linux-toradex.git/arch/mips/include/asm/processor.h, branch v4.4.93

MIPS: Fix 64k page support for 32 bit kernels.

2016-06-24T17:18:22+00:00

commit d7de413475f443957a0c1d256e405d19b3a2cb22 upstream.

TASK_SIZE was defined as 0x7fff8000UL which for 64k pages is not a
multiple of the page size.  Somewhere further down the math fails
such that executing an ELF binary fails.

Signed-off-by: Ralf Baechle 
Tested-by: Joshua Henderson 
Cc: James Hogan 
Signed-off-by: Greg Kroah-Hartman

MIPS: Initial implementation of a VDSO

2015-11-11T07:36:36+00:00

Add an initial implementation of a proper (i.e. an ELF shared library)
VDSO. With this commit it does not export any symbols, it only replaces
the current signal return trampoline page. A later commit will add user
implementations of gettimeofday()/clock_gettime().

To support both new toolchains and old ones which don't generate ABI
flags section, we define its content manually and then use a tool
(genvdso) to patch up the section to have the correct name and type.
genvdso also extracts symbol offsets ({,rt_}sigreturn) needed by the
kernel, and generates a C file containing a "struct mips_vdso_image"
containing both the VDSO data and these offsets. This C file is
compiled into the kernel.

On 64-bit kernels we require a different VDSO for each supported ABI,
so we may build up to 3 different VDSOs. The VDSO to use is selected by
the mips_abi structure.

A kernel/user shared data page is created and mapped below the VDSO
image. This is currently empty, but will be used by the user time
function implementations which are added later.

[markos.chandras@imgtec.com:
- Add more comments
- Move abi detection in genvdso.h since it's the get_symbol function
that needs it.
- Add an R6 specific way to calculate the base address of VDSO in order
to avoid the branch instruction which affects performance.
- Do not patch .gnu.attributes since it's not needed for dynamic linking.
- Simplify Makefile a little bit.
- checkpatch fixes
- Restrict VDSO support for binutils < 2.25 for pre-R6
- Include atomic64.h for O32 variant on MIPS64]

Signed-off-by: Alex Smith 
Signed-off-by: Markos Chandras 
Cc: Matthew Fortune 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11337/
Signed-off-by: Ralf Baechle

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: MSA: Fix big-endian FPR_IDX implementation

2015-03-27T18:42:48+00:00

The maximum word size is 64-bits since MSA state is saved using st.d
which stores two 64-bit words, therefore reimplement FPR_IDX using xor,
and only within each 64-bit word.

Signed-off-by: James Hogan 
Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9169/
Signed-off-by: Ralf Baechle

MIPS: OCTEON: Save and restore CP2 SHA3 state

2015-02-20T14:29:08+00:00

Allocate new save space, and then save/restore the registers if
OCTEON III.

Signed-off-by: David Daney 
Signed-off-by: Aleksey Makarov 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8935/
Signed-off-by: Ralf Baechle

MIPS: Remove unneeded #ifdef KERNEL from asm/processor.h

2015-02-20T13:14:52+00:00

Signed-off-by: David Daney 
Signed-off-by: Aleksey Makarov 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8737/
Signed-off-by: Ralf Baechle

MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS

2015-02-12T11:30:29+00:00

Userland code may be built using an ABI which permits linking to objects
that have more restrictive floating point requirements. For example,
userland code may be built to target the O32 FPXX ABI. Such code may be
linked with other FPXX code, or code built for either one of the more
restrictive FP32 or FP64. When linking with more restrictive code, the
overall requirement of the process becomes that of the more restrictive
code. The kernel has no way to know in advance which mode the process
will need to be executed in, and indeed it may need to change during
execution. The dynamic loader is the only code which will know the
overall required mode, and so it needs to have a means to instruct the
kernel to switch the FP mode of the process.

This patch introduces 2 new options to the prctl syscall which provide
such a capability. The FP mode of the process is represented as a
simple bitmask combining a number of mode bits mirroring those present
in the hardware. Userland can either retrieve the current FP mode of
the process:

  mode = prctl(PR_GET_FP_MODE);

or modify the current FP mode of the process:

  err = prctl(PR_SET_FP_MODE, new_mode);

Signed-off-by: Paul Burton 
Cc: Matthew Fortune 
Cc: Markos Chandras 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8899/
Signed-off-by: Ralf Baechle

sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW

2014-09-24T12:47:05+00:00

Kirill found that there's a subtle race in the
__ARCH_WANT_UNLOCKED_CTXSW code, and instead of fixing it, remove the
entire exception because neither arch that uses it seems to actually
still require it.

Boot tested on mips64el (qemu) only.

Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Kirill Tkhai 
Cc: Andrew Morton 
Cc: Davidlohr Bueso 
Cc: Fenghua Yu 
Cc: James Hogan 
Cc: Kees Cook 
Cc: Linus Torvalds 
Cc: Paul Burton 
Cc: Qais Yousef 
Cc: Ralf Baechle 
Cc: Tony Luck 
Cc: oleg@redhat.com
Cc: linux@roeck-us.net
Cc: linux-ia64@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Link: http://lkml.kernel.org/r/20140923150641.GH3312@worktop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar

Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus

2014-08-07T15:47:00+00:00

Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for 3.17.  It contains:

   - misc Cavium Octeon, BCM47xx, BCM63xx and Alchemy  updates
   - MIPS ptrace updates and cleanups
   - various fixes that will also go to -stable
   - a number of cleanups and small non-critical fixes.
   - NUMA support for the Loongson 3.
   - more support for MSA
   - support for MAAR
   - various FP enhancements and fixes"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (139 commits)
  MIPS: jz4740: remove unnecessary null test before debugfs_remove
  MIPS: Octeon: remove unnecessary null test before debugfs_remove_recursive
  MIPS: ZBOOT: implement stack protector in compressed boot phase
  MIPS: mipsreg: remove duplicate MIPS_CONF4_FTLBSETS_SHIFT
  MIPS: Bonito64: remove a duplicate define
  MIPS: Malta: initialise MAARs
  MIPS: Initialise MAARs
  MIPS: detect presence of MAARs
  MIPS: define MAAR register accessors & bits
  MIPS: mark MSA experimental
  MIPS: Don't build MSA support unless it can be used
  MIPS: consistently clear MSA flags when starting & copying threads
  MIPS: 16 byte align MSA vector context
  MIPS: disable preemption whilst initialising MSA
  MIPS: ensure MSA gets disabled during boot
  MIPS: fix read_msa_* & write_msa_* functions on non-MSA toolchains
  MIPS: fix MSA context for tasks which don't use FP first
  MIPS: init upper 64b of vector registers when MSA is first used
  MIPS: save/disable MSA in lose_fpu
  MIPS: preserve scalar FP CSR when switching vector context
  ...

MIPS: 16 byte align MSA vector context

2014-08-01T22:06:44+00:00

The MSA specification upon first read appears to suggest that it is safe
to perform vector loads & stores with arbitrary alignment. However it
leaves provision for "address-dependent exceptions"... Align the vector
context to a 16 byte boundary to ensure that the kernel cannot cause any
such exceptions.

Note that the fpu field of struct thread_struct was already at a 16 byte
boundary within the struct, the introduction of FPU_ALIGN simply makes
the requirement explicit. The only part of this impacting the generated
kernel binary is ARCH_MIN_TASKALIGN.

Signed-off-by: Paul Burton 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7308/
Signed-off-by: Ralf Baechle