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-rw-r--r--arch/powerpc/math-emu/math.c461
1 files changed, 461 insertions, 0 deletions
diff --git a/arch/powerpc/math-emu/math.c b/arch/powerpc/math-emu/math.c
new file mode 100644
index 0000000000..936a9a1490
--- /dev/null
+++ b/arch/powerpc/math-emu/math.c
@@ -0,0 +1,461 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 1999 Eddie C. Dost (ecd@atecom.com)
+ */
+
+#include <linux/types.h>
+#include <linux/sched.h>
+
+#include <linux/uaccess.h>
+#include <asm/reg.h>
+#include <asm/switch_to.h>
+
+#include <asm/sfp-machine.h>
+#include <math-emu/double.h>
+
+#define FLOATFUNC(x) extern int x(void *, void *, void *, void *)
+
+/* The instructions list which may be not implemented by a hardware FPU */
+FLOATFUNC(fre);
+FLOATFUNC(frsqrtes);
+FLOATFUNC(fsqrt);
+FLOATFUNC(fsqrts);
+FLOATFUNC(mtfsf);
+FLOATFUNC(mtfsfi);
+
+#ifdef CONFIG_MATH_EMULATION_HW_UNIMPLEMENTED
+#undef FLOATFUNC
+#define FLOATFUNC(x) static inline int x(void *op1, void *op2, void *op3, \
+ void *op4) { return 0; }
+#endif
+
+FLOATFUNC(fadd);
+FLOATFUNC(fadds);
+FLOATFUNC(fdiv);
+FLOATFUNC(fdivs);
+FLOATFUNC(fmul);
+FLOATFUNC(fmuls);
+FLOATFUNC(fsub);
+FLOATFUNC(fsubs);
+
+FLOATFUNC(fmadd);
+FLOATFUNC(fmadds);
+FLOATFUNC(fmsub);
+FLOATFUNC(fmsubs);
+FLOATFUNC(fnmadd);
+FLOATFUNC(fnmadds);
+FLOATFUNC(fnmsub);
+FLOATFUNC(fnmsubs);
+
+FLOATFUNC(fctiw);
+FLOATFUNC(fctiwz);
+FLOATFUNC(frsp);
+
+FLOATFUNC(fcmpo);
+FLOATFUNC(fcmpu);
+
+FLOATFUNC(mcrfs);
+FLOATFUNC(mffs);
+FLOATFUNC(mtfsb0);
+FLOATFUNC(mtfsb1);
+
+FLOATFUNC(lfd);
+FLOATFUNC(lfs);
+
+FLOATFUNC(stfd);
+FLOATFUNC(stfs);
+FLOATFUNC(stfiwx);
+
+FLOATFUNC(fabs);
+FLOATFUNC(fmr);
+FLOATFUNC(fnabs);
+FLOATFUNC(fneg);
+
+/* Optional */
+FLOATFUNC(fres);
+FLOATFUNC(frsqrte);
+FLOATFUNC(fsel);
+
+
+#define OP31 0x1f /* 31 */
+#define LFS 0x30 /* 48 */
+#define LFSU 0x31 /* 49 */
+#define LFD 0x32 /* 50 */
+#define LFDU 0x33 /* 51 */
+#define STFS 0x34 /* 52 */
+#define STFSU 0x35 /* 53 */
+#define STFD 0x36 /* 54 */
+#define STFDU 0x37 /* 55 */
+#define OP59 0x3b /* 59 */
+#define OP63 0x3f /* 63 */
+
+/* Opcode 31: */
+/* X-Form: */
+#define LFSX 0x217 /* 535 */
+#define LFSUX 0x237 /* 567 */
+#define LFDX 0x257 /* 599 */
+#define LFDUX 0x277 /* 631 */
+#define STFSX 0x297 /* 663 */
+#define STFSUX 0x2b7 /* 695 */
+#define STFDX 0x2d7 /* 727 */
+#define STFDUX 0x2f7 /* 759 */
+#define STFIWX 0x3d7 /* 983 */
+
+/* Opcode 59: */
+/* A-Form: */
+#define FDIVS 0x012 /* 18 */
+#define FSUBS 0x014 /* 20 */
+#define FADDS 0x015 /* 21 */
+#define FSQRTS 0x016 /* 22 */
+#define FRES 0x018 /* 24 */
+#define FMULS 0x019 /* 25 */
+#define FRSQRTES 0x01a /* 26 */
+#define FMSUBS 0x01c /* 28 */
+#define FMADDS 0x01d /* 29 */
+#define FNMSUBS 0x01e /* 30 */
+#define FNMADDS 0x01f /* 31 */
+
+/* Opcode 63: */
+/* A-Form: */
+#define FDIV 0x012 /* 18 */
+#define FSUB 0x014 /* 20 */
+#define FADD 0x015 /* 21 */
