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-rw-r--r--arch/mips/math-emu/cp1emu.c2929
1 files changed, 2929 insertions, 0 deletions
diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c
new file mode 100644
index 000000000..62deb0259
--- /dev/null
+++ b/arch/mips/math-emu/cp1emu.c
@@ -0,0 +1,2929 @@
+/*
+ * cp1emu.c: a MIPS coprocessor 1 (FPU) instruction emulator
+ *
+ * MIPS floating point support
+ * Copyright (C) 1994-2000 Algorithmics Ltd.
+ *
+ * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 2000 MIPS Technologies, Inc.
+ *
+ * This program is free software; you can distribute it and/or modify it
+ * under the terms of the GNU General Public License (Version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * A complete emulator for MIPS coprocessor 1 instructions. This is
+ * required for #float(switch) or #float(trap), where it catches all
+ * COP1 instructions via the "CoProcessor Unusable" exception.
+ *
+ * More surprisingly it is also required for #float(ieee), to help out
+ * the hardware FPU at the boundaries of the IEEE-754 representation
+ * (denormalised values, infinities, underflow, etc). It is made
+ * quite nasty because emulation of some non-COP1 instructions is
+ * required, e.g. in branch delay slots.
+ *
+ * Note if you know that you won't have an FPU, then you'll get much
+ * better performance by compiling with -msoft-float!
+ */
+#include <linux/sched.h>
+#include <linux/debugfs.h>
+#include <linux/percpu-defs.h>
+#include <linux/perf_event.h>
+
+#include <asm/branch.h>
+#include <asm/inst.h>
+#include <asm/ptrace.h>
+#include <asm/signal.h>
+#include <linux/uaccess.h>
+
+#include <asm/cpu-info.h>
+#include <asm/processor.h>
+#include <asm/fpu_emulator.h>
+#include <asm/fpu.h>
+#include <asm/mips-r2-to-r6-emul.h>
+
+#include "ieee754.h"
+
+/* Function which emulates a floating point instruction. */
+
+static int fpu_emu(struct pt_regs *, struct mips_fpu_struct *,
+ mips_instruction);
+
+static int fpux_emu(struct pt_regs *,
+ struct mips_fpu_struct *, mips_instruction, void __user **);
+
+/* Control registers */
+
+#define FPCREG_RID 0 /* $0 = revision id */
+#define FPCREG_FCCR 25 /* $25 = fccr */
+#define FPCREG_FEXR 26 /* $26 = fexr */
+#define FPCREG_FENR 28 /* $28 = fenr */
+#define FPCREG_CSR 31 /* $31 = csr */
+
+/* convert condition code register number to csr bit */
+const unsigned int fpucondbit[8] = {
+ FPU_CSR_COND,
+ FPU_CSR_COND1,
+ FPU_CSR_COND2,
+ FPU_CSR_COND3,
+ FPU_CSR_COND4,
+ FPU_CSR_COND5,
+ FPU_CSR_COND6,
+ FPU_CSR_COND7
+};
+
+/* (microMIPS) Convert certain microMIPS instructions to MIPS32 format. */
+static const int sd_format[] = {16, 17, 0, 0, 0, 0, 0, 0};
+static const int sdps_format[] = {16, 17, 22, 0, 0, 0, 0, 0};
+static const int dwl_format[] = {17, 20, 21, 0, 0, 0, 0, 0};
+static const int swl_format[] = {16, 20, 21, 0, 0, 0, 0, 0};
+
+/*
+ * This functions translates a 32-bit microMIPS instruction
+ * into a 32-bit MIPS32 instruction. Returns 0 on success
+ * and SIGILL otherwise.
+ */
+static int microMIPS32_to_MIPS32(union mips_instruction *insn_ptr)
+{
+ union mips_instruction insn = *insn_ptr;
+ union mips_instruction mips32_insn = insn;
+ int func, fmt, op;
+
+ switch (insn.mm_i_format.opcode) {
+ case mm_ldc132_op:
+ mips32_insn.mm_i_format.opcode = ldc1_op;
+ mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
+ mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
+ break;
+ case mm_lwc132_op:
+ mips32_insn.mm_i_format.opcode = lwc1_op;
+ mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
+ mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
+ break;
+ case mm_sdc132_op:
+ mips32_insn.mm_i_format.opcode = sdc1_op;
+ mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
+ mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
+ break;
+ case mm_swc132_op:
+ mips32_insn.mm_i_format.opcode = swc1_op;
+ mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
+ mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
+ break;
+ case mm_pool32i_op:
+ /* NOTE: offset is << by 1 if in microMIPS mode. */
+ if ((insn.mm_i_format.rt == mm_bc1f_op) ||
+ (insn.mm_i_format.rt == mm_bc1t_op)) {
+ mips32_insn.fb_format.opcode = cop1_op;
+ mips32_insn.fb_format.bc = bc_op;
+ mips32_insn.fb_format.flag =
+ (insn.mm_i_format.rt == mm_bc1t_op) ? 1 : 0;
+ } else
+ return SIGILL;
+ break;
+ case mm_pool32f_op:
+ switch (insn.mm_fp0_format.func) {
+ case mm_32f_01_op:
+ case mm_32f_11_op:
+ case mm_32f_02_op:
+ case mm_32f_12_op:
+ case mm_32f_41_op:
+ case mm_32f_51_op:
+ case mm_32f_42_op:
+ case mm_32f_52_op:
+ op = insn.mm_fp0_format.func;
+ if (op == mm_32f_01_op)
+ func = madd_s_op;
+ else if (op == mm_32f_11_op)
+ func = madd_d_op;
+ else if (op == mm_32f_02_op)
+ func = nmadd_s_op;
+ else if (op == mm_32f_12_op)
+ func = nmadd_d_op;
+ else if (op == mm_32f_41_op)
+ func = msub_s_op;
+ else if (op == mm_32f_51_op)
+ func = msub_d_op;
+ else if (op == mm_32f_42_op)
+ func = nmsub_s_op;
+ else
+ func = nmsub_d_op;
+ mips32_insn.fp6_format.opcode = cop1x_op;
+ mips32_insn.fp6_format.fr = insn.mm_fp6_format.fr;
+ mips32_insn.fp6_format.ft = insn.mm_fp6_format.ft;
+ mips32_insn.fp6_format.fs = insn.mm_fp6_format.fs;
+ mips32_insn.fp6_format.fd = insn.mm_fp6_format.fd;
+ mips32_insn.fp6_format.func = func;
+ break;
+ case mm_32f_10_op:
+ func = -1; /* Invalid */
+ op = insn.mm_fp5_format.op & 0x7;
+ if (op == mm_ldxc1_op)
+ func = ldxc1_op;
+ else if (op == mm_sdxc1_op)
+ func = sdxc1_op;
+ else if (op == mm_lwxc1_op)
+ func = lwxc1_op;
+ else if (op == mm_swxc1_op)
+ func = swxc1_op;
+
+ if (func != -1) {
+ mips32_insn.r_format.opcode = cop1x_op;
+ mips32_insn.r_format.rs =
+ insn.mm_fp5_format.base;
+ mips32_insn.r_format.rt =
+ insn.mm_fp5_format.index;
+ mips32_insn.r_format.rd = 0;
+ mips32_insn.r_format.re = insn.mm_fp5_format.fd;
+ mips32_insn.r_format.func = func;
+ } else
+ return SIGILL;
+ break;
+ case mm_32f_40_op:
+ op = -1; /* Invalid */
+ if (insn.mm_fp2_format.op == mm_fmovt_op)
+ op = 1;
+ else if (insn.mm_fp2_format.op == mm_fmovf_op)
+ op = 0;
+ if (op != -1) {
+ mips32_insn.fp0_format.opcode = cop1_op;
+ mips32_insn.fp0_format.fmt =
+ sdps_format[insn.mm_fp2_format.fmt];
+ mips32_insn.fp0_format.ft =
+ (insn.mm_fp2_format.cc<<2) + op;
+ mips32_insn.fp0_format.fs =
+ insn.mm_fp2_format.fs;
+ mips32_insn.fp0_format.fd =
+ insn.mm_fp2_format.fd;
+ mips32_insn.fp0_format.func = fmovc_op;
+ } else
+ return SIGILL;
+ break;
+ case mm_32f_60_op:
+ func = -1; /* Invalid */
+ if (insn.mm_fp0_format.op == mm_fadd_op)
+ func = fadd_op;
+ else if (insn.mm_fp0_format.op == mm_fsub_op)
+ func = fsub_op;
+ else if (insn.mm_fp0_format.op == mm_fmul_op)
+ func = fmul_op;
+ else if (insn.mm_fp0_format.op == mm_fdiv_op)
+ func = fdiv_op;
+ if (func != -1) {
+ mips32_insn.fp0_format.opcode = cop1_op;
+ mips32_insn.fp0_format.fmt =
+ sdps_format[insn.mm_fp0_format.fmt];
+ mips32_insn.fp0_format.ft =
+ insn.mm_fp0_format.ft;
+ mips32_insn.fp0_format.fs =
+ insn.mm_fp0_format.fs;
+ mips32_insn.fp0_format.fd =
+ insn.mm_fp0_format.fd;
+ mips32_insn.fp0_format.func = func;
+ } else
+ return SIGILL;
+ break;
+ case mm_32f_70_op:
+ func = -1; /* Invalid */
+ if (insn.mm_fp0_format.op == mm_fmovn_op)
+ func = fmovn_op;
+ else if (insn.mm_fp0_format.op == mm_fmovz_op)
+ func = fmovz_op;
+ if (func != -1) {
+ mips32_insn.fp0_format.opcode = cop1_op;
+ mips32_insn.fp0_format.fmt =
+ sdps_format[insn.mm_fp0_format.fmt];
+ mips32_insn.fp0_format.ft =
+ insn.mm_fp0_format.ft;
+ mips32_insn.fp0_format.fs =
+ insn.mm_fp0_format.fs;
+ mips32_insn.fp0_format.fd =
+ insn.mm_fp0_format.fd;
+ mips32_insn.fp0_format.func = func;
+ } else
+ return SIGILL;
+ break;
+ case mm_32f_73_op: /* POOL32FXF */
+ switch (insn.mm_fp1_format.op) {
+ case mm_movf0_op:
+ case mm_movf1_op:
+ case mm_movt0_op:
+ case mm_movt1_op:
+ if ((insn.mm_fp1_format.op & 0x7f) ==
+ mm_movf0_op)
+ op = 0;
+ else
+ op = 1;
+ mips32_insn.r_format.opcode = spec_op;
+ mips32_insn.r_format.rs = insn.mm_fp4_format.fs;
+ mips32_insn.r_format.rt =
+ (insn.mm_fp4_format.cc << 2) + op;
+ mips32_insn.r_format.rd = insn.mm_fp4_format.rt;
+ mips32_insn.r_format.re = 0;
+ mips32_insn.r_format.func = movc_op;
+ break;
+ case mm_fcvtd0_op:
+ case mm_fcvtd1_op:
+ case mm_fcvts0_op:
+ case mm_fcvts1_op:
+ if ((insn.mm_fp1_format.op & 0x7f) ==
+ mm_fcvtd0_op) {
+ func = fcvtd_op;
+ fmt = swl_format[insn.mm_fp3_format.fmt];
+ } else {
+ func = fcvts_op;
+ fmt = dwl_format[insn.mm_fp3_format.fmt];
+ }
+ mips32_insn.fp0_format.opcode = cop1_op;
+ mips32_insn.fp0_format.fmt = fmt;
+ mips32_insn.fp0_format.ft = 0;
+ mips32_insn.fp0_format.fs =
+ insn.mm_fp3_format.fs;
+ mips32_insn.fp0_format.fd =
+ insn.mm_fp3_format.rt;
+ mips32_insn.fp0_format.func = func;
+ break;
+ case mm_fmov0_op:
+ case mm_fmov1_op:
+ case mm_fabs0_op:
+ case mm_fabs1_op:
+ case mm_fneg0_op:
+ case mm_fneg1_op:
+ if ((insn.mm_fp1_format.op & 0x7f) ==
+ mm_fmov0_op)
+ func = fmov_op;
