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-rw-r--r--arch/mips/kernel/mips-r2-to-r6-emul.c2405
1 files changed, 2405 insertions, 0 deletions
diff --git a/arch/mips/kernel/mips-r2-to-r6-emul.c b/arch/mips/kernel/mips-r2-to-r6-emul.c
new file mode 100644
index 000000000..eb18b186e
--- /dev/null
+++ b/arch/mips/kernel/mips-r2-to-r6-emul.c
@@ -0,0 +1,2405 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2014 Imagination Technologies Ltd.
+ * Author: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
+ * Author: Markos Chandras <markos.chandras@imgtec.com>
+ *
+ * MIPS R2 user space instruction emulator for MIPS R6
+ *
+ */
+#include <linux/bug.h>
+#include <linux/compiler.h>
+#include <linux/debugfs.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/ptrace.h>
+#include <linux/seq_file.h>
+
+#include <asm/asm.h>
+#include <asm/branch.h>
+#include <asm/break.h>
+#include <asm/debug.h>
+#include <asm/fpu.h>
+#include <asm/fpu_emulator.h>
+#include <asm/inst.h>
+#include <asm/mips-r2-to-r6-emul.h>
+#include <asm/local.h>
+#include <asm/mipsregs.h>
+#include <asm/ptrace.h>
+#include <linux/uaccess.h>
+
+#ifdef CONFIG_64BIT
+#define ADDIU "daddiu "
+#define INS "dins "
+#define EXT "dext "
+#else
+#define ADDIU "addiu "
+#define INS "ins "
+#define EXT "ext "
+#endif /* CONFIG_64BIT */
+
+#define SB "sb "
+#define LB "lb "
+#define LL "ll "
+#define SC "sc "
+
+#ifdef CONFIG_DEBUG_FS
+static DEFINE_PER_CPU(struct mips_r2_emulator_stats, mipsr2emustats);
+static DEFINE_PER_CPU(struct mips_r2_emulator_stats, mipsr2bdemustats);
+static DEFINE_PER_CPU(struct mips_r2br_emulator_stats, mipsr2bremustats);
+#endif
+
+extern const unsigned int fpucondbit[8];
+
+#define MIPS_R2_EMUL_TOTAL_PASS 10
+
+int mipsr2_emulation = 0;
+
+static int __init mipsr2emu_enable(char *s)
+{
+ mipsr2_emulation = 1;
+
+ pr_info("MIPS R2-to-R6 Emulator Enabled!");
+
+ return 1;
+}
+__setup("mipsr2emu", mipsr2emu_enable);
+
+/**
+ * mipsr6_emul - Emulate some frequent R2/R5/R6 instructions in delay slot
+ * for performance instead of the traditional way of using a stack trampoline
+ * which is rather slow.
+ * @regs: Process register set
+ * @ir: Instruction
+ */
+static inline int mipsr6_emul(struct pt_regs *regs, u32 ir)
+{
+ switch (MIPSInst_OPCODE(ir)) {
+ case addiu_op:
+ if (MIPSInst_RT(ir))
+ regs->regs[MIPSInst_RT(ir)] =
+ (s32)regs->regs[MIPSInst_RS(ir)] +
+ (s32)MIPSInst_SIMM(ir);
+ return 0;
+ case daddiu_op:
+ if (IS_ENABLED(CONFIG_32BIT))
+ break;
+
+ if (MIPSInst_RT(ir))
+ regs->regs[MIPSInst_RT(ir)] =
+ (s64)regs->regs[MIPSInst_RS(ir)] +
+ (s64)MIPSInst_SIMM(ir);
+ return 0;
+ case lwc1_op:
+ case swc1_op:
+ case cop1_op:
+ case cop1x_op:
+ /* FPU instructions in delay slot */
+ return -SIGFPE;
+ case spec_op:
+ switch (MIPSInst_FUNC(ir)) {
+ case or_op:
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] =
+ regs->regs[MIPSInst_RS(ir)] |
+ regs->regs[MIPSInst_RT(ir)];
+ return 0;
+ case sll_op:
+ if (MIPSInst_RS(ir))
+ break;
+
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] =
+ (s32)(((u32)regs->regs[MIPSInst_RT(ir)]) <<
+ MIPSInst_FD(ir));
+ return 0;
+ case srl_op:
+ if (MIPSInst_RS(ir))
+ break;
+
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] =
+ (s32)(((u32)regs->regs[MIPSInst_RT(ir)]) >>
+ MIPSInst_FD(ir));
+ return 0;
+ case addu_op:
+ if (MIPSInst_FD(ir))
+ break;
+
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] =
+ (s32)((u32)regs->regs[MIPSInst_RS(ir)] +
+ (u32)regs->regs[MIPSInst_RT(ir)]);
+ return 0;
+ case subu_op:
+ if (MIPSInst_FD(ir))
+ break;
+
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] =
+ (s32)((u32)regs->regs[MIPSInst_RS(ir)] -
+ (u32)regs->regs[MIPSInst_RT(ir)]);
+ return 0;
+ case dsll_op:
+ if (IS_ENABLED(CONFIG_32BIT) || MIPSInst_RS(ir))
+ break;
+
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] =
+ (s64)(((u64)regs->regs[MIPSInst_RT(ir)]) <<
+ MIPSInst_FD(ir));
+ return 0;
+ case dsrl_op:
+ if (IS_ENABLED(CONFIG_32BIT) || MIPSInst_RS(ir))
+ break;
+
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] =
+ (s64)(((u64)regs->regs[MIPSInst_RT(ir)]) >>
+ MIPSInst_FD(ir));
+ return 0;
+ case daddu_op:
+ if (IS_ENABLED(CONFIG_32BIT) || MIPSInst_FD(ir))
+ break;
+
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] =
+ (u64)regs->regs[MIPSInst_RS(ir)] +
+ (u64)regs->regs[MIPSInst_RT(ir)];
+ return 0;
+ case dsubu_op:
+ if (IS_ENABLED(CONFIG_32BIT) || MIPSInst_FD(ir))
+ break;
+
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] =
+ (s64)((u64)regs->regs[MIPSInst_RS(ir)] -
+ (u64)regs->regs[MIPSInst_RT(ir)]);
+ return 0;
+ }
+ break;
+ default:
+ pr_debug("No fastpath BD emulation for instruction 0x%08x (op: %02x)\n",
+ ir, MIPSInst_OPCODE(ir));
+ }
+
+ return SIGILL;
+}
+
+/**
+ * movf_func - Emulate a MOVF instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int movf_func(struct pt_regs *regs, u32 ir)
+{
+ u32 csr;
+ u32 cond;
+
+ csr = current->thread.fpu.fcr31;
+ cond = fpucondbit[MIPSInst_RT(ir) >> 2];
+
+ if (((csr & cond) == 0) && MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
+
+ MIPS_R2_STATS(movs);
+
+ return 0;
+}
+
+/**
+ * movt_func - Emulate a MOVT instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int movt_func(struct pt_regs *regs, u32 ir)
+{
+ u32 csr;
+ u32 cond;
+
+ csr = current->thread.fpu.fcr31;
+ cond = fpucondbit[MIPSInst_RT(ir) >> 2];
+
+ if (((csr & cond) != 0) && MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
+
+ MIPS_R2_STATS(movs);
+
+ return 0;
+}
+
+/**
+ * jr_func - Emulate a JR instruction.
+ * @pt_regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns SIGILL if JR was in delay slot, SIGEMT if we
+ * can't compute the EPC, SIGSEGV if we can't access the
+ * userland instruction or 0 on success.
