diff options
author | Jiong Wang <jiong.wang@arm.com> | 2014-10-24 11:39:35 +0100 |
---|---|---|
committer | Jiong Wang <jiong.wang@arm.com> | 2014-10-24 11:39:35 +0100 |
commit | 68fcca92b735bb46e38331485ac2e933e5876b83 (patch) | |
tree | 586a3f1bf8c983437c2f084e078cd6402a930e7c | |
parent | 79ccd89e582a1159a503813be020d044e070d53f (diff) | |
download | gdb-68fcca92b735bb46e38331485ac2e933e5876b83.zip gdb-68fcca92b735bb46e38331485ac2e933e5876b83.tar.gz gdb-68fcca92b735bb46e38331485ac2e933e5876b83.tar.bz2 |
[AArch64] Cortex-A53 erratum 835769 linker workaround
2014-10-22 Tejas Belagod <tejas.belagod@arm.com>
bfd/
* bfd-in.h (bfd_elf64_aarch64_set_options): Add a parameter.
* bfd-in2.h (bfd_elf64_aarch64_set_options): Likewise.
* elfnn-aarch64.c (aarch64_erratum_835769_stub): New.
(elf_aarch64_stub_type): Add new type
aarch64_stub_erratum_835769_veneer.
(elf_aarch64_stub_hash_entry): New fields for erratum 835769.
(aarch64_erratum_835769_fix): New data struct to record erratum
835769.
(elf_aarch64_link_hash_table: Global flags for 835769.
(aarch64_build_one_stub): Add case for 835769.
(aarch64_size_one_stub): Likewise.
(aarch64_mem_op_p, aarch64_mlxl_p,
aarch64_erratum_sequence,erratum_835769_scan):
New. Decode and scan functions for erratum 835769.
(elf_aarch64_create_or_find_stub_sec): New.
(elfNN_aarch64_size_stubs): Look for erratum 835769 and record
them.
(bfd_elfNN_aarch64_set_options: Set global flag for 835769.
(erratum_835769_branch_to_stub_data,
make_branch_to_erratum_835769_stub):New. Connect up all the
erratum stubs to occurances by branches.
(elfNN_aarch64_write_section): New hook.
(aarch64_map_one_stub): Output erratum stub symbol.
(elfNN_aarch64_size_dynamic_sections): Init mapping symbol
information for erratum 835769.
(elf_backend_write_section): Define.
ld/
* emultempl/aarch64elf.em: Add command-line option for erratum
835769.
ld/testsuite/
* ld-aarch64/aarch64-elf.exp (aarch64elftests): Drive erratum
835769 tests.
* ld-aarch64/erratum835769.d: New.
* ld-aarch64/erratum835769.s: New.
-rw-r--r-- | bfd/ChangeLog | 29 | ||||
-rw-r--r-- | bfd/bfd-in.h | 4 | ||||
-rw-r--r-- | bfd/bfd-in2.h | 4 | ||||
-rw-r--r-- | bfd/elfnn-aarch64.c | 641 | ||||
-rw-r--r-- | ld/ChangeLog | 4 | ||||
-rw-r--r-- | ld/emultempl/aarch64elf.em | 10 | ||||
-rw-r--r-- | ld/ld.texinfo | 7 | ||||
-rw-r--r-- | ld/testsuite/ChangeLog | 7 | ||||
-rw-r--r-- | ld/testsuite/ld-aarch64/aarch64-elf.exp | 8 | ||||
-rw-r--r-- | ld/testsuite/ld-aarch64/erratum835769.d | 48 | ||||
-rw-r--r-- | ld/testsuite/ld-aarch64/erratum835769.s | 75 |
11 files changed, 829 insertions, 8 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 79bc784..04b6d86 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,32 @@ +2014-10-24 Tejas Belagod <tejas.belagod@arm.com> + + * bfd-in.h (bfd_elf64_aarch64_set_options): Add a parameter. + * bfd-in2.h (bfd_elf64_aarch64_set_options): Likewise. + * elfnn-aarch64.c (aarch64_erratum_835769_stub): New. + (elf_aarch64_stub_type): Add new type + aarch64_stub_erratum_835769_veneer. + (elf_aarch64_stub_hash_entry): New fields for erratum 835769. + (aarch64_erratum_835769_fix): New data struct to record erratum + 835769. + (elf_aarch64_link_hash_table: Global flags for 835769. + (aarch64_build_one_stub): Add case for 835769. + (aarch64_size_one_stub): Likewise. + (aarch64_mem_op_p, aarch64_mlxl_p, + aarch64_erratum_sequence,erratum_835769_scan): + New. Decode and scan functions for erratum 835769. + (elf_aarch64_create_or_find_stub_sec): New. + (elfNN_aarch64_size_stubs): Look for erratum 835769 and record + them. + (bfd_elfNN_aarch64_set_options: Set global flag for 835769. + (erratum_835769_branch_to_stub_data, + make_branch_to_erratum_835769_stub):New. Connect up all the + erratum stubs to occurances by branches. + (elfNN_aarch64_write_section): New hook. + (aarch64_map_one_stub): Output erratum stub symbol. + (elfNN_aarch64_size_dynamic_sections): Init mapping symbol + information for erratum 835769. + (elf_backend_write_section): Define. + 2014-10-23 Victor Kamensky <victor.kamensky@linaro.org> * elf32-arm.c (read_code32): New function to read 32 bit diff --git a/bfd/bfd-in.h b/bfd/bfd-in.h index bcb9fdc..1f80a76 100644 --- a/bfd/bfd-in.h +++ b/bfd/bfd-in.h @@ -937,10 +937,10 @@ extern void bfd_elf32_aarch64_init_maps (bfd *); extern void bfd_elf64_aarch64_set_options - (bfd *, struct bfd_link_info *, int, int, int); + (bfd *, struct bfd_link_info *, int, int, int, int); extern void bfd_elf32_aarch64_set_options - (bfd *, struct bfd_link_info *, int, int, int); + (bfd *, struct bfd_link_info *, int, int, int, int); /* ELF AArch64 mapping symbol support. */ #define BFD_AARCH64_SPECIAL_SYM_TYPE_MAP (1 << 0) diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h index 928aa35..c7a2bb5 100644 --- a/bfd/bfd-in2.h +++ b/bfd/bfd-in2.h @@ -944,10 +944,10 @@ extern void bfd_elf32_aarch64_init_maps (bfd *); extern void bfd_elf64_aarch64_set_options - (bfd *, struct bfd_link_info *, int, int, int); + (bfd *, struct bfd_link_info *, int, int, int, int); extern void bfd_elf32_aarch64_set_options - (bfd *, struct bfd_link_info *, int, int, int); + (bfd *, struct bfd_link_info *, int, int, int, int); /* ELF AArch64 mapping symbol support. */ #define BFD_AARCH64_SPECIAL_SYM_TYPE_MAP (1 << 0) diff --git a/bfd/elfnn-aarch64.c b/bfd/elfnn-aarch64.c index 9e00069..19ad4d2 100644 --- a/bfd/elfnn-aarch64.c +++ b/bfd/elfnn-aarch64.c @@ -1611,6 +1611,12 @@ static const uint32_t aarch64_long_branch_stub[] = 0x00000000, }; +static const uint32_t aarch64_erratum_835769_stub[] = +{ + 0x00000000, /* Placeholder for multiply accumulate. */ + 0x14000000, /* b <label> */ +}; + /* Section name for stubs is the associated section name plus this string. */ #define STUB_SUFFIX ".stub" @@ -1620,6 +1626,7 @@ enum elf_aarch64_stub_type aarch64_stub_none, aarch64_stub_adrp_branch, aarch64_stub_long_branch, + aarch64_stub_erratum_835769_veneer, }; struct elf_aarch64_stub_hash_entry @@ -1654,6 +1661,10 @@ struct elf_aarch64_stub_hash_entry stub name in the hash table has to be unique; this does not, so it can be friendlier. */ char *output_name; + + /* The instruction which caused this stub to be generated (only valid for + erratum 835769 workaround stubs at present). */ + uint32_t veneered_insn; }; /* Used to build a map of a section. This is required for mixed-endian @@ -1679,6 +1690,17 @@ _aarch64_elf_section_data; #define elf_aarch64_section_data(sec) \ ((_aarch64_elf_section_data *) elf_section_data (sec)) +/* A fix-descriptor for erratum 835769. */ +struct aarch64_erratum_835769_fix +{ + bfd *input_bfd; + asection *section; + bfd_vma offset; + uint32_t veneered_insn; + char *stub_name; + enum elf_aarch64_stub_type stub_type; +}; + /* The size of the thread control block which is defined to be two pointers. */ #define TCB_SIZE (ARCH_SIZE/8)*2 @@ -1799,6 +1821,15 @@ struct elf_aarch64_link_hash_table /* Nonzero to force PIC branch veneers. */ int pic_veneer; + /* Fix erratum 835769. */ + int fix_erratum_835769; + + /* A table of fix locations for erratum 835769. This holds erratum + fix locations between elfNN_aarch64_size_stubs() and + elfNN_aarch64_write_section(). */ + struct aarch64_erratum_835769_fix *aarch64_erratum_835769_fixes; + unsigned int num_aarch64_erratum_835769_fixes; + /* The number of bytes in the initial entry in the PLT. */ bfd_size_type plt_header_size; @@ -2343,6 +2374,9 @@ aarch64_build_one_stub (struct bfd_hash_entry *gen_entry, bfd *stub_bfd; bfd_byte *loc; bfd_vma sym_value; + bfd_vma veneered_insn_loc; + bfd_vma veneer_entry_loc; + bfd_signed_vma branch_offset = 0; unsigned int template_size; const uint32_t *template; unsigned int i; @@ -2383,6 +2417,10 @@ aarch64_build_one_stub (struct bfd_hash_entry *gen_entry, template = aarch64_long_branch_stub; template_size = sizeof (aarch64_long_branch_stub); break; + case aarch64_stub_erratum_835769_veneer: + template = aarch64_erratum_835769_stub; + template_size = sizeof (aarch64_erratum_835769_stub); + break; default: BFD_FAIL (); return FALSE; @@ -2425,6 +2463,23 @@ aarch64_build_one_stub (struct bfd_hash_entry *gen_entry, stub_entry->stub_offset + 16, sym_value + 12, 0); break; + + case aarch64_stub_erratum_835769_veneer: + veneered_insn_loc = stub_entry->target_section->output_section->vma + + stub_entry->target_section->output_offset + + stub_entry->target_value; + veneer_entry_loc = stub_entry->stub_sec->output_section->vma + + stub_entry->stub_sec->output_offset + + stub_entry->stub_offset; + branch_offset = veneered_insn_loc - veneer_entry_loc; + branch_offset >>= 2; + branch_offset &= 0x3ffffff; + bfd_putl32 (stub_entry->veneered_insn, + stub_sec->contents + stub_entry->stub_offset); + bfd_putl32 (template[1] | branch_offset, + stub_sec->contents + stub_entry->stub_offset + 4); + break; + default: break; } @@ -2453,6 +2508,9 @@ aarch64_size_one_stub (struct bfd_hash_entry *gen_entry, case aarch64_stub_long_branch: size = sizeof (aarch64_long_branch_stub); break; + case aarch64_stub_erratum_835769_veneer: + size = sizeof (aarch64_erratum_835769_stub); + break; default: BFD_FAIL (); return FALSE; @@ -2641,6 +2699,388 @@ group_sections (struct elf_aarch64_link_hash_table *htab, #undef PREV_SEC +#define AARCH64_BITS(x, pos, n) (((x) >> (pos)) & ((1 << (n)) - 1)) + +#define AARCH64_RT(insn) AARCH64_BITS (insn, 0, 5) +#define AARCH64_RT2(insn) AARCH64_BITS (insn, 10, 5) +#define AARCH64_RA(insn) AARCH64_BITS (insn, 10, 5) +#define AARCH64_RD(insn) AARCH64_BITS (insn, 0, 5) +#define AARCH64_RN(insn) AARCH64_BITS (insn, 5, 5) +#define AARCH64_RM(insn) AARCH64_BITS (insn, 16, 5) + +#define AARCH64_MAC(insn) (((insn) & 0xff000000) == 0x9b000000) +#define AARCH64_BIT(insn, n) AARCH64_BITS (insn, n, 1) +#define AARCH64_OP31(insn) AARCH64_BITS (insn, 21, 3) +#define AARCH64_ZR 0x1f + +/* All ld/st ops. See C4-182 of the ARM ARM. The encoding space for + LD_PCREL, LDST_RO, LDST_UI and LDST_UIMM cover prefetch ops. */ + +#define AARCH64_LD(insn) (AARCH64_BIT (insn, 22) == 1) +#define AARCH64_LDST(insn) (((insn) & 0x0a000000) == 0x08000000) +#define AARCH64_LDST_EX(insn) (((insn) & 0x3f000000) == 0x08000000) +#define AARCH64_LDST_PCREL(insn) (((insn) & 0x3b000000) == 0x18000000) +#define AARCH64_LDST_NAP(insn) (((insn) & 0x3b800000) == 0x28000000) +#define AARCH64_LDSTP_PI(insn) (((insn) & 0x3b800000) == 0x28800000) +#define AARCH64_LDSTP_O(insn) (((insn) & 0x3b800000) == 0x29000000) +#define AARCH64_LDSTP_PRE(insn) (((insn) & 0x3b800000) == 0x29800000) +#define AARCH64_LDST_UI(insn) (((insn) & 0x3b200c00) == 0x38000000) +#define AARCH64_LDST_PIIMM(insn) (((insn) & 0x3b200c00) == 0x38000400) +#define AARCH64_LDST_U(insn) (((insn) & 0x3b200c00) == 0x38000800) +#define AARCH64_LDST_PREIMM(insn) (((insn) & 0x3b200c00) == 0x38000c00) +#define AARCH64_LDST_RO(insn) (((insn) & 0x3b200c00) == 0x38200800) +#define AARCH64_LDST_UIMM(insn) (((insn) & 0x3b000000) == 0x39000000) +#define AARCH64_LDST_SIMD_M(insn) (((insn) & 0xbfbf0000) == 0x0c000000) +#define AARCH64_LDST_SIMD_M_PI(insn) (((insn) & 0xbfa00000) == 0x0c800000) +#define AARCH64_LDST_SIMD_S(insn) (((insn) & 0xbf9f0000) == 0x0d000000) +#define AARCH64_LDST_SIMD_S_PI(insn) (((insn) & 0xbf800000) == 0x0d800000) + +/* Classify an INSN if it is indeed a load/store. Return TRUE if INSN + is a load/store along with the Rt and Rtn. Return FALSE if not a + load/store. */ + +static bfd_boolean +aarch64_mem_op_p (uint32_t insn, unsigned int *rt, unsigned int *rtn, + bfd_boolean *pair, bfd_boolean *load) +{ + uint32_t opcode; + unsigned int r; + uint32_t opc = 0; + uint32_t v = 0; + uint32_t opc_v = 0; + + /* Bail out quickly if INSN doesn't fall into the the load-store + encoding space. */ + if (!AARCH64_LDST (insn)) + return FALSE; + + *pair = FALSE; + *load = FALSE; + if (AARCH64_LDST_EX (insn)) + { + *rt = AARCH64_RT (insn); + *rtn = *rt; + if (AARCH64_BIT (insn, 21) == 1) + { + *pair = TRUE; + *rtn = AARCH64_RT2 (insn); + } + *load = AARCH64_LD (insn); + return TRUE; + } + else if (AARCH64_LDST_NAP (insn) + || AARCH64_LDSTP_PI (insn) + || AARCH64_LDSTP_O (insn) + || AARCH64_LDSTP_PRE (insn)) + { + *pair = TRUE; + *rt = AARCH64_RT (insn); + *rtn = AARCH64_RT2 (insn); + *load = AARCH64_LD (insn); + return TRUE; + } + else if (AARCH64_LDST_PCREL (insn) + || AARCH64_LDST_UI (insn) + || AARCH64_LDST_PIIMM (insn) + || AARCH64_LDST_U (insn) + || AARCH64_LDST_PREIMM (insn) + || AARCH64_LDST_RO (insn) + || AARCH64_LDST_UIMM (insn)) + { + *rt = AARCH64_RT (insn); + *rtn = *rt; + if (AARCH64_LDST_PCREL (insn)) + *load = TRUE; + opc = AARCH64_BITS (insn, 22, 2); + v = AARCH64_BIT (insn, 26); + opc_v = opc | (v << 2); + *load = (opc_v == 1 || opc_v == 2 || opc_v == 3 + || opc_v == 5 || opc_v == 7); + return TRUE; + } + else if (AARCH64_LDST_SIMD_M (insn) + || AARCH64_LDST_SIMD_M_PI (insn)) + { + *rt = AARCH64_RT (insn); + *load = AARCH64_BIT (insn, 22); + opcode = (insn >> 12) & 0xf; + switch (opcode) + { + case 0: + case 2: + *rtn = *rt + 3; + break; + + case 4: + case 6: + *rtn = *rt + 2; + break; + + case 7: + *rtn = *rt; + break; + + case 8: + case 10: + *rtn = *rt + 1; + break; + + default: + return FALSE; + } + return TRUE; + } + else if (AARCH64_LDST_SIMD_S (insn) + || AARCH64_LDST_SIMD_S_PI (insn)) + { + *rt = AARCH64_RT (insn); + r = (insn >> 21) & 1; + *load = AARCH64_BIT (insn, 22); + opcode = (insn >> 13) & 0x7; + switch (opcode) + { + case 0: + case 2: + case 4: + *rtn = *rt + r; + break; + + case 1: + case 3: + case 5: + *rtn = *rt + (r == 0 ? 2 : 3); + break; + + case 6: + *rtn = *rt + r; + break; + + case 7: + *rtn = *rt + (r == 0 ? 