Commit Graph

15 Commits

Author SHA1 Message Date
Neil Campbell
bb7f20b1c6 powerpc: Handle VSX alignment faults correctly in little-endian mode
This patch fixes the handling of VSX alignment faults in little-endian
mode (the current code assumes the processor is in big-endian mode).

The patch also makes the handlers clear the top 8 bytes of the register
when handling an 8 byte VSX load.

This is based on 2.6.32.

Signed-off-by: Neil Campbell <neilc@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-18 14:55:43 +11:00
Anton Blanchard
eecff81d1f powerpc: Create PPC_WARN_ALIGNMENT to match PPC_WARN_EMULATED
perf_event wants a separate event for alignment and emulation faults,
so create another emulation event.  This will make it easy to hook in
perf_event at one spot.

We pass in regs which will be required for these events.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2009-10-28 16:13:03 +11:00
Geert Uytterhoeven
80947e7c99 powerpc: Keep track of emulated instructions
If CONFIG_PPC_EMULATED_STATS is enabled, make available counters for the
various classes of emulated instructions under
/sys/kernel/debug/powerpc/emulated_instructions/ (assumed debugfs is mounted on
/sys/kernel/debug).  Optionally (controlled by
/sys/kernel/debug/powerpc/emulated_instructions/do_warn), rate-limited warnings
can be printed to the console when instructions are emulated.

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-05-21 15:44:26 +10:00
Michael Neuling
553631e25f powerpc: Fix load/store float double alignment handler
When we introduced VSX, we changed the way FPRs are stored in the
thread_struct.  Unfortunately we missed the load/store float double
alignment handler code when updating how we access FPRs in the
thread_struct.

Below fixes this and merges the little/big endian case.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-23 15:53:05 +11:00
Michael Neuling
545bba1824 powerpc: Add alignment handler for new lfiwzx instruction
lfiwzx is a new floating point load instruction in 2.06 that needs an
alignment handler for Linux.

Turns out to be the worlds easiest handler to add.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-23 15:53:04 +11:00
Michael Neuling
26456dcfb8 powerpc/vsx: Fix VSX alignment handler for regs 32-63
Fix the VSX alignment handler for VSX registers > 32.  32-63 are stored
in the VMX part of the thread_struct not the FPR part.

Signed-off-by: Michael Neuling <mikey@neuling.org>
CC: stable@kernel.org (2.6.27 & .28 please)
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-13 16:37:45 +11:00
Michael Neuling
78fbc824ed powerpc: Fix uninitialised variable in VSX alignment code
This fixes an uninitialised variable in the VSX alignment code.  It can
cause warnings from GCC (noticed with gcc-4.1.1).  Gcc is actually
correct in this instance, and this bug could cause the alignment
interrupt handler to send a SIGSEGV to the process on a legitimate
access.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-09-03 20:53:14 +10:00
Michael Neuling
cd6f37be7f powerpc: Add VSX load/store alignment exception handler
VSX loads and stores will take an alignment exception when the address
is not on a 4 byte boundary.

This add support for these alignment exceptions and will emulate the
requested load or store.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-15 12:29:25 +10:00
Michael Neuling
b887ec620a powerpc: remove unused variable in emulate_fp_pair
regs is not used in emulate_fp_pair so remove it.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2008-07-09 16:30:47 +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
Kumar Gala
26caeb2ee1 [POWERPC] Handle alignment faults on SPE load/store instructions
This adds code to handle alignment traps generated by the following
SPE (signal processing engine) load/store instructions, by emulating
the instruction in the kernel (as is done for other instructions that
generate alignment traps):

