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-rw-r--r--arch/sh64/kernel/fpu.c170
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(&current->thread.fpu.hard);
+ } else {
+ /* First time FPU user. */
+ fpload(&init_fpuregs.hard);
+ set_used_math();
+ }
+ release_fpu();
+}
+