1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * FPGA Manager Driver for Altera Arria10 SoCFPGA 4 * 5 * Copyright (C) 2015-2016 Altera Corporation 6 */ 7 #include <linux/clk.h> 8 #include <linux/device.h> 9 #include <linux/delay.h> 10 #include <linux/fpga/fpga-mgr.h> 11 #include <linux/io.h> 12 #include <linux/module.h> 13 #include <linux/of_address.h> 14 #include <linux/regmap.h> 15 16 #define A10_FPGAMGR_DCLKCNT_OFST 0x08 17 #define A10_FPGAMGR_DCLKSTAT_OFST 0x0c 18 #define A10_FPGAMGR_IMGCFG_CTL_00_OFST 0x70 19 #define A10_FPGAMGR_IMGCFG_CTL_01_OFST 0x74 20 #define A10_FPGAMGR_IMGCFG_CTL_02_OFST 0x78 21 #define A10_FPGAMGR_IMGCFG_STAT_OFST 0x80 22 23 #define A10_FPGAMGR_DCLKSTAT_DCLKDONE BIT(0) 24 25 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NCONFIG BIT(0) 26 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NSTATUS BIT(1) 27 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_CONDONE BIT(2) 28 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NCONFIG BIT(8) 29 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_NSTATUS_OE BIT(16) 30 #define A10_FPGAMGR_IMGCFG_CTL_00_S2F_CONDONE_OE BIT(24) 31 32 #define A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG BIT(0) 33 #define A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST BIT(16) 34 #define A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE BIT(24) 35 36 #define A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL BIT(0) 37 #define A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_MASK (BIT(16) | BIT(17)) 38 #define A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_SHIFT 16 39 #define A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH BIT(24) 40 #define A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH_SHIFT 24 41 42 #define A10_FPGAMGR_IMGCFG_STAT_F2S_CRC_ERROR BIT(0) 43 #define A10_FPGAMGR_IMGCFG_STAT_F2S_EARLY_USERMODE BIT(1) 44 #define A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE BIT(2) 45 #define A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN BIT(4) 46 #define A10_FPGAMGR_IMGCFG_STAT_F2S_CONDONE_PIN BIT(6) 47 #define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY BIT(9) 48 #define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_DONE BIT(10) 49 #define A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR BIT(11) 50 #define A10_FPGAMGR_IMGCFG_STAT_F2S_NCONFIG_PIN BIT(12) 51 #define A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_MASK (BIT(16) | BIT(17) | BIT(18)) 52 #define A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_SHIFT 16 53 54 /* FPGA CD Ratio Value */ 55 #define CDRATIO_x1 0x0 56 #define CDRATIO_x2 0x1 57 #define CDRATIO_x4 0x2 58 #define CDRATIO_x8 0x3 59 60 /* Configuration width 16/32 bit */ 61 #define CFGWDTH_32 1 62 #define CFGWDTH_16 0 63 64 /* 65 * struct a10_fpga_priv - private data for fpga manager 66 * @regmap: regmap for register access 67 * @fpga_data_addr: iomap for single address data register to FPGA 68 * @clk: clock 69 */ 70 struct a10_fpga_priv { 71 struct regmap *regmap; 72 void __iomem *fpga_data_addr; 73 struct clk *clk; 74 }; 75 76 static bool socfpga_a10_fpga_writeable_reg(struct device *dev, unsigned int reg) 77 { 78 switch (reg) { 79 case A10_FPGAMGR_DCLKCNT_OFST: 80 case A10_FPGAMGR_DCLKSTAT_OFST: 81 case A10_FPGAMGR_IMGCFG_CTL_00_OFST: 82 case A10_FPGAMGR_IMGCFG_CTL_01_OFST: 83 case A10_FPGAMGR_IMGCFG_CTL_02_OFST: 84 return true; 85 } 86 return false; 87 } 88 89 static bool socfpga_a10_fpga_readable_reg(struct device *dev, unsigned int reg) 90 { 91 switch (reg) { 92 case A10_FPGAMGR_DCLKCNT_OFST: 93 case A10_FPGAMGR_DCLKSTAT_OFST: 94 case A10_FPGAMGR_IMGCFG_CTL_00_OFST: 95 case A10_FPGAMGR_IMGCFG_CTL_01_OFST: 96 case A10_FPGAMGR_IMGCFG_CTL_02_OFST: 97 case A10_FPGAMGR_IMGCFG_STAT_OFST: 98 return true; 99 } 100 return false; 101 } 102 103 static const struct regmap_config socfpga_a10_fpga_regmap_config = { 104 .reg_bits = 32, 105 .reg_stride = 4, 106 .val_bits = 32, 107 .writeable_reg = socfpga_a10_fpga_writeable_reg, 108 .readable_reg = socfpga_a10_fpga_readable_reg, 109 .max_register = A10_FPGAMGR_IMGCFG_STAT_OFST, 110 .cache_type = REGCACHE_NONE, 111 }; 112 113 /* 114 * from the register map description of cdratio in imgcfg_ctrl_02: 115 * Normal Configuration : 32bit Passive Parallel 116 * Partial Reconfiguration : 16bit Passive Parallel 117 */ 118 static void socfpga_a10_fpga_set_cfg_width(struct a10_fpga_priv *priv, 119 int width) 120 { 121 width <<= A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH_SHIFT; 122 123 regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST, 124 A10_FPGAMGR_IMGCFG_CTL_02_CFGWIDTH, width); 125 } 126 127 static void socfpga_a10_fpga_generate_dclks(struct a10_fpga_priv *priv, 128 u32 count) 129 { 130 u32 val; 131 132 /* Clear any existing DONE status. */ 133 regmap_write(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST, 134 A10_FPGAMGR_DCLKSTAT_DCLKDONE); 135 136 /* Issue the DCLK regmap. */ 137 regmap_write(priv->regmap, A10_FPGAMGR_DCLKCNT_OFST, count); 138 139 /* wait till the dclkcnt done */ 140 regmap_read_poll_timeout(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST, val, 141 val, 1, 100); 142 143 /* Clear DONE status. */ 144 regmap_write(priv->regmap, A10_FPGAMGR_DCLKSTAT_OFST, 145 A10_FPGAMGR_DCLKSTAT_DCLKDONE); 146 } 147 148 #define RBF_ENCRYPTION_MODE_OFFSET 69 149 #define RBF_DECOMPRESS_OFFSET 229 150 151 static int socfpga_a10_fpga_encrypted(u32 *buf32, size_t buf32_size) 152 { 153 if (buf32_size < RBF_ENCRYPTION_MODE_OFFSET + 1) 154 return -EINVAL; 155 156 /* Is the bitstream encrypted? */ 157 return ((buf32[RBF_ENCRYPTION_MODE_OFFSET] >> 2) & 3) != 0; 158 } 159 160 static int socfpga_a10_fpga_compressed(u32 *buf32, size_t buf32_size) 161 { 162 if (buf32_size < RBF_DECOMPRESS_OFFSET + 1) 163 return -EINVAL; 164 165 /* Is the bitstream compressed? */ 166 return !((buf32[RBF_DECOMPRESS_OFFSET] >> 1) & 1); 167 } 168 169 static unsigned int socfpga_a10_fpga_get_cd_ratio(unsigned int cfg_width, 170 bool encrypt, bool compress) 171 { 172 unsigned int cd_ratio; 173 174 /* 175 * cd ratio is dependent on cfg width and whether the bitstream 176 * is encrypted and/or compressed. 177 * 178 * | width | encr. | compr. | cd ratio | 179 * | 16 | 0 | 0 | 1 | 180 * | 16 | 0 | 1 | 4 | 181 * | 16 | 1 | 0 | 2 | 182 * | 16 | 1 | 1 | 4 | 183 * | 32 | 0 | 0 | 1 | 184 * | 32 | 0 | 1 | 8 | 185 * | 32 | 1 | 0 | 4 | 186 * | 32 | 1 | 1 | 8 | 187 */ 188 if (!compress && !encrypt) 189 return CDRATIO_x1; 190 191 if (compress) 192 cd_ratio = CDRATIO_x4; 193 else 194 cd_ratio = CDRATIO_x2; 195 196 /* If 32 bit, double the cd ratio by incrementing the field */ 197 if (cfg_width == CFGWDTH_32) 198 cd_ratio += 1; 199 200 return cd_ratio; 201 } 202 203 static int socfpga_a10_fpga_set_cdratio(struct fpga_manager *mgr, 204 unsigned int cfg_width, 205 const char *buf, size_t count) 206 { 207 struct a10_fpga_priv *priv = mgr->priv; 208 unsigned int cd_ratio; 209 int encrypt, compress; 210 211 encrypt = socfpga_a10_fpga_encrypted((u32 *)buf, count / 4); 212 if (encrypt < 0) 213 return -EINVAL; 214 215 compress = socfpga_a10_fpga_compressed((u32 *)buf, count / 4); 216 if (compress < 0) 217 return -EINVAL; 218 219 cd_ratio = socfpga_a10_fpga_get_cd_ratio(cfg_width, encrypt, compress); 220 221 regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST, 222 A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_MASK, 223 cd_ratio << A10_FPGAMGR_IMGCFG_CTL_02_CDRATIO_SHIFT); 224 225 return 0; 226 } 227 228 static u32 socfpga_a10_fpga_read_stat(struct a10_fpga_priv *priv) 229 { 230 u32 val; 231 232 regmap_read(priv->regmap, A10_FPGAMGR_IMGCFG_STAT_OFST, &val); 233 234 return val; 235 } 236 237 static int socfpga_a10_fpga_wait_for_pr_ready(struct a10_fpga_priv *priv) 238 { 239 u32 reg, i; 240 241 for (i = 0; i < 10 ; i++) { 242 reg = socfpga_a10_fpga_read_stat(priv); 243 244 if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR) 245 return -EINVAL; 246 247 if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY) 248 return 0; 249 } 250 251 return -ETIMEDOUT; 252 } 253 254 static int socfpga_a10_fpga_wait_for_pr_done(struct a10_fpga_priv *priv) 255 { 256 u32 reg, i; 257 258 for (i = 0; i < 10 ; i++) { 259 reg = socfpga_a10_fpga_read_stat(priv); 260 261 if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_ERROR) 262 return -EINVAL; 263 264 if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_DONE) 265 return 0; 266 } 267 268 return -ETIMEDOUT; 269 } 270 271 /* Start the FPGA programming by initialize the FPGA Manager */ 272 static int socfpga_a10_fpga_write_init(struct fpga_manager *mgr, 273 struct fpga_image_info *info, 274 const char *buf, size_t count) 275 { 276 struct a10_fpga_priv *priv = mgr->priv; 277 unsigned int cfg_width; 278 u32 msel, stat, mask; 279 int ret; 280 281 if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) 282 cfg_width = CFGWDTH_16; 283 else 284 return -EINVAL; 285 286 /* Check for passive parallel (msel == 000 or 001) */ 287 msel = socfpga_a10_fpga_read_stat(priv); 288 msel &= A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_MASK; 289 msel >>= A10_FPGAMGR_IMGCFG_STAT_F2S_MSEL_SHIFT; 290 if ((msel != 0) && (msel != 1)) { 291 dev_dbg(&mgr->dev, "Fail: invalid msel=%d\n", msel); 292 return -EINVAL; 293 } 294 295 /* Make sure no external devices are interfering */ 296 stat = socfpga_a10_fpga_read_stat(priv); 297 mask = A10_FPGAMGR_IMGCFG_STAT_F2S_NCONFIG_PIN | 298 A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN; 299 if ((stat & mask) != mask) 300 return -EINVAL; 301 302 /* Set cfg width */ 303 socfpga_a10_fpga_set_cfg_width(priv, cfg_width); 304 305 /* Determine cd ratio from bitstream header and set cd ratio */ 306 ret = socfpga_a10_fpga_set_cdratio(mgr, cfg_width, buf, count); 307 if (ret) 308 return ret; 309 310 /* 311 * Clear s2f_nce to enable chip select. Leave pr_request 312 * unasserted and override disabled. 313 */ 314 regmap_write(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST, 315 A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG); 316 317 /* Set cfg_ctrl to enable s2f dclk and data */ 318 regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST, 319 A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL, 320 A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL); 321 322 /* 323 * Disable overrides not needed for pr. 324 * s2f_config==1 leaves reset deasseted. 325 */ 326 regmap_write(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_00_OFST, 327 A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NCONFIG | 328 A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_NSTATUS | 329 A10_FPGAMGR_IMGCFG_CTL_00_S2F_NENABLE_CONDONE | 330 A10_FPGAMGR_IMGCFG_CTL_00_S2F_NCONFIG); 331 332 /* Enable override for data, dclk, nce, and pr_request to CSS */ 333 regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST, 334 A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG, 0); 335 336 /* Send some clocks to clear out any errors */ 337 socfpga_a10_fpga_generate_dclks(priv, 256); 338 339 /* Assert pr_request */ 340 regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST, 341 A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST, 342 A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST); 343 344 /* Provide 2048 DCLKs before starting the config data streaming. */ 345 socfpga_a10_fpga_generate_dclks(priv, 0x7ff); 346 347 /* Wait for pr_ready */ 348 return socfpga_a10_fpga_wait_for_pr_ready(priv); 349 } 350 351 /* 352 * write data to the FPGA data register 353 */ 354 static int socfpga_a10_fpga_write(struct fpga_manager *mgr, const char *buf, 355 size_t count) 356 { 357 struct a10_fpga_priv *priv = mgr->priv; 358 u32 *buffer_32 = (u32 *)buf; 359 size_t i = 0; 360 361 if (count <= 0) 362 return -EINVAL; 363 364 /* Write out the complete 32-bit chunks */ 365 while (count >= sizeof(u32)) { 366 writel(buffer_32[i++], priv->fpga_data_addr); 367 count -= sizeof(u32); 368 } 369 370 /* Write out remaining non 32-bit chunks */ 371 switch (count) { 372 case 3: 373 writel(buffer_32[i++] & 0x00ffffff, priv->fpga_data_addr); 374 break; 375 case 2: 376 writel(buffer_32[i++] & 0x0000ffff, priv->fpga_data_addr); 377 break; 378 case 1: 379 writel(buffer_32[i++] & 0x000000ff, priv->fpga_data_addr); 380 break; 381 case 0: 382 break; 383 default: 384 /* This will never happen */ 385 return -EFAULT; 386 } 387 388 return 0; 389 } 390 391 static int socfpga_a10_fpga_write_complete(struct fpga_manager *mgr, 392 struct fpga_image_info *info) 393 { 394 struct a10_fpga_priv *priv = mgr->priv; 395 u32 reg; 396 int ret; 397 398 /* Wait for pr_done */ 399 ret = socfpga_a10_fpga_wait_for_pr_done(priv); 400 401 /* Clear pr_request */ 402 regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST, 403 A10_FPGAMGR_IMGCFG_CTL_01_S2F_PR_REQUEST, 0); 404 405 /* Send some clocks to clear out any errors */ 406 socfpga_a10_fpga_generate_dclks(priv, 256); 407 408 /* Disable s2f dclk and data */ 409 regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_02_OFST, 410 A10_FPGAMGR_IMGCFG_CTL_02_EN_CFG_CTRL, 0); 411 412 /* Deassert chip select */ 413 regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST, 414 A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE, 415 A10_FPGAMGR_IMGCFG_CTL_01_S2F_NCE); 416 417 /* Disable data, dclk, nce, and pr_request override to CSS */ 418 regmap_update_bits(priv->regmap, A10_FPGAMGR_IMGCFG_CTL_01_OFST, 419 A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG, 420 A10_FPGAMGR_IMGCFG_CTL_01_S2F_NENABLE_CONFIG); 421 422 /* Return any errors regarding pr_done or pr_error */ 423 if (ret) 424 return ret; 425 426 /* Final check */ 427 reg = socfpga_a10_fpga_read_stat(priv); 428 429 if (((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE) == 0) || 430 ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_CONDONE_PIN) == 0) || 431 ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN) == 0)) { 432 dev_dbg(&mgr->dev, 433 "Timeout in final check. Status=%08xf\n", reg); 434 return -ETIMEDOUT; 435 } 436 437 return 0; 438 } 439 440 static enum fpga_mgr_states socfpga_a10_fpga_state(struct fpga_manager *mgr) 441 { 442 struct a10_fpga_priv *priv = mgr->priv; 443 u32 reg = socfpga_a10_fpga_read_stat(priv); 444 445 if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_USERMODE) 446 return FPGA_MGR_STATE_OPERATING; 447 448 if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_PR_READY) 449 return FPGA_MGR_STATE_WRITE; 450 451 if (reg & A10_FPGAMGR_IMGCFG_STAT_F2S_CRC_ERROR) 452 return FPGA_MGR_STATE_WRITE_COMPLETE_ERR; 453 454 if ((reg & A10_FPGAMGR_IMGCFG_STAT_F2S_NSTATUS_PIN) == 0) 455 return FPGA_MGR_STATE_RESET; 456 457 return FPGA_MGR_STATE_UNKNOWN; 458 } 459 460 static const struct fpga_manager_ops socfpga_a10_fpga_mgr_ops = { 461 .initial_header_size = (RBF_DECOMPRESS_OFFSET + 1) * 4, 462 .state = socfpga_a10_fpga_state, 463 .write_init = socfpga_a10_fpga_write_init, 464 .write = socfpga_a10_fpga_write, 465 .write_complete = socfpga_a10_fpga_write_complete, 466 }; 467 468 static int socfpga_a10_fpga_probe(struct platform_device *pdev) 469 { 470 struct device *dev = &pdev->dev; 471 struct a10_fpga_priv *priv; 472 void __iomem *reg_base; 473 struct fpga_manager *mgr; 474 int ret; 475 476 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 477 if (!priv) 478 return -ENOMEM; 479 480 /* First mmio base is for register access */ 481 reg_base = devm_platform_ioremap_resource(pdev, 0); 482 if (IS_ERR(reg_base)) 483 return PTR_ERR(reg_base); 484 485 /* Second mmio base is for writing FPGA image data */ 486 priv->fpga_data_addr = devm_platform_ioremap_resource(pdev, 1); 487 if (IS_ERR(priv->fpga_data_addr)) 488 return PTR_ERR(priv->fpga_data_addr); 489 490 /* regmap for register access */ 491 priv->regmap = devm_regmap_init_mmio(dev, reg_base, 492 &socfpga_a10_fpga_regmap_config); 493 if (IS_ERR(priv->regmap)) 494 return -ENODEV; 495 496 priv->clk = devm_clk_get(dev, NULL); 497 if (IS_ERR(priv->clk)) { 498 dev_err(dev, "no clock specified\n"); 499 return PTR_ERR(priv->clk); 500 } 501 502 ret = clk_prepare_enable(priv->clk); 503 if (ret) { 504 dev_err(dev, "could not enable clock\n"); 505 return -EBUSY; 506 } 507 508 mgr = fpga_mgr_register(dev, "SoCFPGA Arria10 FPGA Manager", 509 &socfpga_a10_fpga_mgr_ops, priv); 510 if (IS_ERR(mgr)) { 511 clk_disable_unprepare(priv->clk); 512 return PTR_ERR(mgr); 513 } 514 515 platform_set_drvdata(pdev, mgr); 516 517 return 0; 518 } 519 520 static void socfpga_a10_fpga_remove(struct platform_device *pdev) 521 { 522 struct fpga_manager *mgr = platform_get_drvdata(pdev); 523 struct a10_fpga_priv *priv = mgr->priv; 524 525 fpga_mgr_unregister(mgr); 526 clk_disable_unprepare(priv->clk); 527 } 528 529 static const struct of_device_id socfpga_a10_fpga_of_match[] = { 530 { .compatible = "altr,socfpga-a10-fpga-mgr", }, 531 {}, 532 }; 533 534 MODULE_DEVICE_TABLE(of, socfpga_a10_fpga_of_match); 535 536 static struct platform_driver socfpga_a10_fpga_driver = { 537 .probe = socfpga_a10_fpga_probe, 538 .remove_new = socfpga_a10_fpga_remove, 539 .driver = { 540 .name = "socfpga_a10_fpga_manager", 541 .of_match_table = socfpga_a10_fpga_of_match, 542 }, 543 }; 544 545 module_platform_driver(socfpga_a10_fpga_driver); 546 547 MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>"); 548 MODULE_DESCRIPTION("SoCFPGA Arria10 FPGA Manager"); 549 MODULE_LICENSE("GPL v2"); 550