1 /* 2 * Driver for the PSC of the Freescale MPC52xx PSCs configured as UARTs. 3 * 4 * FIXME According to the usermanual the status bits in the status register 5 * are only updated when the peripherals access the FIFO and not when the 6 * CPU access them. So since we use this bits to know when we stop writing 7 * and reading, they may not be updated in-time and a race condition may 8 * exists. But I haven't be able to prove this and I don't care. But if 9 * any problem arises, it might worth checking. The TX/RX FIFO Stats 10 * registers should be used in addition. 11 * Update: Actually, they seem updated ... At least the bits we use. 12 * 13 * 14 * Maintainer : Sylvain Munaut <tnt@246tNt.com> 15 * 16 * Some of the code has been inspired/copied from the 2.4 code written 17 * by Dale Farnsworth <dfarnsworth@mvista.com>. 18 * 19 * Copyright (C) 2008 Freescale Semiconductor Inc. 20 * John Rigby <jrigby@gmail.com> 21 * Added support for MPC5121 22 * Copyright (C) 2006 Secret Lab Technologies Ltd. 23 * Grant Likely <grant.likely@secretlab.ca> 24 * Copyright (C) 2004-2006 Sylvain Munaut <tnt@246tNt.com> 25 * Copyright (C) 2003 MontaVista, Software, Inc. 26 * 27 * This file is licensed under the terms of the GNU General Public License 28 * version 2. This program is licensed "as is" without any warranty of any 29 * kind, whether express or implied. 30 */ 31 32 #undef DEBUG 33 34 #include <linux/device.h> 35 #include <linux/module.h> 36 #include <linux/tty.h> 37 #include <linux/tty_flip.h> 38 #include <linux/serial.h> 39 #include <linux/sysrq.h> 40 #include <linux/console.h> 41 #include <linux/delay.h> 42 #include <linux/io.h> 43 #include <linux/of.h> 44 #include <linux/of_platform.h> 45 #include <linux/clk.h> 46 47 #include <asm/mpc52xx.h> 48 #include <asm/mpc52xx_psc.h> 49 50 #if defined(CONFIG_SERIAL_MPC52xx_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) 51 #define SUPPORT_SYSRQ 52 #endif 53 54 #include <linux/serial_core.h> 55 56 57 /* We've been assigned a range on the "Low-density serial ports" major */ 58 #define SERIAL_PSC_MAJOR 204 59 #define SERIAL_PSC_MINOR 148 60 61 62 #define ISR_PASS_LIMIT 256 /* Max number of iteration in the interrupt */ 63 64 65 static struct uart_port mpc52xx_uart_ports[MPC52xx_PSC_MAXNUM]; 66 /* Rem: - We use the read_status_mask as a shadow of 67 * psc->mpc52xx_psc_imr 68 * - It's important that is array is all zero on start as we 69 * use it to know if it's initialized or not ! If it's not sure 70 * it's cleared, then a memset(...,0,...) should be added to 71 * the console_init 72 */ 73 74 /* lookup table for matching device nodes to index numbers */ 75 static struct device_node *mpc52xx_uart_nodes[MPC52xx_PSC_MAXNUM]; 76 77 static void mpc52xx_uart_of_enumerate(void); 78 79 80 #define PSC(port) ((struct mpc52xx_psc __iomem *)((port)->membase)) 81 82 83 /* Forward declaration of the interruption handling routine */ 84 static irqreturn_t mpc52xx_uart_int(int irq, void *dev_id); 85 static irqreturn_t mpc5xxx_uart_process_int(struct uart_port *port); 86 87 88 /* Simple macro to test if a port is console or not. This one is taken 89 * for serial_core.c and maybe should be moved to serial_core.h ? */ 90 #ifdef CONFIG_SERIAL_CORE_CONSOLE 91 #define uart_console(port) \ 92 ((port)->cons && (port)->cons->index == (port)->line) 93 #else 94 #define uart_console(port) (0) 95 #endif 96 97 /* ======================================================================== */ 98 /* PSC fifo operations for isolating differences between 52xx and 512x */ 99 /* ======================================================================== */ 100 101 struct psc_ops { 102 void (*fifo_init)(struct uart_port *port); 103 int (*raw_rx_rdy)(struct uart_port *port); 104 int (*raw_tx_rdy)(struct uart_port *port); 105 int (*rx_rdy)(struct uart_port *port); 106 int (*tx_rdy)(struct uart_port *port); 107 int (*tx_empty)(struct uart_port *port); 108 void (*stop_rx)(struct uart_port *port); 109 void (*start_tx)(struct uart_port *port); 110 void (*stop_tx)(struct uart_port *port); 111 void (*rx_clr_irq)(struct uart_port *port); 112 void (*tx_clr_irq)(struct uart_port *port); 113 void (*write_char)(struct uart_port *port, unsigned char c); 114 unsigned char (*read_char)(struct uart_port *port); 115 void (*cw_disable_ints)(struct uart_port *port); 116 void (*cw_restore_ints)(struct uart_port *port); 117 unsigned int (*set_baudrate)(struct uart_port *port, 118 struct ktermios *new, 119 struct ktermios *old); 120 int (*clock)(struct uart_port *port, int enable); 121 int (*fifoc_init)(void); 122 void (*fifoc_uninit)(void); 123 void (*get_irq)(struct uart_port *, struct device_node *); 124 irqreturn_t (*handle_irq)(struct uart_port *port); 125 }; 126 127 /* setting the prescaler and divisor reg is common for all chips */ 128 static inline void mpc52xx_set_divisor(struct mpc52xx_psc __iomem *psc, 129 u16 prescaler, unsigned int divisor) 130 { 131 /* select prescaler */ 132 out_be16(&psc->mpc52xx_psc_clock_select, prescaler); 133 out_8(&psc->ctur, divisor >> 8); 134 out_8(&psc->ctlr, divisor & 0xff); 135 } 136 137 #ifdef CONFIG_PPC_MPC52xx 138 #define FIFO_52xx(port) ((struct mpc52xx_psc_fifo __iomem *)(PSC(port)+1)) 139 static void mpc52xx_psc_fifo_init(struct uart_port *port) 140 { 141 struct mpc52xx_psc __iomem *psc = PSC(port); 142 struct mpc52xx_psc_fifo __iomem *fifo = FIFO_52xx(port); 143 144 out_8(&fifo->rfcntl, 0x00); 145 out_be16(&fifo->rfalarm, 0x1ff); 146 out_8(&fifo->tfcntl, 0x07); 147 out_be16(&fifo->tfalarm, 0x80); 148 149 port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY; 