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 /* PSC fifo operations for isolating differences between 52xx and 512x      */
89 /* ======================================================================== */
90 
91 struct psc_ops {
92 	void		(*fifo_init)(struct uart_port *port);
93 	int		(*raw_rx_rdy)(struct uart_port *port);
94 	int		(*raw_tx_rdy)(struct uart_port *port);
95 	int		(*rx_rdy)(struct uart_port *port);
96 	int		(*tx_rdy)(struct uart_port *port);
97 	int		(*tx_empty)(struct uart_port *port);
98 	void		(*stop_rx)(struct uart_port *port);
99 	void		(*start_tx)(struct uart_port *port);
100 	void		(*stop_tx)(struct uart_port *port);
101 	void		(*rx_clr_irq)(struct uart_port *port);
102 	void		(*tx_clr_irq)(struct uart_port *port);
103 	void		(*write_char)(struct uart_port *port, unsigned char c);
104 	unsigned char	(*read_char)(struct uart_port *port);
105 	void		(*cw_disable_ints)(struct uart_port *port);
106 	void		(*cw_restore_ints)(struct uart_port *port);
107 	unsigned int	(*set_baudrate)(struct uart_port *port,
108 					struct ktermios *new,
109 					struct ktermios *old);
110 	int		(*clock_alloc)(struct uart_port *port);
111 	void		(*clock_relse)(struct uart_port *port);
112 	int		(*clock)(struct uart_port *port, int enable);
113 	int		(*fifoc_init)(void);
114 	void		(*fifoc_uninit)(void);
115 	void		(*get_irq)(struct uart_port *, struct device_node *);
116 	irqreturn_t	(*handle_irq)(struct uart_port *port);
117 	u16		(*get_status)(struct uart_port *port);
118 	u8		(*get_ipcr)(struct uart_port *port);
119 	void		(*command)(struct uart_port *port, u8 cmd);
120 	void		(*set_mode)(struct uart_port *port, u8 mr1, u8 mr2);
121 	void		(*set_rts)(struct uart_port *port, int state);
122 	void		(*enable_ms)(struct uart_port *port);
123 	void		(*set_sicr)(struct uart_port *port, u32 val);
124 	void		(*set_imr)(struct uart_port *port, u16 val);
125 	u8		(*get_mr1)(struct uart_port *port);
126 };
127 
128 /* setting the prescaler and divisor reg is common for all chips */
129 static inline void mpc52xx_set_divisor(struct mpc52xx_psc __iomem *psc,
130 				       u16 prescaler, unsigned int divisor)
131 {
132 	/* select prescaler */
133 	out_be16(&psc->mpc52xx_psc_clock_select, prescaler);
134 	out_8(&psc->ctur, divisor >> 8);
135 	out_8(&psc->ctlr, divisor & 0xff);
136 }
137 
138 static u16 mpc52xx_psc_get_status(struct uart_port *port)
139 {
140 	return in_be16(&PSC(port)->mpc52xx_psc_status);
141 }
142 
143 static u8 mpc52xx_psc_get_ipcr(struct uart_port *port)
144 {
145 	return in_8(&PSC(port)->mpc52xx_psc_ipcr);
146 }
147 
148 static void mpc52xx_psc_command(struct uart_port *port, u8 cmd)
149 {
150 	out_8(&PSC(port)->command, cmd);
151 }
152 
153 static void mpc52xx_psc_set_mode(struct uart_port *port, u8 mr1, u8 mr2)
154 {
155 	out_8(&PSC(port)->command, MPC52xx_PSC_SEL_MODE_REG_1);
156 	out_8(&PSC(port)->mode, mr1);
157 	out_8(&PSC(port)->mode, mr2);
158 }
159 
160 static void mpc52xx_psc_set_rts(struct uart_port *port, int state)
161 {
162 	if (state)
163 		out_8(&PSC(port)->op1, MPC52xx_PSC_OP_RTS);
164 	else
165 		out_8(&PSC(port)->op0, MPC52xx_PSC_OP_RTS);
166 }
167 
168 static void mpc52xx_psc_enable_ms(struct uart_port *port)
169 {
170 	struct mpc52xx_psc __iomem *psc = PSC(port);
171 
172 	/* clear D_*-bits by reading them */
173 	in_8(&psc->mpc52xx_psc_ipcr);
174 	/* enable CTS and DCD as IPC interrupts */
175 	out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD);
176 
177 	port->read_status_mask |= MPC52xx_PSC_IMR_IPC;
178 	out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
179 }
180 
181 static void mpc52xx_psc_set_sicr(struct uart_port *port, u32 val)
182 {
183 	out_be32(&PSC(port)->sicr, val);
184 }
185 
186 static void mpc52xx_psc_set_imr(struct uart_port *port, u16 val)
187 {
188 	out_be16(&PSC(port)->mpc52xx_psc_imr, val);
189 }
190 
191 static u8 mpc52xx_psc_get_mr1(struct uart_port *port)
192 {
193 	out_8(&PSC(port)->command, MPC52xx_PSC_SEL_MODE_REG_1);
194 	return in_8(&PSC(port)->mode);
195 }
196 
197 #ifdef CONFIG_PPC_MPC52xx
198 #define FIFO_52xx(port) ((struct mpc52xx_psc_fifo __iomem *)(PSC(port)+1))
199 static void mpc52xx_psc_fifo_init(struct uart_port *port)
200 {
201 	struct mpc52xx_psc __iomem *psc = PSC(port);
202 	struct mpc52xx_psc_fifo __iomem *fifo = FIFO_52xx(port);
203 
204 	out_8(&fifo->rfcntl, 0x00);
205 	out_be16(&fifo->rfalarm, 0x1ff);
206 	out_8(&fifo->tfcntl, 0x07);
207 	out_be16(&fifo->tfalarm, 0x80);
208 
209 	port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY;
210 	out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
211 }
212 
213 static int mpc52xx_psc_raw_rx_rdy(struct uart_port *port)
214 {
215 	return in_be16(&PSC(port)->mpc52xx_psc_status)
216 	    & MPC52xx_PSC_SR_RXRDY;
217 }
218 
219 static int mpc52xx_psc_raw_tx_rdy(struct uart_port *port)
220 {
221 	return in_be16(&PSC(port)->mpc52xx_psc_status)
222 	    & MPC52xx_PSC_SR_TXRDY;
223 }
224 
225 
226 static int mpc52xx_psc_rx_rdy(struct uart_port *port)
227 {
228 	return in_be16(&PSC(port)->mpc52xx_psc_isr)
229 	    & port->read_status_mask
230 	    & MPC52xx_PSC_IMR_RXRDY;
231 }
232 
233 static int mpc52xx_psc_tx_rdy(struct uart_port *port)
234 {
235 	return in_be16(&PSC(port)->mpc52xx_psc_isr)
236 	    & port->read_status_mask
237 	    & MPC52xx_PSC_IMR_TXRDY;
238 }
239 
240 static int mpc52xx_psc_tx_empty(struct uart_port *port)
