arch/riscv/kernel/traps_misaligned.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2020 Western Digital Corporation or its affiliates.
  */
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/irq.h>

 #include <asm/processor.h>
 #include <asm/ptrace.h>
 #include <asm/csr.h>

 #define INSN_MATCH_LB			0x3
 #define INSN_MASK_LB			0x707f
 #define INSN_MATCH_LH			0x1003
 #define INSN_MASK_LH			0x707f
 #define INSN_MATCH_LW			0x2003
 #define INSN_MASK_LW			0x707f
 #define INSN_MATCH_LD			0x3003
 #define INSN_MASK_LD			0x707f
 #define INSN_MATCH_LBU			0x4003
 #define INSN_MASK_LBU			0x707f
 #define INSN_MATCH_LHU			0x5003
 #define INSN_MASK_LHU			0x707f
 #define INSN_MATCH_LWU			0x6003
 #define INSN_MASK_LWU			0x707f
 #define INSN_MATCH_SB			0x23
 #define INSN_MASK_SB			0x707f
 #define INSN_MATCH_SH			0x1023
 #define INSN_MASK_SH			0x707f
 #define INSN_MATCH_SW			0x2023
 #define INSN_MASK_SW			0x707f
 #define INSN_MATCH_SD			0x3023
 #define INSN_MASK_SD			0x707f

 #define INSN_MATCH_FLW			0x2007
 #define INSN_MASK_FLW			0x707f
 #define INSN_MATCH_FLD			0x3007
 #define INSN_MASK_FLD			0x707f
 #define INSN_MATCH_FLQ			0x4007
 #define INSN_MASK_FLQ			0x707f
 #define INSN_MATCH_FSW			0x2027
 #define INSN_MASK_FSW			0x707f
 #define INSN_MATCH_FSD			0x3027
 #define INSN_MASK_FSD			0x707f
 #define INSN_MATCH_FSQ			0x4027
 #define INSN_MASK_FSQ			0x707f

 #define INSN_MATCH_C_LD			0x6000
 #define INSN_MASK_C_LD			0xe003
 #define INSN_MATCH_C_SD			0xe000
 #define INSN_MASK_C_SD			0xe003
 #define INSN_MATCH_C_LW			0x4000
 #define INSN_MASK_C_LW			0xe003
 #define INSN_MATCH_C_SW			0xc000
 #define INSN_MASK_C_SW			0xe003
 #define INSN_MATCH_C_LDSP		0x6002
 #define INSN_MASK_C_LDSP		0xe003
 #define INSN_MATCH_C_SDSP		0xe002
 #define INSN_MASK_C_SDSP		0xe003
 #define INSN_MATCH_C_LWSP		0x4002
 #define INSN_MASK_C_LWSP		0xe003
 #define INSN_MATCH_C_SWSP		0xc002
 #define INSN_MASK_C_SWSP		0xe003

 #define INSN_MATCH_C_FLD		0x2000
 #define INSN_MASK_C_FLD			0xe003
 #define INSN_MATCH_C_FLW		0x6000
 #define INSN_MASK_C_FLW			0xe003
 #define INSN_MATCH_C_FSD		0xa000
 #define INSN_MASK_C_FSD			0xe003
 #define INSN_MATCH_C_FSW		0xe000
 #define INSN_MASK_C_FSW			0xe003
 #define INSN_MATCH_C_FLDSP		0x2002
 #define INSN_MASK_C_FLDSP		0xe003
 #define INSN_MATCH_C_FSDSP		0xa002
 #define INSN_MASK_C_FSDSP		0xe003
 #define INSN_MATCH_C_FLWSP		0x6002
 #define INSN_MASK_C_FLWSP		0xe003
 #define INSN_MATCH_C_FSWSP		0xe002
 #define INSN_MASK_C_FSWSP		0xe003

 #define INSN_LEN(insn)			((((insn) & 0x3) < 0x3) ? 2 : 4)

 #if defined(CONFIG_64BIT)
 #define LOG_REGBYTES			3
 #define XLEN				64
 #else
 #define LOG_REGBYTES			2
 #define XLEN				32
 #endif
 #define REGBYTES			(1 << LOG_REGBYTES)
 #define XLEN_MINUS_16			((XLEN) - 16)

