This patch adds support for the SH4 to convert a subnormal double
into a float by catching the FPE and implementing the FCNVDS
instruction in software.
Signed-off-by: NCarl Shaw <carl.shaw@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This follows the sparc changes a439fe51.

Most of the moving about was done with Sam's directions at:

http://marc.info/?l=linux-sh&m=121724823706062&w=2

with subsequent hacking and fixups entirely my fault.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Presently with preempt enabled there's the possibility to be preempted
after the TIF_USEDFPU test and the register save, leading to bogus
state post-__switch_to(). Use an explicit preempt_disable()/enable()
pair around unlazy_fpu()/clear_fpu() to avoid this. Follows the x86
change.
Reported-by: NTakuo Koguchi <takuo.koguchi.sw@hitachi.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Signed-off-by: NKieran Bingham <kbingham@mpc-data.co.uk>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Spelling fixes in arch/sh/.
Signed-off-by: NSimon Arlott <simon@fire.lp0.eu>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

There are a few different cases for figuring out how to
size the instruction. We read in the instruction located
at regs->pc - 4 when rewinding the opcode to figure out if
there's a 32-bit opcode before the faulting instruction, with
a default of a - 2 adjustment on a mismatch. In practice this
works for the cases where pc - 4 is just another 16-bit opcode,
or we happen to have a 32-bit and a 16-bit immediately
preceeding the pc value.

In the cases where we aren't rewinding, this is much less ugly..

We also don't bother fixing up the places where we're explicitly
dealing with 16-bit instructions, since this might lead to
confusion regarding the encoding size possibilities on other
CPU variants.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Remove the previous saving of fault codes into the thread_struct
as they are never used, and appeared to be inherited from x86.
Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This fixes up the kernel for gcc4. The existing exception handlers
needed some wrapping for pt_regs access, acessing the registers
via a RELOC_HIDE() pointer.

The strcpy() issues popped up here too, so add -ffreestanding and
kill off the symbol export.
Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!