241 {
242 	u16 sts = in_be16(&PSC(port)->mpc52xx_psc_status);
243 
244 	return (sts & MPC52xx_PSC_SR_TXEMP) ? TIOCSER_TEMT : 0;
245 }
246 
247 static void mpc52xx_psc_start_tx(struct uart_port *port)
248 {
249 	port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
250 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
251 }
252 
253 static void mpc52xx_psc_stop_tx(struct uart_port *port)
254 {
255 	port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY;
256 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
257 }
258 
259 static void mpc52xx_psc_stop_rx(struct uart_port *port)
260 {
261 	port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY;
262 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
263 }
264 
265 static void mpc52xx_psc_rx_clr_irq(struct uart_port *port)
266 {
267 }
268 
269 static void mpc52xx_psc_tx_clr_irq(struct uart_port *port)
270 {
271 }
272 
273 static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char c)
274 {
275 	out_8(&PSC(port)->mpc52xx_psc_buffer_8, c);
276 }
277 
278 static unsigned char mpc52xx_psc_read_char(struct uart_port *port)
279 {
280 	return in_8(&PSC(port)->mpc52xx_psc_buffer_8);
281 }
282 
283 static void mpc52xx_psc_cw_disable_ints(struct uart_port *port)
284 {
285 	out_be16(&PSC(port)->mpc52xx_psc_imr, 0);
286 }
287 
288 static void mpc52xx_psc_cw_restore_ints(struct uart_port *port)
289 {
290 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
291 }
292 
293 static unsigned int mpc5200_psc_set_baudrate(struct uart_port *port,
294 					     struct ktermios *new,
295 					     struct ktermios *old)
296 {
297 	unsigned int baud;
298 	unsigned int divisor;
299 
300 	/* The 5200 has a fixed /32 prescaler, uartclk contains the ipb freq */
301 	baud = uart_get_baud_rate(port, new, old,
302 				  port->uartclk / (32 * 0xffff) + 1,
303 				  port->uartclk / 32);
304 	divisor = (port->uartclk + 16 * baud) / (32 * baud);
305 
306 	/* enable the /32 prescaler and set the divisor */
307 	mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
308 	return baud;
309 }
310 
311 static unsigned int mpc5200b_psc_set_baudrate(struct uart_port *port,
312 					      struct ktermios *new,
313 					      struct ktermios *old)
314 {
315 	unsigned int baud;
316 	unsigned int divisor;
317 	u16 prescaler;
318 
319 	/* The 5200B has a selectable /4 or /32 prescaler, uartclk contains the
320 	 * ipb freq */
321 	baud = uart_get_baud_rate(port, new, old,
322 				  port->uartclk / (32 * 0xffff) + 1,
323 				  port->uartclk / 4);
324 	divisor = (port->uartclk + 2 * baud) / (4 * baud);
325 
326 	/* select the proper prescaler and set the divisor
327 	 * prefer high prescaler for more tolerance on low baudrates */
328 	if (divisor > 0xffff || baud <= 115200) {
329 		divisor = (divisor + 4) / 8;
330 		prescaler = 0xdd00; /* /32 */
331 	} else
332 		prescaler = 0xff00; /* /4 */
333 	mpc52xx_set_divisor(PSC(port), prescaler, divisor);
334 	return baud;
335 }
336 
337 static void mpc52xx_psc_get_irq(struct uart_port *port, struct device_node *np)
338 {
339 	port->irqflags = 0;
340 	port->irq = irq_of_parse_and_map(np, 0);
341 }
342 
343 /* 52xx specific interrupt handler. The caller holds the port lock */
344 static irqreturn_t mpc52xx_psc_handle_irq(struct uart_port *port)
345 {
346 	return mpc5xxx_uart_process_int(port);
347 }
348 
349 static struct psc_ops mpc52xx_psc_ops = {
350 	.fifo_init = mpc52xx_psc_fifo_init,
351 	.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
352 	.raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
353 	.rx_rdy = mpc52xx_psc_rx_rdy,
354 	.tx_rdy = mpc52xx_psc_tx_rdy,
355 	.tx_empty = mpc52xx_psc_tx_empty,
356 	.stop_rx = mpc52xx_psc_stop_rx,
357 	.start_tx = mpc52xx_psc_start_tx,
358 	.stop_tx = mpc52xx_psc_stop_tx,
359 	.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
360 	.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
361 	.write_char = mpc52xx_psc_write_char,
362 	.read_char = mpc52xx_psc_read_char,
363 	.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
364 	.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
365 	.set_baudrate = mpc5200_psc_set_baudrate,
366 	.get_irq = mpc52xx_psc_get_irq,
367 	.handle_irq = mpc52xx_psc_handle_irq,
368 	.get_status = mpc52xx_psc_get_status,
369 	.get_ipcr = mpc52xx_psc_get_ipcr,
370 	.command = mpc52xx_psc_command,
371 	.set_mode = mpc52xx_psc_set_mode,
372 	.set_rts = mpc52xx_psc_set_rts,
373 	.enable_ms = mpc52xx_psc_enable_ms,
374 	.set_sicr = mpc52xx_psc_set_sicr,
375 	.set_imr = mpc52xx_psc_set_imr,
376 	.get_mr1 = mpc52xx_psc_get_mr1,
377 };
378 
379 static struct psc_ops mpc5200b_psc_ops = {
380 	.fifo_init = mpc52xx_psc_fifo_init,
381 	.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
382 	.raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
383 	.rx_rdy = mpc52xx_psc_rx_rdy,
384 	.tx_rdy = mpc52xx_psc_tx_rdy,
385 	.tx_empty = mpc52xx_psc_tx_empty,
386 	.stop_rx = mpc52xx_psc_stop_rx,
387 	.start_tx = mpc52xx_psc_start_tx,
388 	.stop_tx = mpc52xx_psc_stop_tx,
389 	.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
390 	.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
391 	.write_char = mpc52xx_psc_write_char,
392 	.read_char = mpc52xx_psc_read_char,
393 	.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
394 	.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
