1 /*
2  * Driver for the PSC of the Freescale MPC52xx PSCs configured as UARTs.
3  *
4  * FIXME According to the usermanual the status bits in the status register
5  * are only updated when the peripherals access the FIFO and not when the
6  * CPU access them. So since we use this bits to know when we stop writing
7  * and reading, they may not be updated in-time and a race condition may
8  * exists. But I haven't be able to prove this and I don't care. But if
9  * any problem arises, it might worth checking. The TX/RX FIFO Stats
10  * registers should be used in addition.
11  * Update: Actually, they seem updated ... At least the bits we use.
12  *
13  *
14  * Maintainer : Sylvain Munaut <tnt@246tNt.com>
15  *
16  * Some of the code has been inspired/copied from the 2.4 code written
17  * by Dale Farnsworth <dfarnsworth@mvista.com>.
18  *
19  * Copyright (C) 2008 Freescale Semiconductor Inc.
20  *                    John Rigby <jrigby@gmail.com>
21  * Added support for MPC5121
22  * Copyright (C) 2006 Secret Lab Technologies Ltd.
23  *                    Grant Likely <grant.likely@secretlab.ca>
24  * Copyright (C) 2004-2006 Sylvain Munaut <tnt@246tNt.com>
25  * Copyright (C) 2003 MontaVista, Software, Inc.
26  *
27  * This file is licensed under the terms of the GNU General Public License
28  * version 2. This program is licensed "as is" without any warranty of any
29  * kind, whether express or implied.
30  */
31 
32 #undef DEBUG
33 
34 #include <linux/device.h>
35 #include <linux/module.h>
36 #include <linux/tty.h>
37 #include <linux/tty_flip.h>
38 #include <linux/serial.h>
39 #include <linux/sysrq.h>
40 #include <linux/console.h>
41 #include <linux/delay.h>
42 #include <linux/io.h>
43 #include <linux/of.h>
44 #include <linux/of_platform.h>
45 #include <linux/clk.h>
46 
47 #include <asm/mpc52xx.h>
48 #include <asm/mpc52xx_psc.h>
49 
50 #if defined(CONFIG_SERIAL_MPC52xx_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
51 #define SUPPORT_SYSRQ
52 #endif
53 
54 #include <linux/serial_core.h>
55 
56 
57 /* We've been assigned a range on the "Low-density serial ports" major */
58 #define SERIAL_PSC_MAJOR	204
59 #define SERIAL_PSC_MINOR	148
60 
61 
62 #define ISR_PASS_LIMIT 256	/* Max number of iteration in the interrupt */
63 
64 
65 static struct uart_port mpc52xx_uart_ports[MPC52xx_PSC_MAXNUM];
66 	/* Rem: - We use the read_status_mask as a shadow of
67 	 *        psc->mpc52xx_psc_imr
68 	 *      - It's important that is array is all zero on start as we
69 	 *        use it to know if it's initialized or not ! If it's not sure
70 	 *        it's cleared, then a memset(...,0,...) should be added to
71 	 *        the console_init
72 	 */
73 
74 /* lookup table for matching device nodes to index numbers */
75 static struct device_node *mpc52xx_uart_nodes[MPC52xx_PSC_MAXNUM];
76 
77 static void mpc52xx_uart_of_enumerate(void);
78 
79 
80 #define PSC(port) ((struct mpc52xx_psc __iomem *)((port)->membase))
81 
82 
83 /* Forward declaration of the interruption handling routine */
84 static irqreturn_t mpc52xx_uart_int(int irq, void *dev_id);
85 static irqreturn_t mpc5xxx_uart_process_int(struct uart_port *port);
86 
87 
88 /* Simple macro to test if a port is console or not. This one is taken
89  * for serial_core.c and maybe should be moved to serial_core.h ? */
90 #ifdef CONFIG_SERIAL_CORE_CONSOLE
91 #define uart_console(port) \
92 	((port)->cons && (port)->cons->index == (port)->line)
93 #else
94 #define uart_console(port)	(0)
95 #endif
96 
97 /* ======================================================================== */
98 /* PSC fifo operations for isolating differences between 52xx and 512x      */
99 /* ======================================================================== */
100 
101 struct psc_ops {
102 	void		(*fifo_init)(struct uart_port *port);
103 	int		(*raw_rx_rdy)(struct uart_port *port);
104 	int		(*raw_tx_rdy)(struct uart_port *port);
105 	int		(*rx_rdy)(struct uart_port *port);
106 	int		(*tx_rdy)(struct uart_port *port);
107 	int		(*tx_empty)(struct uart_port *port);
108 	void		(*stop_rx)(struct uart_port *port);
109 	void		(*start_tx)(struct uart_port *port);
110 	void		(*stop_tx)(struct uart_port *port);
111 	void		(*rx_clr_irq)(struct uart_port *port);
112 	void		(*tx_clr_irq)(struct uart_port *port);
113 	void		(*write_char)(struct uart_port *port, unsigned char c);
114 	unsigned char	(*read_char)(struct uart_port *port);
115 	void		(*cw_disable_ints)(struct uart_port *port);
116 	void		(*cw_restore_ints)(struct uart_port *port);
117 	unsigned int	(*set_baudrate)(struct uart_port *port,
118 					struct ktermios *new,
119 					struct ktermios *old);
120 	int		(*clock)(struct uart_port *port, int enable);
121 	int		(*fifoc_init)(void);
122 	void		(*fifoc_uninit)(void);
123 	void		(*get_irq)(struct uart_port *, struct device_node *);
124 	irqreturn_t	(*handle_irq)(struct uart_port *port);
125 };
126 
127 /* setting the prescaler and divisor reg is common for all chips */
128 static inline void mpc52xx_set_divisor(struct mpc52xx_psc __iomem *psc,
129 				       u16 prescaler, unsigned int divisor)
130 {
131 	/* select prescaler */
132 	out_be16(&psc->mpc52xx_psc_clock_select, prescaler);
133 	out_8(&psc->ctur, divisor >> 8);
134 	out_8(&psc->ctlr, divisor & 0xff);
135 }
136 
137 #ifdef CONFIG_PPC_MPC52xx
138 #define FIFO_52xx(port) ((struct mpc52xx_psc_fifo __iomem *)(PSC(port)+1))
139 static void mpc52xx_psc_fifo_init(struct uart_port *port)
140 {
141 	struct mpc52xx_psc __iomem *psc = PSC(port);
142 	struct mpc52xx_psc_fifo __iomem *fifo = FIFO_52xx(port);
143 
144 	out_8(&fifo->rfcntl, 0x00);
145 	out_be16(&fifo->rfalarm, 0x1ff);
146 	out_8(&fifo->tfcntl, 0x07);
147 	out_be16(&fifo->tfalarm, 0x80);
148 
149 	port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY;
150 	out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
151 }
152 
153 static int mpc52xx_psc_raw_rx_rdy(struct uart_port *port)
154 {
155 	return in_be16(&PSC(port)->mpc52xx_psc_status)
156 	    & MPC52xx_PSC_SR_RXRDY;
157 }
158 
159 static int mpc52xx_psc_raw_tx_rdy(struct uart_port *port)
160 {
161 	return in_be16(&PSC(port)->mpc52xx_psc_status)
162 	    & MPC52xx_PSC_SR_TXRDY;
163 }
164 
165 
166 static int mpc52xx_psc_rx_rdy(struct uart_port *port)
