From 38db37ba069f9d801ef56b820cfc7c247a7ffc02 Mon Sep 17 00:00:00 2001 From: Markos Chandras Date: Thu, 13 Aug 2015 09:56:34 +0200 Subject: MIPS: math-emu: Add support for the MIPS R6 CLASS FPU instruction MIPS R6 introduced the following instruction: Stores in fd a bit mask reflecting the floating-point class of the floating point scalar value fs. CLASS.fmt: FPR[fd] = class(FPR[fs]) Signed-off-by: Markos Chandras Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10959/ Signed-off-by: Ralf Baechle --- arch/mips/math-emu/dp_2008class.c | 55 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 arch/mips/math-emu/dp_2008class.c (limited to 'arch/mips/math-emu/dp_2008class.c') diff --git a/arch/mips/math-emu/dp_2008class.c b/arch/mips/math-emu/dp_2008class.c new file mode 100644 index 000000000000..9dc39fc4835e --- /dev/null +++ b/arch/mips/math-emu/dp_2008class.c @@ -0,0 +1,55 @@ +/* + * IEEE754 floating point arithmetic + * double precision: CLASS.f + * FPR[fd] = class(FPR[fs]) + * + * MIPS floating point support + * Copyright (C) 2015 Imagination Technologies, Ltd. + * Author: Markos Chandras + * + * This program is free software; you can distribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; version 2 of the License. + */ + +#include "ieee754dp.h" + +int ieee754dp_2008class(union ieee754dp x) +{ + COMPXDP; + + EXPLODEXDP; + + /* + * 10 bit mask as follows: + * + * bit0 = SNAN + * bit1 = QNAN + * bit2 = -INF + * bit3 = -NORM + * bit4 = -DNORM + * bit5 = -ZERO + * bit6 = INF + * bit7 = NORM + * bit8 = DNORM + * bit9 = ZERO + */ + + switch(xc) { + case IEEE754_CLASS_SNAN: + return 0x01; + case IEEE754_CLASS_QNAN: + return 0x02; + case IEEE754_CLASS_INF: + return 0x04 << (xs ? 0 : 4); + case IEEE754_CLASS_NORM: + return 0x08 << (xs ? 0 : 4); + case IEEE754_CLASS_DNORM: + return 0x10 << (xs ? 0 : 4); + case IEEE754_CLASS_ZERO: + return 0x20 << (xs ? 0 : 4); + default: + pr_err("Unknown class: %d\n", xc); + return 0; + } +} -- cgit v1.2.3