 #define SH_RD				7
 #define SH_RS1				15
 #define SH_RS2				20
 #define SH_RS2C				2

 #define RV_X(x, s, n)			(((x) >> (s)) & ((1 << (n)) - 1))
 #define RVC_LW_IMM(x)			((RV_X(x, 6, 1) << 2) | \
 					 (RV_X(x, 10, 3) << 3) | \
 					 (RV_X(x, 5, 1) << 6))
 #define RVC_LD_IMM(x)			((RV_X(x, 10, 3) << 3) | \
 					 (RV_X(x, 5, 2) << 6))
 #define RVC_LWSP_IMM(x)			((RV_X(x, 4, 3) << 2) | \
 					 (RV_X(x, 12, 1) << 5) | \
 					 (RV_X(x, 2, 2) << 6))
 #define RVC_LDSP_IMM(x)			((RV_X(x, 5, 2) << 3) | \
 					 (RV_X(x, 12, 1) << 5) | \
 					 (RV_X(x, 2, 3) << 6))
 #define RVC_SWSP_IMM(x)			((RV_X(x, 9, 4) << 2) | \
 					 (RV_X(x, 7, 2) << 6))
 #define RVC_SDSP_IMM(x)			((RV_X(x, 10, 3) << 3) | \
 					 (RV_X(x, 7, 3) << 6))
 #define RVC_RS1S(insn)			(8 + RV_X(insn, SH_RD, 3))
 #define RVC_RS2S(insn)			(8 + RV_X(insn, SH_RS2C, 3))
 #define RVC_RS2(insn)			RV_X(insn, SH_RS2C, 5)

 #define SHIFT_RIGHT(x, y)		\
 	((y) < 0 ? ((x) << -(y)) : ((x) >> (y)))

 #define REG_MASK			\
 	((1 << (5 + LOG_REGBYTES)) - (1 << LOG_REGBYTES))

 #define REG_OFFSET(insn, pos)		\
 	(SHIFT_RIGHT((insn), (pos) - LOG_REGBYTES) & REG_MASK)

 #define REG_PTR(insn, pos, regs)	\
 	(ulong *)((ulong)(regs) + REG_OFFSET(insn, pos))

 #define GET_RM(insn)			(((insn) >> 12) & 7)

 #define GET_RS1(insn, regs)		(*REG_PTR(insn, SH_RS1, regs))
 #define GET_RS2(insn, regs)		(*REG_PTR(insn, SH_RS2, regs))
 #define GET_RS1S(insn, regs)		(*REG_PTR(RVC_RS1S(insn), 0, regs))
 #define GET_RS2S(insn, regs)		(*REG_PTR(RVC_RS2S(insn), 0, regs))
 #define GET_RS2C(insn, regs)		(*REG_PTR(insn, SH_RS2C, regs))
 #define GET_SP(regs)			(*REG_PTR(2, 0, regs))
 #define SET_RD(insn, regs, val)		(*REG_PTR(insn, SH_RD, regs) = (val))
 #define IMM_I(insn)			((s32)(insn) >> 20)
 #define IMM_S(insn)			(((s32)(insn) >> 25 << 5) | \
 					 (s32)(((insn) >> 7) & 0x1f))
 #define MASK_FUNCT3			0x7000

 #define GET_PRECISION(insn) (((insn) >> 25) & 3)
 #define GET_RM(insn) (((insn) >> 12) & 7)
 #define PRECISION_S 0
 #define PRECISION_D 1

 #define STR(x) XSTR(x)
 #define XSTR(x) #x

 #define DECLARE_UNPRIVILEGED_LOAD_FUNCTION(type, insn)			\
 static inline type load_##type(const type *addr)			\
 {									\
 	type val;							\
 	asm (#insn " %0, %1"						\
 	: "=&r" (val) : "m" (*addr));					\
 	return val;							\
 }

 #define DECLARE_UNPRIVILEGED_STORE_FUNCTION(type, insn)			\
 static inline void store_##type(type *addr, type val)			\
 {									\
 	asm volatile (#insn " %0, %1\n"					\
 	: : "r" (val), "m" (*addr));					\
 }