+ */
+static int jr_func(struct pt_regs *regs, u32 ir)
+{
+ int err;
+ unsigned long cepc, epc, nepc;
+ u32 nir;
+
+ if (delay_slot(regs))
+ return SIGILL;
+
+ /* EPC after the RI/JR instruction */
+ nepc = regs->cp0_epc;
+ /* Roll back to the reserved R2 JR instruction */
+ regs->cp0_epc -= 4;
+ epc = regs->cp0_epc;
+ err = __compute_return_epc(regs);
+
+ if (err < 0)
+ return SIGEMT;
+
+
+ /* Computed EPC */
+ cepc = regs->cp0_epc;
+
+ /* Get DS instruction */
+ err = __get_user(nir, (u32 __user *)nepc);
+ if (err)
+ return SIGSEGV;
+
+ MIPS_R2BR_STATS(jrs);
+
+ /* If nir == 0(NOP), then nothing else to do */
+ if (nir) {
+ /*
+ * Negative err means FPU instruction in BD-slot,
+ * Zero err means 'BD-slot emulation done'
+ * For anything else we go back to trampoline emulation.
+ */
+ err = mipsr6_emul(regs, nir);
+ if (err > 0) {
+ regs->cp0_epc = nepc;
+ err = mips_dsemul(regs, nir, epc, cepc);
+ if (err == SIGILL)
+ err = SIGEMT;
+ MIPS_R2_STATS(dsemul);
+ }
+ }
+
+ return err;
+}
+
+/**
+ * movz_func - Emulate a MOVZ instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int movz_func(struct pt_regs *regs, u32 ir)
+{
+ if (((regs->regs[MIPSInst_RT(ir)]) == 0) && MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
+ MIPS_R2_STATS(movs);
+
+ return 0;
+}
+
+/**
+ * movn_func - Emulate a MOVZ instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int movn_func(struct pt_regs *regs, u32 ir)
+{
+ if (((regs->regs[MIPSInst_RT(ir)]) != 0) && MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
+ MIPS_R2_STATS(movs);
+
+ return 0;
+}
+
+/**
+ * mfhi_func - Emulate a MFHI instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int mfhi_func(struct pt_regs *regs, u32 ir)
+{
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] = regs->hi;
+
+ MIPS_R2_STATS(hilo);
+
+ return 0;
+}
+
+/**
+ * mthi_func - Emulate a MTHI instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int mthi_func(struct pt_regs *regs, u32 ir)
+{
+ regs->hi = regs->regs[MIPSInst_RS(ir)];
+
+ MIPS_R2_STATS(hilo);
+
+ return 0;
+}
+
+/**
+ * mflo_func - Emulate a MFLO instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int mflo_func(struct pt_regs *regs, u32 ir)
+{
+ if (MIPSInst_RD(ir))
+ regs->regs[MIPSInst_RD(ir)] = regs->lo;
+
+ MIPS_R2_STATS(hilo);
+
+ return 0;
+}
+
+/**
+ * mtlo_func - Emulate a MTLO instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int mtlo_func(struct pt_regs *regs, u32 ir)
+{
+ regs->lo = regs->regs[MIPSInst_RS(ir)];
+
+ MIPS_R2_STATS(hilo);
+
+ return 0;
+}
+
+/**
+ * mult_func - Emulate a MULT instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int mult_func(struct pt_regs *regs, u32 ir)
+{
+ s64 res;
+ s32 rt, rs;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+ res = (s64)rt * (s64)rs;
+
+ rs = res;
+ regs->lo = (s64)rs;
+ rt = res >> 32;
+ res = (s64)rt;
+ regs->hi = res;
+
+ MIPS_R2_STATS(muls);
+
+ return 0;
+}
+
+/**
+ * multu_func - Emulate a MULTU instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int multu_func(struct pt_regs *regs, u32 ir)
+{
+ u64 res;
+ u32 rt, rs;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+ res = (u64)rt * (u64)rs;
+ rt = res;
+ regs->lo = (s64)(s32)rt;
+ regs->hi = (s64)(s32)(res >> 32);
+
+ MIPS_R2_STATS(muls);
+
+ return 0;
+}
+
+/**
+ * div_func - Emulate a DIV instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int div_func(struct pt_regs *regs, u32 ir)
+{
+ s32 rt, rs;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+
+ regs->lo = (s64)(rs / rt);
+ regs->hi = (s64)(rs % rt);
+
+ MIPS_R2_STATS(divs);
+
+ return 0;
+}
+
+/**
+ * divu_func - Emulate a DIVU instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int divu_func(struct pt_regs *regs, u32 ir)
+{
+ u32 rt, rs;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+
+ regs->lo = (s64)(rs / rt);
+ regs->hi = (s64)(rs % rt);
+
+ MIPS_R2_STATS(divs);
+
+ return 0;
+}
+
+/**
+ * dmult_func - Emulate a DMULT instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 on success or SIGILL for 32-bit kernels.
+ */
+static int dmult_func(struct pt_regs *regs, u32 ir)
+{
+ s64 res;
+ s64 rt, rs;
+
+ if (IS_ENABLED(CONFIG_32BIT))
+ return SIGILL;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+ res = rt * rs;
+
+ regs->lo = res;
+ __asm__ __volatile__(
+ "dmuh %0, %1, %2\t\n"
+ : "=r"(res)
+ : "r"(rt), "r"(rs));
+
+ regs->hi = res;
+
+ MIPS_R2_STATS(muls);
+
+ return 0;
+}
+
+/**
+ * dmultu_func - Emulate a DMULTU instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 on success or SIGILL for 32-bit kernels.
+ */
+static int dmultu_func(struct pt_regs *regs, u32 ir)
+{
+ u64 res;
+ u64 rt, rs;
+
+ if (IS_ENABLED(CONFIG_32BIT))
+ return SIGILL;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+ res = rt * rs;
+
+ regs->lo = res;
+ __asm__ __volatile__(
+ "dmuhu %0, %1, %2\t\n"
+ : "=r"(res)
+ : "r"(rt), "r"(rs));
+
+ regs->hi = res;
+
+ MIPS_R2_STATS(muls);
+
+ return 0;
+}
+
+/**
+ * ddiv_func - Emulate a DDIV instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 on success or SIGILL for 32-bit kernels.
+ */
+static int ddiv_func(struct pt_regs *regs, u32 ir)
+{
+ s64 rt, rs;
+
+ if (IS_ENABLED(CONFIG_32BIT))
+ return SIGILL;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+
+ regs->lo = rs / rt;
+ regs->hi = rs % rt;
+
+ MIPS_R2_STATS(divs);
+
+ return 0;
+}
+
+/**
+ * ddivu_func - Emulate a DDIVU instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 on success or SIGILL for 32-bit kernels.
