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/platform_device.h> 21 #include <linux/serial.h> 22 #include <linux/serial_core.h> 23 #include <linux/slab.h> 24 #include <linux/tty.h> 25 #include <linux/tty_flip.h> 26 #include <linux/io.h> 27 #include <linux/of.h> 28 #include <linux/of_address.h> 29 #include <linux/of_irq.h> 30 #include <linux/dma-mapping.h> 31 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 * Documentation/admin-guide/devices.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 __iomem *rx_bd_base; 193 struct qe_bd __iomem *rx_cur; 194 struct qe_bd __iomem *tx_bd_base; 195 struct qe_bd __iomem *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 __iomem *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 __iomem *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(ioread32be(&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) && !uart_circ_empty(xmit)) { 370 count = 0; 371 p = qe2cpu_addr(ioread32be(&bdp->buf), qe_port); 372 while (count < qe_port->tx_fifosize) { 373 *p++ = xmit->buf[xmit->tail]; 374 uart_xmit_advance(port, 1); 375 count++; 376 if (uart_circ_empty(xmit)) 377 break; 378 } 379 380 iowrite16be(count, &bdp->length); 381 qe_setbits_be16(&bdp->status, BD_SC_READY); 382 383 /* Get next BD. */ 384 if (ioread16be(&bdp->status) & BD_SC_WRAP) 385 bdp = qe_port->tx_bd_base; 386 else 387 bdp++; 388 } 389 qe_port->tx_cur = bdp; 390 391 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) 392 uart_write_wakeup(port); 393 394 if (uart_circ_empty(xmit)) { 395 /* The kernel buffer is empty, so turn off TX interrupts. We 396 don't need to be told when the QE is finished transmitting 397 the data. */ 398 qe_uart_stop_tx(port); 399 return 0; 400 } 401 402 return 1; 403 } 404 405 /* 406 * Start transmitting data 407 * 408 * This function will start transmitting any available data, if the port 409 * isn't already transmitting data. 410 */ 411 static void qe_uart_start_tx(struct uart_port *port) 412 { 413 struct uart_qe_port *qe_port = 414 container_of(port, struct uart_qe_port, port); 415 416 /* If we currently are transmitting, then just return */ 417 if (ioread16be(&qe_port->uccp->uccm) & UCC_UART_UCCE_TX) 418 return; 419 420 /* Otherwise, pump the port and start transmission */ 421 if (qe_uart_tx_pump(qe_port)) 422 qe_setbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX); 423 } 424 425 /* 426 * Stop transmitting data 427 */ 428 static void qe_uart_stop_rx(struct uart_port *port) 429 { 430 struct uart_qe_port *qe_port = 431 container_of(port, struct uart_qe_port, port); 432 433 qe_clrbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX); 434 } 435 436 /* Start or stop sending break signal 437 * 438 * This function controls the sending of a break signal. If break_state=1, 439 * then we start sending a break signal. If break_state=0, then we stop 440 * sending the break signal. 441 */ 442 static void qe_uart_break_ctl(struct uart_port *port, int break_state) 443 { 444 struct uart_qe_port *qe_port = 445 container_of(port, struct uart_qe_port, port); 446 447 if (break_state) 448 ucc_slow_stop_tx(qe_port->us_private); 449 else 450 ucc_slow_restart_tx(qe_port->us_private); 451 } 452 453 /* ISR helper function for receiving character. 454 * 455 * This function is called by the ISR to handling receiving characters 456 */ 457 static void qe_uart_int_rx(struct uart_qe_port *qe_port) 458 { 459 int i; 460 unsigned char ch, *cp; 461 struct uart_port *port = &qe_port->port; 462 struct tty_port *tport = &port->state->port; 463 struct qe_bd __iomem *bdp; 464 u16 status; 465 unsigned int flg; 466 467 /* Just loop through the closed BDs and copy the characters into 468 * the buffer. 469 */ 470 bdp = qe_port->rx_cur; 471 while (1) { 472 status = ioread16be(&bdp->status); 473 474 /* If this one is empty, then we assume we've read them all */ 475 if (status & BD_SC_EMPTY) 476 break; 477 478 /* get number of characters, and check space in RX buffer */ 479 i = ioread16be(&bdp->length); 480 481 /* If we don't have enough room in RX buffer for the entire BD, 482 * then we try later, which will be the next RX interrupt. 