From 102cedc32a6e3cd537374a3678d407591d5a6fab Mon Sep 17 00:00:00 2001 From: Leonid Yegoshin Date: Mon, 25 Mar 2013 12:09:02 -0500 Subject: [PATCH] MIPS: microMIPS: Floating point support. Add logic needed to do floating point emulation in microMIPS mode. Signed-off-by: Leonid Yegoshin Signed-off-by: Steven J. Hill --- arch/mips/include/asm/fpu_emulator.h | 6 + arch/mips/include/asm/inst.h | 9 + arch/mips/include/uapi/asm/inst.h | 5 + arch/mips/kernel/traps.c | 2 +- arch/mips/kernel/unaligned.c | 22 +- arch/mips/math-emu/cp1emu.c | 919 +++++++++++++++++++++++++++++++---- arch/mips/math-emu/dsemul.c | 30 +- 7 files changed, 893 insertions(+), 100 deletions(-) diff --git a/arch/mips/include/asm/fpu_emulator.h b/arch/mips/include/asm/fpu_emulator.h index 3b40927..2abb587 100644 --- a/arch/mips/include/asm/fpu_emulator.h +++ b/arch/mips/include/asm/fpu_emulator.h @@ -54,6 +54,12 @@ do { \ extern int mips_dsemul(struct pt_regs *regs, mips_instruction ir, unsigned long cpc); extern int do_dsemulret(struct pt_regs *xcp); +extern int fpu_emulator_cop1Handler(struct pt_regs *xcp, + struct mips_fpu_struct *ctx, int has_fpu, + void *__user *fault_addr); +int process_fpemu_return(int sig, void __user *fault_addr); +int mm_isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn, + unsigned long *contpc); /* * Instruction inserted following the badinst to further tag the sequence diff --git a/arch/mips/include/asm/inst.h b/arch/mips/include/asm/inst.h index f1eadf7..b27091e 100644 --- a/arch/mips/include/asm/inst.h +++ b/arch/mips/include/asm/inst.h @@ -73,4 +73,13 @@ typedef unsigned int mips_instruction; +/* microMIPS instruction decode structure. Do NOT export!!! */ +struct mm_decoded_insn { + mips_instruction insn; + mips_instruction next_insn; + int pc_inc; + int next_pc_inc; + int micro_mips_mode; +}; + #endif /* _ASM_INST_H */ diff --git a/arch/mips/include/uapi/asm/inst.h b/arch/mips/include/uapi/asm/inst.h index 4715337..23ec2f5 100644 --- a/arch/mips/include/uapi/asm/inst.h +++ b/arch/mips/include/uapi/asm/inst.h @@ -424,6 +424,11 @@ enum mm_16d_minor_op { }; /* + * (microMIPS & MIPS16e) NOP instruction. + */ +#define MM_NOP16 0x0c00 + +/* * Damn ... bitfields depend from byteorder :-( */ #ifdef __MIPSEB__ diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 4b6b607..333782b 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -675,7 +675,7 @@ asmlinkage void do_ov(struct pt_regs *regs) force_sig_info(SIGFPE, &info, current); } -static int process_fpemu_return(int sig, void __user *fault_addr) +int process_fpemu_return(int sig, void __user *fault_addr) { if (sig == SIGSEGV || sig == SIGBUS) { struct siginfo si = {0}; diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c index 6087a54..f4c94ff 100644 --- a/arch/mips/kernel/unaligned.c +++ b/arch/mips/kernel/unaligned.c @@ -83,6 +83,8 @@ #include #include #include +#include +#include #include #include @@ -108,6 +110,7 @@ static void emulate_load_store_insn(struct pt_regs *regs, union mips_instruction insn; unsigned long value; unsigned int res; + void __user *fault_addr = NULL; perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0); @@ -447,10 +450,21 @@ static void emulate_load_store_insn(struct pt_regs *regs, case ldc1_op: case swc1_op: case sdc1_op: - /* - * I herewith declare: this does not happen. So send SIGBUS. - */ - goto sigbus; + die_if_kernel("Unaligned FP access in kernel code", regs); + BUG_ON(!used_math()); + BUG_ON(!is_fpu_owner()); + + lose_fpu(1); /* Save FPU state for the emulator. */ + res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, + &fault_addr); + own_fpu(1); /* Restore FPU state. */ + + /* Signal if something went wrong. */ + process_fpemu_return(res, fault_addr); + + if (res == 0) + break; + return; /* * COP2 is available to implementor for