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1 /*
2  *  Driver for CPM (SCC/SMC) serial ports; core driver
3  *
4  *  Based on arch/ppc/cpm2_io/uart.c by Dan Malek
5  *  Based on ppc8xx.c by Thomas Gleixner
6  *  Based on drivers/serial/amba.c by Russell King
7  *
8  *  Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
9  *              Pantelis Antoniou (panto@intracom.gr) (CPM1)
10  *
11  *  Copyright (C) 2004, 2007 Freescale Semiconductor, Inc.
12  *            (C) 2004 Intracom, S.A.
13  *            (C) 2005-2006 MontaVista Software, Inc.
14  *		Vitaly Bordug <vbordug@ru.mvista.com>
15  *
16  * This program is free software; you can redistribute it and/or modify
17  * it under the terms of the GNU General Public License as published by
18  * the Free Software Foundation; either version 2 of the License, or
19  * (at your option) any later version.
20  *
21  * This program is distributed in the hope that it will be useful,
22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24  * GNU General Public License for more details.
25  *
26  * You should have received a copy of the GNU General Public License
27  * along with this program; if not, write to the Free Software
28  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
29  *
30  */
31 
32 #include <linux/module.h>
33 #include <linux/tty.h>
34 #include <linux/tty_flip.h>
35 #include <linux/ioport.h>
36 #include <linux/init.h>
37 #include <linux/serial.h>
38 #include <linux/console.h>
39 #include <linux/sysrq.h>
40 #include <linux/device.h>
41 #include <linux/bootmem.h>
42 #include <linux/dma-mapping.h>
43 #include <linux/fs_uart_pd.h>
44 #include <linux/of_address.h>
45 #include <linux/of_irq.h>
46 #include <linux/of_platform.h>
47 #include <linux/gpio.h>
48 #include <linux/of_gpio.h>
49 #include <linux/clk.h>
50 
51 #include <asm/io.h>
52 #include <asm/irq.h>
53 #include <asm/delay.h>
54 #include <asm/fs_pd.h>
55 #include <asm/udbg.h>
56 
57 #if defined(CONFIG_SERIAL_CPM_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
58 #define SUPPORT_SYSRQ
59 #endif
60 
61 #include <linux/serial_core.h>
62 #include <linux/kernel.h>
63 
64 #include "cpm_uart.h"
65 
66 
67 /**************************************************************/
68 
69 static int  cpm_uart_tx_pump(struct uart_port *port);
70 static void cpm_uart_init_smc(struct uart_cpm_port *pinfo);
71 static void cpm_uart_init_scc(struct uart_cpm_port *pinfo);
72 static void cpm_uart_initbd(struct uart_cpm_port *pinfo);
73 
74 /**************************************************************/
75 
76 #define HW_BUF_SPD_THRESHOLD    2400
77 
78 /*
79  * Check, if transmit buffers are processed
80 */
cpm_uart_tx_empty(struct uart_port * port)81 static unsigned int cpm_uart_tx_empty(struct uart_port *port)
82 {
83 	struct uart_cpm_port *pinfo =
84 		container_of(port, struct uart_cpm_port, port);
85 	cbd_t __iomem *bdp = pinfo->tx_bd_base;
86 	int ret = 0;
87 
88 	while (1) {
89 		if (in_be16(&bdp->cbd_sc) & BD_SC_READY)
90 			break;
91 
92 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) {
93 			ret = TIOCSER_TEMT;
94 			break;
95 		}
96 		bdp++;
97 	}
98 
99 	pr_debug("CPM uart[%d]:tx_empty: %d\n", port->line, ret);
100 
101 	return ret;
102 }
103 
cpm_uart_set_mctrl(struct uart_port * port,unsigned int mctrl)104 static void cpm_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
105 {
106 	struct uart_cpm_port *pinfo =
107 		container_of(port, struct uart_cpm_port, port);
108 
109 	if (pinfo->gpios[GPIO_RTS] >= 0)
110 		gpio_set_value(pinfo->gpios[GPIO_RTS], !(mctrl & TIOCM_RTS));
111 
112 	if (pinfo->gpios[GPIO_DTR] >= 0)
113 		gpio_set_value(pinfo->gpios[GPIO_DTR], !(mctrl & TIOCM_DTR));
114 }
115 
cpm_uart_get_mctrl(struct uart_port * port)116 static unsigned int cpm_uart_get_mctrl(struct uart_port *port)
117 {
118 	struct uart_cpm_port *pinfo =
119 		container_of(port, struct uart_cpm_port, port);
120 	unsigned int mctrl = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
121 
122 	if (pinfo->gpios[GPIO_CTS] >= 0) {
123 		if (gpio_get_value(pinfo->gpios[GPIO_CTS]))
124 			mctrl &= ~TIOCM_CTS;
125 	}
126 
127 	if (pinfo->gpios[GPIO_DSR] >= 0) {
128 		if (gpio_get_value(pinfo->gpios[GPIO_DSR]))
129 			mctrl &= ~TIOCM_DSR;
130 	}
131 
132 	if (pinfo->gpios[GPIO_DCD] >= 0) {
133 		if (gpio_get_value(pinfo->gpios[GPIO_DCD]))
134 			mctrl &= ~TIOCM_CAR;
135 	}
136 
137 	if (pinfo->gpios[GPIO_RI] >= 0) {
138 		if (!gpio_get_value(pinfo->gpios[GPIO_RI]))
139 			mctrl |= TIOCM_RNG;
140 	}
141 
142 	return mctrl;
143 }
144 
145 /*
146  * Stop transmitter
147  */
cpm_uart_stop_tx(struct uart_port * port)148 static void cpm_uart_stop_tx(struct uart_port *port)
149 {
150 	struct uart_cpm_port *pinfo =
151 		container_of(port, struct uart_cpm_port, port);
152 	smc_t __iomem *smcp = pinfo->smcp;
153 	scc_t __iomem *sccp = pinfo->sccp;
154 
155 	pr_debug("CPM uart[%d]:stop tx\n", port->line);
156 
157 	if (IS_SMC(pinfo))
158 		clrbits8(&smcp->smc_smcm, SMCM_TX);
159 	else
160 		clrbits16(&sccp->scc_sccm, UART_SCCM_TX);
161 }
162 
163 /*
164  * Start transmitter
165  */
cpm_uart_start_tx(struct uart_port * port)166 static void cpm_uart_start_tx(struct uart_port *port)
167 {
168 	struct uart_cpm_port *pinfo =
169 		container_of(port, struct uart_cpm_port, port);
170 	smc_t __iomem *smcp = pinfo->smcp;
171 	scc_t __iomem *sccp = pinfo->sccp;
172 
173 	pr_debug("CPM uart[%d]:start tx\n", port->line);
174 
175 	if (IS_SMC(pinfo)) {
176 		if (in_8(&smcp->smc_smcm) & SMCM_TX)
177 			return;
178 	} else {
179 		if (in_be16(&sccp->scc_sccm) & UART_SCCM_TX)
180 			return;
181 	}
182 
183 	if (cpm_uart_tx_pump(port) != 0) {
184 		if (IS_SMC(pinfo)) {
185 			setbits8(&smcp->smc_smcm, SMCM_TX);
186 		} else {
187 			setbits16(&sccp->scc_sccm, UART_SCCM_TX);
188 		}
189 	}
190 }
191 
192 /*
193  * Stop receiver
194  */
cpm_uart_stop_rx(struct uart_port * port)195 static void cpm_uart_stop_rx(struct uart_port *port)
196 {
197 	struct uart_cpm_port *pinfo =
198 		container_of(port, struct uart_cpm_port, port);
199 	smc_t __iomem *smcp = pinfo->smcp;
200 	scc_t __iomem *sccp = pinfo->sccp;
201 
202 	pr_debug("CPM uart[%d]:stop rx\n", port->line);
203 
204 	if (IS_SMC(pinfo))
205 		clrbits8(&smcp->smc_smcm, SMCM_RX);
206 	else
207 		clrbits16(&sccp->scc_sccm, UART_SCCM_RX);
208 }
209 
210 /*
211  * Generate a break.