 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u8, lbu)
 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u16, lhu)
 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(s8, lb)
 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(s16, lh)
 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(s32, lw)
 DECLARE_UNPRIVILEGED_STORE_FUNCTION(u8, sb)
 DECLARE_UNPRIVILEGED_STORE_FUNCTION(u16, sh)
 DECLARE_UNPRIVILEGED_STORE_FUNCTION(u32, sw)
 #if defined(CONFIG_64BIT)
 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u32, lwu)
 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u64, ld)
 DECLARE_UNPRIVILEGED_STORE_FUNCTION(u64, sd)
 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(ulong, ld)
 #else
 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u32, lw)
 DECLARE_UNPRIVILEGED_LOAD_FUNCTION(ulong, lw)

 static inline u64 load_u64(const u64 *addr)
 {
 	return load_u32((u32 *)addr)
 		+ ((u64)load_u32((u32 *)addr + 1) << 32);
 }

 static inline void store_u64(u64 *addr, u64 val)
 {
 	store_u32((u32 *)addr, val);
 	store_u32((u32 *)addr + 1, val >> 32);
 }
 #endif

 static inline ulong get_insn(ulong mepc)
 {
 	register ulong __mepc asm ("a2") = mepc;
 	ulong val, rvc_mask = 3, tmp;

 	asm ("and %[tmp], %[addr], 2\n"
 		"bnez %[tmp], 1f\n"
 #if defined(CONFIG_64BIT)
 		STR(LWU) " %[insn], (%[addr])\n"
 #else
 		STR(LW) " %[insn], (%[addr])\n"
 #endif
 		"and %[tmp], %[insn], %[rvc_mask]\n"
 		"beq %[tmp], %[rvc_mask], 2f\n"
 		"sll %[insn], %[insn], %[xlen_minus_16]\n"
 		"srl %[insn], %[insn], %[xlen_minus_16]\n"
 		"j 2f\n"
 		"1:\n"
 		"lhu %[insn], (%[addr])\n"
 		"and %[tmp], %[insn], %[rvc_mask]\n"
 		"bne %[tmp], %[rvc_mask], 2f\n"
 		"lhu %[tmp], 2(%[addr])\n"
 		"sll %[tmp], %[tmp], 16\n"
 		"add %[insn], %[insn], %[tmp]\n"
 		"2:"
 	: [insn] "=&r" (val), [tmp] "=&r" (tmp)
 	: [addr] "r" (__mepc), [rvc_mask] "r" (rvc_mask),
 	  [xlen_minus_16] "i" (XLEN_MINUS_16));

 	return val;
 }

 union reg_data {
 	u8 data_bytes[8];
 	ulong data_ulong;
 	u64 data_u64;
 };

 int handle_misaligned_load(struct pt_regs *regs)
 {
 	union reg_data val;
 	unsigned long epc = regs->epc;
 	unsigned long insn = get_insn(epc);
 	unsigned long addr = csr_read(mtval);
 	int i, fp = 0, shift = 0, len = 0;

 	regs->epc = 0;