application specific use. diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c index afb5a0b..f03771900 100644 --- a/arch/mips/math-emu/cp1emu.c +++ b/arch/mips/math-emu/cp1emu.c @@ -45,6 +45,7 @@ #include #include #include +#include #include #include @@ -81,6 +82,11 @@ DEFINE_PER_CPU(struct mips_fpu_emulator_stats, fpuemustats); /* Determine rounding mode from the RM bits of the FCSR */ #define modeindex(v) ((v) & FPU_CSR_RM) +/* microMIPS bitfields */ +#define MM_POOL32A_MINOR_MASK 0x3f +#define MM_POOL32A_MINOR_SHIFT 0x6 +#define MM_MIPS32_COND_FC 0x30 + /* Convert Mips rounding mode (0..3) to IEEE library modes. */ static const unsigned char ieee_rm[4] = { [FPU_CSR_RN] = IEEE754_RN, @@ -110,6 +116,556 @@ static const unsigned int fpucondbit[8] = { }; #endif +/* (microMIPS) Convert 16-bit register encoding to 32-bit register encoding. */ +static const unsigned int reg16to32map[8] = {16, 17, 2, 3, 4, 5, 6, 7}; + +/* (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: + 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 + op = ctc_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; + } + 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; + } + break; + default: + return SIGILL; + break; + } + + *insn_ptr = mips32_insn; + return 0; +} + +int mm_isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn, + unsigned long *contpc) +{ + union mips_instruction insn = (union mips_instruction)dec_insn.insn; + int bc_false = 0; + unsigned int fcr31; + unsigned int bit; + + switch (insn.mm_i_format.opcode) { + case mm_pool32a_op: + if ((insn.mm_i_format.simmediate & MM_POOL32A_MINOR_MASK) == + mm_pool32axf_op) { + switch (insn.mm_i_format.simmediate >> + MM_POOL32A_MINOR_SHIFT) { + case mm_jalr_op: + case mm_jalrhb_op: + case mm_jalrs_op: + case mm_jalrshb_op: + if (insn.mm_i_format.rt != 0) /* Not mm_jr */ + regs->regs[insn.mm_i_format.rt] = + regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + *contpc = regs->regs[insn.mm_i_format.rs]; + return 1; + break; + } + } + break; + case mm_pool32i_op: + switch (insn.mm_i_format.rt) { + case mm_bltzals_op: + case mm_bltzal_op: + regs->regs[31] = regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + /* Fall through */ + case mm_bltz_op: + if ((long)regs->regs[insn.mm_i_format.rs] < 0) + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + (insn.mm_i_format.simmediate << 1); + else + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + return 1; + break; + case mm_bgezals_op: + case mm_bgezal_op: + regs->regs[31] = regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + /* Fall through */ + case mm_bgez_op: + if ((long)regs->regs[insn.mm_i_format.rs] >= 0) + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + (insn.mm_i_format.simmediate << 1); + else + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + return 1; + break; + case mm_blez_op: + if ((long)regs->regs[insn.mm_i_format.rs] <= 0) + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + (insn.mm_i_format.simmediate << 1); + else + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + return 1; + break; + case mm_bgtz_op: + if ((long)regs->regs[insn.mm_i_format.rs] <= 0) + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + (insn.mm_i_format.simmediate << 1); + else + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + return 1; + break; + case mm_bc2f_op: + case mm_bc1f_op: + bc_false = 1; + /* Fall through */ + case mm_bc2t_op: + case mm_bc1t_op: + preempt_disable(); + if (is_fpu_owner()) + asm volatile("cfc1\t%0,$31" : "=r" (fcr31)); + else + fcr31 = current->thread.fpu.fcr31; + preempt_enable(); + + if (bc_false) + fcr31 = ~fcr31; + + bit = (insn.mm_i_format.rs >> 2); + bit += (bit != 0); + bit += 23; + if (fcr31 & (1 << bit)) + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + (insn.mm_i_format.simmediate << 1); + else + *contpc = regs->cp0_epc + + dec_insn.pc_inc + dec_insn.next_pc_inc; + return 1; + break; + } + break; + case mm_pool16c_op: + switch (insn.mm_i_format.rt) { + case mm_jalr16_op: + case mm_jalrs16_op: + regs->regs[31] = regs->cp0_epc + + dec_insn.pc_inc + dec_insn.next_pc_inc; + /* Fall through */ + case mm_jr16_op: + *contpc = regs->regs[insn.mm_i_format.rs]; + return 1; + break; + } + break; + case mm_beqz16_op: + if ((long)regs->regs[reg16to32map[insn.mm_b1_format.rs]] == 0) + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + (insn.mm_b1_format.simmediate << 1); + else + *contpc = regs->cp0_epc + + dec_insn.pc_inc + dec_insn.next_pc_inc; + return 1; + break; + case mm_bnez16_op: + if ((long)regs->regs[reg16to32map[insn.mm_b1_format.rs]] != 0) + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + (insn.mm_b1_format.simmediate << 1); + else + *contpc = regs->cp0_epc + + dec_insn.pc_inc + dec_insn.next_pc_inc; + return 1; + break; + case mm_b16_op: + *contpc = regs->cp0_epc + dec_insn.pc_inc + + (insn.mm_b0_format.simmediate << 1); + return 1; + break; + case mm_beq32_op: + if (regs->regs[insn.mm_i_format.rs] == + regs->regs[insn.mm_i_format.rt]) + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + (insn.mm_i_format.simmediate << 1); + else + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + return 1; + break; + case mm_bne32_op: + if (regs->regs[insn.mm_i_format.rs] != + regs->regs[insn.mm_i_format.rt]) + *contpc = regs->cp0_epc + + dec_insn.pc_inc + + (insn.mm_i_format.simmediate << 1); + else + *contpc = regs->cp0_epc + + dec_insn.pc_inc + dec_insn.next_pc_inc; + return 1; + break; + case mm_jalx32_op: + regs->regs[31] = regs->cp0_epc + + dec_insn.pc_inc + dec_insn.next_pc_inc; + *contpc = regs->cp0_epc + dec_insn.pc_inc; + *contpc >>= 28; + *contpc <<= 28; + *contpc |= (insn.j_format.target << 2); + return 1; + break; + case mm_jals32_op: + case mm_jal32_op: + regs->regs[31] = regs->cp0_epc + + dec_insn.pc_inc + dec_insn.next_pc_inc; + /* Fall through */ + case mm_j32_op: + *contpc = regs->cp0_epc + dec_insn.pc_inc; + *contpc >>= 27; + *contpc <<= 27; + *contpc |= (insn.j_format.target << 1); + set_isa16_mode(*contpc); + return 1; + break; + } + return 0; +} /* * Redundant with logic already in kernel/branch.c, @@ -117,53 +673,177 @@ static const unsigned int fpucondbit[8] = { * a single subroutine should be used across both * modules. */ -static int isBranchInstr(mips_instruction * i) +static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn, + unsigned long *contpc) { - switch (MIPSInst_OPCODE(*i)) { + union mips_instruction insn = (union mips_instruction)dec_insn.insn; + unsigned int fcr31; + unsigned int bit = 0; + + switch (insn.i_format.opcode) { case spec_op: - switch (MIPSInst_FUNC(*i)) { + switch (insn.r_format.func) { case jalr_op: + regs->regs[insn.r_format.rd] = + regs->cp0_epc + dec_insn.pc_inc + + dec_insn.next_pc_inc; + /* Fall through */ case jr_op: + *contpc = regs->regs[insn.r_format.rs]; return 1; + break; } break; - case bcond_op: - switch (MIPSInst_RT(*i)) { + switch (insn.i_format.rt) { + case bltzal_op: + case bltzall_op: + regs->regs[31] = regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + /* Fall through */ case bltz_op: - case bgez_op: case bltzl_op: - case bgezl_op: - case bltzal_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 bgezal_op: - case bltzall_op: case bgezall_op: + regs->regs[31] = regs->cp0_epc + + dec_insn.pc_inc + + dec_insn.next_pc_inc; + /* Fall through */ + case bgez_op: + case bgezl_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; } break; - - case j_op: - case jal_op: case jalx_op: + set_isa16_mode(bit); + 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; + break; case beq_op: - case bne_op: - case blez_op: - case bgtz_op: case