+ */
+static int ddivu_func(struct pt_regs *regs, u32 ir)
+{
+ u64 rt, rs;
+
+ if (IS_ENABLED(CONFIG_32BIT))
+ return SIGILL;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+
+ regs->lo = rs / rt;
+ regs->hi = rs % rt;
+
+ MIPS_R2_STATS(divs);
+
+ return 0;
+}
+
+/* R6 removed instructions for the SPECIAL opcode */
+static const struct r2_decoder_table spec_op_table[] = {
+ { 0xfc1ff83f, 0x00000008, jr_func },
+ { 0xfc00ffff, 0x00000018, mult_func },
+ { 0xfc00ffff, 0x00000019, multu_func },
+ { 0xfc00ffff, 0x0000001c, dmult_func },
+ { 0xfc00ffff, 0x0000001d, dmultu_func },
+ { 0xffff07ff, 0x00000010, mfhi_func },
+ { 0xfc1fffff, 0x00000011, mthi_func },
+ { 0xffff07ff, 0x00000012, mflo_func },
+ { 0xfc1fffff, 0x00000013, mtlo_func },
+ { 0xfc0307ff, 0x00000001, movf_func },
+ { 0xfc0307ff, 0x00010001, movt_func },
+ { 0xfc0007ff, 0x0000000a, movz_func },
+ { 0xfc0007ff, 0x0000000b, movn_func },
+ { 0xfc00ffff, 0x0000001a, div_func },
+ { 0xfc00ffff, 0x0000001b, divu_func },
+ { 0xfc00ffff, 0x0000001e, ddiv_func },
+ { 0xfc00ffff, 0x0000001f, ddivu_func },
+ {}
+};
+
+/**
+ * madd_func - Emulate a MADD instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int madd_func(struct pt_regs *regs, u32 ir)
+{
+ s64 res;
+ s32 rt, rs;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+ res = (s64)rt * (s64)rs;
+ rt = regs->hi;
+ rs = regs->lo;
+ res += ((((s64)rt) << 32) | (u32)rs);
+
+ rt = res;
+ regs->lo = (s64)rt;
+ rs = res >> 32;
+ regs->hi = (s64)rs;
+
+ MIPS_R2_STATS(dsps);
+
+ return 0;
+}
+
+/**
+ * maddu_func - Emulate a MADDU instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int maddu_func(struct pt_regs *regs, u32 ir)
+{
+ u64 res;
+ u32 rt, rs;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+ res = (u64)rt * (u64)rs;
+ rt = regs->hi;
+ rs = regs->lo;
+ res += ((((s64)rt) << 32) | (u32)rs);
+
+ rt = res;
+ regs->lo = (s64)(s32)rt;
+ rs = res >> 32;
+ regs->hi = (s64)(s32)rs;
+
+ MIPS_R2_STATS(dsps);
+
+ return 0;
+}
+
+/**
+ * msub_func - Emulate a MSUB instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int msub_func(struct pt_regs *regs, u32 ir)
+{
+ s64 res;
+ s32 rt, rs;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+ res = (s64)rt * (s64)rs;
+ rt = regs->hi;
+ rs = regs->lo;
+ res = ((((s64)rt) << 32) | (u32)rs) - res;
+
+ rt = res;
+ regs->lo = (s64)rt;
+ rs = res >> 32;
+ regs->hi = (s64)rs;
+
+ MIPS_R2_STATS(dsps);
+
+ return 0;
+}
+
+/**
+ * msubu_func - Emulate a MSUBU instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int msubu_func(struct pt_regs *regs, u32 ir)
+{
+ u64 res;
+ u32 rt, rs;
+
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+ res = (u64)rt * (u64)rs;
+ rt = regs->hi;
+ rs = regs->lo;
+ res = ((((s64)rt) << 32) | (u32)rs) - res;
+
+ rt = res;
+ regs->lo = (s64)(s32)rt;
+ rs = res >> 32;
+ regs->hi = (s64)(s32)rs;
+
+ MIPS_R2_STATS(dsps);
+
+ return 0;
+}
+
+/**
+ * mul_func - Emulate a MUL instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int mul_func(struct pt_regs *regs, u32 ir)
+{
+ s64 res;
+ s32 rt, rs;
+
+ if (!MIPSInst_RD(ir))
+ return 0;
+ rt = regs->regs[MIPSInst_RT(ir)];
+ rs = regs->regs[MIPSInst_RS(ir)];
+ res = (s64)rt * (s64)rs;
+
+ rs = res;
+ regs->regs[MIPSInst_RD(ir)] = (s64)rs;
+
+ MIPS_R2_STATS(muls);
+
+ return 0;
+}
+
+/**
+ * clz_func - Emulate a CLZ instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int clz_func(struct pt_regs *regs, u32 ir)
+{
+ u32 res;
+ u32 rs;
+
+ if (!MIPSInst_RD(ir))
+ return 0;
+
+ rs = regs->regs[MIPSInst_RS(ir)];
+ __asm__ __volatile__("clz %0, %1" : "=r"(res) : "r"(rs));
+ regs->regs[MIPSInst_RD(ir)] = res;
+
+ MIPS_R2_STATS(bops);
+
+ return 0;
+}
+
+/**
+ * clo_func - Emulate a CLO instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+
+static int clo_func(struct pt_regs *regs, u32 ir)
+{
+ u32 res;
+ u32 rs;
+
+ if (!MIPSInst_RD(ir))
+ return 0;
+
+ rs = regs->regs[MIPSInst_RS(ir)];
+ __asm__ __volatile__("clo %0, %1" : "=r"(res) : "r"(rs));
+ regs->regs[MIPSInst_RD(ir)] = res;
+
+ MIPS_R2_STATS(bops);
+
+ return 0;
+}
+
+/**
+ * dclz_func - Emulate a DCLZ instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int dclz_func(struct pt_regs *regs, u32 ir)
+{
+ u64 res;
+ u64 rs;
+
+ if (IS_ENABLED(CONFIG_32BIT))
+ return SIGILL;
+
+ if (!MIPSInst_RD(ir))
+ return 0;
+
+ rs = regs->regs[MIPSInst_RS(ir)];
+ __asm__ __volatile__("dclz %0, %1" : "=r"(res) : "r"(rs));
+ regs->regs[MIPSInst_RD(ir)] = res;
+
+ MIPS_R2_STATS(bops);
+
+ return 0;
+}
+
+/**
+ * dclo_func - Emulate a DCLO instruction
+ * @regs: Process register set
+ * @ir: Instruction
+ *
+ * Returns 0 since it always succeeds.
+ */
+static int dclo_func(struct pt_regs *regs, u32 ir)
+{
+ u64 res;
+ u64 rs;
+
+ if (IS_ENABLED(CONFIG_32BIT))
+ return SIGILL;
+
+ if (!MIPSInst_RD(ir))
+ return 0;
+
+ rs = regs->regs[MIPSInst_RS(ir)];
+ __asm__ __volatile__("dclo %0, %1" : "=r"(res) : "r"(rs));
+ regs->regs[MIPSInst_RD(ir)] = res;
+
+ MIPS_R2_STATS(bops);
+
+ return 0;
+}
+
+/* R6 removed instructions for the SPECIAL2 opcode */
+static const struct r2_decoder_table spec2_op_table[] = {
+ { 0xfc00ffff, 0x70000000, madd_func },
+ { 0xfc00ffff, 0x70000001, maddu_func },
+ { 0xfc0007ff, 0x70000002, mul_func },
+ { 0xfc00ffff, 0x70000004, msub_func },
+ { 0xfc00ffff, 0x70000005, msubu_func },
+ { 0xfc0007ff, 0x70000020, clz_func },
+ { 0xfc0007ff, 0x70000021, clo_func },
+ { 0xfc0007ff, 0x70000024, dclz_func },
+ { 0xfc0007ff, 0x70000025, dclo_func },
+ { }
+};
+
+static inline int mipsr2_find_op_func(struct pt_regs *regs, u32 inst,
+ const struct r2_decoder_table *table)
+{
+ const struct r2_decoder_table *p;
+ int err;
+
+ for (p = table; p->func; p++) {
+ if ((inst & p->mask) == p->code) {
+ err = (p->func)(regs, inst);
+ return err;
+ }
+ }
+ return SIGILL;
+}
+
+/**