+ else if ((insn.mm_fp1_format.op & 0x7f) ==
+ mm_fabs0_op)
+ func = fabs_op;
+ else
+ func = fneg_op;
+ mips32_insn.fp0_format.opcode = cop1_op;
+ mips32_insn.fp0_format.fmt =
+ sdps_format[insn.mm_fp3_format.fmt];
+ mips32_insn.fp0_format.ft = 0;
+ mips32_insn.fp0_format.fs =
+ insn.mm_fp3_format.fs;
+ mips32_insn.fp0_format.fd =
+ insn.mm_fp3_format.rt;
+ mips32_insn.fp0_format.func = func;
+ break;
+ case mm_ffloorl_op:
+ case mm_ffloorw_op:
+ case mm_fceill_op:
+ case mm_fceilw_op:
+ case mm_ftruncl_op:
+ case mm_ftruncw_op:
+ case mm_froundl_op:
+ case mm_froundw_op:
+ case mm_fcvtl_op:
+ case mm_fcvtw_op:
+ if (insn.mm_fp1_format.op == mm_ffloorl_op)
+ func = ffloorl_op;
+ else if (insn.mm_fp1_format.op == mm_ffloorw_op)
+ func = ffloor_op;
+ else if (insn.mm_fp1_format.op == mm_fceill_op)
+ func = fceill_op;
+ else if (insn.mm_fp1_format.op == mm_fceilw_op)
+ func = fceil_op;
+ else if (insn.mm_fp1_format.op == mm_ftruncl_op)
+ func = ftruncl_op;
+ else if (insn.mm_fp1_format.op == mm_ftruncw_op)
+ func = ftrunc_op;
+ else if (insn.mm_fp1_format.op == mm_froundl_op)
+ func = froundl_op;
+ else if (insn.mm_fp1_format.op == mm_froundw_op)
+ func = fround_op;
+ else if (insn.mm_fp1_format.op == mm_fcvtl_op)
+ func = fcvtl_op;
+ else
+ func = fcvtw_op;
+ mips32_insn.fp0_format.opcode = cop1_op;
+ mips32_insn.fp0_format.fmt =
+ sd_format[insn.mm_fp1_format.fmt];
+ mips32_insn.fp0_format.ft = 0;
+ mips32_insn.fp0_format.fs =
+ insn.mm_fp1_format.fs;
+ mips32_insn.fp0_format.fd =
+ insn.mm_fp1_format.rt;
+ mips32_insn.fp0_format.func = func;
+ break;
+ case mm_frsqrt_op:
+ case mm_fsqrt_op:
+ case mm_frecip_op:
+ if (insn.mm_fp1_format.op == mm_frsqrt_op)
+ func = frsqrt_op;
+ else if (insn.mm_fp1_format.op == mm_fsqrt_op)
+ func = fsqrt_op;
+ else
+ func = frecip_op;
+ mips32_insn.fp0_format.opcode = cop1_op;
+ mips32_insn.fp0_format.fmt =
+ sdps_format[insn.mm_fp1_format.fmt];
+ mips32_insn.fp0_format.ft = 0;
+ mips32_insn.fp0_format.fs =
+ insn.mm_fp1_format.fs;
+ mips32_insn.fp0_format.fd =
+ insn.mm_fp1_format.rt;
+ mips32_insn.fp0_format.func = func;
+ break;
+ case mm_mfc1_op:
+ case mm_mtc1_op:
+ case mm_cfc1_op:
+ case mm_ctc1_op:
+ case mm_mfhc1_op:
+ case mm_mthc1_op:
+ if (insn.mm_fp1_format.op == mm_mfc1_op)
+ op = mfc_op;
+ else if (insn.mm_fp1_format.op == mm_mtc1_op)
+ op = mtc_op;
+ else if (insn.mm_fp1_format.op == mm_cfc1_op)
+ op = cfc_op;
+ else if (insn.mm_fp1_format.op == mm_ctc1_op)
+ op = ctc_op;
+ else if (insn.mm_fp1_format.op == mm_mfhc1_op)
+ op = mfhc_op;
+ else
+ op = mthc_op;
+ mips32_insn.fp1_format.opcode = cop1_op;
+ mips32_insn.fp1_format.op = op;
+ mips32_insn.fp1_format.rt =
+ insn.mm_fp1_format.rt;
+ mips32_insn.fp1_format.fs =
+ insn.mm_fp1_format.fs;
+ mips32_insn.fp1_format.fd = 0;
+ mips32_insn.fp1_format.func = 0;
+ break;
+ default:
+ return SIGILL;
+ }
+ break;
+ case mm_32f_74_op: /* c.cond.fmt */
+ mips32_insn.fp0_format.opcode = cop1_op;
+ mips32_insn.fp0_format.fmt =
+ sdps_format[insn.mm_fp4_format.fmt];
+ mips32_insn.fp0_format.ft = insn.mm_fp4_format.rt;
+ mips32_insn.fp0_format.fs = insn.mm_fp4_format.fs;
+ mips32_insn.fp0_format.fd = insn.mm_fp4_format.cc << 2;
+ mips32_insn.fp0_format.func =
+ insn.mm_fp4_format.cond | MM_MIPS32_COND_FC;
+ break;
+ default:
+ return SIGILL;
+ }
+ break;
+ default:
+ return SIGILL;
+ }
+
+ *insn_ptr = mips32_insn;
+ return 0;
+}
+
+/*
+ * Redundant with logic already in kernel/branch.c,
+ * embedded in compute_return_epc. At some point,
+ * a single subroutine should be used across both
+ * modules.
+ */
+int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
+ unsigned long *contpc)
+{
+ union mips_instruction insn = (union mips_instruction)dec_insn.insn;
+ unsigned int fcr31;
+ unsigned int bit = 0;
+ unsigned int bit0;
+ union fpureg *fpr;
+
+ switch (insn.i_format.opcode) {
+ case spec_op:
+ switch (insn.r_format.func) {
+ case jalr_op:
+ if (insn.r_format.rd != 0) {
+ regs->regs[insn.r_format.rd] =
+ regs->cp0_epc + dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ }
+ /* fall through */
+ case jr_op:
+ /* For R6, JR already emulated in jalr_op */
+ if (NO_R6EMU && insn.r_format.func == jr_op)
+ break;
+ *contpc = regs->regs[insn.r_format.rs];
+ return 1;
+ }
+ break;
+ case bcond_op:
+ switch (insn.i_format.rt) {
+ case bltzal_op:
+ case bltzall_op:
+ if (NO_R6EMU && (insn.i_format.rs ||
+ insn.i_format.rt == bltzall_op))
+ break;
+
+ regs->regs[31] = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ /* fall through */
+ case bltzl_op:
+ if (NO_R6EMU)
+ break;
+ /* fall through */
+ case bltz_op:
+ if ((long)regs->regs[insn.i_format.rs] < 0)
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ return 1;
+ case bgezal_op:
+ case bgezall_op:
+ if (NO_R6EMU && (insn.i_format.rs ||
+ insn.i_format.rt == bgezall_op))
+ break;
+
+ regs->regs[31] = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ /* fall through */
+ case bgezl_op:
+ if (NO_R6EMU)
+ break;
+ /* fall through */
+ case bgez_op:
+ if ((long)regs->regs[insn.i_format.rs] >= 0)
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ return 1;
+ }
+ break;
+ case jalx_op:
+ set_isa16_mode(bit);
+ /* fall through */
+ case jal_op:
+ regs->regs[31] = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ /* fall through */
+ case j_op:
+ *contpc = regs->cp0_epc + dec_insn.pc_inc;
+ *contpc >>= 28;
+ *contpc <<= 28;
+ *contpc |= (insn.j_format.target << 2);
+ /* Set microMIPS mode bit: XOR for jalx. */
+ *contpc ^= bit;
+ return 1;
+ case beql_op:
+ if (NO_R6EMU)
+ break;
+ /* fall through */
+ case beq_op:
+ if (regs->regs[insn.i_format.rs] ==
+ regs->regs[insn.i_format.rt])
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ return 1;
+ case bnel_op:
+ if (NO_R6EMU)
+ break;
+ /* fall through */
+ case bne_op:
+ if (regs->regs[insn.i_format.rs] !=
+ regs->regs[insn.i_format.rt])
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ return 1;
+ case blezl_op:
+ if (!insn.i_format.rt && NO_R6EMU)
+ break;
+ /* fall through */
+ case blez_op:
+
+ /*
+ * Compact branches for R6 for the
+ * blez and blezl opcodes.
+ * BLEZ | rs = 0 | rt != 0 == BLEZALC
+ * BLEZ | rs = rt != 0 == BGEZALC
+ * BLEZ | rs != 0 | rt != 0 == BGEUC
+ * BLEZL | rs = 0 | rt != 0 == BLEZC
+ * BLEZL | rs = rt != 0 == BGEZC
+ * BLEZL | rs != 0 | rt != 0 == BGEC
+ *
+ * For real BLEZ{,L}, rt is always 0.
+ */
+ if (cpu_has_mips_r6 && insn.i_format.rt) {
+ if ((insn.i_format.opcode == blez_op) &&
+ ((!insn.i_format.rs && insn.i_format.rt) ||
+ (insn.i_format.rs == insn.i_format.rt)))
+ regs->regs[31] = regs->cp0_epc +
+ dec_insn.pc_inc;
+ *contpc = regs->cp0_epc + dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+
+ return 1;
+ }
+ if ((long)regs->regs[insn.i_format.rs] <= 0)
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ return 1;
+ case bgtzl_op:
+ if (!insn.i_format.rt && NO_R6EMU)
+ break;
+ /* fall through */
+ case bgtz_op:
+ /*
+ * Compact branches for R6 for the
+ * bgtz and bgtzl opcodes.
+ * BGTZ | rs = 0 | rt != 0 == BGTZALC
+ * BGTZ | rs = rt != 0 == BLTZALC
+ * BGTZ | rs != 0 | rt != 0 == BLTUC
+ * BGTZL | rs = 0 | rt != 0 == BGTZC
+ * BGTZL | rs = rt != 0 == BLTZC
+ * BGTZL | rs != 0 | rt != 0 == BLTC
+ *
+ * *ZALC varint for BGTZ &&& rt != 0
+ * For real GTZ{,L}, rt is always 0.
+ */
+ if (cpu_has_mips_r6 && insn.i_format.rt) {
+ if ((insn.i_format.opcode == blez_op) &&
+ ((!insn.i_format.rs && insn.i_format.rt) ||
+ (insn.i_format.rs == insn.i_format.rt)))
+ regs->regs[31] = regs->cp0_epc +
+ dec_insn.pc_inc;
+ *contpc = regs->cp0_epc + dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+
+ return 1;
+ }
+
+ if ((long)regs->regs[insn.i_format.rs] > 0)
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ return 1;
+ case pop10_op:
+ case pop30_op:
+ if (!cpu_has_mips_r6)
+ break;
+ if (insn.i_format.rt && !insn.i_format.rs)
+ regs->regs[31] = regs->cp0_epc + 4;
+ *contpc = regs->cp0_epc + dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+
+ return 1;
+#ifdef CONFIG_CPU_CAVIUM_OCTEON
+ case lwc2_op: /* This is bbit0 on Octeon */
+ if ((regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt)) == 0)
+ *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc + 8;
+ return 1;
+ case ldc2_op: /* This is bbit032 on Octeon */
+ if ((regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32))) == 0)
+ *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc + 8;
+ return 1;
+ case swc2_op: /* This is bbit1 on Octeon */
+ if (regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt))
+ *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc + 8;
+ return 1;
+ case sdc2_op: /* This is bbit132 on Octeon */
+ if (regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32)))
+ *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc + 8;
+ return 1;
+#else
+ case bc6_op:
+ /*
+ * Only valid for MIPS R6 but we can still end up
+ * here from a broken userland so just tell emulator
+ * this is not a branch and let it break later on.
