linux.git/arch/powerpc/Kconfig.debug, branch v3.10

powerpc: Add an in memory udbg console

2013-05-07T20:36:49+00:00

This patch adds a new udbg early debug console which utilises
statically defined input and output buffers stored within the kernel
BSS. It is primarily designed to assist with bring up of new hardware
which may not have a working console but which has a method of
reading/writing kernel memory.

This version incorporates comments made by Ben H (thanks!).

Changes from v1:
	- Add memory barriers.
	- Ensure updating of read/write positions is atomic.

Signed-off-by: Alistair Popple 
Signed-off-by: Benjamin Herrenschmidt

powerpc: IOMMU fault injection

2012-07-10T09:18:59+00:00

Add the ability to inject IOMMU faults. We enable this per device
via a fail_iommu sysfs property, similar to fault injection on other
subsystems.

An example:

...
0003:01:00.1 Ethernet controller: Emulex Corporation OneConnect 10Gb NIC (be3) (rev 02)

To inject one error to this device:

echo 1 > /sys/bus/pci/devices/0003:01:00.1/fail_iommu
echo 1 > /sys/kernel/debug/fail_iommu/probability
echo 1 > /sys/kernel/debug/fail_iommu/times

As feared, the first failure injected on the be3 results in an
unrecoverable error, taking down both functions of the card
permanently:

be2net 0003:01:00.1: Unrecoverable error in the card

Signed-off-by: Anton Blanchard 
Signed-off-by: Benjamin Herrenschmidt

irqdomain: Remove powerpc dependency from debugfs file

2012-03-29T20:31:02+00:00

The debugfs code is really generic for all platforms.  This patch removes the
powerpc-specific directory reference and makes it available to all
architectures.

Signed-off-by: Grant Likely

powerpc: remove CONFIG_PPC_ISERIES from the architecture Kconfig files

2012-02-27T00:33:58+00:00

After this, we can remove the legacy iSeries code more easily.

Signed-off-by: Stephen Rothwell 
Signed-off-by: Benjamin Herrenschmidt

powerpc: Implement CONFIG_STRICT_DEVMEM

2011-11-28T00:42:08+00:00

As described in the help text in the patch, this token restricts general
access to /dev/mem as a way of increasing the security. Specifically, access
to exclusive IOMEM and kernel RAM is denied unless CONFIG_STRICT_DEVMEM is
set to 'n'.

Implement the 'devmem_is_allowed()' interface for Powerpc. It will be
called from range_is_allowed() when userpsace attempts to access /dev/mem.

This patch is based on an earlier patch from Steve Best and with input from
Paul Mackerras and Scott Wood.

[BenH] Fixed a typo or two and removed the generic change which should
       be submitted as a separate patch

Signed-off-by: Sukadev Bhattiprolu 
Signed-off-by: Benjamin Herrenschmidt

powerpc/powernv: Support for OPAL console

2011-09-20T06:09:54+00:00

This adds a udbg and an hvc console backend for supporting a console
using the OPAL console interfaces.

On OPAL v1 we have hvc0 mapped to whatever console the system was
configured for (network or hvsi serial port) via the service
processor.

On OPAL v2 we have hvcN mapped to the Nth console provided by OPAL
which generally corresponds to:

	hvc0 : network console (raw protocol)
	hvc1 : serial port S1 (hvsi)
	hvc2 : serial port S2 (hvsi)

Note: At this point, early debug console only works with OPAL v1
and shouldn't be enabled in a normal kernel.

Signed-off-by: Benjamin Herrenschmidt

powerpc/udbg: Fix Kconfig entry for avoiding 44x early debug with KVM

2011-09-20T05:53:24+00:00

It was preventing the global early debug selection whenever KVM was enabled
instead of only preventing the 440 specific one.

Signed-off-by: Benjamin Herrenschmidt

powerpc/ps3: Add gelic udbg driver

2011-09-19T23:20:05+00:00

Add a new udbg driver for the PS3 gelic Ehthernet device.

