1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Freescale QUICC Engine UART device driver 4 * 5 * Author: Timur Tabi <timur@freescale.com> 6 * 7 * Copyright 2007 Freescale Semiconductor, Inc. 8 * 9 * This driver adds support for UART devices via Freescale's QUICC Engine 10 * found on some Freescale SOCs. 11 * 12 * If Soft-UART support is needed but not already present, then this driver 13 * will request and upload the "Soft-UART" microcode upon probe. The 14 * filename of the microcode should be fsl_qe_ucode_uart_X_YZ.bin, where "X" 15 * is the name of the SOC (e.g. 8323), and YZ is the revision of the SOC, 16 * (e.g. "11" for 1.1). 17 */ 18 19 #include <linux/module.h> 20 #include <linux/serial.h> 21 #include <linux/serial_core.h> 22 #include <linux/slab.h> 23 #include <linux/tty.h> 24 #include <linux/tty_flip.h> 25 #include <linux/io.h> 26 #include <linux/of_address.h> 27 #include <linux/of_irq.h> 28 #include <linux/of_platform.h> 29 #include <linux/dma-mapping.h> 30 31 #include <linux/fs_uart_pd.h> 32 #include <soc/fsl/qe/ucc_slow.h> 33 34 #include <linux/firmware.h> 35 #include <soc/fsl/cpm.h> 36 37 #ifdef CONFIG_PPC32 38 #include <asm/reg.h> /* mfspr, SPRN_SVR */ 39 #endif 40 41 /* 42 * The GUMR flag for Soft UART. This would normally be defined in qe.h, 43 * but Soft-UART is a hack and we want to keep everything related to it in 44 * this file. 45 */ 46 #define UCC_SLOW_GUMR_H_SUART 0x00004000 /* Soft-UART */ 47 48 /* 49 * soft_uart is 1 if we need to use Soft-UART mode 50 */ 51 static int soft_uart; 52 /* 53 * firmware_loaded is 1 if the firmware has been loaded, 0 otherwise. 54 */ 55 static int firmware_loaded; 56 57 /* Enable this macro to configure all serial ports in internal loopback 58 mode */ 59 /* #define LOOPBACK */ 60 61 /* The major and minor device numbers are defined in 62 * http://www.lanana.org/docs/device-list/devices-2.6+.txt. For the QE 63 * UART, we have major number 204 and minor numbers 46 - 49, which are the 64 * same as for the CPM2. This decision was made because no Freescale part 65 * has both a CPM and a QE. 66 */ 67 #define SERIAL_QE_MAJOR 204 68 #define SERIAL_QE_MINOR 46 69 70 /* Since we only have minor numbers 46 - 49, there is a hard limit of 4 ports */ 71 #define UCC_MAX_UART 4 72 73 /* The number of buffer descriptors for receiving characters. */ 74 #define RX_NUM_FIFO 4 75 76 /* The number of buffer descriptors for transmitting characters. */ 77 #define TX_NUM_FIFO 4 78 79 /* The maximum size of the character buffer for a single RX BD. */ 80 #define RX_BUF_SIZE 32 81 82 /* The maximum size of the character buffer for a single TX BD. */ 83 #define TX_BUF_SIZE 32 84 85 /* 86 * The number of jiffies to wait after receiving a close command before the 87 * device is actually closed. This allows the last few characters to be 88 * sent over the wire. 89 */ 90 #define UCC_WAIT_CLOSING 100 91 92 struct ucc_uart_pram { 93 struct ucc_slow_pram common; 94 u8 res1[8]; /* reserved */ 95 __be16 maxidl; /* Maximum idle chars */ 96 __be16 idlc; /* temp idle counter */ 97 __be16 brkcr; /* Break count register */ 98 __be16 parec; /* receive parity error counter */ 99 __be16 frmec; /* receive framing error counter */ 100 __be16 nosec; /* receive noise counter */ 101 __be16 brkec; /* receive break condition counter */ 102 __be16 brkln; /* last received break length */ 103 __be16 uaddr[2]; /* UART address character 1 & 2 */ 104 __be16 rtemp; /* Temp storage */ 105 __be16 toseq; /* Transmit out of sequence char */ 106 __be16 cchars[8]; /* control characters 1-8 */ 107 __be16 rccm; /* receive control character mask */ 108 __be16 rccr; /* receive control character register */ 109 __be16 rlbc; /* receive last break character */ 110 __be16 res2; /* reserved */ 111 __be32 res3; /* reserved, should be cleared */ 112 u8 res4; /* reserved, should be cleared */ 113 u8 res5[3]; /* reserved, should be cleared */ 114 __be32 res6; /* reserved, should be cleared */ 115 __be32 res7; /* reserved, should be cleared */ 116 __be32 res8; /* reserved, should be cleared */ 117 __be32 res9; /* reserved, should be cleared */ 118 __be32 res10; /* reserved, should be cleared */ 119 __be32 res11; /* reserved, should be cleared */ 120 __be32 res12; /* reserved, should be cleared */ 121 __be32 res13; /* reserved, should be cleared */ 122 /* The rest is for Soft-UART only */ 123 __be16 supsmr; /* 0x90, Shadow UPSMR */ 124 __be16 res92; /* 0x92, reserved, initialize to 0 */ 125 __be32 rx_state; /* 0x94, RX state, initialize to 0 */ 126 __be32 rx_cnt; /* 0x98, RX count, initialize to 0 */ 127 u8 rx_length; /* 0x9C, Char length, set to 1+CL+PEN+1+SL */ 128 u8 rx_bitmark; /* 0x9D, reserved, initialize to 0 */ 129 u8 rx_temp_dlst_qe; /* 0x9E, reserved, initialize to 0 */ 130 u8 res14[0xBC - 0x9F]; /* reserved */ 131 __be32 dump_ptr; /* 0xBC, Dump pointer */ 132 __be32 rx_frame_rem; /* 0xC0, reserved, initialize to 0 */ 133 u8 rx_frame_rem_size; /* 0xC4, reserved, initialize to 0 */ 134 u8 tx_mode; /* 0xC5, mode, 0=AHDLC, 1=UART */ 135 __be16 tx_state; /* 0xC6, TX state */ 136 u8 res15[0xD0 - 0xC8]; /* reserved */ 137 __be32 resD0; /* 0xD0, reserved, initialize to 0 */ 138 u8 resD4; /* 0xD4, reserved, initialize to 0 */ 139 __be16 resD5; /* 0xD5, reserved, initialize to 0 */ 140 } __attribute__ ((packed)); 141 142 /* SUPSMR definitions, for Soft-UART only */ 143 #define UCC_UART_SUPSMR_SL 0x8000 144 #define UCC_UART_SUPSMR_RPM_MASK 0x6000 145 #define UCC_UART_SUPSMR_RPM_ODD 0x0000 146 #define UCC_UART_SUPSMR_RPM_LOW 0x2000 147 #define UCC_UART_SUPSMR_RPM_EVEN 0x4000 148 #define UCC_UART_SUPSMR_RPM_HIGH 0x6000 149 #define UCC_UART_SUPSMR_PEN 0x1000 150 #define UCC_UART_SUPSMR_TPM_MASK 0x0C00 151 #define UCC_UART_SUPSMR_TPM_ODD 0x0000 152 #define UCC_UART_SUPSMR_TPM_LOW 0x0400 153 #define UCC_UART_SUPSMR_TPM_EVEN 0x0800 154 #define