Commit Graph

65065 Commits (a546498f3bf9aac311c66f965186373aee2ca0b0)

Author SHA1 Message Date
Benjamin Herrenschmidt a546498f3b powerpc: Call do_page_fault() with interrupts off
We currently turn interrupts back to their previous state before
calling do_page_fault(). This can be annoying when debugging as
a bad fault will potentially have lost some processor state before
getting into the debugger.

We also end up calling some generic code with interrupts enabled
such as notify_page_fault() with interrupts enabled, which could
be unexpected.

This changes our code to behave more like other architectures,
and make the assembly entry code call into do_page_faults() with
interrupts disabled. They are conditionally re-enabled from
within do_page_fault() in the same spot x86 does it.

While there, add the might_sleep() test in the case of a successful
trylock of the mmap semaphore, again like x86.

Also fix a bug in the existing assembly where r12 (_MSR) could get
clobbered by C calls (the DTL accounting in the exception common
macro and DISABLE_INTS) in some cases.

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

v2. Add the r12 clobber fix
2012-03-09 10:55:08 +11:00
Benjamin Herrenschmidt 1b70117924 powerpc: Improve behaviour of irq tracing on 64-bit exception entry
Some exceptions would unconditionally disable interrupts on entry,
which is fine, but calling lockdep every time not only adds more
overhead than strictly needed, but also means we get quite a few
"redudant" disable logged, which makes it hard to spot the really
bad ones.

So instead, split the macro used by the exception code into a
normal one and a separate one used when CONFIG_TRACE_IRQFLAGS is
enabled, and make the later skip th tracing if interrupts were
already disabled.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-09 10:55:06 +11:00
Benjamin Herrenschmidt 1421ae0b29 powerpc: Improve 64-bit syscall entry/exit
We unconditionally hard enable interrupts. This is unnecessary as
syscalls are expected to always be called with interrupts enabled.

While at it, we add a WARN_ON if that is not the case and
CONFIG_TRACE_IRQFLAGS is enabled (we don't want to add overhead
to the fast path when this is not set though).

Thus let's remove the enabling (and associated irq tracing) from
the syscall entry path. Also on Book3S, replace a few mfmsr
instructions with loads of PACAMSR from the PACA, which should be
faster & schedule better.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-09 10:55:04 +11:00
Benjamin Herrenschmidt fe1952fc0a powerpc: Rework runlatch code
This moves the inlines into system.h and changes the runlatch
code to use the thread local flags (non-atomic) rather than
the TIF flags (atomic) to keep track of the latch state.

The code to turn it back on in an asynchronous interrupt is
now simplified and partially inlined.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-09 10:55:02 +11:00
Benjamin Herrenschmidt 7450f6f03e powerpc: Use the same interrupt prolog for perfmon as other interrupts
The perfmon interrupt is the sole user of a special variant of the
interrupt prolog which differs from the one used by external and timer
interrupts in that it saves the non-volatile GPRs and doesn't turn the
runlatch on.

The former is unnecessary and the later is arguably incorrect, so
let's clean that up by using the same prolog. While at it we rename
that prolog to use the _ASYNC prefix.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-09 10:55:00 +11:00
Benjamin Herrenschmidt 4f8cf36f48 powerpc: Remove legacy iSeries bits from assembly files
This removes the various bits of assembly in the kernel entry,
exception handling and SLB management code that were specific
to running under the legacy iSeries hypervisor which is no
longer supported.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-09 10:54:59 +11:00
Stephen Rothwell b078766026 powerpc: clean up vio.c
This cleans up vio.c after the removal of the legacy iSeries platform.
It also removes some no longer referenced include files.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-09 10:35:23 +11:00
Stephen Rothwell 8ee3e0d696 powerpc: Remove the main legacy iSerie platform code
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-09 10:35:11 +11:00
Akinobu Mita 2d4b971287 powerpc/pmac: Use string library in nvram code
- Use memchr_inv to check if the data contains all 0xFF bytes.
  It is faster than looping for each byte.

- Use memcmp to compare memory areas

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-07 17:09:05 +11:00
Grant Likely ad5b7f1350 powerpc: Make SPARSE_IRQ required
All IRQs on powerpc are managed via irq_domain anyway, there isn't really
any advantage to turning SPARSE_IRQ off, and it's the direction we want
to take the kernel design anyway.  This patch makes powerpc always use
SPARSE_IRQ.

