| // 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 <linux/stringify.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 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) | |
| __stringify(LWU) " %[insn], (%[addr])\n" | |
| #else | |
| __stringify(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; | |
| } |