+ */
+ if (!cpu_has_mips_r6)
+ break;
+ *contpc = regs->cp0_epc + dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+
+ return 1;
+ case balc6_op:
+ if (!cpu_has_mips_r6)
+ break;
+ regs->regs[31] = regs->cp0_epc + 4;
+ *contpc = regs->cp0_epc + dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+
+ return 1;
+ case pop66_op:
+ if (!cpu_has_mips_r6)
+ break;
+ *contpc = regs->cp0_epc + dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+
+ return 1;
+ case pop76_op:
+ if (!cpu_has_mips_r6)
+ break;
+ if (!insn.i_format.rs)
+ regs->regs[31] = regs->cp0_epc + 4;
+ *contpc = regs->cp0_epc + dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+
+ return 1;
+#endif
+ case cop0_op:
+ case cop1_op:
+ /* Need to check for R6 bc1nez and bc1eqz branches */
+ if (cpu_has_mips_r6 &&
+ ((insn.i_format.rs == bc1eqz_op) ||
+ (insn.i_format.rs == bc1nez_op))) {
+ bit = 0;
+ fpr = &current->thread.fpu.fpr[insn.i_format.rt];
+ bit0 = get_fpr32(fpr, 0) & 0x1;
+ switch (insn.i_format.rs) {
+ case bc1eqz_op:
+ bit = bit0 == 0;
+ break;
+ case bc1nez_op:
+ bit = bit0 != 0;
+ break;
+ }
+ if (bit)
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+
+ return 1;
+ }
+ /* R2/R6 compatible cop1 instruction */
+ /* fall through */
+ case cop2_op:
+ case cop1x_op:
+ if (insn.i_format.rs == bc_op) {
+ preempt_disable();
+ if (is_fpu_owner())
+ fcr31 = read_32bit_cp1_register(CP1_STATUS);
+ else
+ fcr31 = current->thread.fpu.fcr31;
+ preempt_enable();
+
+ bit = (insn.i_format.rt >> 2);
+ bit += (bit != 0);
+ bit += 23;
+ switch (insn.i_format.rt & 3) {
+ case 0: /* bc1f */
+ case 2: /* bc1fl */
+ if (~fcr31 & (1 << bit))
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ return 1;
+ case 1: /* bc1t */
+ case 3: /* bc1tl */
+ if (fcr31 & (1 << bit))
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ (insn.i_format.simmediate << 2);
+ else
+ *contpc = regs->cp0_epc +
+ dec_insn.pc_inc +
+ dec_insn.next_pc_inc;
+ return 1;
+ }
+ }
+ break;
+ }
+ return 0;
+}
+
+/*
+ * In the Linux kernel, we support selection of FPR format on the
+ * basis of the Status.FR bit. If an FPU is not present, the FR bit
+ * is hardwired to zero, which would imply a 32-bit FPU even for
+ * 64-bit CPUs so we rather look at TIF_32BIT_FPREGS.
+ * FPU emu is slow and bulky and optimizing this function offers fairly
+ * sizeable benefits so we try to be clever and make this function return
+ * a constant whenever possible, that is on 64-bit kernels without O32
+ * compatibility enabled and on 32-bit without 64-bit FPU support.
+ */
+static inline int cop1_64bit(struct pt_regs *xcp)
+{
+ if (IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_MIPS32_O32))
+ return 1;
+ else if (IS_ENABLED(CONFIG_32BIT) &&
+ !IS_ENABLED(CONFIG_MIPS_O32_FP64_SUPPORT))
+ return 0;
+
+ return !test_thread_flag(TIF_32BIT_FPREGS);
+}
+
+static inline bool hybrid_fprs(void)
+{
+ return test_thread_flag(TIF_HYBRID_FPREGS);
+}
+
+#define SIFROMREG(si, x) \
+do { \
+ if (cop1_64bit(xcp) && !hybrid_fprs()) \
+ (si) = (int)get_fpr32(&ctx->fpr[x], 0); \
+ else \
+ (si) = (int)get_fpr32(&ctx->fpr[(x) & ~1], (x) & 1); \
+} while (0)
+
+#define SITOREG(si, x) \
+do { \
+ if (cop1_64bit(xcp) && !hybrid_fprs()) { \
+ unsigned int i; \
+ set_fpr32(&ctx->fpr[x], 0, si); \
+ for (i = 1; i < ARRAY_SIZE(ctx->fpr[x].val32); i++) \
+ set_fpr32(&ctx->fpr[x], i, 0); \
+ } else { \
+ set_fpr32(&ctx->fpr[(x) & ~1], (x) & 1, si); \
+ } \
+} while (0)
+
+#define SIFROMHREG(si, x) ((si) = (int)get_fpr32(&ctx->fpr[x], 1))
+
+#define SITOHREG(si, x) \
+do { \
+ unsigned int i; \
+ set_fpr32(&ctx->fpr[x], 1, si); \
+ for (i = 2; i < ARRAY_SIZE(ctx->fpr[x].val32); i++) \
+ set_fpr32(&ctx->fpr[x], i, 0); \
+} while (0)
+
+#define DIFROMREG(di, x) \
+ ((di) = get_fpr64(&ctx->fpr[(x) & ~(cop1_64bit(xcp) ^ 1)], 0))
+
+#define DITOREG(di, x) \
+do { \
+ unsigned int fpr, i; \
+ fpr = (x) & ~(cop1_64bit(xcp) ^ 1); \
+ set_fpr64(&ctx->fpr[fpr], 0, di); \
+ for (i = 1; i < ARRAY_SIZE(ctx->fpr[x].val64); i++) \
+ set_fpr64(&ctx->fpr[fpr], i, 0); \
+} while (0)
+
+#define SPFROMREG(sp, x) SIFROMREG((sp).bits, x)
+#define SPTOREG(sp, x) SITOREG((sp).bits, x)
+#define DPFROMREG(dp, x) DIFROMREG((dp).bits, x)
+#define DPTOREG(dp, x) DITOREG((dp).bits, x)
+
+/*
+ * Emulate a CFC1 instruction.
+ */
+static inline void cop1_cfc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
+ mips_instruction ir)
+{
+ u32 fcr31 = ctx->fcr31;
+ u32 value = 0;
+
+ switch (MIPSInst_RD(ir)) {
+ case FPCREG_CSR:
+ value = fcr31;
+ pr_debug("%p gpr[%d]<-csr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ break;
+
+ case FPCREG_FENR:
+ if (!cpu_has_mips_r)
+ break;
+ value = (fcr31 >> (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
+ MIPS_FENR_FS;
+ value |= fcr31 & (FPU_CSR_ALL_E | FPU_CSR_RM);
+ pr_debug("%p gpr[%d]<-enr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ break;
+
+ case FPCREG_FEXR:
+ if (!cpu_has_mips_r)
+ break;
+ value = fcr31 & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
+ pr_debug("%p gpr[%d]<-exr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ break;
+
+ case FPCREG_FCCR:
+ if (!cpu_has_mips_r)
+ break;
+ value = (fcr31 >> (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
+ MIPS_FCCR_COND0;
+ value |= (fcr31 >> (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
+ (MIPS_FCCR_CONDX & ~MIPS_FCCR_COND0);
+ pr_debug("%p gpr[%d]<-ccr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ break;
+
+ case FPCREG_RID:
+ value = boot_cpu_data.fpu_id;
+ break;
+
+ default:
+ break;
+ }
+
+ if (MIPSInst_RT(ir))
+ xcp->regs[MIPSInst_RT(ir)] = value;
+}
+
+/*
+ * Emulate a CTC1 instruction.
+ */
+static inline void cop1_ctc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
+ mips_instruction ir)
+{
+ u32 fcr31 = ctx->fcr31;
+ u32 value;
+ u32 mask;
+
+ if (MIPSInst_RT(ir) == 0)
+ value = 0;
+ else
+ value = xcp->regs[MIPSInst_RT(ir)];
+
+ switch (MIPSInst_RD(ir)) {
+ case FPCREG_CSR:
+ pr_debug("%p gpr[%d]->csr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+
+ /* Preserve read-only bits. */
+ mask = boot_cpu_data.fpu_msk31;
+ fcr31 = (value & ~mask) | (fcr31 & mask);
+ break;
+
+ case FPCREG_FENR:
+ if (!cpu_has_mips_r)
+ break;
+ pr_debug("%p gpr[%d]->enr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ fcr31 &= ~(FPU_CSR_FS | FPU_CSR_ALL_E | FPU_CSR_RM);
+ fcr31 |= (value << (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
+ FPU_CSR_FS;
+ fcr31 |= value & (FPU_CSR_ALL_E | FPU_CSR_RM);
+ break;
+
+ case FPCREG_FEXR:
+ if (!cpu_has_mips_r)
+ break;
+ pr_debug("%p gpr[%d]->exr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ fcr31 &= ~(FPU_CSR_ALL_X | FPU_CSR_ALL_S);
+ fcr31 |= value & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
+ break;
+
+ case FPCREG_FCCR:
+ if (!cpu_has_mips_r)
+ break;
+ pr_debug("%p gpr[%d]->ccr=%08x\n",
+ (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
+ fcr31 &= ~(FPU_CSR_CONDX | FPU_CSR_COND);
+ fcr31 |= (value << (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
+ FPU_CSR_COND;
+ fcr31 |= (value << (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
+ FPU_CSR_CONDX;
+ break;
+
+ default:
+ break;
+ }
+
+ ctx->fcr31 = fcr31;
+}
+
+/*
+ * Emulate the single floating point instruction pointed at by EPC.
+ * Two instructions if the instruction is in a branch delay slot.
+ */
+
+static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
+ struct mm_decoded_insn dec_insn, void __user **fault_addr)
+{
+ unsigned long contpc = xcp->cp0_epc + dec_insn.pc_inc;
+ unsigned int cond, cbit, bit0;
+ mips_instruction ir;
+ int likely, pc_inc;
+ union fpureg *fpr;
+ u32 __user *wva;
+ u64 __user *dva;
+ u32 wval;
+ u64 dval;
+ int sig;
+
+ /*
+ * These are giving gcc a gentle hint about what to expect in
+ * dec_inst in order to do better optimization.
+ */
+ if (!cpu_has_mmips && dec_insn.micro_mips_mode)
+ unreachable();
+
+ /* XXX NEC Vr54xx bug workaround */
+ if (delay_slot(xcp)) {
+ if (dec_insn.micro_mips_mode) {
+ if (!mm_isBranchInstr(xcp, dec_insn, &contpc))
+ clear_delay_slot(xcp);
+ } else {
+ if (!isBranchInstr(xcp, dec_insn, &contpc))
+ clear_delay_slot(xcp);
+ }
+ }
+
+ if (delay_slot(xcp)) {
+ /*
+ * The instruction to be emulated is in a branch delay slot
+ * which means that we have to emulate the branch instruction
+ * BEFORE we do the cop1 instruction.
+ *
+ * This branch could be a COP1 branch, but in that case we
+ * would have had a trap for that instruction, and would not
+ * come through this route.
+ *
+ * Linux MIPS branch emulator operates on context, updating the
+ * cp0_epc.