+ * mipsr2_decoder: Decode and emulate a MIPS R2 instruction
+ * @regs: Process register set
+ * @inst: Instruction to decode and emulate
+ * @fcr31: Floating Point Control and Status Register Cause bits returned
+ */
+int mipsr2_decoder(struct pt_regs *regs, u32 inst, unsigned long *fcr31)
+{
+ int err = 0;
+ unsigned long vaddr;
+ u32 nir;
+ unsigned long cpc, epc, nepc, r31, res, rs, rt;
+
+ void __user *fault_addr = NULL;
+ int pass = 0;
+
+repeat:
+ r31 = regs->regs[31];
+ epc = regs->cp0_epc;
+ err = compute_return_epc(regs);
+ if (err < 0) {
+ BUG();
+ return SIGEMT;
+ }
+ pr_debug("Emulating the 0x%08x R2 instruction @ 0x%08lx (pass=%d))\n",
+ inst, epc, pass);
+
+ switch (MIPSInst_OPCODE(inst)) {
+ case spec_op:
+ err = mipsr2_find_op_func(regs, inst, spec_op_table);
+ if (err < 0) {
+ /* FPU instruction under JR */
+ regs->cp0_cause |= CAUSEF_BD;
+ goto fpu_emul;
+ }
+ break;
+ case spec2_op:
+ err = mipsr2_find_op_func(regs, inst, spec2_op_table);
+ break;
+ case bcond_op:
+ rt = MIPSInst_RT(inst);
+ rs = MIPSInst_RS(inst);
+ switch (rt) {
+ case tgei_op:
+ if ((long)regs->regs[rs] >= MIPSInst_SIMM(inst))
+ do_trap_or_bp(regs, 0, 0, "TGEI");
+
+ MIPS_R2_STATS(traps);
+
+ break;
+ case tgeiu_op:
+ if (regs->regs[rs] >= MIPSInst_UIMM(inst))
+ do_trap_or_bp(regs, 0, 0, "TGEIU");
+
+ MIPS_R2_STATS(traps);
+
+ break;
+ case tlti_op:
+ if ((long)regs->regs[rs] < MIPSInst_SIMM(inst))
+ do_trap_or_bp(regs, 0, 0, "TLTI");
+
+ MIPS_R2_STATS(traps);
+
+ break;
+ case tltiu_op:
+ if (regs->regs[rs] < MIPSInst_UIMM(inst))
+ do_trap_or_bp(regs, 0, 0, "TLTIU");
+
+ MIPS_R2_STATS(traps);
+
+ break;
+ case teqi_op:
+ if (regs->regs[rs] == MIPSInst_SIMM(inst))
+ do_trap_or_bp(regs, 0, 0, "TEQI");
+
+ MIPS_R2_STATS(traps);
+
+ break;
+ case tnei_op:
+ if (regs->regs[rs] != MIPSInst_SIMM(inst))
+ do_trap_or_bp(regs, 0, 0, "TNEI");
+
+ MIPS_R2_STATS(traps);
+
+ break;
+ case bltzl_op:
+ case bgezl_op:
+ case bltzall_op:
+ case bgezall_op:
+ if (delay_slot(regs)) {
+ err = SIGILL;
+ break;
+ }
+ regs->regs[31] = r31;
+ regs->cp0_epc = epc;
+ err = __compute_return_epc(regs);
+ if (err < 0)
+ return SIGEMT;
+ if (err != BRANCH_LIKELY_TAKEN)
+ break;
+ cpc = regs->cp0_epc;
+ nepc = epc + 4;
+ err = __get_user(nir, (u32 __user *)nepc);
+ if (err) {
+ err = SIGSEGV;
+ break;
+ }
+ /*
+ * This will probably be optimized away when
+ * CONFIG_DEBUG_FS is not enabled
+ */
+ switch (rt) {
+ case bltzl_op:
+ MIPS_R2BR_STATS(bltzl);
+ break;
+ case bgezl_op:
+ MIPS_R2BR_STATS(bgezl);
+ break;
+ case bltzall_op:
+ MIPS_R2BR_STATS(bltzall);
+ break;
+ case bgezall_op:
+ MIPS_R2BR_STATS(bgezall);
+ break;
+ }
+
+ switch (MIPSInst_OPCODE(nir)) {
+ case cop1_op:
+ case cop1x_op:
+ case lwc1_op:
+ case swc1_op:
+ regs->cp0_cause |= CAUSEF_BD;
+ goto fpu_emul;
+ }
+ if (nir) {
+ err = mipsr6_emul(regs, nir);
+ if (err > 0) {
+ err = mips_dsemul(regs, nir, epc, cpc);
+ if (err == SIGILL)
+ err = SIGEMT;
+ MIPS_R2_STATS(dsemul);
+ }
+ }
+ break;
+ case bltzal_op:
+ case bgezal_op:
+ if (delay_slot(regs)) {
+ err = SIGILL;
+ break;
+ }
+ regs->regs[31] = r31;
+ regs->cp0_epc = epc;
+ err = __compute_return_epc(regs);
+ if (err < 0)
+ return SIGEMT;
+ cpc = regs->cp0_epc;
+ nepc = epc + 4;
+ err = __get_user(nir, (u32 __user *)nepc);
+ if (err) {
+ err = SIGSEGV;
+ break;
+ }
+ /*
+ * This will probably be optimized away when
+ * CONFIG_DEBUG_FS is not enabled
+ */
+ switch (rt) {
+ case bltzal_op:
+ MIPS_R2BR_STATS(bltzal);
+ break;
+ case bgezal_op:
+ MIPS_R2BR_STATS(bgezal);
+ break;
+ }
+
+ switch (MIPSInst_OPCODE(nir)) {
+ case cop1_op:
+ case cop1x_op:
+ case lwc1_op:
+ case swc1_op:
+ regs->cp0_cause |= CAUSEF_BD;
+ goto fpu_emul;
+ }
+ if (nir) {
+ err = mipsr6_emul(regs, nir);
+ if (err > 0) {
+ err = mips_dsemul(regs, nir, epc, cpc);
+ if (err == SIGILL)
+ err = SIGEMT;
+ MIPS_R2_STATS(dsemul);
+ }
+ }
+ break;
+ default:
+ regs->regs[31] = r31;
+ regs->cp0_epc = epc;
+ err = SIGILL;
+ break;
+ }
+ break;
+
+ case blezl_op:
+ case bgtzl_op:
+ /*
+ * For BLEZL and BGTZL, rt field must be set to 0. If this
+ * is not the case, this may be an encoding of a MIPS R6
+ * instruction, so return to CPU execution if this occurs
+ */
+ if (MIPSInst_RT(inst)) {
+ err = SIGILL;
+ break;
+ }
+ /* fall through */
+ case beql_op:
+ case bnel_op:
+ if (delay_slot(regs)) {
+ err = SIGILL;
+ break;
+ }
+ regs->regs[31] = r31;
+ regs->cp0_epc = epc;
+ err = __compute_return_epc(regs);
+ if (err < 0)
+ return SIGEMT;
+ if (err != BRANCH_LIKELY_TAKEN)
+ break;
+ cpc = regs->cp0_epc;
+ nepc = epc + 4;
+ err = __get_user(nir, (u32 __user *)nepc);
+ if (err) {
+ err = SIGSEGV;
+ break;
+ }
+ /*
+ * This will probably be optimized away when
+ * CONFIG_DEBUG_FS is not enabled
+ */
+ switch (MIPSInst_OPCODE(inst)) {
+ case beql_op:
+ MIPS_R2BR_STATS(beql);
+ break;
+ case bnel_op:
+ MIPS_R2BR_STATS(bnel);
+ break;
+ case blezl_op:
+ MIPS_R2BR_STATS(blezl);
+ break;
+ case bgtzl_op:
+ MIPS_R2BR_STATS(bgtzl);
+ break;
+ }
+
+ switch (MIPSInst_OPCODE(nir)) {
+ case cop1_op:
+ case cop1x_op:
+ case lwc1_op:
+ case swc1_op:
+ regs->cp0_cause |= CAUSEF_BD;
+ goto fpu_emul;
+ }
+ if (nir) {
+ err = mipsr6_emul(regs, nir);
+ if (err > 0) {
+ err = mips_dsemul(regs, nir, epc, cpc);
+ if (err == SIGILL)
+ err = SIGEMT;
+ MIPS_R2_STATS(dsemul);
+ }
+ }
+ break;
+ case lwc1_op:
+ case swc1_op:
+ case cop1_op:
+ case cop1x_op:
+fpu_emul:
+ regs->regs[31] = r31;
+ regs->cp0_epc = epc;
+ if (!used_math()) { /* First time FPU user. */
+ preempt_disable();
+ err = init_fpu();
+ preempt_enable();
+ set_used_math();
+ }
+ lose_fpu(1); /* Save FPU state for the emulator. */
+
+ err = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 0,
+ &fault_addr);
+
+ /*
+ * We can't allow the emulated instruction to leave any
+ * enabled Cause bits set in $fcr31.
