linux-toradex.git/arch/powerpc/math-emu, branch v3.0.44

powerpc/85xx: Fix SPE float to integer conversion failure

2011-03-15T18:48:15+00:00

Conversion from float to integer should based on both the instruction
encoding and the sign of the operand.

A simple testcase to show the issue:

static float fm;
static signed int si_min = (-2147483647 - 1);
static unsigned int ui;
int main()
{
       fm = (float) si_min; ;
       ui = (unsigned int)fm;
       printf("ui=%d, should be %d\n", ui, si_min);

       return 0;
}
Result: ui=-1, should be -2147483648

Signed-off-by: Shan Hai 
Signed-off-by: Kumar Gala

powerpc/85xx: Workaroudn e500 CPU erratum A005

2011-03-15T15:05:06+00:00

This erratum can occur if a single-precision floating-point,
double-precision floating-point or vector floating-point instruction on a
mispredicted branch path signals one of the floating-point data interrupts
which are enabled by the SPEFSCR (FINVE, FDBZE, FUNFE or FOVFE bits).  This
interrupt must be recorded in a one-cycle window when the misprediction is
resolved.  If this extremely rare event should occur, the result could be:

The SPE Data Exception from the mispredicted path may be reported
erroneously if a single-precision floating-point, double-precision
floating-point or vector floating-point instruction is the second
instruction on the correct branch path.

According to errata description, some efp instructions which are not
supposed to trigger SPE exceptions can trigger the exceptions in this case.
However, as we haven't emulated these instructions here, a signal will
send to userspace, and userspace application would exit.

This patch re-issue the efp instruction that we haven't emulated,
so that hardware can properly execute it again if this case happen.

Signed-off-by: Liu Yu 
Signed-off-by: Kumar Gala

powerpc/Makefiles: Change to new flag variables

2010-10-13T05:19:22+00:00

Replace EXTRA_CFLAGS with ccflags-y and EXTRA_AFLAGS with asflags-y.

Signed-off-by: matt mooney 
Signed-off-by: Benjamin Herrenschmidt

powerpc/math-emu: Fix efp dependence

2009-03-11T11:00:08+00:00

There is no dependece between efp and math-emu.  But when disable math-emu
the efp code cannot be built.

Signed-off-by: Liu Yu 
Signed-off-by: Kumar Gala

powerpc: Add SPE/EFP math emulation for E500v1/v2 processors.

2008-12-03T14:19:16+00:00

This patch add the handlers of SPE/EFP exceptions.
The code is used to emulate float point arithmetic,
when MSR(SPE) is enabled and receive EFP data interrupt or EFP round interrupt.

This patch has no conflict with or dependence on FP math-emu.

The code has been tested by TestFloat.

Now the code doesn't support SPE/EFP instructions emulation
(it won't be called when receive program interrupt),
but it could be easily added.

Signed-off-by: Liu Yu 
Signed-off-by: Kumar Gala

powerpc/math-emu: Remove redundant 'ret'

2008-12-03T14:19:15+00:00

FP_DECL_EX is already used, so ret is redundant.
And FP_SET_EXCEPTION will add status into return value.

Signed-off-by: Liu Yu 
Signed-off-by: Kumar Gala

powerpc/math-emu: Use kernel generic math-emu code

2008-10-01T13:40:07+00:00

The math emulation code is centered around a set of generic macros that
provide the core of the emulation that are shared by the various
architectures and other projects (like glibc).  Each arch implements its
own sfp-machine.h to specific various arch specific details.

For historic reasons that are now lost the powerpc math-emu code had
its own version of the common headers.  This moves us to using the
kernel generic version and thus getting fixes when those are updated.

Also cleaned up exception/error reporting from the FP emulation functions.

Signed-off-by: Kumar Gala

powerpc: Add macros to access floating point registers in thread_struct.

2008-07-01T01:28:43+00:00

We are going to change where the floating point registers are stored
in the thread_struct, so in preparation add some macros to access the
floating point registers.  Update all code to use these new macros.

Signed-off-by: Michael Neuling 
Signed-off-by: Paul Mackerras

[POWERPC] Replace remaining FUNCTION occurrences

2008-04-01T09:43:09+00:00

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison 
Cc: Benjamin Herrenschmidt 
Signed-off-by: Andrew Morton 
Signed-off-by: Paul Mackerras

[POWERPC] Fix carry bug in 128-bit unsigned integer adding

2008-01-24T01:34:21+00:00

Synchronize it to the definition in include/math-emu/op-4.h for short term.

Signed-off-by: Liu Yu 
Signed-off-by: Kumar Gala