linux-toradex.git/arch/arc/kernel/ptrace.c, branch v4.2.7

ARCv2: Support for ARCv2 ISA and HS38x cores

2015-06-22T08:36:55+00:00

The notable features are:
    - SMP configurations of upto 4 cores with coherency
    - Optional L2 Cache and IO-Coherency
    - Revised Interrupt Architecture (multiple priorites, reg banks,
        auto stack switch, auto regfile save/restore)
    - MMUv4 (PIPT dcache, Huge Pages)
    - Instructions for
	* 64bit load/store: LDD, STD
	* Hardware assisted divide/remainder: DIV, REM
	* Function prologue/epilogue: ENTER_S, LEAVE_S
	* IRQ enable/disable: CLRI, SETI
	* pop count: FFS, FLS
	* SETcc, BMSKN, XBFU...

Signed-off-by: Vineet Gupta

ARC: Make way for pt_regs != user_regs_struct

2015-06-19T12:39:40+00:00

These have been register compatible so far. However ARCv2 mandates
different pt_regs layout (due to h/w auto save). To keep pt_regs same
for both, we start by removing the assumption - used mainly for block
copies between the 2 structs in signal handling and ptrace

Signed-off-by: Vineet Gupta

ARC: Implement ptrace(PTRACE_GET_THREAD_AREA)

2014-06-26T04:44:08+00:00

This patch adds implementation of GET_THREAD_AREA ptrace request type. This
is required by GDB to debug NPTL applications.

Signed-off-by: Anton Kolesov 
Signed-off-by: Vineet Gupta

ARC: Ignore ptrace SETREGSET request for synthetic register "stop_pc"

2013-10-12T06:30:36+00:00

ARCompact TRAP_S insn used for breakpoints, commits before exception is
taken (updating architectural PC). So ptregs->ret contains next-PC and
not the breakpoint PC itself. This is different from other restartable
exceptions such as TLB Miss where ptregs->ret has exact faulting PC.
gdb needs to know exact-PC hence ARC ptrace GETREGSET provides for
@stop_pc which returns ptregs->ret vs. EFA depending on the
situation.

However, writing stop_pc (SETREGSET request), which updates ptregs->ret
doesn't makes sense stop_pc doesn't always correspond to that reg as
described above.

This was not an issue so far since user_regs->ret / user_regs->stop_pc
had same value and both writing to ptregs->ret was OK, needless, but NOT
broken, hence not observed.

With gdb "jump", they diverge, and user_regs->ret updating ptregs is
overwritten immediately with stop_pc, which this patch fixes.

Reported-by: Anton Kolesov 
Signed-off-by: Vineet Gupta

ARC: pt_regs update #3: Remove unused gutter at start of callee_regs

2013-06-22T13:53:22+00:00

This is trickier than prev two:

* context switching code saves kernel mode callee regs in the format of
  struct callee_regs thus needs adjustment. This also reduces the height
  of topmost kernel stack frame by 1 word.

* Since kernel stack unwinder is sensitive to height of topmost kernel
  stack frame, that needs a word of adjustment too.

ptrace needs a bit of updating since pt_regs now diverges from
user_regs_struct.

Signed-off-by: Vineet Gupta

ARC: pt_regs update #2: Remove unused gutter at start of pt_regs

2013-06-22T13:53:22+00:00

Signed-off-by: Vineet Gupta

ARC: ptrace support

2013-02-15T17:45:59+00:00

Signed-off-by: Vineet Gupta 
Acked-by: Arnd Bergmann

ARC: Last bits (stubs) to get to a running kernel with UART

2013-02-15T17:45:57+00:00

This was part of port buildup strategy from Arnd to have a minimal kernel
at first and then add optional features (stacktracing, ptrace, smp,
kprobes, oprofile....)

Signed-off-by: Vineet Gupta