Warning log:
CHECK   arch/microblaze/mm/fault.c
arch/microblaze/mm/fault.c:51:6: warning: incorrect type in initializer (different address spaces)
arch/microblaze/mm/fault.c:51:6:    expected unknown type 2const [noderef] *__gu_addr<asn:1>
arch/microblaze/mm/fault.c:51:6:    got unsigned int *<noident>
arch/microblaze/mm/fault.c:68:6: warning: symbol 'bad_page_fault' was not declared. Should it be static?
Signed-off-by: NMichal Simek <monstr@monstr.eu>

Function sw_exception is linked with asm code.

Warning log:
CHECK   arch/microblaze/kernel/exceptions.c
arch/microblaze/kernel/exceptions.c:53:6: warning: symbol 'sw_exception' was not declared. Should it be static?
Signed-off-by: NMichal Simek <monstr@monstr.eu>

Kgdb uses brki r16, 0x18 instruction to call
low level _debug_exception function which save
current state to pt_regs and call microblaze_kgdb_break
function. _debug_exception should be called only from
the kernel space. User space calling is not supported
because user application debugging uses different handling.

pt_regs_to_gdb_regs loads additional special registers
which can't be changed

 * Enable KGDB in Kconfig
 * Remove ancient not-tested KGDB support
 * Remove ancient _debug_exception code from entry.S

Only MMU KGDB support is supported.
Signed-off-by: NMichal Simek <monstr@monstr.eu>
CC: Jason Wessel <jason.wessel@windriver.com>
CC: John Williams <john.williams@petalogix.com>
CC: Edgar E. Iglesias <edgar.iglesias@petalogix.com>
CC: linux-kernel@vger.kernel.org
Acked-by: NJason Wessel <jason.wessel@windriver.com>

Implement intelligent backtracing by searching for stack frame creation,
and emitting only return addresses. Use print_hex_dump() to display the
entire binary kernel stack.

Limitation: MMU kernels are not currently able to trace beyond a system trap
(interrupt, syscall, etc.). It is the intent of this patch to provide
infrastructure that can be extended to add this capability later.

Changes from V1:
* Removed checks in find_frame_creation() that prevented location of the frame
  creation instruction in heavily optimized code
* Various formatting/commenting/file location tweaks per review comments
* Dropped Kconfig option to enable STACKTRACE as something logically separate
Signed-off-by: NSteven J. Magnani <steve@digidescorp.com>

I found several function which we don't use that's why I am removing them.
Signed-off-by: NMichal Simek <monstr@monstr.eu>

Signed-off-by: NMichal Simek <monstr@monstr.eu>

This change remove sparse errors.
Signed-off-by: NMichal Simek <monstr@monstr.eu>

Reviewed-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NStephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: NJohn Linn <john.linn@xilinx.com>
Acked-by: NJohn Williams <john.williams@petalogix.com>
Signed-off-by: NMichal Simek <monstr@monstr.eu>