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-rw-r--r--arch/sh/math-emu/Makefile2
-rw-r--r--arch/sh/math-emu/math.c506
-rw-r--r--arch/sh/math-emu/sfp-util.h69
3 files changed, 577 insertions, 0 deletions
diff --git a/arch/sh/math-emu/Makefile b/arch/sh/math-emu/Makefile
new file mode 100644
index 000000000..ba06e42c4
--- /dev/null
+++ b/arch/sh/math-emu/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-y := math.o
diff --git a/arch/sh/math-emu/math.c b/arch/sh/math-emu/math.c
new file mode 100644
index 000000000..615ba932c
--- /dev/null
+++ b/arch/sh/math-emu/math.c
@@ -0,0 +1,506 @@
+/*
+ * arch/sh/math-emu/math.c
+ *
+ * Copyright (C) 2006 Takashi YOSHII <takasi-y@ops.dti.ne.jp>
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/sched/signal.h>
+#include <linux/signal.h>
+#include <linux/perf_event.h>
+
+#include <linux/uaccess.h>
+#include <asm/processor.h>
+#include <asm/io.h>
+
+#include "sfp-util.h"
+#include <math-emu/soft-fp.h>
+#include <math-emu/single.h>
+#include <math-emu/double.h>
+
+#define FPUL (fregs->fpul)
+#define FPSCR (fregs->fpscr)
+#define FPSCR_RM (FPSCR&3)
+#define FPSCR_DN ((FPSCR>>18)&1)
+#define FPSCR_PR ((FPSCR>>19)&1)
+#define FPSCR_SZ ((FPSCR>>20)&1)
+#define FPSCR_FR ((FPSCR>>21)&1)
+#define FPSCR_MASK 0x003fffffUL
+
+#define BANK(n) (n^(FPSCR_FR?16:0))
+#define FR ((unsigned long*)(fregs->fp_regs))
+#define FR0 (FR[BANK(0)])
+#define FRn (FR[BANK(n)])
+#define FRm (FR[BANK(m)])
+#define DR ((unsigned long long*)(fregs->fp_regs))
+#define DRn (DR[BANK(n)/2])
+#define DRm (DR[BANK(m)/2])
+
+#define XREG(n) (n^16)
+#define XFn (FR[BANK(XREG(n))])
+#define XFm (FR[BANK(XREG(m))])
+#define XDn (DR[BANK(XREG(n))/2])
+#define XDm (DR[BANK(XREG(m))/2])
+
+#define R0 (regs->regs[0])
+#define Rn (regs->regs[n])
+#define Rm (regs->regs[m])
+
+#define WRITE(d,a) ({if(put_user(d, (typeof (d)*)a)) return -EFAULT;})
+#define READ(d,a) ({if(get_user(d, (typeof (d)*)a)) return -EFAULT;})
+
+#define PACK_S(r,f) FP_PACK_SP(&r,f)
+#define UNPACK_S(f,r) FP_UNPACK_SP(f,&r)
+#define PACK_D(r,f) \
+ {u32 t[2]; FP_PACK_DP(t,f); ((u32*)&r)[0]=t[1]; ((u32*)&r)[1]=t[0];}
+#define UNPACK_D(f,r) \
+ {u32 t[2]; t[0]=((u32*)&r)[1]; t[1]=((u32*)&r)[0]; FP_UNPACK_DP(f,t);}
+
+// 2 args instructions.