395 	.set_baudrate = mpc5200b_psc_set_baudrate,
396 	.get_irq = mpc52xx_psc_get_irq,
397 	.handle_irq = mpc52xx_psc_handle_irq,
398 	.get_status = mpc52xx_psc_get_status,
399 	.get_ipcr = mpc52xx_psc_get_ipcr,
400 	.command = mpc52xx_psc_command,
401 	.set_mode = mpc52xx_psc_set_mode,
402 	.set_rts = mpc52xx_psc_set_rts,
403 	.enable_ms = mpc52xx_psc_enable_ms,
404 	.set_sicr = mpc52xx_psc_set_sicr,
405 	.set_imr = mpc52xx_psc_set_imr,
406 	.get_mr1 = mpc52xx_psc_get_mr1,
407 };
408 
409 #endif /* CONFIG_PPC_MPC52xx */
410 
411 #ifdef CONFIG_PPC_MPC512x
412 #define FIFO_512x(port) ((struct mpc512x_psc_fifo __iomem *)(PSC(port)+1))
413 
414 /* PSC FIFO Controller for mpc512x */
415 struct psc_fifoc {
416 	u32 fifoc_cmd;
417 	u32 fifoc_int;
418 	u32 fifoc_dma;
419 	u32 fifoc_axe;
420 	u32 fifoc_debug;
421 };
422 
423 static struct psc_fifoc __iomem *psc_fifoc;
424 static unsigned int psc_fifoc_irq;
425 static struct clk *psc_fifoc_clk;
426 
427 static void mpc512x_psc_fifo_init(struct uart_port *port)
428 {
429 	/* /32 prescaler */
430 	out_be16(&PSC(port)->mpc52xx_psc_clock_select, 0xdd00);
431 
432 	out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
433 	out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
434 	out_be32(&FIFO_512x(port)->txalarm, 1);
435 	out_be32(&FIFO_512x(port)->tximr, 0);
436 
437 	out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
438 	out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
439 	out_be32(&FIFO_512x(port)->rxalarm, 1);
440 	out_be32(&FIFO_512x(port)->rximr, 0);
441 
442 	out_be32(&FIFO_512x(port)->tximr, MPC512x_PSC_FIFO_ALARM);
443 	out_be32(&FIFO_512x(port)->rximr, MPC512x_PSC_FIFO_ALARM);
444 }
445 
446 static int mpc512x_psc_raw_rx_rdy(struct uart_port *port)
447 {
448 	return !(in_be32(&FIFO_512x(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
449 }
450 
451 static int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
452 {
453 	return !(in_be32(&FIFO_512x(port)->txsr) & MPC512x_PSC_FIFO_FULL);
454 }
455 
456 static int mpc512x_psc_rx_rdy(struct uart_port *port)
457 {
458 	return in_be32(&FIFO_512x(port)->rxsr)
459 	    & in_be32(&FIFO_512x(port)->rximr)
460 	    & MPC512x_PSC_FIFO_ALARM;
461 }
462 
463 static int mpc512x_psc_tx_rdy(struct uart_port *port)
464 {
465 	return in_be32(&FIFO_512x(port)->txsr)
466 	    & in_be32(&FIFO_512x(port)->tximr)
467 	    & MPC512x_PSC_FIFO_ALARM;
468 }
469 
470 static int mpc512x_psc_tx_empty(struct uart_port *port)
471 {
472 	return in_be32(&FIFO_512x(port)->txsr)
473 	    & MPC512x_PSC_FIFO_EMPTY;
474 }
475 
476 static void mpc512x_psc_stop_rx(struct uart_port *port)
477 {
478 	unsigned long rx_fifo_imr;
479 
480 	rx_fifo_imr = in_be32(&FIFO_512x(port)->rximr);
481 	rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
482 	out_be32(&FIFO_512x(port)->rximr, rx_fifo_imr);
483 }
484 
485 static void mpc512x_psc_start_tx(struct uart_port *port)
486 {
487 	unsigned long tx_fifo_imr;
488 
489 	tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
490 	tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
491 	out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
492 }
493 
494 static void mpc512x_psc_stop_tx(struct uart_port *port)
495 {
496 	unsigned long tx_fifo_imr;
497 
498 	tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
499 	tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
500 	out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
501 }
502 
503 static void mpc512x_psc_rx_clr_irq(struct uart_port *port)
504 {
505 	out_be32(&FIFO_512x(port)->rxisr, in_be32(&FIFO_512x(port)->rxisr));
506 }
507 
508 static void mpc512x_psc_tx_clr_irq(struct uart_port *port)
509 {
510 	out_be32(&FIFO_512x(port)->txisr, in_be32(&FIFO_512x(port)->txisr));
511 }
512 
513 static void mpc512x_psc_write_char(struct uart_port *port, unsigned char c)
514 {
515 	out_8(&FIFO_512x(port)->txdata_8, c);
516 }
517 
518 static unsigned char mpc512x_psc_read_char(struct uart_port *port)
519 {
520 	return in_8(&FIFO_512x(port)->rxdata_8);
521 }
522 
523 static void mpc512x_psc_cw_disable_ints(struct uart_port *port)
524 {
525 	port->read_status_mask =
526 		in_be32(&FIFO_512x(port)->tximr) << 16 |
527 		in_be32(&FIFO_512x(port)->rximr);
528 	out_be32(&FIFO_512x(port)->tximr, 0);
529 	out_be32(&FIFO_512x(port)->rximr, 0);
530 }
531 
532 static void mpc512x_psc_cw_restore_ints(struct uart_port *port)
533 {
534 	out_be32(&FIFO_512x(port)->tximr,
535 		(port->read_status_mask >> 16) & 0x7f);
536 	out_be32(&FIFO_512x(port)->rximr, port->read_status_mask & 0x7f);
537 }
538 
539 static unsigned int mpc512x_psc_set_baudrate(struct uart_port *port,
540 					     struct ktermios *new,
541 					     struct ktermios *old)
542 {
543 	unsigned int baud;
544 	unsigned int divisor;
545 
546 	/*
547 	 * The "MPC5121e Microcontroller Reference Manual, Rev. 3" says on
548 	 * pg. 30-10 that the chip supports a /32 and a /10 prescaler.
549 	 * Furthermore, it states that "After reset, the prescaler by 10
550 	 * for the UART mode is selected", but the reset register value is
551 	 * 0x0000 which means a /32 prescaler. This is wrong.
552 	 *
553 	 * In reality using /32 prescaler doesn't work, as it is not supported!
554 	 * Use /16 or /10 prescaler, see "MPC5121e Hardware Design Guide",
555 	 * Chapter 4.1 PSC in UART Mode.
556 	 * Calculate with a /16 prescaler here.
