diff options
Diffstat (limited to 'target/linux/ubicom32/files/arch/ubicom32/kernel/module.c')
| -rw-r--r-- | target/linux/ubicom32/files/arch/ubicom32/kernel/module.c | 463 |
1 files changed, 463 insertions, 0 deletions
diff --git a/target/linux/ubicom32/files/arch/ubicom32/kernel/module.c b/target/linux/ubicom32/files/arch/ubicom32/kernel/module.c new file mode 100644 index 000000000..3d29dc2b8 --- /dev/null +++ b/target/linux/ubicom32/files/arch/ubicom32/kernel/module.c @@ -0,0 +1,463 @@ +/* + * arch/ubicom32/kernel/module.c + * Ubicom32 architecture loadable module support. + * + * (C) Copyright 2009, Ubicom, Inc. + * + * This file is part of the Ubicom32 Linux Kernel Port. + * + * The Ubicom32 Linux Kernel Port is free software: you can redistribute + * it and/or modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, either version 2 of the + * License, or (at your option) any later version. + * + * The Ubicom32 Linux Kernel Port is distributed in the hope that it + * will be useful, but WITHOUT ANY WARRANTY; without even the implied + * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with the Ubicom32 Linux Kernel Port. If not, + * see <http://www.gnu.org/licenses/>. + * + * Ubicom32 implementation derived from (with many thanks): + * arch/m68knommu + * arch/blackfin + * arch/parisc + */ +#include <linux/moduleloader.h> +#include <linux/bug.h> +#include <linux/elf.h> +#include <linux/vmalloc.h> +#include <linux/fs.h> +#include <linux/string.h> +#include <linux/kernel.h> +#include <asm/ocm-alloc.h> + +#if 0 +#define DEBUGP printk +#else +#define DEBUGP(fmt...) +#endif + +static void _module_free_ocm(struct module *mod) +{ + printk(KERN_INFO "module arch cleanup %s: OCM instruction memory free " + " of %d @%p\n", mod->name, mod->arch.ocm_inst_size, + mod->arch.ocm_inst); + + if (mod->arch.ocm_inst) { + ocm_inst_free(mod->arch.ocm_inst); + mod->arch.ocm_inst = 0; + mod->arch.ocm_inst_size = 0; + } +} + +void *module_alloc(unsigned long size) +{ + if (size == 0) + return NULL; + return vmalloc(size); +} + + +/* Free memory returned from module_alloc */ +void module_free(struct module *mod, void *module_region) +{ + vfree(module_region); + /* FIXME: If module_region == mod->init_region, trim exception + table entries. */ + + /* + * This is expected to be final module free, use this to prune the + * ocm + */ + if (module_region && module_region == mod->module_core) + _module_free_ocm(mod); + +} + +/* + * module_frob_arch_sections() + * Called from kernel/module.c allowing arch specific handling of + * sections/headers. + */ +int module_frob_arch_sections(Elf_Ehdr *hdr, + Elf_Shdr *sechdrs, + char *secstrings, + struct module *mod) +{ + Elf_Shdr *s, *sechdrs_end; + void *ocm_inst = NULL; + int ocm_inst_size = 0; + + /* + * Ubicom32 v3 and v4 are almost binary compatible but not completely. + * To be safe check that the module was compiled with the correct -march + * which is flags. + */ +#ifdef CONFIG_UBICOM32_V4 + if ((hdr->e_flags & 0xFFFF) != EF_UBICOM32_V4) { + printk(KERN_WARNING "Module %s was not compiled for " + "ubicom32v4, elf_flags:%x,\n", + mod->name, hdr->e_flags); + return -ENOEXEC; + } +#elif defined CONFIG_UBICOM32_V3 + if ((hdr->e_flags & 0xFFFF) != EF_UBICOM32_V3) { + printk(KERN_WARNING "Module %s was not compiled for " + "ubicom32v3, elf_flags:%x\n", + mod->name, hdr->e_flags); + return -ENOEXEC; + } +#else +#error Unknown/Unsupported ubicom32 architecture. +#endif + + /* + * XXX: sechdrs are vmalloced in kernel/module.c + * and would be vfreed just after module is loaded, + * so we hack to keep the only information we needed + * in mod->arch to correctly free L1 I/D sram later. + * NOTE: this breaks the semantic of mod->arch structure. + */ + sechdrs_end = sechdrs + hdr->e_shnum; + for (s = sechdrs; s < sechdrs_end; ++s) { + if (strncmp(".ocm_text", secstrings + s->sh_name, 9) == 0) + ocm_inst_size += s->sh_size; + } + + if (!ocm_inst_size) + return 0; + + ocm_inst = ocm_inst_alloc(ocm_inst_size, 0 /* internal */); + if (ocm_inst == NULL) { +#ifdef CONFIG_OCM_MODULES_FALLBACK_TO_DDR + printk(KERN_WARNING + "module %s: OCM instruction memory allocation of %d" + "failed, fallback to DDR\n", mod->name, ocm_inst_size); + return 0; +#else + printk(KERN_ERR + "module %s: OCM instruction memory allocation of %d" + "failed.