483 */ 484 if (tty_buffer_request_room(tport, i) < i) { 485 dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n"); 486 return; 487 } 488 489 /* get pointer */ 490 cp = qe2cpu_addr(ioread32be(&bdp->buf), qe_port); 491 492 /* loop through the buffer */ 493 while (i-- > 0) { 494 ch = *cp++; 495 port->icount.rx++; 496 flg = TTY_NORMAL; 497 498 if (!i && status & 499 (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV)) 500 goto handle_error; 501 if (uart_handle_sysrq_char(port, ch)) 502 continue; 503 504 error_return: 505 tty_insert_flip_char(tport, ch, flg); 506 507 } 508 509 /* This BD is ready to be used again. Clear status. get next */ 510 qe_clrsetbits_be16(&bdp->status, 511 BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV | BD_SC_ID, 512 BD_SC_EMPTY); 513 if (ioread16be(&bdp->status) & BD_SC_WRAP) 514 bdp = qe_port->rx_bd_base; 515 else 516 bdp++; 517 518 } 519 520 /* Write back buffer pointer */ 521 qe_port->rx_cur = bdp; 522 523 /* Activate BH processing */ 524 tty_flip_buffer_push(tport); 525 526 return; 527 528 /* Error processing */ 529 530 handle_error: 531 /* Statistics */ 532 if (status & BD_SC_BR) 533 port->icount.brk++; 534 if (status & BD_SC_PR) 535 port->icount.parity++; 536 if (status & BD_SC_FR) 537 port->icount.frame++; 538 if (status & BD_SC_OV) 539 port->icount.overrun++; 540 541 /* Mask out ignored conditions */ 542 status &= port->read_status_mask; 543 544 /* Handle the remaining ones */ 545 if (status & BD_SC_BR) 546 flg = TTY_BREAK; 547 else if (status & BD_SC_PR) 548 flg = TTY_PARITY; 549 else if (status & BD_SC_FR) 550 flg = TTY_FRAME; 551 552 /* Overrun does not affect the current character ! */ 553 if (status & BD_SC_OV) 554 tty_insert_flip_char(tport, 0, TTY_OVERRUN); 555 port->sysrq = 0; 556 goto error_return; 557 } 558 559 /* Interrupt handler 560 * 561 * This interrupt handler is called after a BD is processed. 562 */ 563 static irqreturn_t qe_uart_int(int irq, void *data) 564 { 565 struct uart_qe_port *qe_port = (struct uart_qe_port *) data; 566 struct ucc_slow __iomem *uccp = qe_port->uccp; 567 u16 events; 568 569 /* Clear the interrupts */ 570 events = ioread16be(&uccp->ucce); 571 iowrite16be(events, &uccp->ucce); 572 573 if (events & UCC_UART_UCCE_BRKE) 574 uart_handle_break(&qe_port->port); 575 576 if (events & UCC_UART_UCCE_RX) 577 qe_uart_int_rx(qe_port); 578 579 if (events & UCC_UART_UCCE_TX) 580 qe_uart_tx_pump(qe_port); 581 582 return events ? IRQ_HANDLED : IRQ_NONE; 583 } 584 585 /* Initialize buffer descriptors 586 * 587 * This function initializes all of the RX and TX buffer descriptors. 588 */ 589 static void qe_uart_initbd(struct uart_qe_port *qe_port) 590 { 591 int i; 592 void *bd_virt; 593 struct qe_bd __iomem *bdp; 594 595 /* Set the physical address of the host memory buffers in the buffer 596 * descriptors, and the virtual address for us to work with. 597 */ 598 bd_virt = qe_port->bd_virt; 599 bdp = qe_port->rx_bd_base; 600 qe_port->rx_cur = qe_port->rx_bd_base; 601 for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) { 602 iowrite16be(BD_SC_EMPTY | BD_SC_INTRPT, &bdp->status); 603 iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf); 604 iowrite16be(0, &bdp->length); 605 bd_virt += qe_port->rx_fifosize; 606 bdp++; 607 } 608 609 /* */ 610 iowrite16be(BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT, &bdp->status); 611 iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf); 612 iowrite16be(0, &bdp->length); 613 614 /* Set the physical address of the host memory 615 * buffers in the buffer descriptors, and the 616 * virtual address for us to work with. 617 */ 618 bd_virt = qe_port->bd_virt + 619 L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize); 620 qe_port->tx_cur = qe_port->tx_bd_base; 621 bdp = qe_port->tx_bd_base; 622 for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) { 623 iowrite16be(BD_SC_INTRPT, &bdp->status); 624 iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf); 625 iowrite16be(0, &bdp->length); 626 bd_virt += qe_port->tx_fifosize; 627 bdp++; 628 } 629 630 /* Loopback requires the preamble bit to be set on the first TX BD */ 631 #ifdef LOOPBACK 632 qe_setbits_be16(&qe_port->tx_cur->status, BD_SC_P); 633 #endif 634 635 iowrite16be(BD_SC_WRAP | BD_SC_INTRPT, &bdp->status); 636 iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf); 637 iowrite16be(0, &bdp->length); 638 } 639 640 /* 641 * Initialize a UCC for UART. 642 * 643 * This function configures a given UCC to be used as a UART device. Basic 644 * UCC initialization is handled in qe_uart_request_port(). This function 645 * does all the UART-specific stuff. 