On pseries_defconfig, SPARSE_IRQ adds only about 0x300 bytes to the
.text sections, and removes about 0x20000 from the data section for the
static irq_desc table.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Ben Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-07 17:09:04 +11:00
Nishanth Aravamudan e9daf2ad7f powerpc/prom: Remove limit on maximum size of properties
On a 16TB system (using AMS/CMO), I get:

WARNING: ignoring large property [/ibm,dynamic-reconfiguration-memory] ibm,dynamic-memory length 0x000000000017ffec

and significantly less memory is thus shown to the partition. As far as
I can tell, the constant used is arbitrary. Ben Herrenschmidt provided
additional background that

> The limit was originally set because of Apple machines carrying ROM
> images in the device-tree, at a time where we were much more memory
> constrained than we are now.

and that it is likely not very useful any longer.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-07 17:06:10 +11:00
Matt Fleming a2007ce844 powerpc: Use set_current_blocked() and block_sigmask()
As described in e6fa16ab ("signal: sigprocmask() should do
retarget_shared_pending()") the modification of current->blocked is
incorrect as we need to check whether the signal we're about to block
is pending in the shared queue.

Also, use the new helper function introduced in commit 5e6292c0f2
("signal: add block_sigmask() for adding sigmask to current->blocked")
which centralises the code for updating current->blocked after
successfully delivering a signal and reduces the amount of duplicate
code across architectures. In the past some architectures got this
code wrong, so using this helper function should stop that from
happening again.

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-07 17:06:09 +11:00
Joe Perches a2234b4bae powerpc: Use vsprintf extention %pf with builtin_return_address
Emit the function name not the address when possible.

builtin_return_address() gives an address.  When building
a kernel with CONFIG_KALLSYMS, emit the actual function
name not the address.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-07 17:06:09 +11:00
Jimi Xenidis de801de139 powerpc/icswx: Fix race condition with IPI setting ACOP
There is a race where a thread causes a coprocessor type to be valid
in its own ACOP _and_ in the current context, but it does not
propagate to the ACOP register of other threads in time for them to
use it.  The original code tries to solve this by sending an IPI to
all threads on the system, which is heavy handed, but unfortunately
still provides a window where the icswx is issued by other threads and
the ACOP is not up to date.

This patch detects that the ACOP DSI fault was a "false positive" and
syncs the ACOP and causes the icswx to be replayed.

Signed-off-by: Jimi Xenidis <jimix@pobox.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-07 17:06:09 +11:00
Anton Blanchard a6cf7ed511 powerpc/atomic: Implement atomic*_inc_not_zero
Implement atomic_inc_not_zero and atomic64_inc_not_zero. At the
moment we use atomic*_add_unless which requires us to put 0 and
1 constants into registers. We can also avoid a subtract by
saving the original value in a second temporary.

This removes 3 instructions from fget:

- c0000000001b63c0:       39 00 00 00     li      r8,0
- c0000000001b63c4:       39 40 00 01     li      r10,1
...
- c0000000001b63e8:       7c 0a 00 50     subf    r0,r10,r0

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-07 17:06:08 +11:00
Danny Kukawka 0a167e0a5c arch/powerpc/platforms/powernv/setup.c: included asm/xics.h twice
arch/powerpc/platforms/powernv/setup.c: included 'asm/xics.h' twice,
remove the duplicate.

Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-27 11:33:59 +11:00
Danny Kukawka ed7e3d1ca7 arch/powerpc/kvm/book3s_hv.c: included linux/sched.h twice
arch/powerpc/kvm/book3s_hv.c: included 'linux/sched.h' twice,
remove the duplicate.

Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-27 11:33:58 +11:00
Stephen Rothwell 3d066d77cf powerpc: remove CONFIG_PPC_ISERIES from the architecture Kconfig files
After this, we can remove the legacy iSeries code more easily.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-27 11:33:58 +11:00
Benjamin Herrenschmidt fe83364f0b powerpc/mpic: Fix allocation of reverse-map for multi-ISU mpics
When using a multi-ISU MPIC, we can interrupts up to
isu_size * MPIC_MAX_ISU, not just isu_size, so allocate
the right size reverse map.

