1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  *  Driver for CPM (SCC/SMC) serial ports; core driver
4  *
5  *  Based on arch/ppc/cpm2_io/uart.c by Dan Malek
6  *  Based on ppc8xx.c by Thomas Gleixner
7  *  Based on drivers/serial/amba.c by Russell King
8  *
9  *  Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
10  *              Pantelis Antoniou (panto@intracom.gr) (CPM1)
11  *
12  *  Copyright (C) 2004, 2007 Freescale Semiconductor, Inc.
13  *            (C) 2004 Intracom, S.A.
14  *            (C) 2005-2006 MontaVista Software, Inc.
15  *		Vitaly Bordug <vbordug@ru.mvista.com>
16  */
17 
18 #include <linux/module.h>
19 #include <linux/tty.h>
20 #include <linux/tty_flip.h>
21 #include <linux/ioport.h>
22 #include <linux/init.h>
23 #include <linux/serial.h>
24 #include <linux/console.h>
25 #include <linux/sysrq.h>
26 #include <linux/device.h>
27 #include <linux/memblock.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/fs_uart_pd.h>
30 #include <linux/of_address.h>
31 #include <linux/of_irq.h>
32 #include <linux/of_platform.h>
33 #include <linux/gpio/consumer.h>
34 #include <linux/clk.h>
35 
36 #include <asm/io.h>
37 #include <asm/irq.h>
38 #include <asm/delay.h>
39 #include <asm/fs_pd.h>
40 #include <asm/udbg.h>
41 
42 #include <linux/serial_core.h>
43 #include <linux/kernel.h>
44 
45 #include "cpm_uart.h"
46 
47 
48 /**************************************************************/
49 
50 static int  cpm_uart_tx_pump(struct uart_port *port);
51 static void cpm_uart_init_smc(struct uart_cpm_port *pinfo);
52 static void cpm_uart_init_scc(struct uart_cpm_port *pinfo);
53 static void cpm_uart_initbd(struct uart_cpm_port *pinfo);
54 
55 /**************************************************************/
56 
57 #define HW_BUF_SPD_THRESHOLD    2400
58 
59 /*
60  * Check, if transmit buffers are processed
61 */
cpm_uart_tx_empty(struct uart_port * port)62 static unsigned int cpm_uart_tx_empty(struct uart_port *port)
63 {
64 	struct uart_cpm_port *pinfo =
65 		container_of(port, struct uart_cpm_port, port);
66 	cbd_t __iomem *bdp = pinfo->tx_bd_base;
67 	int ret = 0;
68 
69 	while (1) {
70 		if (in_be16(&bdp->cbd_sc) & BD_SC_READY)
71 			break;
72 
73 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) {
74 			ret = TIOCSER_TEMT;
75 			break;
76 		}
77 		bdp++;
78 	}
79 
80 	pr_debug("CPM uart[%d]:tx_empty: %d\n", port->line, ret);
81 
82 	return ret;
83 }
84 
cpm_uart_set_mctrl(struct uart_port * port,unsigned int mctrl)85 static void cpm_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
86 {
87 	struct uart_cpm_port *pinfo =
88 		container_of(port, struct uart_cpm_port, port);
89 
90 	if (pinfo->gpios[GPIO_RTS])
91 		gpiod_set_value(pinfo->gpios[GPIO_RTS], !(mctrl & TIOCM_RTS));
92 
93 	if (pinfo->gpios[GPIO_DTR])
94 		gpiod_set_value(pinfo->gpios[GPIO_DTR], !(mctrl & TIOCM_DTR));
95 }
96 
cpm_uart_get_mctrl(struct uart_port * port)97 static unsigned int cpm_uart_get_mctrl(struct uart_port *port)
98 {
99 	struct uart_cpm_port *pinfo =
100 		container_of(port, struct uart_cpm_port, port);
101 	unsigned int mctrl = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
102 
103 	if (pinfo->gpios[GPIO_CTS]) {
104 		if (gpiod_get_value(pinfo->gpios[GPIO_CTS]))
105 			mctrl &= ~TIOCM_CTS;
106 	}
107 
108 	if (pinfo->gpios[GPIO_DSR]) {
109 		if (gpiod_get_value(pinfo->gpios[GPIO_DSR]))
110 			mctrl &= ~TIOCM_DSR;
111 	}
112 
113 	if (pinfo->gpios[GPIO_DCD]) {
114 		if (gpiod_get_value(pinfo->gpios[GPIO_DCD]))
115 			mctrl &= ~TIOCM_CAR;
116 	}
117 
118 	if (pinfo->gpios[GPIO_RI]) {
119 		if (!gpiod_get_value(pinfo->gpios[GPIO_RI]))
120 			mctrl |= TIOCM_RNG;
121 	}
122 
123 	return mctrl;
124 }
125 
126 /*
127  * Stop transmitter
128  */
cpm_uart_stop_tx(struct uart_port * port)129 static void cpm_uart_stop_tx(struct uart_port *port)
130 {
131 	struct uart_cpm_port *pinfo =
132 		container_of(port, struct uart_cpm_port, port);
133 	smc_t __iomem *smcp = pinfo->smcp;
134 	scc_t __iomem *sccp = pinfo->sccp;
135 
136 	pr_debug("CPM uart[%d]:stop tx\n", port->line);
137 
138 	if (IS_SMC(pinfo))
139 		clrbits8(&smcp->smc_smcm, SMCM_TX);
140 	else
141 		clrbits16(&sccp->scc_sccm, UART_SCCM_TX);
142 }
143 
144 /*
145  * Start transmitter
146  */
cpm_uart_start_tx(struct uart_port * port)147 static void cpm_uart_start_tx(struct uart_port *port)
148 {
149 	struct uart_cpm_port *pinfo =
150 		container_of(port, struct uart_cpm_port, port);
151 	smc_t __iomem *smcp = pinfo->smcp;
152 	scc_t __iomem *sccp = pinfo->sccp;
153 
154 	pr_debug("CPM uart[%d]:start tx\n", port->line);
155 
156 	if (IS_SMC(pinfo)) {
157 		if (in_8(&smcp->smc_smcm) & SMCM_TX)
158 			return;
159 	} else {
160 		if (in_be16(&sccp->scc_sccm) & UART_SCCM_TX)
161 			return;
162 	}
163 
164 	if (cpm_uart_tx_pump(port) != 0) {
165 		if (IS_SMC(pinfo)) {
166 			setbits8(&smcp->smc_smcm, SMCM_TX);
167 		} else {
168 			setbits16(&sccp->scc_sccm, UART_SCCM_TX);
169 		}
170 	}
171 }
172 
173 /*
174  * Stop receiver
175  */
cpm_uart_stop_rx(struct uart_port * port)176 static void cpm_uart_stop_rx(struct uart_port *port)
177 {
178 	struct uart_cpm_port *pinfo =
179 		container_of(port, struct uart_cpm_port, port);
180 	smc_t __iomem *smcp = pinfo->smcp;
181 	scc_t __iomem *sccp = pinfo->sccp;
182 
183 	pr_debug("CPM uart[%d]:stop rx\n", port->line);
184 
185 	if (IS_SMC(pinfo))
186 		clrbits8(&smcp->smc_smcm, SMCM_RX);
187 	else
188 		clrbits16(&sccp->scc_sccm, UART_SCCM_RX);
189 }
190 
191 /*
192  * Generate a break.