646 */ 647 static void qe_uart_init_ucc(struct uart_qe_port *qe_port) 648 { 649 u32 cecr_subblock; 650 struct ucc_slow __iomem *uccp = qe_port->uccp; 651 struct ucc_uart_pram __iomem *uccup = qe_port->uccup; 652 653 unsigned int i; 654 655 /* First, disable TX and RX in the UCC */ 656 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX); 657 658 /* Program the UCC UART parameter RAM */ 659 iowrite8(UCC_BMR_GBL | UCC_BMR_BO_BE, &uccup->common.rbmr); 660 iowrite8(UCC_BMR_GBL | UCC_BMR_BO_BE, &uccup->common.tbmr); 661 iowrite16be(qe_port->rx_fifosize, &uccup->common.mrblr); 662 iowrite16be(0x10, &uccup->maxidl); 663 iowrite16be(1, &uccup->brkcr); 664 iowrite16be(0, &uccup->parec); 665 iowrite16be(0, &uccup->frmec); 666 iowrite16be(0, &uccup->nosec); 667 iowrite16be(0, &uccup->brkec); 668 iowrite16be(0, &uccup->uaddr[0]); 669 iowrite16be(0, &uccup->uaddr[1]); 670 iowrite16be(0, &uccup->toseq); 671 for (i = 0; i < 8; i++) 672 iowrite16be(0xC000, &uccup->cchars[i]); 673 iowrite16be(0xc0ff, &uccup->rccm); 674 675 /* Configure the GUMR registers for UART */ 676 if (soft_uart) { 677 /* Soft-UART requires a 1X multiplier for TX */ 678 qe_clrsetbits_be32(&uccp->gumr_l, 679 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK | UCC_SLOW_GUMR_L_RDCR_MASK, 680 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 | UCC_SLOW_GUMR_L_RDCR_16); 681 682 qe_clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW, 683 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX); 684 } else { 685 qe_clrsetbits_be32(&uccp->gumr_l, 686 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK | UCC_SLOW_GUMR_L_RDCR_MASK, 687 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 | UCC_SLOW_GUMR_L_RDCR_16); 688 689 qe_clrsetbits_be32(&uccp->gumr_h, 690 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX, 691 UCC_SLOW_GUMR_H_RFW); 692 } 693 694 #ifdef LOOPBACK 695 qe_clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK, 696 UCC_SLOW_GUMR_L_DIAG_LOOP); 697 qe_clrsetbits_be32(&uccp->gumr_h, 698 UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN, 699 UCC_SLOW_GUMR_H_CDS); 700 #endif 701 702 /* Disable rx interrupts and clear all pending events. */ 703 iowrite16be(0, &uccp->uccm); 704 iowrite16be(0xffff, &uccp->ucce); 705 iowrite16be(0x7e7e, &uccp->udsr); 706 707 /* Initialize UPSMR */ 708 iowrite16be(0, &uccp->upsmr); 709 710 if (soft_uart) { 711 iowrite16be(0x30, &uccup->supsmr); 712 iowrite16be(0, &uccup->res92); 713 iowrite32be(0, &uccup->rx_state); 714 iowrite32be(0, &uccup->rx_cnt); 715 iowrite8(0, &uccup->rx_bitmark); 716 iowrite8(10, &uccup->rx_length); 717 iowrite32be(0x4000, &uccup->dump_ptr); 718 iowrite8(0, &uccup->rx_temp_dlst_qe); 719 iowrite32be(0, &uccup->rx_frame_rem); 720 iowrite8(0, &uccup->rx_frame_rem_size); 721 /* Soft-UART requires TX to be 1X */ 722 iowrite8(UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1, 723 &uccup->tx_mode); 724 iowrite16be(0, &uccup->tx_state); 725 iowrite8(0, &uccup->resD4); 726 iowrite16be(0, &uccup->resD5); 727 728 /* Set UART mode. 729 * Enable receive and transmit. 730 */ 731 732 /* From the microcode errata: 733 * 1.GUMR_L register, set mode=0010 (QMC). 734 * 2.Set GUMR_H[17] bit. (UART/AHDLC mode). 735 * 3.Set GUMR_H[19:20] (Transparent mode) 736 * 4.Clear GUMR_H[26] (RFW) 737 * ... 738 * 6.Receiver must use 16x over sampling 739 */ 740 qe_clrsetbits_be32(&uccp->gumr_l, 741 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK | UCC_SLOW_GUMR_L_RDCR_MASK, 742 UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 | UCC_SLOW_GUMR_L_RDCR_16); 743 744 qe_clrsetbits_be32(&uccp->gumr_h, 745 UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN, 746 UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL); 747 748 #ifdef LOOPBACK 749 qe_clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK, 750 UCC_SLOW_GUMR_L_DIAG_LOOP); 751 qe_clrbits_be32(&uccp->gumr_h, 752 UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_CDS); 753 #endif 754 755 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num); 756 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock, 757 QE_CR_PROTOCOL_UNSPECIFIED, 0); 758 } else { 759 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num); 760 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock, 761 QE_CR_PROTOCOL_UART, 0); 762 } 763 } 764 765 /* 766 * Initialize the port. 767 */ 768 static int qe_uart_startup(struct uart_port *port) 769 { 770 struct uart_qe_port *qe_port = 771 container_of(port, struct uart_qe_port, port); 772 int ret; 773 774 /* 775 * If we're using Soft-UART mode, then we need to make sure the 776 * firmware has been uploaded first. 