| 1 | /* |
| 2 | * arch/ubicom32/kernel/flat.c |
| 3 | * Ubicom32 architecture flat executable format support. |
| 4 | * |
| 5 | * (C) Copyright 2009, Ubicom, Inc. |
| 6 | * |
| 7 | * This file is part of the Ubicom32 Linux Kernel Port. |
| 8 | * |
| 9 | * The Ubicom32 Linux Kernel Port is free software: you can redistribute |
| 10 | * it and/or modify it under the terms of the GNU General Public License |
| 11 | * as published by the Free Software Foundation, either version 2 of the |
| 12 | * License, or (at your option) any later version. |
| 13 | * |
| 14 | * The Ubicom32 Linux Kernel Port is distributed in the hope that it |
| 15 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
| 16 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 17 | * the GNU General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU General Public License |
| 20 | * along with the Ubicom32 Linux Kernel Port. If not, |
| 21 | * see <http://www.gnu.org/licenses/>. |
| 22 | * |
| 23 | * Ubicom32 implementation derived from (with many thanks): |
| 24 | * arch/m68knommu |
| 25 | * arch/blackfin |
| 26 | * arch/parisc |
| 27 | */ |
| 28 | #include <linux/module.h> |
| 29 | #include <linux/types.h> |
| 30 | #include <linux/flat.h> |
| 31 | |
| 32 | unsigned long ubicom32_flat_get_addr_from_rp(unsigned long *rp, |
| 33 | u32_t relval, |
| 34 | u32_t flags, |
| 35 | unsigned long *persistent) |
| 36 | { |
| 37 | u32_t relval_reloc_type = relval >> 27; |
| 38 | u32_t insn = *rp; |
| 39 | |
| 40 | if (*persistent) { |
| 41 | /* |
| 42 | * relval holds the relocation that has to be adjusted. |
| 43 | */ |
| 44 | if (relval == 0) { |
| 45 | *persistent = 0; |
| 46 | } |
| 47 | |
| 48 | return relval; |
| 49 | } |
| 50 | |
| 51 | if (relval_reloc_type == R_UBICOM32_32) { |
| 52 | /* |
| 53 | * insn holds the relocation |
| 54 | */ |
| 55 | return insn; |
| 56 | } |
| 57 | |
| 58 | /* |
| 59 | * We don't know this one. |
| 60 | */ |
| 61 | return 0; |
| 62 | } |
| 63 | |
| 64 | void ubicom32_flat_put_addr_at_rp(unsigned long *rp, |
| 65 | u32_t val, |
| 66 | u32_t relval, |
| 67 | unsigned long *persistent) |
| 68 | { |
| 69 | u32_t reloc_type = (relval >> 27) & 0x1f; |
| 70 | u32_t insn = *rp; |
| 71 | |
| 72 | /* |
| 73 | * If persistent is set then it contains the relocation type. |
| 74 | */ |
| 75 | if (*persistent) { |
| 76 | /* |
| 77 | * If persistent is set then it contains the relocation type. |
| 78 | */ |
| 79 | reloc_type = (*persistent >> 27) & 0x1f; |
| 80 | } |
| 81 | |
| 82 | switch (reloc_type) { |
| 83 | case R_UBICOM32_32: |
| 84 | /* |
| 85 | * Store the 32 bits as is. |
| 86 | */ |
| 87 | *rp = val; |
| 88 | break; |
| 89 | case R_UBICOM32_HI24: |
| 90 | { |
| 91 | /* |
| 92 | * 24 bit relocation that is part of the MOVEAI |
| 93 | * instruction. The 24 bits come from bits 7 - 30 of the |
| 94 | * relocation. The 24 bits eventually get split into 2 |
| 95 | * fields in the instruction encoding. |
| 96 | * |
| 97 | * - Bits 7 - 27 of the relocation are encoded into bits |
| 98 | * 0 - 20 of the instruction. |
| 99 | * |
| 100 | * - Bits 28 - 30 of the relocation are encoded into bit |
| 101 | * 24 - 26 of the instruction. |
| 102 | */ |
| 103 | u32_t mask = 0x1fffff | (0x7 << 24); |
| 104 | u32_t valid24bits = (val >> 7) & 0xffffff; |
| 105 | u32_t bot_21 = valid24bits & 0x1fffff; |
| 106 | u32_t upper_3_bits = ((valid24bits & 0xe00000) << 3); |
| 107 | insn &= ~mask; |
| 108 | |
| 109 | insn |= bot_21; |
| 110 | insn |= upper_3_bits; |
| 111 | *rp = insn; |
| 112 | } |
| 113 | break; |
| 114 | case R_UBICOM32_LO7_S: |
| 115 | case R_UBICOM32_LO7_2_S: |
| 116 | case R_UBICOM32_LO7_4_S: |
| 117 | { |
| 118 | /* |
| 119 | * Bits 0 - 6 of the relocation are encoded into the |
| 120 | * 7bit unsigned immediate fields of the SOURCE-1 field |
| 121 | * of the instruction. The immediate value is left |
| 122 | * shifted by (0, 1, 2) based on the operand size. |
| 123 | */ |
| 124 | u32_t mask = 0x1f | (0x3 << 8); |
| 125 | u32_t bottom, top; |
| 126 | val &= 0x7f; |
| 127 | if (reloc_type == R_UBICOM32_LO7_2_S) { |
| 128 | val >>= 1; |
| 129 | } else if (reloc_type == R_UBICOM32_LO7_4_S) { |
| 130 | val >>= 2; |
| 131 | } |
| 132 | |
| 133 | bottom = val & 0x1f; |
| 134 | top = val >> 5; |
| 135 | insn &= ~mask; |
| 136 | insn |= bottom; |
| 137 | insn |= (top << 8); |
| 138 | BUG_ON(*rp != insn); |
| 139 | *rp = insn; |
| 140 | break; |
| 141 | } |
| 142 | case R_UBICOM32_LO7_D: |
| 143 | case R_UBICOM32_LO7_2_D: |
| 144 | case R_UBICOM32_LO7_4_D: |
| 145 | { |
| 146 | /* |
| 147 | * Bits 0 - 6 of the relocation are encoded into the |
| 148 | * 7bit unsigned immediate fields of the DESTINATION |
| 149 | * field of the instruction. The immediate value is |
| 150 | * left shifted by (0, 1, 2) based on the operand size. |
| 151 | */ |
| 152 | u32_t mask = (0x1f | (0x3 << 8)) << 16; |
| 153 | u32_t bottom, top; |
| 154 | val &= 0x7f; |
| 155 | if (reloc_type == R_UBICOM32_LO7_2_D) { |
| 156 | val >>= 1; |
| 157 | } else if (reloc_type == R_UBICOM32_LO7_4_D) { |
| 158 | val >>= 2; |
| 159 | } |
| 160 | bottom = (val & 0x1f) << 16; |
| 161 | top = (val >> 5) << 16; |
| 162 | insn &= ~mask; |
| 163 | insn |= bottom; |
| 164 | insn |= (top << 8); |
| 165 | BUG_ON(*rp != insn); |
| 166 | *rp = insn; |
| 167 | break; |
| 168 | } |
| 169 | case R_UBICOM32_LO7_CALLI: |
| 170 | case R_UBICOM32_LO16_CALLI: |
| 171 | { |
| 172 | /* |
| 173 | * Extract the offset for a CALLI instruction. The |
| 174 | * offsets can be either 7 bits or 18 bits. Since all |
| 175 | * instructions in ubicom32 architecture are at work |
| 176 | * aligned addresses the truncated offset is right |
| 177 | * shifted by 2 before being encoded in the instruction. |
| 178 | */ |
| 179 | if (reloc_type == R_UBICOM32_LO7_CALLI) { |
| 180 | val &= 0x7f; |
| 181 | } else { |
| 182 | val &= 0x3ffff; |
| 183 | } |
| 184 | |
| 185 | val >>= 2; |
| 186 | |
| 187 | insn &= ~0x071f071f; |
| 188 | insn |= (val & 0x1f) << 0; |
| 189 | val >>= 5; |
| 190 | insn |= (val & 0x07) << 8; |
| 191 | val >>= 3; |
| 192 | insn |= (val & 0x1f) << 16; |
| 193 | val >>= 5; |
| 194 | insn |= (val & 0x07) << 24; |
| 195 | if (reloc_type == R_UBICOM32_LO7_CALLI) { |
| 196 | BUG_ON(*rp != insn); |
| 197 | } |
| 198 | *rp = insn; |
| 199 | } |
| 200 | break; |
| 201 | } |
| 202 | |
| 203 | if (*persistent) { |
| 204 | *persistent = 0; |
| 205 | } |
| 206 | } |
| 207 | |