beql_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; + break; + case bne_op: case bnel_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; + break; + case blez_op: case blezl_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 bgtz_op: case bgtzl_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 cop0_op: case cop1_op: case cop2_op: case cop1x_op: - if (MIPSInst_RS(*i) == bc_op) - return 1; + if (insn.i_format.rs == bc_op) { + preempt_disable(); + if (is_fpu_owner()) + asm volatile("cfc1\t%0,$31" : "=r" (fcr31)); + 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; + break; + 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; + } + } break; } - return 0; } @@ -210,26 +890,23 @@ static inline int cop1_64bit(struct pt_regs *xcp) */ static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx, - void *__user *fault_addr) + struct mm_decoded_insn dec_insn, void *__user *fault_addr) { mips_instruction ir; - unsigned long emulpc, contpc; + unsigned long contpc = xcp->cp0_epc + dec_insn.pc_inc; unsigned int cond; - - if (!access_ok(VERIFY_READ, xcp->cp0_epc, sizeof(mips_instruction))) { - MIPS_FPU_EMU_INC_STATS(errors); - *fault_addr = (mips_instruction __user *)xcp->cp0_epc; - return SIGBUS; - } - if (__get_user(ir, (mips_instruction __user *) xcp->cp0_epc)) { - MIPS_FPU_EMU_INC_STATS(errors); - *fault_addr = (mips_instruction __user *)xcp->cp0_epc; - return SIGSEGV; - } + int pc_inc; /* XXX NEC Vr54xx bug workaround */ - if ((xcp->cp0_cause & CAUSEF_BD) && !isBranchInstr(&ir)) - xcp->cp0_cause &= ~CAUSEF_BD; + if (xcp->cp0_cause & CAUSEF_BD) { + if (dec_insn.micro_mips_mode) { + if (!mm_isBranchInstr(xcp, dec_insn, &contpc)) + xcp->cp0_cause &= ~CAUSEF_BD; + } else { + if (!isBranchInstr(xcp, dec_insn, &contpc)) + xcp->cp0_cause &= ~CAUSEF_BD; + } + } if (xcp->cp0_cause & CAUSEF_BD) { /* @@ -244,32 +921,33 @@ static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx, * Linux MIPS branch emulator operates on context, updating the * cp0_epc. */ - emulpc = xcp->cp0_epc + 4; /* Snapshot emulation target */ + 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; + } - if (__compute_return_epc(xcp) < 0) { -#ifdef CP1DBG - printk("failed to emulate branch at %p\n", - (void *) (xcp->cp0_epc)); -#endif + /* + * 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; - } - if (!access_ok(VERIFY_READ, emulpc, sizeof(mips_instruction))) { - MIPS_FPU_EMU_INC_STATS(errors); - *fault_addr = (mips_instruction __user *)emulpc; - return SIGBUS; - } - if (__get_user(ir, (mips_instruction __user *) emulpc)) { - MIPS_FPU_EMU_INC_STATS(errors); - *fault_addr = (mips_instruction __user *)emulpc; - return SIGSEGV; - } - /* __compute_return_epc() will have updated cp0_epc */ - contpc = xcp->cp0_epc; - /* In order not to confuse ptrace() et al, tweak context */ - xcp->cp0_epc = emulpc - 4; - } else { - emulpc = xcp->cp0_epc; - contpc = xcp->cp0_epc + 4; } emul: @@ -474,22 +1152,35 @@ static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx, /* branch taken: emulate dslot * instruction */ - xcp->cp0_epc += 4; - contpc = (xcp->cp0_epc + - (MIPSInst_SIMM(ir) << 2)); - - if (!access_ok(VERIFY_READ, xcp->cp0_epc, - sizeof(mips_instruction))) { - MIPS_FPU_EMU_INC_STATS(errors); - *fault_addr = (mips_instruction __user *)xcp->cp0_epc; - return SIGBUS; - } - if (__get_user(ir, - (mips_instruction __user *) xcp->cp0_epc)) { - MIPS_FPU_EMU_INC_STATS(errors); - *fault_addr = (mips_instruction __user *)xcp->cp0_epc; - return SIGSEGV; - } + 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. + */ + return mips_dsemul(xcp, ir, contpc); + } + } else + contpc = (xcp->cp0_epc + (contpc << 2)); switch (MIPSInst_OPCODE(ir)) { case lwc1_op: @@ -525,8 +1216,8 @@ static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx, * branch likely nullifies * dslot