evldd[x]         Vector Load Double Word into Double Word [Indexed]
evldw[x]         Vector Load Double into Two Words [Indexed]
evldh[x]         Vector Load Double into Four Half Words [Indexed]
evlhhesplat[x]   Vector Load Half Word into Half Words Even and Splat [Indexed]
evlhhousplat[x]  Vector Load Half Word into Half Word Odd Unsigned and Splat [Indexed]
evlhhossplat[x]  Vector Load Half Word into Half Word Odd Signed and Splat [Indexed]
evlwhe[x]        Vector Load Word into Two Half Words Even [Indexed]
evlwhou[x]       Vector Load Word into Two Half Words Odd Unsigned (zero-extended) [Indexed]
evlwhos[x]       Vector Load Word into Two Half Words Odd Signed (with sign extension) [Indexed]
evlwwsplat[x]    Vector Load Word into Word and Splat [Indexed]
evlwhsplat[x]    Vector Load Word into Two Half Words and Splat [Indexed]
evstdd[x]        Vector Store Double of Double [Indexed]
evstdw[x]        Vector Store Double of Two Words [Indexed]
evstdh[x]        Vector Store Double of Four Half Words [Indexed]
evstwhe[x]       Vector Store Word of Two Half Words from Even [Indexed]
evstwho[x]       Vector Store Word of Two Half Words from Odd [Indexed]
evstwwe[x]       Vector Store Word of Word from Even [Indexed]
evstwwo[x]       Vector Store Word of Word from Odd [Indexed]

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-09-14 08:51:48 -05:00
Paul Mackerras
c6d4267ece [POWERPC] Handle alignment faults on new FP load/store instructions
This adds code to handle alignment traps generated by the following
new floating-point load/store instructions, by emulating the
instruction in the kernel (as is done for other instructions that
generate alignment traps):

lfiwax	load floating-point as integer word algebraic indexed
stfiwx	store floating-point as integer word indexed
lfdp	load floating-point double pair
lfdpx	load floating-point double pair indexed
stfdp	store floating-point double pair
stfdpx	store floating-point double pair indexed

All these except stfiwx are new in POWER6.

lfdp/lfdpx/stfdp/stfdpx load and store 16 bytes of memory into an
even/odd FP register pair.  In little-endian mode each 8-byte value is
byte-reversed separately (i.e. not as a 16-byte unit).  lfiwax/stfiwx
load or store the lower 4 bytes of a floating-point register from/to
memory; lfiwax sets the upper 4 bytes of the FP register to the sign
extension of the value loaded.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-08-17 11:01:55 +10:00
Benjamin Herrenschmidt
e4ee3891db [POWERPC] Alignment exception uses __get/put_user_inatomic
Make the alignment exception handler use the new _inatomic variants
of __get/put_user. This fixes erroneous warnings in the very rare
cases where we manage to have copy_tofrom_user_inatomic() trigger
an alignment exception.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

 arch/powerpc/kernel/align.c |   56 ++++++++++++++++++++++++--------------------
 1 file changed, 31 insertions(+), 25 deletions(-)
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-04-13 04:09:38 +10:00
Paul Mackerras
fab5db97e4 [PATCH] powerpc: Implement support for setting little-endian mode via prctl
This adds the PowerPC part of the code to allow processes to change
their endian mode via prctl.

This also extends the alignment exception handler to be able to fix up
alignment exceptions that occur in little-endian mode, both for
"PowerPC" little-endian and true little-endian.

We always enter signal handlers in big-endian mode -- the support for
little-endian mode does not amount to the creation of a little-endian
user/kernel ABI.  If the signal handler returns, the endian mode is
restored to what it was when the signal was delivered.

We have two new kernel CPU feature bits, one for PPC little-endian and
one for true little-endian.  Most of the classic 32-bit processors
support PPC little-endian, and this is reflected in the CPU feature
table.  There are two corresponding feature bits reported to userland
in the AT_HWCAP aux vector entry.

This is based on an earlier patch by Anton Blanchard.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-09 21:24:15 +10:00
Benjamin Herrenschmidt
5daf9071b5 [PATCH] powerpc: merge align.c
This patch merges align.c, the result isn't quite what was in ppc64 nor
what was in ppc32 :) It should implement all the functionalities of both
though. Kumar, since you played with that in the past, I suppose you
have some test cases for verifying that it works properly before I dig
out the 601 machine ? :)

Since it's likely that I won't be able to test all scenario, code
inspection is much welcome.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-11-18 14:39:23 +11:00