1 /***********************license start*************** 2 * Author: Cavium Networks 3 * 4 * Contact: support@caviumnetworks.com 5 * This file is part of the OCTEON SDK 6 * 7 * Copyright (C) 2003-2018 Cavium, Inc. 8 * 9 * This file is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License, Version 2, as 11 * published by the Free Software Foundation. 12 * 13 * This file is distributed in the hope that it will be useful, but 14 * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty 15 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or 16 * NONINFRINGEMENT. See the GNU General Public License for more 17 * details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this file; if not, write to the Free Software 21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 22 * or visit http://www.gnu.org/licenses/. 23 * 24 * This file may also be available under a different license from Cavium. 25 * Contact Cavium Networks for more information 26 ***********************license end**************************************/ 27 28 /* 29 * Functions for RGMII/GMII/MII initialization, configuration, 30 * and monitoring. 31 */ 32 #include <asm/octeon/octeon.h> 33 34 #include <asm/octeon/cvmx-config.h> 35 36 #include <asm/octeon/cvmx-pko.h> 37 #include <asm/octeon/cvmx-helper.h> 38 #include <asm/octeon/cvmx-helper-board.h> 39 40 #include <asm/octeon/cvmx-npi-defs.h> 41 #include <asm/octeon/cvmx-gmxx-defs.h> 42 #include <asm/octeon/cvmx-asxx-defs.h> 43 #include <asm/octeon/cvmx-dbg-defs.h> 44 45 /** 46 * Probe RGMII ports and determine the number present 47 * 48 * @interface: Interface to probe 49 * 50 * Returns Number of RGMII/GMII/MII ports (0-4). 51 */ 52 int __cvmx_helper_rgmii_probe(int interface) 53 { 54 int num_ports = 0; 55 union cvmx_gmxx_inf_mode mode; 56 mode.u64 = cvmx_read_csr(CVMX_GMXX_INF_MODE(interface)); 57 58 if (mode.s.type) { 59 if (OCTEON_IS_MODEL(OCTEON_CN38XX) 60 || OCTEON_IS_MODEL(OCTEON_CN58XX)) { 61 cvmx_dprintf("ERROR: RGMII initialize called in " 62 "SPI interface\n"); 63 } else if (OCTEON_IS_MODEL(OCTEON_CN31XX) 64 || OCTEON_IS_MODEL(OCTEON_CN30XX) 65 || OCTEON_IS_MODEL(OCTEON_CN50XX)) { 66 /* 67 * On these chips "type" says we're in 68 * GMII/MII mode. This limits us to 2 ports 69 */ 70 num_ports = 2; 71 } else { 72 cvmx_dprintf("ERROR: Unsupported Octeon model in %s\n", 73 __func__); 74 } 75 } else { 76 if (OCTEON_IS_MODEL(OCTEON_CN38XX) 77 || OCTEON_IS_MODEL(OCTEON_CN58XX)) { 78 num_ports = 4; 79 } else if (OCTEON_IS_MODEL(OCTEON_CN31XX) 80 || OCTEON_IS_MODEL(OCTEON_CN30XX) 81 || OCTEON_IS_MODEL(OCTEON_CN50XX)) { 82 num_ports = 3; 83 } else { 84 cvmx_dprintf("ERROR: Unsupported Octeon model in %s\n", 85 __func__); 86 } 87 } 88 return num_ports; 89 } 90 91 /** 92 * Put an RGMII interface in loopback mode. Internal packets sent 93 * out will be received back again on the same port. Externally 94 * received packets will echo back out. 95 * 96 * @port: IPD port number to loop. 97 */ 98 void cvmx_helper_rgmii_internal_loopback(int port) 99 { 100 