+ */
+ ir = dec_insn.next_insn; /* process delay slot instr */
+ pc_inc = dec_insn.next_pc_inc;
+ } else {
+ ir = dec_insn.insn; /* process current instr */
+ pc_inc = dec_insn.pc_inc;
+ }
+
+ /*
+ * Since microMIPS FPU instructios are a subset of MIPS32 FPU
+ * instructions, we want to convert microMIPS FPU instructions
+ * into MIPS32 instructions so that we could reuse all of the
+ * FPU emulation code.
+ *
+ * NOTE: We cannot do this for branch instructions since they
+ * are not a subset. Example: Cannot emulate a 16-bit
+ * aligned target address with a MIPS32 instruction.
+ */
+ if (dec_insn.micro_mips_mode) {
+ /*
+ * If next instruction is a 16-bit instruction, then it
+ * it cannot be a FPU instruction. This could happen
+ * since we can be called for non-FPU instructions.
+ */
+ if ((pc_inc == 2) ||
+ (microMIPS32_to_MIPS32((union mips_instruction *)&ir)
+ == SIGILL))
+ return SIGILL;
+ }
+
+emul:
+ perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, xcp, 0);
+ MIPS_FPU_EMU_INC_STATS(emulated);
+ switch (MIPSInst_OPCODE(ir)) {
+ case ldc1_op:
+ dva = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
+ MIPSInst_SIMM(ir));
+ MIPS_FPU_EMU_INC_STATS(loads);
+
+ if (!access_ok(VERIFY_READ, dva, sizeof(u64))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = dva;
+ return SIGBUS;
+ }
+ if (__get_user(dval, dva)) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = dva;
+ return SIGSEGV;
+ }
+ DITOREG(dval, MIPSInst_RT(ir));
+ break;
+
+ case sdc1_op:
+ dva = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
+ MIPSInst_SIMM(ir));
+ MIPS_FPU_EMU_INC_STATS(stores);
+ DIFROMREG(dval, MIPSInst_RT(ir));
+ if (!access_ok(VERIFY_WRITE, dva, sizeof(u64))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = dva;
+ return SIGBUS;
+ }
+ if (__put_user(dval, dva)) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = dva;
+ return SIGSEGV;
+ }
+ break;
+
+ case lwc1_op:
+ wva = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
+ MIPSInst_SIMM(ir));
+ MIPS_FPU_EMU_INC_STATS(loads);
+ if (!access_ok(VERIFY_READ, wva, sizeof(u32))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = wva;
+ return SIGBUS;
+ }
+ if (__get_user(wval, wva)) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = wva;
+ return SIGSEGV;
+ }
+ SITOREG(wval, MIPSInst_RT(ir));
+ break;
+
+ case swc1_op:
+ wva = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
+ MIPSInst_SIMM(ir));
+ MIPS_FPU_EMU_INC_STATS(stores);
+ SIFROMREG(wval, MIPSInst_RT(ir));
+ if (!access_ok(VERIFY_WRITE, wva, sizeof(u32))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = wva;
+ return SIGBUS;
+ }
+ if (__put_user(wval, wva)) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = wva;
+ return SIGSEGV;
+ }
+ break;
+
+ case cop1_op:
+ switch (MIPSInst_RS(ir)) {
+ case dmfc_op:
+ if (!cpu_has_mips_3_4_5 && !cpu_has_mips64)
+ return SIGILL;
+
+ /* copregister fs -> gpr[rt] */
+ if (MIPSInst_RT(ir) != 0) {
+ DIFROMREG(xcp->regs[MIPSInst_RT(ir)],
+ MIPSInst_RD(ir));
+ }
+ break;
+
+ case dmtc_op:
+ if (!cpu_has_mips_3_4_5 && !cpu_has_mips64)
+ return SIGILL;
+
+ /* copregister fs <- rt */
+ DITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
+ break;
+
+ case mfhc_op:
+ if (!cpu_has_mips_r2_r6)
+ return SIGILL;
+
+ /* copregister rd -> gpr[rt] */
+ if (MIPSInst_RT(ir) != 0) {
+ SIFROMHREG(xcp->regs[MIPSInst_RT(ir)],
+ MIPSInst_RD(ir));
+ }
+ break;
+
+ case mthc_op:
+ if (!cpu_has_mips_r2_r6)
+ return SIGILL;
+
+ /* copregister rd <- gpr[rt] */
+ SITOHREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
+ break;
+
+ case mfc_op:
+ /* copregister rd -> gpr[rt] */
+ if (MIPSInst_RT(ir) != 0) {
+ SIFROMREG(xcp->regs[MIPSInst_RT(ir)],
+ MIPSInst_RD(ir));
+ }
+ break;
+
+ case mtc_op:
+ /* copregister rd <- rt */
+ SITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
+ break;
+
+ case cfc_op:
+ /* cop control register rd -> gpr[rt] */
+ cop1_cfc(xcp, ctx, ir);
+ break;
+
+ case ctc_op:
+ /* copregister rd <- rt */
+ cop1_ctc(xcp, ctx, ir);
+ if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
+ return SIGFPE;
+ }
+ break;
+
+ case bc1eqz_op:
+ case bc1nez_op:
+ if (!cpu_has_mips_r6 || delay_slot(xcp))
+ return SIGILL;
+
+ likely = 0;
+ cond = 0;
+ fpr = &current->thread.fpu.fpr[MIPSInst_RT(ir)];
+ bit0 = get_fpr32(fpr, 0) & 0x1;
+ switch (MIPSInst_RS(ir)) {
+ case bc1eqz_op:
+ MIPS_FPU_EMU_INC_STATS(bc1eqz);
+ cond = bit0 == 0;
+ break;
+ case bc1nez_op:
+ MIPS_FPU_EMU_INC_STATS(bc1nez);
+ cond = bit0 != 0;
+ break;
+ }
+ goto branch_common;
+
+ case bc_op:
+ if (delay_slot(xcp))
+ return SIGILL;
+
+ if (cpu_has_mips_4_5_r)
+ cbit = fpucondbit[MIPSInst_RT(ir) >> 2];
+ else
+ cbit = FPU_CSR_COND;
+ cond = ctx->fcr31 & cbit;
+
+ likely = 0;
+ switch (MIPSInst_RT(ir) & 3) {
+ case bcfl_op:
+ if (cpu_has_mips_2_3_4_5_r)
+ likely = 1;
+ /* fall through */
+ case bcf_op:
+ cond = !cond;
+ break;
+ case bctl_op:
+ if (cpu_has_mips_2_3_4_5_r)
+ likely = 1;
+ /* fall through */
+ case bct_op:
+ break;
+ }
+branch_common:
+ MIPS_FPU_EMU_INC_STATS(branches);
+ set_delay_slot(xcp);
+ if (cond) {
+ /*
+ * Branch taken: emulate dslot instruction
+ */
+ unsigned long bcpc;
+
+ /*
+ * Remember EPC at the branch to point back
+ * at so that any delay-slot instruction
+ * signal is not silently ignored.
+ */
+ bcpc = xcp->cp0_epc;
+ xcp->cp0_epc += dec_insn.pc_inc;
+
+ contpc = MIPSInst_SIMM(ir);
+ ir = dec_insn.next_insn;
+ if (dec_insn.micro_mips_mode) {
+ contpc = (xcp->cp0_epc + (contpc << 1));
+
+ /* If 16-bit instruction, not FPU. */
+ if ((dec_insn.next_pc_inc == 2) ||
+ (microMIPS32_to_MIPS32((union mips_instruction *)&ir) == SIGILL)) {
+
+ /*
+ * Since this instruction will
+ * be put on the stack with
+ * 32-bit words, get around
+ * this problem by putting a
+ * NOP16 as the second one.
+ */
+ if (dec_insn.next_pc_inc == 2)
+ ir = (ir & (~0xffff)) | MM_NOP16;
+
+ /*
+ * Single step the non-CP1
+ * instruction in the dslot.
+ */
+ sig = mips_dsemul(xcp, ir,
+ bcpc, contpc);
+ if (sig < 0)
+ break;
+ if (sig)
+ xcp->cp0_epc = bcpc;
+ /*
+ * SIGILL forces out of
+ * the emulation loop.
+ */
+ return sig ? sig : SIGILL;
+ }
+ } else
+ contpc = (xcp->cp0_epc + (contpc << 2));
+
+ switch (MIPSInst_OPCODE(ir)) {
+ case lwc1_op:
+ case swc1_op:
+ goto emul;
+
+ case ldc1_op:
+ case sdc1_op:
+ if (cpu_has_mips_2_3_4_5_r)
+ goto emul;
+
+ goto bc_sigill;
+
+ case cop1_op:
+ goto emul;
+
+ case cop1x_op:
+ if (cpu_has_mips_4_5_64_r2_r6)
+ /* its one of ours */
+ goto emul;
+
+ goto bc_sigill;
+
+ case spec_op:
+ switch (MIPSInst_FUNC(ir)) {
+ case movc_op:
+ if (cpu_has_mips_4_5_r)
+ goto emul;
+
+ goto bc_sigill;
+ }
+ break;
+
+ bc_sigill:
+ xcp->cp0_epc = bcpc;
+ return SIGILL;
+ }
+
+ /*
+ * Single step the non-cp1
+ * instruction in the dslot
+ */
+ sig = mips_dsemul(xcp, ir, bcpc, contpc);
+ if (sig < 0)
+ break;
+ if (sig)
+ xcp->cp0_epc = bcpc;
+ /* SIGILL forces out of the emulation loop. */
+ return sig ? sig : SIGILL;
+ } else if (likely) { /* branch not taken */
+ /*
+ * branch likely nullifies
+ * dslot if not taken
+ */
+ xcp->cp0_epc += dec_insn.pc_inc;
+ contpc += dec_insn.pc_inc;
+ /*
+ * else continue & execute
+ * dslot as normal insn
+ */
+ }
+ break;
+
+ default:
+ if (!(MIPSInst_RS(ir) & 0x10))
+ return SIGILL;
+
+ /* a real fpu computation instruction */
+ sig = fpu_emu(xcp, ctx, ir);
+ if (sig)
+ return sig;
+ }
+ break;
+
+ case cop1x_op:
+ if (!cpu_has_mips_4_5_64_r2_r6)
+ return SIGILL;
+
+ sig = fpux_emu(xcp, ctx, ir, fault_addr);
+ if (sig)
+ return sig;
+ break;
+
+ case spec_op:
+ if (!cpu_has_mips_4_5_r)
+ return SIGILL;
+
+ if (MIPSInst_FUNC(ir) != movc_op)
+ return SIGILL;
+ cond = fpucondbit[MIPSInst_RT(ir) >> 2];
+ if (((ctx->fcr31 & cond) != 0) == ((MIPSInst_RT(ir) & 1) != 0))
+ xcp->regs[MIPSInst_RD(ir)] =
+ xcp->regs[MIPSInst_RS(ir)];
+ break;
+ default:
+ return SIGILL;
+ }
+
+ /* we did it !! */
+ xcp->cp0_epc = contpc;