Without this, the code will constantly fallback to
a linear search.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-27 11:33:58 +11:00
Benjamin Herrenschmidt f851013cb2 Merge remote-tracking branch 'origin/master' into next 2012-02-27 10:50:11 +11:00
Linus Torvalds ee3253241a This is the arch/c6x part of commit 7c43185138
which was dropped because c6x had not yet been merged at the time.
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Merge tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming

This is the arch/c6x part of commit 7c43185138 ("Kbuild: Use dtc's -d
(dependency) option") which was dropped because c6x had not yet been
merged at the time.

* tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming:
  Kbuild: Use dtc's -d (dependency) option
2012-02-24 09:01:46 -08:00
Linus Torvalds 37e79cbf7d SH/R-Mobile fixes for 3.3-rc5
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Merge tag 'rmobile-for-linus' of git://github.com/pmundt/linux-sh

SH/R-Mobile fixes for 3.3-rc5

* tag 'rmobile-for-linus' of git://github.com/pmundt/linux-sh:
  arch/arm/mach-shmobile/board-ag5evm.c: included linux/dma-mapping.h twice
  ARM: mach-shmobile: r8a7779 PFC IPSR4 fix
  ARM: mach-shmobile: sh73a0 PSTR 32-bit access fix
  ARM: mach-shmobile: add GPIO-to-IRQ translation to sh7372
  ARM: mach-shmobile: clock-sh73a0: add DSIxPHY clock support
  arm: fix compile failure in mach-shmobile/board-ag5evm.c
  ARM: mach-shmobile: mackerel: add ak4642 amixer settings on comment
  ARM: mach-shmobile: mackerel: use renesas_usbhs instead of r8a66597_hcd
  ARM: mach-shmobile: simplify MMCIF DMA configuration
  ARM: mach-shmobile: IRQ driven GPIO key support for Kota2
  ARM: mach-shmobile: sh73a0 IRQ sparse alloc fix
  ARM: mach-shmobile: sh73a0 PINT IRQ base fix
2012-02-24 08:57:22 -08:00
Linus Torvalds 0e69e08401 SuperH fixes for 3.3-rc5
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Merge tag 'sh-for-linus' of git://github.com/pmundt/linux-sh

SuperH fixes for 3.3-rc5

* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
  sh: Fix sh2a build error for CONFIG_CACHE_WRITETHROUGH
  sh: modify a resource of sh_eth_giga1_resources in board-sh7757lcr
  arch/sh: remove references to cpu_*_map.
  sh: Fix typo in pci-sh7780.c
  sh: add platform_device for SPI1 in setup-sh7757
  sh: modify resource for SPI0 in setup-sh7757
  sh: se7724: fix compile breakage
  sh: clkfwk: bugfix: use clk_reparent() for div6 clocks
  sh: clock-sh7724: fixup sh_fsi clock settings
  sh: sh7757lcr: update to the new MMCIF DMA configuration
  sh: fix the sh_mmcif_plat_data in board-sh7757lcr
  video: pvr2fb: Fix up spurious section mismatch warnings.
  sh: Defer to asm-generic/device.h.
2012-02-24 08:56:51 -08:00
Danny Kukawka 7372a4cd6c arch/arm/mach-shmobile/board-ag5evm.c: included linux/dma-mapping.h twice
arch/arm/mach-shmobile/board-ag5evm.c: included 'linux/dma-mapping.h'
twice, remove the duplicate.

Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-02-24 13:32:17 +09:00
Magnus Damm 74eb436ec0 ARM: mach-shmobile: r8a7779 PFC IPSR4 fix
Fix the bit field width information for the IPSR4 register
in the r8a7779 pin function controller (PFC).

Without this fix the Marzen board fails to receive data
over the serial console due to misconfigured pin function
for the RX pin.

Signed-off-by: Magnus Damm <damm@opensource.se>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-02-24 13:24:59 +09:00
Magnus Damm 689189fb01 ARM: mach-shmobile: sh73a0 PSTR 32-bit access fix
Convert the sh73a0 SMP code to use 32-bit PSTR access.

