linux-toradex.git/arch/mips/mm, branch v4.3.1

MIPS: dma-default: Fix 32-bit fall back to GFP_DMA

2015-09-30T14:27:39+00:00

If there is a DMA zone (usually 24bit = 16MB I believe), but no DMA32
zone, as is the case for some 32-bit kernels, then massage_gfp_flags()
will cause DMA memory allocated for devices with a 32..63-bit
coherent_dma_mask to fall back to using __GFP_DMA, even though there may
only be 32-bits of physical address available anyway.

Correct that case to compare against a mask the size of phys_addr_t
instead of always using a 64-bit mask.

Signed-off-by: James Hogan 
Fixes: a2e715a86c6d ("MIPS: DMA: Fix computation of DMA flags from device's coherent_dma_mask.")
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Cc:  # 2.6.36+
Patchwork: https://patchwork.linux-mips.org/patch/9610/
Signed-off-by: Ralf Baechle

MIPS: Initialise MAARs on secondary CPUs

2015-09-27T12:15:26+00:00

MAARs should be initialised on each CPU (or rather, core) in the system
in order to achieve consistent behaviour & performance. Previously they
have only been initialised on the boot CPU which leads to performance
problems if tasks are later scheduled on a secondary CPU, particularly
if those tasks make use of unaligned vector accesses where some CPUs
don't handle any cases in hardware for non-speculative memory regions.
Fix this by recording the MAAR configuration from the boot CPU and
applying it to secondary CPUs as part of their bringup.

Reported-by: Doug Gilmore 
Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Cc: Rusty Russell 
Cc: Steven J. Hill 
Cc: Andrew Bresticker 
Cc: Bjorn Helgaas 
Cc: David Hildenbrand 
Cc: linux-kernel@vger.kernel.org
Cc: Aaro Koskinen 
Cc: James Hogan 
Cc: Ingo Molnar 
Cc: Markos Chandras 
Cc: Hemmo Nieminen 
Cc: Alex Smith 
Cc: Peter Zijlstra (Intel) 
Patchwork: https://patchwork.linux-mips.org/patch/11239/
Signed-off-by: Ralf Baechle

MIPS: print MAAR configuration during boot

2015-09-27T12:14:47+00:00

Verifying that the MAAR configuration is as expected is useful when
debugging the performance of a system. Print out the memory regions
configured via MAAR along with their attributes.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill 
Cc: David Hildenbrand 
Cc: linux-kernel@vger.kernel.org
Cc: Peter Zijlstra (Intel) 
Patchwork: https://patchwork.linux-mips.org/patch/11238/
Signed-off-by: Ralf Baechle

MIPS: mm: compile maar_init unconditionally

2015-09-27T12:14:00+00:00

maar_init was previously only compiled when CONFIG_NEED_MULTIPLE_NODES
was not set, which has been fine since it is only called from the
standard implementation of mem_init which has the same condition. In
preparation for calling it from the SMP startup code on secondary CPUs,
move maar_init outside of the #ifndef such that it is always compiled.

Signed-off-by: Paul Burton 
Cc: Markos Chandras 
Cc: linux-mips@linux-mips.org
Cc: Steven J. Hill 
Cc: David Hildenbrand 
Cc: linux-kernel@vger.kernel.org
Cc: Ingo Molnar 
Patchwork: https://patchwork.linux-mips.org/patch/11237/
Signed-off-by: Ralf Baechle

dma-mapping: consolidate dma_{alloc,free}_noncoherent

2015-09-10T20:29:01+00:00

Most architectures do not support non-coherent allocations and either
define dma_{alloc,free}_noncoherent to their coherent versions or stub
them out.

Openrisc uses dma_{alloc,free}_attrs to implement them, and only Mips
implements them directly.

This patch moves the Openrisc version to common code, and handles the
DMA_ATTR_NON_CONSISTENT case in the mips dma_map_ops instance.

Note that actual non-coherent allocations require a dma_cache_sync
implementation, so if non-coherent allocations didn't work on
an architecture before this patch they still won't work after it.

[jcmvbkbc@gmail.com: fix xtensa]
Signed-off-by: Christoph Hellwig 
Cc: Arnd Bergmann 
Cc: Russell King 
Cc: Catalin Marinas 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Cc: Michal Simek 
Cc: Jonas Bonn 
Cc: Chris Metcalf 
Cc: Guan Xuetao 
Cc: Ralf Baechle 
Cc: Benjamin Herrenschmidt 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Cc: Andy Shevchenko 
Signed-off-by: Max Filippov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent}

2015-09-10T20:29:01+00:00

Since 2009 we have a nice asm-generic header implementing lots of DMA API
functions for architectures using struct dma_map_ops, but unfortunately
it's still missing a lot of APIs that all architectures still have to
duplicate.