167 {
168 	return in_be16(&PSC(port)->mpc52xx_psc_isr)
169 	    & port->read_status_mask
170 	    & MPC52xx_PSC_IMR_RXRDY;
171 }
172 
173 static int mpc52xx_psc_tx_rdy(struct uart_port *port)
174 {
175 	return in_be16(&PSC(port)->mpc52xx_psc_isr)
176 	    & port->read_status_mask
177 	    & MPC52xx_PSC_IMR_TXRDY;
178 }
179 
180 static int mpc52xx_psc_tx_empty(struct uart_port *port)
181 {
182 	return in_be16(&PSC(port)->mpc52xx_psc_status)
183 	    & MPC52xx_PSC_SR_TXEMP;
184 }
185 
186 static void mpc52xx_psc_start_tx(struct uart_port *port)
187 {
188 	port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
189 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
190 }
191 
192 static void mpc52xx_psc_stop_tx(struct uart_port *port)
193 {
194 	port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY;
195 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
196 }
197 
198 static void mpc52xx_psc_stop_rx(struct uart_port *port)
199 {
200 	port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY;
201 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
202 }
203 
204 static void mpc52xx_psc_rx_clr_irq(struct uart_port *port)
205 {
206 }
207 
208 static void mpc52xx_psc_tx_clr_irq(struct uart_port *port)
209 {
210 }
211 
212 static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char c)
213 {
214 	out_8(&PSC(port)->mpc52xx_psc_buffer_8, c);
215 }
216 
217 static unsigned char mpc52xx_psc_read_char(struct uart_port *port)
218 {
219 	return in_8(&PSC(port)->mpc52xx_psc_buffer_8);
220 }
221 
222 static void mpc52xx_psc_cw_disable_ints(struct uart_port *port)
223 {
224 	out_be16(&PSC(port)->mpc52xx_psc_imr, 0);
225 }
226 
227 static void mpc52xx_psc_cw_restore_ints(struct uart_port *port)
228 {
229 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
230 }
231 
232 static unsigned int mpc5200_psc_set_baudrate(struct uart_port *port,
233 					     struct ktermios *new,
234 					     struct ktermios *old)
235 {
236 	unsigned int baud;
237 	unsigned int divisor;
238 
239 	/* The 5200 has a fixed /32 prescaler, uartclk contains the ipb freq */
240 	baud = uart_get_baud_rate(port, new, old,
241 				  port->uartclk / (32 * 0xffff) + 1,
242 				  port->uartclk / 32);
243 	divisor = (port->uartclk + 16 * baud) / (32 * baud);
244 
245 	/* enable the /32 prescaler and set the divisor */
246 	mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
247 	return baud;
248 }
249 
250 static unsigned int mpc5200b_psc_set_baudrate(struct uart_port *port,
251 					      struct ktermios *new,
252 					      struct ktermios *old)
253 {
254 	unsigned int baud;
255 	unsigned int divisor;
256 	u16 prescaler;
257 
258 	/* The 5200B has a selectable /4 or /32 prescaler, uartclk contains the
259 	 * ipb freq */
260 	baud = uart_get_baud_rate(port, new, old,
261 				  port->uartclk / (32 * 0xffff) + 1,
262 				  port->uartclk / 4);
263 	divisor = (port->uartclk + 2 * baud) / (4 * baud);
264 
265 	/* select the proper prescaler and set the divisor
266 	 * prefer high prescaler for more tolerance on low baudrates */
267 	if (divisor > 0xffff || baud <= 115200) {
268 		divisor = (divisor + 4) / 8;
269 		prescaler = 0xdd00; /* /32 */
270 	} else
271 		prescaler = 0xff00; /* /4 */
272 	mpc52xx_set_divisor(PSC(port), prescaler, divisor);
273 	return baud;
274 }
275 
276 static void mpc52xx_psc_get_irq(struct uart_port *port, struct device_node *np)
277 {
278 	port->irqflags = 0;
279 	port->irq = irq_of_parse_and_map(np, 0);
280 }
281 
282 /* 52xx specific interrupt handler. The caller holds the port lock */
283 static irqreturn_t mpc52xx_psc_handle_irq(struct uart_port *port)
284 {
285 	return mpc5xxx_uart_process_int(port);
286 }
287 
288 static struct psc_ops mpc52xx_psc_ops = {
289 	.fifo_init = mpc52xx_psc_fifo_init,
290 	.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
291 	.raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
292 	.rx_rdy = mpc52xx_psc_rx_rdy,
293 	.tx_rdy = mpc52xx_psc_tx_rdy,
294 	.tx_empty = mpc52xx_psc_tx_empty,
295 	.stop_rx = mpc52xx_psc_stop_rx,
296 	.start_tx = mpc52xx_psc_start_tx,
297 	.stop_tx = mpc52xx_psc_stop_tx,
298 	.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
299 	.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
300 	.write_char = mpc52xx_psc_write_char,
301 	.read_char = mpc52xx_psc_read_char,
302 	.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
303 	.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
304 	.set_baudrate = mpc5200_psc_set_baudrate,
305 	.get_irq = mpc52xx_psc_get_irq,
306 	.handle_irq = mpc52xx_psc_handle_irq,
307 };
308 
309 static struct psc_ops mpc5200b_psc_ops = {
310 	.fifo_init = mpc52xx_psc_fifo_init,
311 	.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
312 	.raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
313 	.rx_rdy = mpc52xx_psc_rx_rdy,
314 	.tx_rdy = mpc52xx_psc_tx_rdy,
315 	.tx_empty = mpc52xx_psc_tx_empty,
316 	.stop_rx = mpc52xx_psc_stop_rx,
317 	.start_tx = mpc52xx_psc_start_tx,
318 	.stop_tx = mpc52xx_psc_stop_tx,
319 	.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
320 	.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
321 	.write_char = mpc52xx_psc_write_char,
322 	.read_char = mpc52xx_psc_read_char,
323 	.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
324 	.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
325 	.set_baudrate = mpc5200b_psc_set_baudrate,
326 	.get_irq = mpc52xx_psc_get_irq,
327 	.handle_irq = mpc52xx_psc_handle_irq,
328 };
329 
330 #endif /* CONFIG_MPC52xx */
331 
332 #ifdef CONFIG_PPC_MPC512x
333 #define FIFO_512x(port) ((struct mpc512x_psc_fifo __iomem *)(PSC(port)+1))
334 
335 /* PSC FIFO Controller for mpc512x */
336 struct psc_fifoc {
337 	u32 fifoc_cmd;
338 	u32 fifoc_int;
339 	u32 fifoc_dma;
340 	u32 fifoc_axe;
341 	u32 fifoc_debug;
342 };
343 
344 static struct psc_fifoc __iomem *psc_fifoc;
345 static unsigned int psc_fifoc_irq;
346 
347 static void mpc512x_psc_fifo_init(struct uart_port *port)
348 {
349 	/* /32 prescaler */
350 	out_be16(&PSC(port)->mpc52xx_psc_clock_select, 0xdd00);
351 
352 	out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
353 	out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
354 	out_be32(&FIFO_512x(port)->txalarm, 1);