+ clear_delay_slot(xcp);
+
+ return 0;
+}
+
+/*
+ * Conversion table from MIPS compare ops 48-63
+ * cond = ieee754dp_cmp(x,y,IEEE754_UN,sig);
+ */
+static const unsigned char cmptab[8] = {
+ 0, /* cmp_0 (sig) cmp_sf */
+ IEEE754_CUN, /* cmp_un (sig) cmp_ngle */
+ IEEE754_CEQ, /* cmp_eq (sig) cmp_seq */
+ IEEE754_CEQ | IEEE754_CUN, /* cmp_ueq (sig) cmp_ngl */
+ IEEE754_CLT, /* cmp_olt (sig) cmp_lt */
+ IEEE754_CLT | IEEE754_CUN, /* cmp_ult (sig) cmp_nge */
+ IEEE754_CLT | IEEE754_CEQ, /* cmp_ole (sig) cmp_le */
+ IEEE754_CLT | IEEE754_CEQ | IEEE754_CUN, /* cmp_ule (sig) cmp_ngt */
+};
+
+static const unsigned char negative_cmptab[8] = {
+ 0, /* Reserved */
+ IEEE754_CLT | IEEE754_CGT | IEEE754_CEQ,
+ IEEE754_CLT | IEEE754_CGT | IEEE754_CUN,
+ IEEE754_CLT | IEEE754_CGT,
+ /* Reserved */
+};
+
+
+/*
+ * Additional MIPS4 instructions
+ */
+
+#define DEF3OP(name, p, f1, f2, f3) \
+static union ieee754##p fpemu_##p##_##name(union ieee754##p r, \
+ union ieee754##p s, union ieee754##p t) \
+{ \
+ struct _ieee754_csr ieee754_csr_save; \
+ s = f1(s, t); \
+ ieee754_csr_save = ieee754_csr; \
+ s = f2(s, r); \
+ ieee754_csr_save.cx |= ieee754_csr.cx; \
+ ieee754_csr_save.sx |= ieee754_csr.sx; \
+ s = f3(s); \
+ ieee754_csr.cx |= ieee754_csr_save.cx; \
+ ieee754_csr.sx |= ieee754_csr_save.sx; \
+ return s; \
+}
+
+static union ieee754dp fpemu_dp_recip(union ieee754dp d)
+{
+ return ieee754dp_div(ieee754dp_one(0), d);
+}
+
+static union ieee754dp fpemu_dp_rsqrt(union ieee754dp d)
+{
+ return ieee754dp_div(ieee754dp_one(0), ieee754dp_sqrt(d));
+}
+
+static union ieee754sp fpemu_sp_recip(union ieee754sp s)
+{
+ return ieee754sp_div(ieee754sp_one(0), s);
+}
+
+static union ieee754sp fpemu_sp_rsqrt(union ieee754sp s)
+{
+ return ieee754sp_div(ieee754sp_one(0), ieee754sp_sqrt(s));
+}
+
+DEF3OP(madd, sp, ieee754sp_mul, ieee754sp_add, );
+DEF3OP(msub, sp, ieee754sp_mul, ieee754sp_sub, );
+DEF3OP(nmadd, sp, ieee754sp_mul, ieee754sp_add, ieee754sp_neg);
+DEF3OP(nmsub, sp, ieee754sp_mul, ieee754sp_sub, ieee754sp_neg);
+DEF3OP(madd, dp, ieee754dp_mul, ieee754dp_add, );
+DEF3OP(msub, dp, ieee754dp_mul, ieee754dp_sub, );
+DEF3OP(nmadd, dp, ieee754dp_mul, ieee754dp_add, ieee754dp_neg);
+DEF3OP(nmsub, dp, ieee754dp_mul, ieee754dp_sub, ieee754dp_neg);
+
+static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
+ mips_instruction ir, void __user **fault_addr)
+{
+ unsigned int rcsr = 0; /* resulting csr */
+
+ MIPS_FPU_EMU_INC_STATS(cp1xops);
+
+ switch (MIPSInst_FMA_FFMT(ir)) {
+ case s_fmt:{ /* 0 */
+
+ union ieee754sp(*handler) (union ieee754sp, union ieee754sp, union ieee754sp);
+ union ieee754sp fd, fr, fs, ft;
+ u32 __user *va;
+ u32 val;
+
+ switch (MIPSInst_FUNC(ir)) {
+ case lwxc1_op:
+ va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
+ xcp->regs[MIPSInst_FT(ir)]);
+
+ MIPS_FPU_EMU_INC_STATS(loads);
+ if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = va;
+ return SIGBUS;
+ }
+ if (__get_user(val, va)) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = va;
+ return SIGSEGV;
+ }
+ SITOREG(val, MIPSInst_FD(ir));
+ break;
+
+ case swxc1_op:
+ va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
+ xcp->regs[MIPSInst_FT(ir)]);
+
+ MIPS_FPU_EMU_INC_STATS(stores);
+
+ SIFROMREG(val, MIPSInst_FS(ir));
+ if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = va;
+ return SIGBUS;
+ }
+ if (put_user(val, va)) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = va;
+ return SIGSEGV;
+ }
+ break;
+
+ case madd_s_op:
+ handler = fpemu_sp_madd;
+ goto scoptop;
+ case msub_s_op:
+ handler = fpemu_sp_msub;
+ goto scoptop;
+ case nmadd_s_op:
+ handler = fpemu_sp_nmadd;
+ goto scoptop;
+ case nmsub_s_op:
+ handler = fpemu_sp_nmsub;
+ goto scoptop;
+
+ scoptop:
+ SPFROMREG(fr, MIPSInst_FR(ir));
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ SPFROMREG(ft, MIPSInst_FT(ir));
+ fd = (*handler) (fr, fs, ft);
+ SPTOREG(fd, MIPSInst_FD(ir));
+
+ copcsr:
+ if (ieee754_cxtest(IEEE754_INEXACT)) {
+ MIPS_FPU_EMU_INC_STATS(ieee754_inexact);
+ rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
+ }
+ if (ieee754_cxtest(IEEE754_UNDERFLOW)) {
+ MIPS_FPU_EMU_INC_STATS(ieee754_underflow);
+ rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
+ }
+ if (ieee754_cxtest(IEEE754_OVERFLOW)) {
+ MIPS_FPU_EMU_INC_STATS(ieee754_overflow);
+ rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
+ }
+ if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) {
+ MIPS_FPU_EMU_INC_STATS(ieee754_invalidop);
+ rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
+ }
+
+ ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
+ if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
+ /*printk ("SIGFPE: FPU csr = %08x\n",
+ ctx->fcr31); */
+ return SIGFPE;
+ }
+
+ break;
+
+ default:
+ return SIGILL;
+ }
+ break;
+ }
+
+ case d_fmt:{ /* 1 */
+ union ieee754dp(*handler) (union ieee754dp, union ieee754dp, union ieee754dp);
+ union ieee754dp fd, fr, fs, ft;
+ u64 __user *va;
+ u64 val;
+
+ switch (MIPSInst_FUNC(ir)) {
+ case ldxc1_op:
+ va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
+ xcp->regs[MIPSInst_FT(ir)]);
+
+ MIPS_FPU_EMU_INC_STATS(loads);
+ if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = va;
+ return SIGBUS;
+ }
+ if (__get_user(val, va)) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = va;
+ return SIGSEGV;
+ }
+ DITOREG(val, MIPSInst_FD(ir));
+ break;
+
+ case sdxc1_op:
+ va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
+ xcp->regs[MIPSInst_FT(ir)]);
+
+ MIPS_FPU_EMU_INC_STATS(stores);
+ DIFROMREG(val, MIPSInst_FS(ir));
+ if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = va;
+ return SIGBUS;
+ }
+ if (__put_user(val, va)) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ *fault_addr = va;
+ return SIGSEGV;
+ }
+ break;
+
+ case madd_d_op:
+ handler = fpemu_dp_madd;
+ goto dcoptop;
+ case msub_d_op:
+ handler = fpemu_dp_msub;
+ goto dcoptop;
+ case nmadd_d_op:
+ handler = fpemu_dp_nmadd;
+ goto dcoptop;
+ case nmsub_d_op:
+ handler = fpemu_dp_nmsub;
+ goto dcoptop;
+
+ dcoptop:
+ DPFROMREG(fr, MIPSInst_FR(ir));
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ DPFROMREG(ft, MIPSInst_FT(ir));
+ fd = (*handler) (fr, fs, ft);
+ DPTOREG(fd, MIPSInst_FD(ir));
+ goto copcsr;
+
+ default:
+ return SIGILL;
+ }
+ break;
+ }
+
+ case 0x3:
+ if (MIPSInst_FUNC(ir) != pfetch_op)
+ return SIGILL;
+
+ /* ignore prefx operation */
+ break;
+
+ default:
+ return SIGILL;
+ }
+
+ return 0;
+}
+
+
+
+/*
+ * Emulate a single COP1 arithmetic instruction.
+ */
+static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
+ mips_instruction ir)
+{
+ int rfmt; /* resulting format */
+ unsigned int rcsr = 0; /* resulting csr */
+ unsigned int oldrm;
+ unsigned int cbit;
+ unsigned int cond;
+ union {
+ union ieee754dp d;
+ union ieee754sp s;
+ int w;
+ s64 l;
+ } rv; /* resulting value */
+ u64 bits;
+
+ MIPS_FPU_EMU_INC_STATS(cp1ops);
+ switch (rfmt = (MIPSInst_FFMT(ir) & 0xf)) {
+ case s_fmt: { /* 0 */
+ union {
+ union ieee754sp(*b) (union ieee754sp, union ieee754sp);
+ union ieee754sp(*u) (union ieee754sp);
+ } handler;
+ union ieee754sp fd, fs, ft;
+
+ switch (MIPSInst_FUNC(ir)) {
+ /* binary ops */
+ case fadd_op:
+ MIPS_FPU_EMU_INC_STATS(add_s);
+ handler.b = ieee754sp_add;
+ goto scopbop;
+ case fsub_op:
+ MIPS_FPU_EMU_INC_STATS(sub_s);
+ handler.b = ieee754sp_sub;
+ goto scopbop;
+ case fmul_op:
+ MIPS_FPU_EMU_INC_STATS(mul_s);
+ handler.b = ieee754sp_mul;
+ goto scopbop;
+ case fdiv_op:
+ MIPS_FPU_EMU_INC_STATS(div_s);
+ handler.b = ieee754sp_div;
+ goto scopbop;
+
+ /* unary ops */
+ case fsqrt_op:
+ if (!cpu_has_mips_2_3_4_5_r)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(sqrt_s);
+ handler.u = ieee754sp_sqrt;
+ goto scopuop;
+
+ /*
+ * Note that on some MIPS IV implementations such as the
+ * R5000 and R8000 the FSQRT and FRECIP instructions do not
+ * achieve full IEEE-754 accuracy - however this emulator does.