150 out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask); 151 } 152 153 static int mpc52xx_psc_raw_rx_rdy(struct uart_port *port) 154 { 155 return in_be16(&PSC(port)->mpc52xx_psc_status) 156 & MPC52xx_PSC_SR_RXRDY; 157 } 158 159 static int mpc52xx_psc_raw_tx_rdy(struct uart_port *port) 160 { 161 return in_be16(&PSC(port)->mpc52xx_psc_status) 162 & MPC52xx_PSC_SR_TXRDY; 163 } 164 165 166 static int mpc52xx_psc_rx_rdy(struct uart_port *port) 167 { 168 return in_be16(&PSC(port)->mpc52xx_psc_isr) 169 & port->read_status_mask 170 & MPC52xx_PSC_IMR_RXRDY; 171 } 172 173 static int mpc52xx_psc_tx_rdy(struct uart_port *port) 174 { 175 return in_be16(&PSC(port)->mpc52xx_psc_isr) 176 & port->read_status_mask 177 & MPC52xx_PSC_IMR_TXRDY; 178 } 179 180 static int mpc52xx_psc_tx_empty(struct uart_port *port) 181 { 182 return in_be16(&PSC(port)->mpc52xx_psc_status) 183 & MPC52xx_PSC_SR_TXEMP; 184 } 185 186 static void mpc52xx_psc_start_tx(struct uart_port *port) 187 { 188 port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY; 189 out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask); 190 } 191 192 static void mpc52xx_psc_stop_tx(struct uart_port *port) 193 { 194 port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY; 195 out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask); 196 } 197 198 static void mpc52xx_psc_stop_rx(struct uart_port *port) 199 { 200 port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY; 201 out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask); 202 } 203 204 static void mpc52xx_psc_rx_clr_irq(struct uart_port *port) 205 { 206 } 207 208 static void mpc52xx_psc_tx_clr_irq(struct uart_port *port) 209 { 210 } 211 212 static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char c) 213 { 214 out_8(&PSC(port)->mpc52xx_psc_buffer_8, c); 215 } 216 217 static unsigned char mpc52xx_psc_read_char(struct uart_port *port) 218 { 219 return in_8(&PSC(port)->mpc52xx_psc_buffer_8); 220 } 221 222 static void mpc52xx_psc_cw_disable_ints(struct uart_port *port) 223 { 224 out_be16(&PSC(port)->mpc52xx_psc_imr, 0); 225 } 226 227 static void mpc52xx_psc_cw_restore_ints(struct uart_port *port) 228 { 229 out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask); 230 } 231 232 static unsigned int mpc5200_psc_set_baudrate(struct uart_port *port, 233 struct ktermios *new, 234 struct ktermios *old) 235 { 236 unsigned int baud; 237 unsigned int divisor; 238 239 /* The 5200 has a fixed /32 prescaler, uartclk contains the ipb freq */ 240 baud = uart_get_baud_rate(port, new, old, 241 port->uartclk / (32 * 0xffff) + 1, 242 port->uartclk / 32); 243 divisor = (port->uartclk + 16 * baud) / (32 * baud); 244 245 /* enable the /32 prescaler and set the divisor */ 246 mpc52xx_set_divisor(PSC(port), 0xdd00, divisor); 247 return baud; 248 } 249 250 static unsigned int mpc5200b_psc_set_baudrate(struct uart_port *port, 251 struct ktermios *new, 252 struct ktermios *old) 253 { 254 unsigned int baud; 255 unsigned int divisor; 256 u16 prescaler; 257 258 /* The 5200B has a selectable /4 or /32 prescaler, uartclk contains the 259 * ipb freq */ 260 baud = uart_get_baud_rate(port, new, old, 261 port->uartclk / (32 * 0xffff) + 1, 262 port->uartclk / 4); 263 divisor = (port->uartclk + 2 * baud) / (4 * baud); 264 265 /* select the proper prescaler and set the divisor 266 * prefer high prescaler for more tolerance on low baudrates */ 267 if (divisor > 0xffff || baud <= 115200) { 268 divisor = (divisor + 4) / 8; 269 prescaler = 0xdd00; /* /32 */ 270 } else 271 prescaler = 0xff00; /* /4 */ 272 mpc52xx_set_divisor(PSC(port), prescaler, divisor); 273 return baud; 274 } 275 276 static void mpc52xx_psc_get_irq(struct uart_port *port, struct device_node *np) 277 { 278 port->irqflags = 0; 279 port->irq = irq_of_parse_and_map(np, 0); 280 } 281 282 /* 52xx specific interrupt handler. The caller holds the port lock */ 283 static irqreturn_t mpc52xx_psc_handle_irq(struct uart_port *port) 284 { 285 return mpc5xxx_uart_process_int(port); 286 } 287 288 static struct psc_ops mpc52xx_psc_ops = { 289 .fifo_init = mpc52xx_psc_fifo_init, 290 .raw_rx_rdy = mpc52xx_psc_raw_rx_rdy, 291 .raw_tx_rdy = mpc52xx_psc_raw_tx_rdy, 292 .rx_rdy = mpc52xx_psc_rx_rdy, 293 .tx_rdy = mpc52xx_psc_tx_rdy, 294 .tx_empty = mpc52xx_psc_tx_empty, 295 .stop_rx = mpc52xx_psc_stop_rx, 296 .start_tx = mpc52xx_psc_start_tx, 297 .stop_tx = mpc52xx_psc_stop_tx, 298 .rx_clr_irq = mpc52xx_psc_rx_clr_irq, 299 .tx_clr_irq = mpc52xx_psc_tx_clr_irq, 300 .write_char = mpc52xx_psc_write_char, 301 .read_char = mpc52xx_psc_read_char, 302 .cw_disable_ints = mpc52xx_psc_cw_disable_ints, 303 .cw_restore_ints = mpc52xx_psc_cw_restore_ints, 304 .set_baudrate = mpc5200_psc_set_baudrate, 305 .get_irq = mpc52xx_psc_get_irq, 306 .handle_irq = mpc52xx_psc_handle_irq, 307 }; 308 309 static struct psc_ops mpc5200b_psc_ops = { 310 .fifo_init = mpc52xx_psc_fifo_init, 311 .raw_rx_rdy = mpc52xx_psc_raw_rx_rdy, 312 .raw_tx_rdy = mpc52xx_psc_raw_tx_rdy, 313 .rx_rdy = mpc52xx_psc_rx_rdy, 314 .tx_rdy = mpc52xx_psc_tx_rdy, 315 .tx_empty = mpc52xx_psc_tx_empty, 316 .stop_rx = mpc52xx_psc_stop_rx, 317 .start_tx = mpc52xx_psc_start_tx, 318 .stop_tx = mpc52xx_psc_stop_tx, 319 .rx_clr_irq = mpc52xx_psc_rx_clr_irq, 320 .tx_clr_irq = mpc52xx_psc_tx_clr_irq, 321 .write_char = mpc52xx_psc_write_char, 322 .read_char = mpc52xx_psc_read_char, 323 .cw_disable_ints = mpc52xx_psc_cw_disable_ints, 324 .cw_restore_ints = mpc52xx_psc_cw_restore_ints, 325 .set_baudrate = mpc5200b_psc_set_baudrate, 326 .get_irq = mpc52xx_psc_get_irq, 327 .handle_irq = mpc52xx_psc_handle_irq, 328 }; 329 330 #endif /* CONFIG_MPC52xx */ 331 332 #ifdef CONFIG_PPC_MPC512x 333 #define FIFO_512x(port) ((struct mpc512x_psc_fifo __iomem *)(PSC(port)+1)) 334 335 /* PSC FIFO Controller for mpc512x */ 336 struct psc_fifoc { 337 u32 fifoc_cmd; 338 u32 fifoc_int; 339 u32 fifoc_dma; 340 u32 fifoc_axe; 341 u32 fifoc_debug; 342 }; 343 344 static struct psc_fifoc __iomem *psc_fifoc; 345 static unsigned int psc_fifoc_irq; 346 347 static void mpc512x_psc_fifo_init(struct uart_port *port) 348 { 349 /* /32 prescaler */ 350 out_be16(&PSC(port)->mpc52xx_psc_clock_select, 0xdd00); 351 352 out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE); 353 out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE); 354 out_be32(&FIFO_512x(port)->txalarm, 1); 355 out_be32(&FIFO_512x(port)->tximr, 0); 356 357 out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE); 358 out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE); 359 out_be32(&FIFO_512x(port)->rxalarm, 1); 360 out_be32(&FIFO_512x(port)->rximr, 0); 361 362 out_be32(&FIFO_512x(port)->tximr, MPC512x_PSC_FIFO_ALARM); 363 out_be32(&FIFO_512x(port)->rximr, MPC512x_PSC_FIFO_ALARM); 364 } 365 366 static int mpc512x_psc_raw_rx_rdy(struct uart_port *port) 367 { 368 return !(in_be32(&FIFO_512x(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY); 369 } 370 371 static int mpc512x_psc_raw_tx_rdy(struct uart_port *port) 372 { 373 return !(in_be32(&FIFO_512x(port)->txsr) & MPC512x_PSC_FIFO_FULL); 374 } 375 376 static int mpc512x_psc_rx_rdy(struct uart_port *port) 377 { 378 return in_be32(&FIFO_512x(port)->rxsr) 379 & in_be32(&FIFO_512x(port)->rximr) 380 & MPC512x_PSC_FIFO_ALARM; 381 } 382 383 static int mpc512x_psc_tx_rdy(struct uart_port *port) 384 { 385 return in_be32(&FIFO_512x(port)->txsr) 386 & in_be32(&FIFO_512x(port)->tximr) 387 & MPC512x_PSC_FIFO_ALARM; 388 } 389 390 static int mpc512x_psc_tx_empty(struct uart_port *port) 391 { 392 return in_be32(&FIFO_512x(port)->txsr) 393 & MPC512x_PSC_FIFO_EMPTY; 394 } 395 396 static void mpc512x_psc_stop_rx(struct uart_port *port) 397 { 398 unsigned long rx_fifo_imr; 399 400 rx_fifo_imr = in_be32(&FIFO_512x(port)->rximr); 401 rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM; 402 out_be32(&FIFO_512x(port)->rximr, rx_fifo_imr); 403 } 404 405 static void mpc512x_psc_start_tx(struct uart_port *port) 406 { 407 unsigned long tx_fifo_imr; 408 409 tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr); 410 tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM; 411 out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr); 412 } 413 414 static void mpc512x_psc_stop_tx(struct uart_port *port) 415 { 416 unsigned long tx_fifo_imr; 417 418 tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr); 419 tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM; 420 out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr); 421 } 422 423 static void mpc512x_psc_rx_clr_irq(struct uart_port *port) 424 { 425 out_be32(&FIFO_512x(port)->rxisr, in_be32(&FIFO_512x(port)->rxisr)); 426 } 427 428 static void mpc512x_psc_tx_clr_irq(struct uart_port *port) 429 { 430 out_be32(&FIFO_512x(port)->txisr, in_be32(&FIFO_512x(port)->txisr)); 431 } 432 433 static void mpc512x_psc_write_char(struct uart_port *port, unsigned char c) 434 { 435 out_8(&FIFO_512x(port)->txdata_8, c); 436 } 437 438 static unsigned char mpc512x_psc_read_char(struct uart_port *port) 439 { 440 return in_8(&FIFO_512x(port)->rxdata_8); 441 } 442 443 static void mpc512x_psc_cw_disable_ints(struct uart_port *port) 444 { 445 port->read_status_mask = 446 in_be32(&FIFO_512x(port)->tximr) << 16 | 447 in_be32(&FIFO_512x(port)->rximr); 448 out_be32(&FIFO_512x(port)->tximr, 0); 449 out_be32(&FIFO_512x(port)->rximr, 0); 450 } 451 452 static void mpc512x_psc_cw_restore_ints(struct uart_port *port) 453 { 454 out_be32(&FIFO_512x(port)->tximr, 455 (port->read_status_mask >> 16) & 0x7f); 456 out_be32(&FIFO_512x(port)->rximr, port->read_status_mask & 0x7f); 457 } 458 459 static unsigned int mpc512x_psc_set_baudrate(struct uart_port *port, 460 struct ktermios *new, 461 struct ktermios *old) 462 { 463 unsigned int baud; 464 unsigned int divisor; 465 466 /* 467 * The "MPC5121e Microcontroller Reference Manual, Rev. 3" says on 468 * pg. 30-10 that the chip supports a /32 and a /10 prescaler. 469 * Furthermore, it states that "After reset, the prescaler by 10 470 * for the UART mode is selected", but the reset register value is 471 * 0x0000 which means a /32 prescaler. This is wrong. 472 * 473 * In reality using /32 prescaler doesn't work, as it is not supported! 474 * Use /16 or /10 prescaler, see "MPC5121e Hardware Design Guide", 475 * Chapter 4.1 PSC in UART Mode. 476 * Calculate with a /16 prescaler here. 477 */ 478 479 /* uartclk contains the ips freq */ 480 baud = uart_get_baud_rate(port, new, old, 481 port->uartclk / (16 * 0xffff) + 1, 482 port->uartclk / 16); 483 divisor = (port->uartclk + 8 * baud) / (16 * baud); 484 485 /* enable the /16 prescaler and set the divisor */ 486 mpc52xx_set_divisor(PSC(port), 0xdd00, divisor); 487 return baud; 488 } 489 490 /* Init PSC FIFO Controller */ 491 static int __init mpc512x_psc_fifoc_init(void) 492 { 493 struct device_node *np; 494 495 np = of_find_compatible_node(NULL, NULL, 496 "fsl,mpc5121-psc-fifo"); 497 if (!np) { 498 pr_err("%s: Can't find FIFOC node\n", __func__); 499 return -ENODEV; 500 } 501 502 psc_fifoc = of_iomap(np, 0); 503 if (!psc_fifoc) { 504 pr_err("%s: Can't map FIFOC\n", __func__); 505 of_node_put(np); 506 return -ENODEV; 507 } 508 509 psc_fifoc_irq = irq_of_parse_and_map(np, 0); 