557 	 */
558 
559 	/* uartclk contains the ips freq */
560 	baud = uart_get_baud_rate(port, new, old,
561 				  port->uartclk / (16 * 0xffff) + 1,
562 				  port->uartclk / 16);
563 	divisor = (port->uartclk + 8 * baud) / (16 * baud);
564 
565 	/* enable the /16 prescaler and set the divisor */
566 	mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
567 	return baud;
568 }
569 
570 /* Init PSC FIFO Controller */
571 static int __init mpc512x_psc_fifoc_init(void)
572 {
573 	int err;
574 	struct device_node *np;
575 	struct clk *clk;
576 
577 	/* default error code, potentially overwritten by clock calls */
578 	err = -ENODEV;
579 
580 	np = of_find_compatible_node(NULL, NULL,
581 				     "fsl,mpc5121-psc-fifo");
582 	if (!np) {
583 		pr_err("%s: Can't find FIFOC node\n", __func__);
584 		goto out_err;
585 	}
586 
587 	clk = of_clk_get(np, 0);
588 	if (IS_ERR(clk)) {
589 		/* backwards compat with device trees that lack clock specs */
590 		clk = clk_get_sys(np->name, "ipg");
591 	}
592 	if (IS_ERR(clk)) {
593 		pr_err("%s: Can't lookup FIFO clock\n", __func__);
594 		err = PTR_ERR(clk);
595 		goto out_ofnode_put;
596 	}
597 	if (clk_prepare_enable(clk)) {
598 		pr_err("%s: Can't enable FIFO clock\n", __func__);
599 		clk_put(clk);
600 		goto out_ofnode_put;
601 	}
602 	psc_fifoc_clk = clk;
603 
604 	psc_fifoc = of_iomap(np, 0);
605 	if (!psc_fifoc) {
606 		pr_err("%s: Can't map FIFOC\n", __func__);
607 		goto out_clk_disable;
608 	}
609 
610 	psc_fifoc_irq = irq_of_parse_and_map(np, 0);
611 	if (psc_fifoc_irq == 0) {
612 		pr_err("%s: Can't get FIFOC irq\n", __func__);
613 		goto out_unmap;
614 	}
615 
616 	of_node_put(np);
617 	return 0;
618 
619 out_unmap:
620 	iounmap(psc_fifoc);
621 out_clk_disable:
622 	clk_disable_unprepare(psc_fifoc_clk);
623 	clk_put(psc_fifoc_clk);
624 out_ofnode_put:
625 	of_node_put(np);
626 out_err:
627 	return err;
628 }
629 
630 static void __exit mpc512x_psc_fifoc_uninit(void)
631 {
632 	iounmap(psc_fifoc);
633 
634 	/* disable the clock, errors are not fatal */
635 	if (psc_fifoc_clk) {
636 		clk_disable_unprepare(psc_fifoc_clk);
637 		clk_put(psc_fifoc_clk);
638 		psc_fifoc_clk = NULL;
639 	}
640 }
641 
642 /* 512x specific interrupt handler. The caller holds the port lock */
643 static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port)
644 {
645 	unsigned long fifoc_int;
646 	int psc_num;
647 
648 	/* Read pending PSC FIFOC interrupts */
649 	fifoc_int = in_be32(&psc_fifoc->fifoc_int);
650 
651 	/* Check if it is an interrupt for this port */
652 	psc_num = (port->mapbase & 0xf00) >> 8;
653 	if (test_bit(psc_num, &fifoc_int) ||
654 	    test_bit(psc_num + 16, &fifoc_int))
655 		return mpc5xxx_uart_process_int(port);
656 
657 	return IRQ_NONE;
658 }
659 
660 static struct clk *psc_mclk_clk[MPC52xx_PSC_MAXNUM];
661 static struct clk *psc_ipg_clk[MPC52xx_PSC_MAXNUM];
662 
663 /* called from within the .request_port() callback (allocation) */
664 static int mpc512x_psc_alloc_clock(struct uart_port *port)
665 {
666 	int psc_num;
667 	struct clk *clk;
668 	int err;
669 
670 	psc_num = (port->mapbase & 0xf00) >> 8;
671 
672 	clk = devm_clk_get(port->dev, "mclk");
673 	if (IS_ERR(clk)) {
674 		dev_err(port->dev, "Failed to get MCLK!\n");
675 		err = PTR_ERR(clk);
676 		goto out_err;
677 	}
678 	err = clk_prepare_enable(clk);
679 	if (err) {
680 		dev_err(port->dev, "Failed to enable MCLK!\n");
681 		goto out_err;
682 	}
683 	psc_mclk_clk[psc_num] = clk;
684 
685 	clk = devm_clk_get(port->dev, "ipg");
686 	if (IS_ERR(clk)) {
687 		dev_err(port->dev, "Failed to get IPG clock!\n");
688 		err = PTR_ERR(clk);
689 		goto out_err;
690 	}
691 	err = clk_prepare_enable(clk);
692 	if (err) {
693 		dev_err(port->dev, "Failed to enable IPG clock!\n");
694 		goto out_err;
695 	}
696 	psc_ipg_clk[psc_num] = clk;
697 
698 	return 0;
699 
700 out_err:
701 	if (psc_mclk_clk[psc_num]) {
702 		clk_disable_unprepare(psc_mclk_clk[psc_num]);
703 		psc_mclk_clk[psc_num] = NULL;
704 	}
705 	if (psc_ipg_clk[psc_num]) {
706 		clk_disable_unprepare(psc_ipg_clk[psc_num]);
707 		psc_ipg_clk[psc_num] = NULL;
708 	}
709 	return err;
710 }
711 
712 /* called from within the .release_port() callback (release) */
713 static void mpc512x_psc_relse_clock(struct uart_port *port)
714 {
715 	int psc_num;
716 	struct clk *clk;
717 
718 	psc_num = (port->mapbase & 0xf00) >> 8;
719 	clk = psc_mclk_clk[psc_num];
720 	if (clk) {
721 		clk_disable_unprepare(clk);
722 		psc_mclk_clk[psc_num] = NULL;
723 	}
724 	if (psc_ipg_clk[psc_num]) {
725 		clk_disable_unprepare(psc_ipg_clk[psc_num]);
726 		psc_ipg_clk[psc_num] = NULL;
727 	}
728 }
729 
730 /* implementation of the .clock() callback (enable/disable) */
731 static int mpc512x_psc_endis_clock(struct uart_port *port, int enable)
732 {
733 	int psc_num;
734 	struct clk *psc_clk;
735 	int ret;
736 
737 	if (uart_console(port))
738 		return 0;
739 
740 	psc_num = (port->mapbase & 0xf00) >> 8;
741 	psc_clk = psc_mclk_clk[psc_num];
742 	if (!psc_clk) {
743 		dev_err(port->dev, "Failed to get PSC clock entry!\n");
744 		return -ENODEV;
745 	}
746 
747 	dev_dbg(port->dev, "mclk %sable\n", enable ? "en" : "dis");
748 	if (enable) {
749 		ret = clk_enable(psc_clk);
750 		if (ret)
751 			dev_err(port->dev, "Failed to enable MCLK!\n");
752 		return ret;
753 	} else {
754 		clk_disable(psc_clk);
755 		return 0;
756 	}
757 }
758 
759 static void mpc512x_psc_get_irq(struct uart_port *port, struct device_node *np)
760 {
761 	port->irqflags = IRQF_SHARED;
762 	port->irq = psc_fifoc_irq;
763 }
764 #endif
765 
766 #ifdef CONFIG_PPC_MPC512x
767 
768 #define PSC_5125(port) ((struct mpc5125_psc __iomem *)((port)->membase))
769 #define FIFO_5125(port) ((struct mpc512x_psc_fifo __iomem *)(PSC_5125(port)+1))
770 
771 static void mpc5125_psc_fifo_init(struct uart_port *port)
772 {
773 	/* /32 prescaler */
