litmus-rt.git/arch/mips/mm, branch linux-tip

MIPS: Honor L2 bypass bit

2010-10-29T18:08:52+00:00

On many of the newer MIPS32 cores, CP0 CONFIG2 bit 12 (L2B) indicates
that the L2 cache is disabled and therefore Linux should not attempt
to use it.

[Ralf: Moved the code added by Kevin's original patch into a separate
function that can easily be replaced for platforms that need more a
different probe.]

Signed-off-by: Kevin Cernekee 
Cc: linux-mips@linux-mips.org>
Cc: 
Patchwork: https://patchwork.linux-mips.org/patch/1723/
Signed-off-by: Ralf Baechle

MIPS: Decouple BMIPS CPU support from bcm47xx/bcm63xx SoC code

2010-10-29T18:08:50+00:00

BMIPS processor cores are used in 50+ different chipsets spread across
5+ product lines.  In many cases the chipsets do not share the same
peripheral register layouts, the same register blocks, the same
interrupt controllers, the same memory maps, or much of anything else.

But, across radically different SoCs that share nothing more than the
same BMIPS CPU, a few things are still mostly constant:

SMP operations
Access to performance counters
DMA cache coherency quirks
Cache and memory bus configuration

So, it makes sense to treat each BMIPS processor type as a generic
"building block," rather than tying it to a specific SoC.  This makes it
easier to support a large number of BMIPS-based chipsets without
unnecessary duplication of code, and provides the infrastructure needed
to support BMIPS-proprietary features.

Signed-off-by: Kevin Cernekee 
Cc: mbizon@freebox.fr
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Tested-by: Florian Fainelli 
Patchwork: https://patchwork.linux-mips.org/patch/1706/
Signed-off-by: Ralf Baechle

MIPS: add support for software performance events

2010-10-29T18:08:48+00:00

Software events are required as part of the measurable stuff by the
Linux performance counter subsystem. Here is the list of events added by
this patch:
PERF_COUNT_SW_PAGE_FAULTS
PERF_COUNT_SW_PAGE_FAULTS_MIN
PERF_COUNT_SW_PAGE_FAULTS_MAJ
PERF_COUNT_SW_ALIGNMENT_FAULTS
PERF_COUNT_SW_EMULATION_FAULTS

Signed-off-by: Deng-Cheng Zhu 
To: linux-mips@linux-mips.org
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: mingo@elte.hu
Cc: acme@redhat.com
Cc: jamie.iles@picochip.com
Acked-by: David Daney 
Reviewed-by: Matt Fleming 
Patchwork: https://patchwork.linux-mips.org/patch/1686/
Signed-off-by: Ralf Baechle

MIPS: Octeon: Apply CN63XXP1 errata workarounds.

2010-10-29T18:08:43+00:00

The CN63XXP1 needs a couple of workarounds to ensure memory is not written
in unexpected ways.

All PREF with hints in the range 0-4,6-24 are replaced with PREF 28.  We
pass a flag to the assembler to cover compiler generated code, and patch
uasm for the dynamically generated code.

The write buffer threshold is reduced to 4.

Signed-off-by: David Daney 
Patchwork: http://patchwork.linux-mips.org/patch/1672/
Signed-off-by: Ralf Baechle

MIPS: Octeon: Handle Octeon II caches.

2010-10-29T18:08:36+00:00

Signed-off-by: David Daney 
Patchwork: http://patchwork.linux-mips.org/patch/1664/
Signed-off-by: Ralf Baechle

MIPS: Convert DMA to use dma-mapping-common.h

2010-10-29T18:08:31+00:00

Use asm-generic/dma-mapping-common.h to handle all DMA mapping operations
and establish a default get_dma_ops() that forwards all operations to the
existing code.

Augment dev_archdata to carry a pointer to the struct dma_map_ops, allowing
DMA operations to be overridden on a per device basis.  Currently this is
never filled in, so the default dma_map_ops are used.  A follow-on patch
sets this for Octeon PCI devices.

Also initialize the dma_debug system as it is now used if it is configured.

Includes fixes by Kevin Cernekee .

Signed-off-by: David Daney 
Patchwork: http://patchwork.linux-mips.org/patch/1637/
Patchwork: http://patchwork.linux-mips.org/patch/1678/
Signed-off-by: Ralf Baechle

MIPS: Remove wait argument of r4k_on_each_cpu

2010-10-29T18:08:25+00:00

All callers were passing in 1 anyway.

Signed-off-by: Ralf Baechle

MIPS: More detailed description of r4k_on_each_cpu

2010-10-29T18:08:25+00:00

Signed-off-by: Ralf Baechle

mm: fix race in kunmap_atomic()

2010-10-28T01:03:05+00:00

Christoph reported a nice splat which illustrated a race in the new stack
based kmap_atomic implementation.

The problem is that we pop our stack slot before we're completely done
resetting its state -- in particular clearing the PTE (sometimes that's
CONFIG_DEBUG_HIGHMEM).  If an interrupt happens before we actually clear
the PTE used for the last slot, that interrupt can reuse the slot in a
dirty state, which triggers a BUG in kmap_atomic().

Fix this by introducing kmap_atomic_idx() which reports the current slot
index without actually releasing it and use that to find the PTE and delay
the _pop() until after we're completely done.

Signed-off-by: Peter Zijlstra 
Reported-by: Christoph Hellwig 
Acked-by: Rik van Riel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: stack based kmap_atomic()

2010-10-26T23:52:08+00:00

Keep the current interface but ignore the KM_type and use a stack based
approach.

The advantage is that we get rid of crappy code like:

	#define __KM_PTE			\
		(in_nmi() ? KM_NMI_PTE : 	\
		 in_irq() ? KM_IRQ_PTE :	\
		 KM_PTE0)

and in general can stop worrying about what context we're in and what kmap
slots might be appropriate for that.

The downside is that FRV kmap_atomic() gets more expensive.

For now we use a CPP trick suggested by Andrew:

  #define kmap_atomic(page, args...) __kmap_atomic(page)

to avoid having to touch all kmap_atomic() users in a single patch.

[ not compiled on:
  - mn10300: the arch doesn't actually build with highmem to begin with ]

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix up drivers/gpu/drm/i915/intel_overlay.c]
Acked-by: Rik van Riel 
Signed-off-by: Peter Zijlstra 
Acked-by: Chris Metcalf 
Cc: David Howells 
Cc: Hugh Dickins 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Cc: Steven Rostedt 
Cc: Russell King 
Cc: Ralf Baechle 
Cc: David Miller 
Cc: Paul Mackerras 
Cc: Benjamin Herrenschmidt 
Cc: Dave Airlie 
Cc: Li Zefan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds