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authorJames Morris <jmorris@macbook.(none)>2009-12-03 12:03:40 +0530
committerJames Morris <jmorris@macbook.(none)>2009-12-03 12:03:40 +0530
commitc84d6efd363a3948eb32ec40d46bab6338580454 (patch)
tree3ba7ac46e6626fe8ac843834588609eb6ccee5c6 /arch/mips/math-emu
parent7539cf4b92be4aecc573ea962135f246a7a33401 (diff)
parent22763c5cf3690a681551162c15d34d935308c8d7 (diff)
Merge branch 'master' into next
Diffstat (limited to 'arch/mips/math-emu')
-rw-r--r--arch/mips/math-emu/cp1emu.c41
-rw-r--r--arch/mips/math-emu/dp_simple.c13
-rw-r--r--arch/mips/math-emu/sp_simple.c11
3 files changed, 28 insertions, 37 deletions
diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c
index 890f77927d6..454b5392449 100644
--- a/arch/mips/math-emu/cp1emu.c
+++ b/arch/mips/math-emu/cp1emu.c
@@ -163,33 +163,34 @@ static int isBranchInstr(mips_instruction * i)
/*
* In the Linux kernel, we support selection of FPR format on the
- * basis of the Status.FR bit. This does imply that, if a full 32
- * FPRs are desired, there needs to be a flip-flop that can be written
- * to one at that bit position. In any case, O32 MIPS ABI uses
- * only the even FPRs (Status.FR = 0).
+ * basis of the Status.FR bit. If an FPU is not present, the FR bit
+ * is hardwired to zero, which would imply a 32-bit FPU even for
+ * 64-bit CPUs. For 64-bit kernels with no FPU we use TIF_32BIT_REGS
+ * as a proxy for the FR bit so that a 64-bit FPU is emulated. In any
+ * case, for a 32-bit kernel which uses the O32 MIPS ABI, only the
+ * even FPRs are used (Status.FR = 0).
*/
-
-#define CP0_STATUS_FR_SUPPORT
-
-#ifdef CP0_STATUS_FR_SUPPORT
-#define FR_BIT ST0_FR
+static inline int cop1_64bit(struct pt_regs *xcp)
+{
+ if (cpu_has_fpu)
+ return xcp->cp0_status & ST0_FR;
+#ifdef CONFIG_64BIT
+ return !test_thread_flag(TIF_32BIT_REGS);
#else
-#define FR_BIT 0
+ return 0;
#endif
+}
+
+#define SIFROMREG(si, x) ((si) = cop1_64bit(xcp) || !(x & 1) ? \
+ (int)ctx->fpr[x] : (int)(ctx->fpr[x & ~1] >> 32))
-#define SIFROMREG(si, x) ((si) = \
- (xcp->cp0_status & FR_BIT) || !(x & 1) ? \
- (int)ctx->fpr[x] : \
- (int)(ctx->fpr[x & ~1] >> 32 ))
-#define SITOREG(si, x) (ctx->fpr[x & ~((xcp->cp0_status & FR_BIT) == 0)] = \
- (xcp->cp0_status & FR_BIT) || !(x & 1) ? \
+#define SITOREG(si, x) (ctx->fpr[x & ~(cop1_64bit(xcp) == 0)] = \
+ cop1_64bit(xcp) || !(x & 1) ? \
ctx->fpr[x & ~1] >> 32 << 32 | (u32)(si) : \
ctx->fpr[x & ~1] << 32 >> 32 | (u64)(si) << 32)
-#define DIFROMREG(di, x) ((di) = \
- ctx->fpr[x & ~((xcp->cp0_status & FR_BIT) == 0)])
-#define DITOREG(di, x) (ctx->fpr[x & ~((xcp->cp0_status & FR_BIT) == 0)] \
- = (di))
+#define DIFROMREG(di, x) ((di) = ctx->fpr[x & ~(cop1_64bit(xcp) == 0)])
+#define DITOREG(di, x) (ctx->fpr[x & ~(cop1_64bit(xcp) == 0)] = (di))
#define SPFROMREG(sp, x) SIFROMREG((sp).bits, x)
#define SPTOREG(sp, x) SITOREG((sp).bits, x)
diff --git a/arch/mips/math-emu/dp_simple.c b/arch/mips/math-emu/dp_simple.c
index 1c555e6c6a9..d9ae1dbabda 100644
--- a/arch/mips/math-emu/dp_simple.c
+++ b/arch/mips/math-emu/dp_simple.c
@@ -62,8 +62,6 @@ ieee754dp ieee754dp_neg(ieee754dp x)
return ieee754dp_nanxcpt(y, "neg");
}
- if (ieee754dp_isnan(x)) /* but not infinity */
- return ieee754dp_nanxcpt(x, "neg", x);
return x;
}
@@ -76,15 +74,12 @@ ieee754dp ieee754dp_abs(ieee754dp x)
CLEARCX;
FLUSHXDP;
+ /* Clear sign ALWAYS, irrespective of NaN */
+ DPSIGN(x) = 0;
+
if (xc == IEEE754_CLASS_SNAN) {
- SETCX(IEEE754_INVALID_OPERATION);
- return ieee754dp_nanxcpt(ieee754dp_indef(), "neg");
+ return ieee754dp_nanxcpt(ieee754dp_indef(), "abs");
}
- if (ieee754dp_isnan(x)) /* but not infinity */
- return ieee754dp_nanxcpt(x, "abs", x);
-
- /* quick fix up */
- DPSIGN(x) = 0;
return x;
}
diff --git a/arch/mips/math-emu/sp_simple.c b/arch/mips/math-emu/sp_simple.c
index 770f0f4677c..3175477d36f 100644
--- a/arch/mips/math-emu/sp_simple.c
+++ b/arch/mips/math-emu/sp_simple.c
@@ -62,8 +62,6 @@ ieee754sp ieee754sp_neg(ieee754sp x)
return ieee754sp_nanxcpt(y, "neg");
}
- if (ieee754sp_isnan(x)) /* but not infinity */
- return ieee754sp_nanxcpt(x, "neg", x);
return x;
}
@@ -76,15 +74,12 @@ ieee754sp ieee754sp_abs(ieee754sp x)
CLEARCX;
FLUSHXSP;
+ /* Clear sign ALWAYS, irrespective of NaN */
+ SPSIGN(x) = 0;
+
if (xc == IEEE754_CLASS_SNAN) {
- SETCX(IEEE754_INVALID_OPERATION);
return ieee754sp_nanxcpt(ieee754sp_indef(), "abs");
}
- if (ieee754sp_isnan(x)) /* but not infinity */
- return ieee754sp_nanxcpt(x, "abs", x);
-
- /* quick fix up */
- SPSIGN(x) = 0;
return x;
}