 	if ((insn & INSN_MASK_LW) == INSN_MATCH_LW) {
 		len = 4;
 		shift = 8 * (sizeof(unsigned long) - len);
 #if defined(CONFIG_64BIT)
 	} else if ((insn & INSN_MASK_LD) == INSN_MATCH_LD) {
 		len = 8;
 		shift = 8 * (sizeof(unsigned long) - len);
 	} else if ((insn & INSN_MASK_LWU) == INSN_MATCH_LWU) {
 		len = 4;
 #endif
 	} else if ((insn & INSN_MASK_FLD) == INSN_MATCH_FLD) {
 		fp = 1;
 		len = 8;
 	} else if ((insn & INSN_MASK_FLW) == INSN_MATCH_FLW) {
 		fp = 1;
 		len = 4;
 	} else if ((insn & INSN_MASK_LH) == INSN_MATCH_LH) {
 		len = 2;
 		shift = 8 * (sizeof(unsigned long) - len);
 	} else if ((insn & INSN_MASK_LHU) == INSN_MATCH_LHU) {
 		len = 2;
 #if defined(CONFIG_64BIT)
 	} else if ((insn & INSN_MASK_C_LD) == INSN_MATCH_C_LD) {
 		len = 8;
 		shift = 8 * (sizeof(unsigned long) - len);
 		insn = RVC_RS2S(insn) << SH_RD;
 	} else if ((insn & INSN_MASK_C_LDSP) == INSN_MATCH_C_LDSP &&
 		   ((insn >> SH_RD) & 0x1f)) {
 		len = 8;
 		shift = 8 * (sizeof(unsigned long) - len);
 #endif
 	} else if ((insn & INSN_MASK_C_LW) == INSN_MATCH_C_LW) {
 		len = 4;
 		shift = 8 * (sizeof(unsigned long) - len);
 		insn = RVC_RS2S(insn) << SH_RD;
 	} else if ((insn & INSN_MASK_C_LWSP) == INSN_MATCH_C_LWSP &&
 		   ((insn >> SH_RD) & 0x1f)) {
 		len = 4;
 		shift = 8 * (sizeof(unsigned long) - len);
 	} else if ((insn & INSN_MASK_C_FLD) == INSN_MATCH_C_FLD) {
 		fp = 1;
 		len = 8;
 		insn = RVC_RS2S(insn) << SH_RD;
 	} else if ((insn & INSN_MASK_C_FLDSP) == INSN_MATCH_C_FLDSP) {
 		fp = 1;
 		len = 8;
 #if defined(CONFIG_32BIT)
 	} else if ((insn & INSN_MASK_C_FLW) == INSN_MATCH_C_FLW) {
 		fp = 1;
 		len = 4;
 		insn = RVC_RS2S(insn) << SH_RD;
 	} else if ((insn & INSN_MASK_C_FLWSP) == INSN_MATCH_C_FLWSP) {
 		fp = 1;
 		len = 4;
 #endif
 	} else {
 		regs->epc = epc;
 		return -1;
 	}

 	val.data_u64 = 0;
 	for (i = 0; i < len; i++)
 		val.data_bytes[i] = load_u8((void *)(addr + i));

 	if (fp)
 		return -1;
 	SET_RD(insn, regs, val.data_ulong << shift >> shift);

 	regs->epc = epc + INSN_LEN(insn);

 	return 0;
 }

 int handle_misaligned_store(struct pt_regs *regs)
 {
 	union reg_data val;
 	unsigned long epc = regs->epc;
 	unsigned long insn = get_insn(epc);
 	unsigned long addr = csr_read(mtval);
 	int i, len = 0;

 	regs->epc = 0;

 	val.data_ulong = GET_RS2(insn, regs);

 	if ((insn & INSN_MASK_SW) == INSN_MATCH_SW) {
 		len = 4;
 #if defined(CONFIG_64BIT)
 	} else if ((insn & INSN_MASK_SD) == INSN_MATCH_SD) {
 		len = 8;
 #endif
 	} else if ((insn & INSN_MASK_SH) == INSN_MATCH_SH) {
 		len = 2;
 #if defined(CONFIG_64BIT)
 	} else if ((insn & INSN_MASK_C_SD) == INSN_MATCH_C_SD) {
 		len = 8;
 		val.data_ulong = GET_RS2S(insn, regs);
 	} else if ((insn & INSN_MASK_C_SDSP) == INSN_MATCH_C_SDSP &&
 		   ((insn >> SH_RD) & 0x1f)) {
 		len = 8;
 		val.data_ulong = GET_RS2C(insn, regs);
 #endif
 	} else if ((insn & INSN_MASK_C_SW) == INSN_MATCH_C_SW) {
 		len = 4;
 		val.data_ulong = GET_RS2S(insn, regs);
 	} else if ((insn & INSN_MASK_C_SWSP) == INSN_MATCH_C_SWSP &&
 		   ((insn >> SH_RD) & 0x1f)) {
 		len = 4;
 		val.data_ulong = GET_RS2C(insn, regs);
 	} else {
 		regs->epc = epc;
 		return -1;
 	}

 	for (i = 0; i < len; i++)
 		store_u8((void *)(addr + i), val.data_bytes[i]);

 	regs->epc = epc + INSN_LEN(insn);