+ */
+ *fcr31 = res = mask_fcr31_x(current->thread.fpu.fcr31);
+ current->thread.fpu.fcr31 &= ~res;
+
+ /*
+ * this is a tricky issue - lose_fpu() uses LL/SC atomics
+ * if FPU is owned and effectively cancels user level LL/SC.
+ * So, it could be logical to don't restore FPU ownership here.
+ * But the sequence of multiple FPU instructions is much much
+ * more often than LL-FPU-SC and I prefer loop here until
+ * next scheduler cycle cancels FPU ownership
+ */
+ own_fpu(1); /* Restore FPU state. */
+
+ if (err)
+ current->thread.cp0_baduaddr = (unsigned long)fault_addr;
+
+ MIPS_R2_STATS(fpus);
+
+ break;
+
+ case lwl_op:
+ rt = regs->regs[MIPSInst_RT(inst)];
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (!access_ok(VERIFY_READ, (void __user *)vaddr, 4)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGSEGV;
+ break;
+ }
+ __asm__ __volatile__(
+ " .set push\n"
+ " .set reorder\n"
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ "1:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 24, 8\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ "2:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 16, 8\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ "3:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 8, 8\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ "4:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 0, 8\n"
+#else /* !CONFIG_CPU_LITTLE_ENDIAN */
+ "1:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 24, 8\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ "2:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 16, 8\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ "3:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 8, 8\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ "4:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 0, 8\n"
+#endif /* CONFIG_CPU_LITTLE_ENDIAN */
+ "9: sll %0, %0, 0\n"
+ "10:\n"
+ " .insn\n"
+ " .section .fixup,\"ax\"\n"
+ "8: li %3,%4\n"
+ " j 10b\n"
+ " .previous\n"
+ " .section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,8b\n"
+ STR(PTR) " 2b,8b\n"
+ STR(PTR) " 3b,8b\n"
+ STR(PTR) " 4b,8b\n"
+ " .previous\n"
+ " .set pop\n"
+ : "+&r"(rt), "=&r"(rs),
+ "+&r"(vaddr), "+&r"(err)
+ : "i"(SIGSEGV));
+
+ if (MIPSInst_RT(inst) && !err)
+ regs->regs[MIPSInst_RT(inst)] = rt;
+
+ MIPS_R2_STATS(loads);
+
+ break;
+
+ case lwr_op:
+ rt = regs->regs[MIPSInst_RT(inst)];
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (!access_ok(VERIFY_READ, (void __user *)vaddr, 4)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGSEGV;
+ break;
+ }
+ __asm__ __volatile__(
+ " .set push\n"
+ " .set reorder\n"
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ "1:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 0, 8\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ "2:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 8, 8\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ "3:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 16, 8\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ "4:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 24, 8\n"
+ " sll %0, %0, 0\n"
+#else /* !CONFIG_CPU_LITTLE_ENDIAN */
+ "1:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 0, 8\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ "2:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 8, 8\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ "3:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 16, 8\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ "4:" LB "%1, 0(%2)\n"
+ INS "%0, %1, 24, 8\n"
+ " sll %0, %0, 0\n"
+#endif /* CONFIG_CPU_LITTLE_ENDIAN */
+ "9:\n"
+ "10:\n"
+ " .insn\n"
+ " .section .fixup,\"ax\"\n"
+ "8: li %3,%4\n"
+ " j 10b\n"
+ " .previous\n"
+ " .section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,8b\n"
+ STR(PTR) " 2b,8b\n"
+ STR(PTR) " 3b,8b\n"
+ STR(PTR) " 4b,8b\n"
+ " .previous\n"
+ " .set pop\n"
+ : "+&r"(rt), "=&r"(rs),
+ "+&r"(vaddr), "+&r"(err)
+ : "i"(SIGSEGV));
+ if (MIPSInst_RT(inst) && !err)
+ regs->regs[MIPSInst_RT(inst)] = rt;
+
+ MIPS_R2_STATS(loads);
+
+ break;
+
+ case swl_op:
+ rt = regs->regs[MIPSInst_RT(inst)];
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (!access_ok(VERIFY_WRITE, (void __user *)vaddr, 4)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGSEGV;
+ break;
+ }
+ __asm__ __volatile__(
+ " .set push\n"
+ " .set reorder\n"
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ EXT "%1, %0, 24, 8\n"
+ "1:" SB "%1, 0(%2)\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ EXT "%1, %0, 16, 8\n"
+ "2:" SB "%1, 0(%2)\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ EXT "%1, %0, 8, 8\n"
+ "3:" SB "%1, 0(%2)\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ EXT "%1, %0, 0, 8\n"
+ "4:" SB "%1, 0(%2)\n"
+#else /* !CONFIG_CPU_LITTLE_ENDIAN */
+ EXT "%1, %0, 24, 8\n"
+ "1:" SB "%1, 0(%2)\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ EXT "%1, %0, 16, 8\n"
+ "2:" SB "%1, 0(%2)\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ EXT "%1, %0, 8, 8\n"
+ "3:" SB "%1, 0(%2)\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ EXT "%1, %0, 0, 8\n"
+ "4:" SB "%1, 0(%2)\n"
+#endif /* CONFIG_CPU_LITTLE_ENDIAN */
+ "9:\n"
+ " .insn\n"
+ " .section .fixup,\"ax\"\n"
+ "8: li %3,%4\n"
+ " j 9b\n"
+ " .previous\n"
+ " .section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,8b\n"
+ STR(PTR) " 2b,8b\n"
+ STR(PTR) " 3b,8b\n"
+ STR(PTR) " 4b,8b\n"
+ " .previous\n"
+ " .set pop\n"
+ : "+&r"(rt), "=&r"(rs),
+ "+&r"(vaddr), "+&r"(err)
+ : "i"(SIGSEGV)
+ : "memory");
+
+ MIPS_R2_STATS(stores);
+
+ break;
+
+ case swr_op:
+ rt = regs->regs[MIPSInst_RT(inst)];
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (!access_ok(VERIFY_WRITE, (void __user *)vaddr, 4)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGSEGV;
+ break;
+ }
+ __asm__ __volatile__(
+ " .set push\n"
+ " .set reorder\n"
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ EXT "%1, %0, 0, 8\n"
+ "1:" SB "%1, 0(%2)\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ EXT "%1, %0, 8, 8\n"
+ "2:" SB "%1, 0(%2)\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ EXT "%1, %0, 16, 8\n"
+ "3:" SB "%1, 0(%2)\n"
+ ADDIU "%2, %2, 1\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ EXT "%1, %0, 24, 8\n"
+ "4:" SB "%1, 0(%2)\n"
+#else /* !CONFIG_CPU_LITTLE_ENDIAN */
+ EXT "%1, %0, 0, 8\n"
+ "1:" SB "%1, 0(%2)\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ EXT "%1, %0, 8, 8\n"
+ "2:" SB "%1, 0(%2)\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ EXT "%1, %0, 16, 8\n"
+ "3:" SB "%1, 0(%2)\n"
+ " andi %1, %2, 0x3\n"
+ " beq $0, %1, 9f\n"
+ ADDIU "%2, %2, -1\n"
+ EXT "%1, %0, 24, 8\n"
+ "4:" SB "%1, 0(%2)\n"
+#endif /* CONFIG_CPU_LITTLE_ENDIAN */
+ "9:\n"
+ " .insn\n"
+ " .section .fixup,\"ax\"\n"
+ "8: li %3,%4\n"
+ " j 9b\n"
+ " .previous\n"
+ " .section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,8b\n"
+ STR(PTR) " 2b,8b\n"
+ STR(PTR) " 3b,8b\n"
+ STR(PTR) " 4b,8b\n"
+ " .previous\n"
+ " .set pop\n"
+ : "+&r"(rt), "=&r"(rs),
+ "+&r"(vaddr), "+&r"(err)
+ : "i"(SIGSEGV)
+ : "memory");
+
+ MIPS_R2_STATS(stores);
+
+ break;
+
+ case ldl_op:
+ if (IS_ENABLED(CONFIG_32BIT)) {
+ err = SIGILL;
+ break;
+ }
+
+ rt = regs->regs[MIPSInst_RT(inst)];
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (!access_ok(VERIFY_READ, (void __user *)vaddr, 8)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGSEGV;
+ break;
