litmus-rt.git/arch/powerpc/kernel/Makefile, branch test

powerpc: kill PPC_OF

2015-03-17T09:04:32+00:00

We have set CONFIG_PPC_OF to always 'y' in commit 0a498d96a332
("powerpc: set CONFIG_PPC_OF=y always for ARCH=powerpc") nine years
ago. And the arch/ppc also has gone away for many years. The OF
functionality was also moved to a common place and be used by many
archs. So it does make no sense to keep such a option in the current
kernel. Just kill it.

Signed-off-by: Kevin Hao 
Acked-by: Benjamin Herrenschmidt 
Signed-off-by: Michael Ellerman

powerpc: Separate ppc32 symbol exports into ppc_ksyms_32.c

2014-09-25T13:14:40+00:00

Simplify things considerably by moving all the ppc32 specific
symbol exports into its own file.

Signed-off-by: Anton Blanchard 
Signed-off-by: Michael Ellerman

powerpc: Remove platforms/wsp and associated pieces

2014-06-11T06:35:38+00:00

__attribute__ ((unused))

WSP is the last user of CONFIG_PPC_A2, so we remove that as well.

Although CONFIG_PPC_ICSWX still exists, it's no longer selectable for
any Book3E platform, so we can remove the code in mmu-book3e.h that
depended on it.

Signed-off-by: Michael Ellerman 
Signed-off-by: Benjamin Herrenschmidt

powerpc: use libfdt accessors for header data

2014-04-30T05:59:18+00:00

With libfdt support, we can take advantage of helper accessors in libfdt
for accessing the FDT header data. This makes the code more readable and
makes the FDT blob structure more opaque to the kernel. This also
prepares for removing struct boot_param_header completely.

Signed-off-by: Rob Herring 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Tested-by: Grant Likely 
Tested-by: Stephen Chivers

clk: mpc5xxx: switch to COMMON_CLK, retire PPC_CLOCK

2014-01-12T17:53:04+00:00

the setup before the change was
- arch/powerpc/Kconfig had the PPC_CLOCK option, off by default
- depending on the PPC_CLOCK option the arch/powerpc/kernel/clock.c file
  was built, which implements the clk.h API but always returns -ENOSYS
  unless a platform registers specific callbacks
- the MPC52xx platform selected PPC_CLOCK but did not register any
  callbacks, thus all clk.h API calls keep resulting in -ENOSYS errors
  (which is OK, all peripheral drivers deal with the situation)
- the MPC512x platform selected PPC_CLOCK and registered specific
  callbacks implemented in arch/powerpc/platforms/512x/clock.c, thus
  provided real support for the clock API
- no other powerpc platform did select PPC_CLOCK

the situation after the change is
- the MPC512x platform implements the COMMON_CLK interface, and thus the
  PPC_CLOCK approach in arch/powerpc/platforms/512x/clock.c has become
  obsolete
- the MPC52xx platform still lacks genuine support for the clk.h API
  while this is not a change against the previous situation (the error
  code returned from COMMON_CLK stubs differs but every call still
  results in an error)
- with all references gone, the arch/powerpc/kernel/clock.c wrapper and
  the PPC_CLOCK option have become obsolete, as did the clk_interface.h
  header file

the switch from PPC_CLOCK to COMMON_CLK is done for all platforms within
the same commit such that multiplatform kernels (the combination of 512x
and 52xx within one executable) keep working

Cc: Mike Turquette 
Cc: Anatolij Gustschin 
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Gerhard Sittig 
Signed-off-by: Anatolij Gustschin

powerpc/book3s: Decode and save machine check event.

2013-12-05T05:05:20+00:00

Now that we handle machine check in linux, the MCE decoding should also
take place in linux host. This info is crucial to log before we go down
in case we can not handle the machine check errors. This patch decodes
and populates a machine check event which contain high level meaning full
MCE information.

We do this in real mode C code with ME bit on. The MCE information is still
available on emergency stack (in pt_regs structure format). Even if we take
another exception at this point the MCE early handler will allocate a new
stack frame on top of current one. So when we return back here we still have
our MCE information safe on current stack.

We use per cpu buffer to save high level MCE information. Each per cpu buffer
is an array of machine check event structure indexed by per cpu counter
mce_nest_count. The mce_nest_count is incremented every time we enter
machine check early handler in real mode to get the current free slot
(index = mce_nest_count - 1). The mce_nest_count is decremented once the
MCE info is consumed by virtual mode machine exception handler.

This patch provides save_mce_event(), get_mce_event() and release_mce_event()
generic routines that can be used by machine check handlers to populate and
retrieve the event. The routine release_mce_event() will free the event slot so
that it can be reused. Caller can invoke get_mce_event() with a release flag
either to release the event slot immediately OR keep it so that it can be
fetched again. The event slot can be also released anytime by invoking
release_mce_event().

This patch also updates kvm code to invoke get_mce_event to retrieve generic
mce event rather than paca->opal_mce_evt.

The KVM code always calls get_mce_event() with release flags set to false so
that event is available for linus host machine

If machine check occurs while we are in guest, KVM tries to handle the error.
If KVM is able to handle MC error successfully, it enters the guest and
delivers the machine check to guest. If KVM is not able to handle MC error, it
exists the guest and passes the control to linux host machine check handler
which then logs MC event and decides how to handle it in linux host. In failure
case, KVM needs to make sure that the MC event is available for linux host to
consume. Hence KVM always calls get_mce_event() with release flags set to false
and later it invokes release_mce_event() only if it succeeds to handle error.

Signed-off-by: Mahesh Salgaonkar 
Signed-off-by: Benjamin Herrenschmidt

powerpc/book3s: Flush SLB/TLBs if we get SLB/TLB machine check errors on power7.

2013-12-05T05:04:39+00:00

If we get a machine check exception due to SLB or TLB errors, then flush
SLBs/TLBs and reload SLBs to recover. We do this in real mode before turning
on MMU. Otherwise we would run into nested machine checks.

If we get a machine check when we are in guest, then just flush the
SLBs and continue. This patch handles errors for power7. The next
patch will handle errors for power8

Signed-off-by: Mahesh Salgaonkar 
Signed-off-by: Paul Mackerras 
Signed-off-by: Benjamin Herrenschmidt

powerpc/pseries: Move lparcfg.c to platforms/pseries

2013-08-28T01:20:54+00:00

This file is entirely pseries specific nowadays, so move it out
of arch/powerpc/kernel where it doesn't belong anymore.

Signed-off-by: Benjamin Herrenschmidt

powerpc/8xx: Remove last traces of 8XX_MINIMAL_FPEMU

2013-08-14T04:58:53+00:00

The Kconfig symbol 8XX_MINIMAL_FPEMU was removed in commit 968219fa33
("powerpc/8xx: Remove 8xx specific "minimal FPU emulation""). But that
commit didn't remove all code depending on that symbol. Do so now.

Signed-off-by: Paul Bolle 
Signed-off-by: Benjamin Herrenschmidt

powerpc: Better split CONFIG_PPC_INDIRECT_PIO and CONFIG_PPC_INDIRECT_MMIO

2013-08-14T04:57:50+00:00

Remove the generic PPC_INDIRECT_IO and ensure we only add overhead
to the right accessors. IE. If only CONFIG_PPC_INDIRECT_PIO is set,
we don't add overhead to all MMIO accessors.

Signed-off-by: Benjamin Herrenschmidt