This fixes wakeup from deep sleep for sh73a0 secondary CPUs.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-02-24 13:24:58 +09:00
Paul Mundt 35eb304b5c Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into rmobile-fixes-for-linus 2012-02-24 13:23:23 +09:00
Phil Edworthy 1ae911cba4 sh: Fix sh2a build error for CONFIG_CACHE_WRITETHROUGH
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-02-24 13:21:46 +09:00
Shimoda, Yoshihiro befe0756d5 sh: modify a resource of sh_eth_giga1_resources in board-sh7757lcr
The latest sh_eth driver needs a resource of TSU in the channel 1,
if the controller has TSU registers. So, this patch adds the resource.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-02-24 13:21:46 +09:00
Rusty Russell 004f4ce9f3 arch/sh: remove references to cpu_*_map.
This has been obsolescent for a while; time for the final push.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: linux-sh@vger.kernel.org
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-02-24 13:21:45 +09:00
Masanari Iida ecfb68c673 sh: Fix typo in pci-sh7780.c
Correct spelling "erorr" to "error" in
arch/sh/drivers/pci/pci-sh7780.c

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-02-24 13:21:44 +09:00
Linus Torvalds 73c8e679aa Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
BenH says:
 'Here are a few more powerpc bits for you.  A stupid regression I
  introduced with my previous commit to "fix" program check exceptions
  (brown paper bag for me), fix the cpuidle default, a bug fix for
  something that isn't strictly speaking a regression but some upstream
  changes causes it to show in lockdep now while it didn't before, and
  finally a trivial one for rusty to make his life easier later on
  removing the old cpumask cruft. '

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Fix various issues with return to userspace
  cpuidle: Default y on powerpc pSeries
  powerpc: Fix program check handling when lockdep is enabled
  powerpc: Remove references to cpu_*_map
2012-02-23 11:48:36 -08:00
Michael Ellerman f2699491e0 powerpc/perf: Move perf core & PMU code into a subdirectory
The perf code has grown a lot since it started, and is big enough to
warrant its own subdirectory. For reference it's ~60% bigger than the
oprofile code. It declutters the kernel directory, makes it simpler to
grep for "just perf stuff", and allows us to shorten some filenames.

While we're at it, make it more obvious that we have two implementations
of the core perf logic. One for (roughly) Book3S CPUs, which was the
original implementation, and the other for Freescale embedded CPUs.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:04 +11:00
Mahesh Salgaonkar 12d9299241 fadump: Remove the phyp assisted dump code.
Remove the phyp assisted dump implementation which is not is use.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:03 +11:00
Mahesh Salgaonkar 67b43b9d7c fadump: Invalidate the fadump registration during machine shutdown.
If dump is active during system reboot, shutdown or halt then invalidate
the fadump registration as it does not get invalidated automatically.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:03 +11:00
Mahesh Salgaonkar b500afff11 fadump: Invalidate registration and release reserved memory for general use.
This patch introduces an sysfs interface '/sys/kernel/fadump_release_mem' to
invalidate the last fadump registration, invalidate '/proc/vmcore', release
the reserved memory for general use and re-register for future kernel dump.
Once the dump is copied to the disk, unlike phyp dump, the userspace tool
can release all the memory reserved for dump with one single operation of
echo 1 to '/sys/kernel/fadump_release_mem'.

Release the reserved memory region excluding the size of the memory required
for future kernel dump registration. And therefore, unlike kdump, Fadump
doesn't need a 2nd reboot to get back the system to the production
configuration.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:02 +11:00
Mahesh Salgaonkar d34c5f26cf fadump: Add PT_NOTE program header for vmcoreinfo
Introduce a PT_NOTE program header that points to physical address of
vmcoreinfo_note buffer declared in kernel/kexec.c. The vmcoreinfo
note buffer is populated during crash_fadump() at the time of system
crash.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:02 +11:00
Mahesh Salgaonkar ebaeb5ae24 fadump: Convert firmware-assisted cpu state dump data into elf notes.
When registered for firmware assisted dump on powerpc, firmware preserves
the registers for the active CPUs during a system crash. This patch reads
the cpu register data stored in Firmware-assisted dump format (except for
crashing cpu) and converts it into elf notes and updates the PT_NOTE program
header accordingly. The exact register state for crashing cpu is saved to
fadump crash info structure in scratch area during crash_fadump() and read
during second kernel boot.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:01 +11:00
Mahesh Salgaonkar 2df173d9e8 fadump: Initialize elfcore header and add PT_LOAD program headers.
Build the crash memory range list by traversing through system memory during
the first kernel before we register for firmware-assisted dump. After the
successful dump registration, initialize the elfcore header and populate
PT_LOAD program headers with crash memory ranges. The elfcore header is
saved in the scratch area within the reserved memory. The scratch area starts
at the end of the memory reserved for saving RMR region contents. The
scratch area contains fadump crash info structure that contains magic number
for fadump validation and physical address where the eflcore header can be
found. This structure will also be used to pass some important crash info
data to the second kernel which will help second kernel to populate ELF core
header with correct data before it gets exported through /proc/vmcore. Since
the firmware preserves the entire partition memory at the time of crash the
contents of the scratch area will be preserved till second kernel boot.