This series consolidates the remaining functions, although we still need
arch opt outs for two of them as a few architectures have very
non-standard implementations.

This patch (of 5):

The coherent DMA allocator works the same over all architectures supporting
dma_map operations.

This patch consolidates them and converges the minor differences:

 - the debug_dma helpers are now called from all architectures, including
   those that were previously missing them
 - dma_alloc_from_coherent and dma_release_from_coherent are now always
   called from the generic alloc/free routines instead of the ops
   dma-mapping-common.h always includes dma-coherent.h to get the defintions
   for them, or the stubs if the architecture doesn't support this feature
 - checks for ->alloc / ->free presence are removed.  There is only one
   magic instead of dma_map_ops without them (mic_dma_ops) and that one
   is x86 only anyway.

Besides that only x86 needs special treatment to replace a default devices
if none is passed and tweak the gfp_flags.  An optional arch hook is provided
for that.

[linux@roeck-us.net: fix build]
[jcmvbkbc@gmail.com: fix xtensa]
Signed-off-by: Christoph Hellwig 
Cc: Arnd Bergmann 
Cc: Russell King 
Cc: Catalin Marinas 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Cc: Michal Simek 
Cc: Jonas Bonn 
Cc: Chris Metcalf 
Cc: Guan Xuetao 
Cc: Ralf Baechle 
Cc: Benjamin Herrenschmidt 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: "H. Peter Anvin" 
Cc: Andy Shevchenko 
Signed-off-by: Guenter Roeck 
Signed-off-by: Max Filippov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

MIPS: Set trap_no field in thread_struct on exception.

2015-09-03T10:08:04+00:00

This reverts commit 7281cd22973008a782860e48ed8d85d00204168c and adds
actual functionality to use the field.

MIPS: Add implementation of dma_map_ops.mmap()

2015-09-03T10:08:01+00:00

The generic implementation of dma_map_ops.mmap(), dma_common_mmap(),
is not correct for non-coherent devices. It expects to be passed a
virtual address previously returned by dma_alloc_coherent(), which for
a non-coherent device will return a KSEG1 address. It then attempts to
convert that virtual address to a physical address using virt_to_page()
which will yield an incorrect address.

Also, dma_common_mmap() does not handle the DMA_ATTR_WRITE_COMBINE
attribute, and therefore dma_mmap_writecombine() will not actually set
the appropriate pgprot_t flags for write combining.

This patch adds an implementation of dma_map_ops.mmap() that correctly
handles KSEG1 addresses, and enables write combining when requested.

Signed-off-by: Alex Smith 
Cc: Sadegh Abbasi 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10808/
Signed-off-by: Ralf Baechle

MIPS: Refactor dumping of TLB registers for r3k/r4k

2015-09-03T10:07:45+00:00

The TLB registers are dumped in a couble of places:
 - sysrq_tlbdump_single() - when dumping TLB state.
 - do_mcheck() - in response to a machine check error.

The main TLB registers also differ between r3k and r4k, but r4k appears
to be assumed.

Refactor this code into a dump_tlb_regs() function, implemented for both
r3k and r4k, and used by both of the above functions.

Fixes: d1e9a4f54735 ("MIPS: Add SysRq operation to dump TLBs on all CPUs")
Suggested-by: Maciej W. Rozycki 
Signed-off-by: James Hogan 
Cc: Maciej W. Rozycki 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10721/
Signed-off-by: Ralf Baechle

MIPS: mm: default platform_maar_init using bootmem data

2015-09-03T10:07:40+00:00

Introduce a default weak implementation of platform_maar_init which
makes use of the data that platforms already provide to the bootmem
allocator. This should hopefully cover the most common configurations,
reduce the duplication of information provided by platforms & leaves
platforms with the option of providing a custom implementation if
required.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Cc: Paolo Bonzini 
Cc: Steven J. Hill 
Cc: linux-kernel@vger.kernel.org
Cc: Ard Biesheuvel 
Patchwork: https://patchwork.linux-mips.org/patch/10676/
Signed-off-by: Ralf Baechle