355 	out_be32(&FIFO_512x(port)->tximr, 0);
356 
357 	out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
358 	out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
359 	out_be32(&FIFO_512x(port)->rxalarm, 1);
360 	out_be32(&FIFO_512x(port)->rximr, 0);
361 
362 	out_be32(&FIFO_512x(port)->tximr, MPC512x_PSC_FIFO_ALARM);
363 	out_be32(&FIFO_512x(port)->rximr, MPC512x_PSC_FIFO_ALARM);
364 }
365 
366 static int mpc512x_psc_raw_rx_rdy(struct uart_port *port)
367 {
368 	return !(in_be32(&FIFO_512x(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
369 }
370 
371 static int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
372 {
373 	return !(in_be32(&FIFO_512x(port)->txsr) & MPC512x_PSC_FIFO_FULL);
374 }
375 
376 static int mpc512x_psc_rx_rdy(struct uart_port *port)
377 {
378 	return in_be32(&FIFO_512x(port)->rxsr)
379 	    & in_be32(&FIFO_512x(port)->rximr)
380 	    & MPC512x_PSC_FIFO_ALARM;
381 }
382 
383 static int mpc512x_psc_tx_rdy(struct uart_port *port)
384 {
385 	return in_be32(&FIFO_512x(port)->txsr)
386 	    & in_be32(&FIFO_512x(port)->tximr)
387 	    & MPC512x_PSC_FIFO_ALARM;
388 }
389 
390 static int mpc512x_psc_tx_empty(struct uart_port *port)
391 {
392 	return in_be32(&FIFO_512x(port)->txsr)
393 	    & MPC512x_PSC_FIFO_EMPTY;
394 }
395 
396 static void mpc512x_psc_stop_rx(struct uart_port *port)
397 {
398 	unsigned long rx_fifo_imr;
399 
400 	rx_fifo_imr = in_be32(&FIFO_512x(port)->rximr);
401 	rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
402 	out_be32(&FIFO_512x(port)->rximr, rx_fifo_imr);
403 }
404 
405 static void mpc512x_psc_start_tx(struct uart_port *port)
406 {
407 	unsigned long tx_fifo_imr;
408 
409 	tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
410 	tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
411 	out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
412 }
413 
414 static void mpc512x_psc_stop_tx(struct uart_port *port)
415 {
416 	unsigned long tx_fifo_imr;
417 
418 	tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
419 	tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
420 	out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
421 }
422 
423 static void mpc512x_psc_rx_clr_irq(struct uart_port *port)
424 {
425 	out_be32(&FIFO_512x(port)->rxisr, in_be32(&FIFO_512x(port)->rxisr));
426 }
427 
428 static void mpc512x_psc_tx_clr_irq(struct uart_port *port)
429 {
430 	out_be32(&FIFO_512x(port)->txisr, in_be32(&FIFO_512x(port)->txisr));
431 }
432 
433 static void mpc512x_psc_write_char(struct uart_port *port, unsigned char c)
434 {
435 	out_8(&FIFO_512x(port)->txdata_8, c);
436 }
437 
438 static unsigned char mpc512x_psc_read_char(struct uart_port *port)
439 {
440 	return in_8(&FIFO_512x(port)->rxdata_8);
441 }
442 
443 static void mpc512x_psc_cw_disable_ints(struct uart_port *port)
444 {
445 	port->read_status_mask =
446 		in_be32(&FIFO_512x(port)->tximr) << 16 |
447 		in_be32(&FIFO_512x(port)->rximr);
448 	out_be32(&FIFO_512x(port)->tximr, 0);
449 	out_be32(&FIFO_512x(port)->rximr, 0);
450 }
451 
452 static void mpc512x_psc_cw_restore_ints(struct uart_port *port)
453 {
454 	out_be32(&FIFO_512x(port)->tximr,
455 		(port->read_status_mask >> 16) & 0x7f);
456 	out_be32(&FIFO_512x(port)->rximr, port->read_status_mask & 0x7f);
457 }
458 
459 static unsigned int mpc512x_psc_set_baudrate(struct uart_port *port,
460 					     struct ktermios *new,
461 					     struct ktermios *old)
462 {
463 	unsigned int baud;
464 	unsigned int divisor;
465 
466 	/*
467 	 * The "MPC5121e Microcontroller Reference Manual, Rev. 3" says on
468 	 * pg. 30-10 that the chip supports a /32 and a /10 prescaler.
469 	 * Furthermore, it states that "After reset, the prescaler by 10
470 	 * for the UART mode is selected", but the reset register value is
471 	 * 0x0000 which means a /32 prescaler. This is wrong.
472 	 *
473 	 * In reality using /32 prescaler doesn't work, as it is not supported!
474 	 * Use /16 or /10 prescaler, see "MPC5121e Hardware Design Guide",
475 	 * Chapter 4.1 PSC in UART Mode.
476 	 * Calculate with a /16 prescaler here.
477 	 */
478 
479 	/* uartclk contains the ips freq */
480 	baud = uart_get_baud_rate(port, new, old,
481 				  port->uartclk / (16 * 0xffff) + 1,
482 				  port->uartclk / 16);
483 	divisor = (port->uartclk + 8 * baud) / (16 * baud);
484 
485 	/* enable the /16 prescaler and set the divisor */
486 	mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
487 	return baud;
488 }
489 
490 /* Init PSC FIFO Controller */
491 static int __init mpc512x_psc_fifoc_init(void)
492 {
493 	struct device_node *np;
494 
495 	np = of_find_compatible_node(NULL, NULL,
496 				     "fsl,mpc5121-psc-fifo");
497 	if (!np) {
498 		pr_err("%s: Can't find FIFOC node\n", __func__);
499 		return -ENODEV;
500 	}
501 
502 	psc_fifoc = of_iomap(np, 0);
503 	if (!psc_fifoc) {
504 		pr_err("%s: Can't map FIFOC\n", __func__);
505 		of_node_put(np);
506 		return -ENODEV;
507 	}
508 
509 	psc_fifoc_irq = irq_of_parse_and_map(np, 0);
510 	of_node_put(np);
511 	if (psc_fifoc_irq == 0) {
512 		pr_err("%s: Can't get FIFOC irq\n", __func__);
513 		iounmap(psc_fifoc);
514 		return -ENODEV;
515 	}
516 
517 	return 0;
518 }
519 
520 static void __exit mpc512x_psc_fifoc_uninit(void)
521 {
522 	iounmap(psc_fifoc);
523 }
524 
525 /* 512x specific interrupt handler. The caller holds the port lock */
526 static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port)
527 {
528 	unsigned long fifoc_int;
529 	int psc_num;
530 
531 	/* Read pending PSC FIFOC interrupts */
532 	fifoc_int = in_be32(&psc_fifoc->fifoc_int);
533 
534 	/* Check if it is an interrupt for this port */
535 	psc_num = (port->mapbase & 0xf00) >> 8;
536 	if (test_bit(psc_num, &fifoc_int) ||
537 	    test_bit(psc_num + 16, &fifoc_int))
538 		return mpc5xxx_uart_process_int(port);
539 
540 	return IRQ_NONE;
541 }
542 
543 static int mpc512x_psc_clock(struct uart_port *port, int enable)
544 {
545 	struct clk *psc_clk;
546 	int psc_num;
547 	char clk_name[10];
548 
549 	if (uart_console(port))
550 		return 0;
551 
552 	psc_num = (port->mapbase & 0xf00) >> 8;
553 	snprintf(clk_name, sizeof(clk_name), "psc%d_clk", psc_num);
554 	psc_clk = clk_get(port->dev, clk_name);
555 	if (IS_ERR(psc_clk)) {
556 		dev_err(port->dev, "Failed to get PSC clock entry!\n");
557 		return -ENODEV;
558 	}
559 
560 	dev_dbg(port->dev, "%s %sable\n", clk_name, enable ? "en" : "dis");
561 
562 	if (enable)
563 		clk_enable(psc_clk);
564 	else
565 		clk_disable(psc_clk);
566 
567 	return 0;
568 }
569 
570 static void mpc512x_psc_get_irq(struct uart_port *port, struct device_node *np)
571 {
572 	port->irqflags = IRQF_SHARED;
573 	port->irq = psc_fifoc_irq;
574 }
575 
576 static struct psc_ops mpc512x_psc_ops = {
577 	.fifo_init = mpc512x_psc_fifo_init,
578 	.raw_rx_rdy = mpc512x_psc_raw_rx_rdy,
579 	.raw_tx_rdy = mpc512x_psc_raw_tx_rdy,
580 	.rx_rdy = mpc512x_psc_rx_rdy,
581 	.tx_rdy = mpc512x_psc_tx_rdy,
582 	.tx_empty = mpc512x_psc_tx_empty,
583 	.stop_rx = mpc512x_psc_stop_rx,
584 	.start_tx = mpc512x_psc_start_tx,
585 	.stop_tx = mpc512x_psc_stop_tx,
586 	.rx_clr_irq = mpc512x_psc_rx_clr_irq,
587 	.tx_clr_irq = mpc512x_psc_tx_clr_irq,
588 	.write_char = mpc512x_psc_write_char,
589 	.read_char = mpc512x_psc_read_char,
590 	.cw_disable_ints = mpc512x_psc_cw_disable_ints,
591 	.cw_restore_ints = mpc512x_psc_cw_restore_ints,
592 	.set_baudrate = mpc512x_psc_set_baudrate,
593 	.clock = mpc512x_psc_clock,
594 	.fifoc_init = mpc512x_psc_fifoc_init,
595 	.fifoc_uninit = mpc512x_psc_fifoc_uninit,
596 	.get_irq = mpc512x_psc_get_irq,
597 	.handle_irq = mpc512x_psc_handle_irq,
598 };
599 #endif
600 
601 static const struct psc_ops *psc_ops;
602 
603 /* ======================================================================== */
604 /* UART operations                                                          */
605 /* ======================================================================== */
606 
607 static unsigned int
608 mpc52xx_uart_tx_empty(struct uart_port *port)
609 {
610 	return psc_ops->tx_empty(port) ? TIOCSER_TEMT : 0;
611 }
612 
613 static void
614 mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
615 {
616 	if (mctrl & TIOCM_RTS)
617 		out_8(&PSC(port)->op1, MPC52xx_PSC_OP_RTS);
618 	else
619 		out_8(&PSC(port)->op0, MPC52xx_PSC_OP_RTS);
620 }
621 
622 static unsigned int
623 mpc52xx_uart_get_mctrl(struct uart_port *port)
624 {
625 	unsigned int ret = TIOCM_DSR;
626 	u8 status = in_8(&PSC(port)->mpc52xx_psc_ipcr);
627 
628 	if (!(status & MPC52xx_PSC_CTS))
629 		ret |= TIOCM_CTS;
630 	if (!(status & MPC52xx_PSC_DCD))
631 		ret |= TIOCM_CAR;
632 
633 	return ret;
634 }
635 
636 static void
637 mpc52xx_uart_stop_tx(struct uart_port *port)
638 {
639 	/* port->lock taken by caller */
640 	psc_ops->stop_tx(port);
641 }
642 
643 static void
644 mpc52xx_uart_start_tx(struct uart_port *port)
645 {
646 	/* port->lock taken by caller */
647 	psc_ops->start_tx(port);
648 }
649 
650 static void
651 mpc52xx_uart_send_xchar(struct uart_port *port, char ch)
652 {
653 	unsigned long flags;
654 	spin_lock_irqsave(&port->lock, flags);
655 
656 	port->x_char = ch;
657 	if (ch) {
658 		/* Make sure tx interrupts are on */
659 		/* Truly necessary ??? They should be anyway */
660 		psc_ops->start_tx(port);
661 	}
662 
663 	spin_unlock_irqrestore(&port->lock, flags);
664 }
665 
666 static void
667 mpc52xx_uart_stop_rx(struct uart_port *port)
668 {
669 	/* port->lock taken by caller */
670 	psc_ops->stop_rx(port);
671 }
672 
673 static void
674 mpc52xx_uart_enable_ms(struct uart_port *port)
675 {
676 	struct mpc52xx_psc __iomem *psc = PSC(port);
677 
678 	/* clear D_*-bits by reading them */
679 	in_8(&psc->mpc52xx_psc_ipcr);
680 	/* enable CTS and DCD as IPC interrupts */
681 	out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD);
682 
683 	port->read_status_mask |= MPC52xx_PSC_IMR_IPC;
684 	out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
685 }
686 
687 static void
688 mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
689 {
690 	unsigned long flags;
691 	spin_lock_irqsave(&port->lock, flags);
692 
693 	if (ctl == -1)
694 		out_8(&PSC(port)->command, MPC52xx_PSC_START_BRK);
695 	else
696 		out_8(&PSC(port)->command, MPC52xx_PSC_STOP_BRK);
697 
698 	spin_unlock_irqrestore(&port->lock, flags);
699 }
700 
701 static int
702 mpc52xx_uart_startup(struct uart_port *port)
703 {
704 	struct mpc52xx_psc __iomem *psc = PSC(port);
705 	int ret;
706 
707 	if (psc_ops->clock) {
708 		ret = psc_ops->clock(port, 1);
709 		if (ret)
710 			return ret;
711 	}
712 
713 	/* Request IRQ */
714 	ret = request_irq(port->irq, mpc52xx_uart_int,
715 			  port->irqflags, "mpc52xx_psc_uart", port);
716 	if (ret)
717 		return ret;
718 
719 	/* Reset/activate the port, clear and enable interrupts */
720 	out_8(&psc->command, MPC52xx_PSC_RST_RX);
721 	out_8(&psc->command, MPC52xx_PSC_RST_TX);
722 
723 	out_be32(&psc->sicr, 0);	/* UART mode DCD ignored */
724 
725 	psc_ops->fifo_init(port);
726 
727 	out_8(&psc->command, MPC52xx_PSC_TX_ENABLE);
728 	out_8(&psc->command, MPC52xx_PSC_RX_ENABLE);
729 
730 	return 0;
731 }
732 
733 static void
734 mpc52xx_uart_shutdown(struct uart_port *port)
735 {
736 	struct mpc52xx_psc __iomem *psc = PSC(port);
737 
738 	/* Shut down the port.  Leave TX active if on a console port */
739 	out_8(&psc->command, MPC52xx_PSC_RST_RX);
740 	if (!uart_console(port))
741 		out_8(&psc->command, MPC52xx_PSC_RST_TX);
742 
743 	port->read_status_mask = 0;
744 	out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
745 
746 	if (psc_ops->clock)
747 		psc_ops->clock(port, 0);
748 
749 	/* Release interrupt */
750 	free_irq(port->irq, port);
751 }
752 
753 static void
754 mpc52xx_uart_set_termios(struct uart_port *port, struct ktermios *new,
755 			 struct ktermios *old)
756 {
757 	struct mpc52xx_psc __iomem *psc = PSC(port);
758 	unsigned long flags;
759 	unsigned char mr1, mr2;
760 	unsigned int j;
761 	unsigned int baud;
762 
763 	/* Prepare what we're gonna write */
764 	mr1 = 0;
765 
766 	switch (new->c_cflag & CSIZE) {
767 	case CS5:	mr1 |= MPC52xx_PSC_MODE_5_BITS;
768 		break;
769 	case CS6:	mr1 |= MPC52xx_PSC_MODE_6_BITS;
770 		break;
771 	case CS7:	mr1 |= MPC52xx_PSC_MODE_7_BITS;
772 		break;
773 	case CS8:
774 	default:	mr1 |= MPC52xx_PSC_MODE_8_BITS;
775 	}
776 
777 	if (new->c_cflag & PARENB) {
778 		if (new->c_cflag & CMSPAR)
779 			mr1 |= MPC52xx_PSC_MODE_PARFORCE;
780 
781 		/* With CMSPAR, PARODD also means high parity (same as termios) */
782 		mr1 |= (new->c_cflag & PARODD) ?
