linux-stable.git/arch/mips/kernel/traps.c, branch v4.0

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

2015-02-22T03:41:38+00:00

Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for MIPS:

   - a number of fixes that didn't make the 3.19 release.

   - a number of cleanups.

   - preliminary support for Cavium's Octeon 3 SOCs which feature up to
     48 MIPS64 R3 cores with FPU and hardware virtualization.

   - support for MIPS R6 processors.

     Revision 6 of the MIPS architecture is a major revision of the MIPS
     architecture which does away with many of original sins of the
     architecture such as branch delay slots.  This and other changes in
     R6 require major changes throughout the entire MIPS core
     architecture code and make up for the lion share of this pull
     request.

   - finally some preparatory work for eXtendend Physical Address
     support, which allows support of up to 40 bit of physical address
     space on 32 bit processors"

     [ Ahh, MIPS can't leave the PAE brain damage alone.  It's like
       every CPU architect has to make that mistake, but pee in the snow
       by changing the TLA.  But whether it's called PAE, LPAE or XPA,
       it's horrid crud   - Linus ]

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (114 commits)
  MIPS: sead3: Corrected get_c0_perfcount_int
  MIPS: mm: Remove dead macro definitions
  MIPS: OCTEON: irq: add CIB and other fixes
  MIPS: OCTEON: Don't do acknowledge operations for level triggered irqs.
  MIPS: OCTEON: More OCTEONIII support
  MIPS: OCTEON: Remove setting of processor specific CVMCTL icache bits.
  MIPS: OCTEON: Core-15169 Workaround and general CVMSEG cleanup.
  MIPS: OCTEON: Update octeon-model.h code for new SoCs.
  MIPS: OCTEON: Implement DCache errata workaround for all CN6XXX
  MIPS: OCTEON: Add little-endian support to asm/octeon/octeon.h
  MIPS: OCTEON: Implement the core-16057 workaround
  MIPS: OCTEON: Delete unused COP2 saving code
  MIPS: OCTEON: Use correct instruction to read 64-bit COP0 register
  MIPS: OCTEON: Save and restore CP2 SHA3 state
  MIPS: OCTEON: Fix FP context save.
  MIPS: OCTEON: Save/Restore wider multiply registers in OCTEON III CPUs
  MIPS: boot: Provide more uImage options
  MIPS: Remove unneeded #ifdef __KERNEL__ from asm/processor.h
  MIPS: ip22-gio: Remove legacy suspend/resume support
  mips: pci: Add ifdef around pci_proc_domain
  ...

MIPS: Make use of the ERETNC instruction on MIPS R6

2015-02-17T15:37:37+00:00

The ERETNC instruction, introduced in MIPS R5, is similar to the ERET
one, except it does not clear the LLB bit in the LLADDR register.
This feature is necessary to safely emulate R2 LL/SC instructions.
However, on context switches, we need to clear the LLAddr/LLB bit
in order to make sure that an SC instruction from the new thread
will never succeed if it happens to interrupt an LL operation on the
same address from the previous thread.

Signed-off-by: Markos Chandras

MIPS: kernel: mips-r2-to-r6-emul: Add R2 emulator for MIPS R6

2015-02-17T15:37:37+00:00

MIPS R6 removed quite a few R2 instructions. However, there
is plenty of 
Signed-off-by: Markos Chandras

MIPS: kernel: traps: Add MIPS R6 related definitions

2015-02-17T15:37:27+00:00

Add MIPS R6 support to cache and ftlb exceptions, as well as
to the hwrena and ebase register configuration.

Signed-off-by: Leonid Yegoshin 
Signed-off-by: Markos Chandras

MIPS: Add cases for CPU_QEMU_GENERIC

2015-02-16T10:01:24+00:00

Add a CPU_QEMU_GENERIC case to various switch statements.

Signed-off-by: Leonid Yegoshin 
Signed-off-by: Markos Chandras

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

MIPS: traps: Fix inline asm ctc1 missing .set hardfloat

2015-01-30T22:05:04+00:00

Commit 842dfc11ea9a ("MIPS: Fix build with binutils 2.24.51+") in v3.18
enabled -msoft-float and sprinkled ".set hardfloat" where necessary to
use FP instructions. However it missed enable_restore_fp_context() which
since v3.17 does a ctc1 with inline assembly, causing the following
assembler errors on Mentor's 2014.05 toolchain:

{standard input}: Assembler messages:
{standard input}:2913: Error: opcode not supported on this processor: mips32r2 (mips32r2) `ctc1 $2,$31'
scripts/Makefile.build:257: recipe for target 'arch/mips/kernel/traps.o' failed

Fix that to use the new write_32bit_cp1_register() macro so that ".set
hardfloat" is automatically added when -msoft-float is in use.

Fixes 842dfc11ea9a ("MIPS: Fix build with binutils 2.24.51+")
Signed-off-by: James Hogan 
Cc: Ralf Baechle 
Cc: Paul Burton 
Cc: linux-mips@linux-mips.org
Cc:  # 3.18+, depends on "MIPS: mipsregs.h: Add write_32bit_cp1_register()"
Patchwork: https://patchwork.linux-mips.org/patch/9173/
Signed-off-by: Ralf Baechle

MIPS: traps: Dump the PageGrain and Wired registers on MC

2014-11-24T06:45:31+00:00

They can be useful to determine how the MMU is configured on a MC
exception.

Signed-off-by: Markos Chandras 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8401/
Signed-off-by: Ralf Baechle

MIPS: traps: Dump the HTW registers on a MC exception

2014-11-24T06:45:31+00:00

The HTW registers can be useful to debug a MC exception.

Signed-off-by: Markos Chandras 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8400/
Signed-off-by: Ralf Baechle

MIPS: traps: Replace printk with pr_err for MC exceptions

2014-11-24T06:45:30+00:00

printk should not be used without a KERN_ facility level

Signed-off-by: Markos Chandras 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8399/
Signed-off-by: Ralf Baechle