 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Copyright (C) 2020 Western Digital Corporation or its affiliates.
	*/
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/mm.h>
	#include <linux/module.h>
	#include <linux/irq.h>

	#include <asm/processor.h>
	#include <asm/ptrace.h>
	#include <asm/csr.h>

	#define INSN_MATCH_LB 0x3
	#define INSN_MASK_LB 0x707f
	#define INSN_MATCH_LH 0x1003
	#define INSN_MASK_LH 0x707f
	#define INSN_MATCH_LW 0x2003
	#define INSN_MASK_LW 0x707f
	#define INSN_MATCH_LD 0x3003
	#define INSN_MASK_LD 0x707f
	#define INSN_MATCH_LBU 0x4003
	#define INSN_MASK_LBU 0x707f
	#define INSN_MATCH_LHU 0x5003
	#define INSN_MASK_LHU 0x707f
	#define INSN_MATCH_LWU 0x6003
	#define INSN_MASK_LWU 0x707f
	#define INSN_MATCH_SB 0x23
	#define INSN_MASK_SB 0x707f
	#define INSN_MATCH_SH 0x1023
	#define INSN_MASK_SH 0x707f
	#define INSN_MATCH_SW 0x2023
	#define INSN_MASK_SW 0x707f
	#define INSN_MATCH_SD 0x3023
	#define INSN_MASK_SD 0x707f

	#define INSN_MATCH_FLW 0x2007
	#define INSN_MASK_FLW 0x707f
	#define INSN_MATCH_FLD 0x3007
	#define INSN_MASK_FLD 0x707f
	#define INSN_MATCH_FLQ 0x4007
	#define INSN_MASK_FLQ 0x707f
	#define INSN_MATCH_FSW 0x2027
	#define INSN_MASK_FSW 0x707f
	#define INSN_MATCH_FSD 0x3027
	#define INSN_MASK_FSD 0x707f
	#define INSN_MATCH_FSQ 0x4027
	#define INSN_MASK_FSQ 0x707f

	#define INSN_MATCH_C_LD 0x6000
	#define INSN_MASK_C_LD 0xe003
	#define INSN_MATCH_C_SD 0xe000
	#define INSN_MASK_C_SD 0xe003
	#define INSN_MATCH_C_LW 0x4000
	#define INSN_MASK_C_LW 0xe003
	#define INSN_MATCH_C_SW 0xc000
	#define INSN_MASK_C_SW 0xe003
	#define INSN_MATCH_C_LDSP 0x6002
	#define INSN_MASK_C_LDSP 0xe003
	#define INSN_MATCH_C_SDSP 0xe002
	#define INSN_MASK_C_SDSP 0xe003
	#define INSN_MATCH_C_LWSP 0x4002
	#define INSN_MASK_C_LWSP 0xe003
	#define INSN_MATCH_C_SWSP 0xc002
	#define INSN_MASK_C_SWSP 0xe003

	#define INSN_MATCH_C_FLD 0x2000
	#define INSN_MASK_C_FLD 0xe003
	#define INSN_MATCH_C_FLW 0x6000
	#define INSN_MASK_C_FLW 0xe003
	#define INSN_MATCH_C_FSD 0xa000
	#define INSN_MASK_C_FSD 0xe003
	#define INSN_MATCH_C_FSW 0xe000
	#define INSN_MASK_C_FSW 0xe003
	#define INSN_MATCH_C_FLDSP 0x2002
	#define INSN_MASK_C_FLDSP 0xe003
	#define INSN_MATCH_C_FSDSP 0xa002
	#define INSN_MASK_C_FSDSP 0xe003
	#define INSN_MATCH_C_FLWSP 0x6002
	#define INSN_MASK_C_FLWSP 0xe003
	#define INSN_MATCH_C_FSWSP 0xe002
	#define INSN_MASK_C_FSWSP 0xe003

	#define INSN_LEN(insn) ((((insn) & 0x3) < 0x3) ? 2 : 4)

