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: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Add a VSX CPU feature.  Also add code to detect if VSX is available
from the device tree.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NJoel Schopp <jschopp@austin.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Make load_up_fpu and load_up_altivec callable so they can be reused by
the VSX code.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Move the altivec_unavailable code, to make room at 0xf40 where the
vsx_unavailable exception will be.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Ellerman <michael@ellerman.id.au>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Ellerman <michael@ellerman.id.au>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Ellerman <michael@ellerman.id.au>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Acked-by: NJon Loeliger <jdl@freescale.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

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: NMichael Ellerman <michael@ellerman.id.au>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Refactor common code between ppc32 and ppc64 module handling into a
shared filed.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Add the bits to the architecture-vec so that ibm,client-architecture
lets the firmware know we support the 2.06 architecture.
Signed-off-by: NJoel Schopp <jschopp@austin.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Add an entry for Power7 architected mode and add "(raw)" to Power7 raw
mode to distinguish it more clearly.
Signed-off-by: NJoel Schopp <jschopp@austin.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Add a cputable entry for the POWER7 processor.

Also tell firmware that we know about POWER7.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NJoel Schopp <jschopp@austin.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

There are now two potential callers of machine_crash_shutdown,
so increase the limit accordingly.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This patch is based on work done by Madhvesh. R. Sulibhavi back in
March 2007.

We refactor some of the single step handling since it differs between
"classic" and "booke" powerpc cores.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

* Mark __flush_icache_range as a function that can't be probed since its
  used by the kprobe code.

* Fix an issue with single stepping and async exceptions.  We need to
  ensure that we dont get an async exception (external, decrementer, etc)
  while we are attempting to single step the probe point.

  Added a check to ensure we only handle a single step if its really
  intended for the instruction in question.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

If we have an L2CSR register (e500mc) we need to flush the L2 before going
to nap.  We use the HW flush mechanism provided in that register.

The code reuses the CPU_FTR_604_PERF_MON bit as it is no longer used by
any code in the kernel.  Additionally we didn't reuse the exist L2CR
feature bit as this is intended for the 7xxx L2CR register and L2CSR
is part of the new Freescale "Book-E" registers.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

The e500 core enter DOZE/NAP power-saving modes when the core go to
cpu_idle routine.

The power management default running mode is DOZE, If the user

echo 1 > /proc/sys/kernel/powersave-nap

the system will change to NAP running mode.
Signed-off-by: NDave Liu <daveliu@freescale.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

KAMEZAWA Hiroyuki and Oleg Nesterov point out that since the commit
557ed1fa ("remove ZERO_PAGE") removed
the ZERO_PAGE from the VM mappings, any users of get_user_pages() will
generally now populate the VM with real empty pages needlessly.

We used to get the ZERO_PAGE when we did the "handle_mm_fault()", but
since fault handling no longer uses ZERO_PAGE for new anonymous pages,
we now need to handle that special case in follow_page() instead.

In particular, the removal of ZERO_PAGE effectively removed the core
file writing optimization where we would skip writing pages that had not
been populated at all, and increased memory pressure a lot by allocating
all those useless newly zeroed pages.

This reinstates the optimization by making the unmapped PTE case the
same as for a non-existent page table, which already did this correctly.

While at it, this also fixes the XIP case for follow_page(), where the
caller could not differentiate between the case of a page that simply
could not be used (because it had no "struct page" associated with it)
and a page that just wasn't mapped.

We do that by simply returning an error pointer for pages that could not
be turned into a "struct page *".  The error is arbitrarily picked to be
EFAULT, since that was what get_user_pages() already used for the
equivalent IO-mapped page case.