777 */ 778 if (soft_uart && !firmware_loaded) { 779 dev_err(port->dev, "Soft-UART firmware not uploaded\n"); 780 return -ENODEV; 781 } 782 783 qe_uart_initbd(qe_port); 784 qe_uart_init_ucc(qe_port); 785 786 /* Install interrupt handler. */ 787 ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart", 788 qe_port); 789 if (ret) { 790 dev_err(port->dev, "could not claim IRQ %u\n", port->irq); 791 return ret; 792 } 793 794 /* Startup rx-int */ 795 qe_setbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX); 796 ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX); 797 798 return 0; 799 } 800 801 /* 802 * Shutdown the port. 803 */ 804 static void qe_uart_shutdown(struct uart_port *port) 805 { 806 struct uart_qe_port *qe_port = 807 container_of(port, struct uart_qe_port, port); 808 struct ucc_slow __iomem *uccp = qe_port->uccp; 809 unsigned int timeout = 20; 810 811 /* Disable RX and TX */ 812 813 /* Wait for all the BDs marked sent */ 814 while (!qe_uart_tx_empty(port)) { 815 if (!--timeout) { 816 dev_warn(port->dev, "shutdown timeout\n"); 817 break; 818 } 819 set_current_state(TASK_UNINTERRUPTIBLE); 820 schedule_timeout(2); 821 } 822 823 if (qe_port->wait_closing) { 824 /* Wait a bit longer */ 825 set_current_state(TASK_UNINTERRUPTIBLE); 826 schedule_timeout(qe_port->wait_closing); 827 } 828 829 /* Stop uarts */ 830 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX); 831 qe_clrbits_be16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX); 832 833 /* Shut them really down and reinit buffer descriptors */ 834 ucc_slow_graceful_stop_tx(qe_port->us_private); 835 qe_uart_initbd(qe_port); 836 837 free_irq(port->irq, qe_port); 838 } 839 840 /* 841 * Set the serial port parameters. 842 */ 843 static void qe_uart_set_termios(struct uart_port *port, 844 struct ktermios *termios, 845 const struct ktermios *old) 846 { 847 struct uart_qe_port *qe_port = 848 container_of(port, struct uart_qe_port, port); 849 struct ucc_slow __iomem *uccp = qe_port->uccp; 850 unsigned int baud; 851 unsigned long flags; 852 u16 upsmr = ioread16be(&uccp->upsmr); 853 struct ucc_uart_pram __iomem *uccup = qe_port->uccup; 854 u16 supsmr = ioread16be(&uccup->supsmr); 855 856 /* byte size */ 857 upsmr &= UCC_UART_UPSMR_CL_MASK; 858 supsmr &= UCC_UART_SUPSMR_CL_MASK; 859 860 switch (termios->c_cflag & CSIZE) { 861 case CS5: 862 upsmr |= UCC_UART_UPSMR_CL_5; 863 supsmr |= UCC_UART_SUPSMR_CL_5; 864 break; 865 case CS6: 866 upsmr |= UCC_UART_UPSMR_CL_6; 867 supsmr |= UCC_UART_SUPSMR_CL_6; 868 break; 869 case CS7: 870 upsmr |= UCC_UART_UPSMR_CL_7; 871 supsmr |= UCC_UART_SUPSMR_CL_7; 872 break; 873 default: /* case CS8 */ 874 upsmr |= UCC_UART_UPSMR_CL_8; 875 supsmr |= UCC_UART_SUPSMR_CL_8; 876 break; 877 } 878 879 /* If CSTOPB is set, we want two stop bits */ 880 if (termios->c_cflag & CSTOPB) { 881 upsmr |= UCC_UART_UPSMR_SL; 882 supsmr |= UCC_UART_SUPSMR_SL; 883 } 884 885 if (termios->c_cflag & PARENB) { 886 upsmr |= UCC_UART_UPSMR_PEN; 887 supsmr |= UCC_UART_SUPSMR_PEN; 888 889 if (!(termios->c_cflag & PARODD)) { 890 upsmr &= ~(UCC_UART_UPSMR_RPM_MASK | 891 UCC_UART_UPSMR_TPM_MASK); 892 upsmr |= UCC_UART_UPSMR_RPM_EVEN | 893 UCC_UART_UPSMR_TPM_EVEN; 894 supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK | 895 UCC_UART_SUPSMR_TPM_MASK); 896 supsmr |= UCC_UART_SUPSMR_RPM_EVEN | 897 UCC_UART_SUPSMR_TPM_EVEN; 898 } 899 } 900 901 /* 902 * Set up parity check flag 903 */ 904 port->read_status_mask = BD_SC_EMPTY | BD_SC_OV; 905 if (termios->c_iflag & INPCK) 906 port->read_status_mask |= BD_SC_FR | BD_SC_PR; 907 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) 908 port->read_status_mask |= BD_SC_BR; 909 910 /* 911 * Characters to ignore 912 */ 913 port->ignore_status_mask = 0; 914 if (termios->c_iflag & IGNPAR) 915 port->ignore_status_mask |= BD_SC_PR | BD_SC_FR; 916 if (termios->c_iflag & IGNBRK) { 917 port->ignore_status_mask |= BD_SC_BR; 918 /* 919 * If we're ignore parity and break indicators, ignore 920 * overruns too. (For real raw support). 