fd powerpc: Add self-tests of the feature fixup code
This commit adds tests of the feature fixup code, they are run during
boot if CONFIG_FTR_FIXUP_SELFTEST=y. Some of the tests manually invoke
the patching routines to check their behaviour, and others use the
macros and so are patched during the normal patching done during boot.

Because we have two sets of macros with different names, we use a macro
to generate the test of the macros, very niiiice.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:30 +10:00
Michael Ellerman
9b1a735de6 powerpc: Add logic to patch alternative feature sections
This commit adds the logic to patch alternative sections.  This is fairly
straightforward, except for branches.  Relative branches that jump from
inside the else section to outside of it need to be translated as they're
moved, otherwise they will jump to the wrong location.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:29 +10:00
Michael Ellerman
fac23fe4be powerpc: Introduce infrastructure for feature sections with alternatives
The current feature section logic only supports nop'ing out code, this means
if you want to choose at runtime between instruction sequences, one or both
cases will have to execute the nop'ed out contents of the other section, eg:

BEGIN_FTR_SECTION
	or	1,1,1
END_FTR_SECTION_IFSET(FOO)
BEGIN_FTR_SECTION
	or	2,2,2
END_FTR_SECTION_IFCLR(FOO)

and the resulting code will be either,

	or	1,1,1
	nop

or,
	nop
	or	2,2,2

For small code segments this is fine, but for larger code blocks and in
performance criticial code segments, it would be nice to avoid the nops.
This commit starts to implement logic to allow the following:

BEGIN_FTR_SECTION
	or	1,1,1
FTR_SECTION_ELSE
	or	2,2,2
ALT_FTR_SECTION_END_IFSET(FOO)

and the resulting code will be:

	or	1,1,1
or,
	or	2,2,2

We achieve this by extending the existing FTR macros. The current feature
section semantic just becomes a special case, ie. if the else case is empty
we nop out the default case.

The key limitation is that the size of the else case must be less than or
equal to the size of the default case. If the else case is smaller the
remainder of the section is nop'ed.

We let the linker put the else case code in with the rest of the text,
so that relative branches from the else case are more likley to link,
this has the disadvantage that we can't free the unused else cases.

This commit introduces the required macro and linker script changes, but
does not enable the patching of the alternative sections.

We also need to update two hand-made section entries in reg.h and timex.h

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:28 +10:00
Michael Ellerman
51c52e8669 powerpc: Split out do_feature_fixups() from cputable.c
The logic to patch CPU feature sections lives in cputable.c, but these days
it's used for CPU features as well as firmware features.  Move it into
it's own file for neatness and as preparation for some additions.

While we're moving the code, we pull the loop body logic into a separate
routine, and remove a comment which doesn't apply anymore.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:24 +10:00
Michael Ellerman
b7bcda631e powerpc: Add PPC_NOP_INSTR, a hash define for the preferred nop instruction
A bunch of code has hard-coded the value for a "nop" instruction, it
would be nice to have a #define for it.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:23 +10:00
Michael Ellerman
ae0dc73625 powerpc: Add tests of the code patching routines
Add tests of the existing code patching routines, as well as the new
routines added in the last commit.  The self-tests are run late in boot
when CONFIG_CODE_PATCHING_SELFTEST=y, which depends on DEBUG_KERNEL=y.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:22 +10:00
Michael Ellerman
411781a290 powerpc: Add new code patching routines
This commit adds some new routines for patching code, which will be used
in a following commit.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:21 +10:00
Michael Ellerman
053a858efa powerpc: Make create_branch() return errors if the branch target is too large
If you pass a target value to create_branch() which is more than 32MB - 4,
or - 32MB away from the branch site, then it's impossible to create an
immediate branch.  The current code doesn't check, which will lead to us
creating a branch to somewhere else - which is bad.

For code that cares to check we return 0, which is easy to check for, and
for code that doesn't at least we'll be creating an illegal instruction,
rather than a branch to some random address.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:19 +10:00
Michael Ellerman
e7a57273c6 powerpc: Allow create_branch() to return errors
Currently create_branch() creates a branch instruction for you, and
patches it into the call site.  In some circumstances it would be nice
to be able to create the instruction and patch it later, and also some
code might want to check for errors in the branch creation before
doing the patching.  A future commit will change create_branch() to
check for errors.

For callers that don't care, replace create_branch() with
patch_branch(), which just creates the branch and patches it directly.

While we're touching all the callers, change to using unsigned int *,
as this seems to match usage better.  That allows (and requires) us to
remove the volatile in the definition of vector in powermac/smp.c and
mpc86xx_smp.c, that's correct because now that we're passing vector as
an unsigned int * the compiler knows that it's value might change
across the patch_branch() call.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:19 +10:00
Michael Ellerman
aaddd3eaca powerpc: Move code patching code into arch/powerpc/lib/code-patching.c
We currently have a few routines for patching code in asm/system.h, because
they didn't fit anywhere else. I'd like to clean them up a little and add
some more, so first move them into a dedicated C file - they don't need to
be inlined.

While we're moving the code, drop create_function_call(), it's intended
caller never got merged and will be replaced in future with something
different.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:18 +10:00