aboutsummaryrefslogtreecommitdiffstats
path: root/arch/nds32/math-emu/fpuemu.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/nds32/math-emu/fpuemu.c')
-rw-r--r--arch/nds32/math-emu/fpuemu.c352
1 files changed, 352 insertions, 0 deletions
diff --git a/arch/nds32/math-emu/fpuemu.c b/arch/nds32/math-emu/fpuemu.c
new file mode 100644
index 000000000000..2a01333d6e5f
--- /dev/null
+++ b/arch/nds32/math-emu/fpuemu.c
@@ -0,0 +1,352 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2018 Andes Technology Corporation
+
+#include <asm/bitfield.h>
+#include <asm/uaccess.h>
+#include <asm/sfp-machine.h>
+#include <asm/fpuemu.h>
+#include <asm/nds32_fpu_inst.h>
+
+#define DPFROMREG(dp, x) (dp = (void *)((unsigned long *)fpu_reg + 2*x))
+#ifdef __NDS32_EL__
+#define SPFROMREG(sp, x)\
+ ((sp) = (void *)((unsigned long *)fpu_reg + (x^1)))
+#else
+#define SPFROMREG(sp, x) ((sp) = (void *)((unsigned long *)fpu_reg + x))
+#endif
+
+#define DEF3OP(name, p, f1, f2) \
+void fpemu_##name##p(void *ft, void *fa, void *fb) \
+{ \
+ f1(fa, fa, fb); \
+ f2(ft, ft, fa); \
+}
+
+#define DEF3OPNEG(name, p, f1, f2, f3) \
+void fpemu_##name##p(void *ft, void *fa, void *fb) \
+{ \
+ f1(fa, fa, fb); \
+ f2(ft, ft, fa); \
+ f3(ft, ft); \
+}
+DEF3OP(fmadd, s, fmuls, fadds);
+DEF3OP(fmsub, s, fmuls, fsubs);
+DEF3OP(fmadd, d, fmuld, faddd);
+DEF3OP(fmsub, d, fmuld, fsubd);
+DEF3OPNEG(fnmadd, s, fmuls, fadds, fnegs);
+DEF3OPNEG(fnmsub, s, fmuls, fsubs, fnegs);
+DEF3OPNEG(fnmadd, d, fmuld, faddd, fnegd);
+DEF3OPNEG(fnmsub, d, fmuld, fsubd, fnegd);
+
+static const unsigned char cmptab[8] = {
+ SF_CEQ,
+ SF_CEQ,
+ SF_CLT,
+ SF_CLT,
+ SF_CLT | SF_CEQ,
+ SF_CLT | SF_CEQ,
+ SF_CUN,
+ SF_CUN
+};
+
+enum ARGTYPE {
+ S1S = 1,
+ S2S,
+ S1D,
+ CS,
+ D1D,
+ D2D,
+ D1S,
+ CD
+};
+union func_t {
+ void (*t)(void *ft, void *fa, void *fb);
+ void (*b)(void *ft, void *fa);
+};
+/*
+ * Emulate a single FPU arithmetic instruction.
+ */
+static int fpu_emu(struct fpu_struct *fpu_reg, unsigned long insn)
+{
+ int rfmt; /* resulting format */
+ union func_t func;
+ int ftype = 0;
+
+ switch (rfmt = NDS32Insn_OPCODE_COP0(insn)) {
+ case fs1_op:{
+ switch (NDS32Insn_OPCODE_BIT69(insn)) {
+ case fadds_op:
+ func.t = fadds;
+ ftype = S2S;
+ break;
+ case fsubs_op:
+ func.t = fsubs;
+ ftype = S2S;
+ break;
+ case fmadds_op:
+ func.t = fpemu_fmadds;
+ ftype = S2S;
+ break;
+ case fmsubs_op:
+ func.t = fpemu_fmsubs;
+ ftype = S2S;
+ break;
+ case fnmadds_op:
+ func.t = fpemu_fnmadds;
+ ftype = S2S;
+ break;
+ case fnmsubs_op:
+ func.t = fpemu_fnmsubs;
+ ftype = S2S;
+ break;
+ case fmuls_op:
+ func.t = fmuls;
+ ftype = S2S;
+ break;
+ case fdivs_op:
+ func.t = fdivs;
+ ftype = S2S;
+ break;
+ case fs1_f2op_op:
+ switch (NDS32Insn_OPCODE_BIT1014(insn)) {
+ case fs2d_op:
+ func.b = fs2d;
+ ftype = S1D;
+ break;
+ case fsqrts_op:
+ func.b = fsqrts;
+ ftype = S1S;
+ break;
+ default:
+ return SIGILL;
+ }
+ break;
+ default:
+ return SIGILL;
+ }
+ break;
+ }
+ case fs2_op:
+ switch (NDS32Insn_OPCODE_BIT69(insn)) {
+ case fcmpeqs_op:
+ case fcmpeqs_e_op:
+ case fcmplts_op:
+ case fcmplts_e_op:
+ case fcmples_op:
+ case fcmples_e_op:
+ case fcmpuns_op:
+ case fcmpuns_e_op:
+ ftype = CS;
+ break;
+ default:
+ return SIGILL;
+ }
+ break;
+ case fd1_op:{
+ switch (NDS32Insn_OPCODE_BIT69(insn)) {
+ case faddd_op:
+ func.t = faddd;
+ ftype = D2D;
+ break;
+ case fsubd_op:
+ func.t = fsubd;
+ ftype = D2D;
+ break;
+ case fmaddd_op:
+ func.t = fpemu_fmaddd;
+ ftype = D2D;
+ break;
+ case fmsubd_op:
+ func.t = fpemu_fmsubd;
+ ftype = D2D;
+ break;
+ case fnmaddd_op:
+ func.t = fpemu_fnmaddd;
+ ftype = D2D;
+ break;
+ case fnmsubd_op:
+ func.t = fpemu_fnmsubd;