Since the memory dump exported through /proc/vmcore is in ELF format similar
to kdump, it will help us to reuse the kdump infrastructure for dump capture
and filtering. Unlike phyp dump, userspace tool does not need to refer any
sysfs interface while reading /proc/vmcore.

NOTE: The current design implementation does not address a possibility of
introducing additional fields (in future) to this structure without affecting
compatibility. It's on TODO list to come up with better approach to
address this.

Reserved dump area start => +-------------------------------------+
                            |  CPU state dump data                |
                            +-------------------------------------+
                            |  HPTE region data                   |
                            +-------------------------------------+
                            |  RMR region data                    |
Scratch area start       => +-------------------------------------+
                            |  fadump crash info structure {      |
                            |     magic nummber                   |
                     +------|---- elfcorehdr_addr                 |
                     |      |  }                                  |
                     +----> +-------------------------------------+
                            |  ELF core header                    |
Reserved dump area end   => +-------------------------------------+

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:01 +11:00
Mahesh Salgaonkar 3ccc00a7e0 fadump: Register for firmware assisted dump.
On 2012-02-20 11:02:51 Mon, Paul Mackerras wrote:
> On Thu, Feb 16, 2012 at 04:44:30PM +0530, Mahesh J Salgaonkar wrote:
>
> If I have read the code correctly, we are going to get this printk on
> non-pSeries machines or on older pSeries machines, even if the user
> has not put the fadump=on option on the kernel command line.  The
> printk will be annoying since there is no actual error condition.  It
> seems to me that the condition for the printk should include
> fw_dump.fadump_enabled.  In other words you should probably add
>
> 	if (!fw_dump.fadump_enabled)
> 		return 0;
>
> at the beginning of the function.

Hi Paul,

Thanks for pointing it out. Please find the updated patch below.

The existing patches above this (4/10 through 10/10) cleanly applies
on this update.

Thanks,
-Mahesh.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:01 +11:00
Mahesh Salgaonkar eb39c8803d fadump: Reserve the memory for firmware assisted dump.
Reserve the memory during early boot to preserve CPU state data, HPTE region
and RMA (real mode area) region data in case of kernel crash. At the time of
crash, powerpc firmware will store CPU state data, HPTE region data and move
RMA region data to the reserved memory area.

If the firmware-assisted dump fails to reserve the memory, then fallback
to existing kexec-based kdump.

Most of the code implementation to reserve memory has been
adapted from phyp assisted dump implementation written by Linas Vepstas
and Manish Ahuja

This patch also introduces a config option CONFIG_FA_DUMP for firmware
assisted dump feature on Powerpc (ppc64) architecture.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:01 +11:00
Kyle Moffett e55d7f737d powerpc/mpic: Remove duplicate MPIC_WANTS_RESET flag
There are two separate flags controlling whether or not the MPIC is
reset during initialization, which is completely unnecessary, and only
one of them can be specified in the device tree.

Also, most platforms in-tree right now do actually want to reset the
MPIC during initialization anyways, which means lots of duplicate code
passing the MPIC_WANTS_RESET flag.

Fix all of the callers which currently do not pass the MPIC_WANTS_RESET
flag to pass the MPIC_NO_RESET flag, then remove the MPIC_WANTS_RESET
flag and make the code reset the MPIC by default.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:00 +11:00
Kyle Moffett c1b8d45db4 powerpc/mpic: Add "last-interrupt-source" property to override hardware
The FreeScale PowerQUICC-III-compatible (mpc85xx/mpc86xx) MPICs do not
correctly report the number of hardware interrupt sources, so software
needs to override the detected value with "256".

To avoid needing to write custom board-specific code to detect that
scenario, allow it to be easily overridden in the device-tree.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:50:00 +11:00
Kyle Moffett 5019609fce powerpc/mpic: Remove MPIC_BROKEN_FRR_NIRQS and duplicate irq_count
The mpic->irq_count variable is only used as a software error-checking
limit to determine whether or not an IRQ number is valid.  In board code
which does not manually specify an IRQ count to mpic_alloc(), i.e. 0, it
is automatically detected from the number of ISUs and the ISU size.

