[OpenBIOS] [PATCHv2 00/11] SPARC64 context improvements

[Mark Cave-Ayland]

This patchset improves the context handling in 2 ways: firstly it unifies
the context structures between switch_to() and CIF entry, and secondly fixes
up the context switch code enough so that we can switch and return from an
arbitrary PC address in testing.

This is a precursor to fixing up the load/init-program logic so that clients
are able to access and alter their own context from Forth.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland at ilande.co.uk>

v2:
- Make sure trap level is preserved after SAVE_CPU_TRAP_STATE
- Add separate RESET_CPU_WINDOW_STATE macro
- Ensure that __context points to the saved entry state during CIF calls

Mark Cave-Ayland (11):
  SPARC64: add parameter to indicate %cwp save/restore direction
  SPARC64: allocate space in context to save global registers
  SPARC64: save/restore global registers to context when entering CIF
  SPARC64: save CIF entry globals under the client stack
  SPARC64: introduce %pc into context and use it when exiting CIF
  SPARC64: make sure that %tl is restored after SAVE_CPU_TRAP_STATE
  SPARC64: save/restore entire CPU state when entering/leaving CIF
  SPARC64: split off CPU window reset logic into RESET_CPU_WINDOW_STATE
    macro
  SPARC64: split off general CPU registers into *_GENERAL_STATE macros
  SPARC64: point __context to saved context during CIF calls
  SPARC64: switch entry.S over to use existing context macros

 arch/sparc64/call-client.S |   94 ++++++++++++++++++++++----------
 arch/sparc64/context.c     |    6 +--
 arch/sparc64/context.h     |    7 +--
 arch/sparc64/cpustate.h    |  115 ++++++++++++++++++++++++---------------
 arch/sparc64/entry.S       |   17 +++++-
 arch/sparc64/switch.S      |  129 ++++++++++++++++----------------------------
 arch/sparc64/vectors.S     |    8 ++-
 7 files changed, 213 insertions(+), 163 deletions(-)

-- 
1.7.10.4