This driver shares only a few stucture and constant definitions with the
gelic Ethernet device driver, so is implemented as a stand-alone driver
with no dependencies on the gelic Ethernet device driver.

Signed-off-by: Hector Martin 
Signed-off-by: Andre Heider 
Signed-off-by: Geoff Levand 
Signed-off-by: Benjamin Herrenschmidt

powerpc/pseries: Re-implement HVSI as part of hvc_vio

2011-06-29T07:48:35+00:00

On pseries machines, consoles are provided by the hypervisor using
a low level get_chars/put_chars type interface. However, this is
really just a transport to the service processor which implements
them either as "raw" console (networked consoles, HMC, ...) or as
"hvsi" serial ports.

The later is a simple packet protocol on top of the raw character
interface that is supposed to convey additional "serial port" style
semantics. In practice however, all it does is provide a way to
read the CD line and set/clear our DTR line, that's it.

We currently implement the "raw" protocol as an hvc console backend
(/dev/hvcN) and the "hvsi" protocol using a separate tty driver
(/dev/hvsi0).

However this is quite impractical. The arbitrary difference between
the two type of devices has been a major source of user (and distro)
confusion. Additionally, there's an additional mini -hvsi implementation
in the pseries platform code for our low level debug console and early
boot kernel messages, which means code duplication, though that low
level variant is impractical as it's incapable of doing the initial
protocol negociation to establish the link to the FSP.

This essentially replaces the dedicated hvsi driver and the platform
udbg code completely by extending the existing hvc_vio backend used
in "raw" mode so that:

 - It now supports HVSI as well
 - We add support for hvc backend providing tiocm{get,set}
 - It also provides a udbg interface for early debug and boot console

This is overall less code, though this will only be obvious once we
remove the old "hvsi" driver, which is still available for now. When
the old driver is enabled, the new code still kicks in for the low
level udbg console, replacing the old mini implementation in the platform
code, it just doesn't provide the higher level "hvc" interface.

In addition to producing generally simler code, this has several benefits
over our current situation:

 - The user/distro only has to deal with /dev/hvcN for the hypervisor
console, avoiding all sort of confusion that has plagued us in the past

 - The tty, kernel and low level debug console all use the same code
base which supports the full protocol establishment process, thus the
console is now available much earlier than it used to be with the
old HVSI driver. The kernel console works much earlier and udbg is
available much earlier too. Hackers can enable a hard coded very-early
debug console as well that works with HVSI (previously that was only
supported for the "raw" mode).

I've tried to keep the same semantics as hvsi relative to how I react
to things like CD changes, with some subtle differences though:

 - I clear DTR on close if HUPCL is set

 - Current hvsi triggers a hangup if it detects a up->down transition
   on CD (you can still open a console with CD down). My new implementation
   triggers a hangup if the link to the FSP is severed, and severs it upon
   detecting a up->down transition on CD.

Signed-off-by: Benjamin Herrenschmidt

lib: consolidate DEBUG_STACK_USAGE option

2011-05-25T15:39:54+00:00

Most arches define CONFIG_DEBUG_STACK_USAGE exactly the same way.  Move it
to lib/Kconfig.debug so each arch doesn't have to define it.  This
obviously makes the option generic, but that's fine because the config is
already used in generic code.

It's not obvious to me that sysrq-P actually does anything caution by
keeping the most inclusive wording.

Signed-off-by: Stephen Boyd 
Cc: Chris Metcalf 
Acked-by: David S. Miller 
Acked-by: Richard Weinberger 
Acked-by: Mike Frysinger 
Cc: Russell King 
Cc: Hirokazu Takata 
Acked-by: Ralf Baechle 
Cc: Paul Mackerras 
Acked-by: Benjamin Herrenschmidt 
Cc: Chen Liqin 
Cc: Lennox Wu 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds