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 } 93