212  */
cpm_uart_break_ctl(struct uart_port * port,int break_state)213 static void cpm_uart_break_ctl(struct uart_port *port, int break_state)
214 {
215 	struct uart_cpm_port *pinfo =
216 		container_of(port, struct uart_cpm_port, port);
217 
218 	pr_debug("CPM uart[%d]:break ctrl, break_state: %d\n", port->line,
219 		break_state);
220 
221 	if (break_state)
222 		cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
223 	else
224 		cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX);
225 }
226 
227 /*
228  * Transmit characters, refill buffer descriptor, if possible
229  */
cpm_uart_int_tx(struct uart_port * port)230 static void cpm_uart_int_tx(struct uart_port *port)
231 {
232 	pr_debug("CPM uart[%d]:TX INT\n", port->line);
233 
234 	cpm_uart_tx_pump(port);
235 }
236 
237 #ifdef CONFIG_CONSOLE_POLL
238 static int serial_polled;
239 #endif
240 
241 /*
242  * Receive characters
243  */
cpm_uart_int_rx(struct uart_port * port)244 static void cpm_uart_int_rx(struct uart_port *port)
245 {
246 	int i;
247 	unsigned char ch;
248 	u8 *cp;
249 	struct tty_port *tport = &port->state->port;
250 	struct uart_cpm_port *pinfo =
251 		container_of(port, struct uart_cpm_port, port);
252 	cbd_t __iomem *bdp;
253 	u16 status;
254 	unsigned int flg;
255 
256 	pr_debug("CPM uart[%d]:RX INT\n", port->line);
257 
258 	/* Just loop through the closed BDs and copy the characters into
259 	 * the buffer.
260 	 */
261 	bdp = pinfo->rx_cur;
262 	for (;;) {
263 #ifdef CONFIG_CONSOLE_POLL
264 		if (unlikely(serial_polled)) {
265 			serial_polled = 0;
266 			return;
267 		}
268 #endif
269 		/* get status */
270 		status = in_be16(&bdp->cbd_sc);
271 		/* If this one is empty, return happy */
272 		if (status & BD_SC_EMPTY)
273 			break;
274 
275 		/* get number of characters, and check spce in flip-buffer */
276 		i = in_be16(&bdp->cbd_datlen);
277 
278 		/* If we have not enough room in tty flip buffer, then we try
279 		 * later, which will be the next rx-interrupt or a timeout
280 		 */
281 		if (tty_buffer_request_room(tport, i) < i) {
282 			printk(KERN_WARNING "No room in flip buffer\n");
283 			return;
284 		}
285 
286 		/* get pointer */
287 		cp = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
288 
289 		/* loop through the buffer */
290 		while (i-- > 0) {
291 			ch = *cp++;
292 			port->icount.rx++;
293 			flg = TTY_NORMAL;
294 
295 			if (status &
296 			    (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
297 				goto handle_error;
298 			if (uart_handle_sysrq_char(port, ch))
299 				continue;
300 #ifdef CONFIG_CONSOLE_POLL
301 			if (unlikely(serial_polled)) {
302 				serial_polled = 0;
303 				return;
304 			}
305 #endif
306 		      error_return:
307 			tty_insert_flip_char(tport, ch, flg);
308 
309 		}		/* End while (i--) */
310 
311 		/* This BD is ready to be used again. Clear status. get next */
312 		clrbits16(&bdp->cbd_sc, BD_SC_BR | BD_SC_FR | BD_SC_PR |
313 		                        BD_SC_OV | BD_SC_ID);
314 		setbits16(&bdp->cbd_sc, BD_SC_EMPTY);
315 
316 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
317 			bdp = pinfo->rx_bd_base;
318 		else
319 			bdp++;
320 
321 	} /* End for (;;) */
322 
323 	/* Write back buffer pointer */
324 	pinfo->rx_cur = bdp;
325 
326 	/* activate BH processing */
327 	tty_flip_buffer_push(tport);
328 
329 	return;
330 
331 	/* Error processing */
332 
333       handle_error:
334 	/* Statistics */
335 	if (status & BD_SC_BR)
336 		port->icount.brk++;
337 	if (status & BD_SC_PR)
338 		port->icount.parity++;
339 	if (status & BD_SC_FR)
340 		port->icount.frame++;
341 	if (status & BD_SC_OV)
342 		port->icount.overrun++;
343 
344 	/* Mask out ignored conditions */
345 	status &= port->read_status_mask;
346 
347 	/* Handle the remaining ones */
348 	if (status & BD_SC_BR)
349 		flg = TTY_BREAK;
350 	else if (status & BD_SC_PR)
351 		flg = TTY_PARITY;
352 	else if (status & BD_SC_FR)
353 		flg = TTY_FRAME;
354 
355 	/* overrun does not affect the current character ! */
356 	if (status & BD_SC_OV) {
357 		ch = 0;
358 		flg = TTY_OVERRUN;
359 		/* We skip this buffer */
360 		/* CHECK: Is really nothing senseful there */
361 		/* ASSUMPTION: it contains nothing valid */
362 		i = 0;
363 	}
364 #ifdef SUPPORT_SYSRQ
365 	port->sysrq = 0;
366 #endif
367 	goto error_return;
368 }
369 
370 /*
371  * Asynchron mode interrupt handler
372  */
cpm_uart_int(int irq,void * data)373 static irqreturn_t cpm_uart_int(int irq, void *data)
374 {
375 	u8 events;
376 	struct uart_port *port = data;
377 	struct uart_cpm_port *pinfo = (struct uart_cpm_port *)port;
378 	smc_t __iomem *smcp = pinfo->smcp;
379 	scc_t __iomem *sccp = pinfo->sccp;
380 
381 	pr_debug("CPM uart[%d]:IRQ\n", port->line);
382 
383 	if (IS_SMC(pinfo)) {
384 		events = in_8(&smcp->smc_smce);
385 		out_8(&smcp->smc_smce, events);
386 		if (events & SMCM_BRKE)
387 			uart_handle_break(port);
388 		if (events & SMCM_RX)
389 			cpm_uart_int_rx(port);
390 		if (events & SMCM_TX)
391 			cpm_uart_int_tx(port);
392 	} else {
393 		events = in_be16(&sccp->scc_scce);
394 		out_be16(&sccp->scc_scce, events);
395 		if (events & UART_SCCM_BRKE)
396 			uart_handle_break(port);
397 		if (events & UART_SCCM_RX)
398 			cpm_uart_int_rx(port);
399 		if (events & UART_SCCM_TX)
400 			cpm_uart_int_tx(port);
401 	}
402 	return (events) ? IRQ_HANDLED : IRQ_NONE;
403 }
404 
cpm_uart_startup(struct uart_port * port)405 static int cpm_uart_startup(struct uart_port *port)
406 {
407 	int retval;
408 	struct uart_cpm_port *pinfo =
409 		container_of(port, struct uart_cpm_port, port);
410 
411 	pr_debug("CPM uart[%d]:startup\n", port->line);
412 
413 	/* If the port is not the console, make sure rx is disabled. */
414 	if (!(pinfo->flags & FLAG_CONSOLE)) {
415 		/* Disable UART rx */
416 		if (IS_SMC(pinfo)) {
