Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

1 files changed, 193 insertions, 0 deletions

diff --git a/arch/alpha/include/asm/fpu.h b/arch/alpha/include/asm/fpu.h
new file mode 100644
index 00000000000..ecb17a72acc
--- /dev/null
+++ b/arch/alpha/include/asm/fpu.h
@@ -0,0 +1,193 @@
+#ifndef __ASM_ALPHA_FPU_H
+#define __ASM_ALPHA_FPU_H
+
+/*
+ * Alpha floating-point control register defines:
+ */
+#define FPCR_DNOD	(1UL<<47)	/* denorm INV trap disable */
+#define FPCR_DNZ	(1UL<<48)	/* denorms to zero */
+#define FPCR_INVD	(1UL<<49)	/* invalid op disable (opt.) */
+#define FPCR_DZED	(1UL<<50)	/* division by zero disable (opt.) */
+#define FPCR_OVFD	(1UL<<51)	/* overflow disable (optional) */
+#define FPCR_INV	(1UL<<52)	/* invalid operation */
+#define FPCR_DZE	(1UL<<53)	/* division by zero */
+#define FPCR_OVF	(1UL<<54)	/* overflow */
+#define FPCR_UNF	(1UL<<55)	/* underflow */
+#define FPCR_INE	(1UL<<56)	/* inexact */
+#define FPCR_IOV	(1UL<<57)	/* integer overflow */
+#define FPCR_UNDZ	(1UL<<60)	/* underflow to zero (opt.) */
+#define FPCR_UNFD	(1UL<<61)	/* underflow disable (opt.) */
+#define FPCR_INED	(1UL<<62)	/* inexact disable (opt.) */
+#define FPCR_SUM	(1UL<<63)	/* summary bit */
+
+#define FPCR_DYN_SHIFT	58		/* first dynamic rounding mode bit */
+#define FPCR_DYN_CHOPPED (0x0UL << FPCR_DYN_SHIFT)	/* towards 0 */
+#define FPCR_DYN_MINUS	 (0x1UL << FPCR_DYN_SHIFT)	/* towards -INF */
+#define FPCR_DYN_NORMAL	 (0x2UL << FPCR_DYN_SHIFT)	/* towards nearest */
+#define FPCR_DYN_PLUS	 (0x3UL << FPCR_DYN_SHIFT)	/* towards +INF */
+#define FPCR_DYN_MASK	 (0x3UL << FPCR_DYN_SHIFT)
+
+#define FPCR_MASK	0xffff800000000000L
+
+/*
+ * IEEE trap enables are implemented in software.  These per-thread
+ * bits are stored in the "ieee_state" field of "struct thread_info".
+ * Thus, the bits are defined so as not to conflict with the
+ * floating-point enable bit (which is architected).  On top of that,
+ * we want to make these bits compatible with OSF/1 so
+ * ieee_set_fp_control() etc. can be implemented easily and
+ * compatibly.  The corresponding definitions are in
+ * /usr/include/machine/fpu.h under OSF/1.
+ */
+#define IEEE_TRAP_ENABLE_INV	(1UL<<1)	/* invalid op */
+#define IEEE_TRAP_ENABLE_DZE	(1UL<<2)	/* division by zero */
+#define IEEE_TRAP_ENABLE_OVF	(1UL<<3)	/* overflow */
+#define IEEE_TRAP_ENABLE_UNF	(1UL<<4)	/* underflow */
+#define IEEE_TRAP_ENABLE_INE	(1UL<<5)	/* inexact */
+#define IEEE_TRAP_ENABLE_DNO	(1UL<<6)	/* denorm */
+#define IEEE_TRAP_ENABLE_MASK	(IEEE_TRAP_ENABLE_INV | IEEE_TRAP_ENABLE_DZE |\
+				 IEEE_TRAP_ENABLE_OVF | IEEE_TRAP_ENABLE_UNF |\
+				 IEEE_TRAP_ENABLE_INE | IEEE_TRAP_ENABLE_DNO)
+
+/* Denorm and Underflow flushing */
+#define IEEE_MAP_DMZ		(1UL<<12)	/* Map denorm inputs to zero */
+#define IEEE_MAP_UMZ		(1UL<<13)	/* Map underflowed outputs to zero */
+
+#define IEEE_MAP_MASK		(IEEE_MAP_DMZ | IEEE_MAP_UMZ)
+
+/* status bits coming from fpcr: */
+#define IEEE_STATUS_INV		(1UL<<17)
+#define IEEE_STATUS_DZE		(1UL<<18)
+#define IEEE_STATUS_OVF		(1UL<<19)
+#define IEEE_STATUS_UNF		(1UL<<20)
+#define IEEE_STATUS_INE		(1UL<<21)
+#define IEEE_STATUS_DNO		(1UL<<22)
+
+#define IEEE_STATUS_MASK	(IEEE_STATUS_INV | IEEE_STATUS_DZE |	\
+				 IEEE_STATUS_OVF | IEEE_STATUS_UNF |	\
+				 IEEE_STATUS_INE | IEEE_STATUS_DNO)
+
+#define IEEE_SW_MASK		(IEEE_TRAP_ENABLE_MASK |		\
+				 IEEE_STATUS_MASK | IEEE_MAP_MASK)
+
+#define IEEE_CURRENT_RM_SHIFT	32
+#define IEEE_CURRENT_RM_MASK	(3UL<<IEEE_CURRENT_RM_SHIFT)
+
+#define IEEE_STATUS_TO_EXCSUM_SHIFT	16
+
+#define IEEE_INHERIT    (1UL<<63)	/* inherit on thread create? */
+
+/*
+ * Convert the software IEEE trap enable and status bits into the
+ * hardware fpcr format. 