193  */
cpm_uart_break_ctl(struct uart_port * port,int break_state)194 static void cpm_uart_break_ctl(struct uart_port *port, int break_state)
195 {
196 	struct uart_cpm_port *pinfo =
197 		container_of(port, struct uart_cpm_port, port);
198 
199 	pr_debug("CPM uart[%d]:break ctrl, break_state: %d\n", port->line,
200 		break_state);
201 
202 	if (break_state)
203 		cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
204 	else
205 		cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX);
206 }
207 
208 /*
209  * Transmit characters, refill buffer descriptor, if possible
210  */
cpm_uart_int_tx(struct uart_port * port)211 static void cpm_uart_int_tx(struct uart_port *port)
212 {
213 	pr_debug("CPM uart[%d]:TX INT\n", port->line);
214 
215 	cpm_uart_tx_pump(port);
216 }
217 
218 #ifdef CONFIG_CONSOLE_POLL
219 static int serial_polled;
220 #endif
221 
222 /*
223  * Receive characters
224  */
cpm_uart_int_rx(struct uart_port * port)225 static void cpm_uart_int_rx(struct uart_port *port)
226 {
227 	int i;
228 	unsigned char ch;
229 	u8 *cp;
230 	struct tty_port *tport = &port->state->port;
231 	struct uart_cpm_port *pinfo =
232 		container_of(port, struct uart_cpm_port, port);
233 	cbd_t __iomem *bdp;
234 	u16 status;
235 	unsigned int flg;
236 
237 	pr_debug("CPM uart[%d]:RX INT\n", port->line);
238 
239 	/* Just loop through the closed BDs and copy the characters into
240 	 * the buffer.
241 	 */
242 	bdp = pinfo->rx_cur;
243 	for (;;) {
244 #ifdef CONFIG_CONSOLE_POLL
245 		if (unlikely(serial_polled)) {
246 			serial_polled = 0;
247 			return;
248 		}
249 #endif
250 		/* get status */
251 		status = in_be16(&bdp->cbd_sc);
252 		/* If this one is empty, return happy */
253 		if (status & BD_SC_EMPTY)
254 			break;
255 
256 		/* get number of characters, and check spce in flip-buffer */
257 		i = in_be16(&bdp->cbd_datlen);
258 
259 		/* If we have not enough room in tty flip buffer, then we try
260 		 * later, which will be the next rx-interrupt or a timeout
261 		 */
262 		if (tty_buffer_request_room(tport, i) < i) {
263 			printk(KERN_WARNING "No room in flip buffer\n");
264 			return;
265 		}
266 
267 		/* get pointer */
268 		cp = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
269 
270 		/* loop through the buffer */
271 		while (i-- > 0) {
272 			ch = *cp++;
273 			port->icount.rx++;
274 			flg = TTY_NORMAL;
275 
276 			if (status &
277 			    (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
278 				goto handle_error;
279 			if (uart_handle_sysrq_char(port, ch))
280 				continue;
281 #ifdef CONFIG_CONSOLE_POLL
282 			if (unlikely(serial_polled)) {
283 				serial_polled = 0;
284 				return;
285 			}
286 #endif
287 		      error_return:
288 			tty_insert_flip_char(tport, ch, flg);
289 
290 		}		/* End while (i--) */
291 
292 		/* This BD is ready to be used again. Clear status. get next */
293 		clrbits16(&bdp->cbd_sc, BD_SC_BR | BD_SC_FR | BD_SC_PR |
294 		                        BD_SC_OV | BD_SC_ID);
295 		setbits16(&bdp->cbd_sc, BD_SC_EMPTY);
296 
297 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
298 			bdp = pinfo->rx_bd_base;
299 		else
300 			bdp++;
301 
302 	} /* End for (;;) */
303 
304 	/* Write back buffer pointer */
305 	pinfo->rx_cur = bdp;
306 
307 	/* activate BH processing */
308 	tty_flip_buffer_push(tport);
309 
310 	return;
311 
312 	/* Error processing */
313 
314       handle_error:
315 	/* Statistics */
316 	if (status & BD_SC_BR)
317 		port->icount.brk++;
318 	if (status & BD_SC_PR)
319 		port->icount.parity++;
320 	if (status & BD_SC_FR)
321 		port->icount.frame++;
322 	if (status & BD_SC_OV)
323 		port->icount.overrun++;
324 
325 	/* Mask out ignored conditions */
326 	status &= port->read_status_mask;
327 
328 	/* Handle the remaining ones */
329 	if (status & BD_SC_BR)
330 		flg = TTY_BREAK;
331 	else if (status & BD_SC_PR)
332 		flg = TTY_PARITY;
333 	else if (status & BD_SC_FR)
334 		flg = TTY_FRAME;
335 
336 	/* overrun does not affect the current character ! */
337 	if (status & BD_SC_OV) {
338 		ch = 0;
339 		flg = TTY_OVERRUN;
340 		/* We skip this buffer */
341 		/* CHECK: Is really nothing senseful there */
342 		/* ASSUMPTION: it contains nothing valid */
343 		i = 0;
344 	}
345 	port->sysrq = 0;
346 	goto error_return;
347 }
348 
349 /*
350  * Asynchron mode interrupt handler
351  */
cpm_uart_int(int irq,void * data)352 static irqreturn_t cpm_uart_int(int irq, void *data)
353 {
354 	u8 events;
355 	struct uart_port *port = data;
356 	struct uart_cpm_port *pinfo = (struct uart_cpm_port *)port;
357 	smc_t __iomem *smcp = pinfo->smcp;
358 	scc_t __iomem *sccp = pinfo->sccp;
359 
360 	pr_debug("CPM uart[%d]:IRQ\n", port->line);
361 
362 	if (IS_SMC(pinfo)) {
363 		events = in_8(&smcp->smc_smce);
364 		out_8(&smcp->smc_smce, events);
365 		if (events & SMCM_BRKE)
366 			uart_handle_break(port);
367 		if (events & SMCM_RX)
368 			cpm_uart_int_rx(port);
369 		if (events & SMCM_TX)
370 			cpm_uart_int_tx(port);
371 	} else {
372 		events = in_be16(&sccp->scc_scce);
373 		out_be16(&sccp->scc_scce, events);
374 		if (events & UART_SCCM_BRKE)
375 			uart_handle_break(port);
376 		if (events & UART_SCCM_RX)
377 			cpm_uart_int_rx(port);
378 		if (events & UART_SCCM_TX)
379 			cpm_uart_int_tx(port);
380 	}
381 	return (events) ? IRQ_HANDLED : IRQ_NONE;
382 }
383 
cpm_uart_startup(struct uart_port * port)384 static int cpm_uart_startup(struct uart_port *port)
385 {
386 	int retval;
387 	struct uart_cpm_port *pinfo =
388 		container_of(port, struct uart_cpm_port, port);
389 
390 	pr_debug("CPM uart[%d]:startup\n", port->line);
391 
392 	/* If the port is not the console, make sure rx is disabled. */
393 	if (!(pinfo->flags & FLAG_CONSOLE)) {
394 		/* Disable UART rx */
395 		if (IS_SMC(pinfo)) {
396 			clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN);
397 			clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX);