921 */ 922 if (termios->c_iflag & IGNPAR) 923 port->ignore_status_mask |= BD_SC_OV; 924 } 925 /* 926 * !!! ignore all characters if CREAD is not set 927 */ 928 if ((termios->c_cflag & CREAD) == 0) 929 port->read_status_mask &= ~BD_SC_EMPTY; 930 931 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16); 932 933 /* Do we really need a spinlock here? */ 934 uart_port_lock_irqsave(port, &flags); 935 936 /* Update the per-port timeout. */ 937 uart_update_timeout(port, termios->c_cflag, baud); 938 939 iowrite16be(upsmr, &uccp->upsmr); 940 if (soft_uart) { 941 iowrite16be(supsmr, &uccup->supsmr); 942 iowrite8(tty_get_frame_size(termios->c_cflag), &uccup->rx_length); 943 944 /* Soft-UART requires a 1X multiplier for TX */ 945 qe_setbrg(qe_port->us_info.rx_clock, baud, 16); 946 qe_setbrg(qe_port->us_info.tx_clock, baud, 1); 947 } else { 948 qe_setbrg(qe_port->us_info.rx_clock, baud, 16); 949 qe_setbrg(qe_port->us_info.tx_clock, baud, 16); 950 } 951 952 uart_port_unlock_irqrestore(port, flags); 953 } 954 955 /* 956 * Return a pointer to a string that describes what kind of port this is. 957 */ 958 static const char *qe_uart_type(struct uart_port *port) 959 { 960 return "QE"; 961 } 962 963 /* 964 * Allocate any memory and I/O resources required by the port. 965 */ 966 static int qe_uart_request_port(struct uart_port *port) 967 { 968 int ret; 969 struct uart_qe_port *qe_port = 970 container_of(port, struct uart_qe_port, port); 971 struct ucc_slow_info *us_info = &qe_port->us_info; 972 struct ucc_slow_private *uccs; 973 unsigned int rx_size, tx_size; 974 void *bd_virt; 975 dma_addr_t bd_dma_addr = 0; 976 977 ret = ucc_slow_init(us_info, &uccs); 978 if (ret) { 979 dev_err(port->dev, "could not initialize UCC%u\n", 980 qe_port->ucc_num); 981 return ret; 982 } 983 984 qe_port->us_private = uccs; 985 qe_port->uccp = uccs->us_regs; 986 qe_port->uccup = (struct ucc_uart_pram __iomem *)uccs->us_pram; 987 qe_port->rx_bd_base = uccs->rx_bd; 988 qe_port->tx_bd_base = uccs->tx_bd; 989 990 /* 991 * Allocate the transmit and receive data buffers. 992 */ 993 994 rx_size = L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize); 995 tx_size = L1_CACHE_ALIGN(qe_port->tx_nrfifos * qe_port->tx_fifosize); 996 997 bd_virt = dma_alloc_coherent(port->dev, rx_size + tx_size, &bd_dma_addr, 998 GFP_KERNEL); 999 if (!bd_virt) { 1000 dev_err(port->dev, "could not allocate buffer descriptors\n"); 1001 return -ENOMEM; 1002 } 1003 1004 qe_port->bd_virt = bd_virt; 1005 qe_port->bd_dma_addr = bd_dma_addr; 1006 qe_port->bd_size = rx_size + tx_size; 1007 1008 qe_port->rx_buf = bd_virt; 1009 qe_port->tx_buf = qe_port->rx_buf + rx_size; 1010 1011 return 0; 1012 } 1013 1014 /* 1015 * Configure the port. 1016 * 1017 * We say we're a CPM-type port because that's mostly true. Once the device 1018 * is configured, this driver operates almost identically to the CPM serial 1019 * driver. 1020 */ 1021 static void qe_uart_config_port(struct uart_port *port, int flags) 1022 { 1023 if (flags & UART_CONFIG_TYPE) { 1024 port->type = PORT_CPM; 1025 qe_uart_request_port(port); 1026 } 1027 } 1028 1029 /* 1030 * Release any memory and I/O resources that were allocated in 1031 * qe_uart_request_port(). 1032 */ 1033 static void qe_uart_release_port(struct uart_port *port) 1034 { 1035 struct uart_qe_port *qe_port = 1036 container_of(port, struct uart_qe_port, port); 1037 struct ucc_slow_private *uccs = qe_port->us_private; 1038 1039 dma_free_coherent(port->dev, qe_port->bd_size, qe_port->bd_virt, 1040 qe_port->bd_dma_addr); 1041 1042 ucc_slow_free(uccs); 1043 } 1044 1045 /* 1046 * Verify that the data in serial_struct is suitable for this device. 1047 */ 1048 static int qe_uart_verify_port(struct uart_port *port, 1049 struct serial_struct *ser) 1050 { 1051 if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM) 1052 return -EINVAL; 1053 1054 if (ser->irq < 0 || ser->irq >= nr_irqs) 1055 return -EINVAL; 1056 1057 if (ser->baud_base < 9600) 1058 return -EINVAL; 1059 1060 return 0; 1061 } 1062 /* UART operations 1063 * 1064 * Details on these functions can be found in Documentation/driver-api/serial/driver.rst 1065 */ 1066 static const struct uart_ops qe_uart_pops = { 1067 .tx_empty = qe_uart_tx_empty, 1068 .set_mctrl = qe_uart_set_mctrl, 1069 .get_mctrl = qe_uart_get_mctrl, 1070 .stop_tx = qe_uart_stop_tx, 1071 .start_tx = qe_uart_start_tx, 1072 .stop_rx = qe_uart_stop_rx, 1073 .break_ctl = qe_uart_break_ctl, 1074 .startup = qe_uart_startup, 1075 .shutdown = qe_uart_shutdown, 1076 .set_termios = qe_uart_set_termios, 1077 .type = qe_uart_type, 1078 .release_port = qe_uart_release_port, 1079 .request_port = qe_uart_request_port, 1080 .config_port = qe_uart_config_port, 1081 .verify_port = qe_uart_verify_port, 1082 }; 1083 1084 1085 #ifdef CONFIG_PPC32 1086 /* 1087 * Obtain the SOC model number and revision level 1088 * 1089 * This function parses the device tree to obtain the SOC model. It then 1090 * reads the SVR register to the revision. 