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-rw-r--r--arch/mips/kernel/r2300_fpu.S188
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diff --git a/arch/mips/kernel/r2300_fpu.S b/arch/mips/kernel/r2300_fpu.S
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+/*
+ * 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.
+ *
+ * Copyright (C) 1996, 1998 by Ralf Baechle
+ *
+ * Multi-arch abstraction and asm macros for easier reading:
+ * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
+ *
+ * Further modifications to make this work:
+ * Copyright (c) 1998 Harald Koerfgen
+ */
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/errno.h>
+#include <asm/export.h>
+#include <asm/fpregdef.h>
+#include <asm/mipsregs.h>
+#include <asm/asm-offsets.h>
+#include <asm/regdef.h>
+
+#define EX(a,b) \
+9: a,##b; \
+ .section __ex_table,"a"; \
+ PTR 9b,fault; \
+ .previous
+
+#define EX2(a,b) \
+9: a,##b; \
+ .section __ex_table,"a"; \
+ PTR 9b,fault; \
+ PTR 9b+4,fault; \
+ .previous
+
+ .set mips1
+
+/*
+ * Save a thread's fp context.
+ */
+LEAF(_save_fp)
+EXPORT_SYMBOL(_save_fp)
+ fpu_save_single a0, t1 # clobbers t1
+ jr ra
+ END(_save_fp)
+
+/*
+ * Restore a thread's fp context.
+ */
+LEAF(_restore_fp)
+ fpu_restore_single a0, t1 # clobbers t1
+ jr ra
+ END(_restore_fp)
+
+/*
+ * Load the FPU with signalling NANS. This bit pattern we're using has
+ * the property that no matter whether considered as single or as double
+ * precision represents signaling NANS.
+ *
+ * The value to initialize fcr31 to comes in $a0.
+ */
+
+ .set push
+ SET_HARDFLOAT
+
+LEAF(_init_fpu)
+ mfc0 t0, CP0_STATUS
+ li t1, ST0_CU1
+ or t0, t1
+ mtc0 t0, CP0_STATUS
+
+ ctc1 a0, fcr31
+
+ li t0, -1
+
+ mtc1 t0, $f0
+ mtc1 t0, $f1
+ mtc1 t0, $f2
+ mtc1 t0, $f3
+ mtc1 t0, $f4
+ mtc1 t0, $f5
+ mtc1 t0, $f6
+ mtc1 t0, $f7
+ mtc1 t0, $f8
+ mtc1 t0, $f9
+ mtc1 t0, $f10
+ mtc1 t0, $f11
+ mtc1 t0, $f12
+ mtc1 t0, $f13
+ mtc1 t0, $f14
+ mtc1 t0, $f15
+ mtc1 t0, $f16
+ mtc1 t0, $f17
+ mtc1 t0, $f18
+ mtc1 t0, $f19
+ mtc1 t0, $f20
+ mtc1 t0, $f21
+ mtc1 t0, $f22
+ mtc1 t0, $f23
+ mtc1 t0, $f24
+ mtc1 t0, $f25
+ mtc1 t0, $f26
+ mtc1 t0, $f27
+ mtc1 t0, $f28
+ mtc1 t0, $f29
+ mtc1 t0, $f30
+ mtc1 t0, $f31
+ jr ra
+ END(_init_fpu)
+
+ .set pop
+
+ .set noreorder
+
+/**
+ * _save_fp_context() - save FP context from the FPU
+ * @a0 - pointer to fpregs field of sigcontext
+ * @a1 - pointer to fpc_csr field of sigcontext
+ *
+ * Save FP context, including the 32 FP data registers and the FP
+ * control & status register, from the FPU to signal context.
+ */
+LEAF(_save_fp_context)
+ .set push
+ SET_HARDFLOAT
+ li v0, 0 # assume success
+ cfc1 t1, fcr31
+ EX2(s.d $f0, 0(a0))
+ EX2(s.d $f2, 16(a0))
+ EX2(s.d $f4, 32(a0))
+ EX2(s.d $f6, 48(a0))
+ EX2(s.d $f8, 64(a0))
+ EX2(s.d $f10, 80(a0))
+ EX2(s.d $f12, 96(a0))
+ EX2(s.d $f14, 112(a0))
+ EX2(s.d $f16, 128(a0))
+ EX2(s.d $f18, 144(a0))
+ EX2(s.d $f20, 160(a0))
+ EX2(s.d $f22, 176(a0))
+ EX2(s.d $f24, 192(a0))
+ EX2(s.d $f26, 208(a0))
+ EX2(s.d $f28, 224(a0))
+ EX2(s.d $f30, 240(a0))
+ jr ra
+ EX(sw t1, (a1))
+ .set pop
+ END(_save_fp_context)
+
+/**
+ * _restore_fp_context() - restore FP context to the FPU
+ * @a0 - pointer to fpregs field of sigcontext
+ * @a1 - pointer to fpc_csr field of sigcontext
+ *
+ * Restore FP context, including the 32 FP data registers and the FP
+ * control & status register, from signal context to the FPU.
+ */
+LEAF(_restore_fp_context)
+ .set push
+ SET_HARDFLOAT
+ li v0, 0 # assume success
+ EX(lw t0, (a1))
+ EX2(l.d $f0, 0(a0))
+ EX2(l.d $f2, 16(a0))
+ EX2(l.d $f4, 32(a0))
+ EX2(l.d $f6, 48(a0))
+ EX2(l.d $f8, 64(a0))
+ EX2(l.d $f10, 80(a0))
+ EX2(l.d $f12, 96(a0))
+ EX2(l.d $f14, 112(a0))
+ EX2(l.d $f16, 128(a0))
+ EX2(l.d $f18, 144(a0))
+ EX2(l.d $f20, 160(a0))
+ EX2(l.d $f22, 176(a0))
+ EX2(l.d $f24, 192(a0))
+ EX2(l.d $f26, 208(a0))
+ EX2(l.d $f28, 224(a0))
+ EX2(l.d $f30, 240(a0))
+ jr ra
+ ctc1 t0, fcr31
+ .set pop
+ END(_restore_fp_context)
+ .set reorder
+
+ .type fault, @function
+ .ent fault
+fault: li v0, -EFAULT
+ jr ra
+ .end fault