+ ftype = D2D;
+ break;
+ case fmuld_op:
+ func.t = fmuld;
+ ftype = D2D;
+ break;
+ case fdivd_op:
+ func.t = fdivd;
+ ftype = D2D;
+ break;
+ case fd1_f2op_op:
+ switch (NDS32Insn_OPCODE_BIT1014(insn)) {
+ case fd2s_op:
+ func.b = fd2s;
+ ftype = D1S;
+ break;
+ case fsqrtd_op:
+ func.b = fsqrtd;
+ ftype = D1D;
+ break;
+ default:
+ return SIGILL;
+ }
+ break;
+ default:
+ return SIGILL;
+
+ }
+ break;
+ }
+
+ case fd2_op:
+ switch (NDS32Insn_OPCODE_BIT69(insn)) {
+ case fcmpeqd_op:
+ case fcmpeqd_e_op:
+ case fcmpltd_op:
+ case fcmpltd_e_op:
+ case fcmpled_op:
+ case fcmpled_e_op:
+ case fcmpund_op:
+ case fcmpund_e_op:
+ ftype = CD;
+ break;
+ default:
+ return SIGILL;
+ }
+ break;
+
+ default:
+ return SIGILL;
+ }
+
+ switch (ftype) {
+ case S1S:{
+ void *ft, *fa;
+
+ SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn));
+ SPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn));
+ func.b(ft, fa);
+ break;
+ }
+ case S2S:{
+ void *ft, *fa, *fb;
+
+ SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn));
+ SPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn));
+ SPFROMREG(fb, NDS32Insn_OPCODE_Rb(insn));
+ func.t(ft, fa, fb);
+ break;
+ }
+ case S1D:{
+ void *ft, *fa;
+
+ DPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn));
+ SPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn));
+ func.b(ft, fa);
+ break;
+ }
+ case CS:{
+ unsigned int cmpop = NDS32Insn_OPCODE_BIT69(insn);
+ void *ft, *fa, *fb;
+
+ SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn));
+ SPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn));
+ SPFROMREG(fb, NDS32Insn_OPCODE_Rb(insn));
+ if (cmpop < 0x8) {
+ cmpop = cmptab[cmpop];
+ fcmps(ft, fa, fb, cmpop);
+ } else
+ return SIGILL;
+ break;
+ }
+ case D1D:{
+ void *ft, *fa;
+
+ DPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn));
+ DPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn));
+ func.b(ft, fa);
+ break;
+ }
+ case D2D:{
+ void *ft, *fa, *fb;
+
+ DPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn));
+ DPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn));
+ DPFROMREG(fb, NDS32Insn_OPCODE_Rb(insn));
+ func.t(ft, fa, fb);
+ break;
+ }
+ case D1S:{
+ void *ft, *fa;
+
+ SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn));
+ DPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn));
+ func.b(ft, fa);
+ break;
+ }
+ case CD:{
+ unsigned int cmpop = NDS32Insn_OPCODE_BIT69(insn);
+ void *ft, *fa, *fb;
+
+ SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn));
+ DPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn));
+ DPFROMREG(fb, NDS32Insn_OPCODE_Rb(insn));
+ if (cmpop < 0x8) {
+ cmpop = cmptab[cmpop];
+ fcmpd(ft, fa, fb, cmpop);
+ } else
+ return SIGILL;
+ break;
+ }
+ default:
+ return SIGILL;
+ }
+
+ /*
+ * If an exception is required, generate a tidy SIGFPE exception.
+ */
+ if ((fpu_reg->fpcsr << 5) & fpu_reg->fpcsr & FPCSR_mskALLE)
+ return SIGFPE;
+ return 0;
+}
+
+
+int do_fpuemu(struct pt_regs *regs, struct fpu_struct *fpu)
+{
+ unsigned long insn = 0, addr = regs->ipc;
+ unsigned long emulpc, contpc;
+ unsigned char *pc = (void *)&insn;
+ char c;
+ int i = 0, ret;
+
+ for (i = 0; i < 4; i++) {
+ if (__get_user(c, (unsigned char *)addr++))
+ return SIGBUS;
+ *pc++ = c;
+ }
+
+ insn = be32_to_cpu(insn);
+
+ emulpc = regs->ipc;
+ contpc = regs->ipc + 4;
+
+ if (NDS32Insn_OPCODE(insn) != cop0_op)
+ return SIGILL;
+ switch (NDS32Insn_OPCODE_COP0(insn)) {
+ case fs1_op:
+ case fs2_op:
+ case fd1_op:
+ case fd2_op:
+ {
+ /* a real fpu computation instruction */
+ ret = fpu_emu(fpu, insn);
+ if (!ret)
+ regs->ipc = contpc;
+ }
+ break;
+
+ default:
+ return SIGILL;
+ }
+
+ return ret;
+}