+ *
+ * Digital Unix engineers receive my thanks for not defining the
+ * software bits identical to the hardware bits.  The chip designers
+ * receive my thanks for making all the not-implemented fpcr bits
+ * RAZ forcing us to use system calls to read/write this value.
+ */
+
+static inline unsigned long
+ieee_swcr_to_fpcr(unsigned long sw)
+{
+	unsigned long fp;
+	fp = (sw & IEEE_STATUS_MASK) << 35;
+	fp |= (sw & IEEE_MAP_DMZ) << 36;
+	fp |= (sw & IEEE_STATUS_MASK ? FPCR_SUM : 0);
+	fp |= (~sw & (IEEE_TRAP_ENABLE_INV
+		      | IEEE_TRAP_ENABLE_DZE
+		      | IEEE_TRAP_ENABLE_OVF)) << 48;
+	fp |= (~sw & (IEEE_TRAP_ENABLE_UNF | IEEE_TRAP_ENABLE_INE)) << 57;
+	fp |= (sw & IEEE_MAP_UMZ ? FPCR_UNDZ | FPCR_UNFD : 0);
+	fp |= (~sw & IEEE_TRAP_ENABLE_DNO) << 41;
+	return fp;
+}
+
+static inline unsigned long
+ieee_fpcr_to_swcr(unsigned long fp)
+{
+	unsigned long sw;
+	sw = (fp >> 35) & IEEE_STATUS_MASK;
+	sw |= (fp >> 36) & IEEE_MAP_DMZ;
+	sw |= (~fp >> 48) & (IEEE_TRAP_ENABLE_INV
+			     | IEEE_TRAP_ENABLE_DZE
+			     | IEEE_TRAP_ENABLE_OVF);
+	sw |= (~fp >> 57) & (IEEE_TRAP_ENABLE_UNF | IEEE_TRAP_ENABLE_INE);
+	sw |= (fp >> 47) & IEEE_MAP_UMZ;
+	sw |= (~fp >> 41) & IEEE_TRAP_ENABLE_DNO;
+	return sw;
+}
+
+#ifdef __KERNEL__
+
+/* The following two functions don't need trapb/excb instructions
+   around the mf_fpcr/mt_fpcr instructions because (a) the kernel
+   never generates arithmetic faults and (b) call_pal instructions
+   are implied trap barriers.  */
+
+static inline unsigned long
+rdfpcr(void)
+{
+	unsigned long tmp, ret;
+
+#if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67)
+	__asm__ __volatile__ (
+		"ftoit $f0,%0\n\t"
+		"mf_fpcr $f0\n\t"
+		"ftoit $f0,%1\n\t"
+		"itoft %0,$f0"
+		: "=r"(tmp), "=r"(ret));
+#else
+	__asm__ __volatile__ (
+		"stt $f0,%0\n\t"
+		"mf_fpcr $f0\n\t"
+		"stt $f0,%1\n\t"
+		"ldt $f0,%0"
+		: "=m"(tmp), "=m"(ret));
+#endif
+
+	return ret;
+}
+
+static inline void
+wrfpcr(unsigned long val)
+{
+	unsigned long tmp;
+
+#if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67)
+	__asm__ __volatile__ (
+		"ftoit $f0,%0\n\t"
+		"itoft %1,$f0\n\t"
+		"mt_fpcr $f0\n\t"
+		"itoft %0,$f0"
+		: "=&r"(tmp) : "r"(val));
+#else
+	__asm__ __volatile__ (
+		"stt $f0,%0\n\t"
+		"ldt $f0,%1\n\t"
+		"mt_fpcr $f0\n\t"
+		"ldt $f0,%0"
+		: "=m"(tmp) : "m"(val));
+#endif
+}
+
+static inline unsigned long
+swcr_update_status(unsigned long swcr, unsigned long fpcr)
+{
+	/* EV6 implements most of the bits in hardware.  Collect
+	   the acrued exception bits from the real fpcr.  */
+	if (implver() == IMPLVER_EV6) {
+		swcr &= ~IEEE_STATUS_MASK;
+		swcr |= (fpcr >> 35) & IEEE_STATUS_MASK;
+	}
+	return swcr;
+}
+
+extern unsigned long alpha_read_fp_reg (unsigned long reg);
+extern void alpha_write_fp_reg (unsigned long reg, unsigned long val);
+extern unsigned long alpha_read_fp_reg_s (unsigned long reg);
+extern void alpha_write_fp_reg_s (unsigned long reg, unsigned long val);
+
+#endif /* __KERNEL__ */
+
+#endif /* __ASM_ALPHA_FPU_H */