+ */
+ case frsqrt_op:
+ if (!cpu_has_mips_4_5_64_r2_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(rsqrt_s);
+ handler.u = fpemu_sp_rsqrt;
+ goto scopuop;
+
+ case frecip_op:
+ if (!cpu_has_mips_4_5_64_r2_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(recip_s);
+ handler.u = fpemu_sp_recip;
+ goto scopuop;
+
+ case fmovc_op:
+ if (!cpu_has_mips_4_5_r)
+ return SIGILL;
+
+ cond = fpucondbit[MIPSInst_FT(ir) >> 2];
+ if (((ctx->fcr31 & cond) != 0) !=
+ ((MIPSInst_FT(ir) & 1) != 0))
+ return 0;
+ SPFROMREG(rv.s, MIPSInst_FS(ir));
+ break;
+
+ case fmovz_op:
+ if (!cpu_has_mips_4_5_r)
+ return SIGILL;
+
+ if (xcp->regs[MIPSInst_FT(ir)] != 0)
+ return 0;
+ SPFROMREG(rv.s, MIPSInst_FS(ir));
+ break;
+
+ case fmovn_op:
+ if (!cpu_has_mips_4_5_r)
+ return SIGILL;
+
+ if (xcp->regs[MIPSInst_FT(ir)] == 0)
+ return 0;
+ SPFROMREG(rv.s, MIPSInst_FS(ir));
+ break;
+
+ case fseleqz_op:
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(seleqz_s);
+ SPFROMREG(rv.s, MIPSInst_FT(ir));
+ if (rv.w & 0x1)
+ rv.w = 0;
+ else
+ SPFROMREG(rv.s, MIPSInst_FS(ir));
+ break;
+
+ case fselnez_op:
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(selnez_s);
+ SPFROMREG(rv.s, MIPSInst_FT(ir));
+ if (rv.w & 0x1)
+ SPFROMREG(rv.s, MIPSInst_FS(ir));
+ else
+ rv.w = 0;
+ break;
+
+ case fmaddf_op: {
+ union ieee754sp ft, fs, fd;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(maddf_s);
+ SPFROMREG(ft, MIPSInst_FT(ir));
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ SPFROMREG(fd, MIPSInst_FD(ir));
+ rv.s = ieee754sp_maddf(fd, fs, ft);
+ goto copcsr;
+ }
+
+ case fmsubf_op: {
+ union ieee754sp ft, fs, fd;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(msubf_s);
+ SPFROMREG(ft, MIPSInst_FT(ir));
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ SPFROMREG(fd, MIPSInst_FD(ir));
+ rv.s = ieee754sp_msubf(fd, fs, ft);
+ goto copcsr;
+ }
+
+ case frint_op: {
+ union ieee754sp fs;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(rint_s);
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.s = ieee754sp_rint(fs);
+ goto copcsr;
+ }
+
+ case fclass_op: {
+ union ieee754sp fs;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(class_s);
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.w = ieee754sp_2008class(fs);
+ rfmt = w_fmt;
+ goto copcsr;
+ }
+
+ case fmin_op: {
+ union ieee754sp fs, ft;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(min_s);
+ SPFROMREG(ft, MIPSInst_FT(ir));
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.s = ieee754sp_fmin(fs, ft);
+ goto copcsr;
+ }
+
+ case fmina_op: {
+ union ieee754sp fs, ft;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(mina_s);
+ SPFROMREG(ft, MIPSInst_FT(ir));
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.s = ieee754sp_fmina(fs, ft);
+ goto copcsr;
+ }
+
+ case fmax_op: {
+ union ieee754sp fs, ft;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(max_s);
+ SPFROMREG(ft, MIPSInst_FT(ir));
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.s = ieee754sp_fmax(fs, ft);
+ goto copcsr;
+ }
+
+ case fmaxa_op: {
+ union ieee754sp fs, ft;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(maxa_s);
+ SPFROMREG(ft, MIPSInst_FT(ir));
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.s = ieee754sp_fmaxa(fs, ft);
+ goto copcsr;
+ }
+
+ case fabs_op:
+ MIPS_FPU_EMU_INC_STATS(abs_s);
+ handler.u = ieee754sp_abs;
+ goto scopuop;
+
+ case fneg_op:
+ MIPS_FPU_EMU_INC_STATS(neg_s);
+ handler.u = ieee754sp_neg;
+ goto scopuop;
+
+ case fmov_op:
+ /* an easy one */
+ MIPS_FPU_EMU_INC_STATS(mov_s);
+ SPFROMREG(rv.s, MIPSInst_FS(ir));
+ goto copcsr;
+
+ /* binary op on handler */
+scopbop:
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ SPFROMREG(ft, MIPSInst_FT(ir));
+
+ rv.s = (*handler.b) (fs, ft);
+ goto copcsr;
+scopuop:
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.s = (*handler.u) (fs);
+ goto copcsr;
+copcsr:
+ if (ieee754_cxtest(IEEE754_INEXACT)) {
+ MIPS_FPU_EMU_INC_STATS(ieee754_inexact);
+ rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
+ }
+ if (ieee754_cxtest(IEEE754_UNDERFLOW)) {
+ MIPS_FPU_EMU_INC_STATS(ieee754_underflow);
+ rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
+ }
+ if (ieee754_cxtest(IEEE754_OVERFLOW)) {
+ MIPS_FPU_EMU_INC_STATS(ieee754_overflow);
+ rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
+ }
+ if (ieee754_cxtest(IEEE754_ZERO_DIVIDE)) {
+ MIPS_FPU_EMU_INC_STATS(ieee754_zerodiv);
+ rcsr |= FPU_CSR_DIV_X | FPU_CSR_DIV_S;
+ }
+ if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) {
+ MIPS_FPU_EMU_INC_STATS(ieee754_invalidop);
+ rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
+ }
+ break;
+
+ /* unary conv ops */
+ case fcvts_op:
+ return SIGILL; /* not defined */
+
+ case fcvtd_op:
+ MIPS_FPU_EMU_INC_STATS(cvt_d_s);
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.d = ieee754dp_fsp(fs);
+ rfmt = d_fmt;
+ goto copcsr;
+
+ case fcvtw_op:
+ MIPS_FPU_EMU_INC_STATS(cvt_w_s);
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.w = ieee754sp_tint(fs);
+ rfmt = w_fmt;
+ goto copcsr;
+
+ case fround_op:
+ case ftrunc_op:
+ case fceil_op:
+ case ffloor_op:
+ if (!cpu_has_mips_2_3_4_5_r)
+ return SIGILL;
+
+ if (MIPSInst_FUNC(ir) == fceil_op)
+ MIPS_FPU_EMU_INC_STATS(ceil_w_s);
+ if (MIPSInst_FUNC(ir) == ffloor_op)
+ MIPS_FPU_EMU_INC_STATS(floor_w_s);
+ if (MIPSInst_FUNC(ir) == fround_op)
+ MIPS_FPU_EMU_INC_STATS(round_w_s);
+ if (MIPSInst_FUNC(ir) == ftrunc_op)
+ MIPS_FPU_EMU_INC_STATS(trunc_w_s);
+
+ oldrm = ieee754_csr.rm;
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ ieee754_csr.rm = MIPSInst_FUNC(ir);
+ rv.w = ieee754sp_tint(fs);
+ ieee754_csr.rm = oldrm;
+ rfmt = w_fmt;
+ goto copcsr;
+
+ case fsel_op:
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(sel_s);
+ SPFROMREG(fd, MIPSInst_FD(ir));
+ if (fd.bits & 0x1)
+ SPFROMREG(rv.s, MIPSInst_FT(ir));
+ else
+ SPFROMREG(rv.s, MIPSInst_FS(ir));
+ break;
+
+ case fcvtl_op:
+ if (!cpu_has_mips_3_4_5_64_r2_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(cvt_l_s);
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.l = ieee754sp_tlong(fs);
+ rfmt = l_fmt;
+ goto copcsr;
+
+ case froundl_op:
+ case ftruncl_op:
+ case fceill_op:
+ case ffloorl_op:
+ if (!cpu_has_mips_3_4_5_64_r2_r6)
+ return SIGILL;
+
+ if (MIPSInst_FUNC(ir) == fceill_op)
+ MIPS_FPU_EMU_INC_STATS(ceil_l_s);
+ if (MIPSInst_FUNC(ir) == ffloorl_op)
+ MIPS_FPU_EMU_INC_STATS(floor_l_s);
+ if (MIPSInst_FUNC(ir) == froundl_op)
+ MIPS_FPU_EMU_INC_STATS(round_l_s);
+ if (MIPSInst_FUNC(ir) == ftruncl_op)
+ MIPS_FPU_EMU_INC_STATS(trunc_l_s);
+
+ oldrm = ieee754_csr.rm;
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ ieee754_csr.rm = MIPSInst_FUNC(ir);
+ rv.l = ieee754sp_tlong(fs);
+ ieee754_csr.rm = oldrm;
+ rfmt = l_fmt;
+ goto copcsr;
+
+ default:
+ if (!NO_R6EMU && MIPSInst_FUNC(ir) >= fcmp_op) {
+ unsigned int cmpop;
+ union ieee754sp fs, ft;
+
+ cmpop = MIPSInst_FUNC(ir) - fcmp_op;
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ SPFROMREG(ft, MIPSInst_FT(ir));
+ rv.w = ieee754sp_cmp(fs, ft,
+ cmptab[cmpop & 0x7], cmpop & 0x8);
+ rfmt = -1;
+ if ((cmpop & 0x8) && ieee754_cxtest
+ (IEEE754_INVALID_OPERATION))
+ rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
+ else
+ goto copcsr;
+
+ } else
+ return SIGILL;
+ break;
+ }
+ break;
+ }
+
+ case d_fmt: {
+ union ieee754dp fd, fs, ft;
+ union {
+ union ieee754dp(*b) (union ieee754dp, union ieee754dp);
+ union ieee754dp(*u) (union ieee754dp);
+ } handler;
+
+ switch (MIPSInst_FUNC(ir)) {
+ /* binary ops */
+ case fadd_op:
+ MIPS_FPU_EMU_INC_STATS(add_d);
+ handler.b = ieee754dp_add;
+ goto dcopbop;
+ case fsub_op:
+ MIPS_FPU_EMU_INC_STATS(sub_d);
+ handler.b = ieee754dp_sub;
+ goto dcopbop;
+ case fmul_op:
+ MIPS_FPU_EMU_INC_STATS(mul_d);
+ handler.b = ieee754dp_mul;
+ goto dcopbop;
+ case fdiv_op:
+ MIPS_FPU_EMU_INC_STATS(div_d);
+ handler.b = ieee754dp_div;
+ goto dcopbop;
+
+ /* unary ops */
+ case fsqrt_op:
+ if (!cpu_has_mips_2_3_4_5_r)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(sqrt_d);
+ handler.u = ieee754dp_sqrt;
+ goto dcopuop;
+ /*
+ * Note that on some MIPS IV implementations such as the
+ * R5000 and R8000 the FSQRT and FRECIP instructions do not
+ * achieve full IEEE-754 accuracy - however this emulator does.