UCC_UART_SUPSMR_TPM_HIGH 0x0C00 155 #define UCC_UART_SUPSMR_FRZ 0x0100 156 #define UCC_UART_SUPSMR_UM_MASK 0x00c0 157 #define UCC_UART_SUPSMR_UM_NORMAL 0x0000 158 #define UCC_UART_SUPSMR_UM_MAN_MULTI 0x0040 159 #define UCC_UART_SUPSMR_UM_AUTO_MULTI 0x00c0 160 #define UCC_UART_SUPSMR_CL_MASK 0x0030 161 #define UCC_UART_SUPSMR_CL_8 0x0030 162 #define UCC_UART_SUPSMR_CL_7 0x0020 163 #define UCC_UART_SUPSMR_CL_6 0x0010 164 #define UCC_UART_SUPSMR_CL_5 0x0000 165 166 #define UCC_UART_TX_STATE_AHDLC 0x00 167 #define UCC_UART_TX_STATE_UART 0x01 168 #define UCC_UART_TX_STATE_X1 0x00 169 #define UCC_UART_TX_STATE_X16 0x80 170 171 #define UCC_UART_PRAM_ALIGNMENT 0x100 172 173 #define UCC_UART_SIZE_OF_BD UCC_SLOW_SIZE_OF_BD 174 #define NUM_CONTROL_CHARS 8 175 176 /* Private per-port data structure */ 177 struct uart_qe_port { 178 struct uart_port port; 179 struct ucc_slow __iomem *uccp; 180 struct ucc_uart_pram __iomem *uccup; 181 struct ucc_slow_info us_info; 182 struct ucc_slow_private *us_private; 183 struct device_node *np; 184 unsigned int ucc_num; /* First ucc is 0, not 1 */ 185 186 u16 rx_nrfifos; 187 u16 rx_fifosize; 188 u16 tx_nrfifos; 189 u16 tx_fifosize; 190 int wait_closing; 191 u32 flags; 192 struct qe_bd *rx_bd_base; 193 struct qe_bd *rx_cur; 194 struct qe_bd *tx_bd_base; 195 struct qe_bd *tx_cur; 196 unsigned char *tx_buf; 197 unsigned char *rx_buf; 198 void *bd_virt; /* virtual address of the BD buffers */ 199 dma_addr_t bd_dma_addr; /* bus address of the BD buffers */ 200 unsigned int bd_size; /* size of BD buffer space */ 201 }; 202 203 static struct uart_driver ucc_uart_driver = { 204 .owner = THIS_MODULE, 205 .driver_name = "ucc_uart", 206 .dev_name = "ttyQE", 207 .major = SERIAL_QE_MAJOR, 208 .minor = SERIAL_QE_MINOR, 209 .nr = UCC_MAX_UART, 210 }; 211 212 /* 213 * Virtual to physical address translation. 214 * 215 * Given the virtual address for a character buffer, this function returns 216 * the physical (DMA) equivalent. 217 */ 218 static inline dma_addr_t cpu2qe_addr(void *addr, struct uart_qe_port *qe_port) 219 { 220 if (likely((addr >= qe_port->bd_virt)) && 221 (addr < (qe_port->bd_virt + qe_port->bd_size))) 222 return qe_port->bd_dma_addr + (addr - qe_port->bd_virt); 223 224 /* something nasty happened */ 225 printk(KERN_ERR "%s: addr=%p\n", __func__, addr); 226 BUG(); 227 return 0; 228 } 229 230 /* 231 * Physical to virtual address translation. 232 * 233 * Given the physical (DMA) address for a character buffer, this function 234 * returns the virtual equivalent. 235 */ 236 static inline void *qe2cpu_addr(dma_addr_t addr, struct uart_qe_port *qe_port) 237 { 238 /* sanity check */ 239 if (likely((addr >= qe_port->bd_dma_addr) && 240 (addr < (qe_port->bd_dma_addr + qe_port->bd_size)))) 241 return qe_port->bd_virt + (addr - qe_port->bd_dma_addr); 242 243 /* something nasty happened */ 244 printk(KERN_ERR "%s: addr=%llx\n", __func__, (u64)addr); 245 BUG(); 246 return NULL; 247 } 248 249 /* 250 * Return 1 if the QE is done transmitting all buffers for this port 251 * 252 * This function scans each BD in sequence. If we find a BD that is not 253 * ready (READY=1), then we return 0 indicating that the QE is still sending 254 * data. If we reach the last BD (WRAP=1), then we know we've scanned 255 * the entire list, and all BDs are done. 256 */ 257 static unsigned int qe_uart_tx_empty(struct uart_port *port) 258 { 259 struct uart_qe_port *qe_port = 260 container_of(port, struct uart_qe_port, port); 261 struct qe_bd *bdp = qe_port->tx_bd_base; 262 263 while (1) { 264 if (ioread16be(&bdp->status) & BD_SC_READY) 265 /* This BD is not done, so return "not done" */ 266 return 0; 267 268 if (ioread16be(&bdp->status) & BD_SC_WRAP) 269 /* 270 * This BD is done and it's the last one, so return 271 * "done" 272 */ 273 return 1; 274 275 bdp++; 276 } 277 } 278 279 /* 280 * Set the modem control lines 281 * 282 * Although the QE can control the modem control lines (e.g. CTS), we 283 * don't need that support. This function must exist, however, otherwise 284 * the kernel will panic. 285 */ 286 static void qe_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) 287 { 288 } 289 290 /* 291 * Get the current modem control line status 292 * 293 * Although the QE can control the modem control lines (e.g. CTS), this 294 * driver currently doesn't support that, so we always return Carrier 295 * Detect, Data Set Ready, and Clear To Send. 296 */ 297 static unsigned int qe_uart_get_mctrl(struct uart_port *port) 298 { 299 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; 300 } 301 302 /* 303 * Disable the transmit interrupt. 304 * 305 * Although this function is called "stop_tx", it does not actually stop 306 * transmission of data. Instead, it tells the QE to not generate an 307 * interrupt when the UCC is finished sending characters. 308 */ 309 static void qe_uart_stop_tx(struct uart_port *port) 310 { 311 struct uart_qe_port *qe_port = 312 container_of(port, struct uart_qe_port, port); 313 314 qe_clrbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX); 315 } 316 317 /* 318 * Transmit as many characters to the HW as possible. 319 * 320 * This function will attempt to stuff of all the characters from the 321 * kernel's transmit buffer into TX BDs. 322 * 323 * A return value of non-zero indicates that it successfully stuffed all 324 * characters from the kernel buffer. 325 * 326 * A return value of zero indicates that there are still characters in the 327 * kernel's buffer that have not been transmitted, but there are no more BDs 328 * available. This function should be called again after a BD has been made 329 * available. 