	#if defined(CONFIG_64BIT)
	#define LOG_REGBYTES 3
	#define XLEN 64
	#else
	#define LOG_REGBYTES 2
	#define XLEN 32
	#endif
	#define REGBYTES (1 << LOG_REGBYTES)
	#define XLEN_MINUS_16 ((XLEN) - 16)

	#define SH_RD 7
	#define SH_RS1 15
	#define SH_RS2 20
	#define SH_RS2C 2

	#define RV_X(x, s, n) (((x) >> (s)) & ((1 << (n)) - 1))
	#define RVC_LW_IMM(x) ((RV_X(x, 6, 1) << 2) \| \
	(RV_X(x, 10, 3) << 3) \| \
	(RV_X(x, 5, 1) << 6))
	#define RVC_LD_IMM(x) ((RV_X(x, 10, 3) << 3) \| \
	(RV_X(x, 5, 2) << 6))
	#define RVC_LWSP_IMM(x) ((RV_X(x, 4, 3) << 2) \| \
	(RV_X(x, 12, 1) << 5) \| \
	(RV_X(x, 2, 2) << 6))
	#define RVC_LDSP_IMM(x) ((RV_X(x, 5, 2) << 3) \| \
	(RV_X(x, 12, 1) << 5) \| \
	(RV_X(x, 2, 3) << 6))
	#define RVC_SWSP_IMM(x) ((RV_X(x, 9, 4) << 2) \| \
	(RV_X(x, 7, 2) << 6))
	#define RVC_SDSP_IMM(x) ((RV_X(x, 10, 3) << 3) \| \
	(RV_X(x, 7, 3) << 6))
	#define RVC_RS1S(insn) (8 + RV_X(insn, SH_RD, 3))
	#define RVC_RS2S(insn) (8 + RV_X(insn, SH_RS2C, 3))
	#define RVC_RS2(insn) RV_X(insn, SH_RS2C, 5)

	#define SHIFT_RIGHT(x, y) \
	((y) < 0 ? ((x) << -(y)) : ((x) >> (y)))

	#define REG_MASK \
	((1 << (5 + LOG_REGBYTES)) - (1 << LOG_REGBYTES))

	#define REG_OFFSET(insn, pos) \
	(SHIFT_RIGHT((insn), (pos) - LOG_REGBYTES) & REG_MASK)

	#define REG_PTR(insn, pos, regs) \
	(ulong *)((ulong)(regs) + REG_OFFSET(insn, pos))

	#define GET_RM(insn) (((insn) >> 12) & 7)

	#define GET_RS1(insn, regs) (*REG_PTR(insn, SH_RS1, regs))
	#define GET_RS2(insn, regs) (*REG_PTR(insn, SH_RS2, regs))
	#define GET_RS1S(insn, regs) (*REG_PTR(RVC_RS1S(insn), 0, regs))
	#define GET_RS2S(insn, regs) (*REG_PTR(RVC_RS2S(insn), 0, regs))
	#define GET_RS2C(insn, regs) (*REG_PTR(insn, SH_RS2C, regs))
	#define GET_SP(regs) (*REG_PTR(2, 0, regs))
	#define SET_RD(insn, regs, val) (*REG_PTR(insn, SH_RD, regs) = (val))
	#define IMM_I(insn) ((s32)(insn) >> 20)
	#define IMM_S(insn) (((s32)(insn) >> 25 << 5) \| \
	(s32)(((insn) >> 7) & 0x1f))
	#define MASK_FUNCT3 0x7000

	#define GET_PRECISION(insn) (((insn) >> 25) & 3)
	#define GET_RM(insn) (((insn) >> 12) & 7)
	#define PRECISION_S 0
	#define PRECISION_D 1

	#define STR(x) XSTR(x)
	#define XSTR(x) #x

	#define DECLARE_UNPRIVILEGED_LOAD_FUNCTION(type, insn) \
	static inline type load_##type(const type *addr) \
	{ \
	type val; \
	asm (#insn " %0, %1" \
	: "=&r" (val) : "m" (*addr)); \
	return val; \
	}