774 	out_8(&PSC_5125(port)->mpc52xx_psc_clock_select, 0xdd);
775 
776 	out_be32(&FIFO_5125(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
777 	out_be32(&FIFO_5125(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
778 	out_be32(&FIFO_5125(port)->txalarm, 1);
779 	out_be32(&FIFO_5125(port)->tximr, 0);
780 
781 	out_be32(&FIFO_5125(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
782 	out_be32(&FIFO_5125(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
783 	out_be32(&FIFO_5125(port)->rxalarm, 1);
784 	out_be32(&FIFO_5125(port)->rximr, 0);
785 
786 	out_be32(&FIFO_5125(port)->tximr, MPC512x_PSC_FIFO_ALARM);
787 	out_be32(&FIFO_5125(port)->rximr, MPC512x_PSC_FIFO_ALARM);
788 }
789 
790 static int mpc5125_psc_raw_rx_rdy(struct uart_port *port)
791 {
792 	return !(in_be32(&FIFO_5125(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
793 }
794 
795 static int mpc5125_psc_raw_tx_rdy(struct uart_port *port)
796 {
797 	return !(in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_FULL);
798 }
799 
800 static int mpc5125_psc_rx_rdy(struct uart_port *port)
801 {
802 	return in_be32(&FIFO_5125(port)->rxsr) &
803 	       in_be32(&FIFO_5125(port)->rximr) & MPC512x_PSC_FIFO_ALARM;
804 }
805 
806 static int mpc5125_psc_tx_rdy(struct uart_port *port)
807 {
808 	return in_be32(&FIFO_5125(port)->txsr) &
809 	       in_be32(&FIFO_5125(port)->tximr) & MPC512x_PSC_FIFO_ALARM;
810 }
811 
812 static int mpc5125_psc_tx_empty(struct uart_port *port)
813 {
814 	return in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_EMPTY;
815 }
816 
817 static void mpc5125_psc_stop_rx(struct uart_port *port)
818 {
819 	unsigned long rx_fifo_imr;
820 
821 	rx_fifo_imr = in_be32(&FIFO_5125(port)->rximr);
822 	rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
823 	out_be32(&FIFO_5125(port)->rximr, rx_fifo_imr);
824 }
825 
826 static void mpc5125_psc_start_tx(struct uart_port *port)
827 {
828 	unsigned long tx_fifo_imr;
829 
830 	tx_fifo_imr = in_be32(&FIFO_5125(port)->tximr);
831 	tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
832 	out_be32(&FIFO_5125(port)->tximr, tx_fifo_imr);
833 }
834 
835 static void mpc5125_psc_stop_tx(struct uart_port *port)
836 {
837 	unsigned long tx_fifo_imr;
838 
839 	tx_fifo_imr = in_be32(&FIFO_5125(port)->tximr);
840 	tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
841 	out_be32(&FIFO_5125(port)->tximr, tx_fifo_imr);
842 }
843 
844 static void mpc5125_psc_rx_clr_irq(struct uart_port *port)
845 {
846 	out_be32(&FIFO_5125(port)->rxisr, in_be32(&FIFO_5125(port)->rxisr));
847 }
848 
849 static void mpc5125_psc_tx_clr_irq(struct uart_port *port)
850 {
851 	out_be32(&FIFO_5125(port)->txisr, in_be32(&FIFO_5125(port)->txisr));
852 }
853 
854 static void mpc5125_psc_write_char(struct uart_port *port, unsigned char c)
855 {
856 	out_8(&FIFO_5125(port)->txdata_8, c);
857 }
858 
859 static unsigned char mpc5125_psc_read_char(struct uart_port *port)
860 {
861 	return in_8(&FIFO_5125(port)->rxdata_8);
862 }
863 
864 static void mpc5125_psc_cw_disable_ints(struct uart_port *port)
865 {
866 	port->read_status_mask =
867 		in_be32(&FIFO_5125(port)->tximr) << 16 |
868 		in_be32(&FIFO_5125(port)->rximr);
869 	out_be32(&FIFO_5125(port)->tximr, 0);
870 	out_be32(&FIFO_5125(port)->rximr, 0);
871 }
872 
873 static void mpc5125_psc_cw_restore_ints(struct uart_port *port)
874 {
875 	out_be32(&FIFO_5125(port)->tximr,
876 		(port->read_status_mask >> 16) & 0x7f);
877 	out_be32(&FIFO_5125(port)->rximr, port->read_status_mask & 0x7f);
878 }
879 
880 static inline void mpc5125_set_divisor(struct mpc5125_psc __iomem *psc,
881 		u8 prescaler, unsigned int divisor)
882 {
883 	/* select prescaler */
884 	out_8(&psc->mpc52xx_psc_clock_select, prescaler);
885 	out_8(&psc->ctur, divisor >> 8);
886 	out_8(&psc->ctlr, divisor & 0xff);
887 }
888 
889 static unsigned int mpc5125_psc_set_baudrate(struct uart_port *port,
890 					     struct ktermios *new,
891 					     struct ktermios *old)
892 {
893 	unsigned int baud;
894 	unsigned int divisor;
895 
896 	/*
897 	 * Calculate with a /16 prescaler here.
898 	 */
899 
900 	/* uartclk contains the ips freq */
901 	baud = uart_get_baud_rate(port, new, old,
902 				  port->uartclk / (16 * 0xffff) + 1,
903 				  port->uartclk / 16);
904 	divisor = (port->uartclk + 8 * baud) / (16 * baud);
905 
906 	/* enable the /16 prescaler and set the divisor */
907 	mpc5125_set_divisor(PSC_5125(port), 0xdd, divisor);
908 	return baud;
909 }
910 
911 /*
912  * MPC5125 have compatible PSC FIFO Controller.
913  * Special init not needed.
914  */
915 static u16 mpc5125_psc_get_status(struct uart_port *port)
916 {
917 	return in_be16(&PSC_5125(port)->mpc52xx_psc_status);
918 }
919 
920 static u8 mpc5125_psc_get_ipcr(struct uart_port *port)
921 {
922 	return in_8(&PSC_5125(port)->mpc52xx_psc_ipcr);
923 }
924 
925 static void mpc5125_psc_command(struct uart_port *port, u8 cmd)
926 {
927 	out_8(&PSC_5125(port)->command, cmd);
928 }
929 
930 static void mpc5125_psc_set_mode(struct uart_port *port, u8 mr1, u8 mr2)
931 {
932 	out_8(&PSC_5125(port)->mr1, mr1);
933 	out_8(&PSC_5125(port)->mr2, mr2);
934 }
935 
936 static void mpc5125_psc_set_rts(struct uart_port *port, int state)
937 {
938 	if (state & TIOCM_RTS)
939 		out_8(&PSC_5125(port)->op1, MPC52xx_PSC_OP_RTS);
940 	else
941 		out_8(&PSC_5125(port)->op0, MPC52xx_PSC_OP_RTS);
942 }
943 
944 static void mpc5125_psc_enable_ms(struct uart_port *port)
945 {
946 	struct mpc5125_psc __iomem *psc = PSC_5125(port);
947 
948 	/* clear D_*-bits by reading them */
949 	in_8(&psc->mpc52xx_psc_ipcr);
950 	/* enable CTS and DCD as IPC interrupts */
951 	out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD);
952 
953 	port->read_status_mask |= MPC52xx_PSC_IMR_IPC;
954 	out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
955 }
956 