+ }
+ __asm__ __volatile__(
+ " .set push\n"
+ " .set reorder\n"
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ "1: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 56, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "2: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 48, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "3: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 40, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "4: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 32, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "5: lb %1, 0(%2)\n"
+ " dins %0, %1, 24, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "6: lb %1, 0(%2)\n"
+ " dins %0, %1, 16, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "7: lb %1, 0(%2)\n"
+ " dins %0, %1, 8, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "0: lb %1, 0(%2)\n"
+ " dins %0, %1, 0, 8\n"
+#else /* !CONFIG_CPU_LITTLE_ENDIAN */
+ "1: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 56, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "2: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 48, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "3: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 40, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "4: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 32, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "5: lb %1, 0(%2)\n"
+ " dins %0, %1, 24, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "6: lb %1, 0(%2)\n"
+ " dins %0, %1, 16, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "7: lb %1, 0(%2)\n"
+ " dins %0, %1, 8, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "0: lb %1, 0(%2)\n"
+ " dins %0, %1, 0, 8\n"
+#endif /* CONFIG_CPU_LITTLE_ENDIAN */
+ "9:\n"
+ " .insn\n"
+ " .section .fixup,\"ax\"\n"
+ "8: li %3,%4\n"
+ " j 9b\n"
+ " .previous\n"
+ " .section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,8b\n"
+ STR(PTR) " 2b,8b\n"
+ STR(PTR) " 3b,8b\n"
+ STR(PTR) " 4b,8b\n"
+ STR(PTR) " 5b,8b\n"
+ STR(PTR) " 6b,8b\n"
+ STR(PTR) " 7b,8b\n"
+ STR(PTR) " 0b,8b\n"
+ " .previous\n"
+ " .set pop\n"
+ : "+&r"(rt), "=&r"(rs),
+ "+&r"(vaddr), "+&r"(err)
+ : "i"(SIGSEGV));
+ if (MIPSInst_RT(inst) && !err)
+ regs->regs[MIPSInst_RT(inst)] = rt;
+
+ MIPS_R2_STATS(loads);
+ break;
+
+ case ldr_op:
+ if (IS_ENABLED(CONFIG_32BIT)) {
+ err = SIGILL;
+ break;
+ }
+
+ rt = regs->regs[MIPSInst_RT(inst)];
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (!access_ok(VERIFY_READ, (void __user *)vaddr, 8)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGSEGV;
+ break;
+ }
+ __asm__ __volatile__(
+ " .set push\n"
+ " .set reorder\n"
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ "1: lb %1, 0(%2)\n"
+ " dins %0, %1, 0, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "2: lb %1, 0(%2)\n"
+ " dins %0, %1, 8, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "3: lb %1, 0(%2)\n"
+ " dins %0, %1, 16, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "4: lb %1, 0(%2)\n"
+ " dins %0, %1, 24, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "5: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 32, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "6: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 40, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "7: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 48, 8\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ "0: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 56, 8\n"
+#else /* !CONFIG_CPU_LITTLE_ENDIAN */
+ "1: lb %1, 0(%2)\n"
+ " dins %0, %1, 0, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "2: lb %1, 0(%2)\n"
+ " dins %0, %1, 8, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "3: lb %1, 0(%2)\n"
+ " dins %0, %1, 16, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "4: lb %1, 0(%2)\n"
+ " dins %0, %1, 24, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "5: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 32, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "6: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 40, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "7: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 48, 8\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ "0: lb %1, 0(%2)\n"
+ " dinsu %0, %1, 56, 8\n"
+#endif /* CONFIG_CPU_LITTLE_ENDIAN */
+ "9:\n"
+ " .insn\n"
+ " .section .fixup,\"ax\"\n"
+ "8: li %3,%4\n"
+ " j 9b\n"
+ " .previous\n"
+ " .section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,8b\n"
+ STR(PTR) " 2b,8b\n"
+ STR(PTR) " 3b,8b\n"
+ STR(PTR) " 4b,8b\n"
+ STR(PTR) " 5b,8b\n"
+ STR(PTR) " 6b,8b\n"
+ STR(PTR) " 7b,8b\n"
+ STR(PTR) " 0b,8b\n"
+ " .previous\n"
+ " .set pop\n"
+ : "+&r"(rt), "=&r"(rs),
+ "+&r"(vaddr), "+&r"(err)
+ : "i"(SIGSEGV));
+ if (MIPSInst_RT(inst) && !err)
+ regs->regs[MIPSInst_RT(inst)] = rt;
+
+ MIPS_R2_STATS(loads);
+ break;
+
+ case sdl_op:
+ if (IS_ENABLED(CONFIG_32BIT)) {
+ err = SIGILL;
+ break;
+ }
+
+ rt = regs->regs[MIPSInst_RT(inst)];
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (!access_ok(VERIFY_WRITE, (void __user *)vaddr, 8)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGSEGV;
+ break;
+ }
+ __asm__ __volatile__(
+ " .set push\n"
+ " .set reorder\n"
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ " dextu %1, %0, 56, 8\n"
+ "1: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dextu %1, %0, 48, 8\n"
+ "2: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dextu %1, %0, 40, 8\n"
+ "3: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dextu %1, %0, 32, 8\n"
+ "4: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dext %1, %0, 24, 8\n"
+ "5: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dext %1, %0, 16, 8\n"
+ "6: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dext %1, %0, 8, 8\n"
+ "7: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dext %1, %0, 0, 8\n"
+ "0: sb %1, 0(%2)\n"
+#else /* !CONFIG_CPU_LITTLE_ENDIAN */
+ " dextu %1, %0, 56, 8\n"
+ "1: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dextu %1, %0, 48, 8\n"
+ "2: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dextu %1, %0, 40, 8\n"
+ "3: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dextu %1, %0, 32, 8\n"
+ "4: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dext %1, %0, 24, 8\n"
+ "5: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dext %1, %0, 16, 8\n"
+ "6: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dext %1, %0, 8, 8\n"
+ "7: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dext %1, %0, 0, 8\n"
+ "0: sb %1, 0(%2)\n"
+#endif /* CONFIG_CPU_LITTLE_ENDIAN */
+ "9:\n"
+ " .insn\n"
+ " .section .fixup,\"ax\"\n"
+ "8: li %3,%4\n"
+ " j 9b\n"
+ " .previous\n"
+ " .section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,8b\n"
+ STR(PTR) " 2b,8b\n"
+ STR(PTR) " 3b,8b\n"
+ STR(PTR) " 4b,8b\n"
+ STR(PTR) " 5b,8b\n"
+ STR(PTR) " 6b,8b\n"
+ STR(PTR) " 7b,8b\n"
+ STR(PTR) " 0b,8b\n"
+ " .previous\n"
+ " .set pop\n"
+ : "+&r"(rt), "=&r"(rs),
+ "+&r"(vaddr), "+&r"(err)
+ : "i"(SIGSEGV)
+ : "memory");
+
+ MIPS_R2_STATS(stores);
+ break;
+
+ case sdr_op:
+ if (IS_ENABLED(CONFIG_32BIT)) {
+ err = SIGILL;
+ break;
+ }
+
+ rt = regs->regs[MIPSInst_RT(inst)];
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (!access_ok(VERIFY_WRITE, (void __user *)vaddr, 8)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGSEGV;
+ break;
+ }
+ __asm__ __volatile__(
+ " .set push\n"
+ " .set reorder\n"