510 of_node_put(np); 511 if (psc_fifoc_irq == 0) { 512 pr_err("%s: Can't get FIFOC irq\n", __func__); 513 iounmap(psc_fifoc); 514 return -ENODEV; 515 } 516 517 return 0; 518 } 519 520 static void __exit mpc512x_psc_fifoc_uninit(void) 521 { 522 iounmap(psc_fifoc); 523 } 524 525 /* 512x specific interrupt handler. The caller holds the port lock */ 526 static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port) 527 { 528 unsigned long fifoc_int; 529 int psc_num; 530 531 /* Read pending PSC FIFOC interrupts */ 532 fifoc_int = in_be32(&psc_fifoc->fifoc_int); 533 534 /* Check if it is an interrupt for this port */ 535 psc_num = (port->mapbase & 0xf00) >> 8; 536 if (test_bit(psc_num, &fifoc_int) || 537 test_bit(psc_num + 16, &fifoc_int)) 538 return mpc5xxx_uart_process_int(port); 539 540 return IRQ_NONE; 541 } 542 543 static int mpc512x_psc_clock(struct uart_port *port, int enable) 544 { 545 struct clk *psc_clk; 546 int psc_num; 547 char clk_name[10]; 548 549 if (uart_console(port)) 550 return 0; 551 552 psc_num = (port->mapbase & 0xf00) >> 8; 553 snprintf(clk_name, sizeof(clk_name), "psc%d_clk", psc_num); 554 psc_clk = clk_get(port->dev, clk_name); 555 if (IS_ERR(psc_clk)) { 556 dev_err(port->dev, "Failed to get PSC clock entry!\n"); 557 return -ENODEV; 558 } 559 560 dev_dbg(port->dev, "%s %sable\n", clk_name, enable ? "en" : "dis"); 561 562 if (enable) 563 clk_enable(psc_clk); 564 else 565 clk_disable(psc_clk); 566 567 return 0; 568 } 569 570 static void mpc512x_psc_get_irq(struct uart_port *port, struct device_node *np) 571 { 572 port->irqflags = IRQF_SHARED; 573 port->irq = psc_fifoc_irq; 574 } 575 576 static struct psc_ops mpc512x_psc_ops = { 577 .fifo_init = mpc512x_psc_fifo_init, 578 .raw_rx_rdy = mpc512x_psc_raw_rx_rdy, 579 .raw_tx_rdy = mpc512x_psc_raw_tx_rdy, 580 .rx_rdy = mpc512x_psc_rx_rdy, 581 .tx_rdy = mpc512x_psc_tx_rdy, 582 .tx_empty = mpc512x_psc_tx_empty, 583 .stop_rx = mpc512x_psc_stop_rx, 584 .start_tx = mpc512x_psc_start_tx, 585 .stop_tx = mpc512x_psc_stop_tx, 586 .rx_clr_irq = mpc512x_psc_rx_clr_irq, 587 .tx_clr_irq = mpc512x_psc_tx_clr_irq, 588 .write_char = mpc512x_psc_write_char, 589 .read_char = mpc512x_psc_read_char, 590 .cw_disable_ints = mpc512x_psc_cw_disable_ints, 591 .cw_restore_ints = mpc512x_psc_cw_restore_ints, 592 .set_baudrate = mpc512x_psc_set_baudrate, 593 .clock = mpc512x_psc_clock, 594 .fifoc_init = mpc512x_psc_fifoc_init, 595 .fifoc_uninit = mpc512x_psc_fifoc_uninit, 596 .get_irq = mpc512x_psc_get_irq, 597 .handle_irq = mpc512x_psc_handle_irq, 598 }; 599 #endif 600 601 static struct psc_ops *psc_ops; 602 603 /* ======================================================================== */ 604 /* UART operations */ 605 /* ======================================================================== */ 606 607 static unsigned int 608 mpc52xx_uart_tx_empty(struct uart_port *port) 609 { 610 return psc_ops->tx_empty(port) ? TIOCSER_TEMT : 0; 611 } 612 613 static void 614 mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) 615 { 616 if (mctrl & TIOCM_RTS) 617 out_8(&PSC(port)->op1, MPC52xx_PSC_OP_RTS); 618 else 619 out_8(&PSC(port)->op0, MPC52xx_PSC_OP_RTS); 620 } 621 622 static unsigned int 623 mpc52xx_uart_get_mctrl(struct uart_port *port) 624 { 625 unsigned int ret = TIOCM_DSR; 626 u8 status = in_8(&PSC(port)->mpc52xx_psc_ipcr); 627 628 if (!(status & MPC52xx_PSC_CTS)) 629 ret |= TIOCM_CTS; 630 if (!(status & MPC52xx_PSC_DCD)) 631 ret |= TIOCM_CAR; 632 633 return ret; 634 } 635 636 static void 637 mpc52xx_uart_stop_tx(struct uart_port *port) 638 { 639 /* port->lock taken by caller */ 640 psc_ops->stop_tx(port); 641 } 642 643 static void 644 mpc52xx_uart_start_tx(struct uart_port *port) 645 { 646 /* port->lock taken by caller */ 647 psc_ops->start_tx(port); 648 } 649 650 static void 651 mpc52xx_uart_send_xchar(struct uart_port *port, char ch) 652 { 653 unsigned long flags; 654 spin_lock_irqsave(&port->lock, flags); 655 656 port->x_char = ch; 657 if (ch) { 658 /* Make sure tx interrupts are on */ 659 /* Truly necessary ??? They should be anyway */ 660 psc_ops->start_tx(port); 661 } 662 663 spin_unlock_irqrestore(&port->lock, flags); 664 } 665 666 static void 667 mpc52xx_uart_stop_rx(struct uart_port *port) 668 { 669 /* port->lock taken by caller */ 670 psc_ops->stop_rx(port); 671 } 672 673 static void 674 mpc52xx_uart_enable_ms(struct uart_port *port) 675 { 676 struct mpc52xx_psc __iomem *psc = PSC(port); 677 678 /* clear D_*-bits by reading them */ 679 in_8(&psc->mpc52xx_psc_ipcr); 680 /* enable CTS and DCD as IPC interrupts */ 681 out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD); 682 683 port->read_status_mask |= MPC52xx_PSC_IMR_IPC; 684 out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask); 685 } 686 687 static void 688 mpc52xx_uart_break_ctl(struct uart_port *port, int ctl) 689 { 690 unsigned long flags; 691 spin_lock_irqsave(&port->lock, flags); 692 693 if (ctl == -1) 694 out_8(&PSC(port)->command, MPC52xx_PSC_START_BRK); 695 else 696 out_8(&PSC(port)->command, MPC52xx_PSC_STOP_BRK); 697 698 spin_unlock_irqrestore(&port->lock, flags); 699 } 700 701 static int 702 mpc52xx_uart_startup(struct uart_port *port) 703 { 704 struct mpc52xx_psc __iomem *psc = PSC(port); 705 int ret; 706 707 if (psc_ops->clock) { 708 ret = psc_ops->clock(port, 1); 709 if (ret) 710 return ret; 711 } 712 713 /* Request IRQ */ 714 ret = request_irq(port->irq, mpc52xx_uart_int, 715 port->irqflags, "mpc52xx_psc_uart", port); 716 if (ret) 717 return ret; 718 719 /* Reset/activate the port, clear and enable interrupts */ 720 out_8(&psc->command, MPC52xx_PSC_RST_RX); 