+#define BOTH_PRmn(op,x) \
+ FP_DECL_EX; if(FPSCR_PR) op(D,x,DRm,DRn); else op(S,x,FRm,FRn);
+
+#define CMP_X(SZ,R,M,N) do{ \
+ FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); \
+ UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \
+ FP_CMP_##SZ(R, Fn, Fm, 2); }while(0)
+#define EQ_X(SZ,R,M,N) do{ \
+ FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); \
+ UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \
+ FP_CMP_EQ_##SZ(R, Fn, Fm); }while(0)
+#define CMP(OP) ({ int r; BOTH_PRmn(OP##_X,r); r; })
+
+static int
+fcmp_gt(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
+{
+ if (CMP(CMP) > 0)
+ regs->sr |= 1;
+ else
+ regs->sr &= ~1;
+
+ return 0;
+}
+
+static int
+fcmp_eq(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
+{
+ if (CMP(CMP /*EQ*/) == 0)
+ regs->sr |= 1;
+ else
+ regs->sr &= ~1;
+ return 0;
+}
+
+#define ARITH_X(SZ,OP,M,N) do{ \
+ FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); FP_DECL_##SZ(Fr); \
+ UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \
+ FP_##OP##_##SZ(Fr, Fn, Fm); \
+ PACK_##SZ(N, Fr); }while(0)
+
+static int
+fadd(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
+{
+ BOTH_PRmn(ARITH_X, ADD);
+ return 0;
+}
+
+static int
+fsub(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
+{
+ BOTH_PRmn(ARITH_X, SUB);
+ return 0;
+}
+
+static int
+fmul(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
+{
+ BOTH_PRmn(ARITH_X, MUL);
+ return 0;
+}
+
+static int
+fdiv(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
+{
+ BOTH_PRmn(ARITH_X, DIV);
+ return 0;
+}
+
+static int
+fmac(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
+{
+ FP_DECL_EX;
+ FP_DECL_S(Fr);
+ FP_DECL_S(Ft);
+ FP_DECL_S(F0);
+ FP_DECL_S(Fm);
+ FP_DECL_S(Fn);
+ UNPACK_S(F0, FR0);
+ UNPACK_S(Fm, FRm);
+ UNPACK_S(Fn, FRn);
+ FP_MUL_S(Ft, Fm, F0);
+ FP_ADD_S(Fr, Fn, Ft);
+ PACK_S(FRn, Fr);
+ return 0;
+}
+
+// to process fmov's extension (odd n for DR access XD).
+#define FMOV_EXT(x) if(x&1) x+=16-1
+
+static int
+fmov_idx_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
+ int n)
+{
+ if (FPSCR_SZ) {
+ FMOV_EXT(n);
+ READ(FRn, Rm + R0 + 4);
+ n++;
+ READ(FRn, Rm + R0);
+ } else {
+ READ(FRn, Rm + R0);
+ }
+
+ return 0;
+}
+
+static int
+fmov_mem_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
+ int n)
+{
+ if (FPSCR_SZ) {
+ FMOV_EXT(n);
+ READ(FRn, Rm + 4);
+ n++;
+ READ(FRn, Rm);
+ } else {
+ READ(FRn, Rm);
+ }
+
+ return 0;
+}
+
+static int
+fmov_inc_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
+ int n)
+{
+ if (FPSCR_SZ) {
+ FMOV_EXT(n);
+ READ(FRn, Rm + 4);
+ n++;
+ READ(FRn, Rm);
+ Rm += 8;
+ } else {
+ READ(FRn, Rm);
+ Rm += 4;
+ }
+
+ return 0;
+}
+
+static int
+fmov_reg_idx(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
+ int n)
+{
+ if (FPSCR_SZ) {
+ FMOV_EXT(m);
+ WRITE(FRm, Rn + R0 + 4);
+ m++;
+ WRITE(FRm, Rn + R0);
+ } else {
+ WRITE(FRm, Rn + R0);
+ }
+
+ return 0;
+}
+
+static int
+fmov_reg_mem(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
+ int n)
+{
+ if (FPSCR_SZ) {
+ FMOV_EXT(m);
+ WRITE(FRm, Rn + 4);
+ m++;
+ WRITE(FRm, Rn);
+ } else {
+ WRITE(FRm, Rn);
+ }
+
+ return 0;
+}
+
+static int
+fmov_reg_dec(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
+ int n)
+{
+ if (FPSCR_SZ) {
+ FMOV_EXT(m);
+ Rn -= 8;
+ WRITE(FRm, Rn + 4);
+ m++;
+ WRITE(FRm, Rn);
+ } else {
+ Rn -= 4;
+ WRITE(FRm, Rn);
+ }
+
+ return 0;
+}
+
+static int
+fmov_reg_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
+ int n)
+{
+ if (FPSCR_SZ) {
+ FMOV_EXT(m);
+ FMOV_EXT(n);
+ DRn = DRm;
+ } else {
+ FRn = FRm;
+ }
+
+ return 0;
+}
+
+static int
+fnop_mn(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
+{
+ return -EINVAL;
+}
+
+// 1 arg instructions.