398 		} else {
399 			clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR);
400 			clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
401 		}
402 		cpm_uart_initbd(pinfo);
403 		if (IS_SMC(pinfo)) {
404 			out_be32(&pinfo->smcup->smc_rstate, 0);
405 			out_be32(&pinfo->smcup->smc_tstate, 0);
406 			out_be16(&pinfo->smcup->smc_rbptr,
407 				 in_be16(&pinfo->smcup->smc_rbase));
408 			out_be16(&pinfo->smcup->smc_tbptr,
409 				 in_be16(&pinfo->smcup->smc_tbase));
410 		} else {
411 			cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
412 		}
413 	}
414 	/* Install interrupt handler. */
415 	retval = request_irq(port->irq, cpm_uart_int, 0, "cpm_uart", port);
416 	if (retval)
417 		return retval;
418 
419 	/* Startup rx-int */
420 	if (IS_SMC(pinfo)) {
421 		setbits8(&pinfo->smcp->smc_smcm, SMCM_RX);
422 		setbits16(&pinfo->smcp->smc_smcmr, (SMCMR_REN | SMCMR_TEN));
423 	} else {
424 		setbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
425 		setbits32(&pinfo->sccp->scc_gsmrl, (SCC_GSMRL_ENR | SCC_GSMRL_ENT));
426 	}
427 
428 	return 0;
429 }
430 
cpm_uart_wait_until_send(struct uart_cpm_port * pinfo)431 inline void cpm_uart_wait_until_send(struct uart_cpm_port *pinfo)
432 {
433 	set_current_state(TASK_UNINTERRUPTIBLE);
434 	schedule_timeout(pinfo->wait_closing);
435 }
436 
437 /*
438  * Shutdown the uart
439  */
cpm_uart_shutdown(struct uart_port * port)440 static void cpm_uart_shutdown(struct uart_port *port)
441 {
442 	struct uart_cpm_port *pinfo =
443 		container_of(port, struct uart_cpm_port, port);
444 
445 	pr_debug("CPM uart[%d]:shutdown\n", port->line);
446 
447 	/* free interrupt handler */
448 	free_irq(port->irq, port);
449 
450 	/* If the port is not the console, disable Rx and Tx. */
451 	if (!(pinfo->flags & FLAG_CONSOLE)) {
452 		/* Wait for all the BDs marked sent */
453 		while(!cpm_uart_tx_empty(port)) {
454 			set_current_state(TASK_UNINTERRUPTIBLE);
455 			schedule_timeout(2);
456 		}
457 
458 		if (pinfo->wait_closing)
459 			cpm_uart_wait_until_send(pinfo);
460 
461 		/* Stop uarts */
462 		if (IS_SMC(pinfo)) {
463 			smc_t __iomem *smcp = pinfo->smcp;
464 			clrbits16(&smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
465 			clrbits8(&smcp->smc_smcm, SMCM_RX | SMCM_TX);
466 		} else {
467 			scc_t __iomem *sccp = pinfo->sccp;
468 			clrbits32(&sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
469 			clrbits16(&sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
470 		}
471 
472 		/* Shut them really down and reinit buffer descriptors */
473 		if (IS_SMC(pinfo)) {
474 			out_be16(&pinfo->smcup->smc_brkcr, 0);
475 			cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
476 		} else {
477 			out_be16(&pinfo->sccup->scc_brkcr, 0);
478 			cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX);
479 		}
480 
481 		cpm_uart_initbd(pinfo);
482 	}
483 }
484 
cpm_uart_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)485 static void cpm_uart_set_termios(struct uart_port *port,
486                                  struct ktermios *termios,
487                                  struct ktermios *old)
488 {
489 	int baud;
490 	unsigned long flags;
491 	u16 cval, scval, prev_mode;
492 	int bits, sbits;
493 	struct uart_cpm_port *pinfo =
494 		container_of(port, struct uart_cpm_port, port);
495 	smc_t __iomem *smcp = pinfo->smcp;
496 	scc_t __iomem *sccp = pinfo->sccp;
497 	int maxidl;
498 
499 	pr_debug("CPM uart[%d]:set_termios\n", port->line);
500 
501 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
502 	if (baud < HW_BUF_SPD_THRESHOLD ||
503 	    (pinfo->port.state && pinfo->port.state->port.low_latency))
504 		pinfo->rx_fifosize = 1;
505 	else
506 		pinfo->rx_fifosize = RX_BUF_SIZE;
507 
508 	/* MAXIDL is the timeout after which a receive buffer is closed
509 	 * when not full if no more characters are received.
510 	 * We calculate it from the baudrate so that the duration is
511 	 * always the same at standard rates: about 4ms.
512 	 */
513 	maxidl = baud / 2400;
514 	if (maxidl < 1)
515 		maxidl = 1;
516 	if (maxidl > 0x10)
517 		maxidl = 0x10;
518 
519 	/* Character length programmed into the mode register is the
520 	 * sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
521 	 * 1 or 2 stop bits, minus 1.
522 	 * The value 'bits' counts this for us.
523 	 */
524 	cval = 0;
525 	scval = 0;
526 
527 	/* byte size */
528 	switch (termios->c_cflag & CSIZE) {
529 	case CS5:
530 		bits = 5;
531 		break;
532 	case CS6:
533 		bits = 6;
534 		break;
535 	case CS7:
536 		bits = 7;
537 		break;
538 	case CS8:
539 		bits = 8;
540 		break;
541 		/* Never happens, but GCC is too dumb to figure it out */
542 	default:
543 		bits = 8;
544 		break;
545 	}
546 	sbits = bits - 5;
547 
548 	if (termios->c_cflag & CSTOPB) {
549 		cval |= SMCMR_SL;	/* Two stops */
550 		scval |= SCU_PSMR_SL;
551 		bits++;
552 	}
553 
554 	if (termios->c_cflag & PARENB) {
555 		cval |= SMCMR_PEN;
556 		scval |= SCU_PSMR_PEN;
557 		bits++;
558 		if (!(termios->c_cflag & PARODD)) {
559 			cval |= SMCMR_PM_EVEN;
560 			scval |= (SCU_PSMR_REVP | SCU_PSMR_TEVP);
561 		}
562 	}
563 
564 	/*
565 	 * Update the timeout
566 	 */
567 	uart_update_timeout(port, termios->c_cflag, baud);
568 
569 	/*
570 	 * Set up parity check flag
571 	 */
572 	port->read_status_mask = (BD_SC_EMPTY | BD_SC_OV);
573 	if (termios->c_iflag & INPCK)
574 		port->read_status_mask |= BD_SC_FR | BD_SC_PR;
575 	if ((termios->c_iflag & BRKINT) || (termios->c_iflag & PARMRK))
576 		port->read_status_mask |= BD_SC_BR;
577 
578 	/*
579 	 * Characters to ignore
580 	 */
581 	port->ignore_status_mask = 0;
582 	if (termios->c_iflag & IGNPAR)
583 		port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
584 	if (termios->c_iflag & IGNBRK) {
585 		port->ignore_status_mask |= BD_SC_BR;
586 		/*
587 		 * If we're ignore parity and break indicators, ignore
588 		 * overruns too.  (For real raw support).