330 */ 331 static int qe_uart_tx_pump(struct uart_qe_port *qe_port) 332 { 333 struct qe_bd *bdp; 334 unsigned char *p; 335 unsigned int count; 336 struct uart_port *port = &qe_port->port; 337 struct circ_buf *xmit = &port->state->xmit; 338 339 /* Handle xon/xoff */ 340 if (port->x_char) { 341 /* Pick next descriptor and fill from buffer */ 342 bdp = qe_port->tx_cur; 343 344 p = qe2cpu_addr(be32_to_cpu(bdp->buf), qe_port); 345 346 *p++ = port->x_char; 347 iowrite16be(1, &bdp->length); 348 qe_setbits_be16(&bdp->status, BD_SC_READY); 349 /* Get next BD. */ 350 if (ioread16be(&bdp->status) & BD_SC_WRAP) 351 bdp = qe_port->tx_bd_base; 352 else 353 bdp++; 354 qe_port->tx_cur = bdp; 355 356 port->icount.tx++; 357 port->x_char = 0; 358 return 1; 359 } 360 361 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { 362 qe_uart_stop_tx(port); 363 return 0; 364 } 365 366 /* Pick next descriptor and fill from buffer */ 367 bdp = qe_port->tx_cur; 368 369 while (!(ioread16be(&bdp->status) & BD_SC_READY) && 370 (xmit->tail != xmit->head)) { 371 count = 0; 372 p = qe2cpu_addr(be32_to_cpu(bdp->buf), qe_port); 373 while (count < qe_port->tx_fifosize) { 374 *p++ = xmit->buf[xmit->tail]; 375 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); 376 port->icount.tx++; 377 count++; 378 if (xmit->head == xmit->tail) 379 break; 380 } 381 382 iowrite16be(count, &bdp->length); 383 qe_setbits_be16(&bdp->status, BD_SC_READY); 384 385 /* Get next BD. */ 386 if (ioread16be(&bdp->status) & BD_SC_WRAP) 387 bdp = qe_port->tx_bd_base; 388 else 389 bdp++; 390 } 391 qe_port->tx_cur = bdp; 392 393 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) 394 uart_write_wakeup(port); 395 396 if (uart_circ_empty(xmit)) { 397 /* The kernel buffer is empty, so turn off TX interrupts. We 398 don't need to be told when the QE is finished transmitting 399 the data. */ 400 qe_uart_stop_tx(port); 401 return 0; 402 } 403 404 return 1; 405 } 406 407 /* 408 * Start transmitting data 409 * 410 * This function will start transmitting any available data, if the port 411 * isn't already transmitting data. 412 */ 413 static void qe_uart_start_tx(struct uart_port *port) 414 { 415 struct uart_qe_port *qe_port = 416 container_of(port, struct uart_qe_port, port); 417 418 /* If we currently are transmitting, then just return */ 419 if (ioread16be(&qe_port->uccp->uccm) & UCC_UART_UCCE_TX) 420 return; 421 422 /* Otherwise, pump the port and start transmission */ 423 if (qe_uart_tx_pump(qe_port)) 424 qe_setbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX); 425 } 426 427 /* 428 * Stop transmitting data 429 */ 430 static void qe_uart_stop_rx(struct uart_port *port) 431 { 432 struct uart_qe_port *qe_port = 433 container_of(port, struct uart_qe_port, port); 434 435 qe_clrbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX); 436 } 437 438 /* Start or stop sending break signal 439 * 440 * This function controls the sending of a break signal. If break_state=1, 441 * then we start sending a break signal. If break_state=0, then we stop 442 * sending the break signal. 443 */ 444 static void qe_uart_break_ctl(struct uart_port *port, int break_state) 445 { 446 struct uart_qe_port *qe_port = 447 container_of(port, struct uart_qe_port, port); 448 449 if (break_state) 450 ucc_slow_stop_tx(qe_port->us_private); 451 else 452 ucc_slow_restart_tx(qe_port->us_private); 453 } 454 455 /* ISR helper function for receiving character. 456 * 457 * This function is called by the ISR to handling receiving characters 458 */ 459 static void qe_uart_int_rx(struct uart_qe_port *qe_port) 460 { 461 int i; 462 unsigned char ch, *cp; 463 struct uart_port *port = &qe_port->port; 464 struct tty_port *tport = &port->state->port; 465 struct qe_bd *bdp; 466 u16 status; 467 unsigned int flg; 468 469 /* Just loop through the closed BDs and copy the characters into 470 * the buffer. 471 */ 472 bdp = qe_port->rx_cur; 473 while (1) { 474 status = ioread16be(&bdp->status); 475 476 /* If this one is empty, then we assume we've read them all */ 477 if (status & BD_SC_EMPTY) 478 break; 479 480 /* get number of characters, and check space in RX buffer */ 481 i = ioread16be(&bdp->length); 482 483 /* If we don't have enough room in RX buffer for the entire BD, 484 * then we try later, which will be the next RX interrupt. 485 */ 486 if (tty_buffer_request_room(tport, i) < i) { 487 dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n"); 488 return; 489 } 490 491 /* get pointer */ 492 cp = qe2cpu_addr(be32_to_cpu(bdp->buf), qe_port); 493 494 /* loop through the buffer */ 495 while (i-- > 0) { 496 ch = *cp++; 497 port->icount.rx++; 498 flg = TTY_NORMAL; 499 500 if (!i && status & 501 (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV)) 502 goto handle_error; 503 if (uart_handle_sysrq_char(port, ch)) 504 continue; 505 506 error_return: 507 tty_insert_flip_char(tport, ch, flg); 508 509 } 510 511 /* This BD is ready to be used again. Clear status. get next */ 512 qe_clrsetbits_be16(&bdp->status, 513 BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV | BD_SC_ID, 514 BD_SC_EMPTY); 515 if (ioread16be(&bdp->status) & BD_SC_WRAP) 516 bdp = qe_port->rx_bd_base; 517 else 518 bdp++; 519 520 } 521 522 /* Write back buffer pointer */ 523 qe_port->rx_cur = bdp; 524 525 /* Activate BH processing */ 526 tty_flip_buffer_push(tport); 527 528 return; 529 530 /* Error processing */ 531 532 handle_error: 533 /* Statistics */ 534 if (status & BD_SC_BR) 535 port->icount.brk++; 536 if (status & BD_SC_PR) 537 port->icount.parity++; 538 if (status & BD_SC_FR) 539 port->icount.frame++; 540 if (status & BD_SC_OV) 541 port->icount.overrun++; 542 543 /* Mask out ignored conditions */ 544 status &= port->read_status_mask; 545 546 /* Handle the remaining ones */ 547 if (status & BD_SC_BR) 548 flg = TTY_BREAK; 549 else if (status & BD_SC_PR) 550 flg = TTY_PARITY; 551 else if (status & BD_SC_FR) 552 flg = TTY_FRAME; 553 554 /* Overrun does not affect the current character ! */ 555 if (status & BD_SC_OV) 556 tty_insert_flip_char(tport, 0, TTY_OVERRUN); 557 port->sysrq = 0; 558 goto error_return; 559 } 560 561 /* Interrupt handler 562 * 563 * This interrupt handler is called after a BD is processed. 