417 			clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN);
418 			clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX);
419 		} else {
420 			clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR);
421 			clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
422 		}
423 		cpm_uart_initbd(pinfo);
424 		cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
425 	}
426 	/* Install interrupt handler. */
427 	retval = request_irq(port->irq, cpm_uart_int, 0, "cpm_uart", port);
428 	if (retval)
429 		return retval;
430 
431 	/* Startup rx-int */
432 	if (IS_SMC(pinfo)) {
433 		setbits8(&pinfo->smcp->smc_smcm, SMCM_RX);
434 		setbits16(&pinfo->smcp->smc_smcmr, (SMCMR_REN | SMCMR_TEN));
435 	} else {
436 		setbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
437 		setbits32(&pinfo->sccp->scc_gsmrl, (SCC_GSMRL_ENR | SCC_GSMRL_ENT));
438 	}
439 
440 	return 0;
441 }
442 
cpm_uart_wait_until_send(struct uart_cpm_port * pinfo)443 inline void cpm_uart_wait_until_send(struct uart_cpm_port *pinfo)
444 {
445 	set_current_state(TASK_UNINTERRUPTIBLE);
446 	schedule_timeout(pinfo->wait_closing);
447 }
448 
449 /*
450  * Shutdown the uart
451  */
cpm_uart_shutdown(struct uart_port * port)452 static void cpm_uart_shutdown(struct uart_port *port)
453 {
454 	struct uart_cpm_port *pinfo =
455 		container_of(port, struct uart_cpm_port, port);
456 
457 	pr_debug("CPM uart[%d]:shutdown\n", port->line);
458 
459 	/* free interrupt handler */
460 	free_irq(port->irq, port);
461 
462 	/* If the port is not the console, disable Rx and Tx. */
463 	if (!(pinfo->flags & FLAG_CONSOLE)) {
464 		/* Wait for all the BDs marked sent */
465 		while(!cpm_uart_tx_empty(port)) {
466 			set_current_state(TASK_UNINTERRUPTIBLE);
467 			schedule_timeout(2);
468 		}
469 
470 		if (pinfo->wait_closing)
471 			cpm_uart_wait_until_send(pinfo);
472 
473 		/* Stop uarts */
474 		if (IS_SMC(pinfo)) {
475 			smc_t __iomem *smcp = pinfo->smcp;
476 			clrbits16(&smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
477 			clrbits8(&smcp->smc_smcm, SMCM_RX | SMCM_TX);
478 		} else {
479 			scc_t __iomem *sccp = pinfo->sccp;
480 			clrbits32(&sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
481 			clrbits16(&sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
482 		}
483 
484 		/* Shut them really down and reinit buffer descriptors */
485 		if (IS_SMC(pinfo)) {
486 			out_be16(&pinfo->smcup->smc_brkcr, 0);
487 			cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
488 		} else {
489 			out_be16(&pinfo->sccup->scc_brkcr, 0);
490 			cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX);
491 		}
492 
493 		cpm_uart_initbd(pinfo);
494 	}
495 }
496 
cpm_uart_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)497 static void cpm_uart_set_termios(struct uart_port *port,
498                                  struct ktermios *termios,
499                                  struct ktermios *old)
500 {
501 	int baud;
502 	unsigned long flags;
503 	u16 cval, scval, prev_mode;
504 	int bits, sbits;
505 	struct uart_cpm_port *pinfo =
506 		container_of(port, struct uart_cpm_port, port);
507 	smc_t __iomem *smcp = pinfo->smcp;
508 	scc_t __iomem *sccp = pinfo->sccp;
509 	int maxidl;
510 
511 	pr_debug("CPM uart[%d]:set_termios\n", port->line);
512 
513 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
514 	if (baud < HW_BUF_SPD_THRESHOLD ||
515 	    (pinfo->port.state && pinfo->port.state->port.low_latency))
516 		pinfo->rx_fifosize = 1;
517 	else
518 		pinfo->rx_fifosize = RX_BUF_SIZE;
519 
520 	/* MAXIDL is the timeout after which a receive buffer is closed
521 	 * when not full if no more characters are received.
522 	 * We calculate it from the baudrate so that the duration is
523 	 * always the same at standard rates: about 4ms.
524 	 */
525 	maxidl = baud / 2400;
526 	if (maxidl < 1)
527 		maxidl = 1;
528 	if (maxidl > 0x10)
529 		maxidl = 0x10;
530 
531 	/* Character length programmed into the mode register is the
532 	 * sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
533 	 * 1 or 2 stop bits, minus 1.
534 	 * The value 'bits' counts this for us.
535 	 */
536 	cval = 0;
537 	scval = 0;
538 
539 	/* byte size */
540 	switch (termios->c_cflag & CSIZE) {
541 	case CS5:
542 		bits = 5;
543 		break;
544 	case CS6:
545 		bits = 6;
546 		break;
547 	case CS7:
548 		bits = 7;
549 		break;
550 	case CS8:
551 		bits = 8;
552 		break;
553 		/* Never happens, but GCC is too dumb to figure it out */
554 	default:
555 		bits = 8;
556 		break;
557 	}
558 	sbits = bits - 5;
559 
560 	if (termios->c_cflag & CSTOPB) {
561 		cval |= SMCMR_SL;	/* Two stops */
562 		scval |= SCU_PSMR_SL;
563 		bits++;
564 	}
565 
566 	if (termios->c_cflag & PARENB) {
567 		cval |= SMCMR_PEN;
568 		scval |= SCU_PSMR_PEN;
569 		bits++;
570 		if (!(termios->c_cflag & PARODD)) {
571 			cval |= SMCMR_PM_EVEN;
572 			scval |= (SCU_PSMR_REVP | SCU_PSMR_TEVP);
573 		}
574 	}
575 
576 	/*
577 	 * Update the timeout
578 	 */
579 	uart_update_timeout(port, termios->c_cflag, baud);
580 
581 	/*
582 	 * Set up parity check flag
583 	 */
584 #define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
585 
586 	port->read_status_mask = (BD_SC_EMPTY | BD_SC_OV);
587 	if (termios->c_iflag & INPCK)
588 		port->read_status_mask |= BD_SC_FR | BD_SC_PR;
589 	if ((termios->c_iflag & BRKINT) || (termios->c_iflag & PARMRK))
590 		port->read_status_mask |= BD_SC_BR;
591 
592 	/*
593 	 * Characters to ignore
594 	 */
595 	port->ignore_status_mask = 0;
596 	if (termios->c_iflag & IGNPAR)
597 		port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
598 	if (termios->c_iflag & IGNBRK) {
599 		port->ignore_status_mask |= BD_SC_BR;
600 		/*
601 		 * If we're ignore parity and break indicators, ignore
602 		 * overruns too.  (For real raw support).