+#define FSQRT 0x016 /* 22 */
+#define FSEL 0x017 /* 23 */
+#define FRE 0x018 /* 24 */
+#define FMUL 0x019 /* 25 */
+#define FRSQRTE 0x01a /* 26 */
+#define FMSUB 0x01c /* 28 */
+#define FMADD 0x01d /* 29 */
+#define FNMSUB 0x01e /* 30 */
+#define FNMADD 0x01f /* 31 */
+
+/* X-Form: */
+#define FCMPU 0x000 /* 0 */
+#define FRSP 0x00c /* 12 */
+#define FCTIW 0x00e /* 14 */
+#define FCTIWZ 0x00f /* 15 */
+#define FCMPO 0x020 /* 32 */
+#define MTFSB1 0x026 /* 38 */
+#define FNEG 0x028 /* 40 */
+#define MCRFS 0x040 /* 64 */
+#define MTFSB0 0x046 /* 70 */
+#define FMR 0x048 /* 72 */
+#define MTFSFI 0x086 /* 134 */
+#define FNABS 0x088 /* 136 */
+#define FABS 0x108 /* 264 */
+#define MFFS 0x247 /* 583 */
+#define MTFSF 0x2c7 /* 711 */
+
+
+#define AB 2
+#define AC 3
+#define ABC 4
+#define D 5
+#define DU 6
+#define X 7
+#define XA 8
+#define XB 9
+#define XCR 11
+#define XCRB 12
+#define XCRI 13
+#define XCRL 16
+#define XE 14
+#define XEU 15
+#define XFLB 10
+
+static int
+record_exception(struct pt_regs *regs, int eflag)
+{
+ u32 fpscr;
+
+ fpscr = __FPU_FPSCR;
+
+ if (eflag) {
+ fpscr |= FPSCR_FX;
+ if (eflag & EFLAG_OVERFLOW)
+ fpscr |= FPSCR_OX;
+ if (eflag & EFLAG_UNDERFLOW)
+ fpscr |= FPSCR_UX;
+ if (eflag & EFLAG_DIVZERO)
+ fpscr |= FPSCR_ZX;
+ if (eflag & EFLAG_INEXACT)
+ fpscr |= FPSCR_XX;
+ if (eflag & EFLAG_INVALID)
+ fpscr |= FPSCR_VX;
+ if (eflag & EFLAG_VXSNAN)
+ fpscr |= FPSCR_VXSNAN;
+ if (eflag & EFLAG_VXISI)
+ fpscr |= FPSCR_VXISI;
+ if (eflag & EFLAG_VXIDI)
+ fpscr |= FPSCR_VXIDI;
+ if (eflag & EFLAG_VXZDZ)
+ fpscr |= FPSCR_VXZDZ;
+ if (eflag & EFLAG_VXIMZ)
+ fpscr |= FPSCR_VXIMZ;
+ if (eflag & EFLAG_VXVC)
+ fpscr |= FPSCR_VXVC;
+ if (eflag & EFLAG_VXSOFT)
+ fpscr |= FPSCR_VXSOFT;
+ if (eflag & EFLAG_VXSQRT)
+ fpscr |= FPSCR_VXSQRT;
+ if (eflag & EFLAG_VXCVI)
+ fpscr |= FPSCR_VXCVI;
+ }
+
+// fpscr &= ~(FPSCR_VX);
+ if (fpscr & (FPSCR_VXSNAN | FPSCR_VXISI | FPSCR_VXIDI |
+ FPSCR_VXZDZ | FPSCR_VXIMZ | FPSCR_VXVC |
+ FPSCR_VXSOFT | FPSCR_VXSQRT | FPSCR_VXCVI))
+ fpscr |= FPSCR_VX;
+
+ fpscr &= ~(FPSCR_FEX);
+ if (((fpscr & FPSCR_VX) && (fpscr & FPSCR_VE)) ||
+ ((fpscr & FPSCR_OX) && (fpscr & FPSCR_OE)) ||
+ ((fpscr & FPSCR_UX) && (fpscr & FPSCR_UE)) ||
+ ((fpscr & FPSCR_ZX) && (fpscr & FPSCR_ZE)) ||
+ ((fpscr & FPSCR_XX) && (fpscr & FPSCR_XE)))
+ fpscr |= FPSCR_FEX;
+
+ __FPU_FPSCR = fpscr;
+
+ return (fpscr & FPSCR_FEX) ? 1 : 0;
+}
+
+int
+do_mathemu(struct pt_regs *regs)
+{
+ void *op0 = NULL, *op1 = NULL, *op2 = NULL, *op3 = NULL;
+ unsigned long pc = regs->nip;
+ signed short sdisp;
+ u32 insn = 0;
+ int idx = 0;
+ int (*func)(void *, void *, void *, void *);
+ int type = 0;
+ int eflag, trap;
+
+ if (get_user(insn, (u32 __user *)pc))
+ return -EFAULT;
+
+ switch (insn >> 26) {
+ case LFS: func = lfs; type = D; break;
+ case LFSU: func = lfs; type = DU; break;
+ case LFD: func = lfd; type = D; break;
+ case LFDU: func = lfd; type = DU; break;