957 static void mpc5125_psc_set_sicr(struct uart_port *port, u32 val)
958 {
959 	out_be32(&PSC_5125(port)->sicr, val);
960 }
961 
962 static void mpc5125_psc_set_imr(struct uart_port *port, u16 val)
963 {
964 	out_be16(&PSC_5125(port)->mpc52xx_psc_imr, val);
965 }
966 
967 static u8 mpc5125_psc_get_mr1(struct uart_port *port)
968 {
969 	return in_8(&PSC_5125(port)->mr1);
970 }
971 
972 static struct psc_ops mpc5125_psc_ops = {
973 	.fifo_init = mpc5125_psc_fifo_init,
974 	.raw_rx_rdy = mpc5125_psc_raw_rx_rdy,
975 	.raw_tx_rdy = mpc5125_psc_raw_tx_rdy,
976 	.rx_rdy = mpc5125_psc_rx_rdy,
977 	.tx_rdy = mpc5125_psc_tx_rdy,
978 	.tx_empty = mpc5125_psc_tx_empty,
979 	.stop_rx = mpc5125_psc_stop_rx,
980 	.start_tx = mpc5125_psc_start_tx,
981 	.stop_tx = mpc5125_psc_stop_tx,
982 	.rx_clr_irq = mpc5125_psc_rx_clr_irq,
983 	.tx_clr_irq = mpc5125_psc_tx_clr_irq,
984 	.write_char = mpc5125_psc_write_char,
985 	.read_char = mpc5125_psc_read_char,
986 	.cw_disable_ints = mpc5125_psc_cw_disable_ints,
987 	.cw_restore_ints = mpc5125_psc_cw_restore_ints,
988 	.set_baudrate = mpc5125_psc_set_baudrate,
989 	.clock_alloc = mpc512x_psc_alloc_clock,
990 	.clock_relse = mpc512x_psc_relse_clock,
991 	.clock = mpc512x_psc_endis_clock,
992 	.fifoc_init = mpc512x_psc_fifoc_init,
993 	.fifoc_uninit = mpc512x_psc_fifoc_uninit,
994 	.get_irq = mpc512x_psc_get_irq,
995 	.handle_irq = mpc512x_psc_handle_irq,
996 	.get_status = mpc5125_psc_get_status,
997 	.get_ipcr = mpc5125_psc_get_ipcr,
998 	.command = mpc5125_psc_command,
999 	.set_mode = mpc5125_psc_set_mode,
1000 	.set_rts = mpc5125_psc_set_rts,
1001 	.enable_ms = mpc5125_psc_enable_ms,
1002 	.set_sicr = mpc5125_psc_set_sicr,
1003 	.set_imr = mpc5125_psc_set_imr,
1004 	.get_mr1 = mpc5125_psc_get_mr1,
1005 };
1006 
1007 static struct psc_ops mpc512x_psc_ops = {
1008 	.fifo_init = mpc512x_psc_fifo_init,
1009 	.raw_rx_rdy = mpc512x_psc_raw_rx_rdy,
1010 	.raw_tx_rdy = mpc512x_psc_raw_tx_rdy,
1011 	.rx_rdy = mpc512x_psc_rx_rdy,
1012 	.tx_rdy = mpc512x_psc_tx_rdy,
1013 	.tx_empty = mpc512x_psc_tx_empty,
1014 	.stop_rx = mpc512x_psc_stop_rx,
1015 	.start_tx = mpc512x_psc_start_tx,
1016 	.stop_tx = mpc512x_psc_stop_tx,
1017 	.rx_clr_irq = mpc512x_psc_rx_clr_irq,
1018 	.tx_clr_irq = mpc512x_psc_tx_clr_irq,
1019 	.write_char = mpc512x_psc_write_char,
1020 	.read_char = mpc512x_psc_read_char,
1021 	.cw_disable_ints = mpc512x_psc_cw_disable_ints,
1022 	.cw_restore_ints = mpc512x_psc_cw_restore_ints,
1023 	.set_baudrate = mpc512x_psc_set_baudrate,
1024 	.clock_alloc = mpc512x_psc_alloc_clock,
1025 	.clock_relse = mpc512x_psc_relse_clock,
1026 	.clock = mpc512x_psc_endis_clock,
1027 	.fifoc_init = mpc512x_psc_fifoc_init,
1028 	.fifoc_uninit = mpc512x_psc_fifoc_uninit,
1029 	.get_irq = mpc512x_psc_get_irq,
1030 	.handle_irq = mpc512x_psc_handle_irq,
1031 	.get_status = mpc52xx_psc_get_status,
1032 	.get_ipcr = mpc52xx_psc_get_ipcr,
1033 	.command = mpc52xx_psc_command,
1034 	.set_mode = mpc52xx_psc_set_mode,
1035 	.set_rts = mpc52xx_psc_set_rts,
1036 	.enable_ms = mpc52xx_psc_enable_ms,
1037 	.set_sicr = mpc52xx_psc_set_sicr,
1038 	.set_imr = mpc52xx_psc_set_imr,
1039 	.get_mr1 = mpc52xx_psc_get_mr1,
1040 };
1041 #endif /* CONFIG_PPC_MPC512x */
1042 
1043 
1044 static const struct psc_ops *psc_ops;
1045 
1046 /* ======================================================================== */
1047 /* UART operations                                                          */
1048 /* ======================================================================== */
1049 
1050 static unsigned int
1051 mpc52xx_uart_tx_empty(struct uart_port *port)
1052 {
1053 	return psc_ops->tx_empty(port) ? TIOCSER_TEMT : 0;
1054 }
1055 
1056 static void
1057 mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1058 {
1059 	psc_ops->set_rts(port, mctrl & TIOCM_RTS);
1060 }
1061 
1062 static unsigned int
1063 mpc52xx_uart_get_mctrl(struct uart_port *port)
1064 {
1065 	unsigned int ret = TIOCM_DSR;
1066 	u8 status = psc_ops->get_ipcr(port);
1067 
1068 	if (!(status & MPC52xx_PSC_CTS))
1069 		ret |= TIOCM_CTS;
1070 	if (!(status & MPC52xx_PSC_DCD))
1071 		ret |= TIOCM_CAR;
1072 
1073 	return ret;
1074 }
1075 
1076 static void
1077 mpc52xx_uart_stop_tx(struct uart_port *port)
1078 {
1079 	/* port->lock taken by caller */
1080 	psc_ops->stop_tx(port);
1081 }
1082 
1083 static void
1084 mpc52xx_uart_start_tx(struct uart_port *port)
1085 {
1086 	/* port->lock taken by caller */
1087 	psc_ops->start_tx(port);
1088 }
1089 
1090 static void
1091 mpc52xx_uart_stop_rx(struct uart_port *port)
1092 {
1093 	/* port->lock taken by caller */
1094 	psc_ops->stop_rx(port);
1095 }
1096 
1097 static void
1098 mpc52xx_uart_enable_ms(struct uart_port *port)
1099 {
1100 	psc_ops->enable_ms(port);
1101 }
1102 
1103 static void
1104 mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
1105 {
1106 	unsigned long flags;
1107 	spin_lock_irqsave(&port->lock, flags);
1108 
1109 	if (ctl == -1)
1110 		psc_ops->command(port, MPC52xx_PSC_START_BRK);
1111 	else
1112 		psc_ops->command(port, MPC52xx_PSC_STOP_BRK);
1113 
1114 	spin_unlock_irqrestore(&port->lock, flags);
1115 }
1116 
1117 static int
1118 mpc52xx_uart_startup(struct uart_port *port)
1119 {
1120 	int ret;
1121 
1122 	if (psc_ops->clock) {
1123 		ret = psc_ops->clock(port, 1);
1124 		if (ret)
1125 			return ret;
1126 	}
1127 
1128 	/* Request IRQ */
1129 	ret = request_irq(port->irq, mpc52xx_uart_int,
1130 			  port->irqflags, "mpc52xx_psc_uart", port);
1131 	if (ret)
1132 		return ret;
1133 
1134 	/* Reset/activate the port, clear and enable interrupts */
1135 	psc_ops->command(port, MPC52xx_PSC_RST_RX);
1136 	psc_ops->command(port, MPC52xx_PSC_RST_TX);
1137 
1138 	/*
1139 	 * According to Freescale's support the RST_TX command can produce a
1140 	 * spike on the TX pin. So they recommend to delay "for one character".