783 			MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
784 	} else {
785 		mr1 |= MPC52xx_PSC_MODE_PARNONE;
786 	}
787 
788 	mr2 = 0;
789 
790 	if (new->c_cflag & CSTOPB)
791 		mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
792 	else
793 		mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
794 			MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
795 			MPC52xx_PSC_MODE_ONE_STOP;
796 
797 	if (new->c_cflag & CRTSCTS) {
798 		mr1 |= MPC52xx_PSC_MODE_RXRTS;
799 		mr2 |= MPC52xx_PSC_MODE_TXCTS;
800 	}
801 
802 	/* Get the lock */
803 	spin_lock_irqsave(&port->lock, flags);
804 
805 	/* Do our best to flush TX & RX, so we don't lose anything */
806 	/* But we don't wait indefinitely ! */
807 	j = 5000000;	/* Maximum wait */
808 	/* FIXME Can't receive chars since set_termios might be called at early
809 	 * boot for the console, all stuff is not yet ready to receive at that
810 	 * time and that just makes the kernel oops */
811 	/* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
812 	while (!mpc52xx_uart_tx_empty(port) && --j)
813 		udelay(1);
814 
815 	if (!j)
816 		printk(KERN_ERR "mpc52xx_uart.c: "
817 			"Unable to flush RX & TX fifos in-time in set_termios."
818 			"Some chars may have been lost.\n");
819 
820 	/* Reset the TX & RX */
821 	out_8(&psc->command, MPC52xx_PSC_RST_RX);
822 	out_8(&psc->command, MPC52xx_PSC_RST_TX);
823 
824 	/* Send new mode settings */
825 	out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
826 	out_8(&psc->mode, mr1);
827 	out_8(&psc->mode, mr2);
828 	baud = psc_ops->set_baudrate(port, new, old);
829 
830 	/* Update the per-port timeout */
831 	uart_update_timeout(port, new->c_cflag, baud);
832 
833 	if (UART_ENABLE_MS(port, new->c_cflag))
834 		mpc52xx_uart_enable_ms(port);
835 
836 	/* Reenable TX & RX */
837 	out_8(&psc->command, MPC52xx_PSC_TX_ENABLE);
838 	out_8(&psc->command, MPC52xx_PSC_RX_ENABLE);
839 
840 	/* We're all set, release the lock */
841 	spin_unlock_irqrestore(&port->lock, flags);
842 }
843 
844 static const char *
845 mpc52xx_uart_type(struct uart_port *port)
846 {
847 	/*
848 	 * We keep using PORT_MPC52xx for historic reasons although it applies
849 	 * for MPC512x, too, but print "MPC5xxx" to not irritate users
850 	 */
851 	return port->type == PORT_MPC52xx ? "MPC5xxx PSC" : NULL;
852 }
853 
854 static void
855 mpc52xx_uart_release_port(struct uart_port *port)
856 {
857 	/* remapped by us ? */
858 	if (port->flags & UPF_IOREMAP) {
859 		iounmap(port->membase);
860 		port->membase = NULL;
861 	}
862 
863 	release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
864 }
865 
866 static int
867 mpc52xx_uart_request_port(struct uart_port *port)
868 {
869 	int err;
870 
871 	if (port->flags & UPF_IOREMAP) /* Need to remap ? */
872 		port->membase = ioremap(port->mapbase,
873 					sizeof(struct mpc52xx_psc));
874 
875 	if (!port->membase)
876 		return -EINVAL;
877 
878 	err = request_mem_region(port->mapbase, sizeof(struct mpc52xx_psc),
879 			"mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
880 
881 	if (err && (port->flags & UPF_IOREMAP)) {
882 		iounmap(port->membase);
883 		port->membase = NULL;
884 	}
885 
886 	return err;
887 }
888 
889 static void
890 mpc52xx_uart_config_port(struct uart_port *port, int flags)
891 {
892 	if ((flags & UART_CONFIG_TYPE)
893 		&& (mpc52xx_uart_request_port(port) == 0))
894 		port->type = PORT_MPC52xx;
895 }
896 
897 static int
898 mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
899 {
900 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx)
901 		return -EINVAL;
902 
903 	if ((ser->irq != port->irq) ||
904 	    (ser->io_type != UPIO_MEM) ||
905 	    (ser->baud_base != port->uartclk)  ||
906 	    (ser->iomem_base != (void *)port->mapbase) ||
907 	    (ser->hub6 != 0))
908 		return -EINVAL;
909 
910 	return 0;
911 }
912 
913 
914 static struct uart_ops mpc52xx_uart_ops = {
915 	.tx_empty	= mpc52xx_uart_tx_empty,
916 	.set_mctrl	= mpc52xx_uart_set_mctrl,
917 	.get_mctrl	= mpc52xx_uart_get_mctrl,
918 	.stop_tx	= mpc52xx_uart_stop_tx,
919 	.start_tx	= mpc52xx_uart_start_tx,
920 	.send_xchar	= mpc52xx_uart_send_xchar,
921 	.stop_rx	= mpc52xx_uart_stop_rx,
922 	.enable_ms	= mpc52xx_uart_enable_ms,
923 	.break_ctl	= mpc52xx_uart_break_ctl,
924 	.startup	= mpc52xx_uart_startup,
925 	.shutdown	= mpc52xx_uart_shutdown,
926 	.set_termios	= mpc52xx_uart_set_termios,
927 /*	.pm		= mpc52xx_uart_pm,		Not supported yet */
928 /*	.set_wake	= mpc52xx_uart_set_wake,	Not supported yet */
929 	.type		= mpc52xx_uart_type,
930 	.release_port	= mpc52xx_uart_release_port,
931 	.request_port	= mpc52xx_uart_request_port,
932 	.config_port	= mpc52xx_uart_config_port,
933 	.verify_port	= mpc52xx_uart_verify_port
934 };
935 
936 
937 /* ======================================================================== */
938 /* Interrupt handling                                                       */
939 /* ======================================================================== */
940 
941 static inline int
942 mpc52xx_uart_int_rx_chars(struct uart_port *port)
943 {
944 	struct tty_struct *tty = port->state->port.tty;
945 	unsigned char ch, flag;
946 	unsigned short status;
947 
948 	/* While we can read, do so ! */
949 	while (psc_ops->raw_rx_rdy(port)) {
950 		/* Get the char */
951 		ch = psc_ops->read_char(port);
952 
953 		/* Handle sysreq char */
954 #ifdef SUPPORT_SYSRQ
955 		if (uart_handle_sysrq_char(port, ch)) {
956 			port->sysrq = 0;
957 			continue;
958 		}
959 #endif
960 
961 		/* Store it */