1091 * 1092 * The device tree stores the SOC model two different ways. 1093 * 1094 * The new way is: 1095 * 1096 * cpu@0 { 1097 * compatible = "PowerPC,8323"; 1098 * device_type = "cpu"; 1099 * ... 1100 * 1101 * 1102 * The old way is: 1103 * PowerPC,8323@0 { 1104 * device_type = "cpu"; 1105 * ... 1106 * 1107 * This code first checks the new way, and then the old way. 1108 */ 1109 static unsigned int soc_info(unsigned int *rev_h, unsigned int *rev_l) 1110 { 1111 struct device_node *np; 1112 const char *soc_string; 1113 unsigned int svr; 1114 unsigned int soc; 1115 1116 /* Find the CPU node */ 1117 np = of_find_node_by_type(NULL, "cpu"); 1118 if (!np) 1119 return 0; 1120 /* Find the compatible property */ 1121 soc_string = of_get_property(np, "compatible", NULL); 1122 if (!soc_string) 1123 /* No compatible property, so try the name. */ 1124 soc_string = np->name; 1125 1126 of_node_put(np); 1127 1128 /* Extract the SOC number from the "PowerPC," string */ 1129 if ((sscanf(soc_string, "PowerPC,%u", &soc) != 1) || !soc) 1130 return 0; 1131 1132 /* Get the revision from the SVR */ 1133 svr = mfspr(SPRN_SVR); 1134 *rev_h = (svr >> 4) & 0xf; 1135 *rev_l = svr & 0xf; 1136 1137 return soc; 1138 } 1139 1140 /* 1141 * requst_firmware_nowait() callback function 1142 * 1143 * This function is called by the kernel when a firmware is made available, 1144 * or if it times out waiting for the firmware. 1145 */ 1146 static void uart_firmware_cont(const struct firmware *fw, void *context) 1147 { 1148 struct qe_firmware *firmware; 1149 struct device *dev = context; 1150 int ret; 1151 1152 if (!fw) { 1153 dev_err(dev, "firmware not found\n"); 1154 return; 1155 } 1156 1157 firmware = (struct qe_firmware *) fw->data; 1158 1159 if (be32_to_cpu(firmware->header.length) != fw->size) { 1160 dev_err(dev, "invalid firmware\n"); 1161 goto out; 1162 } 1163 1164 ret = qe_upload_firmware(firmware); 1165 if (ret) { 1166 dev_err(dev, "could not load firmware\n"); 1167 goto out; 1168 } 1169 1170 firmware_loaded = 1; 1171 out: 1172 release_firmware(fw); 1173 } 1174 1175 static int soft_uart_init(struct platform_device *ofdev) 1176 { 1177 struct device_node *np = ofdev->dev.of_node; 1178 struct qe_firmware_info *qe_fw_info; 1179 int ret; 1180 1181 if (of_property_read_bool(np, "soft-uart")) { 1182 dev_dbg(&ofdev->dev, "using Soft-UART mode\n"); 1183 soft_uart = 1; 1184 } else { 1185 return 0; 1186 } 1187 1188 qe_fw_info = qe_get_firmware_info(); 1189 1190 /* Check if the firmware has been uploaded. */ 1191 if (qe_fw_info && strstr(qe_fw_info->id, "Soft-UART")) { 1192 firmware_loaded = 1; 1193 } else { 1194 char filename[32]; 1195 unsigned int soc; 1196 unsigned int rev_h; 1197 unsigned int rev_l; 1198 1199 soc = soc_info(&rev_h, &rev_l); 1200 if (!soc) { 1201 dev_err(&ofdev->dev, "unknown CPU model\n"); 1202 return -ENXIO; 1203 } 1204 sprintf(filename, "fsl_qe_ucode_uart_%u_%u%u.bin", 1205 soc, rev_h, rev_l); 1206 1207 dev_info(&ofdev->dev, "waiting for firmware %s\n", 1208 filename); 1209 1210 /* 1211 * We call request_firmware_nowait instead of 1212 * request_firmware so that the driver can load and 1213 * initialize the ports without holding up the rest of 1214 * the kernel. If hotplug support is enabled in the 1215 * kernel, then we use it. 1216 */ 1217 ret = request_firmware_nowait(THIS_MODULE, 1218 FW_ACTION_UEVENT, filename, &ofdev->dev, 1219 GFP_KERNEL, &ofdev->dev, uart_firmware_cont); 1220 if (ret) { 1221 dev_err(&ofdev->dev, 1222 "could not load firmware %s\n", 1223 filename); 1224 return ret; 1225 } 1226 } 1227 return 0; 1228 } 1229 1230 #else /* !CONFIG_PPC32 */ 1231 1232 static int soft_uart_init(struct platform_device *ofdev) 1233 { 1234 return 0; 1235 } 1236 1237 #endif 1238 1239 