564 */ 565 static irqreturn_t qe_uart_int(int irq, void *data) 566 { 567 struct uart_qe_port *qe_port = (struct uart_qe_port *) data; 568 struct ucc_slow __iomem *uccp = qe_port->uccp; 569 u16 events; 570 571 /* Clear the interrupts */ 572 events = ioread16be(&uccp->ucce); 573 iowrite16be(events, &uccp->ucce); 574 575 if (events & UCC_UART_UCCE_BRKE) 576 uart_handle_break(&qe_port->port); 577 578 if (events & UCC_UART_UCCE_RX) 579 qe_uart_int_rx(qe_port); 580 581 if (events & UCC_UART_UCCE_TX) 582 qe_uart_tx_pump(qe_port); 583 584 return events ? IRQ_HANDLED : IRQ_NONE; 585 } 586 587 /* Initialize buffer descriptors 588 * 589 * This function initializes all of the RX and TX buffer descriptors. 590 */ 591 static void qe_uart_initbd(struct uart_qe_port *qe_port) 592 { 593 int i; 594 void *bd_virt; 595 struct qe_bd *bdp; 596 597 /* Set the physical address of the host memory buffers in the buffer 598 * descriptors, and the virtual address for us to work with. 599 */ 600 bd_virt = qe_port->bd_virt; 601 bdp = qe_port->rx_bd_base; 602 qe_port->rx_cur = qe_port->rx_bd_base; 603 for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) { 604 iowrite16be(BD_SC_EMPTY | BD_SC_INTRPT, &bdp->status); 605 iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf); 606 iowrite16be(0, &bdp->length); 607 bd_virt += qe_port->rx_fifosize; 608 bdp++; 609 } 610 611 /* */ 612 iowrite16be(BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT, &bdp->status); 613 iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf); 614 iowrite16be(0, &bdp->length); 615 616 /* Set the physical address of the host memory 617 * buffers in the buffer descriptors, and the 618 * virtual address for us to work with. 619 */ 620 bd_virt = qe_port->bd_virt + 621 L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize); 622 qe_port->tx_cur = qe_port->tx_bd_base; 623 bdp = qe_port->tx_bd_base; 624 for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) { 625 iowrite16be(BD_SC_INTRPT, &bdp->status); 626 iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf); 627 iowrite16be(0, &bdp->length); 628 bd_virt += qe_port->tx_fifosize; 629 bdp++; 630 } 631 632 /* Loopback requires the preamble bit to be set on the first TX BD */ 633 #ifdef LOOPBACK 634 qe_setbits_be16(&qe_port->tx_cur->status, BD_SC_P); 635 #endif 636 637 iowrite16be(BD_SC_WRAP | BD_SC_INTRPT, &bdp->status); 638 iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf); 639 iowrite16be(0, &bdp->length); 640 } 641 642 /* 643 * Initialize a UCC for UART. 644 * 645 * This function configures a given UCC to be used as a UART device. Basic 646 * UCC initialization is handled in qe_uart_request_port(). This function 647 * does all the UART-specific stuff. 648 */ 649 static void qe_uart_init_ucc(struct uart_qe_port *qe_port) 650 { 651 u32 cecr_subblock; 652 struct ucc_slow __iomem *uccp = qe_port->uccp; 653 struct ucc_uart_pram *uccup = qe_port->uccup; 654 655 unsigned int i; 656 657 /* First, disable TX and RX in the UCC */ 658 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX); 659 660 /* Program the UCC UART parameter RAM */ 661 iowrite8(UCC_BMR_GBL | UCC_BMR_BO_BE, &uccup->common.rbmr); 662 iowrite8(UCC_BMR_GBL | UCC_BMR_BO_BE, &uccup->common.tbmr); 663 iowrite16be(qe_port->rx_fifosize, &uccup->common.mrblr); 664 iowrite16be(0x10, &uccup->maxidl); 665 iowrite16be(1, &uccup->brkcr); 666 iowrite16be(0, &uccup->parec); 667 iowrite16be(0, &uccup->frmec); 668 iowrite16be(0, &uccup->nosec); 669 iowrite16be(0, &uccup->brkec); 670 iowrite16be(0, &uccup->uaddr[0]); 671 iowrite16be(0, &uccup->uaddr[1]); 672 iowrite16be(0, &uccup->toseq); 673 for (i = 0; i < 8; i++) 674 iowrite16be(0xC000, &uccup->cchars[i]); 675 iowrite16be(0xc0ff, &uccup->rccm); 676 677 /* Configure the GUMR registers for UART */ 678 if (soft_uart) { 679 /* Soft-UART requires a 1X multiplier for TX */ 680 qe_clrsetbits_be32(&uccp->gumr_l, 681 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK | UCC_SLOW_GUMR_L_RDCR_MASK, 682 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 | UCC_SLOW_GUMR_L_RDCR_16); 683 684 qe_clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW, 685 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX); 686 } else { 687 qe_clrsetbits_be32(&uccp->gumr_l, 688 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK | UCC_SLOW_GUMR_L_RDCR_MASK, 689 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 | UCC_SLOW_GUMR_L_RDCR_16); 690 691 qe_clrsetbits_be32(&uccp->gumr_h, 692 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX, 693 UCC_SLOW_GUMR_H_RFW); 694 } 695 696 #ifdef LOOPBACK 697 qe_clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK, 698 UCC_SLOW_GUMR_L_DIAG_LOOP); 699 qe_clrsetbits_be32(&uccp->gumr_h, 700 UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN, 701 UCC_SLOW_GUMR_H_CDS); 702 #endif 703 704 /* Disable rx interrupts and clear all pending events. */ 705 iowrite16be(0, &uccp->uccm); 706 iowrite16be(0xffff, &uccp->ucce); 707 iowrite16be(0x7e7e, &uccp->udsr); 708 709 /* Initialize UPSMR */ 710 iowrite16be(0, &uccp->upsmr); 711 712 if (soft_uart) { 713 iowrite16be(0x30, &uccup->supsmr); 714 iowrite16be(0, &uccup->res92); 715 iowrite32be(0, &uccup->rx_state); 716 iowrite32be(0, &uccup->rx_cnt); 717 iowrite8(0, &uccup->rx_bitmark); 718 iowrite8(10, &uccup->rx_length); 719 iowrite32be(0x4000, &uccup->dump_ptr); 720 iowrite8(0, &uccup->rx_temp_dlst_qe); 721 iowrite32be(0, &uccup->rx_frame_rem); 722 iowrite8(0, &uccup->rx_frame_rem_size); 723 /* Soft-UART requires TX to be 1X */ 724 iowrite8(UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1, 725 &uccup->tx_mode); 726 iowrite16be(0, &uccup->tx_state); 727 iowrite8(0, &uccup->resD4); 728 iowrite16be(0, &uccup->resD5); 729 730 /* Set UART mode. 731 * Enable receive and transmit. 