589 		 */
590 		if (termios->c_iflag & IGNPAR)
591 			port->ignore_status_mask |= BD_SC_OV;
592 	}
593 	/*
594 	 * !!! ignore all characters if CREAD is not set
595 	 */
596 	if ((termios->c_cflag & CREAD) == 0)
597 		port->read_status_mask &= ~BD_SC_EMPTY;
598 
599 	spin_lock_irqsave(&port->lock, flags);
600 
601 	/* Start bit has not been added (so don't, because we would just
602 	 * subtract it later), and we need to add one for the number of
603 	 * stops bits (there is always at least one).
604 	 */
605 	bits++;
606 	if (IS_SMC(pinfo)) {
607 		/*
608 		 * MRBLR can be changed while an SMC/SCC is operating only
609 		 * if it is done in a single bus cycle with one 16-bit move
610 		 * (not two 8-bit bus cycles back-to-back). This occurs when
611 		 * the cp shifts control to the next RxBD, so the change does
612 		 * not take effect immediately. To guarantee the exact RxBD
613 		 * on which the change occurs, change MRBLR only while the
614 		 * SMC/SCC receiver is disabled.
615 		 */
616 		out_be16(&pinfo->smcup->smc_mrblr, pinfo->rx_fifosize);
617 		out_be16(&pinfo->smcup->smc_maxidl, maxidl);
618 
619 		/* Set the mode register.  We want to keep a copy of the
620 		 * enables, because we want to put them back if they were
621 		 * present.
622 		 */
623 		prev_mode = in_be16(&smcp->smc_smcmr) & (SMCMR_REN | SMCMR_TEN);
624 		/* Output in *one* operation, so we don't interrupt RX/TX if they
625 		 * were already enabled. */
626 		out_be16(&smcp->smc_smcmr, smcr_mk_clen(bits) | cval |
627 		    SMCMR_SM_UART | prev_mode);
628 	} else {
629 		out_be16(&pinfo->sccup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
630 		out_be16(&pinfo->sccup->scc_maxidl, maxidl);
631 		out_be16(&sccp->scc_psmr, (sbits << 12) | scval);
632 	}
633 
634 	if (pinfo->clk)
635 		clk_set_rate(pinfo->clk, baud);
636 	else
637 		cpm_set_brg(pinfo->brg - 1, baud);
638 	spin_unlock_irqrestore(&port->lock, flags);
639 }
640 
cpm_uart_type(struct uart_port * port)641 static const char *cpm_uart_type(struct uart_port *port)
642 {
643 	pr_debug("CPM uart[%d]:uart_type\n", port->line);
644 
645 	return port->type == PORT_CPM ? "CPM UART" : NULL;
646 }
647 
648 /*
649  * verify the new serial_struct (for TIOCSSERIAL).
650  */
cpm_uart_verify_port(struct uart_port * port,struct serial_struct * ser)651 static int cpm_uart_verify_port(struct uart_port *port,
652 				struct serial_struct *ser)
653 {
654 	int ret = 0;
655 
656 	pr_debug("CPM uart[%d]:verify_port\n", port->line);
657 
658 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
659 		ret = -EINVAL;
660 	if (ser->irq < 0 || ser->irq >= nr_irqs)
661 		ret = -EINVAL;
662 	if (ser->baud_base < 9600)
663 		ret = -EINVAL;
664 	return ret;
665 }
666 
667 /*
668  * Transmit characters, refill buffer descriptor, if possible
669  */
cpm_uart_tx_pump(struct uart_port * port)670 static int cpm_uart_tx_pump(struct uart_port *port)
671 {
672 	cbd_t __iomem *bdp;
673 	u8 *p;
674 	int count;
675 	struct uart_cpm_port *pinfo =
676 		container_of(port, struct uart_cpm_port, port);
677 	struct circ_buf *xmit = &port->state->xmit;
678 
679 	/* Handle xon/xoff */
680 	if (port->x_char) {
681 		/* Pick next descriptor and fill from buffer */
682 		bdp = pinfo->tx_cur;
683 
684 		p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
685 
686 		*p++ = port->x_char;
687 
688 		out_be16(&bdp->cbd_datlen, 1);
689 		setbits16(&bdp->cbd_sc, BD_SC_READY);
690 		/* Get next BD. */
691 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
692 			bdp = pinfo->tx_bd_base;
693 		else
694 			bdp++;
695 		pinfo->tx_cur = bdp;
696 
697 		port->icount.tx++;
698 		port->x_char = 0;
699 		return 1;
700 	}
701 
702 	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
703 		cpm_uart_stop_tx(port);
704 		return 0;
705 	}
706 
707 	/* Pick next descriptor and fill from buffer */
708 	bdp = pinfo->tx_cur;
709 
710 	while (!(in_be16(&bdp->cbd_sc) & BD_SC_READY) &&
711 	       xmit->tail != xmit->head) {
712 		count = 0;
713 		p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
714 		while (count < pinfo->tx_fifosize) {
715 			*p++ = xmit->buf[xmit->tail];
716 			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
717 			port->icount.tx++;
718 			count++;
719 			if (xmit->head == xmit->tail)
720 				break;
721 		}
722 		out_be16(&bdp->cbd_datlen, count);
723 		setbits16(&bdp->cbd_sc, BD_SC_READY);
724 		/* Get next BD. */
725 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
726 			bdp = pinfo->tx_bd_base;
727 		else
728 			bdp++;
729 	}
730 	pinfo->tx_cur = bdp;
731 
732 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
733 		uart_write_wakeup(port);
734 
735 	if (uart_circ_empty(xmit)) {
736 		cpm_uart_stop_tx(port);
737 		return 0;
738 	}
739 
740 	return 1;
741 }
742 
743 /*
744  * init buffer descriptors
745  */
cpm_uart_initbd(struct uart_cpm_port * pinfo)746 static void cpm_uart_initbd(struct uart_cpm_port *pinfo)
747 {
748 	int i;
749 	u8 *mem_addr;
750 	cbd_t __iomem *bdp;
751 
752 	pr_debug("CPM uart[%d]:initbd\n", pinfo->port.line);
753 
754 	/* Set the physical address of the host memory
755 	 * buffers in the buffer descriptors, and the
756 	 * virtual address for us to work with.