+ */
+ case frsqrt_op:
+ if (!cpu_has_mips_4_5_64_r2_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(rsqrt_d);
+ handler.u = fpemu_dp_rsqrt;
+ goto dcopuop;
+ case frecip_op:
+ if (!cpu_has_mips_4_5_64_r2_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(recip_d);
+ handler.u = fpemu_dp_recip;
+ goto dcopuop;
+ case fmovc_op:
+ if (!cpu_has_mips_4_5_r)
+ return SIGILL;
+
+ cond = fpucondbit[MIPSInst_FT(ir) >> 2];
+ if (((ctx->fcr31 & cond) != 0) !=
+ ((MIPSInst_FT(ir) & 1) != 0))
+ return 0;
+ DPFROMREG(rv.d, MIPSInst_FS(ir));
+ break;
+ case fmovz_op:
+ if (!cpu_has_mips_4_5_r)
+ return SIGILL;
+
+ if (xcp->regs[MIPSInst_FT(ir)] != 0)
+ return 0;
+ DPFROMREG(rv.d, MIPSInst_FS(ir));
+ break;
+ case fmovn_op:
+ if (!cpu_has_mips_4_5_r)
+ return SIGILL;
+
+ if (xcp->regs[MIPSInst_FT(ir)] == 0)
+ return 0;
+ DPFROMREG(rv.d, MIPSInst_FS(ir));
+ break;
+
+ case fseleqz_op:
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(seleqz_d);
+ DPFROMREG(rv.d, MIPSInst_FT(ir));
+ if (rv.l & 0x1)
+ rv.l = 0;
+ else
+ DPFROMREG(rv.d, MIPSInst_FS(ir));
+ break;
+
+ case fselnez_op:
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(selnez_d);
+ DPFROMREG(rv.d, MIPSInst_FT(ir));
+ if (rv.l & 0x1)
+ DPFROMREG(rv.d, MIPSInst_FS(ir));
+ else
+ rv.l = 0;
+ break;
+
+ case fmaddf_op: {
+ union ieee754dp ft, fs, fd;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(maddf_d);
+ DPFROMREG(ft, MIPSInst_FT(ir));
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ DPFROMREG(fd, MIPSInst_FD(ir));
+ rv.d = ieee754dp_maddf(fd, fs, ft);
+ goto copcsr;
+ }
+
+ case fmsubf_op: {
+ union ieee754dp ft, fs, fd;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(msubf_d);
+ DPFROMREG(ft, MIPSInst_FT(ir));
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ DPFROMREG(fd, MIPSInst_FD(ir));
+ rv.d = ieee754dp_msubf(fd, fs, ft);
+ goto copcsr;
+ }
+
+ case frint_op: {
+ union ieee754dp fs;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(rint_d);
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.d = ieee754dp_rint(fs);
+ goto copcsr;
+ }
+
+ case fclass_op: {
+ union ieee754dp fs;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(class_d);
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.l = ieee754dp_2008class(fs);
+ rfmt = l_fmt;
+ goto copcsr;
+ }
+
+ case fmin_op: {
+ union ieee754dp fs, ft;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(min_d);
+ DPFROMREG(ft, MIPSInst_FT(ir));
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.d = ieee754dp_fmin(fs, ft);
+ goto copcsr;
+ }
+
+ case fmina_op: {
+ union ieee754dp fs, ft;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(mina_d);
+ DPFROMREG(ft, MIPSInst_FT(ir));
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.d = ieee754dp_fmina(fs, ft);
+ goto copcsr;
+ }
+
+ case fmax_op: {
+ union ieee754dp fs, ft;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(max_d);
+ DPFROMREG(ft, MIPSInst_FT(ir));
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.d = ieee754dp_fmax(fs, ft);
+ goto copcsr;
+ }
+
+ case fmaxa_op: {
+ union ieee754dp fs, ft;
+
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(maxa_d);
+ DPFROMREG(ft, MIPSInst_FT(ir));
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.d = ieee754dp_fmaxa(fs, ft);
+ goto copcsr;
+ }
+
+ case fabs_op:
+ MIPS_FPU_EMU_INC_STATS(abs_d);
+ handler.u = ieee754dp_abs;
+ goto dcopuop;
+
+ case fneg_op:
+ MIPS_FPU_EMU_INC_STATS(neg_d);
+ handler.u = ieee754dp_neg;
+ goto dcopuop;
+
+ case fmov_op:
+ /* an easy one */
+ MIPS_FPU_EMU_INC_STATS(mov_d);
+ DPFROMREG(rv.d, MIPSInst_FS(ir));
+ goto copcsr;
+
+ /* binary op on handler */
+dcopbop:
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ DPFROMREG(ft, MIPSInst_FT(ir));
+
+ rv.d = (*handler.b) (fs, ft);
+ goto copcsr;
+dcopuop:
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.d = (*handler.u) (fs);
+ goto copcsr;
+
+ /*
+ * unary conv ops
+ */
+ case fcvts_op:
+ MIPS_FPU_EMU_INC_STATS(cvt_s_d);
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.s = ieee754sp_fdp(fs);
+ rfmt = s_fmt;
+ goto copcsr;
+
+ case fcvtd_op:
+ return SIGILL; /* not defined */
+
+ case fcvtw_op:
+ MIPS_FPU_EMU_INC_STATS(cvt_w_d);
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.w = ieee754dp_tint(fs); /* wrong */
+ rfmt = w_fmt;
+ goto copcsr;
+
+ case fround_op:
+ case ftrunc_op:
+ case fceil_op:
+ case ffloor_op:
+ if (!cpu_has_mips_2_3_4_5_r)
+ return SIGILL;
+
+ if (MIPSInst_FUNC(ir) == fceil_op)
+ MIPS_FPU_EMU_INC_STATS(ceil_w_d);
+ if (MIPSInst_FUNC(ir) == ffloor_op)
+ MIPS_FPU_EMU_INC_STATS(floor_w_d);
+ if (MIPSInst_FUNC(ir) == fround_op)
+ MIPS_FPU_EMU_INC_STATS(round_w_d);
+ if (MIPSInst_FUNC(ir) == ftrunc_op)
+ MIPS_FPU_EMU_INC_STATS(trunc_w_d);
+
+ oldrm = ieee754_csr.rm;
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ ieee754_csr.rm = MIPSInst_FUNC(ir);
+ rv.w = ieee754dp_tint(fs);
+ ieee754_csr.rm = oldrm;
+ rfmt = w_fmt;
+ goto copcsr;
+
+ case fsel_op:
+ if (!cpu_has_mips_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(sel_d);
+ DPFROMREG(fd, MIPSInst_FD(ir));
+ if (fd.bits & 0x1)
+ DPFROMREG(rv.d, MIPSInst_FT(ir));
+ else
+ DPFROMREG(rv.d, MIPSInst_FS(ir));
+ break;
+
+ case fcvtl_op:
+ if (!cpu_has_mips_3_4_5_64_r2_r6)
+ return SIGILL;
+
+ MIPS_FPU_EMU_INC_STATS(cvt_l_d);
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ rv.l = ieee754dp_tlong(fs);
+ rfmt = l_fmt;
+ goto copcsr;
+
+ case froundl_op:
+ case ftruncl_op:
+ case fceill_op:
+ case ffloorl_op:
+ if (!cpu_has_mips_3_4_5_64_r2_r6)
+ return SIGILL;
+
+ if (MIPSInst_FUNC(ir) == fceill_op)
+ MIPS_FPU_EMU_INC_STATS(ceil_l_d);
+ if (MIPSInst_FUNC(ir) == ffloorl_op)
+ MIPS_FPU_EMU_INC_STATS(floor_l_d);
+ if (MIPSInst_FUNC(ir) == froundl_op)
+ MIPS_FPU_EMU_INC_STATS(round_l_d);
+ if (MIPSInst_FUNC(ir) == ftruncl_op)
+ MIPS_FPU_EMU_INC_STATS(trunc_l_d);
+
+ oldrm = ieee754_csr.rm;
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ ieee754_csr.rm = MIPSInst_FUNC(ir);
+ rv.l = ieee754dp_tlong(fs);
+ ieee754_csr.rm = oldrm;
+ rfmt = l_fmt;
+ goto copcsr;
+
+ default:
+ if (!NO_R6EMU && MIPSInst_FUNC(ir) >= fcmp_op) {
+ unsigned int cmpop;
+ union ieee754dp fs, ft;
+
+ cmpop = MIPSInst_FUNC(ir) - fcmp_op;
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ DPFROMREG(ft, MIPSInst_FT(ir));
+ rv.w = ieee754dp_cmp(fs, ft,
+ cmptab[cmpop & 0x7], cmpop & 0x8);
+ rfmt = -1;
+ if ((cmpop & 0x8)
+ &&
+ ieee754_cxtest
+ (IEEE754_INVALID_OPERATION))
+ rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
+ else
+ goto copcsr;
+
+ }
+ else {
+ return SIGILL;
+ }
+ break;
+ }
+ break;
+ }
+
+ case w_fmt: {
+ union ieee754dp fs;
+
+ switch (MIPSInst_FUNC(ir)) {
+ case fcvts_op:
+ /* convert word to single precision real */
+ MIPS_FPU_EMU_INC_STATS(cvt_s_w);
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.s = ieee754sp_fint(fs.bits);
+ rfmt = s_fmt;
+ goto copcsr;
+ case fcvtd_op:
+ /* convert word to double precision real */
+ MIPS_FPU_EMU_INC_STATS(cvt_d_w);
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ rv.d = ieee754dp_fint(fs.bits);
+ rfmt = d_fmt;
+ goto copcsr;
+ default: {
+ /* Emulating the new CMP.condn.fmt R6 instruction */
+#define CMPOP_MASK 0x7
+#define SIGN_BIT (0x1 << 3)
+#define PREDICATE_BIT (0x1 << 4)
+
+ int cmpop = MIPSInst_FUNC(ir) & CMPOP_MASK;
+ int sig = MIPSInst_FUNC(ir) & SIGN_BIT;
+ union ieee754sp fs, ft;
+
+ /* This is an R6 only instruction */
+ if (!cpu_has_mips_r6 ||
+ (MIPSInst_FUNC(ir) & 0x20))
+ return SIGILL;
+
+ if (!sig) {
+ if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
+ switch (cmpop) {
+ case 0:
+ MIPS_FPU_EMU_INC_STATS(cmp_af_s);
+ break;
+ case 1:
+ MIPS_FPU_EMU_INC_STATS(cmp_un_s);
+ break;
+ case 2:
+ MIPS_FPU_EMU_INC_STATS(cmp_eq_s);
+ break;
+ case 3:
+ MIPS_FPU_EMU_INC_STATS(cmp_ueq_s);
+ break;
+ case 4:
+ MIPS_FPU_EMU_INC_STATS(cmp_lt_s);
+ break;
+ case 5:
+ MIPS_FPU_EMU_INC_STATS(cmp_ult_s);
+ break;
+ case 6:
+ MIPS_FPU_EMU_INC_STATS(cmp_le_s);
+ break;
+ case 7:
+ MIPS_FPU_EMU_INC_STATS(cmp_ule_s);
+ break;
+ }
+ } else {
+ switch (cmpop) {
+ case 1:
+ MIPS_FPU_EMU_INC_STATS(cmp_or_s);
+ break;
+ case 2:
+ MIPS_FPU_EMU_INC_STATS(cmp_une_s);
+ break;
+ case 3:
+ MIPS_FPU_EMU_INC_STATS(cmp_ne_s);
+ break;
+ }
+ }
+ } else {
+ if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
+ switch (cmpop) {
+ case 0:
+ MIPS_FPU_EMU_INC_STATS(cmp_saf_s);
+ break;
+ case 1:
+ MIPS_FPU_EMU_INC_STATS(cmp_sun_s);
+ break;
+ case 2:
+ MIPS_FPU_EMU_INC_STATS(cmp_seq_s);
+ break;
+ case 3:
+ MIPS_FPU_EMU_INC_STATS(cmp_sueq_s);
+ break;
+ case 4:
+ MIPS_FPU_EMU_INC_STATS(cmp_slt_s);
+ break;
+ case 5:
+ MIPS_FPU_EMU_INC_STATS(cmp_sult_s);
+ break;
+ case 6:
+ MIPS_FPU_EMU_INC_STATS(cmp_sle_s);
+ break;
+ case 7:
+ MIPS_FPU_EMU_INC_STATS(cmp_sule_s);
+ break;
+ }
+ } else {
+ switch (cmpop) {
+ case 1:
+ MIPS_FPU_EMU_INC_STATS(cmp_sor_s);
+ break;
+ case 2:
+ MIPS_FPU_EMU_INC_STATS(cmp_sune_s);
+ break;
+ case 3:
+ MIPS_FPU_EMU_INC_STATS(cmp_sne_s);
+ break;
+ }
+ }
+ }
+
+ /* fmt is w_fmt for single precision so fix it */
+ rfmt = s_fmt;
+ /* default to false */
+ rv.w = 0;
+
+ /* CMP.condn.S */
+ SPFROMREG(fs, MIPSInst_FS(ir));
+ SPFROMREG(ft, MIPSInst_FT(ir));
+
+ /* positive predicates */
+ if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