721 out_8(&psc->command, MPC52xx_PSC_RST_TX); 722 723 out_be32(&psc->sicr, 0); /* UART mode DCD ignored */ 724 725 psc_ops->fifo_init(port); 726 727 out_8(&psc->command, MPC52xx_PSC_TX_ENABLE); 728 out_8(&psc->command, MPC52xx_PSC_RX_ENABLE); 729 730 return 0; 731 } 732 733 static void 734 mpc52xx_uart_shutdown(struct uart_port *port) 735 { 736 struct mpc52xx_psc __iomem *psc = PSC(port); 737 738 /* Shut down the port. Leave TX active if on a console port */ 739 out_8(&psc->command, MPC52xx_PSC_RST_RX); 740 if (!uart_console(port)) 741 out_8(&psc->command, MPC52xx_PSC_RST_TX); 742 743 port->read_status_mask = 0; 744 out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask); 745 746 if (psc_ops->clock) 747 psc_ops->clock(port, 0); 748 749 /* Release interrupt */ 750 free_irq(port->irq, port); 751 } 752 753 static void 754 mpc52xx_uart_set_termios(struct uart_port *port, struct ktermios *new, 755 struct ktermios *old) 756 { 757 struct mpc52xx_psc __iomem *psc = PSC(port); 758 unsigned long flags; 759 unsigned char mr1, mr2; 760 unsigned int j; 761 unsigned int baud; 762 763 /* Prepare what we're gonna write */ 764 mr1 = 0; 765 766 switch (new->c_cflag & CSIZE) { 767 case CS5: mr1 |= MPC52xx_PSC_MODE_5_BITS; 768 break; 769 case CS6: mr1 |= MPC52xx_PSC_MODE_6_BITS; 770 break; 771 case CS7: mr1 |= MPC52xx_PSC_MODE_7_BITS; 772 break; 773 case CS8: 774 default: mr1 |= MPC52xx_PSC_MODE_8_BITS; 775 } 776 777 if (new->c_cflag & PARENB) { 778 mr1 |= (new->c_cflag & PARODD) ? 779 MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN; 780 } else 781 mr1 |= MPC52xx_PSC_MODE_PARNONE; 782 783 784 mr2 = 0; 785 786 if (new->c_cflag & CSTOPB) 787 mr2 |= MPC52xx_PSC_MODE_TWO_STOP; 788 else 789 mr2 |= ((new->c_cflag & CSIZE) == CS5) ? 790 MPC52xx_PSC_MODE_ONE_STOP_5_BITS : 791 MPC52xx_PSC_MODE_ONE_STOP; 792 793 if (new->c_cflag & CRTSCTS) { 794 mr1 |= MPC52xx_PSC_MODE_RXRTS; 795 mr2 |= MPC52xx_PSC_MODE_TXCTS; 796 } 797 798 /* Get the lock */ 799 spin_lock_irqsave(&port->lock, flags); 800 801 /* Do our best to flush TX & RX, so we don't lose anything */ 802 /* But we don't wait indefinitely ! */ 803 j = 5000000; /* Maximum wait */ 804 /* FIXME Can't receive chars since set_termios might be called at early 805 * boot for the console, all stuff is not yet ready to receive at that 806 * time and that just makes the kernel oops */ 807 /* while (j-- && mpc52xx_uart_int_rx_chars(port)); */ 808 while (!mpc52xx_uart_tx_empty(port) && --j) 809 udelay(1); 810 811 if (!j) 812 printk(KERN_ERR "mpc52xx_uart.c: " 813 "Unable to flush RX & TX fifos in-time in set_termios." 814 "Some chars may have been lost.\n"); 815 816 /* Reset the TX & RX */ 817 out_8(&psc->command, MPC52xx_PSC_RST_RX); 818 out_8(&psc->command, MPC52xx_PSC_RST_TX); 819 820 /* Send new mode settings */ 821 out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1); 822 out_8(&psc->mode, mr1); 823 out_8(&psc->mode, mr2); 824 baud = psc_ops->set_baudrate(port, new, old); 825 826 /* Update the per-port timeout */ 827 uart_update_timeout(port, new->c_cflag, baud); 828 829 if (UART_ENABLE_MS(port, new->c_cflag)) 830 mpc52xx_uart_enable_ms(port); 831 832 /* Reenable TX & RX */ 833 out_8(&psc->command, MPC52xx_PSC_TX_ENABLE); 834 out_8(&psc->command, MPC52xx_PSC_RX_ENABLE); 835 836 /* We're all set, release the lock */ 837 spin_unlock_irqrestore(&port->lock, flags); 838 } 839 840 static const char * 841 mpc52xx_uart_type(struct uart_port *port) 842 { 843 /* 844 * We keep using PORT_MPC52xx for historic reasons although it applies 845 * for MPC512x, too, but print "MPC5xxx" to not irritate users 846 */ 847 return port->type == PORT_MPC52xx ? "MPC5xxx PSC" : NULL; 848 } 849 850 static void 851 mpc52xx_uart_release_port(struct uart_port *port) 852 { 853 /* remapped by us ? */ 854 if (port->flags & UPF_IOREMAP) { 855 iounmap(port->membase); 856 port->membase = NULL; 857 } 858 859 release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc)); 860 } 861 862 static int 863 mpc52xx_uart_request_port(struct uart_port *port) 864 { 865 int err; 866 867 if (port->flags & UPF_IOREMAP) /* Need to remap ? */ 868 port->membase = ioremap(port->mapbase, 869 sizeof(struct mpc52xx_psc)); 870 871 if (!port->membase) 872 return -EINVAL; 873 874 err = request_mem_region(port->mapbase, sizeof(struct mpc52xx_psc), 875 "mpc52xx_psc_uart") != NULL ? 0 : -EBUSY; 876 877 if (err && (port->flags & UPF_IOREMAP)) { 878 iounmap(port->membase); 879 port->membase = NULL; 880 } 881 882 return err; 883 } 884 885 static void 886 mpc52xx_uart_config_port(struct uart_port *port, int flags) 887 { 888 if ((flags & UART_CONFIG_TYPE) 889 && (mpc52xx_uart_request_port(port) == 0)) 890 port->type = PORT_MPC52xx; 891 } 892 893 static int 894 mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser) 895 { 896 if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx) 897 return -EINVAL; 898 899 if ((ser->irq != port->irq) || 900 (ser->io_type != UPIO_MEM) || 901 (ser->baud_base != port->uartclk) || 902 (ser->iomem_base != (void *)port->mapbase) || 903 (ser->hub6 != 0)) 904 return -EINVAL; 905 906 return 0; 907 } 908 909 910 static struct uart_ops mpc52xx_uart_ops = { 911 .tx_empty = mpc52xx_uart_tx_empty, 912 .set_mctrl = mpc52xx_uart_set_mctrl, 913 .get_mctrl = mpc52xx_uart_get_mctrl, 914 .stop_tx = mpc52xx_uart_stop_tx, 915 .start_tx = mpc52xx_uart_start_tx, 916 .send_xchar = mpc52xx_uart_send_xchar, 917 .stop_rx = mpc52xx_uart_stop_rx, 918 .enable_ms = mpc52xx_uart_enable_ms, 919 .break_ctl = mpc52xx_uart_break_ctl, 920 .startup = mpc52xx_uart_startup, 921 .shutdown = mpc52xx_uart_shutdown, 922 .set_termios = mpc52xx_uart_set_termios, 923 /* .pm = mpc52xx_uart_pm, Not supported yet */ 924 /* .set_wake = mpc52xx_uart_set_wake, Not supported yet */ 925 .type = mpc52xx_uart_type, 926 .release_port = mpc52xx_uart_release_port, 927 .request_port = mpc52xx_uart_request_port, 928 .config_port = mpc52xx_uart_config_port, 929 .verify_port = mpc52xx_uart_verify_port 930 }; 931 932 933 /* ======================================================================== */ 934 /* Interrupt handling */ 935 /* ======================================================================== */ 936 937 static inline int 938 mpc52xx_uart_int_rx_chars(struct uart_port *port) 939 { 940 struct tty_struct *tty = port->state->port.tty; 941 unsigned char ch, flag; 942 unsigned short status; 943 944 /* While we can read, do so ! */ 945 while (psc_ops->raw_rx_rdy(port)) { 946 /* Get the char */ 947 ch = psc_ops->read_char(port); 948 949 /* Handle sysreq char */ 950 #ifdef SUPPORT_SYSRQ 951 if (uart_handle_sysrq_char(port, ch)) { 952 port->sysrq = 0; 953 continue; 954 } 955 #endif 956 957 /* Store it */ 958 959 flag = TTY_NORMAL; 960 port->icount.rx++; 961 962 status = in_be16(&PSC(port)->mpc52xx_psc_status); 963 964 if (status & (MPC52xx_PSC_SR_PE | 965 MPC52xx_PSC_SR_FE | 966 MPC52xx_PSC_SR_RB)) { 967 968 if (status & MPC52xx_PSC_SR_RB) { 969 flag = TTY_BREAK; 970 uart_handle_break(port); 971 port->icount.brk++; 972 } else if (status & MPC52xx_PSC_SR_PE) { 973 flag = TTY_PARITY; 974 port->icount.parity++; 975 } 976 else if (status & MPC52xx_PSC_SR_FE) { 977 flag = TTY_FRAME; 978 port->icount.frame++; 979 } 980 981 /* Clear error condition */ 982 out_8(&PSC(port)->command, MPC52xx_PSC_RST_ERR_STAT); 983 984 } 985 tty_insert_flip_char(tty, ch, flag); 986 if (status & MPC52xx_PSC_SR_OE) { 987 /* 988 * Overrun is special, since it's 989 * reported immediately, and doesn't 990 * affect the current character 991 */ 992 tty_insert_flip_char(tty, 0, TTY_OVERRUN); 993 port->icount.overrun++; 994 } 995 } 996 997 spin_unlock(&port->lock); 998 tty_flip_buffer_push(tty); 999 spin_lock(&port->lock); 1000 1001 return psc_ops->raw_rx_rdy(port); 1002 } 1003 1004 static inline int 1005 mpc52xx_uart_int_tx_chars(struct uart_port *port) 1006 { 1007 struct circ_buf *xmit = &port->state->xmit; 1008 1009 /* Process out of band chars */ 1010 if (port->x_char) { 1011 psc_ops->write_char(port, port->x_char); 1012 port->icount.tx++; 1013 port->x_char = 0; 1014 return 1; 1015 } 1016 1017 /* Nothing to do ? */ 1018 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { 1019 mpc52xx_uart_stop_tx(port); 1020 return 0; 1021 } 1022 1023 /* Send chars */ 1024 while (psc_ops->raw_tx_rdy(port)) { 1025 psc_ops->write_char(port, xmit->buf[xmit->tail]); 1026 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); 1027 port->icount.tx++; 1028 if (uart_circ_empty(xmit)) 1029 break; 1030 } 1031 1032 /* Wake up */ 1033 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) 1034 uart_write_wakeup(port); 1035 1036 /* Maybe we're done after all */ 1037 if (uart_circ_empty(xmit)) { 1038 mpc52xx_uart_stop_tx(port); 1039 return 0; 1040 } 1041 1042 return 1; 1043 } 1044 1045 static irqreturn_t 1046 mpc5xxx_uart_process_int(struct uart_port *port) 1047 { 1048 unsigned long pass = ISR_PASS_LIMIT; 1049 unsigned int keepgoing; 1050 u8 status; 1051 1052 /* While we have stuff to do, we continue */ 1053 do { 1054 /* If we don't find anything to do, we stop */ 1055 keepgoing = 0; 1056 1057 psc_ops->rx_clr_irq(port); 1058 if (psc_ops->rx_rdy(port)) 1059 keepgoing |= mpc52xx_uart_int_rx_chars(port); 1060 1061 psc_ops->tx_clr_irq(port); 1062 if (psc_ops->tx_rdy(port)) 1063 keepgoing |= mpc52xx_uart_int_tx_chars(port); 1064 1065 status = in_8(&PSC(port)->mpc52xx_psc_ipcr); 1066 if (status & MPC52xx_PSC_D_DCD) 1067 uart_handle_dcd_change(port, !(status & MPC52xx_PSC_DCD)); 1068 1069 if (status & MPC52xx_PSC_D_CTS) 1070 uart_handle_cts_change(port, !(status & MPC52xx_PSC_CTS)); 1071 1072 /* Limit number of iteration */ 1073 if (!(--pass)) 1074 keepgoing = 0; 1075 1076 } while (keepgoing); 1077 1078 return IRQ_HANDLED; 1079 } 1080 1081 static irqreturn_t 1082 mpc52xx_uart_int(int irq, void *dev_id) 1083 { 1084 struct uart_port *port = dev_id; 1085 irqreturn_t ret; 1086 1087 spin_lock(&port->lock); 1088 1089 ret = psc_ops->handle_irq(port); 1090 1091 spin_unlock(&port->lock); 1092 1093 return ret; 1094 } 1095 1096 /* ======================================================================== */ 1097 /* Console ( if applicable ) */ 1098 /* ======================================================================== */ 1099 1100 #ifdef CONFIG_SERIAL_MPC52xx_CONSOLE 1101 1102 static void __init 1103 mpc52xx_console_get_options(struct uart_port *port, 1104 int *baud, int *parity, int *bits, int *flow) 1105 { 1106 struct mpc52xx_psc __iomem *psc = PSC(port); 1107 unsigned char mr1; 1108 1109 pr_debug("mpc52xx_console_get_options(port=%p)\n", port); 1110 1111 /* Read the mode registers */ 1112 out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1); 1113 mr1 = in_8(&psc->mode); 1114 1115 /* CT{U,L}R are write-only ! */ 1116 *baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD; 1117 1118 /* Parse them */ 1119 switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) { 1120 case MPC52xx_PSC_MODE_5_BITS: 1121 *bits = 5; 1122 break; 1123 case MPC52xx_PSC_MODE_6_BITS: 1124 *bits = 6; 1125 break; 1126 case MPC52xx_PSC_MODE_7_BITS: 1127 *bits = 7; 1128 break; 1129 case MPC52xx_PSC_MODE_8_BITS: 1130 default: 1131 *bits = 8; 1132 } 1133 1134 