757 	 */
758 	mem_addr = pinfo->mem_addr;
759 	bdp = pinfo->rx_cur = pinfo->rx_bd_base;
760 	for (i = 0; i < (pinfo->rx_nrfifos - 1); i++, bdp++) {
761 		out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
762 		out_be16(&bdp->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT);
763 		mem_addr += pinfo->rx_fifosize;
764 	}
765 
766 	out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
767 	out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
768 
769 	/* Set the physical address of the host memory
770 	 * buffers in the buffer descriptors, and the
771 	 * virtual address for us to work with.
772 	 */
773 	mem_addr = pinfo->mem_addr + L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize);
774 	bdp = pinfo->tx_cur = pinfo->tx_bd_base;
775 	for (i = 0; i < (pinfo->tx_nrfifos - 1); i++, bdp++) {
776 		out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
777 		out_be16(&bdp->cbd_sc, BD_SC_INTRPT);
778 		mem_addr += pinfo->tx_fifosize;
779 	}
780 
781 	out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
782 	out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_INTRPT);
783 }
784 
cpm_uart_init_scc(struct uart_cpm_port * pinfo)785 static void cpm_uart_init_scc(struct uart_cpm_port *pinfo)
786 {
787 	scc_t __iomem *scp;
788 	scc_uart_t __iomem *sup;
789 
790 	pr_debug("CPM uart[%d]:init_scc\n", pinfo->port.line);
791 
792 	scp = pinfo->sccp;
793 	sup = pinfo->sccup;
794 
795 	/* Store address */
796 	out_be16(&pinfo->sccup->scc_genscc.scc_rbase,
797 	         (u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE);
798 	out_be16(&pinfo->sccup->scc_genscc.scc_tbase,
799 	         (u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE);
800 
801 	/* Set up the uart parameters in the
802 	 * parameter ram.
803 	 */
804 
805 	cpm_set_scc_fcr(sup);
806 
807 	out_be16(&sup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
808 	out_be16(&sup->scc_maxidl, 0x10);
809 	out_be16(&sup->scc_brkcr, 1);
810 	out_be16(&sup->scc_parec, 0);
811 	out_be16(&sup->scc_frmec, 0);
812 	out_be16(&sup->scc_nosec, 0);
813 	out_be16(&sup->scc_brkec, 0);
814 	out_be16(&sup->scc_uaddr1, 0);
815 	out_be16(&sup->scc_uaddr2, 0);
816 	out_be16(&sup->scc_toseq, 0);
817 	out_be16(&sup->scc_char1, 0x8000);
818 	out_be16(&sup->scc_char2, 0x8000);
819 	out_be16(&sup->scc_char3, 0x8000);
820 	out_be16(&sup->scc_char4, 0x8000);
821 	out_be16(&sup->scc_char5, 0x8000);
822 	out_be16(&sup->scc_char6, 0x8000);
823 	out_be16(&sup->scc_char7, 0x8000);
824 	out_be16(&sup->scc_char8, 0x8000);
825 	out_be16(&sup->scc_rccm, 0xc0ff);
826 
827 	/* Send the CPM an initialize command.
828 	 */
829 	cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
830 
831 	/* Set UART mode, 8 bit, no parity, one stop.
832 	 * Enable receive and transmit.
833 	 */
834 	out_be32(&scp->scc_gsmrh, 0);
835 	out_be32(&scp->scc_gsmrl,
836 	         SCC_GSMRL_MODE_UART | SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16);
837 
838 	/* Enable rx interrupts  and clear all pending events.  */
839 	out_be16(&scp->scc_sccm, 0);
840 	out_be16(&scp->scc_scce, 0xffff);
841 	out_be16(&scp->scc_dsr, 0x7e7e);
842 	out_be16(&scp->scc_psmr, 0x3000);
843 
844 	setbits32(&scp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
845 }
846 
cpm_uart_init_smc(struct uart_cpm_port * pinfo)847 static void cpm_uart_init_smc(struct uart_cpm_port *pinfo)
848 {
849 	smc_t __iomem *sp;
850 	smc_uart_t __iomem *up;
851 
852 	pr_debug("CPM uart[%d]:init_smc\n", pinfo->port.line);
853 
854 	sp = pinfo->smcp;
855 	up = pinfo->smcup;
856 
857 	/* Store address */
858 	out_be16(&pinfo->smcup->smc_rbase,
859 	         (u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE);
860 	out_be16(&pinfo->smcup->smc_tbase,
861 	         (u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE);
862 
863 /*
864  *  In case SMC is being relocated...
865  */
866 	out_be16(&up->smc_rbptr, in_be16(&pinfo->smcup->smc_rbase));
867 	out_be16(&up->smc_tbptr, in_be16(&pinfo->smcup->smc_tbase));
868 	out_be32(&up->smc_rstate, 0);
869 	out_be32(&up->smc_tstate, 0);
870 	out_be16(&up->smc_brkcr, 1);              /* number of break chars */
871 	out_be16(&up->smc_brkec, 0);
872 
873 	/* Set up the uart parameters in the
874 	 * parameter ram.
875 	 */
876 	cpm_set_smc_fcr(up);
877 
878 	/* Using idle character time requires some additional tuning.  */
879 	out_be16(&up->smc_mrblr, pinfo->rx_fifosize);
880 	out_be16(&up->smc_maxidl, 0x10);
881 	out_be16(&up->smc_brklen, 0);
882 	out_be16(&up->smc_brkec, 0);
883 	out_be16(&up->smc_brkcr, 1);
884 
885 	/* Set UART mode, 8 bit, no parity, one stop.
886 	 * Enable receive and transmit.
887 	 */
888 	out_be16(&sp->smc_smcmr, smcr_mk_clen(9) | SMCMR_SM_UART);
889 
890 	/* Enable only rx interrupts clear all pending events. */
891 	out_8(&sp->smc_smcm, 0);
892 	out_8(&sp->smc_smce, 0xff);
893 
894 	setbits16(&sp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
895 }
896 
897 /*
898  * Initialize port. This is called from early_console stuff
899  * so we have to be careful here !
900  */
cpm_uart_request_port(struct uart_port * port)901 static int cpm_uart_request_port(struct uart_port *port)
902 {
903 	struct uart_cpm_port *pinfo =
904 		container_of(port, struct uart_cpm_port, port);
905 	int ret;
906 
907 	pr_debug("CPM uart[%d]:request port\n", port->line);
908 
909 	if (pinfo->flags & FLAG_CONSOLE)
910 		return 0;
911 
912 	if (IS_SMC(pinfo)) {
913 		clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX);
914 		clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
915 	} else {
916 		clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
917 		clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
918 	}
919 
920 	ret = cpm_uart_allocbuf(pinfo, 0);
921 
922 	if (ret)
923 		return ret;
924 
925 	cpm_uart_initbd(pinfo);
926 	if (IS_SMC(pinfo))
927 		cpm_uart_init_smc(pinfo);
928 	else
929 		cpm_uart_init_scc(pinfo);
930 
931 	return 0;
932 }
933 
cpm_uart_release_port(struct uart_port * port)934 static void cpm_uart_release_port(struct uart_port *port)
935 {
936 	struct uart_cpm_port *pinfo =
937 		container_of(port, struct uart_cpm_port, port);
938 
939 	if (!(pinfo->flags & FLAG_CONSOLE))
940 		cpm_uart_freebuf(pinfo);
941 }
942 
943 /*
944  * Configure/autoconfigure the port.