+ case STFS: func = stfs; type = D; break;
+ case STFSU: func = stfs; type = DU; break;
+ case STFD: func = stfd; type = D; break;
+ case STFDU: func = stfd; type = DU; break;
+
+ case OP31:
+ switch ((insn >> 1) & 0x3ff) {
+ case LFSX: func = lfs; type = XE; break;
+ case LFSUX: func = lfs; type = XEU; break;
+ case LFDX: func = lfd; type = XE; break;
+ case LFDUX: func = lfd; type = XEU; break;
+ case STFSX: func = stfs; type = XE; break;
+ case STFSUX: func = stfs; type = XEU; break;
+ case STFDX: func = stfd; type = XE; break;
+ case STFDUX: func = stfd; type = XEU; break;
+ case STFIWX: func = stfiwx; type = XE; break;
+ default:
+ goto illegal;
+ }
+ break;
+
+ case OP59:
+ switch ((insn >> 1) & 0x1f) {
+ case FDIVS: func = fdivs; type = AB; break;
+ case FSUBS: func = fsubs; type = AB; break;
+ case FADDS: func = fadds; type = AB; break;
+ case FSQRTS: func = fsqrts; type = XB; break;
+ case FRES: func = fres; type = XB; break;
+ case FMULS: func = fmuls; type = AC; break;
+ case FRSQRTES: func = frsqrtes;type = XB; break;
+ case FMSUBS: func = fmsubs; type = ABC; break;
+ case FMADDS: func = fmadds; type = ABC; break;
+ case FNMSUBS: func = fnmsubs; type = ABC; break;
+ case FNMADDS: func = fnmadds; type = ABC; break;
+ default:
+ goto illegal;
+ }
+ break;
+
+ case OP63:
+ if (insn & 0x20) {
+ switch ((insn >> 1) & 0x1f) {
+ case FDIV: func = fdiv; type = AB; break;
+ case FSUB: func = fsub; type = AB; break;
+ case FADD: func = fadd; type = AB; break;
+ case FSQRT: func = fsqrt; type = XB; break;
+ case FRE: func = fre; type = XB; break;
+ case FSEL: func = fsel; type = ABC; break;
+ case FMUL: func = fmul; type = AC; break;
+ case FRSQRTE: func = frsqrte; type = XB; break;
+ case FMSUB: func = fmsub; type = ABC; break;
+ case FMADD: func = fmadd; type = ABC; break;
+ case FNMSUB: func = fnmsub; type = ABC; break;
+ case FNMADD: func = fnmadd; type = ABC; break;
+ default:
+ goto illegal;
+ }
+ break;
+ }
+
+ switch ((insn >> 1) & 0x3ff) {
+ case FCMPU: func = fcmpu; type = XCR; break;
+ case FRSP: func = frsp; type = XB; break;
+ case FCTIW: func = fctiw; type = XB; break;
+ case FCTIWZ: func = fctiwz; type = XB; break;
+ case FCMPO: func = fcmpo; type = XCR; break;
+ case MTFSB1: func = mtfsb1; type = XCRB; break;
+ case FNEG: func = fneg; type = XB; break;
+ case MCRFS: func = mcrfs; type = XCRL; break;
+ case MTFSB0: func = mtfsb0; type = XCRB; break;
+ case FMR: func = fmr; type = XB; break;
+ case MTFSFI: func = mtfsfi; type = XCRI; break;
+ case FNABS: func = fnabs; type = XB; break;
+ case FABS: func = fabs; type = XB; break;
+ case MFFS: func = mffs; type = X; break;
+ case MTFSF: func = mtfsf; type = XFLB; break;
+ default:
+ goto illegal;
+ }
+ break;
+
+ default:
+ goto illegal;
+ }
+
+ switch (type) {
+ case AB:
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ op1 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+ op2 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+ break;
