[PATCH 00/10] xtensa: support call0 ABI kernel

[Max Filippov]

Hello,

this series adds support for building kernel with call0 ABI. This
extends linux support to xtensa cores without windowed registers option.
call0 ABI kernel still supports windowed ABI userspace on cores with
windowed registers. In this case kernel entry from the userspace saves
active register windows as usual.

Max Filippov (10):
  xtensa: move _SimulateUserKernelVectorException out of WindowVectors
  xtensa: use a14 instead of a15 in inline assembly
  xtensa: don't use a12 in strncpy_user
  xtensa: don't use a12 in __xtensa_copy_user in call0 ABI
  xtensa: definitions for call0 ABI
  xtensa: implement call0 ABI support in assembly
  xtensa: use register window specific opcodes only when present
  xtensa: only build windowed register support code when needed
  xtensa: remove unused variable wmask
  xtensa: move section symbols to asm/sections.h

 arch/xtensa/boot/boot-elf/bootstrap.S     |   2 +
 arch/xtensa/boot/boot-redboot/bootstrap.S |  72 ++++----
 arch/xtensa/include/asm/asmmacro.h        |  65 +++++++
 arch/xtensa/include/asm/atomic.h          |  26 +--
 arch/xtensa/include/asm/cmpxchg.h         |  16 +-
 arch/xtensa/include/asm/core.h            |  11 ++
 arch/xtensa/include/asm/processor.h       |  32 +++-
 arch/xtensa/include/asm/sections.h        |  41 ++++
 arch/xtensa/include/asm/traps.h           |   2 +
 arch/xtensa/kernel/align.S                |   2 +
 arch/xtensa/kernel/entry.S                | 216 ++++++++++++++--------
 arch/xtensa/kernel/head.S                 |  24 ++-
 arch/xtensa/kernel/mcount.S               |  38 +++-
 arch/xtensa/kernel/process.c              |  27 ++-
 arch/xtensa/kernel/setup.c                | 102 ++++------
 arch/xtensa/kernel/signal.c               |  12 +-
 arch/xtensa/kernel/traps.c                |   6 +-
 arch/xtensa/kernel/vectors.S              |  55 +++---
 arch/xtensa/kernel/vmlinux.lds.S          |  12 +-
 arch/xtensa/lib/strncpy_user.S            |  17 +-
 arch/xtensa/lib/usercopy.S                |  28 ++-
 21 files changed, 541 insertions(+), 265 deletions(-)
 create mode 100644 arch/xtensa/include/asm/sections.h

-- 
2.20.1