603 		 */
604 		if (termios->c_iflag & IGNPAR)
605 			port->ignore_status_mask |= BD_SC_OV;
606 	}
607 	/*
608 	 * !!! ignore all characters if CREAD is not set
609 	 */
610 	if ((termios->c_cflag & CREAD) == 0)
611 		port->read_status_mask &= ~BD_SC_EMPTY;
612 
613 	spin_lock_irqsave(&port->lock, flags);
614 
615 	/* Start bit has not been added (so don't, because we would just
616 	 * subtract it later), and we need to add one for the number of
617 	 * stops bits (there is always at least one).
618 	 */
619 	bits++;
620 	if (IS_SMC(pinfo)) {
621 		/*
622 		 * MRBLR can be changed while an SMC/SCC is operating only
623 		 * if it is done in a single bus cycle with one 16-bit move
624 		 * (not two 8-bit bus cycles back-to-back). This occurs when
625 		 * the cp shifts control to the next RxBD, so the change does
626 		 * not take effect immediately. To guarantee the exact RxBD
627 		 * on which the change occurs, change MRBLR only while the
628 		 * SMC/SCC receiver is disabled.
629 		 */
630 		out_be16(&pinfo->smcup->smc_mrblr, pinfo->rx_fifosize);
631 		out_be16(&pinfo->smcup->smc_maxidl, maxidl);
632 
633 		/* Set the mode register.  We want to keep a copy of the
634 		 * enables, because we want to put them back if they were
635 		 * present.
636 		 */
637 		prev_mode = in_be16(&smcp->smc_smcmr) & (SMCMR_REN | SMCMR_TEN);
638 		/* Output in *one* operation, so we don't interrupt RX/TX if they
639 		 * were already enabled. */
640 		out_be16(&smcp->smc_smcmr, smcr_mk_clen(bits) | cval |
641 		    SMCMR_SM_UART | prev_mode);
642 	} else {
643 		out_be16(&pinfo->sccup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
644 		out_be16(&pinfo->sccup->scc_maxidl, maxidl);
645 		out_be16(&sccp->scc_psmr, (sbits << 12) | scval);
646 	}
647 
648 	if (pinfo->clk)
649 		clk_set_rate(pinfo->clk, baud);
650 	else
651 		cpm_set_brg(pinfo->brg - 1, baud);
652 	spin_unlock_irqrestore(&port->lock, flags);
653 }
654 
cpm_uart_type(struct uart_port * port)655 static const char *cpm_uart_type(struct uart_port *port)
656 {
657 	pr_debug("CPM uart[%d]:uart_type\n", port->line);
658 
659 	return port->type == PORT_CPM ? "CPM UART" : NULL;
660 }
661 
662 /*
663  * verify the new serial_struct (for TIOCSSERIAL).
664  */
cpm_uart_verify_port(struct uart_port * port,struct serial_struct * ser)665 static int cpm_uart_verify_port(struct uart_port *port,
666 				struct serial_struct *ser)
667 {
668 	int ret = 0;
669 
670 	pr_debug("CPM uart[%d]:verify_port\n", port->line);
671 
672 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
673 		ret = -EINVAL;
674 	if (ser->irq < 0 || ser->irq >= nr_irqs)
675 		ret = -EINVAL;
676 	if (ser->baud_base < 9600)
677 		ret = -EINVAL;
678 	return ret;
679 }
680 
681 /*
682  * Transmit characters, refill buffer descriptor, if possible
683  */
cpm_uart_tx_pump(struct uart_port * port)684 static int cpm_uart_tx_pump(struct uart_port *port)
685 {
686 	cbd_t __iomem *bdp;
687 	u8 *p;
688 	int count;
689 	struct uart_cpm_port *pinfo =
690 		container_of(port, struct uart_cpm_port, port);
691 	struct circ_buf *xmit = &port->state->xmit;
692 
693 	/* Handle xon/xoff */
694 	if (port->x_char) {
695 		/* Pick next descriptor and fill from buffer */
696 		bdp = pinfo->tx_cur;
697 
698 		p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
699 
700 		*p++ = port->x_char;
701 
702 		out_be16(&bdp->cbd_datlen, 1);
703 		setbits16(&bdp->cbd_sc, BD_SC_READY);
704 		/* Get next BD. */
705 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
706 			bdp = pinfo->tx_bd_base;
707 		else
708 			bdp++;
709 		pinfo->tx_cur = bdp;
710 
711 		port->icount.tx++;
712 		port->x_char = 0;
713 		return 1;
714 	}
715 
716 	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
717 		cpm_uart_stop_tx(port);
718 		return 0;
719 	}
720 
721 	/* Pick next descriptor and fill from buffer */
722 	bdp = pinfo->tx_cur;
723 
724 	while (!(in_be16(&bdp->cbd_sc) & BD_SC_READY) &&
725 	       xmit->tail != xmit->head) {
726 		count = 0;
727 		p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
728 		while (count < pinfo->tx_fifosize) {
729 			*p++ = xmit->buf[xmit->tail];
730 			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
731 			port->icount.tx++;
732 			count++;
733 			if (xmit->head == xmit->tail)
734 				break;
735 		}
736 		out_be16(&bdp->cbd_datlen, count);
737 		setbits16(&bdp->cbd_sc, BD_SC_READY);
738 		/* Get next BD. */
739 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
740 			bdp = pinfo->tx_bd_base;
741 		else
742 			bdp++;
743 	}
744 	pinfo->tx_cur = bdp;
745 
746 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
747 		uart_write_wakeup(port);
748 
749 	if (uart_circ_empty(xmit)) {
750 		cpm_uart_stop_tx(port);
751 		return 0;
752 	}
753 
754 	return 1;
755 }
756 
757 /*
758  * init buffer descriptors
759  */
cpm_uart_initbd(struct uart_cpm_port * pinfo)760 static void cpm_uart_initbd(struct uart_cpm_port *pinfo)
761 {
762 	int i;
763 	u8 *mem_addr;
764 	cbd_t __iomem *bdp;
765 
766 	pr_debug("CPM uart[%d]:initbd\n", pinfo->port.line);
767 
768 	/* Set the physical address of the host memory
769 	 * buffers in the buffer descriptors, and the
770 	 * virtual address for us to work with.
