| Guo Ren | 9d056df | 2018-09-05 14:25:16 +0800 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. |
| 3 | |
| 4 | #include <linux/moduleloader.h> |
| 5 | #include <linux/elf.h> |
| 6 | #include <linux/mm.h> |
| 7 | #include <linux/vmalloc.h> |
| 8 | #include <linux/slab.h> |
| 9 | #include <linux/fs.h> |
| 10 | #include <linux/string.h> |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/spinlock.h> |
| 13 | #include <asm/pgtable.h> |
| 14 | |
| 15 | #if defined(__CSKYABIV2__) |
| 16 | #define IS_BSR32(hi16, lo16) (((hi16) & 0xFC00) == 0xE000) |
| 17 | #define IS_JSRI32(hi16, lo16) ((hi16) == 0xEAE0) |
| 18 | |
| 19 | #define CHANGE_JSRI_TO_LRW(addr) do { \ |
| 20 | *(uint16_t *)(addr) = (*(uint16_t *)(addr) & 0xFF9F) | 0x001a; \ |
| 21 | *((uint16_t *)(addr) + 1) = *((uint16_t *)(addr) + 1) & 0xFFFF; \ |
| 22 | } while (0) |
| 23 | |
| 24 | #define SET_JSR32_R26(addr) do { \ |
| 25 | *(uint16_t *)(addr) = 0xE8Fa; \ |
| 26 | *((uint16_t *)(addr) + 1) = 0x0000; \ |
| 27 | } while (0) |
| 28 | #endif |
| 29 | |
| 30 | int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab, |
| 31 | unsigned int symindex, unsigned int relsec, struct module *me) |
| 32 | { |
| 33 | unsigned int i; |
| 34 | Elf32_Rela *rel = (void *) sechdrs[relsec].sh_addr; |
| 35 | Elf32_Sym *sym; |
| 36 | uint32_t *location; |
| 37 | short *temp; |
| 38 | #if defined(__CSKYABIV2__) |
| 39 | uint16_t *location_tmp; |
| 40 | #endif |
| 41 | |
| 42 | for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { |
| 43 | /* This is where to make the change */ |
| 44 | location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr |
| 45 | + rel[i].r_offset; |
| 46 | sym = (Elf32_Sym *)sechdrs[symindex].sh_addr |
| 47 | + ELF32_R_SYM(rel[i].r_info); |
| 48 | |
| 49 | switch (ELF32_R_TYPE(rel[i].r_info)) { |
| 50 | case R_CSKY_32: |
| 51 | /* We add the value into the location given */ |
| 52 | *location = rel[i].r_addend + sym->st_value; |
| 53 | break; |
| 54 | case R_CSKY_PC32: |
| 55 | /* Add the value, subtract its postition */ |
| 56 | *location = rel[i].r_addend + sym->st_value |
| 57 | - (uint32_t)location; |
| 58 | break; |
| 59 | case R_CSKY_PCRELJSR_IMM11BY2: |
| 60 | break; |
| 61 | case R_CSKY_PCRELJSR_IMM26BY2: |
| 62 | #if defined(__CSKYABIV2__) |
| 63 | location_tmp = (uint16_t *)location; |
| 64 | if (IS_BSR32(*location_tmp, *(location_tmp + 1))) |
| 65 | break; |
| 66 | |
| 67 | if (IS_JSRI32(*location_tmp, *(location_tmp + 1))) { |
| 68 | /* jsri 0x... --> lrw r26, 0x... */ |
| 69 | CHANGE_JSRI_TO_LRW(location); |
| 70 | /* lsli r0, r0 --> jsr r26 */ |
| 71 | SET_JSR32_R26(location + 1); |
| 72 | } |
| 73 | #endif |
| 74 | break; |
| 75 | case R_CSKY_ADDR_HI16: |
| 76 | temp = ((short *)location) + 1; |
| 77 | *temp = (short) |
| 78 | ((rel[i].r_addend + sym->st_value) >> 16); |
| 79 | break; |
| 80 | case R_CSKY_ADDR_LO16: |
| 81 | temp = ((short *)location) + 1; |
| 82 | *temp = (short) |
| 83 | ((rel[i].r_addend + sym->st_value) & 0xffff); |
| 84 | break; |
| 85 | default: |
| 86 | pr_err("module %s: Unknown relocation: %u\n", |
| 87 | me->name, ELF32_R_TYPE(rel[i].r_info)); |
| 88 | return -ENOEXEC; |
| 89 | } |
| 90 | } |
| 91 | return 0; |
| 92 | } |