int interface = (port >> 4) & 1; 101 int index = port & 0xf; 102 uint64_t tmp; 103 104 union cvmx_gmxx_prtx_cfg gmx_cfg; 105 gmx_cfg.u64 = 0; 106 gmx_cfg.s.duplex = 1; 107 gmx_cfg.s.slottime = 1; 108 gmx_cfg.s.speed = 1; 109 cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 1); 110 cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x200); 111 cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0x2000); 112 cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64); 113 tmp = cvmx_read_csr(CVMX_ASXX_PRT_LOOP(interface)); 114 cvmx_write_csr(CVMX_ASXX_PRT_LOOP(interface), (1 << index) | tmp); 115 tmp = cvmx_read_csr(CVMX_ASXX_TX_PRT_EN(interface)); 116 cvmx_write_csr(CVMX_ASXX_TX_PRT_EN(interface), (1 << index) | tmp); 117 tmp = cvmx_read_csr(CVMX_ASXX_RX_PRT_EN(interface)); 118 cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface), (1 << index) | tmp); 119 gmx_cfg.s.en = 1; 120 cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64); 121 } 122 123 /** 124 * Workaround ASX setup errata with CN38XX pass1 125 * 126 * @interface: Interface to setup 127 * @port: Port to setup (0..3) 128 * @cpu_clock_hz: 129 * Chip frequency in Hertz 130 * 131 * Returns Zero on success, negative on failure 132 */ 133 static int __cvmx_helper_errata_asx_pass1(int interface, int port, 134 int cpu_clock_hz) 135 { 136 /* Set hi water mark as per errata GMX-4 */ 137 if (cpu_clock_hz >= 325000000 && cpu_clock_hz < 375000000) 138 cvmx_write_csr(CVMX_ASXX_TX_HI_WATERX(port, interface), 12); 139 else if (cpu_clock_hz >= 375000000 && cpu_clock_hz < 437000000) 140 cvmx_write_csr(CVMX_ASXX_TX_HI_WATERX(port, interface), 11); 141 else if (cpu_clock_hz >= 437000000 && cpu_clock_hz < 550000000) 142 cvmx_write_csr(CVMX_ASXX_TX_HI_WATERX(port, interface), 10); 143 else if (cpu_clock_hz >= 550000000 && cpu_clock_hz < 687000000) 144 cvmx_write_csr(CVMX_ASXX_TX_HI_WATERX(port, interface), 9); 145 else 146 cvmx_dprintf("Illegal clock frequency (%d). " 147 "CVMX_ASXX_TX_HI_WATERX not set\n", cpu_clock_hz); 148 return 0; 149 } 150 151 /** 152 * Configure all of the ASX, GMX, and PKO registers required 153 * to get RGMII to function on the supplied interface. 154 * 155 * @interface: PKO Interface to configure (0 or 1) 156 * 157 * Returns Zero on success 158 */ 159 int __cvmx_helper_rgmii_enable(int interface) 160 { 161 int num_ports = cvmx_helper_ports_on_interface(interface); 162 int port; 163 struct cvmx_sysinfo *sys_info_ptr = cvmx_sysinfo_get(); 164 union cvmx_gmxx_inf_mode mode; 165 union cvmx_asxx_tx_prt_en asx_tx; 166 union cvmx_asxx_rx_prt_en asx_rx; 167 168 mode.u64 = cvmx_read_csr(CVMX_GMXX_INF_MODE(interface)); 169 170 if (mode.s.en == 0) 171 return -1; 172 if ((OCTEON_IS_MODEL(OCTEON_CN38XX) || 173 OCTEON_IS_MODEL(OCTEON_CN58XX)) && mode.s.type == 1) 174 /* Ignore SPI interfaces */ 175 return -1; 176 177 /* Configure the ASX registers needed to use the RGMII ports */ 178 asx_tx.u64 = 0; 179 asx_tx.s.prt_en = cvmx_build_mask(num_ports); 180 cvmx_write_csr(CVMX_ASXX_TX_PRT_EN(interface), asx_tx.u64); 181 182 asx_rx.u64 = 0; 183 asx_rx.s.prt_en = cvmx_build_mask(num_ports); 184 cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface), asx_rx.u64); 185 186 /* Configure the GMX registers needed to use the RGMII ports */ 187 for (port = 0; port < num_ports; port++) { 188 /* Setting of CVMX_GMXX_TXX_THRESH has been moved to 189 __cvmx_helper_setup_gmx() */ 190 191 if (cvmx_octeon_is_pass1()) 192 __cvmx_helper_errata_asx_pass1(interface, port, 193 sys_info_ptr-> 194 cpu_clock_hz); 195 else { 196 /* 197 * Configure more flexible RGMII preamble 198 * checking. Pass 1 doesn't support this 199 * feature. 200 */ 201 union cvmx_gmxx_rxx_frm_ctl frm_ctl; 202 frm_ctl.u64 = 203 cvmx_read_csr(CVMX_GMXX_RXX_FRM_CTL 204 (port, interface)); 205 /* New field, so must be compile time */ 206 frm_ctl.s.pre_free = 1; 207 cvmx_write_csr(CVMX_GMXX_RXX_FRM_CTL(port, interface), 208 frm_ctl.u64); 209 } 210 211 /* 212 * Each pause frame transmitted will ask for about 10M 213 * bit times before resume. If buffer space comes 214 * available before that time has expired, an XON 215 * pause frame (0 time) will be transmitted to restart 216 * the flow. 217 */ 218 cvmx_write_csr(CVMX_GMXX_TXX_PAUSE_PKT_TIME(port, interface), 219 20000); 220 cvmx_write_csr(CVMX_GMXX_TXX_PAUSE_PKT_INTERVAL 221 (port, interface), 19000); 222 223 if (OCTEON_IS_MODEL(OCTEON_CN50XX)) { 224 cvmx_write_csr(CVMX_ASXX_TX_CLK_SETX(port, interface), 225 16); 226 cvmx_write_csr(CVMX_ASXX_RX_CLK_SETX(port, interface), 227 16); 228 } else { 229 cvmx_write_csr(CVMX_ASXX_TX_CLK_SETX(port, interface), 230 24); 231 cvmx_write_csr(CVMX_ASXX_RX_CLK_SETX(port, interface), 232 24); 233 } 234 } 235 236 __cvmx_helper_setup_gmx(interface, num_ports); 237 238 /* enable the ports now */ 239 for (port = 0; port < num_ports; port++) { 240 union cvmx_gmxx_prtx_cfg gmx_cfg; 241 242 gmx_cfg.u64 = 243 cvmx_read_csr(CVMX_GMXX_PRTX_CFG(port, interface)); 244 gmx_cfg.s.en = 1; 245 cvmx_write_csr(CVMX_GMXX_PRTX_CFG(port, interface), 246 gmx_cfg.u64); 247 } 248 __cvmx_interrupt_asxx_enable(interface); 249 __cvmx_interrupt_gmxx_enable(interface); 250 251 return 0; 252 } 253 254 /** 255 * Return the link state of an IPD/PKO port as returned by 256 * auto negotiation. The result of this function may not match 257 * Octeon's link config if auto negotiation has changed since 258 * the last call to cvmx_helper_link_set(). 259 * 260 * @ipd_port: IPD/PKO port to query 261 * 262 * Returns Link state 263 */ 264 cvmx_helper_link_info_t __cvmx_helper_rgmii_link_get(int ipd_port) 265 { 266 int interface = cvmx_helper_get_interface_num(ipd_port); 267 int index = cvmx_helper_get_interface_index_num(ipd_port); 268 union cvmx_asxx_prt_loop asxx_prt_loop; 269 270 asxx_prt_loop.u64 = cvmx_read_csr(CVMX_ASXX_PRT_LOOP(interface)); 271 if (asxx_prt_loop.s.int_loop & (1 << index)) { 272 /* Force 1Gbps full duplex on internal loopback */ 273 cvmx_helper_link_info_t result; 274 result.u64 = 0; 275 result.s.full_duplex = 1; 276 result.s.link_up = 1; 277 result.s.speed = 1000; 278 return result; 279 } else 280 return __cvmx_helper_board_link_get(ipd_port); 281 } 282 283 /** 284 * Configure an IPD/PKO port for the specified link state. This 285 * function does not influence auto negotiation at the PHY level. 286 * The passed link state must always match the link state returned 287 * by cvmx_helper_link_get(). 288 * 289 * @ipd_port: IPD/PKO port to configure 290 * @link_info: The new link state 291 * 292 * Returns Zero on success, negative on failure 293 */ 294 int __cvmx_helper_rgmii_link_set(int ipd_port, 295 cvmx_helper_link_info_t link_info) 296 { 297 int result = 0; 298 int interface = cvmx_helper_get_interface_num(ipd_port); 299 int index = cvmx_helper_get_interface_index_num(ipd_port); 300 union cvmx_gmxx_prtx_cfg original_gmx_cfg; 301 union cvmx_gmxx_prtx_cfg new_gmx_cfg; 302 union cvmx_pko_mem_queue_qos pko_mem_queue_qos; 303 union cvmx_pko_mem_queue_qos pko_mem_queue_qos_save[16]; 304 union cvmx_gmxx_tx_ovr_bp gmx_tx_ovr_bp; 305 union cvmx_gmxx_tx_ovr_bp gmx_tx_ovr_bp_save; 306 int i; 307 308 /* Ignore speed sets in the simulator */ 309 if (cvmx_sysinfo_get()->board_type == CVMX_BOARD_TYPE_SIM) 310 return 0; 311 312 /* Read the current settings so we know the current enable state */ 313 original_gmx_cfg.u64 = 314 cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface)); 315 new_gmx_cfg = original_gmx_cfg; 316 317 /* Disable the lowest level RX */ 318 cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface), 319 cvmx_read_csr(CVMX_ASXX_RX_PRT_EN(interface)) & 320 ~(1 << index)); 321 322 memset(pko_mem_queue_qos_save, 0, sizeof(pko_mem_queue_qos_save)); 323 /* Disable all queues so that TX should become idle */ 324 for (i = 0; i < cvmx_pko_get_num_queues(ipd_port); i++) { 325 int queue = cvmx_pko_get_base_queue(ipd_port) + i; 326 cvmx_write_csr(CVMX_PKO_REG_READ_IDX, queue); 327 pko_mem_queue_qos.u64 = cvmx_read_csr(CVMX_PKO_MEM_QUEUE_QOS); 328 pko_mem_queue_qos.s.pid = ipd_port; 329 pko_mem_queue_qos.s.qid = queue; 330 pko_mem_queue_qos_save[i] = pko_mem_queue_qos; 331 pko_mem_queue_qos.s.qos_mask = 0; 332 cvmx_write_csr(CVMX_PKO_MEM_QUEUE_QOS, pko_mem_queue_qos.u64); 333 } 334 335 /* Disable backpressure */ 336 gmx_tx_ovr_bp.u64 = cvmx_read_csr(CVMX_GMXX_TX_OVR_BP(interface)); 337 gmx_tx_ovr_bp_save = gmx_tx_ovr_bp; 338 gmx_tx_ovr_bp.s.bp &= ~(1 << index); 339 gmx_tx_ovr_bp.s.en |= 1 << index; 340 cvmx_write_csr(CVMX_GMXX_TX_OVR_BP(interface), gmx_tx_ovr_bp.u64); 341 cvmx_read_csr(CVMX_GMXX_TX_OVR_BP(interface)); 342 343 /* 344 * Poll the GMX state machine waiting for it to become 345 * idle. Preferably we should only change speed when it is 346 * idle. If it doesn't become idle we will still do the speed 347 * change, but there is a slight chance that GMX will 348 * lockup. 