+#define NOTYETn(i) static int i(struct sh_fpu_soft_struct *fregs, int n) \
+ { printk( #i " not yet done.\n"); return 0; }
+
+NOTYETn(ftrv)
+NOTYETn(fsqrt)
+NOTYETn(fipr)
+NOTYETn(fsca)
+NOTYETn(fsrra)
+
+#define EMU_FLOAT_X(SZ,N) do { \
+ FP_DECL_##SZ(Fn); \
+ FP_FROM_INT_##SZ(Fn, FPUL, 32, int); \
+ PACK_##SZ(N, Fn); }while(0)
+static int ffloat(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FP_DECL_EX;
+
+ if (FPSCR_PR)
+ EMU_FLOAT_X(D, DRn);
+ else
+ EMU_FLOAT_X(S, FRn);
+
+ return 0;
+}
+
+#define EMU_FTRC_X(SZ,N) do { \
+ FP_DECL_##SZ(Fn); \
+ UNPACK_##SZ(Fn, N); \
+ FP_TO_INT_##SZ(FPUL, Fn, 32, 1); }while(0)
+static int ftrc(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FP_DECL_EX;
+
+ if (FPSCR_PR)
+ EMU_FTRC_X(D, DRn);
+ else
+ EMU_FTRC_X(S, FRn);
+
+ return 0;
+}
+
+static int fcnvsd(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FP_DECL_EX;
+ FP_DECL_S(Fn);
+ FP_DECL_D(Fr);
+ UNPACK_S(Fn, FPUL);
+ FP_CONV(D, S, 2, 1, Fr, Fn);
+ PACK_D(DRn, Fr);
+ return 0;
+}
+
+static int fcnvds(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FP_DECL_EX;
+ FP_DECL_D(Fn);
+ FP_DECL_S(Fr);
+ UNPACK_D(Fn, DRn);
+ FP_CONV(S, D, 1, 2, Fr, Fn);
+ PACK_S(FPUL, Fr);
+ return 0;
+}
+
+static int fxchg(struct sh_fpu_soft_struct *fregs, int flag)
+{
+ FPSCR ^= flag;
+ return 0;
+}
+
+static int fsts(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FRn = FPUL;
+ return 0;
+}
+
+static int flds(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FPUL = FRn;
+ return 0;
+}
+
+static int fneg(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FRn ^= (1 << (_FP_W_TYPE_SIZE - 1));
+ return 0;
+}
+
+static int fabs(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FRn &= ~(1 << (_FP_W_TYPE_SIZE - 1));
+ return 0;
+}
+
+static int fld0(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FRn = 0;
+ return 0;
+}
+
+static int fld1(struct sh_fpu_soft_struct *fregs, int n)
+{
+ FRn = (_FP_EXPBIAS_S << (_FP_FRACBITS_S - 1));
+ return 0;
+}
+
+static int fnop_n(struct sh_fpu_soft_struct *fregs, int n)
+{
+ return -EINVAL;
+}
+
+/// Instruction decoders.
+
+static int id_fxfd(struct sh_fpu_soft_struct *, int);
+static int id_fnxd(struct sh_fpu_soft_struct *, struct pt_regs *, int, int);
+
+static int (*fnxd[])(struct sh_fpu_soft_struct *, int) = {
+ fsts, flds, ffloat, ftrc, fneg, fabs, fsqrt, fsrra,
+ fld0, fld1, fcnvsd, fcnvds, fnop_n, fnop_n, fipr, id_fxfd
+};
+
+static int (*fnmx[])(struct sh_fpu_soft_struct *, struct pt_regs *, int, int) = {
+ fadd, fsub, fmul, fdiv, fcmp_eq, fcmp_gt, fmov_idx_reg, fmov_reg_idx,
+ fmov_mem_reg, fmov_inc_reg, fmov_reg_mem, fmov_reg_dec,
+ fmov_reg_reg, id_fnxd, fmac, fnop_mn};
+
+static int id_fxfd(struct sh_fpu_soft_struct *fregs, int x)
+{
+ const int flag[] = { FPSCR_SZ, FPSCR_PR, FPSCR_FR, 0 };
+ switch (x & 3) {
+ case 3:
+ fxchg(fregs, flag[x >> 2]);
+ break;
+ case 1:
+ ftrv(fregs, x - 1);
+ break;
+ default:
+ fsca(fregs, x);
+ }
+ return 0;
+}
+
+static int
+id_fnxd(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int x, int n)
+{
+ return (fnxd[x])(fregs, n);
+}
+
+static int
+id_fnmx(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, u16 code)
+{
+ int n = (code >> 8) & 0xf, m = (code >> 4) & 0xf, x = code & 0xf;
+ return (fnmx[x])(fregs, regs, m, n);
+}
+
+static int
+id_sys(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, u16 code)
+{
+ int n = ((code >> 8) & 0xf);
+ unsigned long *reg = (code & 0x0010) ? &FPUL : &FPSCR;
+
+ switch (code & 0xf0ff) {
+ case 0x005a:
+ case 0x006a:
+ Rn = *reg;
+ break;
+ case 0x405a:
+ case 0x406a:
+ *reg = Rn;
+ break;
+ case 0x4052:
+ case 0x4062:
+ Rn -= 4;
+ WRITE(*reg, Rn);
+ break;
+ case 0x4056:
+ case 0x4066:
+ READ(*reg, Rn);
+ Rn += 4;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int fpu_emulate(u16 code, struct sh_fpu_soft_struct *fregs, struct pt_regs *regs)
+{
+ if ((code & 0xf000) == 0xf000)
+ return id_fnmx(fregs, regs, code);
+ else
+ return id_sys(fregs, regs, code);
+}
+
+/**
+ * fpu_init - Initialize FPU registers
+ * @fpu: Pointer to software emulated FPU registers.