\n", mod->name, ocm_inst_size); + return -ENOMEM; +#endif + } + + mod->arch.ocm_inst = ocm_inst; + mod->arch.ocm_inst_size = ocm_inst_size; + + printk(KERN_INFO + "module %s: OCM instruction memory allocation of %d @%p\n", + mod->name, mod->arch.ocm_inst_size, mod->arch.ocm_inst); + + for (s = sechdrs; s < sechdrs_end; ++s) { + if (strncmp(".ocm_text", secstrings + s->sh_name, 9) == 0) { + memcpy(ocm_inst, (void *)s->sh_addr, s->sh_size); + s->sh_flags &= ~SHF_ALLOC; + s->sh_addr = (unsigned long)ocm_inst; + ocm_inst += s->sh_size; + } + } + + return 0; +} + +int apply_relocate(Elf32_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, + unsigned int relsec, + struct module *me) +{ + DEBUGP("Invalid Applying relocate section %u to %u\n", relsec, + sechdrs[relsec].sh_info); + return -EINVAL; +} + +int apply_relocate_add(Elf32_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, + unsigned int relsec, + struct module *me) +{ + unsigned int i; + Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr; + Elf32_Sym *sym; + uint32_t *location; + uint32_t insn; + + DEBUGP("Applying relocate_add section %u to %u\n", relsec, + sechdrs[relsec].sh_info); + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + uint32_t v; + const int elf32_rtype = ELF32_R_TYPE(rel[i].r_info); + + /* This is where to make the change */ + location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr + + rel[i].r_offset; + /* This is the symbol it is referring to. Note that all + undefined symbols have been resolved. */ + sym = (Elf32_Sym *)sechdrs[symindex].sh_addr + + ELF32_R_SYM(rel[i].r_info); + + v = rel[i].r_addend + sym->st_value; + + + switch (elf32_rtype) { + case R_UBICOM32_32: + { + /* + * Store the 32 bit relocation as is. + */ + *location = v; + break; + } + case R_UBICOM32_HI24: + { + /* + * 24 bit relocation that is part of the MOVEAI + * instruction. The 24 bits come from bits 7 - 30 of the + * relocation. Theses bits eventually get split into 2 + * fields in the instruction encoding. + * + * - Bits 7 - 27 of the relocation are encoded into bits + * 0 - 20 of the instruction. + * + * - Bits 28 - 30 of the relocation are encoded into + * bit 24 - 26 of the instruction. + */ + uint32_t valid24 = (v >> 7) & 0xffffff; + insn = *location; + + insn &= ~(0x1fffff | (0x7 << 24)); + insn |= (valid24 & 0x1fffff); + insn |= ((valid24 & 0xe00000) << 3); + *location = insn; + } + break; + case R_UBICOM32_LO7_S: + case R_UBICOM32_LO7_2_S: + case R_UBICOM32_LO7_4_S: + { + /* + * Bits 0 - 6 of the relocation are encoded into the + * 7bit unsigned immediate fields of the SOURCE-1 field + * of the instruction. The immediate value is left + * shifted by (0, 1, 2) based on the operand size. + */ + uint32_t valid7 = v & 0x7f; + insn = *location; + + if (elf32_rtype == R_UBICOM32_LO7_2_S) { + valid7 >>= 1; + } else if (elf32_rtype == R_UBICOM32_LO7_4_S) { + valid7 >>= 2; + } + + insn &= ~(0x1f | (0x3 << 8)); + insn |= (valid7 & 0x1f); + insn |= ((valid7 & 0x60) << 3); + *location = insn; + } + break; + case R_UBICOM32_LO7_D: + case R_UBICOM32_LO7_2_D: + case R_UBICOM32_LO7_4_D: + { + /* + * Bits 0 - 6 of the relocation are encoded into the + * 7bit unsigned immediate fields of the DESTINATION + * field of the instruction. The immediate value is + * left shifted by (0, 1, 2) based on the operand size. + */ + uint32_t valid7 = v & 0x7f; + insn = *location; + + if (elf32_rtype == R_UBICOM32_LO7_2_D) { + valid7 >>= 1; + } else if (elf32_rtype == R_UBICOM32_LO7_4_D) { + valid7 >>= 2; + } + + insn &= ~((0x1f | (0x3 << 8)) << 16); + insn |= ((valid7 & 0x1f) << 16); + insn |= ((valid7 & 0x60) << 19); + *location = insn; + } + break; + case R_UBICOM32_LO7_CALLI: + case R_UBICOM32_LO16_CALLI: + { + /* + * Extract the offset for a CALLI instruction. The + * offsets can be either 7 bits or 18 bits. Since all + * instructions in ubicom32 architecture are at work + * aligned addresses the truncated offset is right + * shifted by 2 before being encoded in the instruction. + */ + uint32_t val; + if (elf32_rtype == R_UBICOM32_LO7_CALLI) { + val = v & 0x7f; + } else { + val = v & 0x3ffff; + } + + val >>= 2; + + insn = *location; + + insn &= ~0x071f071f; + insn |= (val & 0x1f) << 0; + val >>= 5; + insn |= (val & 0x07) << 8; + val >>= 3; + insn |= (val & 0x1f) << 16; + val >>= 5; + insn |= (val & 0x07) << 24; + *location = insn; + } + break; + case R_UBICOM32_24_PCREL: + { + /* + * Extract 26 bit signed PC relative offset for CALL + * instructions. Since instruction addresses are word + * aligned the offset is right shited by 2 before + * encoding into instruction. + */ + int32_t val = v - (int32_t)location; + + /* + * Check that the top 7 bits are all equal to the sign + * bit (26), i.e all 0's or all 1's. If they are not then + * the absolute difference is greater than 25 bits. + */ + if (((uint32_t)val & 0xFE000000) != 0xFE000000 && + ((uint32_t)val & 0xFE000000) != 0x0) { + /* + * The relocation is beyond our addressable + * range with a 26 bit call. + */ + printk(KERN_ERR "module %s: PC Relative " + "relocation out of range: " + "%u (%x->%x, %x)\n", + me->name, elf32_rtype, + v, (uint32_t) location, val); + return -ENOEXEC; + } + + val = (val & 0x3ffffff) >> 2; + insn = *location; + insn = insn & 0xf8e00000; + + insn |= (val >> 21) << 24; + insn |= (val & 0x1fffff); + *location = insn; + } + break; + case R_UBICOM32_LO16: + case R_UBICOM32_HI16: + { + /* + * 16 bit immediate value that is encoded into bit 0 - + * 15 of the instruction. + */ + uint32_t val; + + if (elf32_rtype == R_UBICOM32_LO16) { + val = v & 0xffff; + } else { + val = (v >> 16) & 0xffff; + } + + insn = *location; + insn &= 0xffff0000; + + insn |= val; + *location = insn; + } + break; + case R_UBICOM32_21_PCREL: + { + /* + * Extract 23 bit signed PC relative offset for JMP<cc> + * instructions. Since instruction addresses are word + * aligned the offset is right shited by 2 before + * encoding into instruction. + */ + int32_t val = v - (int32_t)location; + + val = (val & 0x7fffff) >> 2; + insn = *location; + insn = insn & 0xffe00000; + + insn |= (val >> 21) << 24; + insn |= val; + *location = insn; + } + break; + default: + BUG(); + printk(KERN_ERR "module %s: Unknown relocation: %u\n", + me->name, elf32_rtype); + return -ENOEXEC; + } + } + return 0; +} + +int module_finalize(const Elf_Ehdr *hdr, + const Elf_Shdr *sechdrs, + struct module *mod) +{ + unsigned int i, strindex = 0, symindex = 0; + char *secstrings; + int err; + + err = module_bug_finalize(hdr, sechdrs, mod); + if (err) + return err; + + if (!mod->arch.ocm_inst) { + /* + * No OCM code, so nothing more to do. + */ + return 0; + } + + secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; + + for (i = 1; i < hdr->e_shnum; i++) { + /* Internal symbols and strings. */ + if (sechdrs[i].sh_type == SHT_SYMTAB) { + symindex = i; + strindex = sechdrs[i].sh_link; + } + } + + for (i = 1; i < hdr->e_shnum; i++) { + const char *strtab = (char *)sechdrs[strindex].sh_addr; + unsigned int info = sechdrs[i].sh_info; + + /* Not a valid relocation section? */ + if (info >= hdr->e_shnum) + continue; + + if ((sechdrs[i].sh_type == SHT_RELA) && + (strncmp(".rela.ocm_text", + secstrings + sechdrs[i].sh_name, 5 + 9) == 0)) { + err = apply_relocate_add((Elf_Shdr *) sechdrs, strtab, + symindex, i, mod); + if (err) + return err; + } + } + + return 0; +} + +void module_arch_cleanup(struct module *mod) +{ + module_bug_cleanup(mod); +} |