[ Also removed an impossible test for pte_offset_map_lock() failing:
  that's not how that function works ]
Acked-by: NOleg Nesterov <oleg@tv-sign.ru>
Acked-by: NNick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The new e500mc core from Freescale is based on the e500v2 but with the
following changes:

* Supports only the Enhanced Debug Architecture (DSRR0/1, etc)
* Floating Point
* No SPE
* Supports lwsync
* Doorbell Exceptions
* Hypervisor
* Cache line size is now 64-bytes (e500v1/v2 have a 32-byte cache line)
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

A recent commit added support for the new 440x6 and 464 cores that have the
added WL1, IL1I, IL1D, IL2I, and ILD2 bits for the caching attributes in the
TLBs.  The new bits were cleared in the finish_tlb_load function, however a
similar bit of code was missed in the DataStorage interrupt vector.
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

There are no in-tree uses of the export any more and in linux-next there
is a change that exports it globally which causes warnings:

WARNING: vmlinux: 'console_drivers' exported twice. Previous export was in vmlinux

and in one case (mpc85xx_defconfig) a build error:

kernel/built-in.o: In function `__crc_console_drivers':
(*ABS*+0x1eb0e6f5): multiple definition of `__crc_console_drivers'

So remove the export now.  Also, there is no longer any need to include
linux/console.h.
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

GCC 4.4.x looks to be adding support for generating out-of-line register
saves/restores based on:

http://gcc.gnu.org/ml/gcc-patches/2008-04/msg01678.html

This breaks the kernel if we enable CONFIG_CC_OPTIMIZE_FOR_SIZE.  To fix
this we add the use the save/restore code from gcc and simplified it down
for our needs (integer only).

Additionally, we have to link this code into each module.  The other
solution was to add EXPORT_SYMBOL() which meant going through the
trampoline which seemed nonsensical for these out-of-line routines.

Finally, we add some checks to prom_init_check.sh to ignore the
out-of-line save/restore functions.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

debugfs_create_file() returns a non-NULL (non-zero) value in case of
success, not a NULL value.

This fixes this non-critical boot-time debugging error message:

[    1.316386] calling  irq_debugfs_init+0x0/0x50
[    1.316399] initcall irq_debugfs_init+0x0/0x50 returned -12 after 0 msecs
[    1.316411] initcall irq_debugfs_init+0x0/0x50 returned with error code -12
Signed-off-by: NEmil Medve <Emilian.Medve@Freescale.com>
Acked-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

This reverts commit acb0142b.

AMCC has indicated that the PPC 460GT does have FPU support.  This
revert enables the FPU for those chips again.
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

When I changed irq_alloc_host() to take an of_node
(52964f87: "Add an optional
device_node pointer to the irq_host"), I botched the reference
counting semantics.

Stephen pointed out that it's irq_alloc_host()'s business if
it needs to take an additional reference to the device_node,
the caller shouldn't need to care.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This eliminates this minor boot-time debugging error message:

[    1.316451] calling  add_pcspkr+0x0/0x84
[    1.316478] initcall add_pcspkr+0x0/0x84 returned -19 after 0 msecs
Signed-off-by: NEmil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

During the next merge window, pci_name()'s return value will become
const, so use the new dev_set_name() instead to avoid the warning (from
linux-next):

arch/powerpc/kernel/pci_64.c: In function 'of_create_pci_dev':
arch/powerpc/kernel/pci_64.c:193: warning: passing argument 1 of 'sprintf' discards qualifiers from pointer target type

Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

When building a signal or a ucontext, we can incorrectly set the MSR_VEC
bit of the kernel pt_regs->msr before returning to userspace if the task
-ever- used VMX.

This can lead to funny result if that stack used it in the past, then
"lost" it (ie. it wasn't enabled after a context switch for example)
and then called get_context.  It can end up with VMX enabled and the
registers containing values from some other task.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

On machines with more than one exception level any system register that
might be modified by the "normal" exception level needs to be saved and
restored on taking a higher level exception.  We already are saving
and restoring ESR and DEAR.

For critical level add SRR0/1.
For debug level add CSRR0/1 and SRR0/1.
For machine check level add DSRR0/1, CSRR0/1, and SRR0/1.

On FSL Book-E parts we always save/restore the MAS registers for critical,
debug, and machine check level exceptions.  On 44x we always save/restore
the MMUCR.

Additionally, we save and restore the ksp_limit since we have to adjust it
for each exception level.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Acked-by: NPaul Mackerras <paulus@samba.org>