+ */
+static void fpu_init(struct sh_fpu_soft_struct *fpu)
+{
+ int i;
+
+ fpu->fpscr = FPSCR_INIT;
+ fpu->fpul = 0;
+
+ for (i = 0; i < 16; i++) {
+ fpu->fp_regs[i] = 0;
+ fpu->xfp_regs[i]= 0;
+ }
+}
+
+/**
+ * do_fpu_inst - Handle reserved instructions for FPU emulation
+ * @inst: instruction code.
+ * @regs: registers on stack.
+ */
+int do_fpu_inst(unsigned short inst, struct pt_regs *regs)
+{
+ struct task_struct *tsk = current;
+ struct sh_fpu_soft_struct *fpu = &(tsk->thread.xstate->softfpu);
+
+ perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
+
+ if (!(task_thread_info(tsk)->status & TS_USEDFPU)) {
+ /* initialize once. */
+ fpu_init(fpu);
+ task_thread_info(tsk)->status |= TS_USEDFPU;
+ }
+
+ return fpu_emulate(inst, fpu, regs);
+}
diff --git a/arch/sh/math-emu/sfp-util.h b/arch/sh/math-emu/sfp-util.h
new file mode 100644
index 000000000..bda50762b
--- /dev/null
+++ b/arch/sh/math-emu/sfp-util.h
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * These are copied from glibc/stdlib/longlong.h
+ */
+
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+ do { \
+ UWtype __x; \
+ __x = (al) + (bl); \
+ (sh) = (ah) + (bh) + (__x < (al)); \
+ (sl) = __x; \
+ } while (0)
+
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+ do { \
+ UWtype __x; \
+ __x = (al) - (bl); \
+ (sh) = (ah) - (bh) - (__x > (al)); \
+ (sl) = __x; \
+ } while (0)
+
+#define umul_ppmm(w1, w0, u, v) \
+ __asm__ ("dmulu.l %2,%3\n\tsts macl,%1\n\tsts mach,%0" \
+ : "=r" ((u32)(w1)), "=r" ((u32)(w0)) \
+ : "r" ((u32)(u)), "r" ((u32)(v)) \
+ : "macl", "mach")
+
+#define __ll_B ((UWtype) 1 << (W_TYPE_SIZE / 2))
+#define __ll_lowpart(t) ((UWtype) (t) & (__ll_B - 1))
+#define __ll_highpart(t) ((UWtype) (t) >> (W_TYPE_SIZE / 2))
+
+#define udiv_qrnnd(q, r, n1, n0, d) \
+ do { \
+ UWtype __d1, __d0, __q1, __q0; \
+ UWtype __r1, __r0, __m; \
+ __d1 = __ll_highpart (d); \
+ __d0 = __ll_lowpart (d); \
+ \
+ __r1 = (n1) % __d1; \
+ __q1 = (n1) / __d1; \
+ __m = (UWtype) __q1 * __d0; \
+ __r1 = __r1 * __ll_B | __ll_highpart (n0); \
+ if (__r1 < __m) \
+ { \
+ __q1--, __r1 += (d); \
+ if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */\
+ if (__r1 < __m) \
+ __q1--, __r1 += (d); \
+ } \
+ __r1 -= __m; \
+ \
+ __r0 = __r1 % __d1; \
+ __q0 = __r1 / __d1; \
+ __m = (UWtype) __q0 * __d0; \
+ __r0 = __r0 * __ll_B | __ll_lowpart (n0); \
+ if (__r0 < __m) \
+ { \
+ __q0--, __r0 += (d); \
+ if (__r0 >= (d)) \
+ if (__r0 < __m) \
+ __q0--, __r0 += (d); \
+ } \
+ __r0 -= __m; \
+ \
+ (q) = (UWtype) __q1 * __ll_B | __q0; \
+ (r) = __r0; \
+ } while (0)
+
+#define abort() return 0