Commit Graph

98697 Commits

Author SHA1 Message Date
Josh Boyer beae4c03c0 Merge branch 'virtex-for-2.6.27' of git://git.secretlab.ca/git/linux-2.6-virtex into 4xx-next 2008-07-09 13:35:16 -04:00
Grant Likely 9fde9bdd30 powerpc/440: Convert Virtex ML507 device tree to dts-v1
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2008-07-09 10:56:11 -06:00
Grant Likely c356aa456e powerpc/bootwrapper: Allow user to specify additional default targets
It is inconvenient to add additional default targets to the bootwrapper
Makefile for each new board supported which just needs a different dts
file.  This change allows the defconfig to specify additional build
targets.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-07-09 09:41:52 -06:00
Grant Likely 1d46e379aa powerpc/bootwrapper: add missing bit of simpleImage target
The wrapper script is missing the bits needed for building generic
simpleImage targets (targets which don't depend on any particular
firmware interface and retrieve all their data from the device tree).

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2008-07-04 00:59:37 -06:00
Grant Likely 70bf0333d7 powerpc/bootwrapper: Add documentation of boot wrapper targets
There have been many questions on and off the mailing list about how
exactly the bootwrapper is used for embedded targets.  Add some
documentation and help text to try and clarify the system.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2008-07-04 00:59:03 -06:00
John Linn 94ec359e45 powerpc/virtex: add defconfig for virtex 5 platforms
This defconfig file is specific to Xilinx Virtex 5 FXT platform.

Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2008-07-04 00:59:02 -06:00
John Linn 23e7237e09 powerpc/virtex: add Xilinx 440 cpu to the cputable
Updates the cputable to include the 440 processor found in the
Xilinx Virtex5 FXT FPGA.

Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2008-07-04 00:59:02 -06:00
John Linn 39fd0e92b3 powerpc/virtex: add Xilinx Virtex 5 ppc440 platform support
Support for the Xilinx Virtex5 FXT 440 is being added.

Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2008-07-04 00:59:02 -06:00
John Linn d58577d8f3 powerpc/virtex: Fix booting of Xilinx FPGAs with 16550 for 405 and 440
The following changes add processing to initialize the Xilinx 16550 UART
in the boot wrapper for Virtex targets without firmware.  Normally the
boot wrapper assumes that the serial port has already been initialized by
firmware.

The wrapper was also modified to add the 440 build.

Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2008-07-04 00:58:59 -06:00
John Linn dc568ec490 powerpc/virtex: add dts file for ML507 reference design
This new file adds support for the ML507 reference design.  The ML507
uses the Virtex 5 FXT FPGA which embeds a ppc440 core.

Signed-off-by: John Linn <john.linn@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2008-07-04 00:57:59 -06:00
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
Michael Neuling e17a2565bf powerpc: Fix compile warning in init_thread
Currently we get this warning:
arch/powerpc/kernel/init_task.c:33: warning: missing braces around initializer
arch/powerpc/kernel/init_task.c:33: warning: (near initialization for 'init_task.thread.fpr[0]')

This fixes it.

Noticed by Stephen Rothwell.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-03 16:58:08 +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
Eric B Munson a91a03ee31 powerpc: Keep 3 high personality bytes across exec
Currently when a 32 bit process is exec'd on a powerpc 64 bit host the
value in the top three bytes of the personality is clobbered.  patch
adds a check in the SET_PERSONALITY macro that will carry all the
values in the top three bytes across the exec.

These three bytes currently carry flags to disable address randomisation,
limit the address space, force zeroing of an mmapped page, etc.  Should an
application set any of these bits they will be maintained and honoured on
homogeneous environment but discarded and ignored on a heterogeneous
environment.  So if an application requires all mmapped pages to be initialised
to zero and a wrapper is used to setup the personality and exec the target,
these flags will remain set on an all 32 or all 64 bit envrionment, but they
will be lost in the exec on a mixed 32/64 bit environment.  Losing these bits
means that the same application would behave differently in different
environments.  Tested on a POWER5+ machine with 64bit kernel and a mixed
64/32 bit user space.

Signed-off-by: Eric B Munson <ebmunson@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 14:47:02 +10:00
Bart Van Assche 89b5810f6e powerpc: Make sure that include/asm-powerpc/spinlock.h does not trigger compilation warnings
When compiling kernel modules for ppc that include <linux/spinlock.h>,
gcc prints a warning message every time it encounters a function
declaration where the inline keyword appears after the return type.
This makes sure that the order of the inline keyword and the return
type is as gcc expects it.  Additionally, the __inline__ keyword is
replaced by inline, as checkpatch expects.

Signed-off-by: Bart Van Assche <bart.vanassche@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:29:00 +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
Andy Whitcroft 016b33c495 powerpc: Add 64 bit version of huge_ptep_set_wrprotect
The implementation of huge_ptep_set_wrprotect() directly calls
ptep_set_wrprotect() to mark a hugepte write protected.  However this
call is not appropriate on ppc64 kernels as this is a small page only
implementation.  This can lead to the hash not being flushed correctly
when a mapping is being converted to COW, allowing processes to continue
using the original copy.

Currently huge_ptep_set_wrprotect() unconditionally calls
ptep_set_wrprotect().  This is fine on ppc32 kernels as this call is
generic.  On 64 bit this is implemented as:

	pte_update(mm, addr, ptep, _PAGE_RW, 0);

On ppc64 this last parameter is the page size and is passed directly on
to hpte_need_flush():

	hpte_need_flush(mm, addr, ptep, old, huge);

And this directly affects the page size we pass to flush_hash_page():

	flush_hash_page(vaddr, rpte, psize, ssize, 0);

As this changes the way the hash is calculated we will flush the wrong
pages, potentially leaving live hashes to the original page.

Move the definition of huge_ptep_set_wrprotect() to the 32/64 bit specific
headers.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-07-01 11:28:56 +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 c1137c37a9 powerpc: Consolidate feature fixup macros for 64/32 bit
Currently we have three versions of MAKE_FTR_SECTION_ENTRY(), the macro that
generates a feature section entry.  There is 64bit version, a 32bit version
and version for 32bit code built with a 64bit kernel.

Rather than triplicating (?) the MAKE_FTR_SECTION_ENTRY() logic, we can
move the 64bit/32bit differences into separate macros, and then only have
one version of MAKE_FTR_SECTION_ENTRY().

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 11:28:26 +10:00
Michael Ellerman c5157e587b powerpc: Consolidate CPU and firmware feature fixup macros
The CPU and firmware feature fixup macros are currently spread across
three files, firmware.h, cputable.h and asm-compat.h.  Consolidate them
into their own file, feature-fixups.h

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 11:28:25 +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