962 
963 		flag = TTY_NORMAL;
964 		port->icount.rx++;
965 
966 		status = in_be16(&PSC(port)->mpc52xx_psc_status);
967 
968 		if (status & (MPC52xx_PSC_SR_PE |
969 			      MPC52xx_PSC_SR_FE |
970 			      MPC52xx_PSC_SR_RB)) {
971 
972 			if (status & MPC52xx_PSC_SR_RB) {
973 				flag = TTY_BREAK;
974 				uart_handle_break(port);
975 				port->icount.brk++;
976 			} else if (status & MPC52xx_PSC_SR_PE) {
977 				flag = TTY_PARITY;
978 				port->icount.parity++;
979 			}
980 			else if (status & MPC52xx_PSC_SR_FE) {
981 				flag = TTY_FRAME;
982 				port->icount.frame++;
983 			}
984 
985 			/* Clear error condition */
986 			out_8(&PSC(port)->command, MPC52xx_PSC_RST_ERR_STAT);
987 
988 		}
989 		tty_insert_flip_char(tty, ch, flag);
990 		if (status & MPC52xx_PSC_SR_OE) {
991 			/*
992 			 * Overrun is special, since it's
993 			 * reported immediately, and doesn't
994 			 * affect the current character
995 			 */
996 			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
997 			port->icount.overrun++;
998 		}
999 	}
1000 
1001 	spin_unlock(&port->lock);
1002 	tty_flip_buffer_push(tty);
1003 	spin_lock(&port->lock);
1004 
1005 	return psc_ops->raw_rx_rdy(port);
1006 }
1007 
1008 static inline int
1009 mpc52xx_uart_int_tx_chars(struct uart_port *port)
1010 {
1011 	struct circ_buf *xmit = &port->state->xmit;
1012 
1013 	/* Process out of band chars */
1014 	if (port->x_char) {
1015 		psc_ops->write_char(port, port->x_char);
1016 		port->icount.tx++;
1017 		port->x_char = 0;
1018 		return 1;
1019 	}
1020 
1021 	/* Nothing to do ? */
1022 	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
1023 		mpc52xx_uart_stop_tx(port);
1024 		return 0;
1025 	}
1026 
1027 	/* Send chars */
1028 	while (psc_ops->raw_tx_rdy(port)) {
1029 		psc_ops->write_char(port, xmit->buf[xmit->tail]);
1030 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
1031 		port->icount.tx++;
1032 		if (uart_circ_empty(xmit))
1033 			break;
1034 	}
1035 
1036 	/* Wake up */
1037 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1038 		uart_write_wakeup(port);
1039 
1040 	/* Maybe we're done after all */
1041 	if (uart_circ_empty(xmit)) {
1042 		mpc52xx_uart_stop_tx(port);
1043 		return 0;
1044 	}
1045 
1046 	return 1;
1047 }
1048 
1049 static irqreturn_t
1050 mpc5xxx_uart_process_int(struct uart_port *port)
1051 {
1052 	unsigned long pass = ISR_PASS_LIMIT;
1053 	unsigned int keepgoing;
1054 	u8 status;
1055 
1056 	/* While we have stuff to do, we continue */
1057 	do {
1058 		/* If we don't find anything to do, we stop */
1059 		keepgoing = 0;
1060 
1061 		psc_ops->rx_clr_irq(port);
1062 		if (psc_ops->rx_rdy(port))
1063 			keepgoing |= mpc52xx_uart_int_rx_chars(port);
1064 
1065 		psc_ops->tx_clr_irq(port);
1066 		if (psc_ops->tx_rdy(port))
1067 			keepgoing |= mpc52xx_uart_int_tx_chars(port);
1068 
1069 		status = in_8(&PSC(port)->mpc52xx_psc_ipcr);
1070 		if (status & MPC52xx_PSC_D_DCD)
1071 			uart_handle_dcd_change(port, !(status & MPC52xx_PSC_DCD));
1072 
1073 		if (status & MPC52xx_PSC_D_CTS)
1074 			uart_handle_cts_change(port, !(status & MPC52xx_PSC_CTS));
1075 
1076 		/* Limit number of iteration */
1077 		if (!(--pass))
1078 			keepgoing = 0;
1079 
1080 	} while (keepgoing);
1081 
1082 	return IRQ_HANDLED;
1083 }
1084 
1085 static irqreturn_t
1086 mpc52xx_uart_int(int irq, void *dev_id)
1087 {
1088 	struct uart_port *port = dev_id;
1089 	irqreturn_t ret;
1090 
1091 	spin_lock(&port->lock);
1092 
1093 	ret = psc_ops->handle_irq(port);
1094 
1095 	spin_unlock(&port->lock);
1096 
1097 	return ret;
1098 }
1099 
1100 /* ======================================================================== */
1101 /* Console ( if applicable )                                                */
1102 /* ======================================================================== */
1103 
1104 #ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
1105 
1106 static void __init
1107 mpc52xx_console_get_options(struct uart_port *port,
1108 			    int *baud, int *parity, int *bits, int *flow)
1109 {
1110 	struct mpc52xx_psc __iomem *psc = PSC(port);
1111 	unsigned char mr1;
1112 
1113 	pr_debug("mpc52xx_console_get_options(port=%p)\n", port);
1114 
1115 	/* Read the mode registers */
1116 	out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
1117 	mr1 = in_8(&psc->mode);
1118 
1119 	/* CT{U,L}R are write-only ! */
1120 	*baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1121 
1122 	/* Parse them */
1123 	switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
1124 	case MPC52xx_PSC_MODE_5_BITS:
1125 		*bits = 5;
1126 		break;
1127 	case MPC52xx_PSC_MODE_6_BITS:
1128 		*bits = 6;
1129 		break;
1130 	case MPC52xx_PSC_MODE_7_BITS:
1131 		*bits = 7;
1132 		break;
1133 	case MPC52xx_PSC_MODE_8_BITS:
1134 	default:
1135 		*bits = 8;
1136 	}
1137 
1138 	if (mr1 & MPC52xx_PSC_MODE_PARNONE)
1139 		*parity = 'n';
1140 	else
1141 		*parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
1142 }
1143 
1144 static void
1145 mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
1146 {
1147 	struct uart_port *port = &mpc52xx_uart_ports[co->index];
1148 	unsigned int i, j;
1149 
1150 	/* Disable interrupts */
1151 	psc_ops->cw_disable_ints(port);
1152 
1153 	/* Wait the TX buffer to be empty */
1154 	j = 5000000;	/* Maximum wait */
1155 	while (!mpc52xx_uart_tx_empty(port) && --j)
1156 		udelay(1);
1157 
1158 	/* Write all the chars */
1159 	for (i = 0; i < count; i++, s++) {
1160 		/* Line return handling */
1161 		if (*s == '\n')
