diff options
Diffstat (limited to 'arch/sh64/kernel/fpu.c')
| -rw-r--r-- | arch/sh64/kernel/fpu.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/arch/sh64/kernel/fpu.c b/arch/sh64/kernel/fpu.c new file mode 100644 index 000000000000..8ad4ed6a6c9b --- /dev/null +++ b/arch/sh64/kernel/fpu.c @@ -0,0 +1,170 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * arch/sh64/kernel/fpu.c + * + * Copyright (C) 2001 Manuela Cirronis, Paolo Alberelli + * Copyright (C) 2002 STMicroelectronics Limited + * Author : Stuart Menefy + * + * Started from SH4 version: + * Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka + * + */ + +#include <linux/sched.h> +#include <linux/signal.h> +#include <asm/processor.h> +#include <asm/user.h> +#include <asm/io.h> + +/* + * Initially load the FPU with signalling NANS. This bit pattern + * has the property that no matter whether considered as single or as + * double precision, it still represents a signalling NAN. + */ +#define sNAN64 0xFFFFFFFFFFFFFFFFULL +#define sNAN32 0xFFFFFFFFUL + +static union sh_fpu_union init_fpuregs = { + .hard = { + .fp_regs = { [0 ... 63] = sNAN32 }, + .fpscr = FPSCR_INIT + } +}; + +inline void fpsave(struct sh_fpu_hard_struct *fpregs) +{ + asm volatile("fst.p %0, (0*8), fp0\n\t" + "fst.p %0, (1*8), fp2\n\t" + "fst.p %0, (2*8), fp4\n\t" + "fst.p %0, (3*8), fp6\n\t" + "fst.p %0, (4*8), fp8\n\t" + "fst.p %0, (5*8), fp10\n\t" + "fst.p %0, (6*8), fp12\n\t" + "fst.p %0, (7*8), fp14\n\t" + "fst.p %0, (8*8), fp16\n\t" + "fst.p %0, (9*8), fp18\n\t" + "fst.p %0, (10*8), fp20\n\t" + "fst.p %0, (11*8), fp22\n\t" + "fst.p %0, (12*8), fp24\n\t" + "fst.p %0, (13*8), fp26\n\t" + "fst.p %0, (14*8), fp28\n\t" + "fst.p %0, (15*8), fp30\n\t" + "fst.p %0, (16*8), fp32\n\t" + "fst.p %0, (17*8), fp34\n\t" + "fst.p %0, (18*8), fp36\n\t" + "fst.p %0, (19*8), fp38\n\t" + "fst.p %0, (20*8), fp40\n\t" + "fst.p %0, (21*8), fp42\n\t" + "fst.p %0, (22*8), fp44\n\t" + "fst.p %0, (23*8), fp46\n\t" + "fst.p %0, (24*8), fp48\n\t" + "fst.p %0, (25*8), fp50\n\t" + "fst.p %0, (26*8), fp52\n\t" + "fst.p %0, (27*8), fp54\n\t" + "fst.p %0, (28*8), fp56\n\t" + "fst.p %0, (29*8), fp58\n\t" + "fst.p %0, (30*8), fp60\n\t" + "fst.p %0, (31*8), fp62\n\t" + + "fgetscr fr63\n\t" + "fst.s %0, (32*8), fr63\n\t" + : /* no output */ + : "r" (fpregs) + : "memory"); +} + + +static inline void +fpload(struct sh_fpu_hard_struct *fpregs) +{ + asm volatile("fld.p %0, (0*8), fp0\n\t" + "fld.p %0, (1*8), fp2\n\t" + "fld.p %0, (2*8), fp4\n\t" + "fld.p %0, (3*8), fp6\n\t" + "fld.p %0, (4*8), fp8\n\t" + "fld.p %0, (5*8), fp10\n\t" + "fld.p %0, (6*8), fp12\n\t" + "fld.p %0, (7*8), fp14\n\t" + "fld.p %0, (8*8), fp16\n\t" + "fld.p %0, (9*8), fp18\n\t" + "fld.p %0, (10*8), fp20\n\t" + "fld.p %0, (11*8), fp22\n\t" + "fld.p %0, (12*8), fp24\n\t" + "fld.p %0, (13*8), fp26\n\t" + "fld.p %0, (14*8), fp28\n\t" + "fld.p %0, (15*8), fp30\n\t" + "fld.p %0, (16*8), fp32\n\t" + "fld.p %0, (17*8), fp34\n\t" + "fld.p %0, (18*8), fp36\n\t" + "fld.p %0, (19*8), fp38\n\t" + "fld.p %0, (20*8), fp40\n\t" + "fld.p %0, (21*8), fp42\n\t" + "fld.p %0, (22*8), fp44\n\t" + "fld.p %0, (23*8), fp46\n\t" + "fld.p %0, (24*8), fp48\n\t" + "fld.p %0, (25*8), fp50\n\t" + "fld.p %0, (26*8), fp52\n\t" + "fld.p %0, (27*8), fp54\n\t" + "fld.p %0, (28*8), fp56\n\t" + "fld.p %0, (29*8), fp58\n\t" + "fld.p %0, (30*8), fp60\n\t" + + "fld.s %0, (32*8), fr63\n\t" + "fputscr fr63\n\t" + + "fld.p %0, (31*8), fp62\n\t" + : /* no output */ + : "r" (fpregs) ); +} + +void fpinit(struct sh_fpu_hard_struct *fpregs) +{ + *fpregs = init_fpuregs.hard; +} + +asmlinkage void +do_fpu_error(unsigned long ex, struct pt_regs *regs) +{ + struct task_struct *tsk = current; + + regs->pc += 4; + + tsk->thread.trap_no = 11; + tsk->thread.error_code = 0; + force_sig(SIGFPE, tsk); +} + + +asmlinkage void +do_fpu_state_restore(unsigned long ex, struct pt_regs *regs) +{ + void die(const char *str, struct pt_regs *regs, long err); + + if (! user_mode(regs)) + die("FPU used in kernel", regs, ex); + + regs->sr &= ~SR_FD; + + if (last_task_used_math == current) + return; + + grab_fpu(); + if (last_task_used_math != NULL) { + /* Other processes fpu state, save away */ + fpsave(&last_task_used_math->thread.fpu.hard); + } + last_task_used_math = current; + if (used_math()) { + fpload(¤t->thread.fpu.hard); + } else { + /* First time FPU user. */ + fpload(&init_fpuregs.hard); + set_used_math(); + } + release_fpu(); +} + |