	#define DECLARE_UNPRIVILEGED_STORE_FUNCTION(type, insn) \
	static inline void store_##type(type *addr, type val) \
	{ \
	asm volatile (#insn " %0, %1\n" \
	: : "r" (val), "m" (*addr)); \
	}

	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u8, lbu)
	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u16, lhu)
	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(s8, lb)
	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(s16, lh)
	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(s32, lw)
	DECLARE_UNPRIVILEGED_STORE_FUNCTION(u8, sb)
	DECLARE_UNPRIVILEGED_STORE_FUNCTION(u16, sh)
	DECLARE_UNPRIVILEGED_STORE_FUNCTION(u32, sw)
	#if defined(CONFIG_64BIT)
	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u32, lwu)
	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u64, ld)
	DECLARE_UNPRIVILEGED_STORE_FUNCTION(u64, sd)
	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(ulong, ld)
	#else
	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u32, lw)
	DECLARE_UNPRIVILEGED_LOAD_FUNCTION(ulong, lw)

	static inline u64 load_u64(const u64 *addr)
	{
	return load_u32((u32 *)addr)
	+ ((u64)load_u32((u32 *)addr + 1) << 32);
	}

	static inline void store_u64(u64 *addr, u64 val)
	{
	store_u32((u32 *)addr, val);
	store_u32((u32 *)addr + 1, val >> 32);
	}
	#endif

	static inline ulong get_insn(ulong mepc)
	{
	register ulong __mepc asm ("a2") = mepc;
	ulong val, rvc_mask = 3, tmp;

	asm ("and %[tmp], %[addr], 2\n"
	"bnez %[tmp], 1f\n"
	#if defined(CONFIG_64BIT)
	STR(LWU) " %[insn], (%[addr])\n"
	#else
	STR(LW) " %[insn], (%[addr])\n"
	#endif
	"and %[tmp], %[insn], %[rvc_mask]\n"
	"beq %[tmp], %[rvc_mask], 2f\n"
	"sll %[insn], %[insn], %[xlen_minus_16]\n"
	"srl %[insn], %[insn], %[xlen_minus_16]\n"
	"j 2f\n"
	"1:\n"
	"lhu %[insn], (%[addr])\n"
	"and %[tmp], %[insn], %[rvc_mask]\n"
	"bne %[tmp], %[rvc_mask], 2f\n"
	"lhu %[tmp], 2(%[addr])\n"
	"sll %[tmp], %[tmp], 16\n"
	"add %[insn], %[insn], %[tmp]\n"
	"2:"
	: [insn] "=&r" (val), [tmp] "=&r" (tmp)
	: [addr] "r" (__mepc), [rvc_mask] "r" (rvc_mask),
	[xlen_minus_16] "i" (XLEN_MINUS_16));

	return val;
	}

	union reg_data {
	u8 data_bytes[8];
	ulong data_ulong;
	u64 data_u64;
	};

	int handle_misaligned_load(struct pt_regs *regs)
	{
	union reg_data val;
	unsigned long epc = regs->epc;
	unsigned long insn = get_insn(epc);
	unsigned long addr = csr_read(mtval);
	int i, fp = 0, shift = 0, len = 0;

	regs->epc = 0;