771 	 */
772 	mem_addr = pinfo->mem_addr;
773 	bdp = pinfo->rx_cur = pinfo->rx_bd_base;
774 	for (i = 0; i < (pinfo->rx_nrfifos - 1); i++, bdp++) {
775 		out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
776 		out_be16(&bdp->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT);
777 		mem_addr += pinfo->rx_fifosize;
778 	}
779 
780 	out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
781 	out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
782 
783 	/* Set the physical address of the host memory
784 	 * buffers in the buffer descriptors, and the
785 	 * virtual address for us to work with.
786 	 */
787 	mem_addr = pinfo->mem_addr + L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize);
788 	bdp = pinfo->tx_cur = pinfo->tx_bd_base;
789 	for (i = 0; i < (pinfo->tx_nrfifos - 1); i++, bdp++) {
790 		out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
791 		out_be16(&bdp->cbd_sc, BD_SC_INTRPT);
792 		mem_addr += pinfo->tx_fifosize;
793 	}
794 
795 	out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
796 	out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_INTRPT);
797 }
798 
cpm_uart_init_scc(struct uart_cpm_port * pinfo)799 static void cpm_uart_init_scc(struct uart_cpm_port *pinfo)
800 {
801 	scc_t __iomem *scp;
802 	scc_uart_t __iomem *sup;
803 
804 	pr_debug("CPM uart[%d]:init_scc\n", pinfo->port.line);
805 
806 	scp = pinfo->sccp;
807 	sup = pinfo->sccup;
808 
809 	/* Store address */
810 	out_be16(&pinfo->sccup->scc_genscc.scc_rbase,
811 	         (u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE);
812 	out_be16(&pinfo->sccup->scc_genscc.scc_tbase,
813 	         (u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE);
814 
815 	/* Set up the uart parameters in the
816 	 * parameter ram.
817 	 */
818 
819 	cpm_set_scc_fcr(sup);
820 
821 	out_be16(&sup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
822 	out_be16(&sup->scc_maxidl, 0x10);
823 	out_be16(&sup->scc_brkcr, 1);
824 	out_be16(&sup->scc_parec, 0);
825 	out_be16(&sup->scc_frmec, 0);
826 	out_be16(&sup->scc_nosec, 0);
827 	out_be16(&sup->scc_brkec, 0);
828 	out_be16(&sup->scc_uaddr1, 0);
829 	out_be16(&sup->scc_uaddr2, 0);
830 	out_be16(&sup->scc_toseq, 0);
831 	out_be16(&sup->scc_char1, 0x8000);
832 	out_be16(&sup->scc_char2, 0x8000);
833 	out_be16(&sup->scc_char3, 0x8000);
834 	out_be16(&sup->scc_char4, 0x8000);
835 	out_be16(&sup->scc_char5, 0x8000);
836 	out_be16(&sup->scc_char6, 0x8000);
837 	out_be16(&sup->scc_char7, 0x8000);
838 	out_be16(&sup->scc_char8, 0x8000);
839 	out_be16(&sup->scc_rccm, 0xc0ff);
840 
841 	/* Send the CPM an initialize command.
842 	 */
843 	cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
844 
845 	/* Set UART mode, 8 bit, no parity, one stop.
846 	 * Enable receive and transmit.
847 	 */
848 	out_be32(&scp->scc_gsmrh, 0);
849 	out_be32(&scp->scc_gsmrl,
850 	         SCC_GSMRL_MODE_UART | SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16);
851 
852 	/* Enable rx interrupts  and clear all pending events.  */
853 	out_be16(&scp->scc_sccm, 0);
854 	out_be16(&scp->scc_scce, 0xffff);
855 	out_be16(&scp->scc_dsr, 0x7e7e);
856 	out_be16(&scp->scc_psmr, 0x3000);
857 
858 	setbits32(&scp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
859 }
860 
cpm_uart_init_smc(struct uart_cpm_port * pinfo)861 static void cpm_uart_init_smc(struct uart_cpm_port *pinfo)
862 {
863 	smc_t __iomem *sp;
864 	smc_uart_t __iomem *up;
865 
866 	pr_debug("CPM uart[%d]:init_smc\n", pinfo->port.line);
867 
868 	sp = pinfo->smcp;
869 	up = pinfo->smcup;
870 
871 	/* Store address */
872 	out_be16(&pinfo->smcup->smc_rbase,
873 	         (u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE);
874 	out_be16(&pinfo->smcup->smc_tbase,
875 	         (u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE);
876 
877 /*
878  *  In case SMC1 is being relocated...
879  */
880 #if defined (CONFIG_I2C_SPI_SMC1_UCODE_PATCH)
881 	out_be16(&up->smc_rbptr, in_be16(&pinfo->smcup->smc_rbase));
882 	out_be16(&up->smc_tbptr, in_be16(&pinfo->smcup->smc_tbase));
883 	out_be32(&up->smc_rstate, 0);
884 	out_be32(&up->smc_tstate, 0);
885 	out_be16(&up->smc_brkcr, 1);              /* number of break chars */
886 	out_be16(&up->smc_brkec, 0);
887 #endif
888 
889 	/* Set up the uart parameters in the
890 	 * parameter ram.
891 	 */
892 	cpm_set_smc_fcr(up);
893 
894 	/* Using idle character time requires some additional tuning.  */
895 	out_be16(&up->smc_mrblr, pinfo->rx_fifosize);
896 	out_be16(&up->smc_maxidl, 0x10);
897 	out_be16(&up->smc_brklen, 0);
898 	out_be16(&up->smc_brkec, 0);
899 	out_be16(&up->smc_brkcr, 1);
900 
901 	cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
902 
903 	/* Set UART mode, 8 bit, no parity, one stop.
904 	 * Enable receive and transmit.
905 	 */
906 	out_be16(&sp->smc_smcmr, smcr_mk_clen(9) | SMCMR_SM_UART);
907 
908 	/* Enable only rx interrupts clear all pending events. */
909 	out_8(&sp->smc_smcm, 0);
910 	out_8(&sp->smc_smce, 0xff);
911 
912 	setbits16(&sp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
913 }
914 
915 /*
916  * Initialize port. This is called from early_console stuff
917  * so we have to be careful here !