945  */
cpm_uart_config_port(struct uart_port * port,int flags)946 static void cpm_uart_config_port(struct uart_port *port, int flags)
947 {
948 	pr_debug("CPM uart[%d]:config_port\n", port->line);
949 
950 	if (flags & UART_CONFIG_TYPE) {
951 		port->type = PORT_CPM;
952 		cpm_uart_request_port(port);
953 	}
954 }
955 
956 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_CPM_CONSOLE)
957 /*
958  * Write a string to the serial port
959  * Note that this is called with interrupts already disabled
960  */
cpm_uart_early_write(struct uart_cpm_port * pinfo,const char * string,u_int count,bool handle_linefeed)961 static void cpm_uart_early_write(struct uart_cpm_port *pinfo,
962 		const char *string, u_int count, bool handle_linefeed)
963 {
964 	unsigned int i;
965 	cbd_t __iomem *bdp, *bdbase;
966 	unsigned char *cpm_outp_addr;
967 
968 	/* Get the address of the host memory buffer.
969 	 */
970 	bdp = pinfo->tx_cur;
971 	bdbase = pinfo->tx_bd_base;
972 
973 	/*
974 	 * Now, do each character.  This is not as bad as it looks
975 	 * since this is a holding FIFO and not a transmitting FIFO.
976 	 * We could add the complexity of filling the entire transmit
977 	 * buffer, but we would just wait longer between accesses......
978 	 */
979 	for (i = 0; i < count; i++, string++) {
980 		/* Wait for transmitter fifo to empty.
981 		 * Ready indicates output is ready, and xmt is doing
982 		 * that, not that it is ready for us to send.
983 		 */
984 		while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
985 			;
986 
987 		/* Send the character out.
988 		 * If the buffer address is in the CPM DPRAM, don't
989 		 * convert it.
990 		 */
991 		cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr),
992 					pinfo);
993 		*cpm_outp_addr = *string;
994 
995 		out_be16(&bdp->cbd_datlen, 1);
996 		setbits16(&bdp->cbd_sc, BD_SC_READY);
997 
998 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
999 			bdp = bdbase;
1000 		else
1001 			bdp++;
1002 
1003 		/* if a LF, also do CR... */
1004 		if (handle_linefeed && *string == 10) {
1005 			while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
1006 				;
1007 
1008 			cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr),
1009 						pinfo);
1010 			*cpm_outp_addr = 13;
1011 
1012 			out_be16(&bdp->cbd_datlen, 1);
1013 			setbits16(&bdp->cbd_sc, BD_SC_READY);
1014 
1015 			if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
1016 				bdp = bdbase;
1017 			else
1018 				bdp++;
1019 		}
1020 	}
1021 
1022 	/*
1023 	 * Finally, Wait for transmitter & holding register to empty
1024 	 *  and restore the IER
1025 	 */
1026 	while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
1027 		;
1028 
1029 	pinfo->tx_cur = bdp;
1030 }
1031 #endif
1032 
1033 #ifdef CONFIG_CONSOLE_POLL
1034 /* Serial polling routines for writing and reading from the uart while
1035  * in an interrupt or debug context.
1036  */
1037 
1038 #define GDB_BUF_SIZE	512	/* power of 2, please */
1039 
1040 static char poll_buf[GDB_BUF_SIZE];
1041 static char *pollp;
1042 static int poll_chars;
1043 
poll_wait_key(char * obuf,struct uart_cpm_port * pinfo)1044 static int poll_wait_key(char *obuf, struct uart_cpm_port *pinfo)
1045 {
1046 	u_char		c, *cp;
1047 	volatile cbd_t	*bdp;
1048 	int		i;
1049 
1050 	/* Get the address of the host memory buffer.
1051 	 */
1052 	bdp = pinfo->rx_cur;
1053 	if (bdp->cbd_sc & BD_SC_EMPTY)
1054 		return NO_POLL_CHAR;
1055 
1056 	/* If the buffer address is in the CPM DPRAM, don't
1057 	 * convert it.
1058 	 */
1059 	cp = cpm2cpu_addr(bdp->cbd_bufaddr, pinfo);
1060 
1061 	if (obuf) {
1062 		i = c = bdp->cbd_datlen;
1063 		while (i-- > 0)
1064 			*obuf++ = *cp++;
1065 	} else
1066 		c = *cp;
1067 	bdp->cbd_sc &= ~(BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV | BD_SC_ID);
1068 	bdp->cbd_sc |= BD_SC_EMPTY;
1069 
1070 	if (bdp->cbd_sc & BD_SC_WRAP)
1071 		bdp = pinfo->rx_bd_base;
1072 	else
1073 		bdp++;
1074 	pinfo->rx_cur = (cbd_t *)bdp;
1075 
1076 	return (int)c;
1077 }
1078 
cpm_get_poll_char(struct uart_port * port)1079 static int cpm_get_poll_char(struct uart_port *port)
1080 {
1081 	struct uart_cpm_port *pinfo =
1082 		container_of(port, struct uart_cpm_port, port);
1083 
1084 	if (!serial_polled) {
1085 		serial_polled = 1;
1086 		poll_chars = 0;
1087 	}
1088 	if (poll_chars <= 0) {
1089 		int ret = poll_wait_key(poll_buf, pinfo);
1090 
1091 		if (ret == NO_POLL_CHAR)
1092 			return ret;
1093 		poll_chars = ret;
1094 		pollp = poll_buf;
1095 	}
1096 	poll_chars--;
1097 	return *pollp++;
1098 }
1099 
cpm_put_poll_char(struct uart_port * port,unsigned char c)1100 static void cpm_put_poll_char(struct uart_port *port,
1101 			 unsigned char c)
1102 {