if not taken */ - xcp->cp0_epc += 4; - contpc += 4; + xcp->cp0_epc += dec_insn.pc_inc; + contpc += dec_insn.pc_inc; /* * else continue & execute * dslot as normal insn @@ -1313,25 +2004,75 @@ int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx, int has_fpu, void *__user *fault_addr) { unsigned long oldepc, prevepc; - mips_instruction insn; + 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 (!access_ok(VERIFY_READ, xcp->cp0_epc, sizeof(mips_instruction))) { - MIPS_FPU_EMU_INC_STATS(errors); - *fault_addr = (mips_instruction __user *)xcp->cp0_epc; - return SIGBUS; - } - if (__get_user(insn, (mips_instruction __user *) xcp->cp0_epc)) { - MIPS_FPU_EMU_INC_STATS(errors); - *fault_addr = (mips_instruction __user *)xcp->cp0_epc; - return SIGSEGV; + 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 (insn == 0) - xcp->cp0_epc += 4; /* skip nops */ + + 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 @@ -1341,7 +2082,7 @@ int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx, */ /* convert to ieee library modes */ ieee754_csr.rm = ieee_rm[ieee754_csr.rm]; - sig = cop1Emulate(xcp, ctx, fault_addr); + sig = cop1Emulate(xcp, ctx, dec_insn, fault_addr); /* revert to mips rounding mode */ ieee754_csr.rm = mips_rm[ieee754_csr.rm]; } diff --git a/arch/mips/math-emu/dsemul.c b/arch/mips/math-emu/dsemul.c index 384a3b0..7ea622a 100644 --- a/arch/mips/math-emu/dsemul.c +++ b/arch/mips/math-emu/dsemul.c @@ -55,7 +55,9 @@ int mips_dsemul(struct pt_regs *regs, mips_instruction ir, unsigned long cpc) struct emuframe __user *fr; int err; - if (ir == 0) { /* a nop is easy */ + if ((get_isa16_mode(regs->cp0_epc) && ((ir >> 16) == MM_NOP16)) || + (ir == 0)) { + /* NOP is easy */ regs->cp0_epc = cpc; regs->cp0_cause &= ~CAUSEF_BD; return 0; @@ -91,8 +93,16 @@ int mips_dsemul(struct pt_regs *regs, mips_instruction ir, unsigned long cpc) if (unlikely(!access_ok(VERIFY_WRITE, fr, sizeof(struct emuframe)))) return SIGBUS; - err = __put_user(ir, &fr->emul); - err |= __put_user((mips_instruction)BREAK_MATH, &fr->badinst); + if (get_isa16_mode(regs->cp0_epc)) { + err = __put_user(ir >> 16, (u16 __user *)(&fr->emul)); + err |= __put_user(ir & 0xffff, (u16 __user *)((long)(&fr->emul) + 2)); + err |= __put_user(BREAK_MATH >> 16, (u16 __user *)(&fr->badinst)); + err |= __put_user(BREAK_MATH & 0xffff, (u16 __user *)((long)(&fr->badinst) + 2)); + } else { + err = __put_user(ir, &fr->emul); + err |= __put_user((mips_instruction)BREAK_MATH, &fr->badinst); + } + err |= __put_user((mips_instruction)BD_COOKIE, &fr->cookie); err |= __put_user(cpc, &fr->epc); @@ -101,7 +111,8 @@ int mips_dsemul(struct pt_regs *regs, mips_instruction ir, unsigned long cpc) return SIGBUS; } - regs->cp0_epc = (unsigned long) &fr->emul; + regs->cp0_epc = ((unsigned long) &fr->emul) | + get_isa16_mode(regs->cp0_epc); flush_cache_sigtramp((unsigned long)&fr->badinst); @@ -114,9 +125,10 @@ int do_dsemulret(struct pt_regs *xcp) unsigned long epc; u32 insn, cookie; int err = 0; + u16 instr[2]; fr = (struct emuframe __user *) - (xcp->cp0_epc - sizeof(mips_instruction)); + (msk_isa16_mode(xcp->cp0_epc) - sizeof(mips_instruction)); /* * If we can't even access the area, something is very wrong, but we'll @@ -131,7 +143,13 @@ int do_dsemulret(struct pt_regs *xcp) * - Is the instruction pointed to by the EPC an BREAK_MATH? * - Is the following memory word the BD_COOKIE? */ - err = __get_user(insn, &fr->badinst); + if (get_isa16_mode(xcp->cp0_epc)) { + err = __get_user(instr[0], (u16 __user *)(&fr->badinst)); + err |= __get_user(instr[1], (u16 __user *)((long)(&fr->badinst) + 2)); + insn = (instr[0] << 16) | instr[1]; + } else { + err = __get_user(insn, &fr->badinst); + } err |= __get_user(cookie, &fr->cookie); if (unlikely(err || (insn != BREAK_MATH) || (cookie != BD_COOKIE))) { -- 2.7.4