if (mr1 & MPC52xx_PSC_MODE_PARNONE) 1135 *parity = 'n'; 1136 else 1137 *parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e'; 1138 } 1139 1140 static void 1141 mpc52xx_console_write(struct console *co, const char *s, unsigned int count) 1142 { 1143 struct uart_port *port = &mpc52xx_uart_ports[co->index]; 1144 unsigned int i, j; 1145 1146 /* Disable interrupts */ 1147 psc_ops->cw_disable_ints(port); 1148 1149 /* Wait the TX buffer to be empty */ 1150 j = 5000000; /* Maximum wait */ 1151 while (!mpc52xx_uart_tx_empty(port) && --j) 1152 udelay(1); 1153 1154 /* Write all the chars */ 1155 for (i = 0; i < count; i++, s++) { 1156 /* Line return handling */ 1157 if (*s == '\n') 1158 psc_ops->write_char(port, '\r'); 1159 1160 /* Send the char */ 1161 psc_ops->write_char(port, *s); 1162 1163 /* Wait the TX buffer to be empty */ 1164 j = 20000; /* Maximum wait */ 1165 while (!mpc52xx_uart_tx_empty(port) && --j) 1166 udelay(1); 1167 } 1168 1169 /* Restore interrupt state */ 1170 psc_ops->cw_restore_ints(port); 1171 } 1172 1173 1174 static int __init 1175 mpc52xx_console_setup(struct console *co, char *options) 1176 { 1177 struct uart_port *port = &mpc52xx_uart_ports[co->index]; 1178 struct device_node *np = mpc52xx_uart_nodes[co->index]; 1179 unsigned int uartclk; 1180 struct resource res; 1181 int ret; 1182 1183 int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD; 1184 int bits = 8; 1185 int parity = 'n'; 1186 int flow = 'n'; 1187 1188 pr_debug("mpc52xx_console_setup co=%p, co->index=%i, options=%s\n", 1189 co, co->index, options); 1190 1191 if ((co->index < 0) || (co->index >= MPC52xx_PSC_MAXNUM)) { 1192 pr_debug("PSC%x out of range\n", co->index); 1193 return -EINVAL; 1194 } 1195 1196 if (!np) { 1197 pr_debug("PSC%x not found in device tree\n", co->index); 1198 return -EINVAL; 1199 } 1200 1201 pr_debug("Console on ttyPSC%x is %s\n", 1202 co->index, mpc52xx_uart_nodes[co->index]->full_name); 1203 1204 /* Fetch register locations */ 1205 ret = of_address_to_resource(np, 0, &res); 1206 if (ret) { 1207 pr_debug("Could not get resources for PSC%x\n", co->index); 1208 return ret; 1209 } 1210 1211 uartclk = mpc5xxx_get_bus_frequency(np); 1212 if (uartclk == 0) { 1213 pr_debug("Could not find uart clock frequency!\n"); 1214 return -EINVAL; 1215 } 1216 1217 /* Basic port init. Needed since we use some uart_??? func before 1218 * real init for early access */ 1219 spin_lock_init(&port->lock); 1220 port->uartclk = uartclk; 1221 port->ops = &mpc52xx_uart_ops; 1222 port->mapbase = res.start; 1223 port->membase = ioremap(res.start, sizeof(struct mpc52xx_psc)); 1224 port->irq = irq_of_parse_and_map(np, 0); 1225 1226 if (port->membase == NULL) 1227 return -EINVAL; 1228 1229 pr_debug("mpc52xx-psc uart at %p, mapped to %p, irq=%x, freq=%i\n", 1230 (void *)port->mapbase, port->membase, 1231 port->irq, port->uartclk); 1232 1233 /* Setup the port parameters accoding to options */ 1234 if (options) 1235 uart_parse_options(options, &baud, &parity, &bits, &flow); 1236 else 1237 mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow); 1238 1239 pr_debug("Setting console parameters: %i %i%c1 flow=%c\n", 1240 baud, bits, parity, flow); 1241 1242 return uart_set_options(port, co, baud, parity, bits, flow); 1243 } 1244 1245 1246 static struct uart_driver mpc52xx_uart_driver; 1247 1248 static struct console mpc52xx_console = { 1249 .name = "ttyPSC", 1250 .write = mpc52xx_console_write, 1251 .device = uart_console_device, 1252 .setup = mpc52xx_console_setup, 1253 .flags = CON_PRINTBUFFER, 1254 .index = -1, /* Specified on the cmdline (e.g. console=ttyPSC0) */ 1255 .data = &mpc52xx_uart_driver, 1256 }; 1257 1258 1259 static int __init 1260 mpc52xx_console_init(void) 1261 { 1262 mpc52xx_uart_of_enumerate(); 1263 register_console(&mpc52xx_console); 1264 return 0; 1265 } 1266 1267 console_initcall(mpc52xx_console_init); 1268 1269 #define MPC52xx_PSC_CONSOLE &mpc52xx_console 1270 #else 1271 #define MPC52xx_PSC_CONSOLE NULL 1272 #endif 1273 1274 1275 /* ======================================================================== */ 1276 /* UART Driver */ 1277 /* ======================================================================== */ 1278 1279 static struct uart_driver mpc52xx_uart_driver = { 1280 .driver_name = "mpc52xx_psc_uart", 1281 .dev_name = "ttyPSC", 1282 .major = SERIAL_PSC_MAJOR, 1283 .minor = SERIAL_PSC_MINOR, 1284 .nr = MPC52xx_PSC_MAXNUM, 1285 .cons = MPC52xx_PSC_CONSOLE, 1286 }; 1287 1288 /* ======================================================================== */ 1289 /* OF Platform Driver */ 1290 /* ======================================================================== */ 1291 1292 static struct of_device_id mpc52xx_uart_of_match[] = { 1293 #ifdef CONFIG_PPC_MPC52xx 1294 { .compatible = "fsl,mpc5200b-psc-uart", .data = &mpc5200b_psc_ops, }, 1295 { .compatible = "fsl,mpc5200-psc-uart", .data = &mpc52xx_psc_ops, }, 1296 /* binding used by old lite5200 device trees: */ 1297 { .compatible = "mpc5200-psc-uart", .data = &mpc52xx_psc_ops, }, 1298 /* binding used by efika: */ 1299 { .compatible = "mpc5200-serial", .data = &mpc52xx_psc_ops, }, 1300 #endif 1301 #ifdef CONFIG_PPC_MPC512x 1302 { .compatible = "fsl,mpc5121-psc-uart", .data = &mpc512x_psc_ops, }, 1303 #endif 1304 {}, 1305 }; 1306 1307 static int __devinit mpc52xx_uart_of_probe(struct platform_device *op) 1308 { 1309 int idx = -1; 1310 unsigned int uartclk; 1311 struct uart_port *port = NULL; 1312 struct resource res; 1313 int ret; 1314 1315 /* Check validity & presence */ 1316 for (idx = 0; idx < MPC52xx_PSC_MAXNUM; idx++) 1317 if (mpc52xx_uart_nodes[idx] == op->dev.of_node) 1318 break; 1319 if (idx >= MPC52xx_PSC_MAXNUM) 1320 return -EINVAL; 1321 pr_debug("Found %s assigned to ttyPSC%x\n", 1322 mpc52xx_uart_nodes[idx]->full_name, idx); 1323 1324 /* set the uart clock to the input clock of the psc, the different 1325 * prescalers are taken into account in the set_baudrate() methods 1326 * of the respective chip */ 1327 uartclk = mpc5xxx_get_bus_frequency(op->dev.of_node); 1328 if (uartclk == 0) { 1329 dev_dbg(&op->dev, "Could not find uart clock frequency!