	if ((insn & INSN_MASK_LW) == INSN_MATCH_LW) {
	len = 4;
	shift = 8 * (sizeof(unsigned long) - len);
	#if defined(CONFIG_64BIT)
	} else if ((insn & INSN_MASK_LD) == INSN_MATCH_LD) {
	len = 8;
	shift = 8 * (sizeof(unsigned long) - len);
	} else if ((insn & INSN_MASK_LWU) == INSN_MATCH_LWU) {
	len = 4;
	#endif
	} else if ((insn & INSN_MASK_FLD) == INSN_MATCH_FLD) {
	fp = 1;
	len = 8;
	} else if ((insn & INSN_MASK_FLW) == INSN_MATCH_FLW) {
	fp = 1;
	len = 4;
	} else if ((insn & INSN_MASK_LH) == INSN_MATCH_LH) {
	len = 2;
	shift = 8 * (sizeof(unsigned long) - len);
	} else if ((insn & INSN_MASK_LHU) == INSN_MATCH_LHU) {
	len = 2;
	#if defined(CONFIG_64BIT)
	} else if ((insn & INSN_MASK_C_LD) == INSN_MATCH_C_LD) {
	len = 8;
	shift = 8 * (sizeof(unsigned long) - len);
	insn = RVC_RS2S(insn) << SH_RD;
	} else if ((insn & INSN_MASK_C_LDSP) == INSN_MATCH_C_LDSP &&
	((insn >> SH_RD) & 0x1f)) {
	len = 8;
	shift = 8 * (sizeof(unsigned long) - len);
	#endif
	} else if ((insn & INSN_MASK_C_LW) == INSN_MATCH_C_LW) {
	len = 4;
	shift = 8 * (sizeof(unsigned long) - len);
	insn = RVC_RS2S(insn) << SH_RD;
	} else if ((insn & INSN_MASK_C_LWSP) == INSN_MATCH_C_LWSP &&
	((insn >> SH_RD) & 0x1f)) {
	len = 4;
	shift = 8 * (sizeof(unsigned long) - len);
	} else if ((insn & INSN_MASK_C_FLD) == INSN_MATCH_C_FLD) {
	fp = 1;
	len = 8;
	insn = RVC_RS2S(insn) << SH_RD;
	} else if ((insn & INSN_MASK_C_FLDSP) == INSN_MATCH_C_FLDSP) {
	fp = 1;
	len = 8;
	#if defined(CONFIG_32BIT)
	} else if ((insn & INSN_MASK_C_FLW) == INSN_MATCH_C_FLW) {
	fp = 1;
	len = 4;
	insn = RVC_RS2S(insn) << SH_RD;
	} else if ((insn & INSN_MASK_C_FLWSP) == INSN_MATCH_C_FLWSP) {
	fp = 1;
	len = 4;
	#endif
	} else {
	regs->epc = epc;
	return -1;
	}

	val.data_u64 = 0;
	for (i = 0; i < len; i++)
	val.data_bytes[i] = load_u8((void *)(addr + i));

	if (fp)
	return -1;
	SET_RD(insn, regs, val.data_ulong << shift >> shift);

	regs->epc = epc + INSN_LEN(insn);

	return 0;
	}

	int handle_misaligned_store(struct pt_regs *regs)
	{
	union reg_data val;
	unsigned long epc = regs->epc;
	unsigned long insn = get_insn(epc);
	unsigned long addr = csr_read(mtval);
	int i, len = 0;

	regs->epc = 0;

	val.data_ulong = GET_RS2(insn, regs);

	if ((insn & INSN_MASK_SW) == INSN_MATCH_SW) {
	len = 4;
	#if defined(CONFIG_64BIT)
	} else if ((insn & INSN_MASK_SD) == INSN_MATCH_SD) {
	len = 8;
	#endif
	} else if ((insn & INSN_MASK_SH) == INSN_MATCH_SH) {
	len = 2;
	#if defined(CONFIG_64BIT)
	} else if ((insn & INSN_MASK_C_SD) == INSN_MATCH_C_SD) {
	len = 8;
	val.data_ulong = GET_RS2S(insn, regs);
	} else if ((insn & INSN_MASK_C_SDSP) == INSN_MATCH_C_SDSP &&
	((insn >> SH_RD) & 0x1f)) {
	len = 8;
	val.data_ulong = GET_RS2C(insn, regs);
	#endif
	} else if ((insn & INSN_MASK_C_SW) == INSN_MATCH_C_SW) {
	len = 4;
	val.data_ulong = GET_RS2S(insn, regs);
	} else if ((insn & INSN_MASK_C_SWSP) == INSN_MATCH_C_SWSP &&
	((insn >> SH_RD) & 0x1f)) {
	len = 4;
	val.data_ulong = GET_RS2C(insn, regs);
	} else {
	regs->epc = epc;
	return -1;
	}

	for (i = 0; i < len; i++)
	store_u8((void *)(addr + i), val.data_bytes[i]);

	regs->epc = epc + INSN_LEN(insn);

	return 0;
	}