1103 	struct uart_cpm_port *pinfo =
1104 		container_of(port, struct uart_cpm_port, port);
1105 	static char ch[2];
1106 
1107 	ch[0] = (char)c;
1108 	cpm_uart_early_write(pinfo, ch, 1, false);
1109 }
1110 #endif /* CONFIG_CONSOLE_POLL */
1111 
1112 static const struct uart_ops cpm_uart_pops = {
1113 	.tx_empty	= cpm_uart_tx_empty,
1114 	.set_mctrl	= cpm_uart_set_mctrl,
1115 	.get_mctrl	= cpm_uart_get_mctrl,
1116 	.stop_tx	= cpm_uart_stop_tx,
1117 	.start_tx	= cpm_uart_start_tx,
1118 	.stop_rx	= cpm_uart_stop_rx,
1119 	.break_ctl	= cpm_uart_break_ctl,
1120 	.startup	= cpm_uart_startup,
1121 	.shutdown	= cpm_uart_shutdown,
1122 	.set_termios	= cpm_uart_set_termios,
1123 	.type		= cpm_uart_type,
1124 	.release_port	= cpm_uart_release_port,
1125 	.request_port	= cpm_uart_request_port,
1126 	.config_port	= cpm_uart_config_port,
1127 	.verify_port	= cpm_uart_verify_port,
1128 #ifdef CONFIG_CONSOLE_POLL
1129 	.poll_get_char = cpm_get_poll_char,
1130 	.poll_put_char = cpm_put_poll_char,
1131 #endif
1132 };
1133 
1134 struct uart_cpm_port cpm_uart_ports[UART_NR];
1135 
cpm_uart_init_port(struct device_node * np,struct uart_cpm_port * pinfo)1136 static int cpm_uart_init_port(struct device_node *np,
1137                               struct uart_cpm_port *pinfo)
1138 {
1139 	const u32 *data;
1140 	void __iomem *mem, *pram;
1141 	struct device *dev = pinfo->port.dev;
1142 	int len;
1143 	int ret;
1144 	int i;
1145 
1146 	data = of_get_property(np, "clock", NULL);
1147 	if (data) {
1148 		struct clk *clk = clk_get(NULL, (const char*)data);
1149 		if (!IS_ERR(clk))
1150 			pinfo->clk = clk;
1151 	}
1152 	if (!pinfo->clk) {
1153 		data = of_get_property(np, "fsl,cpm-brg", &len);
1154 		if (!data || len != 4) {
1155 			printk(KERN_ERR "CPM UART %pOFn has no/invalid "
1156 			                "fsl,cpm-brg property.\n", np);
1157 			return -EINVAL;
1158 		}
1159 		pinfo->brg = *data;
1160 	}
1161 
1162 	data = of_get_property(np, "fsl,cpm-command", &len);
1163 	if (!data || len != 4) {
1164 		printk(KERN_ERR "CPM UART %pOFn has no/invalid "
1165 		                "fsl,cpm-command property.\n", np);
1166 		return -EINVAL;
1167 	}
1168 	pinfo->command = *data;
1169 
1170 	mem = of_iomap(np, 0);
1171 	if (!mem)
1172 		return -ENOMEM;
1173 
1174 	if (of_device_is_compatible(np, "fsl,cpm1-scc-uart") ||
1175 	    of_device_is_compatible(np, "fsl,cpm2-scc-uart")) {
1176 		pinfo->sccp = mem;
1177 		pinfo->sccup = pram = cpm_uart_map_pram(pinfo, np);
1178 	} else if (of_device_is_compatible(np, "fsl,cpm1-smc-uart") ||
1179 	           of_device_is_compatible(np, "fsl,cpm2-smc-uart")) {
1180 		pinfo->flags |= FLAG_SMC;
1181 		pinfo->smcp = mem;
1182 		pinfo->smcup = pram = cpm_uart_map_pram(pinfo, np);
1183 	} else {
1184 		ret = -ENODEV;
1185 		goto out_mem;
1186 	}
1187 
1188 	if (!pram) {
1189 		ret = -ENOMEM;
1190 		goto out_mem;
1191 	}
1192 
1193 	pinfo->tx_nrfifos = TX_NUM_FIFO;
1194 	pinfo->tx_fifosize = TX_BUF_SIZE;
1195 	pinfo->rx_nrfifos = RX_NUM_FIFO;
1196 	pinfo->rx_fifosize = RX_BUF_SIZE;
1197 
1198 	pinfo->port.uartclk = ppc_proc_freq;
1199 	pinfo->port.mapbase = (unsigned long)mem;
1200 	pinfo->port.type = PORT_CPM;
1201 	pinfo->port.ops = &cpm_uart_pops;
1202 	pinfo->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_CPM_CONSOLE);
1203 	pinfo->port.iotype = UPIO_MEM;
1204 	pinfo->port.fifosize = pinfo->tx_nrfifos * pinfo->tx_fifosize;
1205 	spin_lock_init(&pinfo->port.lock);
1206 
1207 	pinfo->port.irq = irq_of_parse_and_map(np, 0);
1208 	if (pinfo->port.irq == NO_IRQ) {
1209 		ret = -EINVAL;
1210 		goto out_pram;
1211 	}
1212 
1213 	for (i = 0; i < NUM_GPIOS; i++) {
1214 		struct gpio_desc *gpiod;
1215 
1216 		pinfo->gpios[i] = NULL;
1217 
1218 		gpiod = devm_gpiod_get_index_optional(dev, NULL, i, GPIOD_ASIS);
1219 
1220 		if (IS_ERR(gpiod)) {
1221 			ret = PTR_ERR(gpiod);
1222 			goto out_irq;
1223 		}
1224 
1225 		if (gpiod) {
1226 			if (i == GPIO_RTS || i == GPIO_DTR)
1227 				ret = gpiod_direction_output(gpiod, 0);
1228 			else
1229 				ret = gpiod_direction_input(gpiod);
1230 			if (ret) {
1231 				pr_err("can't set direction for gpio #%d: %d\n",
1232 					i, ret);
1233 				continue;
1234 			}
1235 			pinfo->gpios[i] = gpiod;
1236 		}
1237 	}
1238 
1239 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
1240 	udbg_putc = NULL;
1241 #endif
1242 
1243 	return cpm_uart_request_port(&pinfo->port);
1244 
1245 out_irq:
1246 	irq_dispose_mapping(pinfo->port.irq);
1247 out_pram:
1248 	cpm_uart_unmap_pram(pinfo, pram);
1249 out_mem:
1250 	iounmap(mem);
1251 	return ret;
1252 }
1253 
1254 #ifdef CONFIG_SERIAL_CPM_CONSOLE
1255 /*
1256  *	Print a string to the serial port trying not to disturb
1257  *	any possible real use of the port...