1141 	 * One millisecond should be enough for everyone.
1142 	 */
1143 	msleep(1);
1144 
1145 	psc_ops->set_sicr(port, 0);	/* UART mode DCD ignored */
1146 
1147 	psc_ops->fifo_init(port);
1148 
1149 	psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
1150 	psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
1151 
1152 	return 0;
1153 }
1154 
1155 static void
1156 mpc52xx_uart_shutdown(struct uart_port *port)
1157 {
1158 	/* Shut down the port.  Leave TX active if on a console port */
1159 	psc_ops->command(port, MPC52xx_PSC_RST_RX);
1160 	if (!uart_console(port))
1161 		psc_ops->command(port, MPC52xx_PSC_RST_TX);
1162 
1163 	port->read_status_mask = 0;
1164 	psc_ops->set_imr(port, port->read_status_mask);
1165 
1166 	if (psc_ops->clock)
1167 		psc_ops->clock(port, 0);
1168 
1169 	/* Disable interrupt */
1170 	psc_ops->cw_disable_ints(port);
1171 
1172 	/* Release interrupt */
1173 	free_irq(port->irq, port);
1174 }
1175 
1176 static void
1177 mpc52xx_uart_set_termios(struct uart_port *port, struct ktermios *new,
1178 			 struct ktermios *old)
1179 {
1180 	unsigned long flags;
1181 	unsigned char mr1, mr2;
1182 	unsigned int j;
1183 	unsigned int baud;
1184 
1185 	/* Prepare what we're gonna write */
1186 	mr1 = 0;
1187 
1188 	switch (new->c_cflag & CSIZE) {
1189 	case CS5:	mr1 |= MPC52xx_PSC_MODE_5_BITS;
1190 		break;
1191 	case CS6:	mr1 |= MPC52xx_PSC_MODE_6_BITS;
1192 		break;
1193 	case CS7:	mr1 |= MPC52xx_PSC_MODE_7_BITS;
1194 		break;
1195 	case CS8:
1196 	default:	mr1 |= MPC52xx_PSC_MODE_8_BITS;
1197 	}
1198 
1199 	if (new->c_cflag & PARENB) {
1200 		if (new->c_cflag & CMSPAR)
1201 			mr1 |= MPC52xx_PSC_MODE_PARFORCE;
1202 
1203 		/* With CMSPAR, PARODD also means high parity (same as termios) */
1204 		mr1 |= (new->c_cflag & PARODD) ?
1205 			MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
1206 	} else {
1207 		mr1 |= MPC52xx_PSC_MODE_PARNONE;
1208 	}
1209 
1210 	mr2 = 0;
1211 
1212 	if (new->c_cflag & CSTOPB)
1213 		mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
1214 	else
1215 		mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
1216 			MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
1217 			MPC52xx_PSC_MODE_ONE_STOP;
1218 
1219 	if (new->c_cflag & CRTSCTS) {
1220 		mr1 |= MPC52xx_PSC_MODE_RXRTS;
1221 		mr2 |= MPC52xx_PSC_MODE_TXCTS;
1222 	}
1223 
1224 	/* Get the lock */
1225 	spin_lock_irqsave(&port->lock, flags);
1226 
1227 	/* Do our best to flush TX & RX, so we don't lose anything */
1228 	/* But we don't wait indefinitely ! */
1229 	j = 5000000;	/* Maximum wait */
1230 	/* FIXME Can't receive chars since set_termios might be called at early
1231 	 * boot for the console, all stuff is not yet ready to receive at that
1232 	 * time and that just makes the kernel oops */
1233 	/* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
1234 	while (!mpc52xx_uart_tx_empty(port) && --j)
1235 		udelay(1);
1236 
1237 	if (!j)
1238 		printk(KERN_ERR "mpc52xx_uart.c: "
1239 			"Unable to flush RX & TX fifos in-time in set_termios."
1240 			"Some chars may have been lost.\n");
1241 
1242 	/* Reset the TX & RX */
1243 	psc_ops->command(port, MPC52xx_PSC_RST_RX);
1244 	psc_ops->command(port, MPC52xx_PSC_RST_TX);
1245 
1246 	/* Send new mode settings */
1247 	psc_ops->set_mode(port, mr1, mr2);
1248 	baud = psc_ops->set_baudrate(port, new, old);
1249 
1250 	/* Update the per-port timeout */
1251 	uart_update_timeout(port, new->c_cflag, baud);
1252 
1253 	if (UART_ENABLE_MS(port, new->c_cflag))
1254 		mpc52xx_uart_enable_ms(port);
1255 
1256 	/* Reenable TX & RX */
1257 	psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
1258 	psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
1259 
1260 	/* We're all set, release the lock */
1261 	spin_unlock_irqrestore(&port->lock, flags);
1262 }
1263 
1264 static const char *
1265 mpc52xx_uart_type(struct uart_port *port)
1266 {
1267 	/*
1268 	 * We keep using PORT_MPC52xx for historic reasons although it applies
1269 	 * for MPC512x, too, but print "MPC5xxx" to not irritate users
1270 	 */
1271 	return port->type == PORT_MPC52xx ? "MPC5xxx PSC" : NULL;
1272 }
1273 
1274 static void
1275 mpc52xx_uart_release_port(struct uart_port *port)
1276 {
1277 	if (psc_ops->clock_relse)
1278 		psc_ops->clock_relse(port);
1279 
1280 	/* remapped by us ? */
1281 	if (port->flags & UPF_IOREMAP) {
1282 		iounmap(port->membase);
1283 		port->membase = NULL;
1284 	}
1285 
1286 	release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
1287 }
1288 
1289 static int
1290 mpc52xx_uart_request_port(struct uart_port *port)
1291 {
1292 	int err;
1293 
1294 	if (port->flags & UPF_IOREMAP) /* Need to remap ? */
1295 		port->membase = ioremap(port->mapbase,
1296 					sizeof(struct mpc52xx_psc));
1297 
1298 	if (!port->membase)
1299 		return -EINVAL;
1300 
1301 	err = request_mem_region(port->mapbase, sizeof(struct mpc52xx_psc),
1302 			"mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
1303 
1304 	if (err)
1305 		goto out_membase;
1306 
1307 	if (psc_ops->clock_alloc) {
1308 		err = psc_ops->clock_alloc(port);
1309 		if (err)
1310 			goto out_mapregion;
1311 	}
1312 
1313 	return 0;
1314 
1315 out_mapregion:
1316 	release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
1317 out_membase:
1318 	if (port->flags & UPF_IOREMAP) {
1319 		iounmap(port->membase);
1320 		port->membase = NULL;
1321 	}
1322 	return err;
1323 }
1324 
1325 static void
1326 mpc52xx_uart_config_port(struct uart_port *port, int flags)
1327 {