In practice, all hardware ends up with irq_count == num_sources, so all
of the runtime checks on mpic->irq_count should just check the value of
mpic->num_sources instead.

When platform hardware does not correctly report the number of IRQs,
which only happens on the MPC85xx/MPC86xx, the MPIC_BROKEN_FRR_NIRQS
flag is used to override the detected value of num_sources with the
manual irq_count parameter.  Since there's no need to manually specify
the number of IRQs except in this case, the extra flag can be eliminated
and the test changed to "irq_count != 0".

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:49:59 +11:00
Kyle Moffett 9ca163c860 fsl/mpic: Create and document the "single-cpu-affinity" device-tree flag
The Freescale MPIC (and perhaps others in the future) is incapable of
routing non-IPI interrupts to more than once CPU at a time.  Currently
all of the Freescale boards msut pass the MPIC_SINGLE_DEST_CPU flag to
mpic_alloc(), but that information should really be present in the
device-tree.

Older board code can't rely on the device-tree having the property set,
but newer platforms won't need it manually specified in the code.

[BenH: Remove unrelated changes, folded in a different patch]

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:49:59 +11:00
Kyle Moffett 98cca250ae fsl/mpic: Document and use the "big-endian" device-tree flag
The MPIC code checks for a "big-endian" property and sets the flag
MPIC_BIG_ENDIAN if one is present, although prior to the "mpic->flags"
fixup that would never have worked anways.

Unfortunately, even now that it works properly, the Freescale mpic
device-node (the "PowerQUICC-III"-compatible one) does not specify it,
so all of the board ports need to manually pass it to mpic_alloc().

Document the flag and add it to the pq3 device tree.  Existing code will
still need to pass the MPIC_BIG_ENDIAN flag because their dtb may not
have this property, but new platforms shouldn't need to do so.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:49:58 +11:00
Kyle Moffett 3a7a7176e8 powerpc/mpic: Fix use of "flags" variable in mpic_alloc()
The mpic_alloc() function takes a "flags" parameter and assigns it into
the mpic->flags variable fairly early on, but several later pieces of
code detect various device-tree properties and save them into the
"mpic->flags" variable (EG: "big-endian" => MPIC_BIG_ENDIAN).

Unfortunately, a number of codepaths (including several which test the
flag MPIC_BIG_ENDIAN!) test "flags" instead of "mpic->flags", and get
wrong answers as a result.

Consolidate the device-tree flag tests early in mpic_alloc() and change
all of the checks after "mpic->flags" is init'ed to use "mpic->flags".

[BenH: Fixed up use of mpic->node before it's initialized]

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@boeing.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-23 10:49:58 +11:00
Linus Torvalds 71c01b9d5b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
It contains 3 important fixes for ColdFire based machines:
 - fix processes getting stuck when running from strace
 - fix kernel vmalloced pages not being visible in all kernel contexts
 - fix shared user pages sometimes being visible in another process
   context

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: Do not set global share for non-kernel shared pages
  m68k: Add shared bit to Coldfire kernel page entries
  m68knommu: fix syscall tracing stuck process
2012-02-22 08:45:08 -08:00
Benjamin Herrenschmidt 18b246fa60 powerpc: Fix various issues with return to userspace
We have a few problems when returning to userspace. This is a
quick set of fixes for 3.3, I'll look into a more comprehensive
rework for 3.4. This fixes:

 - We kept interrupts soft-disabled when schedule'ing or calling
do_signal when returning to userspace as a result of a hardware
interrupt.

 - Rename do_signal to do_notify_resume like all other archs (and
do_signal_pending back to do_signal, which it was before Roland
changed it).

 - Add the missing call to key_replace_session_keyring() to
do_notify_resume().

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
2012-02-22 16:48:53 +11:00
Michael Ellerman 922b9f86a0 powerpc: Fix program check handling when lockdep is enabled
In commit 54321242af ("Disable interrupts early in Program Check"), we
switched from enabling to disabling interrupts in program_check_common.

Whereas ENABLE_INTS leaves r3 untouched, if lockdep is enabled DISABLE_INTS
calls into lockdep code and will clobber r3. That means we pass a bogus
struct pt_regs* into program_check_exception() and all hell breaks loose.

So load our regs pointer into r3 after we call DISABLE_INTS.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-02-22 16:48:49 +11:00