732 */ 733 734 /* From the microcode errata: 735 * 1.GUMR_L register, set mode=0010 (QMC). 736 * 2.Set GUMR_H[17] bit. (UART/AHDLC mode). 737 * 3.Set GUMR_H[19:20] (Transparent mode) 738 * 4.Clear GUMR_H[26] (RFW) 739 * ... 740 * 6.Receiver must use 16x over sampling 741 */ 742 qe_clrsetbits_be32(&uccp->gumr_l, 743 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK | UCC_SLOW_GUMR_L_RDCR_MASK, 744 UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 | UCC_SLOW_GUMR_L_RDCR_16); 745 746 qe_clrsetbits_be32(&uccp->gumr_h, 747 UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN, 748 UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL); 749 750 #ifdef LOOPBACK 751 qe_clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK, 752 UCC_SLOW_GUMR_L_DIAG_LOOP); 753 qe_clrbits_be32(&uccp->gumr_h, 754 UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_CDS); 755 #endif 756 757 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num); 758 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock, 759 QE_CR_PROTOCOL_UNSPECIFIED, 0); 760 } else { 761 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num); 762 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock, 763 QE_CR_PROTOCOL_UART, 0); 764 } 765 } 766 767 /* 768 * Initialize the port. 769 */ 770 static int qe_uart_startup(struct uart_port *port) 771 { 772 struct uart_qe_port *qe_port = 773 container_of(port, struct uart_qe_port, port); 774 int ret; 775 776 /* 777 * If we're using Soft-UART mode, then we need to make sure the 778 * firmware has been uploaded first. 779 */ 780 if (soft_uart && !firmware_loaded) { 781 dev_err(port->dev, "Soft-UART firmware not uploaded\n"); 782 return -ENODEV; 783 } 784 785 qe_uart_initbd(qe_port); 786 qe_uart_init_ucc(qe_port); 787 788 /* Install interrupt handler. */ 789 ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart", 790 qe_port); 791 if (ret) { 792 dev_err(port->dev, "could not claim IRQ %u\n", port->irq); 793 return ret; 794 } 795 796 /* Startup rx-int */ 797 qe_setbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX); 798 ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX); 799 800 return 0; 801 } 802 803 /* 804 * Shutdown the port. 805 */ 806 static void qe_uart_shutdown(struct uart_port *port) 807 { 808 struct uart_qe_port *qe_port = 809 container_of(port, struct uart_qe_port, port); 810 struct ucc_slow __iomem *uccp = qe_port->uccp; 811 unsigned int timeout = 20; 812 813 /* Disable RX and TX */ 814 815 /* Wait for all the BDs marked sent */ 816 while (!qe_uart_tx_empty(port)) { 817 if (!--timeout) { 818 dev_warn(port->dev, "shutdown timeout\n"); 819 break; 820 } 821 set_current_state(TASK_UNINTERRUPTIBLE); 822 schedule_timeout(2); 823 } 824 825 if (qe_port->wait_closing) { 826 /* Wait a bit longer */ 827 set_current_state(TASK_UNINTERRUPTIBLE); 828 schedule_timeout(qe_port->wait_closing); 829 } 830 831 /* Stop uarts */ 832 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX); 833 qe_clrbits_be16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX); 834 835 /* Shut them really down and reinit buffer descriptors */ 836 ucc_slow_graceful_stop_tx(qe_port->us_private); 837 qe_uart_initbd(qe_port); 838 839 free_irq(port->irq, qe_port); 840 } 841 842 /* 843 * Set the serial port parameters. 844 */ 845 static void qe_uart_set_termios(struct uart_port *port, 846 struct ktermios *termios, struct ktermios *old) 847 { 848 struct uart_qe_port *qe_port = 849 container_of(port, struct uart_qe_port, port); 850 struct ucc_slow __iomem *uccp = qe_port->uccp; 851 unsigned int baud; 852 unsigned long flags; 853 u16 upsmr = ioread16be(&uccp->upsmr); 854 struct ucc_uart_pram __iomem *uccup = qe_port->uccup; 855 u16 supsmr = ioread16be(&uccup->supsmr); 856 u8 char_length = 2; /* 1 + CL + PEN + 1 + SL */ 857 858 /* Character length programmed into the mode register is the 859 * sum of: 1 start bit, number of data bits, 0 or 1 parity bit, 860 * 1 or 2 stop bits, minus 1. 861 * The value 'bits' counts this for us. 862 */ 863 864 /* byte size */ 865 upsmr &= UCC_UART_UPSMR_CL_MASK; 866 supsmr &= UCC_UART_SUPSMR_CL_MASK; 867 868 switch (termios->c_cflag & CSIZE) { 869 case CS5: 870 upsmr |= UCC_UART_UPSMR_CL_5; 871 supsmr |= UCC_UART_SUPSMR_CL_5; 872 char_length += 5; 873 break; 874 case CS6: 875 upsmr |= UCC_UART_UPSMR_CL_6; 876 supsmr |= UCC_UART_SUPSMR_CL_6; 877 char_length += 6; 878 break; 879 case CS7: 880 upsmr |= UCC_UART_UPSMR_CL_7; 881 supsmr |= UCC_UART_SUPSMR_CL_7; 882 char_length += 7; 883 break; 884 default: /* case CS8 */ 885 upsmr |= UCC_UART_UPSMR_CL_8; 886 supsmr |= UCC_UART_SUPSMR_CL_8; 887 char_length += 8; 888 break; 889 } 890 891 /* If CSTOPB is set, we want two stop bits */ 892 if (termios->c_cflag & CSTOPB) { 893 upsmr |= UCC_UART_UPSMR_SL; 894 supsmr |= UCC_UART_SUPSMR_SL; 895 char_length++; /* + SL */ 896 } 897 898 if (termios->c_cflag & PARENB) { 899 upsmr |= UCC_UART_UPSMR_PEN; 900 supsmr |= UCC_UART_SUPSMR_PEN; 901 char_length++; /* + PEN */ 902 903 if (!(termios->c_cflag & PARODD)) { 904 upsmr &= ~(UCC_UART_UPSMR_RPM_MASK | 905 UCC_UART_UPSMR_TPM_MASK); 906 upsmr |= UCC_UART_UPSMR_RPM_EVEN | 907 UCC_UART_UPSMR_TPM_EVEN; 908 supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK | 909 UCC_UART_SUPSMR_TPM_MASK); 910 supsmr |= UCC_UART_SUPSMR_RPM_EVEN | 911 UCC_UART_SUPSMR_TPM_EVEN; 912 } 913 } 914 915 /* 916 * Set up parity check flag 917 */ 918 port->read_status_mask = BD_SC_EMPTY | BD_SC_OV; 919 if (termios->c_iflag & INPCK) 920 port->read_status_mask |= BD_SC_FR | BD_SC_PR; 921 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) 922 port->read_status_mask |= BD_SC_BR; 923 924 /* 925 * Characters to ignore 926 */ 927 port->ignore_status_mask = 0; 928 if (termios->c_iflag & IGNPAR) 929 port->ignore_status_mask |= BD_SC_PR | BD_SC_FR; 930 if (termios->c_iflag & IGNBRK) { 931 port->ignore_status_mask |= BD_SC_BR; 932 /* 933 * If we're ignore parity and break indicators, ignore 934 * overruns too. (For real raw support). 