918  */
cpm_uart_request_port(struct uart_port * port)919 static int cpm_uart_request_port(struct uart_port *port)
920 {
921 	struct uart_cpm_port *pinfo =
922 		container_of(port, struct uart_cpm_port, port);
923 	int ret;
924 
925 	pr_debug("CPM uart[%d]:request port\n", port->line);
926 
927 	if (pinfo->flags & FLAG_CONSOLE)
928 		return 0;
929 
930 	if (IS_SMC(pinfo)) {
931 		clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX);
932 		clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
933 	} else {
934 		clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
935 		clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
936 	}
937 
938 	ret = cpm_uart_allocbuf(pinfo, 0);
939 
940 	if (ret)
941 		return ret;
942 
943 	cpm_uart_initbd(pinfo);
944 	if (IS_SMC(pinfo))
945 		cpm_uart_init_smc(pinfo);
946 	else
947 		cpm_uart_init_scc(pinfo);
948 
949 	return 0;
950 }
951 
cpm_uart_release_port(struct uart_port * port)952 static void cpm_uart_release_port(struct uart_port *port)
953 {
954 	struct uart_cpm_port *pinfo =
955 		container_of(port, struct uart_cpm_port, port);
956 
957 	if (!(pinfo->flags & FLAG_CONSOLE))
958 		cpm_uart_freebuf(pinfo);
959 }
960 
961 /*
962  * Configure/autoconfigure the port.
963  */
cpm_uart_config_port(struct uart_port * port,int flags)964 static void cpm_uart_config_port(struct uart_port *port, int flags)
965 {
966 	pr_debug("CPM uart[%d]:config_port\n", port->line);
967 
968 	if (flags & UART_CONFIG_TYPE) {
969 		port->type = PORT_CPM;
970 		cpm_uart_request_port(port);
971 	}
972 }
973 
974 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_CPM_CONSOLE)
975 /*
976  * Write a string to the serial port
977  * Note that this is called with interrupts already disabled
978  */
cpm_uart_early_write(struct uart_cpm_port * pinfo,const char * string,u_int count,bool handle_linefeed)979 static void cpm_uart_early_write(struct uart_cpm_port *pinfo,
980 		const char *string, u_int count, bool handle_linefeed)
981 {
982 	unsigned int i;
983 	cbd_t __iomem *bdp, *bdbase;
984 	unsigned char *cpm_outp_addr;
985 
986 	/* Get the address of the host memory buffer.
987 	 */
988 	bdp = pinfo->tx_cur;
989 	bdbase = pinfo->tx_bd_base;
990 
991 	/*
992 	 * Now, do each character.  This is not as bad as it looks
993 	 * since this is a holding FIFO and not a transmitting FIFO.
994 	 * We could add the complexity of filling the entire transmit
995 	 * buffer, but we would just wait longer between accesses......
996 	 */
997 	for (i = 0; i < count; i++, string++) {
998 		/* Wait for transmitter fifo to empty.
999 		 * Ready indicates output is ready, and xmt is doing
1000 		 * that, not that it is ready for us to send.
1001 		 */
1002 		while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
1003 			;
1004 
1005 		/* Send the character out.
1006 		 * If the buffer address is in the CPM DPRAM, don't
1007 		 * convert it.
1008 		 */
1009 		cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr),
1010 					pinfo);
1011 		*cpm_outp_addr = *string;
1012 
1013 		out_be16(&bdp->cbd_datlen, 1);
1014 		setbits16(&bdp->cbd_sc, BD_SC_READY);
1015 
1016 		if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
1017 			bdp = bdbase;
1018 		else
1019 			bdp++;
1020 
1021 		/* if a LF, also do CR... */
1022 		if (handle_linefeed && *string == 10) {
1023 			while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
1024 				;
1025 
1026 			cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr),
1027 						pinfo);
1028 			*cpm_outp_addr = 13;
1029 
1030 			out_be16(&bdp->cbd_datlen, 1);
1031 			setbits16(&bdp->cbd_sc, BD_SC_READY);
1032 
1033 			if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
1034 				bdp = bdbase;
1035 			else
1036 				bdp++;
1037 		}
1038 	}
1039 
1040 	/*
1041 	 * Finally, Wait for transmitter & holding register to empty
1042 	 *  and restore the IER
1043 	 */
1044 	while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
1045 		;
1046 
1047 	pinfo->tx_cur = bdp;
1048 }
1049 #endif
1050 
1051 #ifdef CONFIG_CONSOLE_POLL
1052 /* Serial polling routines for writing and reading from the uart while
1053  * in an interrupt or debug context.
1054  */
1055 
1056 #define GDB_BUF_SIZE	512	/* power of 2, please */
1057 
1058 static char poll_buf[GDB_BUF_SIZE];
1059 static char *pollp;
1060 static int poll_chars;
1061 
poll_wait_key(char * obuf,struct uart_cpm_port * pinfo)1062 static int poll_wait_key(char *obuf, struct uart_cpm_port *pinfo)
1063 {
1064 	u_char		c, *cp;
1065 	volatile cbd_t	*bdp;
1066 	int		i;
1067 
1068 	/* Get the address of the host memory buffer.
1069 	 */
1070 	bdp = pinfo->rx_cur;
1071 	while (bdp->cbd_sc & BD_SC_EMPTY)
1072 		;
1073 
1074 	/* If the buffer address is in the CPM DPRAM, don't
1075 	 * convert it.
1076 	 */
1077 	cp = cpm2cpu_addr(bdp->cbd_bufaddr, pinfo);
1078 
1079 	if (obuf) {
1080 		i = c = bdp->cbd_datlen;
1081 		while (i-- > 0)
1082 			*obuf++ = *cp++;
1083 	} else
1084 		c = *cp;
1085 	bdp->cbd_sc &= ~(BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV | BD_SC_ID);
1086 	bdp->cbd_sc |= BD_SC_EMPTY;
1087 
1088 	if (bdp->cbd_sc & BD_SC_WRAP)
1089 		bdp = pinfo->rx_bd_base;
1090 	else
1091 		bdp++;
1092 	pinfo->rx_cur = (cbd_t *)bdp;
1093 