1240 static int ucc_uart_probe(struct platform_device *ofdev) 1241 { 1242 struct device_node *np = ofdev->dev.of_node; 1243 const char *sprop; /* String OF properties */ 1244 struct uart_qe_port *qe_port = NULL; 1245 struct resource res; 1246 u32 val; 1247 int ret; 1248 1249 /* 1250 * Determine if we need Soft-UART mode 1251 */ 1252 ret = soft_uart_init(ofdev); 1253 if (ret) 1254 return ret; 1255 1256 qe_port = kzalloc(sizeof(struct uart_qe_port), GFP_KERNEL); 1257 if (!qe_port) { 1258 dev_err(&ofdev->dev, "can't allocate QE port structure\n"); 1259 return -ENOMEM; 1260 } 1261 1262 /* Search for IRQ and mapbase */ 1263 ret = of_address_to_resource(np, 0, &res); 1264 if (ret) { 1265 dev_err(&ofdev->dev, "missing 'reg' property in device tree\n"); 1266 goto out_free; 1267 } 1268 if (!res.start) { 1269 dev_err(&ofdev->dev, "invalid 'reg' property in device tree\n"); 1270 ret = -EINVAL; 1271 goto out_free; 1272 } 1273 qe_port->port.mapbase = res.start; 1274 1275 /* Get the UCC number (device ID) */ 1276 /* UCCs are numbered 1-7 */ 1277 if (of_property_read_u32(np, "cell-index", &val)) { 1278 if (of_property_read_u32(np, "device-id", &val)) { 1279 dev_err(&ofdev->dev, "UCC is unspecified in device tree\n"); 1280 ret = -EINVAL; 1281 goto out_free; 1282 } 1283 } 1284 1285 if (val < 1 || val > UCC_MAX_NUM) { 1286 dev_err(&ofdev->dev, "no support for UCC%u\n", val); 1287 ret = -ENODEV; 1288 goto out_free; 1289 } 1290 qe_port->ucc_num = val - 1; 1291 1292 /* 1293 * In the future, we should not require the BRG to be specified in the 1294 * device tree. If no clock-source is specified, then just pick a BRG 1295 * to use. This requires a new QE library function that manages BRG 1296 * assignments. 1297 */ 1298 1299 sprop = of_get_property(np, "rx-clock-name", NULL); 1300 if (!sprop) { 1301 dev_err(&ofdev->dev, "missing rx-clock-name in device tree\n"); 1302 ret = -ENODEV; 1303 goto out_free; 1304 } 1305 1306 qe_port->us_info.rx_clock = qe_clock_source(sprop); 1307 if ((qe_port->us_info.rx_clock < QE_BRG1) || 1308 (qe_port->us_info.rx_clock > QE_BRG16)) { 1309 dev_err(&ofdev->dev, "rx-clock-name must be a BRG for UART\n"); 1310 ret = -ENODEV; 1311 goto out_free; 1312 } 1313 1314 #ifdef LOOPBACK 1315 /* In internal loopback mode, TX and RX must use the same clock */ 1316 qe_port->us_info.tx_clock = qe_port->us_info.rx_clock; 1317 #else 1318 sprop = of_get_property(np, "tx-clock-name", NULL); 1319 if (!sprop) { 1320 dev_err(&ofdev->dev, "missing tx-clock-name in device tree\n"); 1321 ret = -ENODEV; 1322 goto out_free; 1323 } 1324 qe_port->us_info.tx_clock = qe_clock_source(sprop); 1325 #endif 1326 if ((qe_port->us_info.tx_clock < QE_BRG1) || 1327 (qe_port->us_info.tx_clock > QE_BRG16)) { 1328 dev_err(&ofdev->dev, "tx-clock-name must be a BRG for UART\n"); 1329 ret = -ENODEV; 1330 goto out_free; 1331 } 1332 1333 /* Get the port number, numbered 0-3 */ 1334 if (of_property_read_u32(np, "port-number", &val)) { 1335 dev_err(&ofdev->dev, "missing port-number in device tree\n"); 1336 ret = -EINVAL; 1337 goto out_free; 1338 } 1339 qe_port->port.line = val; 1340 if (qe_port->port.line >= UCC_MAX_UART) { 1341 dev_err(&ofdev->dev, "port-number must be 0-%u\n", 1342 UCC_MAX_UART - 1); 1343 ret = -EINVAL; 1344 goto out_free; 1345 } 1346 1347 qe_port->port.irq = irq_of_parse_and_map(np, 0); 1348 if (qe_port->port.irq == 0) { 1349 dev_err(&ofdev->dev, "could not map IRQ for UCC%u\n", 1350 qe_port->ucc_num + 1); 1351 ret = -EINVAL; 1352 goto out_free; 1353 } 1354 1355 /* 1356 * Newer device trees have an "fsl,qe" compatible property for the QE 1357 * node, but we still need to support older device trees. 1358 */ 1359 np = of_find_compatible_node(NULL, NULL, "fsl,qe"); 1360 if (!np) { 1361 np = of_find_node_by_type(NULL, "qe"); 1362 if (!np) { 1363 dev_err(&ofdev->dev, "could not find 'qe' node\n"); 1364 ret = -EINVAL; 1365 goto out_free; 1366 } 1367 } 1368 1369 if (of_property_read_u32(np, "brg-frequency", &val)) { 1370 dev_err(&ofdev->dev, 1371 "missing brg-frequency in device tree\n"); 1372 ret = -EINVAL; 1373 goto out_np; 1374 } 1375 1376 if (val) 1377 qe_port->port.uartclk = val; 1378 else { 1379 if (!IS_ENABLED(CONFIG_PPC32)) { 1380 dev_err(&ofdev->dev, 1381 "invalid brg-frequency in device tree\n"); 1382 ret = -EINVAL; 1383 goto out_np; 1384 } 1385 1386 /* 1387 * Older versions of U-Boot do not initialize the brg-frequency 1388 * property, so in this case we assume the BRG frequency is 1389 * half the QE bus frequency. 