935 */ 936 if (termios->c_iflag & IGNPAR) 937 port->ignore_status_mask |= BD_SC_OV; 938 } 939 /* 940 * !!! ignore all characters if CREAD is not set 941 */ 942 if ((termios->c_cflag & CREAD) == 0) 943 port->read_status_mask &= ~BD_SC_EMPTY; 944 945 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16); 946 947 /* Do we really need a spinlock here? */ 948 spin_lock_irqsave(&port->lock, flags); 949 950 /* Update the per-port timeout. */ 951 uart_update_timeout(port, termios->c_cflag, baud); 952 953 iowrite16be(upsmr, &uccp->upsmr); 954 if (soft_uart) { 955 iowrite16be(supsmr, &uccup->supsmr); 956 iowrite8(char_length, &uccup->rx_length); 957 958 /* Soft-UART requires a 1X multiplier for TX */ 959 qe_setbrg(qe_port->us_info.rx_clock, baud, 16); 960 qe_setbrg(qe_port->us_info.tx_clock, baud, 1); 961 } else { 962 qe_setbrg(qe_port->us_info.rx_clock, baud, 16); 963 qe_setbrg(qe_port->us_info.tx_clock, baud, 16); 964 } 965 966 spin_unlock_irqrestore(&port->lock, flags); 967 } 968 969 /* 970 * Return a pointer to a string that describes what kind of port this is. 971 */ 972 static const char *qe_uart_type(struct uart_port *port) 973 { 974 return "QE"; 975 } 976 977 /* 978 * Allocate any memory and I/O resources required by the port. 979 */ 980 static int qe_uart_request_port(struct uart_port *port) 981 { 982 int ret; 983 struct uart_qe_port *qe_port = 984 container_of(port, struct uart_qe_port, port); 985 struct ucc_slow_info *us_info = &qe_port->us_info; 986 struct ucc_slow_private *uccs; 987 unsigned int rx_size, tx_size; 988 void *bd_virt; 989 dma_addr_t bd_dma_addr = 0; 990 991 ret = ucc_slow_init(us_info, &uccs); 992 if (ret) { 993 dev_err(port->dev, "could not initialize UCC%u\n", 994 qe_port->ucc_num); 995 return ret; 996 } 997 998 qe_port->us_private = uccs; 999 qe_port->uccp = uccs->us_regs; 1000 qe_port->uccup = (struct ucc_uart_pram *) uccs->us_pram; 1001 qe_port->rx_bd_base = uccs->rx_bd; 1002 qe_port->tx_bd_base = uccs->tx_bd; 1003 1004 /* 1005 * Allocate the transmit and receive data buffers. 1006 */ 1007 1008 rx_size = L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize); 1009 tx_size = L1_CACHE_ALIGN(qe_port->tx_nrfifos * qe_port->tx_fifosize); 1010 1011 bd_virt = dma_alloc_coherent(port->dev, rx_size + tx_size, &bd_dma_addr, 1012 GFP_KERNEL); 1013 if (!bd_virt) { 1014 dev_err(port->dev, "could not allocate buffer descriptors\n"); 1015 return -ENOMEM; 1016 } 1017 1018 qe_port->bd_virt = bd_virt; 1019 qe_port->bd_dma_addr = bd_dma_addr; 1020 qe_port->bd_size = rx_size + tx_size; 1021 1022 qe_port->rx_buf = bd_virt; 1023 qe_port->tx_buf = qe_port->rx_buf + rx_size; 1024 1025 return 0; 1026 } 1027 1028 /* 1029 * Configure the port. 1030 * 1031 * We say we're a CPM-type port because that's mostly true. Once the device 1032 * is configured, this driver operates almost identically to the CPM serial 1033 * driver. 1034 */ 1035 static void qe_uart_config_port(struct uart_port *port, int flags) 1036 { 1037 if (flags & UART_CONFIG_TYPE) { 1038 port->type = PORT_CPM; 1039 qe_uart_request_port(port); 1040 } 1041 } 1042 1043 /* 1044 * Release any memory and I/O resources that were allocated in 1045 * qe_uart_request_port(). 1046 */ 1047 static void qe_uart_release_port(struct uart_port *port) 1048 { 1049 struct uart_qe_port *qe_port = 1050 container_of(port, struct uart_qe_port, port); 1051 struct ucc_slow_private *uccs = qe_port->us_private; 1052 1053 dma_free_coherent(port->dev, qe_port->bd_size, qe_port->bd_virt, 1054 qe_port->bd_dma_addr); 1055 1056 ucc_slow_free(uccs); 1057 } 1058 1059 /* 1060 * Verify that the data in serial_struct is suitable for this device. 1061 */ 1062 static int qe_uart_verify_port(struct uart_port *port, 1063 struct serial_struct *ser) 1064 { 1065 if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM) 1066 return -EINVAL; 1067 1068 if (ser->irq < 0 || ser->irq >= nr_irqs) 1069 return -EINVAL; 1070 1071 if (ser->baud_base < 9600) 1072 return -EINVAL; 1073 1074 return 0; 1075 } 1076 /* UART operations 1077 * 1078 * Details on these functions can be found in Documentation/driver-api/serial/driver.rst 1079 */ 1080 static const struct uart_ops qe_uart_pops = { 1081 .tx_empty = qe_uart_tx_empty, 1082 .set_mctrl = qe_uart_set_mctrl, 1083 .get_mctrl = qe_uart_get_mctrl, 1084 .stop_tx = qe_uart_stop_tx, 1085 .start_tx = qe_uart_start_tx, 1086 .stop_rx = qe_uart_stop_rx, 1087 .break_ctl = qe_uart_break_ctl, 1088 .startup = qe_uart_startup, 1089 .shutdown = qe_uart_shutdown, 1090 .set_termios = qe_uart_set_termios, 1091 .type = qe_uart_type, 1092 .release_port = qe_uart_release_port, 1093 .request_port = qe_uart_request_port, 1094 .config_port = qe_uart_config_port, 1095 .verify_port = qe_uart_verify_port, 1096 }; 1097 1098 1099 #ifdef CONFIG_PPC32 1100 /* 1101 * Obtain the SOC model number and revision level 1102 * 1103 * This function parses the device tree to obtain the SOC model. It then 1104 * reads the SVR register to the revision. 1105 * 1106 * The device tree stores the SOC model two different ways. 1107 * 1108 * The new way is: 1109 * 1110 * cpu@0 { 1111 * compatible = "PowerPC,8323"; 1112 * device_type = "cpu"; 1113 * ... 1114 * 1115 * 1116 * The old way is: 1117 * PowerPC,8323@0 { 1118 * device_type = "cpu"; 1119 * ... 