1094 	return (int)c;
1095 }
1096 
cpm_get_poll_char(struct uart_port * port)1097 static int cpm_get_poll_char(struct uart_port *port)
1098 {
1099 	struct uart_cpm_port *pinfo =
1100 		container_of(port, struct uart_cpm_port, port);
1101 
1102 	if (!serial_polled) {
1103 		serial_polled = 1;
1104 		poll_chars = 0;
1105 	}
1106 	if (poll_chars <= 0) {
1107 		poll_chars = poll_wait_key(poll_buf, pinfo);
1108 		pollp = poll_buf;
1109 	}
1110 	poll_chars--;
1111 	return *pollp++;
1112 }
1113 
cpm_put_poll_char(struct uart_port * port,unsigned char c)1114 static void cpm_put_poll_char(struct uart_port *port,
1115 			 unsigned char c)
1116 {
1117 	struct uart_cpm_port *pinfo =
1118 		container_of(port, struct uart_cpm_port, port);
1119 	static char ch[2];
1120 
1121 	ch[0] = (char)c;
1122 	cpm_uart_early_write(pinfo, ch, 1, false);
1123 }
1124 #endif /* CONFIG_CONSOLE_POLL */
1125 
1126 static struct uart_ops cpm_uart_pops = {
1127 	.tx_empty	= cpm_uart_tx_empty,
1128 	.set_mctrl	= cpm_uart_set_mctrl,
1129 	.get_mctrl	= cpm_uart_get_mctrl,
1130 	.stop_tx	= cpm_uart_stop_tx,
1131 	.start_tx	= cpm_uart_start_tx,
1132 	.stop_rx	= cpm_uart_stop_rx,
1133 	.break_ctl	= cpm_uart_break_ctl,
1134 	.startup	= cpm_uart_startup,
1135 	.shutdown	= cpm_uart_shutdown,
1136 	.set_termios	= cpm_uart_set_termios,
1137 	.type		= cpm_uart_type,
1138 	.release_port	= cpm_uart_release_port,
1139 	.request_port	= cpm_uart_request_port,
1140 	.config_port	= cpm_uart_config_port,
1141 	.verify_port	= cpm_uart_verify_port,
1142 #ifdef CONFIG_CONSOLE_POLL
1143 	.poll_get_char = cpm_get_poll_char,
1144 	.poll_put_char = cpm_put_poll_char,
1145 #endif
1146 };
1147 
1148 struct uart_cpm_port cpm_uart_ports[UART_NR];
1149 
cpm_uart_init_port(struct device_node * np,struct uart_cpm_port * pinfo)1150 static int cpm_uart_init_port(struct device_node *np,
1151                               struct uart_cpm_port *pinfo)
1152 {
1153 	const u32 *data;
1154 	void __iomem *mem, *pram;
1155 	int len;
1156 	int ret;
1157 	int i;
1158 
1159 	data = of_get_property(np, "clock", NULL);
1160 	if (data) {
1161 		struct clk *clk = clk_get(NULL, (const char*)data);
1162 		if (!IS_ERR(clk))
1163 			pinfo->clk = clk;
1164 	}
1165 	if (!pinfo->clk) {
1166 		data = of_get_property(np, "fsl,cpm-brg", &len);
1167 		if (!data || len != 4) {
1168 			printk(KERN_ERR "CPM UART %s has no/invalid "
1169 			                "fsl,cpm-brg property.\n", np->name);
1170 			return -EINVAL;
1171 		}
1172 		pinfo->brg = *data;
1173 	}
1174 
1175 	data = of_get_property(np, "fsl,cpm-command", &len);
1176 	if (!data || len != 4) {
1177 		printk(KERN_ERR "CPM UART %s has no/invalid "
1178 		                "fsl,cpm-command property.\n", np->name);
1179 		return -EINVAL;
1180 	}
1181 	pinfo->command = *data;
1182 
1183 	mem = of_iomap(np, 0);
1184 	if (!mem)
1185 		return -ENOMEM;
1186 
1187 	if (of_device_is_compatible(np, "fsl,cpm1-scc-uart") ||
1188 	    of_device_is_compatible(np, "fsl,cpm2-scc-uart")) {
1189 		pinfo->sccp = mem;
1190 		pinfo->sccup = pram = cpm_uart_map_pram(pinfo, np);
1191 	} else if (of_device_is_compatible(np, "fsl,cpm1-smc-uart") ||
1192 	           of_device_is_compatible(np, "fsl,cpm2-smc-uart")) {
1193 		pinfo->flags |= FLAG_SMC;
1194 		pinfo->smcp = mem;
1195 		pinfo->smcup = pram = cpm_uart_map_pram(pinfo, np);
1196 	} else {
1197 		ret = -ENODEV;
1198 		goto out_mem;
1199 	}
1200 
1201 	if (!pram) {
1202 		ret = -ENOMEM;
1203 		goto out_mem;
1204 	}
1205 
1206 	pinfo->tx_nrfifos = TX_NUM_FIFO;
1207 	pinfo->tx_fifosize = TX_BUF_SIZE;
1208 	pinfo->rx_nrfifos = RX_NUM_FIFO;
1209 	pinfo->rx_fifosize = RX_BUF_SIZE;
1210 
1211 	pinfo->port.uartclk = ppc_proc_freq;
1212 	pinfo->port.mapbase = (unsigned long)mem;
1213 	pinfo->port.type = PORT_CPM;
1214 	pinfo->port.ops = &cpm_uart_pops,
1215 	pinfo->port.iotype = UPIO_MEM;
1216 	pinfo->port.fifosize = pinfo->tx_nrfifos * pinfo->tx_fifosize;
1217 	spin_lock_init(&pinfo->port.lock);
1218 
1219 	pinfo->port.irq = irq_of_parse_and_map(np, 0);
1220 	if (pinfo->port.irq == NO_IRQ) {
1221 		ret = -EINVAL;
1222 		goto out_pram;
1223 	}
1224 
1225 	for (i = 0; i < NUM_GPIOS; i++) {
1226 		int gpio;
1227 
1228 		pinfo->gpios[i] = -1;
1229 
1230 		gpio = of_get_gpio(np, i);
1231 
1232 		if (gpio_is_valid(gpio)) {
1233 			ret = gpio_request(gpio, "cpm_uart");
1234 			if (ret) {
1235 				pr_err("can't request gpio #%d: %d\n", i, ret);
1236 				continue;
1237 			}
1238 			if (i == GPIO_RTS || i == GPIO_DTR)
1239 				ret = gpio_direction_output(gpio, 0);
1240 			else
1241 				ret = gpio_direction_input(gpio);
1242 			if (ret) {
1243 				pr_err("can't set direction for gpio #%d: %d\n",
1244 					i, ret);
1245 				gpio_free(gpio);
1246 				continue;
1247 			}
1248 			pinfo->gpios[i] = gpio;
1249 		}
1250 	}
1251 
1252 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
1253 	udbg_putc = NULL;
1254 #endif
1255 
1256 	return cpm_uart_request_port(&pinfo->port);
1257 
1258 out_pram:
1259 	cpm_uart_unmap_pram(pinfo, pram);
1260 out_mem:
1261 	iounmap(mem);
1262 	return ret;
1263 }
1264 
1265 #ifdef CONFIG_SERIAL_CPM_CONSOLE
1266 /*
1267  *	Print a string to the serial port trying not to disturb
1268  *	any possible real use of the port...