349 */ 350 cvmx_write_csr(CVMX_NPI_DBG_SELECT, 351 interface * 0x800 + index * 0x100 + 0x880); 352 CVMX_WAIT_FOR_FIELD64(CVMX_DBG_DATA, union cvmx_dbg_data, data & 7, 353 ==, 0, 10000); 354 CVMX_WAIT_FOR_FIELD64(CVMX_DBG_DATA, union cvmx_dbg_data, data & 0xf, 355 ==, 0, 10000); 356 357 /* Disable the port before we make any changes */ 358 new_gmx_cfg.s.en = 0; 359 cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), new_gmx_cfg.u64); 360 cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface)); 361 362 /* Set full/half duplex */ 363 if (cvmx_octeon_is_pass1()) 364 /* Half duplex is broken for 38XX Pass 1 */ 365 new_gmx_cfg.s.duplex = 1; 366 else if (!link_info.s.link_up) 367 /* Force full duplex on down links */ 368 new_gmx_cfg.s.duplex = 1; 369 else 370 new_gmx_cfg.s.duplex = link_info.s.full_duplex; 371 372 /* Set the link speed. Anything unknown is set to 1Gbps */ 373 if (link_info.s.speed == 10) { 374 new_gmx_cfg.s.slottime = 0; 375 new_gmx_cfg.s.speed = 0; 376 } else if (link_info.s.speed == 100) { 377 new_gmx_cfg.s.slottime = 0; 378 new_gmx_cfg.s.speed = 0; 379 } else { 380 new_gmx_cfg.s.slottime = 1; 381 new_gmx_cfg.s.speed = 1; 382 } 383 384 /* Adjust the clocks */ 385 if (link_info.s.speed == 10) { 386 cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 50); 387 cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x40); 388 cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0); 389 } else if (link_info.s.speed == 100) { 390 cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 5); 391 cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x40); 392 cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0); 393 } else { 394 cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 1); 395 cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x200); 396 cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0x2000); 397 } 398 399 if (OCTEON_IS_MODEL(OCTEON_CN30XX) || OCTEON_IS_MODEL(OCTEON_CN50XX)) { 400 if ((link_info.s.speed == 10) || (link_info.s.speed == 100)) { 401 union cvmx_gmxx_inf_mode mode; 402 mode.u64 = cvmx_read_csr(CVMX_GMXX_INF_MODE(interface)); 403 404 /* 405 * Port .en .type .p0mii Configuration 406 * ---- --- ----- ------ ----------------------------------------- 407 * X 0 X X All links are disabled. 408 * 0 1 X 0 Port 0 is RGMII 409 * 0 1 X 1 Port 0 is MII 410 * 1 1 0 X Ports 1 and 2 are configured as RGMII ports. 411 * 1 1 1 X Port 1: GMII/MII; Port 2: disabled. GMII or 412 * MII port is selected by GMX_PRT1_CFG[SPEED]. 413 */ 414 415 /* In MII mode, CLK_CNT = 1. */ 416 if (((index == 0) && (mode.s.p0mii == 1)) 417 || ((index != 0) && (mode.s.type == 1))) { 418 cvmx_write_csr(CVMX_GMXX_TXX_CLK 419 (index, interface), 1); 420 } 421 } 422 } 423 424 /* Do a read to make sure all setup stuff is complete */ 425 cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface)); 426 427 /* Save the new GMX setting without enabling the port */ 428 cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), new_gmx_cfg.u64); 429 430 /* Enable the lowest level RX */ 431 cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface), 432 cvmx_read_csr(CVMX_ASXX_RX_PRT_EN(interface)) | (1 << 433 index)); 434 435 /* Re-enable the TX path */ 436 for (i = 0; i < cvmx_pko_get_num_queues(ipd_port); i++) { 437 int queue = cvmx_pko_get_base_queue(ipd_port) + i; 438 cvmx_write_csr(CVMX_PKO_REG_READ_IDX, queue); 439 cvmx_write_csr(CVMX_PKO_MEM_QUEUE_QOS, 440 pko_mem_queue_qos_save[i].u64); 441 } 442 443 /* Restore backpressure */ 444 cvmx_write_csr(CVMX_GMXX_TX_OVR_BP(interface), gmx_tx_ovr_bp_save.u64); 445 446 /* Restore the GMX enable state. Port config is complete */ 447 new_gmx_cfg.s.en = original_gmx_cfg.s.en; 448 cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), new_gmx_cfg.u64); 449 450 return result; 451 } 452 453 /** 454 * Configure a port for internal and/or external loopback. Internal loopback 455 * causes packets sent by the port to be received by Octeon. External loopback 456 * causes packets received from the wire to sent out again. 457 * 458 * @ipd_port: IPD/PKO port to loopback. 459 * @enable_internal: 460 * Non zero if you want internal loopback 461 * @enable_external: 462 * Non zero if you want external loopback 463 * 464 * Returns Zero on success, negative on failure. 465 */ 466 int __cvmx_helper_rgmii_configure_loopback(int ipd_port, int enable_internal, 467 int enable_external) 468 { 469 int interface = cvmx_helper_get_interface_num(ipd_port); 470 int index = cvmx_helper_get_interface_index_num(ipd_port); 471 int original_enable; 472 union cvmx_gmxx_prtx_cfg gmx_cfg; 473 union cvmx_asxx_prt_loop asxx_prt_loop; 474 475 /* Read the current enable state and save it */ 476 gmx_cfg.u64 = cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface)); 477 original_enable = gmx_cfg.s.en; 478 /* Force port to be disabled */ 479 gmx_cfg.s.en = 0; 480 if (enable_internal) { 481 /* Force speed if we're doing internal loopback */ 482 gmx_cfg.s.duplex = 1; 483 gmx_cfg.s.slottime = 1; 484 gmx_cfg.s.speed = 1; 485 cvmx_write_csr(CVMX_GMXX_TXX_CLK(index, interface), 1); 486 cvmx_write_csr(CVMX_GMXX_TXX_SLOT(index, interface), 0x200); 487 cvmx_write_csr(CVMX_GMXX_TXX_BURST(index, interface), 0x2000); 488 } 489 cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64); 490 491 /* Set the loopback bits */ 492 asxx_prt_loop.u64 = cvmx_read_csr(CVMX_ASXX_PRT_LOOP(interface)); 493 if (enable_internal) 494 asxx_prt_loop.s.int_loop |= 1 << index; 495 else 496 asxx_prt_loop.s.int_loop &= ~(1 << index); 497 if (enable_external) 498 asxx_prt_loop.s.ext_loop |= 1 << index; 499 else 500 asxx_prt_loop.s.ext_loop &= ~(1 << index); 501 cvmx_write_csr(CVMX_ASXX_PRT_LOOP(interface), asxx_prt_loop.u64); 502 503 /* Force enables in internal loopback */ 504 if (enable_internal) { 505 uint64_t tmp; 506 tmp = cvmx_read_csr(CVMX_ASXX_TX_PRT_EN(interface)); 507 cvmx_write_csr(CVMX_ASXX_TX_PRT_EN(interface), 508 (1 << index) | tmp); 509 tmp = cvmx_read_csr(CVMX_ASXX_RX_PRT_EN(interface)); 510 cvmx_write_csr(CVMX_ASXX_RX_PRT_EN(interface), 511 (1 << index) | tmp); 512 original_enable = 1; 513 } 514 515 /* Restore the enable state */ 516 gmx_cfg.s.en = original_enable; 517 cvmx_write_csr(CVMX_GMXX_PRTX_CFG(index, interface), gmx_cfg.u64); 518 return 0; 519 } 520