+
+ case AC:
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ op1 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+ op2 = (void *)&current->thread.TS_FPR((insn >> 6) & 0x1f);
+ break;
+
+ case ABC:
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ op1 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+ op2 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+ op3 = (void *)&current->thread.TS_FPR((insn >> 6) & 0x1f);
+ break;
+
+ case D:
+ idx = (insn >> 16) & 0x1f;
+ sdisp = (insn & 0xffff);
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ op1 = (void *)((idx ? regs->gpr[idx] : 0) + sdisp);
+ break;
+
+ case DU:
+ idx = (insn >> 16) & 0x1f;
+ if (!idx)
+ goto illegal;
+
+ sdisp = (insn & 0xffff);
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ op1 = (void *)(regs->gpr[idx] + sdisp);
+ break;
+
+ case X:
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ break;
+
+ case XA:
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ op1 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+ break;
+
+ case XB:
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ op1 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+ break;
+
+ case XE:
+ idx = (insn >> 16) & 0x1f;
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ op1 = (void *)((idx ? regs->gpr[idx] : 0)
+ + regs->gpr[(insn >> 11) & 0x1f]);
+ break;
+
+ case XEU:
+ idx = (insn >> 16) & 0x1f;
+ if (!idx)
+ goto illegal;
+ op0 = (void *)&current->thread.TS_FPR((insn >> 21) & 0x1f);
+ op1 = (void *)(regs->gpr[idx]
+ + regs->gpr[(insn >> 11) & 0x1f]);
+ break;
+
+ case XCR:
+ op0 = (void *)&regs->ccr;
+ op1 = (void *)(long)((insn >> 23) & 0x7);
+ op2 = (void *)&current->thread.TS_FPR((insn >> 16) & 0x1f);
+ op3 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+ break;
+
+ case XCRL:
+ op0 = (void *)&regs->ccr;
+ op1 = (void *)(long)((insn >> 23) & 0x7);
+ op2 = (void *)(long)((insn >> 18) & 0x7);
+ break;
+
+ case XCRB:
+ op0 = (void *)(long)((insn >> 21) & 0x1f);
+ break;
+
+ case XCRI:
+ op0 = (void *)(long)((insn >> 23) & 0x7);
+ op1 = (void *)(long)((insn >> 12) & 0xf);
+ break;
+
+ case XFLB:
+ op0 = (void *)(long)((insn >> 17) & 0xff);
+ op1 = (void *)&current->thread.TS_FPR((insn >> 11) & 0x1f);
+ break;
+
+ default:
+ goto illegal;
+ }
+
+ /*
+ * If we support a HW FPU, we need to ensure the FP state
+ * is flushed into the thread_struct before attempting
+ * emulation
+ */
+ flush_fp_to_thread(current);
+
+ eflag = func(op0, op1, op2, op3);
+
+ if (insn & 1) {
+ regs->ccr &= ~(0x0f000000);
+ regs->ccr |= (__FPU_FPSCR >> 4) & 0x0f000000;
+ }
+
+ trap = record_exception(regs, eflag);
+ if (trap)
+ return 1;
+
+ switch (type) {
+ case DU:
+ case XEU:
+ regs->gpr[idx] = (unsigned long)op1;
+ break;
+
+ default:
+ break;
+ }
+
+ regs_add_return_ip(regs, 4);
+ return 0;
+
+illegal:
+ return -ENOSYS;
+}
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