\n"); 1330 return -EINVAL; 1331 } 1332 1333 /* Init the port structure */ 1334 port = &mpc52xx_uart_ports[idx]; 1335 1336 spin_lock_init(&port->lock); 1337 port->uartclk = uartclk; 1338 port->fifosize = 512; 1339 port->iotype = UPIO_MEM; 1340 port->flags = UPF_BOOT_AUTOCONF | 1341 (uart_console(port) ? 0 : UPF_IOREMAP); 1342 port->line = idx; 1343 port->ops = &mpc52xx_uart_ops; 1344 port->dev = &op->dev; 1345 1346 /* Search for IRQ and mapbase */ 1347 ret = of_address_to_resource(op->dev.of_node, 0, &res); 1348 if (ret) 1349 return ret; 1350 1351 port->mapbase = res.start; 1352 if (!port->mapbase) { 1353 dev_dbg(&op->dev, "Could not allocate resources for PSC\n"); 1354 return -EINVAL; 1355 } 1356 1357 psc_ops->get_irq(port, op->dev.of_node); 1358 if (port->irq == 0) { 1359 dev_dbg(&op->dev, "Could not get irq\n"); 1360 return -EINVAL; 1361 } 1362 1363 dev_dbg(&op->dev, "mpc52xx-psc uart at %p, irq=%x, freq=%i\n", 1364 (void *)port->mapbase, port->irq, port->uartclk); 1365 1366 /* Add the port to the uart sub-system */ 1367 ret = uart_add_one_port(&mpc52xx_uart_driver, port); 1368 if (ret) 1369 return ret; 1370 1371 dev_set_drvdata(&op->dev, (void *)port); 1372 return 0; 1373 } 1374 1375 static int 1376 mpc52xx_uart_of_remove(struct platform_device *op) 1377 { 1378 struct uart_port *port = dev_get_drvdata(&op->dev); 1379 dev_set_drvdata(&op->dev, NULL); 1380 1381 if (port) 1382 uart_remove_one_port(&mpc52xx_uart_driver, port); 1383 1384 return 0; 1385 } 1386 1387 #ifdef CONFIG_PM 1388 static int 1389 mpc52xx_uart_of_suspend(struct platform_device *op, pm_message_t state) 1390 { 1391 struct uart_port *port = (struct uart_port *) dev_get_drvdata(&op->dev); 1392 1393 if (port) 1394 uart_suspend_port(&mpc52xx_uart_driver, port); 1395 1396 return 0; 1397 } 1398 1399 static int 1400 mpc52xx_uart_of_resume(struct platform_device *op) 1401 { 1402 struct uart_port *port = (struct uart_port *) dev_get_drvdata(&op->dev); 1403 1404 if (port) 1405 uart_resume_port(&mpc52xx_uart_driver, port); 1406 1407 return 0; 1408 } 1409 #endif 1410 1411 static void 1412 mpc52xx_uart_of_assign(struct device_node *np) 1413 { 1414 int i; 1415 1416 /* Find the first free PSC number */ 1417 for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) { 1418 if (mpc52xx_uart_nodes[i] == NULL) { 1419 of_node_get(np); 1420 mpc52xx_uart_nodes[i] = np; 1421 return; 1422 } 1423 } 1424 } 1425 1426 static void 1427 mpc52xx_uart_of_enumerate(void) 1428 { 1429 static int enum_done; 1430 struct device_node *np; 1431 const struct of_device_id *match; 1432 int i; 1433 1434 if (enum_done) 1435 return; 1436 1437 /* Assign index to each PSC in device tree */ 1438 for_each_matching_node(np, mpc52xx_uart_of_match) { 1439 match = of_match_node(mpc52xx_uart_of_match, np); 1440 psc_ops = match->data; 1441 mpc52xx_uart_of_assign(np); 1442 } 1443 1444 enum_done = 1; 1445 1446 for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) { 1447 if (mpc52xx_uart_nodes[i]) 1448 pr_debug("%s assigned to ttyPSC%x\n", 1449 mpc52xx_uart_nodes[i]->full_name, i); 1450 } 1451 } 1452 1453 MODULE_DEVICE_TABLE(of, mpc52xx_uart_of_match); 1454 1455 static struct platform_driver mpc52xx_uart_of_driver = { 1456 .probe = mpc52xx_uart_of_probe, 1457 .remove = mpc52xx_uart_of_remove, 1458 #ifdef CONFIG_PM 1459 .suspend = mpc52xx_uart_of_suspend, 1460 .resume = mpc52xx_uart_of_resume, 1461 #endif 1462 .driver = { 1463 .name = "mpc52xx-psc-uart", 1464 .owner = THIS_MODULE, 1465 .of_match_table = mpc52xx_uart_of_match, 1466 }, 1467 }; 1468 1469 1470 /* ======================================================================== */ 1471 /* Module */ 1472 /* ======================================================================== */ 1473 1474 static int __init 1475 mpc52xx_uart_init(void) 1476 { 1477 int ret; 1478 1479 printk(KERN_INFO "Serial: MPC52xx PSC UART driver\n"); 1480 1481 ret = uart_register_driver(&mpc52xx_uart_driver); 1482 if (ret) { 1483 printk(KERN_ERR "%s: uart_register_driver failed (%i)\n", 1484 __FILE__, ret); 1485 return ret; 1486 } 1487 1488 mpc52xx_uart_of_enumerate(); 1489 1490 /* 1491 * Map the PSC FIFO Controller and init if on MPC512x. 1492 */ 1493 if (psc_ops && psc_ops->fifoc_init) { 1494 ret = psc_ops->fifoc_init(); 1495 if (ret) 1496 return ret; 1497 } 1498 1499 ret = platform_driver_register(&mpc52xx_uart_of_driver); 1500 if (ret) { 1501 printk(KERN_ERR "%s: platform_driver_register failed (%i)\n", 1502 __FILE__, ret); 1503 uart_unregister_driver(&mpc52xx_uart_driver); 1504 return ret; 1505 } 1506 1507 return 0; 1508 } 1509 1510 static void __exit 1511 mpc52xx_uart_exit(void) 1512 { 1513 if (psc_ops->fifoc_uninit) 1514 psc_ops->fifoc_uninit(); 1515 1516 platform_driver_unregister(&mpc52xx_uart_of_driver); 1517 uart_unregister_driver(&mpc52xx_uart_driver); 1518 } 1519 1520 1521 module_init(mpc52xx_uart_init); 1522 module_exit(mpc52xx_uart_exit); 1523 1524 MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>"); 1525 MODULE_DESCRIPTION("Freescale MPC52xx PSC UART"); 1526 MODULE_LICENSE("GPL"); 1527