1258  *
1259  *	Note that this is called with interrupts already disabled
1260  */
cpm_uart_console_write(struct console * co,const char * s,u_int count)1261 static void cpm_uart_console_write(struct console *co, const char *s,
1262 				   u_int count)
1263 {
1264 	struct uart_cpm_port *pinfo = &cpm_uart_ports[co->index];
1265 	unsigned long flags;
1266 	int nolock = oops_in_progress;
1267 
1268 	if (unlikely(nolock)) {
1269 		local_irq_save(flags);
1270 	} else {
1271 		spin_lock_irqsave(&pinfo->port.lock, flags);
1272 	}
1273 
1274 	cpm_uart_early_write(pinfo, s, count, true);
1275 
1276 	if (unlikely(nolock)) {
1277 		local_irq_restore(flags);
1278 	} else {
1279 		spin_unlock_irqrestore(&pinfo->port.lock, flags);
1280 	}
1281 }
1282 
1283 
cpm_uart_console_setup(struct console * co,char * options)1284 static int __init cpm_uart_console_setup(struct console *co, char *options)
1285 {
1286 	int baud = 38400;
1287 	int bits = 8;
1288 	int parity = 'n';
1289 	int flow = 'n';
1290 	int ret;
1291 	struct uart_cpm_port *pinfo;
1292 	struct uart_port *port;
1293 
1294 	struct device_node *np;
1295 	int i = 0;
1296 
1297 	if (co->index >= UART_NR) {
1298 		printk(KERN_ERR "cpm_uart: console index %d too high\n",
1299 		       co->index);
1300 		return -ENODEV;
1301 	}
1302 
1303 	for_each_node_by_type(np, "serial") {
1304 		if (!of_device_is_compatible(np, "fsl,cpm1-smc-uart") &&
1305 		    !of_device_is_compatible(np, "fsl,cpm1-scc-uart") &&
1306 		    !of_device_is_compatible(np, "fsl,cpm2-smc-uart") &&
1307 		    !of_device_is_compatible(np, "fsl,cpm2-scc-uart"))
1308 			continue;
1309 
1310 		if (i++ == co->index)
1311 			break;
1312 	}
1313 
1314 	if (!np)
1315 		return -ENODEV;
1316 
1317 	pinfo = &cpm_uart_ports[co->index];
1318 
1319 	pinfo->flags |= FLAG_CONSOLE;
1320 	port = &pinfo->port;
1321 
1322 	ret = cpm_uart_init_port(np, pinfo);
1323 	of_node_put(np);
1324 	if (ret)
1325 		return ret;
1326 
1327 	if (options) {
1328 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1329 	} else {
1330 		if ((baud = uart_baudrate()) == -1)
1331 			baud = 9600;
1332 	}
1333 
1334 	if (IS_SMC(pinfo)) {
1335 		out_be16(&pinfo->smcup->smc_brkcr, 0);
1336 		cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
1337 		clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX);
1338 		clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
1339 	} else {
1340 		out_be16(&pinfo->sccup->scc_brkcr, 0);
1341 		cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX);
1342 		clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
1343 		clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
1344 	}
1345 
1346 	ret = cpm_uart_allocbuf(pinfo, 1);
1347 
1348 	if (ret)
1349 		return ret;
1350 
1351 	cpm_uart_initbd(pinfo);
1352 
1353 	if (IS_SMC(pinfo))
1354 		cpm_uart_init_smc(pinfo);
1355 	else
1356 		cpm_uart_init_scc(pinfo);
1357 
1358 	uart_set_options(port, co, baud, parity, bits, flow);
1359 	cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX);
1360 
1361 	return 0;
1362 }
1363 
1364 static struct uart_driver cpm_reg;
1365 static struct console cpm_scc_uart_console = {
1366 	.name		= "ttyCPM",
1367 	.write		= cpm_uart_console_write,
1368 	.device		= uart_console_device,
1369 	.setup		= cpm_uart_console_setup,
1370 	.flags		= CON_PRINTBUFFER,
1371 	.index		= -1,
1372 	.data		= &cpm_reg,
1373 };
1374 
cpm_uart_console_init(void)1375 static int __init cpm_uart_console_init(void)
1376 {
1377 	cpm_muram_init();
1378 	register_console(&cpm_scc_uart_console);
1379 	return 0;
1380 }
1381 
1382 console_initcall(cpm_uart_console_init);
1383 
1384 #define CPM_UART_CONSOLE	&cpm_scc_uart_console
1385 #else
1386 #define CPM_UART_CONSOLE	NULL
1387 #endif
1388 
1389 static struct uart_driver cpm_reg = {
1390 	.owner		= THIS_MODULE,
1391 	.driver_name	= "ttyCPM",
1392 	.dev_name	= "ttyCPM",
1393 	.major		= SERIAL_CPM_MAJOR,
1394 	.minor		= SERIAL_CPM_MINOR,
1395 	.cons		= CPM_UART_CONSOLE,
1396 	.nr		= UART_NR,
1397 };
1398 
1399 static int probe_index;
1400 
cpm_uart_probe(struct platform_device * ofdev)1401 static int cpm_uart_probe(struct platform_device *ofdev)
1402 {
1403 	int index = probe_index++;
1404 	struct uart_cpm_port *pinfo = &cpm_uart_ports[index];
1405 	int ret;
1406 
1407 	pinfo->port.line = index;
1408 
1409 	if (index >= UART_NR)
1410 		return -ENODEV;
1411 
1412 	platform_set_drvdata(ofdev, pinfo);
1413 
1414 	/* initialize the device pointer for the port */
1415 	pinfo->port.dev = &ofdev->dev;
1416 
1417 	ret = cpm_uart_init_port(ofdev->dev.of_node, pinfo);
1418 	if (ret)
1419 		return ret;
1420 
1421 	return uart_add_one_port(&cpm_reg, &pinfo->port);
1422 }
1423 
cpm_uart_remove(struct platform_device * ofdev)1424 static int cpm_uart_remove(struct platform_device *ofdev)
1425 {
1426 	struct uart_cpm_port *pinfo = platform_get_drvdata(ofdev);
1427 	return uart_remove_one_port(&cpm_reg, &pinfo->port);
1428 }
1429 
1430 static const struct of_device_id cpm_uart_match[] = {
1431 	{
1432 		.compatible = "fsl,cpm1-smc-uart",
1433 	},
1434 	{
1435 		.compatible = "fsl,cpm1-scc-uart",
1436 	},
1437 	{
1438 		.compatible = "fsl,cpm2-smc-uart",
1439 	},
1440 	{
1441 		.compatible = "fsl,cpm2-scc-uart",
1442 	},
1443 	{}
1444 };
1445 MODULE_DEVICE_TABLE(of, cpm_uart_match);
1446 
1447 static struct platform_driver cpm_uart_driver = {
1448 	.driver = {
1449 		.name = "cpm_uart",
1450 		.of_match_table = cpm_uart_match,
1451 	},
1452 	.probe = cpm_uart_probe,
1453 	.remove = cpm_uart_remove,
1454  };
1455 
cpm_uart_init(void)1456 static int __init cpm_uart_init(void)
1457 {
1458 	int ret = uart_register_driver(&cpm_reg);
1459 	if (ret)
1460 		return ret;
1461 
1462 	ret = platform_driver_register(&cpm_uart_driver);
1463 	if (ret)
1464 		uart_unregister_driver(&cpm_reg);
1465 
1466 	return ret;
1467 }
1468 
cpm_uart_exit(void)1469 static void __exit cpm_uart_exit(void)
1470 {
1471 	platform_driver_unregister(&cpm_uart_driver);
1472 	uart_unregister_driver(&cpm_reg);
1473 }
1474 
1475 module_init(cpm_uart_init);
1476 module_exit(cpm_uart_exit);
1477 
1478 MODULE_AUTHOR("Kumar Gala/Antoniou Pantelis");
1479 MODULE_DESCRIPTION("CPM SCC/SMC port driver $Revision: 0.01 $");
1480 MODULE_LICENSE("GPL");
1481 MODULE_ALIAS_CHARDEV(SERIAL_CPM_MAJOR, SERIAL_CPM_MINOR);
1482