1162 			psc_ops->write_char(port, '\r');
1163 
1164 		/* Send the char */
1165 		psc_ops->write_char(port, *s);
1166 
1167 		/* Wait the TX buffer to be empty */
1168 		j = 20000;	/* Maximum wait */
1169 		while (!mpc52xx_uart_tx_empty(port) && --j)
1170 			udelay(1);
1171 	}
1172 
1173 	/* Restore interrupt state */
1174 	psc_ops->cw_restore_ints(port);
1175 }
1176 
1177 
1178 static int __init
1179 mpc52xx_console_setup(struct console *co, char *options)
1180 {
1181 	struct uart_port *port = &mpc52xx_uart_ports[co->index];
1182 	struct device_node *np = mpc52xx_uart_nodes[co->index];
1183 	unsigned int uartclk;
1184 	struct resource res;
1185 	int ret;
1186 
1187 	int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1188 	int bits = 8;
1189 	int parity = 'n';
1190 	int flow = 'n';
1191 
1192 	pr_debug("mpc52xx_console_setup co=%p, co->index=%i, options=%s\n",
1193 		 co, co->index, options);
1194 
1195 	if ((co->index < 0) || (co->index >= MPC52xx_PSC_MAXNUM)) {
1196 		pr_debug("PSC%x out of range\n", co->index);
1197 		return -EINVAL;
1198 	}
1199 
1200 	if (!np) {
1201 		pr_debug("PSC%x not found in device tree\n", co->index);
1202 		return -EINVAL;
1203 	}
1204 
1205 	pr_debug("Console on ttyPSC%x is %s\n",
1206 		 co->index, mpc52xx_uart_nodes[co->index]->full_name);
1207 
1208 	/* Fetch register locations */
1209 	ret = of_address_to_resource(np, 0, &res);
1210 	if (ret) {
1211 		pr_debug("Could not get resources for PSC%x\n", co->index);
1212 		return ret;
1213 	}
1214 
1215 	uartclk = mpc5xxx_get_bus_frequency(np);
1216 	if (uartclk == 0) {
1217 		pr_debug("Could not find uart clock frequency!\n");
1218 		return -EINVAL;
1219 	}
1220 
1221 	/* Basic port init. Needed since we use some uart_??? func before
1222 	 * real init for early access */
1223 	spin_lock_init(&port->lock);
1224 	port->uartclk = uartclk;
1225 	port->ops	= &mpc52xx_uart_ops;
1226 	port->mapbase = res.start;
1227 	port->membase = ioremap(res.start, sizeof(struct mpc52xx_psc));
1228 	port->irq = irq_of_parse_and_map(np, 0);
1229 
1230 	if (port->membase == NULL)
1231 		return -EINVAL;
1232 
1233 	pr_debug("mpc52xx-psc uart at %p, mapped to %p, irq=%x, freq=%i\n",
1234 		 (void *)port->mapbase, port->membase,
1235 		 port->irq, port->uartclk);
1236 
1237 	/* Setup the port parameters accoding to options */
1238 	if (options)
1239 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1240 	else
1241 		mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
1242 
1243 	pr_debug("Setting console parameters: %i %i%c1 flow=%c\n",
1244 		 baud, bits, parity, flow);
1245 
1246 	return uart_set_options(port, co, baud, parity, bits, flow);
1247 }
1248 
1249 
1250 static struct uart_driver mpc52xx_uart_driver;
1251 
1252 static struct console mpc52xx_console = {
1253 	.name	= "ttyPSC",
1254 	.write	= mpc52xx_console_write,
1255 	.device	= uart_console_device,
1256 	.setup	= mpc52xx_console_setup,
1257 	.flags	= CON_PRINTBUFFER,
1258 	.index	= -1,	/* Specified on the cmdline (e.g. console=ttyPSC0) */
1259 	.data	= &mpc52xx_uart_driver,
1260 };
1261 
1262 
1263 static int __init
1264 mpc52xx_console_init(void)
1265 {
1266 	mpc52xx_uart_of_enumerate();
1267 	register_console(&mpc52xx_console);
1268 	return 0;
1269 }
1270 
1271 console_initcall(mpc52xx_console_init);
1272 
1273 #define MPC52xx_PSC_CONSOLE &mpc52xx_console
1274 #else
1275 #define MPC52xx_PSC_CONSOLE NULL
1276 #endif
1277 
1278 
1279 /* ======================================================================== */
1280 /* UART Driver                                                              */
1281 /* ======================================================================== */
1282 
1283 static struct uart_driver mpc52xx_uart_driver = {
1284 	.driver_name	= "mpc52xx_psc_uart",
1285 	.dev_name	= "ttyPSC",
1286 	.major		= SERIAL_PSC_MAJOR,
1287 	.minor		= SERIAL_PSC_MINOR,
1288 	.nr		= MPC52xx_PSC_MAXNUM,
1289 	.cons		= MPC52xx_PSC_CONSOLE,
1290 };
1291 
1292 /* ======================================================================== */
1293 /* OF Platform Driver                                                       */
1294 /* ======================================================================== */
1295 
1296 static struct of_device_id mpc52xx_uart_of_match[] = {
1297 #ifdef CONFIG_PPC_MPC52xx
1298 	{ .compatible = "fsl,mpc5200b-psc-uart", .data = &mpc5200b_psc_ops, },
1299 	{ .compatible = "fsl,mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1300 	/* binding used by old lite5200 device trees: */
1301 	{ .compatible = "mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1302 	/* binding used by efika: */
1303 	{ .compatible = "mpc5200-serial", .data = &mpc52xx_psc_ops, },
1304 #endif
1305 #ifdef CONFIG_PPC_MPC512x
1306 	{ .compatible = "fsl,mpc5121-psc-uart", .data = &mpc512x_psc_ops, },
1307 #endif
1308 	{},
1309 };
1310 
1311 static int mpc52xx_uart_of_probe(struct platform_device *op)
1312 {
1313 	int idx = -1;
1314 	unsigned int uartclk;
1315 	struct uart_port *port = NULL;
1316 	struct resource res;
1317 	int ret;
1318 
1319 	/* Check validity & presence */
1320 	for (idx = 0; idx < MPC52xx_PSC_MAXNUM; idx++)
1321 		if (mpc52xx_uart_nodes[idx] == op->dev.of_node)
1322 			break;
1323 	if (idx >= MPC52xx_PSC_MAXNUM)
1324 		return -EINVAL;
1325 	pr_debug("Found %s assigned to ttyPSC%x\n",
1326 		 mpc52xx_uart_nodes[idx]->full_name, idx);
1327 
1328 	/* set the uart clock to the input clock of the psc, the different
1329 	 * prescalers are taken into account in the set_baudrate() methods
