diff options
Diffstat (limited to 'lib/sbi')
| -rw-r--r-- | lib/sbi/sbi_trap_ldst.c | 46 | ||||
| -rw-r--r-- | lib/sbi/sbi_trap_v_ldst.c | 31 |
2 files changed, 59 insertions, 18 deletions
diff --git a/lib/sbi/sbi_trap_ldst.c b/lib/sbi/sbi_trap_ldst.c index c1392251..5f7de662 100644 --- a/lib/sbi/sbi_trap_ldst.c +++ b/lib/sbi/sbi_trap_ldst.c @@ -32,16 +32,40 @@ typedef int (*sbi_trap_st_emulator)(ulong insn, int wlen, ulong waddr, union sbi_ldst_data in_val, struct sbi_trap_context *tcntx); -ulong sbi_misaligned_tinst_fixup(ulong orig_tinst, ulong new_tinst, - ulong addr_offset) +/** + * Handling of misaligned fault is done by a collection of smaller, but + * aligned load/store(s). Another fault (load/store, page fault...) can + * arise from any of them, then the handling gets aborted. We must fixup + * the tinst to pretend the fault was rised from the original insn. + * Specifically, fixup the offset field using the tval diff between the + * new trap and the original one (if required). + */ +static inline void sbi_misaligned_tinst_fixup( + const struct sbi_trap_info *orig_trap, + struct sbi_trap_info *uptrap) { - if (new_tinst == INSN_PSEUDO_VS_LOAD || - new_tinst == INSN_PSEUDO_VS_STORE) - return new_tinst; - else if (orig_tinst == 0) - return 0UL; + ulong offset = uptrap->tval - orig_trap->tval; + + /* + * The function is called in code path for handling a scalar + * load/store misaligned fault, thus the new uptrap can't have + * custom value of tinst + */ + if (uptrap->tinst == INSN_PSEUDO_VS_LOAD || + uptrap->tinst == INSN_PSEUDO_VS_STORE) + /* Use uptrap as-is for guest-page faults */ + return; + /* + * Only fixup if orig tinst is valid. Otherwise, discard the + * new tinst to be on the safe side. Never use new tinst as-is! + * It's load/store width surely mismatches the original width. + * For vector, discard it regardless. It doesn't make sense to + * have a transformed tinst + */ + else if (orig_trap->tinst == 0) + uptrap->tinst = 0; else - return orig_tinst | (addr_offset << SH_RS1); + uptrap->tinst = orig_trap->tinst | (offset << SH_RS1); } static inline bool sbi_trap_tinst_valid(ulong tinst) @@ -464,8 +488,7 @@ static int sbi_misaligned_ld_emulator(ulong insn, int rlen, ulong addr, out_val->data_bytes[i] = sbi_load_u8((void *)(addr + i), &uptrap); if (uptrap.cause) { - uptrap.tinst = sbi_misaligned_tinst_fixup( - orig_trap->tinst, uptrap.tinst, i); + sbi_misaligned_tinst_fixup(orig_trap, &uptrap); return sbi_trap_redirect(regs, &uptrap); } } @@ -501,8 +524,7 @@ static int sbi_misaligned_st_emulator(ulong insn, int wlen, ulong addr, sbi_store_u8((void *)(addr + i), in_val.data_bytes[i], &uptrap); if (uptrap.cause) { - uptrap.tinst = sbi_misaligned_tinst_fixup( - orig_trap->tinst, uptrap.tinst, i); + sbi_misaligned_tinst_fixup(orig_trap, &uptrap); return sbi_trap_redirect(regs, &uptrap); } } diff --git a/lib/sbi/sbi_trap_v_ldst.c b/lib/sbi/sbi_trap_v_ldst.c index 139d134b..6952bc72 100644 --- a/lib/sbi/sbi_trap_v_ldst.c +++ b/lib/sbi/sbi_trap_v_ldst.c @@ -138,9 +138,31 @@ static inline void vsetvl(ulong vl, ulong vtype) :: "r" (vl), "r" (vtype)); } +/** + * Handling of misaligned fault is done by a collection of smaller, but + * aligned load/store(s). Another fault (load/store, page fault...) can + * arise from any of them, then the handling gets aborted. We must fixup + * the tinst to pretend the fault was rised from the original insn. For + * vector insn, simply null out tinst if it's not a guest-page fault, as + * there's no transformed insn for vector load/store + */ +static inline void sbi_misaligned_v_tinst_fixup(struct sbi_trap_info *uptrap) +{ + /* + * The function is called in code path for handling a vector + * load/store misaligned fault, thus the new uptrap can't have + * custom value of tinst + */ + if (uptrap->tinst == INSN_PSEUDO_VS_LOAD || + uptrap->tinst == INSN_PSEUDO_VS_STORE) + /* Use uptrap as-is for guest-page faults */ + return; + + uptrap->tinst = 0; +} + int sbi_misaligned_v_ld_emulator(ulong insn, struct sbi_trap_context *tcntx) { - const struct sbi_trap_info *orig_trap = &tcntx->trap; struct sbi_trap_regs *regs = &tcntx->regs; struct sbi_trap_info uptrap; ulong vl = csr_read(CSR_VL); @@ -218,8 +240,7 @@ int sbi_misaligned_v_ld_emulator(ulong insn, struct sbi_trap_context *tcntx) break; } vsetvl(vl, vtype); - uptrap.tinst = sbi_misaligned_tinst_fixup( - orig_trap->tinst, uptrap.tinst, i); + sbi_misaligned_v_tinst_fixup(&uptrap); return sbi_trap_redirect(regs, &uptrap); } } @@ -240,7 +261,6 @@ int sbi_misaligned_v_ld_emulator(ulong insn, struct sbi_trap_context *tcntx) int sbi_misaligned_v_st_emulator(ulong insn, struct sbi_trap_context *tcntx) { - const struct sbi_trap_info *orig_trap = &tcntx->trap; struct sbi_trap_regs *regs = &tcntx->regs; struct sbi_trap_info uptrap; ulong vl = csr_read(CSR_VL); @@ -317,8 +337,7 @@ int sbi_misaligned_v_st_emulator(ulong insn, struct sbi_trap_context *tcntx) bytes[seg * len + i], &uptrap); if (uptrap.cause) { vsetvl(vl, vtype); - uptrap.tinst = sbi_misaligned_tinst_fixup( - orig_trap->tinst, uptrap.tinst, i); + sbi_misaligned_v_tinst_fixup(&uptrap); return sbi_trap_redirect(regs, &uptrap); } } |