1269  *
1270  *	Note that this is called with interrupts already disabled
1271  */
cpm_uart_console_write(struct console * co,const char * s,u_int count)1272 static void cpm_uart_console_write(struct console *co, const char *s,
1273 				   u_int count)
1274 {
1275 	struct uart_cpm_port *pinfo = &cpm_uart_ports[co->index];
1276 	unsigned long flags;
1277 	int nolock = oops_in_progress;
1278 
1279 	if (unlikely(nolock)) {
1280 		local_irq_save(flags);
1281 	} else {
1282 		spin_lock_irqsave(&pinfo->port.lock, flags);
1283 	}
1284 
1285 	cpm_uart_early_write(pinfo, s, count, true);
1286 
1287 	if (unlikely(nolock)) {
1288 		local_irq_restore(flags);
1289 	} else {
1290 		spin_unlock_irqrestore(&pinfo->port.lock, flags);
1291 	}
1292 }
1293 
1294 
cpm_uart_console_setup(struct console * co,char * options)1295 static int __init cpm_uart_console_setup(struct console *co, char *options)
1296 {
1297 	int baud = 38400;
1298 	int bits = 8;
1299 	int parity = 'n';
1300 	int flow = 'n';
1301 	int ret;
1302 	struct uart_cpm_port *pinfo;
1303 	struct uart_port *port;
1304 
1305 	struct device_node *np = NULL;
1306 	int i = 0;
1307 
1308 	if (co->index >= UART_NR) {
1309 		printk(KERN_ERR "cpm_uart: console index %d too high\n",
1310 		       co->index);
1311 		return -ENODEV;
1312 	}
1313 
1314 	do {
1315 		np = of_find_node_by_type(np, "serial");
1316 		if (!np)
1317 			return -ENODEV;
1318 
1319 		if (!of_device_is_compatible(np, "fsl,cpm1-smc-uart") &&
1320 		    !of_device_is_compatible(np, "fsl,cpm1-scc-uart") &&
1321 		    !of_device_is_compatible(np, "fsl,cpm2-smc-uart") &&
1322 		    !of_device_is_compatible(np, "fsl,cpm2-scc-uart"))
1323 			i--;
1324 	} while (i++ != co->index);
1325 
1326 	pinfo = &cpm_uart_ports[co->index];
1327 
1328 	pinfo->flags |= FLAG_CONSOLE;
1329 	port = &pinfo->port;
1330 
1331 	ret = cpm_uart_init_port(np, pinfo);
1332 	of_node_put(np);
1333 	if (ret)
1334 		return ret;
1335 
1336 	if (options) {
1337 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1338 	} else {
1339 		if ((baud = uart_baudrate()) == -1)
1340 			baud = 9600;
1341 	}
1342 
1343 	if (IS_SMC(pinfo)) {
1344 		out_be16(&pinfo->smcup->smc_brkcr, 0);
1345 		cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
1346 		clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX);
1347 		clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
1348 	} else {
1349 		out_be16(&pinfo->sccup->scc_brkcr, 0);
1350 		cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX);
1351 		clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
1352 		clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
1353 	}
1354 
1355 	ret = cpm_uart_allocbuf(pinfo, 1);
1356 
1357 	if (ret)
1358 		return ret;
1359 
1360 	cpm_uart_initbd(pinfo);
1361 
1362 	if (IS_SMC(pinfo))
1363 		cpm_uart_init_smc(pinfo);
1364 	else
1365 		cpm_uart_init_scc(pinfo);
1366 
1367 	uart_set_options(port, co, baud, parity, bits, flow);
1368 	cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX);
1369 
1370 	return 0;
1371 }
1372 
1373 static struct uart_driver cpm_reg;
1374 static struct console cpm_scc_uart_console = {
1375 	.name		= "ttyCPM",
1376 	.write		= cpm_uart_console_write,
1377 	.device		= uart_console_device,
1378 	.setup		= cpm_uart_console_setup,
1379 	.flags		= CON_PRINTBUFFER,
1380 	.index		= -1,
1381 	.data		= &cpm_reg,
1382 };
1383 
cpm_uart_console_init(void)1384 static int __init cpm_uart_console_init(void)
1385 {
1386 	register_console(&cpm_scc_uart_console);
1387 	return 0;
1388 }
1389 
1390 console_initcall(cpm_uart_console_init);
1391 
1392 #define CPM_UART_CONSOLE	&cpm_scc_uart_console
1393 #else
1394 #define CPM_UART_CONSOLE	NULL
1395 #endif
1396 
1397 static struct uart_driver cpm_reg = {
1398 	.owner		= THIS_MODULE,
1399 	.driver_name	= "ttyCPM",
1400 	.dev_name	= "ttyCPM",
1401 	.major		= SERIAL_CPM_MAJOR,
1402 	.minor		= SERIAL_CPM_MINOR,
1403 	.cons		= CPM_UART_CONSOLE,
1404 	.nr		= UART_NR,
1405 };
1406 
1407 static int probe_index;
1408 
cpm_uart_probe(struct platform_device * ofdev)1409 static int cpm_uart_probe(struct platform_device *ofdev)
1410 {
1411 	int index = probe_index++;
1412 	struct uart_cpm_port *pinfo = &cpm_uart_ports[index];
1413 	int ret;
1414 
1415 	pinfo->port.line = index;
1416 
1417 	if (index >= UART_NR)
1418 		return -ENODEV;
1419 
1420 	platform_set_drvdata(ofdev, pinfo);
1421 
1422 	/* initialize the device pointer for the port */
1423 	pinfo->port.dev = &ofdev->dev;
1424 
1425 	ret = cpm_uart_init_port(ofdev->dev.of_node, pinfo);
1426 	if (ret)
1427 		return ret;
1428 
1429 	return uart_add_one_port(&cpm_reg, &pinfo->port);
1430 }
1431 
cpm_uart_remove(struct platform_device * ofdev)1432 static int cpm_uart_remove(struct platform_device *ofdev)
1433 {
1434 	struct uart_cpm_port *pinfo = platform_get_drvdata(ofdev);
1435 	return uart_remove_one_port(&cpm_reg, &pinfo->port);
1436 }
1437 
1438 static const struct of_device_id cpm_uart_match[] = {
1439 	{
1440 		.compatible = "fsl,cpm1-smc-uart",
1441 	},
1442 	{
1443 		.compatible = "fsl,cpm1-scc-uart",
1444 	},
1445 	{
1446 		.compatible = "fsl,cpm2-smc-uart",
1447 	},
1448 	{
1449 		.compatible = "fsl,cpm2-scc-uart",
1450 	},
1451 	{}
1452 };
1453 MODULE_DEVICE_TABLE(of, cpm_uart_match);
1454 
1455 static struct platform_driver cpm_uart_driver = {
1456 	.driver = {
1457 		.name = "cpm_uart",
1458 		.of_match_table = cpm_uart_match,
1459 	},
1460 	.probe = cpm_uart_probe,
1461 	.remove = cpm_uart_remove,
1462  };
1463 
cpm_uart_init(void)1464 static int __init cpm_uart_init(void)
1465 {
1466 	int ret = uart_register_driver(&cpm_reg);
1467 	if (ret)
1468 		return ret;
1469 
1470 	ret = platform_driver_register(&cpm_uart_driver);
1471 	if (ret)
1472 		uart_unregister_driver(&cpm_reg);
1473 
1474 	return ret;
1475 }
1476 
cpm_uart_exit(void)1477 static void __exit cpm_uart_exit(void)
1478 {
1479 	platform_driver_unregister(&cpm_uart_driver);
1480 	uart_unregister_driver(&cpm_reg);
1481 }
1482 
1483 module_init(cpm_uart_init);
1484 module_exit(cpm_uart_exit);
1485 
1486 MODULE_AUTHOR("Kumar Gala/Antoniou Pantelis");
1487 MODULE_DESCRIPTION("CPM SCC/SMC port driver $Revision: 0.01 $");
1488 MODULE_LICENSE("GPL");
1489 MODULE_ALIAS_CHARDEV(SERIAL_CPM_MAJOR, SERIAL_CPM_MINOR);
1490