1390 */ 1391 if (of_property_read_u32(np, "bus-frequency", &val)) { 1392 dev_err(&ofdev->dev, 1393 "missing QE bus-frequency in device tree\n"); 1394 ret = -EINVAL; 1395 goto out_np; 1396 } 1397 if (val) 1398 qe_port->port.uartclk = val / 2; 1399 else { 1400 dev_err(&ofdev->dev, 1401 "invalid QE bus-frequency in device tree\n"); 1402 ret = -EINVAL; 1403 goto out_np; 1404 } 1405 } 1406 1407 spin_lock_init(&qe_port->port.lock); 1408 qe_port->np = np; 1409 qe_port->port.dev = &ofdev->dev; 1410 qe_port->port.ops = &qe_uart_pops; 1411 qe_port->port.iotype = UPIO_MEM; 1412 1413 qe_port->tx_nrfifos = TX_NUM_FIFO; 1414 qe_port->tx_fifosize = TX_BUF_SIZE; 1415 qe_port->rx_nrfifos = RX_NUM_FIFO; 1416 qe_port->rx_fifosize = RX_BUF_SIZE; 1417 1418 qe_port->wait_closing = UCC_WAIT_CLOSING; 1419 qe_port->port.fifosize = 512; 1420 qe_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP; 1421 1422 qe_port->us_info.ucc_num = qe_port->ucc_num; 1423 qe_port->us_info.regs = (phys_addr_t) res.start; 1424 qe_port->us_info.irq = qe_port->port.irq; 1425 1426 qe_port->us_info.rx_bd_ring_len = qe_port->rx_nrfifos; 1427 qe_port->us_info.tx_bd_ring_len = qe_port->tx_nrfifos; 1428 1429 /* Make sure ucc_slow_init() initializes both TX and RX */ 1430 qe_port->us_info.init_tx = 1; 1431 qe_port->us_info.init_rx = 1; 1432 1433 /* Add the port to the uart sub-system. This will cause 1434 * qe_uart_config_port() to be called, so the us_info structure must 1435 * be initialized. 1436 */ 1437 ret = uart_add_one_port(&ucc_uart_driver, &qe_port->port); 1438 if (ret) { 1439 dev_err(&ofdev->dev, "could not add /dev/ttyQE%u\n", 1440 qe_port->port.line); 1441 goto out_np; 1442 } 1443 1444 platform_set_drvdata(ofdev, qe_port); 1445 1446 dev_info(&ofdev->dev, "UCC%u assigned to /dev/ttyQE%u\n", 1447 qe_port->ucc_num + 1, qe_port->port.line); 1448 1449 /* Display the mknod command for this device */ 1450 dev_dbg(&ofdev->dev, "mknod command is 'mknod /dev/ttyQE%u c %u %u'\n", 1451 qe_port->port.line, SERIAL_QE_MAJOR, 1452 SERIAL_QE_MINOR + qe_port->port.line); 1453 1454 return 0; 1455 out_np: 1456 of_node_put(np); 1457 out_free: 1458 kfree(qe_port); 1459 return ret; 1460 } 1461 1462 static void ucc_uart_remove(struct platform_device *ofdev) 1463 { 1464 struct uart_qe_port *qe_port = platform_get_drvdata(ofdev); 1465 1466 dev_info(&ofdev->dev, "removing /dev/ttyQE%u\n", qe_port->port.line); 1467 1468 uart_remove_one_port(&ucc_uart_driver, &qe_port->port); 1469 1470 of_node_put(qe_port->np); 1471 1472 kfree(qe_port); 1473 } 1474 1475 static const struct of_device_id ucc_uart_match[] = { 1476 { 1477 .type = "serial", 1478 .compatible = "ucc_uart", 1479 }, 1480 { 1481 .compatible = "fsl,t1040-ucc-uart", 1482 }, 1483 {}, 1484 }; 1485 MODULE_DEVICE_TABLE(of, ucc_uart_match); 1486 1487 static struct platform_driver ucc_uart_of_driver = { 1488 .driver = { 1489 .name = "ucc_uart", 1490 .of_match_table = ucc_uart_match, 1491 }, 1492 .probe = ucc_uart_probe, 1493 .remove_new = ucc_uart_remove, 1494 }; 1495 1496 static int __init ucc_uart_init(void) 1497 { 1498 int ret; 1499 1500 printk(KERN_INFO "Freescale QUICC Engine UART device driver\n"); 1501 #ifdef LOOPBACK 1502 printk(KERN_INFO "ucc-uart: Using loopback mode\n"); 1503 #endif 1504 1505 ret = uart_register_driver(&ucc_uart_driver); 1506 if (ret) { 1507 printk(KERN_ERR "ucc-uart: could not register UART driver\n"); 1508 return ret; 1509 } 1510 1511 ret = platform_driver_register(&ucc_uart_of_driver); 1512 if (ret) { 1513 printk(KERN_ERR 1514 "ucc-uart: could not register platform driver\n"); 1515 uart_unregister_driver(&ucc_uart_driver); 1516 } 1517 1518 return ret; 1519 } 1520 1521 static void __exit ucc_uart_exit(void) 1522 { 1523 printk(KERN_INFO 1524 "Freescale QUICC Engine UART device driver unloading\n"); 1525 1526 platform_driver_unregister(&ucc_uart_of_driver); 1527 uart_unregister_driver(&ucc_uart_driver); 1528 } 1529 1530 module_init(ucc_uart_init); 1531 module_exit(ucc_uart_exit); 1532 1533 MODULE_DESCRIPTION("Freescale QUICC Engine (QE) UART"); 1534 MODULE_AUTHOR("Timur Tabi <timur@freescale.com>"); 1535 MODULE_LICENSE("GPL v2"); 1536 MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_QE_MAJOR); 1537 1538