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ " dext %1, %0, 0, 8\n"
+ "1: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dext %1, %0, 8, 8\n"
+ "2: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dext %1, %0, 16, 8\n"
+ "3: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dext %1, %0, 24, 8\n"
+ "4: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dextu %1, %0, 32, 8\n"
+ "5: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dextu %1, %0, 40, 8\n"
+ "6: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dextu %1, %0, 48, 8\n"
+ "7: sb %1, 0(%2)\n"
+ " daddiu %2, %2, 1\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " dextu %1, %0, 56, 8\n"
+ "0: sb %1, 0(%2)\n"
+#else /* !CONFIG_CPU_LITTLE_ENDIAN */
+ " dext %1, %0, 0, 8\n"
+ "1: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dext %1, %0, 8, 8\n"
+ "2: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dext %1, %0, 16, 8\n"
+ "3: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dext %1, %0, 24, 8\n"
+ "4: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dextu %1, %0, 32, 8\n"
+ "5: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dextu %1, %0, 40, 8\n"
+ "6: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dextu %1, %0, 48, 8\n"
+ "7: sb %1, 0(%2)\n"
+ " andi %1, %2, 0x7\n"
+ " beq $0, %1, 9f\n"
+ " daddiu %2, %2, -1\n"
+ " dextu %1, %0, 56, 8\n"
+ "0: sb %1, 0(%2)\n"
+#endif /* CONFIG_CPU_LITTLE_ENDIAN */
+ "9:\n"
+ " .insn\n"
+ " .section .fixup,\"ax\"\n"
+ "8: li %3,%4\n"
+ " j 9b\n"
+ " .previous\n"
+ " .section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,8b\n"
+ STR(PTR) " 2b,8b\n"
+ STR(PTR) " 3b,8b\n"
+ STR(PTR) " 4b,8b\n"
+ STR(PTR) " 5b,8b\n"
+ STR(PTR) " 6b,8b\n"
+ STR(PTR) " 7b,8b\n"
+ STR(PTR) " 0b,8b\n"
+ " .previous\n"
+ " .set pop\n"
+ : "+&r"(rt), "=&r"(rs),
+ "+&r"(vaddr), "+&r"(err)
+ : "i"(SIGSEGV)
+ : "memory");
+
+ MIPS_R2_STATS(stores);
+
+ break;
+ case ll_op:
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (vaddr & 0x3) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGBUS;
+ break;
+ }
+ if (!access_ok(VERIFY_READ, (void __user *)vaddr, 4)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGBUS;
+ break;
+ }
+
+ if (!cpu_has_rw_llb) {
+ /*
+ * An LL/SC block can't be safely emulated without
+ * a Config5/LLB availability. So it's probably time to
+ * kill our process before things get any worse. This is
+ * because Config5/LLB allows us to use ERETNC so that
+ * the LLAddr/LLB bit is not cleared when we return from
+ * an exception. MIPS R2 LL/SC instructions trap with an
+ * RI exception so once we emulate them here, we return
+ * back to userland with ERETNC. That preserves the
+ * LLAddr/LLB so the subsequent SC instruction will
+ * succeed preserving the atomic semantics of the LL/SC
+ * block. Without that, there is no safe way to emulate
+ * an LL/SC block in MIPSR2 userland.
+ */
+ pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
+ err = SIGKILL;
+ break;
+ }
+
+ __asm__ __volatile__(
+ "1:\n"
+ "ll %0, 0(%2)\n"
+ "2:\n"
+ ".insn\n"
+ ".section .fixup,\"ax\"\n"
+ "3:\n"
+ "li %1, %3\n"
+ "j 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,3b\n"
+ ".previous\n"
+ : "=&r"(res), "+&r"(err)
+ : "r"(vaddr), "i"(SIGSEGV)
+ : "memory");
+
+ if (MIPSInst_RT(inst) && !err)
+ regs->regs[MIPSInst_RT(inst)] = res;
+ MIPS_R2_STATS(llsc);
+
+ break;
+
+ case sc_op:
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (vaddr & 0x3) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGBUS;
+ break;
+ }
+ if (!access_ok(VERIFY_WRITE, (void __user *)vaddr, 4)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGBUS;
+ break;
+ }
+
+ if (!cpu_has_rw_llb) {
+ /*
+ * An LL/SC block can't be safely emulated without
+ * a Config5/LLB availability. So it's probably time to
+ * kill our process before things get any worse. This is
+ * because Config5/LLB allows us to use ERETNC so that
+ * the LLAddr/LLB bit is not cleared when we return from
+ * an exception. MIPS R2 LL/SC instructions trap with an
+ * RI exception so once we emulate them here, we return
+ * back to userland with ERETNC. That preserves the
+ * LLAddr/LLB so the subsequent SC instruction will
+ * succeed preserving the atomic semantics of the LL/SC
+ * block. Without that, there is no safe way to emulate
+ * an LL/SC block in MIPSR2 userland.
+ */
+ pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
+ err = SIGKILL;
+ break;
+ }
+
+ res = regs->regs[MIPSInst_RT(inst)];
+
+ __asm__ __volatile__(
+ "1:\n"
+ "sc %0, 0(%2)\n"
+ "2:\n"
+ ".insn\n"
+ ".section .fixup,\"ax\"\n"
+ "3:\n"
+ "li %1, %3\n"
+ "j 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,3b\n"
+ ".previous\n"
+ : "+&r"(res), "+&r"(err)
+ : "r"(vaddr), "i"(SIGSEGV));
+
+ if (MIPSInst_RT(inst) && !err)
+ regs->regs[MIPSInst_RT(inst)] = res;
+
+ MIPS_R2_STATS(llsc);
+
+ break;
+
+ case lld_op:
+ if (IS_ENABLED(CONFIG_32BIT)) {
+ err = SIGILL;
+ break;
+ }
+
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (vaddr & 0x7) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGBUS;
+ break;
+ }
+ if (!access_ok(VERIFY_READ, (void __user *)vaddr, 8)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGBUS;
+ break;
+ }
+
+ if (!cpu_has_rw_llb) {
+ /*
+ * An LL/SC block can't be safely emulated without
+ * a Config5/LLB availability. So it's probably time to
+ * kill our process before things get any worse. This is
+ * because Config5/LLB allows us to use ERETNC so that
+ * the LLAddr/LLB bit is not cleared when we return from
+ * an exception. MIPS R2 LL/SC instructions trap with an
+ * RI exception so once we emulate them here, we return
+ * back to userland with ERETNC. That preserves the
+ * LLAddr/LLB so the subsequent SC instruction will
+ * succeed preserving the atomic semantics of the LL/SC
+ * block. Without that, there is no safe way to emulate
+ * an LL/SC block in MIPSR2 userland.
+ */
+ pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
+ err = SIGKILL;
+ break;
+ }
+
+ __asm__ __volatile__(
+ "1:\n"
+ "lld %0, 0(%2)\n"
+ "2:\n"
+ ".insn\n"
+ ".section .fixup,\"ax\"\n"
+ "3:\n"
+ "li %1, %3\n"
+ "j 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,3b\n"
+ ".previous\n"
+ : "=&r"(res), "+&r"(err)
+ : "r"(vaddr), "i"(SIGSEGV)
+ : "memory");
+ if (MIPSInst_RT(inst) && !err)
+ regs->regs[MIPSInst_RT(inst)] = res;
+
+ MIPS_R2_STATS(llsc);
+
+ break;
+
+ case scd_op:
+ if (IS_ENABLED(CONFIG_32BIT)) {
+ err = SIGILL;
+ break;
+ }
+
+ vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
+ if (vaddr & 0x7) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGBUS;
+ break;
+ }
+ if (!access_ok(VERIFY_WRITE, (void __user *)vaddr, 8)) {
+ current->thread.cp0_baduaddr = vaddr;
+ err = SIGBUS;
+ break;
+ }
+
+ if (!cpu_has_rw_llb) {
+ /*
+ * An LL/SC block can't be safely emulated without
+ * a Config5/LLB availability. So it's probably time to
+ * kill our process before things get any worse. This is
+ * because Config5/LLB allows us to use ERETNC so that
+ * the LLAddr/LLB bit is not cleared when we return from
+ * an exception. MIPS R2 LL/SC instructions trap with an
+ * RI exception so once we emulate them here, we return
+ * back to userland with ERETNC. That preserves the
+ * LLAddr/LLB so the subsequent SC instruction will
+ * succeed preserving the atomic semantics of the LL/SC
+ * block. Without that, there is no safe way to emulate
+ * an LL/SC block in MIPSR2 userland.