1120 * 1121 * This code first checks the new way, and then the old way. 1122 */ 1123 static unsigned int soc_info(unsigned int *rev_h, unsigned int *rev_l) 1124 { 1125 struct device_node *np; 1126 const char *soc_string; 1127 unsigned int svr; 1128 unsigned int soc; 1129 1130 /* Find the CPU node */ 1131 np = of_find_node_by_type(NULL, "cpu"); 1132 if (!np) 1133 return 0; 1134 /* Find the compatible property */ 1135 soc_string = of_get_property(np, "compatible", NULL); 1136 if (!soc_string) 1137 /* No compatible property, so try the name. */ 1138 soc_string = np->name; 1139 1140 /* Extract the SOC number from the "PowerPC," string */ 1141 if ((sscanf(soc_string, "PowerPC,%u", &soc) != 1) || !soc) 1142 return 0; 1143 1144 /* Get the revision from the SVR */ 1145 svr = mfspr(SPRN_SVR); 1146 *rev_h = (svr >> 4) & 0xf; 1147 *rev_l = svr & 0xf; 1148 1149 return soc; 1150 } 1151 1152 /* 1153 * requst_firmware_nowait() callback function 1154 * 1155 * This function is called by the kernel when a firmware is made available, 1156 * or if it times out waiting for the firmware. 1157 */ 1158 static void uart_firmware_cont(const struct firmware *fw, void *context) 1159 { 1160 struct qe_firmware *firmware; 1161 struct device *dev = context; 1162 int ret; 1163 1164 if (!fw) { 1165 dev_err(dev, "firmware not found\n"); 1166 return; 1167 } 1168 1169 firmware = (struct qe_firmware *) fw->data; 1170 1171 if (firmware->header.length != fw->size) { 1172 dev_err(dev, "invalid firmware\n"); 1173 goto out; 1174 } 1175 1176 ret = qe_upload_firmware(firmware); 1177 if (ret) { 1178 dev_err(dev, "could not load firmware\n"); 1179 goto out; 1180 } 1181 1182 firmware_loaded = 1; 1183 out: 1184 release_firmware(fw); 1185 } 1186 1187 static int soft_uart_init(struct platform_device *ofdev) 1188 { 1189 struct device_node *np = ofdev->dev.of_node; 1190 struct qe_firmware_info *qe_fw_info; 1191 int ret; 1192 1193 if (of_find_property(np, "soft-uart", NULL)) { 1194 dev_dbg(&ofdev->dev, "using Soft-UART mode\n"); 1195 soft_uart = 1; 1196 } else { 1197 return 0; 1198 } 1199 1200 qe_fw_info = qe_get_firmware_info(); 1201 1202 /* Check if the firmware has been uploaded. */ 1203 if (qe_fw_info && strstr(qe_fw_info->id, "Soft-UART")) { 1204 firmware_loaded = 1; 1205 } else { 1206 char filename[32]; 1207 unsigned int soc; 1208 unsigned int rev_h; 1209 unsigned int rev_l; 1210 1211 soc = soc_info(&rev_h, &rev_l); 1212 if (!soc) { 1213 dev_err(&ofdev->dev, "unknown CPU model\n"); 1214 return -ENXIO; 1215 } 1216 sprintf(filename, "fsl_qe_ucode_uart_%u_%u%u.bin", 1217 soc, rev_h, rev_l); 1218 1219 dev_info(&ofdev->dev, "waiting for firmware %s\n", 1220 filename); 1221 1222 /* 1223 * We call request_firmware_nowait instead of 1224 * request_firmware so that the driver can load and 1225 * initialize the ports without holding up the rest of 1226 * the kernel. If hotplug support is enabled in the 1227 * kernel, then we use it. 1228 */ 1229 ret = request_firmware_nowait(THIS_MODULE, 1230 FW_ACTION_HOTPLUG, filename, &ofdev->dev, 1231 GFP_KERNEL, &ofdev->dev, uart_firmware_cont); 1232 if (ret) { 1233 dev_err(&ofdev->dev, 1234 "could not load firmware %s\n", 1235 filename); 1236 return ret; 1237 } 1238 } 1239 return 0; 1240 } 1241 1242 #else /* !CONFIG_PPC32 */ 1243 1244 static int soft_uart_init(struct platform_device *ofdev) 1245 { 1246 return 0; 1247 } 1248 1249 #endif 1250 1251 1252 static int ucc_uart_probe(struct platform_device *ofdev) 1253 { 1254 struct device_node *np = ofdev->dev.of_node; 1255 const char *sprop; /* String OF properties */ 1256 struct uart_qe_port *qe_port = NULL; 1257 struct resource res; 1258 u32 val; 1259 int ret; 1260 1261 /* 1262 * Determine if we need Soft-UART mode 1263 */ 1264 ret = soft_uart_init(ofdev); 1265 if (ret) 1266 return ret; 1267 1268 qe_port = kzalloc(sizeof(struct uart_qe_port), GFP_KERNEL); 1269 if (!qe_port) { 1270 dev_err(&ofdev->dev, "can't allocate QE port structure\n"); 1271 return -ENOMEM; 1272 } 1273 1274 /* Search for IRQ and mapbase */ 1275 ret = of_address_to_resource(np, 0, &res); 1276 if (ret) { 1277 dev_err(&ofdev->dev, "missing 'reg' property in device tree\n"); 1278 goto out_free; 1279 } 1280 if (!res.start) { 1281 dev_err(&ofdev->dev, "invalid 'reg' property in device tree\n"); 1282 ret = -EINVAL; 1283 goto out_free; 1284 } 1285 qe_port->port.mapbase = res.start; 1286 1287 /* Get the UCC number (device ID) */ 1288 /* UCCs are numbered 1-7 */ 1289 if (of_property_read_u32(np, "cell-index", &val)) { 1290 if (of_property_read_u32(np, "device-id", &val)) { 1291 dev_err(&ofdev->dev, "UCC is unspecified in device tree\n"); 1292 ret = -EINVAL; 1293 goto out_free; 1294 } 1295 } 1296 1297 if (val < 1 || val > UCC_MAX_NUM) { 1298 dev_err(&ofdev->dev, "no support for UCC%u\n", val); 1299 ret = -ENODEV; 1300 goto out_free; 1301 } 1302 qe_port->ucc_num = val - 1; 1303 1304 /* 1305 * In the future, we should not require the BRG to be specified in the 1306 * device tree. If no clock-source is specified, then just pick a BRG 1307 * to use. This requires a new QE library function that manages BRG 1308 * assignments. 1309 */ 1310 1311 sprop = of_get_property(np, "rx-clock-name", NULL); 1312 if (!sprop) { 1313 dev_err(&ofdev->dev, "missing rx-clock-name in device tree\n"); 1314 ret = -ENODEV; 1315 goto out_free; 1316 } 1317 1318 qe_port->us_info.rx_clock = qe_clock_source(sprop); 1319 if ((qe_port->us_info.rx_clock < QE_BRG1) || 1320 (qe_port->us_info.rx_clock > QE_BRG16)) { 1321 dev_err(&ofdev->dev, "rx-clock-name must be a BRG for UART\n"); 1322 ret = -ENODEV; 1323 goto out_free; 1324 } 1325 1326 #ifdef LOOPBACK 1327 /* In internal loopback mode, TX and RX must use the same clock */ 1328 qe_port->us_info.tx_clock = qe_port->us_info.rx_clock; 1329 #else 1330 sprop = of_get_property(np, "tx-clock-name", NULL); 1331 if (!sprop) { 1332 dev_err(&ofdev->dev, "missing tx-clock-name in device tree\n"); 1333 ret = -ENODEV; 1334 goto out_free; 1335 } 1336 qe_port->us_info.tx_clock = qe_clock_source(sprop); 1337 #endif 1338 if ((qe_port->us_info.tx_clock < QE_BRG1) || 1339 (qe_port->us_info.tx_clock > QE_BRG16)) { 1340 dev_err(&ofdev->dev, "tx-clock-name must be a BRG for UART\n"); 1341 ret = -ENODEV; 1342 goto out_free; 1343 } 1344 1345 /* Get the port number, numbered 0-3 */ 1346 if (of_property_read_u32(np, "port-number", &val)) { 1347 dev_err(&ofdev->dev, "missing port-number in device tree\n"); 1348 ret = -EINVAL; 1349 goto out_free; 1350 } 1351 qe_port->port.line = val; 1352 if (qe_port->port.line >= UCC_MAX_UART) { 1353 dev_err(&ofdev->dev, "port-number must be 0-%u\n", 1354 UCC_MAX_UART - 1); 1355 ret = -EINVAL; 1356 goto out_free; 1357 } 1358 1359 qe_port->port.irq = irq_of_parse_and_map(np, 0); 1360 if (qe_port->port.irq == 0) { 1361 dev_err(&ofdev->dev, "could not map IRQ for UCC%u\n", 1362 qe_port->ucc_num + 1); 1363 ret = -EINVAL; 1364 goto out_free; 1365 } 1366 1367 /* 1368 * Newer device trees have an "fsl,qe" compatible property for the QE 1369 * node, but we still need to support older device trees. 