1330 	 * of the respective chip */
1331 	uartclk = mpc5xxx_get_bus_frequency(op->dev.of_node);
1332 	if (uartclk == 0) {
1333 		dev_dbg(&op->dev, "Could not find uart clock frequency!\n");
1334 		return -EINVAL;
1335 	}
1336 
1337 	/* Init the port structure */
1338 	port = &mpc52xx_uart_ports[idx];
1339 
1340 	spin_lock_init(&port->lock);
1341 	port->uartclk = uartclk;
1342 	port->fifosize	= 512;
1343 	port->iotype	= UPIO_MEM;
1344 	port->flags	= UPF_BOOT_AUTOCONF |
1345 			  (uart_console(port) ? 0 : UPF_IOREMAP);
1346 	port->line	= idx;
1347 	port->ops	= &mpc52xx_uart_ops;
1348 	port->dev	= &op->dev;
1349 
1350 	/* Search for IRQ and mapbase */
1351 	ret = of_address_to_resource(op->dev.of_node, 0, &res);
1352 	if (ret)
1353 		return ret;
1354 
1355 	port->mapbase = res.start;
1356 	if (!port->mapbase) {
1357 		dev_dbg(&op->dev, "Could not allocate resources for PSC\n");
1358 		return -EINVAL;
1359 	}
1360 
1361 	psc_ops->get_irq(port, op->dev.of_node);
1362 	if (port->irq == 0) {
1363 		dev_dbg(&op->dev, "Could not get irq\n");
1364 		return -EINVAL;
1365 	}
1366 
1367 	dev_dbg(&op->dev, "mpc52xx-psc uart at %p, irq=%x, freq=%i\n",
1368 		(void *)port->mapbase, port->irq, port->uartclk);
1369 
1370 	/* Add the port to the uart sub-system */
1371 	ret = uart_add_one_port(&mpc52xx_uart_driver, port);
1372 	if (ret)
1373 		return ret;
1374 
1375 	dev_set_drvdata(&op->dev, (void *)port);
1376 	return 0;
1377 }
1378 
1379 static int
1380 mpc52xx_uart_of_remove(struct platform_device *op)
1381 {
1382 	struct uart_port *port = dev_get_drvdata(&op->dev);
1383 	dev_set_drvdata(&op->dev, NULL);
1384 
1385 	if (port)
1386 		uart_remove_one_port(&mpc52xx_uart_driver, port);
1387 
1388 	return 0;
1389 }
1390 
1391 #ifdef CONFIG_PM
1392 static int
1393 mpc52xx_uart_of_suspend(struct platform_device *op, pm_message_t state)
1394 {
1395 	struct uart_port *port = (struct uart_port *) dev_get_drvdata(&op->dev);
1396 
1397 	if (port)
1398 		uart_suspend_port(&mpc52xx_uart_driver, port);
1399 
1400 	return 0;
1401 }
1402 
1403 static int
1404 mpc52xx_uart_of_resume(struct platform_device *op)
1405 {
1406 	struct uart_port *port = (struct uart_port *) dev_get_drvdata(&op->dev);
1407 
1408 	if (port)
1409 		uart_resume_port(&mpc52xx_uart_driver, port);
1410 
1411 	return 0;
1412 }
1413 #endif
1414 
1415 static void
1416 mpc52xx_uart_of_assign(struct device_node *np)
1417 {
1418 	int i;
1419 
1420 	/* Find the first free PSC number */
1421 	for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1422 		if (mpc52xx_uart_nodes[i] == NULL) {
1423 			of_node_get(np);
1424 			mpc52xx_uart_nodes[i] = np;
1425 			return;
1426 		}
1427 	}
1428 }
1429 
1430 static void
1431 mpc52xx_uart_of_enumerate(void)
1432 {
1433 	static int enum_done;
1434 	struct device_node *np;
1435 	const struct  of_device_id *match;
1436 	int i;
1437 
1438 	if (enum_done)
1439 		return;
1440 
1441 	/* Assign index to each PSC in device tree */
1442 	for_each_matching_node(np, mpc52xx_uart_of_match) {
1443 		match = of_match_node(mpc52xx_uart_of_match, np);
1444 		psc_ops = match->data;
1445 		mpc52xx_uart_of_assign(np);
1446 	}
1447 
1448 	enum_done = 1;
1449 
1450 	for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1451 		if (mpc52xx_uart_nodes[i])
1452 			pr_debug("%s assigned to ttyPSC%x\n",
1453 				 mpc52xx_uart_nodes[i]->full_name, i);
1454 	}
1455 }
1456 
1457 MODULE_DEVICE_TABLE(of, mpc52xx_uart_of_match);
1458 
1459 static struct platform_driver mpc52xx_uart_of_driver = {
1460 	.probe		= mpc52xx_uart_of_probe,
1461 	.remove		= mpc52xx_uart_of_remove,
1462 #ifdef CONFIG_PM
1463 	.suspend	= mpc52xx_uart_of_suspend,
1464 	.resume		= mpc52xx_uart_of_resume,
1465 #endif
1466 	.driver = {
1467 		.name = "mpc52xx-psc-uart",
1468 		.owner = THIS_MODULE,
1469 		.of_match_table = mpc52xx_uart_of_match,
1470 	},
1471 };
1472 
1473 
1474 /* ======================================================================== */
1475 /* Module                                                                   */
1476 /* ======================================================================== */
1477 
1478 static int __init
1479 mpc52xx_uart_init(void)
1480 {
1481 	int ret;
1482 
1483 	printk(KERN_INFO "Serial: MPC52xx PSC UART driver\n");
1484 
1485 	ret = uart_register_driver(&mpc52xx_uart_driver);
1486 	if (ret) {
1487 		printk(KERN_ERR "%s: uart_register_driver failed (%i)\n",
1488 		       __FILE__, ret);
1489 		return ret;
1490 	}
1491 
1492 	mpc52xx_uart_of_enumerate();
1493 
1494 	/*
1495 	 * Map the PSC FIFO Controller and init if on MPC512x.
1496 	 */
1497 	if (psc_ops && psc_ops->fifoc_init) {
1498 		ret = psc_ops->fifoc_init();
1499 		if (ret)
1500 			return ret;
1501 	}
1502 
1503 	ret = platform_driver_register(&mpc52xx_uart_of_driver);
1504 	if (ret) {
1505 		printk(KERN_ERR "%s: platform_driver_register failed (%i)\n",
1506 		       __FILE__, ret);
1507 		uart_unregister_driver(&mpc52xx_uart_driver);
1508 		return ret;
1509 	}
1510 
1511 	return 0;
1512 }
1513 
1514 static void __exit
1515 mpc52xx_uart_exit(void)
1516 {
1517 	if (psc_ops->fifoc_uninit)
1518 		psc_ops->fifoc_uninit();
1519 
1520 	platform_driver_unregister(&mpc52xx_uart_of_driver);
1521 	uart_unregister_driver(&mpc52xx_uart_driver);
1522 }
1523 
1524 
1525 module_init(mpc52xx_uart_init);
1526 module_exit(mpc52xx_uart_exit);
1527 
1528 MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
1529 MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
1530 MODULE_LICENSE("GPL");
1531