+ */
+ pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
+ err = SIGKILL;
+ break;
+ }
+
+ res = regs->regs[MIPSInst_RT(inst)];
+
+ __asm__ __volatile__(
+ "1:\n"
+ "scd %0, 0(%2)\n"
+ "2:\n"
+ ".insn\n"
+ ".section .fixup,\"ax\"\n"
+ "3:\n"
+ "li %1, %3\n"
+ "j 2b\n"
+ ".previous\n"
+ ".section __ex_table,\"a\"\n"
+ STR(PTR) " 1b,3b\n"
+ ".previous\n"
+ : "+&r"(res), "+&r"(err)
+ : "r"(vaddr), "i"(SIGSEGV));
+
+ if (MIPSInst_RT(inst) && !err)
+ regs->regs[MIPSInst_RT(inst)] = res;
+
+ MIPS_R2_STATS(llsc);
+
+ break;
+ case pref_op:
+ /* skip it */
+ break;
+ default:
+ err = SIGILL;
+ }
+
+ /*
+ * Let's not return to userland just yet. It's costly and
+ * it's likely we have more R2 instructions to emulate
+ */
+ if (!err && (pass++ < MIPS_R2_EMUL_TOTAL_PASS)) {
+ regs->cp0_cause &= ~CAUSEF_BD;
+ err = get_user(inst, (u32 __user *)regs->cp0_epc);
+ if (!err)
+ goto repeat;
+
+ if (err < 0)
+ err = SIGSEGV;
+ }
+
+ if (err && (err != SIGEMT)) {
+ regs->regs[31] = r31;
+ regs->cp0_epc = epc;
+ }
+
+ /* Likely a MIPS R6 compatible instruction */
+ if (pass && (err == SIGILL))
+ err = 0;
+
+ return err;
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+static int mipsr2_stats_show(struct seq_file *s, void *unused)
+{
+
+ seq_printf(s, "Instruction\tTotal\tBDslot\n------------------------------\n");
+ seq_printf(s, "movs\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.movs),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.movs));
+ seq_printf(s, "hilo\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.hilo),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.hilo));
+ seq_printf(s, "muls\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.muls),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.muls));
+ seq_printf(s, "divs\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.divs),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.divs));
+ seq_printf(s, "dsps\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.dsps),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.dsps));
+ seq_printf(s, "bops\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.bops),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.bops));
+ seq_printf(s, "traps\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.traps),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.traps));
+ seq_printf(s, "fpus\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.fpus),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.fpus));
+ seq_printf(s, "loads\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.loads),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.loads));
+ seq_printf(s, "stores\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.stores),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.stores));
+ seq_printf(s, "llsc\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.llsc),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.llsc));
+ seq_printf(s, "dsemul\t\t%ld\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2emustats.dsemul),
+ (unsigned long)__this_cpu_read(mipsr2bdemustats.dsemul));
+ seq_printf(s, "jr\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.jrs));
+ seq_printf(s, "bltzl\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.bltzl));
+ seq_printf(s, "bgezl\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.bgezl));
+ seq_printf(s, "bltzll\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.bltzll));
+ seq_printf(s, "bgezll\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.bgezll));
+ seq_printf(s, "bltzal\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.bltzal));
+ seq_printf(s, "bgezal\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.bgezal));
+ seq_printf(s, "beql\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.beql));
+ seq_printf(s, "bnel\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.bnel));
+ seq_printf(s, "blezl\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.blezl));
+ seq_printf(s, "bgtzl\t\t%ld\n",
+ (unsigned long)__this_cpu_read(mipsr2bremustats.bgtzl));
+
+ return 0;
+}
+
+static int mipsr2_stats_clear_show(struct seq_file *s, void *unused)
+{
+ mipsr2_stats_show(s, unused);
+
+ __this_cpu_write((mipsr2emustats).movs, 0);
+ __this_cpu_write((mipsr2bdemustats).movs, 0);
+ __this_cpu_write((mipsr2emustats).hilo, 0);
+ __this_cpu_write((mipsr2bdemustats).hilo, 0);
+ __this_cpu_write((mipsr2emustats).muls, 0);
+ __this_cpu_write((mipsr2bdemustats).muls, 0);
+ __this_cpu_write((mipsr2emustats).divs, 0);
+ __this_cpu_write((mipsr2bdemustats).divs, 0);
+ __this_cpu_write((mipsr2emustats).dsps, 0);
+ __this_cpu_write((mipsr2bdemustats).dsps, 0);
+ __this_cpu_write((mipsr2emustats).bops, 0);
+ __this_cpu_write((mipsr2bdemustats).bops, 0);
+ __this_cpu_write((mipsr2emustats).traps, 0);
+ __this_cpu_write((mipsr2bdemustats).traps, 0);
+ __this_cpu_write((mipsr2emustats).fpus, 0);
+ __this_cpu_write((mipsr2bdemustats).fpus, 0);
+ __this_cpu_write((mipsr2emustats).loads, 0);
+ __this_cpu_write((mipsr2bdemustats).loads, 0);
+ __this_cpu_write((mipsr2emustats).stores, 0);
+ __this_cpu_write((mipsr2bdemustats).stores, 0);
+ __this_cpu_write((mipsr2emustats).llsc, 0);
+ __this_cpu_write((mipsr2bdemustats).llsc, 0);
+ __this_cpu_write((mipsr2emustats).dsemul, 0);
+ __this_cpu_write((mipsr2bdemustats).dsemul, 0);
+ __this_cpu_write((mipsr2bremustats).jrs, 0);
+ __this_cpu_write((mipsr2bremustats).bltzl, 0);
+ __this_cpu_write((mipsr2bremustats).bgezl, 0);
+ __this_cpu_write((mipsr2bremustats).bltzll, 0);
+ __this_cpu_write((mipsr2bremustats).bgezll, 0);
+ __this_cpu_write((mipsr2bremustats).bltzall, 0);
+ __this_cpu_write((mipsr2bremustats).bgezall, 0);
+ __this_cpu_write((mipsr2bremustats).bltzal, 0);
+ __this_cpu_write((mipsr2bremustats).bgezal, 0);
+ __this_cpu_write((mipsr2bremustats).beql, 0);
+ __this_cpu_write((mipsr2bremustats).bnel, 0);
+ __this_cpu_write((mipsr2bremustats).blezl, 0);
+ __this_cpu_write((mipsr2bremustats).bgtzl, 0);
+
+ return 0;
+}
+
+static int mipsr2_stats_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, mipsr2_stats_show, inode->i_private);
+}
+
+static int mipsr2_stats_clear_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, mipsr2_stats_clear_show, inode->i_private);
+}
+
+static const struct file_operations mipsr2_emul_fops = {
+ .open = mipsr2_stats_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static const struct file_operations mipsr2_clear_fops = {
+ .open = mipsr2_stats_clear_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+
+static int __init mipsr2_init_debugfs(void)
+{
+ struct dentry *mipsr2_emul;
+
+ if (!mips_debugfs_dir)
+ return -ENODEV;
+
+ mipsr2_emul = debugfs_create_file("r2_emul_stats", S_IRUGO,
+ mips_debugfs_dir, NULL,
+ &mipsr2_emul_fops);
+ if (!mipsr2_emul)
+ return -ENOMEM;
+
+ mipsr2_emul = debugfs_create_file("r2_emul_stats_clear", S_IRUGO,
+ mips_debugfs_dir, NULL,
+ &mipsr2_clear_fops);
+ if (!mipsr2_emul)
+ return -ENOMEM;
+
+ return 0;
+}
+
+device_initcall(mipsr2_init_debugfs);
+
+#endif /* CONFIG_DEBUG_FS */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 03:35:34 +0000