1370 */ 1371 np = of_find_compatible_node(NULL, NULL, "fsl,qe"); 1372 if (!np) { 1373 np = of_find_node_by_type(NULL, "qe"); 1374 if (!np) { 1375 dev_err(&ofdev->dev, "could not find 'qe' node\n"); 1376 ret = -EINVAL; 1377 goto out_free; 1378 } 1379 } 1380 1381 if (of_property_read_u32(np, "brg-frequency", &val)) { 1382 dev_err(&ofdev->dev, 1383 "missing brg-frequency in device tree\n"); 1384 ret = -EINVAL; 1385 goto out_np; 1386 } 1387 1388 if (val) 1389 qe_port->port.uartclk = val; 1390 else { 1391 if (!IS_ENABLED(CONFIG_PPC32)) { 1392 dev_err(&ofdev->dev, 1393 "invalid brg-frequency in device tree\n"); 1394 ret = -EINVAL; 1395 goto out_np; 1396 } 1397 1398 /* 1399 * Older versions of U-Boot do not initialize the brg-frequency 1400 * property, so in this case we assume the BRG frequency is 1401 * half the QE bus frequency. 1402 */ 1403 if (of_property_read_u32(np, "bus-frequency", &val)) { 1404 dev_err(&ofdev->dev, 1405 "missing QE bus-frequency in device tree\n"); 1406 ret = -EINVAL; 1407 goto out_np; 1408 } 1409 if (val) 1410 qe_port->port.uartclk = val / 2; 1411 else { 1412 dev_err(&ofdev->dev, 1413 "invalid QE bus-frequency in device tree\n"); 1414 ret = -EINVAL; 1415 goto out_np; 1416 } 1417 } 1418 1419 spin_lock_init(&qe_port->port.lock); 1420 qe_port->np = np; 1421 qe_port->port.dev = &ofdev->dev; 1422 qe_port->port.ops = &qe_uart_pops; 1423 qe_port->port.iotype = UPIO_MEM; 1424 1425 qe_port->tx_nrfifos = TX_NUM_FIFO; 1426 qe_port->tx_fifosize = TX_BUF_SIZE; 1427 qe_port->rx_nrfifos = RX_NUM_FIFO; 1428 qe_port->rx_fifosize = RX_BUF_SIZE; 1429 1430 qe_port->wait_closing = UCC_WAIT_CLOSING; 1431 qe_port->port.fifosize = 512; 1432 qe_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP; 1433 1434 qe_port->us_info.ucc_num = qe_port->ucc_num; 1435 qe_port->us_info.regs = (phys_addr_t) res.start; 1436 qe_port->us_info.irq = qe_port->port.irq; 1437 1438 qe_port->us_info.rx_bd_ring_len = qe_port->rx_nrfifos; 1439 qe_port->us_info.tx_bd_ring_len = qe_port->tx_nrfifos; 1440 1441 /* Make sure ucc_slow_init() initializes both TX and RX */ 1442 qe_port->us_info.init_tx = 1; 1443 qe_port->us_info.init_rx = 1; 1444 1445 /* Add the port to the uart sub-system. This will cause 1446 * qe_uart_config_port() to be called, so the us_info structure must 1447 * be initialized. 1448 */ 1449 ret = uart_add_one_port(&ucc_uart_driver, &qe_port->port); 1450 if (ret) { 1451 dev_err(&ofdev->dev, "could not add /dev/ttyQE%u\n", 1452 qe_port->port.line); 1453 goto out_np; 1454 } 1455 1456 platform_set_drvdata(ofdev, qe_port); 1457 1458 dev_info(&ofdev->dev, "UCC%u assigned to /dev/ttyQE%u\n", 1459 qe_port->ucc_num + 1, qe_port->port.line); 1460 1461 /* Display the mknod command for this device */ 1462 dev_dbg(&ofdev->dev, "mknod command is 'mknod /dev/ttyQE%u c %u %u'\n", 1463 qe_port->port.line, SERIAL_QE_MAJOR, 1464 SERIAL_QE_MINOR + qe_port->port.line); 1465 1466 return 0; 1467 out_np: 1468 of_node_put(np); 1469 out_free: 1470 kfree(qe_port); 1471 return ret; 1472 } 1473 1474 static int ucc_uart_remove(struct platform_device *ofdev) 1475 { 1476 struct uart_qe_port *qe_port = platform_get_drvdata(ofdev); 1477 1478 dev_info(&ofdev->dev, "removing /dev/ttyQE%u\n", qe_port->port.line); 1479 1480 uart_remove_one_port(&ucc_uart_driver, &qe_port->port); 1481 1482 kfree(qe_port); 1483 1484 return 0; 1485 } 1486 1487 static const struct of_device_id ucc_uart_match[] = { 1488 { 1489 .type = "serial", 1490 .compatible = "ucc_uart", 1491 }, 1492 { 1493 .compatible = "fsl,t1040-ucc-uart", 1494 }, 1495 {}, 1496 }; 1497 MODULE_DEVICE_TABLE(of, ucc_uart_match); 1498 1499 static struct platform_driver ucc_uart_of_driver = { 1500 .driver = { 1501 .name = "ucc_uart", 1502 .of_match_table = ucc_uart_match, 1503 }, 1504 .probe = ucc_uart_probe, 1505 .remove = ucc_uart_remove, 1506 }; 1507 1508 static int __init ucc_uart_init(void) 1509 { 1510 int ret; 1511 1512 printk(KERN_INFO "Freescale QUICC Engine UART device driver\n"); 1513 #ifdef LOOPBACK 1514 printk(KERN_INFO "ucc-uart: Using loopback mode\n"); 1515 #endif 1516 1517 ret = uart_register_driver(&ucc_uart_driver); 1518 if (ret) { 1519 printk(KERN_ERR "ucc-uart: could not register UART driver\n"); 1520 return ret; 1521 } 1522 1523 ret = platform_driver_register(&ucc_uart_of_driver); 1524 if (ret) { 1525 printk(KERN_ERR 1526 "ucc-uart: could not register platform driver\n"); 1527 uart_unregister_driver(&ucc_uart_driver); 1528 } 1529 1530 return ret; 1531 } 1532 1533 static void __exit ucc_uart_exit(void) 1534 { 1535 printk(KERN_INFO 1536 "Freescale QUICC Engine UART device driver unloading\n"); 1537 1538 platform_driver_unregister(&ucc_uart_of_driver); 1539 uart_unregister_driver(&ucc_uart_driver); 1540 } 1541 1542 module_init(ucc_uart_init); 1543 module_exit(ucc_uart_exit); 1544 1545 MODULE_DESCRIPTION("Freescale QUICC Engine (QE) UART"); 1546 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>"); 1547 MODULE_LICENSE("GPL v2"); 1548 MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_QE_MAJOR); 1549 1550