+ if (ieee754sp_cmp(fs, ft, cmptab[cmpop],
+ sig))
+ rv.w = -1; /* true, all 1s */
+ if ((sig) &&
+ ieee754_cxtest(IEEE754_INVALID_OPERATION))
+ rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
+ else
+ goto copcsr;
+ } else {
+ /* negative predicates */
+ switch (cmpop) {
+ case 1:
+ case 2:
+ case 3:
+ if (ieee754sp_cmp(fs, ft,
+ negative_cmptab[cmpop],
+ sig))
+ rv.w = -1; /* true, all 1s */
+ if (sig &&
+ ieee754_cxtest(IEEE754_INVALID_OPERATION))
+ rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
+ else
+ goto copcsr;
+ break;
+ default:
+ /* Reserved R6 ops */
+ return SIGILL;
+ }
+ }
+ break;
+ }
+ }
+ break;
+ }
+
+ case l_fmt:
+
+ if (!cpu_has_mips_3_4_5_64_r2_r6)
+ return SIGILL;
+
+ DIFROMREG(bits, MIPSInst_FS(ir));
+
+ switch (MIPSInst_FUNC(ir)) {
+ case fcvts_op:
+ /* convert long to single precision real */
+ MIPS_FPU_EMU_INC_STATS(cvt_s_l);
+ rv.s = ieee754sp_flong(bits);
+ rfmt = s_fmt;
+ goto copcsr;
+ case fcvtd_op:
+ /* convert long to double precision real */
+ MIPS_FPU_EMU_INC_STATS(cvt_d_l);
+ rv.d = ieee754dp_flong(bits);
+ rfmt = d_fmt;
+ goto copcsr;
+ default: {
+ /* Emulating the new CMP.condn.fmt R6 instruction */
+ int cmpop = MIPSInst_FUNC(ir) & CMPOP_MASK;
+ int sig = MIPSInst_FUNC(ir) & SIGN_BIT;
+ union ieee754dp fs, ft;
+
+ if (!cpu_has_mips_r6 ||
+ (MIPSInst_FUNC(ir) & 0x20))
+ return SIGILL;
+
+ if (!sig) {
+ if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
+ switch (cmpop) {
+ case 0:
+ MIPS_FPU_EMU_INC_STATS(cmp_af_d);
+ break;
+ case 1:
+ MIPS_FPU_EMU_INC_STATS(cmp_un_d);
+ break;
+ case 2:
+ MIPS_FPU_EMU_INC_STATS(cmp_eq_d);
+ break;
+ case 3:
+ MIPS_FPU_EMU_INC_STATS(cmp_ueq_d);
+ break;
+ case 4:
+ MIPS_FPU_EMU_INC_STATS(cmp_lt_d);
+ break;
+ case 5:
+ MIPS_FPU_EMU_INC_STATS(cmp_ult_d);
+ break;
+ case 6:
+ MIPS_FPU_EMU_INC_STATS(cmp_le_d);
+ break;
+ case 7:
+ MIPS_FPU_EMU_INC_STATS(cmp_ule_d);
+ break;
+ }
+ } else {
+ switch (cmpop) {
+ case 1:
+ MIPS_FPU_EMU_INC_STATS(cmp_or_d);
+ break;
+ case 2:
+ MIPS_FPU_EMU_INC_STATS(cmp_une_d);
+ break;
+ case 3:
+ MIPS_FPU_EMU_INC_STATS(cmp_ne_d);
+ break;
+ }
+ }
+ } else {
+ if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
+ switch (cmpop) {
+ case 0:
+ MIPS_FPU_EMU_INC_STATS(cmp_saf_d);
+ break;
+ case 1:
+ MIPS_FPU_EMU_INC_STATS(cmp_sun_d);
+ break;
+ case 2:
+ MIPS_FPU_EMU_INC_STATS(cmp_seq_d);
+ break;
+ case 3:
+ MIPS_FPU_EMU_INC_STATS(cmp_sueq_d);
+ break;
+ case 4:
+ MIPS_FPU_EMU_INC_STATS(cmp_slt_d);
+ break;
+ case 5:
+ MIPS_FPU_EMU_INC_STATS(cmp_sult_d);
+ break;
+ case 6:
+ MIPS_FPU_EMU_INC_STATS(cmp_sle_d);
+ break;
+ case 7:
+ MIPS_FPU_EMU_INC_STATS(cmp_sule_d);
+ break;
+ }
+ } else {
+ switch (cmpop) {
+ case 1:
+ MIPS_FPU_EMU_INC_STATS(cmp_sor_d);
+ break;
+ case 2:
+ MIPS_FPU_EMU_INC_STATS(cmp_sune_d);
+ break;
+ case 3:
+ MIPS_FPU_EMU_INC_STATS(cmp_sne_d);
+ break;
+ }
+ }
+ }
+
+ /* fmt is l_fmt for double precision so fix it */
+ rfmt = d_fmt;
+ /* default to false */
+ rv.l = 0;
+
+ /* CMP.condn.D */
+ DPFROMREG(fs, MIPSInst_FS(ir));
+ DPFROMREG(ft, MIPSInst_FT(ir));
+
+ /* positive predicates */
+ if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
+ if (ieee754dp_cmp(fs, ft,
+ cmptab[cmpop], sig))
+ rv.l = -1LL; /* true, all 1s */
+ if (sig &&
+ ieee754_cxtest(IEEE754_INVALID_OPERATION))
+ rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
+ else
+ goto copcsr;
+ } else {
+ /* negative predicates */
+ switch (cmpop) {
+ case 1:
+ case 2:
+ case 3:
+ if (ieee754dp_cmp(fs, ft,
+ negative_cmptab[cmpop],
+ sig))
+ rv.l = -1LL; /* true, all 1s */
+ if (sig &&
+ ieee754_cxtest(IEEE754_INVALID_OPERATION))
+ rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
+ else
+ goto copcsr;
+ break;
+ default:
+ /* Reserved R6 ops */
+ return SIGILL;
+ }
+ }
+ break;
+ }
+ }
+ break;
+
+ default:
+ return SIGILL;
+ }
+
+ /*
+ * Update the fpu CSR register for this operation.
+ * If an exception is required, generate a tidy SIGFPE exception,
+ * without updating the result register.
+ * Note: cause exception bits do not accumulate, they are rewritten
+ * for each op; only the flag/sticky bits accumulate.
+ */
+ ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
+ if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
+ /*printk ("SIGFPE: FPU csr = %08x\n",ctx->fcr31); */
+ return SIGFPE;
+ }
+
+ /*
+ * Now we can safely write the result back to the register file.
+ */
+ switch (rfmt) {
+ case -1:
+
+ if (cpu_has_mips_4_5_r)
+ cbit = fpucondbit[MIPSInst_FD(ir) >> 2];
+ else
+ cbit = FPU_CSR_COND;
+ if (rv.w)
+ ctx->fcr31 |= cbit;
+ else
+ ctx->fcr31 &= ~cbit;
+ break;
+
+ case d_fmt:
+ DPTOREG(rv.d, MIPSInst_FD(ir));
+ break;
+ case s_fmt:
+ SPTOREG(rv.s, MIPSInst_FD(ir));
+ break;
+ case w_fmt:
+ SITOREG(rv.w, MIPSInst_FD(ir));
+ break;
+ case l_fmt:
+ if (!cpu_has_mips_3_4_5_64_r2_r6)
+ return SIGILL;
+
+ DITOREG(rv.l, MIPSInst_FD(ir));
+ break;
+ default:
+ return SIGILL;
+ }
+
+ return 0;
+}
+
+/*
+ * Emulate FPU instructions.
+ *
+ * If we use FPU hardware, then we have been typically called to handle
+ * an unimplemented operation, such as where an operand is a NaN or
+ * denormalized. In that case exit the emulation loop after a single
+ * iteration so as to let hardware execute any subsequent instructions.
+ *
+ * If we have no FPU hardware or it has been disabled, then continue
+ * emulating floating-point instructions until one of these conditions
+ * has occurred:
+ *
+ * - a non-FPU instruction has been encountered,
+ *
+ * - an attempt to emulate has ended with a signal,
+ *
+ * - the ISA mode has been switched.
+ *
+ * We need to terminate the emulation loop if we got switched to the
+ * MIPS16 mode, whether supported or not, so that we do not attempt
+ * to emulate a MIPS16 instruction as a regular MIPS FPU instruction.
+ * Similarly if we got switched to the microMIPS mode and only the
+ * regular MIPS mode is supported, so that we do not attempt to emulate
+ * a microMIPS instruction as a regular MIPS FPU instruction. Or if
+ * we got switched to the regular MIPS mode and only the microMIPS mode
+ * is supported, so that we do not attempt to emulate a regular MIPS
+ * instruction that should cause an Address Error exception instead.
+ * For simplicity we always terminate upon an ISA mode switch.
+ */
+int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
+ int has_fpu, void __user **fault_addr)
+{
+ unsigned long oldepc, prevepc;
+ struct mm_decoded_insn dec_insn;
+ u16 instr[4];
+ u16 *instr_ptr;
+ int sig = 0;
+
+ oldepc = xcp->cp0_epc;
+ do {
+ prevepc = xcp->cp0_epc;
+
+ if (get_isa16_mode(prevepc) && cpu_has_mmips) {
+ /*
+ * Get next 2 microMIPS instructions and convert them
+ * into 32-bit instructions.
+ */
+ if ((get_user(instr[0], (u16 __user *)msk_isa16_mode(xcp->cp0_epc))) ||
+ (get_user(instr[1], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 2))) ||
+ (get_user(instr[2], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 4))) ||
+ (get_user(instr[3], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 6)))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ return SIGBUS;
+ }
+ instr_ptr = instr;
+
+ /* Get first instruction. */
+ if (mm_insn_16bit(*instr_ptr)) {
+ /* Duplicate the half-word. */
+ dec_insn.insn = (*instr_ptr << 16) |
+ (*instr_ptr);
+ /* 16-bit instruction. */
+ dec_insn.pc_inc = 2;
+ instr_ptr += 1;
+ } else {
+ dec_insn.insn = (*instr_ptr << 16) |
+ *(instr_ptr+1);
+ /* 32-bit instruction. */
+ dec_insn.pc_inc = 4;
+ instr_ptr += 2;
+ }
+ /* Get second instruction. */
+ if (mm_insn_16bit(*instr_ptr)) {
+ /* Duplicate the half-word. */
+ dec_insn.next_insn = (*instr_ptr << 16) |
+ (*instr_ptr);
+ /* 16-bit instruction. */
+ dec_insn.next_pc_inc = 2;
+ } else {
+ dec_insn.next_insn = (*instr_ptr << 16) |
+ *(instr_ptr+1);
+ /* 32-bit instruction. */
+ dec_insn.next_pc_inc = 4;
+ }
+ dec_insn.micro_mips_mode = 1;
+ } else {
+ if ((get_user(dec_insn.insn,
+ (mips_instruction __user *) xcp->cp0_epc)) ||
+ (get_user(dec_insn.next_insn,
+ (mips_instruction __user *)(xcp->cp0_epc+4)))) {
+ MIPS_FPU_EMU_INC_STATS(errors);
+ return SIGBUS;
+ }
+ dec_insn.pc_inc = 4;
+ dec_insn.next_pc_inc = 4;
+ dec_insn.micro_mips_mode = 0;
+ }
+
+ if ((dec_insn.insn == 0) ||
+ ((dec_insn.pc_inc == 2) &&
+ ((dec_insn.insn & 0xffff) == MM_NOP16)))
+ xcp->cp0_epc += dec_insn.pc_inc; /* Skip NOPs */
+ else {
+ /*
+ * The 'ieee754_csr' is an alias of ctx->fcr31.
+ * No need to copy ctx->fcr31 to ieee754_csr.
+ */
+ sig = cop1Emulate(xcp, ctx, dec_insn, fault_addr);
+ }
+
+ if (has_fpu)
+ break;
+ if (sig)
+ break;
+ /*
+ * We have to check for the ISA bit explicitly here,
+ * because `get_isa16_mode' may return 0 if support
+ * for code compression has been globally disabled,
+ * or otherwise we may produce the wrong signal or
+ * even proceed successfully where we must not.
+ */
+ if ((xcp->cp0_epc ^ prevepc) & 0x1)
+ break;
+
+ cond_resched();
+ } while (xcp->cp0_epc > prevepc);
+
+ /* SIGILL indicates a non-fpu instruction */
+ if (sig == SIGILL && xcp->cp0_epc != oldepc)
+ /* but if EPC has advanced, then ignore it */
+ sig = 0;
+
+ return sig;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-12 00:47:34 +0000