diff options
Diffstat (limited to 'arch/c6x/kernel/module.c')
-rw-r--r-- | arch/c6x/kernel/module.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/c6x/kernel/module.c b/arch/c6x/kernel/module.c new file mode 100644 index 0000000..5fc03f1 --- /dev/null +++ b/arch/c6x/kernel/module.c @@ -0,0 +1,123 @@ +/* + * Port on Texas Instruments TMS320C6x architecture + * + * Copyright (C) 2005, 2009, 2010, 2011 Texas Instruments Incorporated + * Author: Thomas Charleux (thomas.charleux@jaluna.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ +#include <linux/moduleloader.h> +#include <linux/elf.h> +#include <linux/vmalloc.h> +#include <linux/kernel.h> + +static inline int fixup_pcr(u32 *ip, Elf32_Addr dest, u32 maskbits, int shift) +{ + u32 opcode; + long ep = (long)ip & ~31; + long delta = ((long)dest - ep) >> 2; + long mask = (1 << maskbits) - 1; + + if ((delta >> (maskbits - 1)) == 0 || + (delta >> (maskbits - 1)) == -1) { + opcode = *ip; + opcode &= ~(mask << shift); + opcode |= ((delta & mask) << shift); + *ip = opcode; + + pr_debug("REL PCR_S%d[%p] dest[%p] opcode[%08x]\n", + maskbits, ip, (void *)dest, opcode); + + return 0; + } + pr_err("PCR_S%d reloc %p -> %p out of range!\n", + maskbits, ip, (void *)dest); + + return -1; +} + +/* + * apply a RELA relocation + */ +int apply_relocate_add(Elf32_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, + unsigned int relsec, + struct module *me) +{ + Elf32_Rela *rel = (void *) sechdrs[relsec].sh_addr; + Elf_Sym *sym; + u32 *location, opcode; + unsigned int i; + Elf32_Addr v; + Elf_Addr offset = 0; + + pr_debug("Applying relocate section %u to %u with offset 0x%x\n", + relsec, sechdrs[relsec].sh_info, offset); + + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + /* This is where to make the change */ + location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr + + rel[i].r_offset - offset; + + /* This is the symbol it is referring to. Note that all + undefined symbols have been resolved. */ + sym = (Elf_Sym *)sechdrs[symindex].sh_addr + + ELF32_R_SYM(rel[i].r_info); + + /* this is the adjustment to be made */ + v = sym->st_value + rel[i].r_addend; + + switch (ELF32_R_TYPE(rel[i].r_info)) { + case R_C6000_ABS32: + pr_debug("RELA ABS32: [%p] = 0x%x\n", location, v); + *location = v; + break; + case R_C6000_ABS16: + pr_debug("RELA ABS16: [%p] = 0x%x\n", location, v); + *(u16 *)location = v; + break; + case R_C6000_ABS8: + pr_debug("RELA ABS8: [%p] = 0x%x\n", location, v); + *(u8 *)location = v; + break; + case R_C6000_ABS_L16: + opcode = *location; + opcode &= ~0x7fff80; + opcode |= ((v & 0xffff) << 7); + pr_debug("RELA ABS_L16[%p] v[0x%x] opcode[0x%x]\n", + location, v, opcode); + *location = opcode; + break; + case R_C6000_ABS_H16: + opcode = *location; + opcode &= ~0x7fff80; + opcode |= ((v >> 9) & 0x7fff80); + pr_debug("RELA ABS_H16[%p] v[0x%x] opcode[0x%x]\n", + location, v, opcode); + *location = opcode; + break; + case R_C6000_PCR_S21: + if (fixup_pcr(location, v, 21, 7)) + return -ENOEXEC; + break; + case R_C6000_PCR_S12: + if (fixup_pcr(location, v, 12, 16)) + return -ENOEXEC; + break; + case R_C6000_PCR_S10: + if (fixup_pcr(location, v, 10, 13)) + return -ENOEXEC; + break; + default: + pr_err("module %s: Unknown RELA relocation: %u\n", + me->name, ELF32_R_TYPE(rel[i].r_info)); + return -ENOEXEC; + } + } + + return 0; +} |