2 : 3); + break; + + default: + return FALSE; + } + return TRUE; + } + + return FALSE; +} + +/* Return TRUE if INSN is multiply-accumulate. */ + +static bfd_boolean +aarch64_mlxl_p (uint32_t insn) +{ + uint32_t op31 = AARCH64_OP31 (insn); + + if (AARCH64_MAC (insn) + && (op31 == 0 || op31 == 1 || op31 == 5) + /* Exclude MUL instructions which are encoded as a multiple accumulate + with RA = XZR. */ + && AARCH64_RA (insn) != AARCH64_ZR) + return TRUE; + + return FALSE; +} + +/* Some early revisions of the Cortex-A53 have an erratum (835769) whereby + it is possible for a 64-bit multiply-accumulate instruction to generate an + incorrect result. The details are quite complex and hard to + determine statically, since branches in the code may exist in some + circumstances, but all cases end with a memory (load, store, or + prefetch) instruction followed immediately by the multiply-accumulate + operation. We employ a linker patching technique, by moving the potentially + affected multiply-accumulate instruction into a patch region and replacing + the original instruction with a branch to the patch. This function checks + if INSN_1 is the memory operation followed by a multiply-accumulate + operation (INSN_2). Return TRUE if an erratum sequence is found, FALSE + if INSN_1 and INSN_2 are safe. */ + +static bfd_boolean +aarch64_erratum_sequence (uint32_t insn_1, uint32_t insn_2) +{ + uint32_t rt; + uint32_t rtn; + uint32_t rn; + uint32_t rm; + uint32_t ra; + bfd_boolean pair; + bfd_boolean load; + + if (aarch64_mlxl_p (insn_2) + && aarch64_mem_op_p (insn_1, &rt, &rtn, &pair, &load)) + { + /* Any SIMD memory op is independent of the subsequent MLA + by definition of the erratum. */ + if (AARCH64_BIT (insn_1, 26)) + return TRUE; + + /* If not SIMD, check for integer memory ops and MLA relationship. */ + rn = AARCH64_RN (insn_2); + ra = AARCH64_RA (insn_2); + rm = AARCH64_RM (insn_2); + + /* If this is a load and there's a true(RAW) dependency, we are safe + and this is not an erratum sequence. */ + if (load && + (rt == rn || rt == rm || rt == ra + || (pair && (rtn == rn || rtn == rm || rtn == ra)))) + return FALSE; + + /* We conservatively put out stubs for all other cases (including + writebacks). */ + return TRUE; + } + + return FALSE; +} + +static bfd_boolean +erratum_835769_scan (bfd *input_bfd, + struct bfd_link_info *info, + struct aarch64_erratum_835769_fix **fixes_p, + unsigned int *num_fixes_p, + unsigned int *fix_table_size_p) +{ + asection *section; + struct elf_aarch64_link_hash_table *htab = elf_aarch64_hash_table (info); + struct aarch64_erratum_835769_fix *fixes = *fixes_p; + unsigned int num_fixes = *num_fixes_p; + unsigned int fix_table_size = *fix_table_size_p; + + if (htab == NULL) + return FALSE; + + for (section = input_bfd->sections; + section != NULL; + section = section->next) + { + bfd_byte *contents = NULL; + struct _aarch64_elf_section_data *sec_data; + unsigned int span; + + if (elf_section_type (section) != SHT_PROGBITS + || (elf_section_flags (section) & SHF_EXECINSTR) == 0 + || (section->flags & SEC_EXCLUDE) != 0 + || (section->sec_info_type == SEC_INFO_TYPE_JUST_SYMS) + || (section->output_section == bfd_abs_section_ptr)) + continue; + + if (elf_section_data (section)->this_hdr.contents != NULL) + contents = elf_section_data (section)->this_hdr.contents; + else if (! bfd_malloc_and_get_section (input_bfd, section, &contents)) + return TRUE; + + sec_data = elf_aarch64_section_data (section); + for (span = 0; span < sec_data->mapcount; span++) + { + unsigned int span_start = sec_data->map[span].vma; + unsigned int span_end = ((span == sec_data->mapcount - 1) + ? sec_data->map[0].vma + section->size + : sec_data->map[span + 1].vma); + unsigned int i; + char span_type = sec_data->map[span].type; + + if (span_type == 'd') + continue; + + for (i = span_start; i + 4 < span_end; i += 4) + { + uint32_t insn_1 = bfd_getl32 (contents + i); + uint32_t insn_2 = bfd_getl32 (contents + i + 4); + + if (aarch64_erratum_sequence (insn_1, insn_2)) + { + char *stub_name = NULL; + stub_name = (char *) bfd_malloc + (strlen ("__erratum_835769_veneer_") + 16); + if (stub_name != NULL) + sprintf + (stub_name,"__erratum_835769_veneer_%d", num_fixes); + else + return TRUE; + + if (num_fixes == fix_table_size) + { + fix_table_size *= 2; + fixes = + (struct aarch64_erratum_835769_fix *) + bfd_realloc (fixes, + sizeof (struct aarch64_erratum_835769_fix) + * fix_table_size); + if (fixes == NULL) + return TRUE; + } + + fixes[num_fixes].input_bfd = input_bfd; + fixes[num_fixes].section = section; + fixes[num_fixes].offset = i + 4; + fixes[num_fixes].veneered_insn = insn_2; + fixes[num_fixes].stub_name = stub_name; + fixes[num_fixes].stub_type = aarch64_stub_erratum_835769_veneer; + num_fixes++; + } + } + } + if (elf_section_data (section)->this_hdr.contents == NULL) + free (contents); + } + + *fixes_p = fixes; + *num_fixes_p = num_fixes; + *fix_table_size_p = fix_table_size; + return FALSE; +} + +/* Find or create a stub section. Returns a pointer to the stub section, and + the section to which the stub section will be attached (in *LINK_SEC_P). + LINK_SEC_P may be NULL. */ + +static asection * +elf_aarch64_create_or_find_stub_sec (asection **link_sec_p, asection *section, + struct elf_aarch64_link_hash_table *htab) +{ + asection *link_sec; + asection *stub_sec; + + link_sec = htab->stub_group[section->id].link_sec; + BFD_ASSERT (link_sec != NULL); + stub_sec = htab->stub_group[section->id].stub_sec; + + if (stub_sec == NULL) + { + stub_sec = htab->stub_group[link_sec->id].stub_sec; + if (stub_sec == NULL) + { + size_t namelen; + bfd_size_type len; + char *s_name; + + namelen = strlen (link_sec->name); + len = namelen + sizeof (STUB_SUFFIX); + s_name = (char *) bfd_alloc (htab->stub_bfd, len); + if (s_name == NULL) + return NULL; + + memcpy (s_name, link_sec->name, namelen); + memcpy (s_name + namelen, STUB_SUFFIX, sizeof (STUB_SUFFIX)); + stub_sec = (*htab->add_stub_section) (s_name, link_sec); + + if (stub_sec == NULL) + return NULL; + htab->stub_group[link_sec->id].stub_sec = stub_sec; + } + htab->stub_group[section->id].stub_sec = stub_sec; + } + + if (link_sec_p) + *link_sec_p = link_sec; + + return stub_sec; +} + /* Determine and set the size of the stub section for a final link. The basic idea here is to examine all the relocations looking for @@ -2660,6 +3100,21 @@ elfNN_aarch64_size_stubs (bfd *output_bfd, bfd_boolean stubs_always_before_branch; bfd_boolean stub_changed = 0; struct elf_aarch64_link_hash_table *htab = elf_aarch64_hash_table (info); + struct aarch64_erratum_835769_fix *erratum_835769_fixes = NULL; + unsigned int num_erratum_835769_fixes = 0; + unsigned int erratum_835769_fix_table_size = 10; + unsigned int i; + + if (htab->fix_erratum_835769) + { + erratum_835769_fixes + = (struct aarch64_erratum_835769_fix *) + bfd_zmalloc + (sizeof (struct aarch64_erratum_835769_fix) * + erratum_835769_fix_table_size); + if (erratum_835769_fixes == NULL) + goto error_ret_free_local; + } /* Propagate mach to stub bfd, because it may not have been finalized when we created stub_bfd. */ @@ -2690,7 +3145,9 @@ elfNN_aarch64_size_stubs (bfd *output_bfd, bfd *input_bfd; unsigned int bfd_indx; asection *stub_sec; + unsigned prev_num_erratum_835769_fixes = num_erratum_835769_fixes; + num_erratum_835769_fixes = 0; for (input_bfd = info->input_bfds, bfd_indx = 0; input_bfd != NULL; input_bfd = input_bfd->link.next, bfd_indx++) { @@ -2943,8 +3400,20 @@ elfNN_aarch64_size_stubs (bfd *output_bfd, if (elf_section_data (section)->relocs == NULL) free (internal_relocs); } + + if (htab->fix_erratum_835769) + { + /* Scan for sequences which might trigger erratum 835769. */ + if (erratum_835769_scan (input_bfd, info, &erratum_835769_fixes, + &num_erratum_835769_fixes, + &erratum_835769_fix_table_size) != 0) + goto error_ret_free_local; + } } + if (prev_num_erratum_835769_fixes != num_erratum_835769_fixes) + stub_changed = TRUE; + if (!stub_changed) break; @@ -2952,15 +3421,76 @@ elfNN_aarch64_size_stubs (bfd *output_bfd, stub sections. */ for (stub_sec = htab->stub_bfd->sections; stub_sec != NULL; stub_sec = stub_sec->next) - stub_sec->size = 0; + { + /* Ignore non-stub sections. */ + if (!strstr (stub_sec->name, STUB_SUFFIX)) + continue; + stub_sec->size = 0; + } bfd_hash_traverse (&htab->stub_hash_table, aarch64_size_one_stub, htab); + /* Add erratum 835769 veneers to stub section sizes too. */ + if (htab->fix_erratum_835769) + for (i = 0; i < num_erratum_835769_fixes; i++) + { + stub_sec = elf_aarch64_create_or_find_stub_sec (NULL, + erratum_835769_fixes[i].section, htab); + + if (stub_sec == NULL) + goto error_ret_free_local; + + stub_sec->size += 8; + } + /* Ask the linker to do its stuff. */ (*htab->layout_sections_again) (); stub_changed = FALSE; } + /* Add stubs for erratum 835769 fixes now. */ + if (htab->fix_erratum_835769) + { + for (i = 0; i < num_erratum_835769_fixes; i++) + { + struct elf_aarch64_stub_hash_entry *stub_entry; + char *stub_name = erratum_835769_fixes[i].stub_name; + asection *section = erratum_835769_fixes[i].section; + unsigned int section_id = erratum_835769_fixes[i].section->id; + asection *link_sec = htab->stub_group[section_id].link_sec; + asection *stub_sec = htab->stub_group[section_id].stub_sec; + + stub_entry = aarch64_stub_hash_lookup (&htab->stub_hash_table, + stub_name, TRUE, FALSE); + if (stub_entry == NULL) + { + (*_bfd_error_handler) (_("%s: cannot create stub entry %s"), + section->owner, + stub_name); + return FALSE; + } + + stub_entry->stub_sec = stub_sec; + stub_entry->stub_offset = 0; + stub_entry->id_sec = link_sec; + stub_entry->stub_type = erratum_835769_fixes[i].stub_type; + stub_entry->target_section = section; + stub_entry->target_value = erratum_835769_fixes[i].offset; + stub_entry->veneered_insn = erratum_835769_fixes[i].veneered_insn; + stub_entry->output_name = erratum_835769_fixes[i].stub_name; + } + + /* Stash the erratum 835769 fix array for use later in + elfNN_aarch64_write_section(). */ + htab->aarch64_erratum_835769_fixes = erratum_835769_fixes; + htab->num_aarch64_erratum_835769_fixes = num_erratum_835769_fixes; + } + else + { + htab->aarch64_erratum_835769_fixes = NULL; + htab->num_aarch64_erratum_835769_fixes = 0; + } + return TRUE; error_ret_free_local: @@ -3053,7 +3583,7 @@ bfd_elfNN_aarch64_init_maps (bfd *abfd) return; if ((abfd->flags & DYNAMIC) != 0) - return; + return; hdr = &elf_symtab_hdr (abfd); localsyms = hdr->sh_info; @@ -3091,12 +3621,14 @@ void bfd_elfNN_aarch64_set_options (struct bfd *output_bfd, struct bfd_link_info *link_info, int no_enum_warn, - int no_wchar_warn, int pic_veneer) + int no_wchar_warn, int pic_veneer, + int fix_erratum_835769) { struct elf_aarch64_link_hash_table *globals; globals = elf_aarch64_hash_table (link_info); globals->pic_veneer = pic_veneer; + globals->fix_erratum_835769 = fix_erratum_835769; BFD_ASSERT (is_aarch64_elf (output_bfd)); elf_aarch64_tdata (output_bfd)->no_enum_size_warning = no_enum_warn; @@ -3406,6 +3938,89 @@ symbol_tlsdesc_got_offset (bfd *input_bfd, struct elf_link_hash_entry *h, return value; } +/* Data for make_branch_to_erratum_835769_stub(). */ + +struct erratum_835769_branch_to_stub_data +{ + asection *output_section; + bfd_byte *contents; +}; + +/* Helper to insert branches to erratum 835769 stubs in the right + places for a particular section. */ + +static bfd_boolean +make_branch_to_erratum_835769_stub (struct bfd_hash_entry *gen_entry, + void *in_arg) +{ + struct elf_aarch64_stub_hash_entry *stub_entry; + struct erratum_835769_branch_to_stub_data *data; + bfd_byte *contents; + unsigned long branch_insn = 0; + bfd_vma veneered_insn_loc, veneer_entry_loc; + bfd_signed_vma branch_offset; + unsigned int target; + bfd *abfd; + + stub_entry = (struct elf_aarch64_stub_hash_entry *) gen_entry; + data = (struct erratum_835769_branch_to_stub_data *) in_arg; + + if (stub_entry->target_section != data->output_section + || stub_entry->stub_type != aarch64_stub_erratum_835769_veneer) + return TRUE; + + contents = data->contents; + veneered_insn_loc = stub_entry->target_section->output_section->vma + + stub_entry->target_section->output_offset + + stub_entry->target_value; + veneer_entry_loc = stub_entry->stub_sec->output_section->vma + + stub_entry->stub_sec->output_offset + + stub_entry->stub_offset; + branch_offset = veneer_entry_loc - veneered_insn_loc; + + abfd = stub_entry->target_section->owner; + if (!aarch64_valid_branch_p (veneer_entry_loc, veneered_insn_loc)) + (*_bfd_error_handler) + (_("%B: error: Erratum 835769 stub out " + "of range (input file too large)"), abfd); + + target = stub_entry->target_value; + branch_insn = 0x14000000; + branch_offset >>= 2; + branch_offset &= 0x3ffffff; + branch_insn |= branch_offset; + bfd_putl32 (branch_insn, &contents[target]); + + return TRUE; +} + +static bfd_boolean +elfNN_aarch64_write_section (bfd *output_bfd ATTRIBUTE_UNUSED, + struct bfd_link_info *link_info, + asection *sec, + bfd_byte *contents) + +{ + struct elf_aarch64_link_hash_table *globals = + elf_aarch64_hash_table (link_info); + + if (globals == NULL) + return FALSE; + + /* Fix code to point to erratum 835769 stubs. */ + if (globals->fix_erratum_835769) + { + struct erratum_835769_branch_to_stub_data data; + + data.output_section = sec; + data.contents = contents; + bfd_hash_traverse (&globals->stub_hash_table, + make_branch_to_erratum_835769_stub, &data); + } + + return FALSE; +} + /* Perform a relocation as part of a final link. */ static bfd_reloc_status_type elfNN_aarch64_final_link_relocate (reloc_howto_type *howto, @@ -5748,6 +6363,13 @@ aarch64_map_one_stub (struct bfd_hash_entry *gen_entry, void *in_arg) if (!elfNN_aarch64_output_map_sym (osi, AARCH64_MAP_DATA, addr + 16)) return FALSE; break; + case aarch64_stub_erratum_835769_veneer: + if (!elfNN_aarch64_output_stub_sym (osi, stub_name, addr, + sizeof (aarch64_erratum_835769_stub))) + return FALSE; + if (!elfNN_aarch64_output_map_sym (osi, AARCH64_MAP_INSN, addr)) + return FALSE; + break; default: BFD_FAIL (); } @@ -6443,6 +7065,16 @@ elfNN_aarch64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED, } } + /* Init mapping symbols information to use later to distingush between + code and data while scanning for erratam 835769. */ + if (htab->fix_erratum_835769) + for (ibfd = info->input_bfds; ibfd != NULL; ibfd = ibfd->link.next) + { + if (!is_aarch64_elf (ibfd)) + continue; + bfd_elfNN_aarch64_init_maps (ibfd); + } + /* We now have determined the sizes of the various dynamic sections. Allocate memory for them. */ relocs = FALSE; @@ -7286,6 +7918,9 @@ const struct elf_size_info elfNN_aarch64_size_info = #define elf_backend_size_info \ elfNN_aarch64_size_info +#define elf_backend_write_section \ + elfNN_aarch64_write_section + #define elf_backend_can_refcount 1 #define elf_backend_can_gc_sections 1 #define elf_backend_plt_readonly 1 diff --git a/ld/ChangeLog b/ld/ChangeLog index 722b837..6d495f7 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,7 @@ +2014-10-24 Tejas Belagod <tejas.belagod@arm.com> + + * emultempl/aarch64elf.em: Add command-line option for erratum 835769. + 2014-10-17 Hans-Peter Nilsson <hp@axis.com> Implement --print-sysroot in ld. diff --git a/ld/emultempl/aarch64elf.em b/ld/emultempl/aarch64elf.em index bb58901..42e8056 100644 --- a/ld/emultempl/aarch64elf.em +++ b/ld/emultempl/aarch64elf.em @@ -30,6 +30,7 @@ fragment <<EOF static int no_enum_size_warning = 0; static int no_wchar_size_warning = 0; static int pic_veneer = 0; +static int fix_erratum_835769 = 0; static void gld${EMULATION_NAME}_before_parse (void) @@ -302,7 +303,7 @@ aarch64_elf_create_output_section_statements (void) bfd_elf${ELFSIZE}_aarch64_set_options (link_info.output_bfd, &link_info, no_enum_size_warning, no_wchar_size_warning, - pic_veneer); + pic_veneer, fix_erratum_835769); stub_file = lang_add_input_file ("linker stubs", lang_input_file_is_fake_enum, @@ -351,6 +352,7 @@ PARSE_AND_LIST_PROLOGUE=' #define OPTION_PIC_VENEER 310 #define OPTION_STUBGROUP_SIZE 311 #define OPTION_NO_WCHAR_SIZE_WARNING 312 +#define OPTION_FIX_ERRATUM_835769 313 ' PARSE_AND_LIST_SHORTOPTS=p @@ -361,6 +363,7 @@ PARSE_AND_LIST_LONGOPTS=' { "pic-veneer", no_argument, NULL, OPTION_PIC_VENEER}, { "stub-group-size", required_argument, NULL, OPTION_STUBGROUP_SIZE }, { "no-wchar-size-warning", no_argument, NULL, OPTION_NO_WCHAR_SIZE_WARNING}, + { "fix-cortex-a53-835769", no_argument, NULL, OPTION_FIX_ERRATUM_835769}, ' PARSE_AND_LIST_OPTIONS=' @@ -378,6 +381,7 @@ PARSE_AND_LIST_OPTIONS=' after each stub section. Values of +/-1 indicate\n\ the linker should choose suitable defaults.\n" )); + fprintf (file, _(" --fix-cortex-a53-835769 Fix erratum 835769\n")); ' PARSE_AND_LIST_ARGS_CASES=' @@ -397,6 +401,10 @@ PARSE_AND_LIST_ARGS_CASES=' pic_veneer = 1; break; + case OPTION_FIX_ERRATUM_835769: + fix_erratum_835769 = 1; + break; + case OPTION_STUBGROUP_SIZE: { const char *end; diff --git a/ld/ld.texinfo b/ld/ld.texinfo index 8eb7ba3..3001bf1 100644 --- a/ld/ld.texinfo +++ b/ld/ld.texinfo @@ -6570,6 +6570,13 @@ The @samp{--fix-cortex-a8} switch enables a link-time workaround for an erratum The erratum only affects Thumb-2 code. Please contact ARM for further details. +@cindex Cortex-A53 erratum 835769 workaround +@kindex --fix-cortex-a53-835769 +@kindex --no-fix-cortex-a53-835769 +The @samp{--fix-cortex-a53-835769} switch enables a link-time workaround for erratum 835769 present on certain early revisions of Cortex-A53 processors. The workaround is disabled by default. It can be enabled by specifying @samp{--fix-cortex-a53-835769}, or disabled unconditionally by specifying @samp{--no-fix-cortex-a53-835769}. + +Please contact ARM for further details. + @kindex --merge-exidx-entries @kindex --no-merge-exidx-entries @cindex Merging exidx entries diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog index d91e15e..d0ab7f5 100644 --- a/ld/testsuite/ChangeLog +++ b/ld/testsuite/ChangeLog @@ -1,3 +1,10 @@ +2014-10-24 Tejas Belagod <tejas.belagod@arm.com> + + * ld-aarch64/aarch64-elf.exp (aarch64elftests): Drive erratum + 835769 tests. + * ld-aarch64/erratum835769.d: New. + * ld-aarch64/erratum835769.s: New. + 2014-10-17 Hans-Peter Nilsson <hp@axis.com> * ld-scripts/sysroot-prefix.exp: Log $ld_sysroot. Handle sysroot diff --git a/ld/testsuite/ld-aarch64/aarch64-elf.exp b/ld/testsuite/ld-aarch64/aarch64-elf.exp index b3f6eb5..a75e070 100644 --- a/ld/testsuite/ld-aarch64/aarch64-elf.exp +++ b/ld/testsuite/ld-aarch64/aarch64-elf.exp @@ -35,6 +35,14 @@ if { ![is_elf_format] || ![istarget "aarch64*-*-*"] } { set aarch64elftests { {"EH Frame merge" "-Ttext 0x8000" "" "" {eh-frame-bar.s eh-frame-foo.s} {{objdump --dwarf=frames eh-frame.d}} "eh-frame"} + {"Erratum 835769 dump test" + "--fix-cortex-a53-835769" "" "" {erratum835769.s} + {{objdump -dr erratum835769.d}} + "erratum835769"} + {"Erratum 835769 dump test -shared" + "--fix-cortex-a53-835769 -shared" "" "" {erratum835769.s} + {{objdump -dr erratum835769.d}} + "erratum835769"} } run_ld_link_tests $aarch64elftests diff --git a/ld/testsuite/ld-aarch64/erratum835769.d b/ld/testsuite/ld-aarch64/erratum835769.d new file mode 100644 index 0000000..a040236 --- /dev/null +++ b/ld/testsuite/ld-aarch64/erratum835769.d @@ -0,0 +1,48 @@ +#... +Disassembly of section .text: +#... +[0-9a-f]+ <a1ldr>: +[ \t0-9a-f]+:[ \t]+b8408c87[ \t]+ldr[ \t]+w7, \[x4,#8\]\! +[ \t0-9a-f]+:[ \t]+1b017c06[ \t]+mul[ \t]+w6, w0, w1 +[ \t0-9a-f]+:[ \t]+f9400084[ \t]+ldr[ \t]+x4, \[x4\] +[ \t0-9a-f]+:[ \t0-9a-z]+[ \t]+b[ \t]+[0-9a-f]+ <__erratum_835769_veneer_0> +[ \t0-9a-f]+:[ \t]+aa0503e0[ \t]+mov[ \t]+x0, x5 +[ \t0-9a-f]+:[ \t]+d65f03c0[ \t]+ret + +[0-9a-f]+ <a5ldr>: +[ \t0-9a-f]+:[ \t]+b8408c87[ \t]+ldr[ \t]+w7, \[x4,#8\]! +[ \t0-9a-f]+:[ \t]+1b017c06[ \t]+mul[ \t]+w6, w0, w1 +[ \t0-9a-f]+:[ \t]+f9400084[ \t]+ldr[ \t]+x4, \[x4\] +[ \t0-9a-f]+:[ \t0-9a-z]+[ \t]+b[ \t]+[0-9a-f]+ <__erratum_835769_veneer_1> +[ \t0-9a-f]+:[ \t]+aa0503e0[ \t]+mov[ \t]+x0, x5 +[ \t0-9a-f]+:[ \t]+d65f03c0[ \t]+ret + +[0-9a-f]+ <a6ldr>: +[ \t0-9a-f]+:[ \t]+b8408c87[ \t]+ldr[ \t]+w7, \[x4,#8\]! +[ \t0-9a-f]+:[ \t]+1b017c06[ \t]+mul[ \t]+w6, w0, w1 +[ \t0-9a-f]+:[ \t]+f9400084[ \t]+ldr[ \t]+x4, \[x4\] +[ \t0-9a-f]+:[ \t]+9b031885[ \t]+madd[ \t]+x5, x4, x3, x6 +[ \t0-9a-f]+:[ \t]+aa0503e0[ \t]+mov[ \t]+x0, x5 +[ \t0-9a-f]+:[ \t]+d65f03c0[ \t]+ret + +[0-9a-f]+ <a7str>: +[ \t0-9a-f]+:[ \t]+b8408c87[ \t]+ldr[ \t]+w7, \[x4,#8\]! +[ \t0-9a-f]+:[ \t]+1b017c06[ \t]+mul[ \t]+w6, w0, w1 +[ \t0-9a-f]+:[ \t]+f9000084[ \t]+str[ \t]+x4, \[x4\] +[ \t0-9a-f]+:[ \t0-9a-z]+[ \t]+b[ \t]+[0-9a-f]+ <__erratum_835769_veneer_2> +[ \t0-9a-f]+:[ \t]+aa0503e0[ \t]+mov[ \t]+x0, x5 +[ \t0-9a-f]+:[ \t]+d65f03c0[ \t]+ret +[ \t0-9a-f]+:[ \t]+00000000[ \t]+.inst[ \t]+0x00000000 ; undefined + +[0-9a-f]+ <__erratum_835769_veneer_2>: +[ \t0-9a-f]+:[ \t]+9b031885[ \t]+madd[ \t]+x5, x4, x3, x6 +[ \t0-9a-f]+:[ \t0-9a-z]+[ \t]+b[ \t]+[0-9a-f]+ <a7str\+0x[0-9a-f]+> + +[0-9a-f]+ <__erratum_835769_veneer_1>: +[ \t0-9a-f]+:[ \t]+9ba31845[ \t]+umaddl[ \t]+x5, w2, w3, x6 +[ \t0-9a-f]+:[ \t0-9a-z]+[ \t]+b[ \t]+[0-9a-f]+ <a5ldr\+0x[0-9a-f]+> + +[0-9a-f]+ <__erratum_835769_veneer_0>: +[ \t0-9a-f]+:[ \t]+9b031845[ \t]+madd[ \t]+x5, x2, x3, x6 +[ \t0-9a-f]+:[ \t0-9a-z]+[ \t]+b[ \t]+[0-9a-f]+ <a1ldr\+0x[0-9a-f]+> +#pass diff --git a/ld/testsuite/ld-aarch64/erratum835769.s b/ld/testsuite/ld-aarch64/erratum835769.s new file mode 100644 index 0000000..d57b5ab --- /dev/null +++ b/ld/testsuite/ld-aarch64/erratum835769.s @@ -0,0 +1,75 @@ + .text + .align 2 + .global main + .type main, %function +main: + stp x29, x30, [sp, -32]! + add x29, sp, 0 + mov x0, -26 + str x0, [x29,16] + mov x0, 26 + str x0, [x29,24] + add x4, x29, 16 + mov x0, -1 + mov x1, 2 + mov x2, -3 + mov x3, 4 + bl a1ldr + add x4, x29, 16 + mov x0, -1 + mov x1, 2 + mov x2, -3 + mov x3, 4 + bl a5ldr + mov w0, 0 + ldp x29, x30, [sp], 32 + ret + .size main, .-main + + .align 2 + .global a1ldr + .type a1ldr, %function +a1ldr: + ldr w7, [x4,8]! + mul w6, w0, w1 + ldr x4, [x4] + madd x5, x2, x3, x6 + mov x0, x5 + ret + .size a1ldr, .-a1ldr + + .align 2 + .global a5ldr + .type a5ldr, %function +a5ldr: + ldr w7, [x4,8]! + mul w6, w0, w1 + ldr x4, [x4] + umaddl x5, w2, w3, x6 + mov x0, x5 + ret + .size a5ldr, .-a5ldr + + .align 2 + .global a6ldr + .type a6ldr, %function +a6ldr: + ldr w7, [x4,8]! + mul w6, w0, w1 + ldr x4, [x4] + madd x5, x4, x3, x6 + mov x0, x5 + ret + .size a6ldr, .-a6ldr + + .align 2 + .global a6ldr + .type a6ldr, %function +a7str: + ldr w7, [x4,8]! + mul w6, w0, w1 + str x4, [x4] + madd x5, x4, x3, x6 + mov x0, x5 + ret + .size a7str, .-a7str |