1328 	if ((flags & UART_CONFIG_TYPE)
1329 		&& (mpc52xx_uart_request_port(port) == 0))
1330 		port->type = PORT_MPC52xx;
1331 }
1332 
1333 static int
1334 mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
1335 {
1336 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx)
1337 		return -EINVAL;
1338 
1339 	if ((ser->irq != port->irq) ||
1340 	    (ser->io_type != UPIO_MEM) ||
1341 	    (ser->baud_base != port->uartclk)  ||
1342 	    (ser->iomem_base != (void *)port->mapbase) ||
1343 	    (ser->hub6 != 0))
1344 		return -EINVAL;
1345 
1346 	return 0;
1347 }
1348 
1349 
1350 static struct uart_ops mpc52xx_uart_ops = {
1351 	.tx_empty	= mpc52xx_uart_tx_empty,
1352 	.set_mctrl	= mpc52xx_uart_set_mctrl,
1353 	.get_mctrl	= mpc52xx_uart_get_mctrl,
1354 	.stop_tx	= mpc52xx_uart_stop_tx,
1355 	.start_tx	= mpc52xx_uart_start_tx,
1356 	.stop_rx	= mpc52xx_uart_stop_rx,
1357 	.enable_ms	= mpc52xx_uart_enable_ms,
1358 	.break_ctl	= mpc52xx_uart_break_ctl,
1359 	.startup	= mpc52xx_uart_startup,
1360 	.shutdown	= mpc52xx_uart_shutdown,
1361 	.set_termios	= mpc52xx_uart_set_termios,
1362 /*	.pm		= mpc52xx_uart_pm,		Not supported yet */
1363 	.type		= mpc52xx_uart_type,
1364 	.release_port	= mpc52xx_uart_release_port,
1365 	.request_port	= mpc52xx_uart_request_port,
1366 	.config_port	= mpc52xx_uart_config_port,
1367 	.verify_port	= mpc52xx_uart_verify_port
1368 };
1369 
1370 
1371 /* ======================================================================== */
1372 /* Interrupt handling                                                       */
1373 /* ======================================================================== */
1374 
1375 static inline int
1376 mpc52xx_uart_int_rx_chars(struct uart_port *port)
1377 {
1378 	struct tty_port *tport = &port->state->port;
1379 	unsigned char ch, flag;
1380 	unsigned short status;
1381 
1382 	/* While we can read, do so ! */
1383 	while (psc_ops->raw_rx_rdy(port)) {
1384 		/* Get the char */
1385 		ch = psc_ops->read_char(port);
1386 
1387 		/* Handle sysreq char */
1388 #ifdef SUPPORT_SYSRQ
1389 		if (uart_handle_sysrq_char(port, ch)) {
1390 			port->sysrq = 0;
1391 			continue;
1392 		}
1393 #endif
1394 
1395 		/* Store it */
1396 
1397 		flag = TTY_NORMAL;
1398 		port->icount.rx++;
1399 
1400 		status = psc_ops->get_status(port);
1401 
1402 		if (status & (MPC52xx_PSC_SR_PE |
1403 			      MPC52xx_PSC_SR_FE |
1404 			      MPC52xx_PSC_SR_RB)) {
1405 
1406 			if (status & MPC52xx_PSC_SR_RB) {
1407 				flag = TTY_BREAK;
1408 				uart_handle_break(port);
1409 				port->icount.brk++;
1410 			} else if (status & MPC52xx_PSC_SR_PE) {
1411 				flag = TTY_PARITY;
1412 				port->icount.parity++;
1413 			}
1414 			else if (status & MPC52xx_PSC_SR_FE) {
1415 				flag = TTY_FRAME;
1416 				port->icount.frame++;
1417 			}
1418 
1419 			/* Clear error condition */
1420 			psc_ops->command(port, MPC52xx_PSC_RST_ERR_STAT);
1421 
1422 		}
1423 		tty_insert_flip_char(tport, ch, flag);
1424 		if (status & MPC52xx_PSC_SR_OE) {
1425 			/*
1426 			 * Overrun is special, since it's
1427 			 * reported immediately, and doesn't
1428 			 * affect the current character
1429 			 */
1430 			tty_insert_flip_char(tport, 0, TTY_OVERRUN);
1431 			port->icount.overrun++;
1432 		}
1433 	}
1434 
1435 	spin_unlock(&port->lock);
1436 	tty_flip_buffer_push(tport);
1437 	spin_lock(&port->lock);
1438 
1439 	return psc_ops->raw_rx_rdy(port);
1440 }
1441 
1442 static inline int
1443 mpc52xx_uart_int_tx_chars(struct uart_port *port)
1444 {
1445 	struct circ_buf *xmit = &port->state->xmit;
1446 
1447 	/* Process out of band chars */
1448 	if (port->x_char) {
1449 		psc_ops->write_char(port, port->x_char);
1450 		port->icount.tx++;
1451 		port->x_char = 0;
1452 		return 1;
1453 	}
1454 
1455 	/* Nothing to do ? */
1456 	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
1457 		mpc52xx_uart_stop_tx(port);
1458 		return 0;
1459 	}
1460 
1461 	/* Send chars */
1462 	while (psc_ops->raw_tx_rdy(port)) {
1463 		psc_ops->write_char(port, xmit->buf[xmit->tail]);
1464 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
1465 		port->icount.tx++;
1466 		if (uart_circ_empty(xmit))
1467 			break;
1468 	}
1469 
1470 	/* Wake up */
1471 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1472 		uart_write_wakeup(port);
1473 
1474 	/* Maybe we're done after all */
1475 	if (uart_circ_empty(xmit)) {
1476 		mpc52xx_uart_stop_tx(port);
1477 		return 0;
1478 	}
1479 
1480 	return 1;
1481 }
1482 
1483 static irqreturn_t
1484 mpc5xxx_uart_process_int(struct uart_port *port)
1485 {
1486 	unsigned long pass = ISR_PASS_LIMIT;
1487 	unsigned int keepgoing;
1488 	u8 status;
1489 
1490 	/* While we have stuff to do, we continue */
1491 	do {
1492 		/* If we don't find anything to do, we stop */
1493 		keepgoing = 0;
1494 
1495 		psc_ops->rx_clr_irq(port);
1496 		if (psc_ops->rx_rdy(port))
1497 			keepgoing |= mpc52xx_uart_int_rx_chars(port);
1498 
1499 		psc_ops->tx_clr_irq(port);
1500 		if (psc_ops->tx_rdy(port))
1501 			keepgoing |= mpc52xx_uart_int_tx_chars(port);
1502 
1503 		status = psc_ops->get_ipcr(port);
1504 		if (status & MPC52xx_PSC_D_DCD)
1505 			uart_handle_dcd_change(port, !(status & MPC52xx_PSC_DCD));
1506 
1507 		if (status & MPC52xx_PSC_D_CTS)
1508 			uart_handle_cts_change(port, !(status & MPC52xx_PSC_CTS));
1509 
1510 		/* Limit number of iteration */
1511 		if (!(--pass))
1512 			keepgoing = 0;
1513 
1514 	} while (keepgoing);
1515 
1516 	return IRQ_HANDLED;
1517 }
1518 
1519 static irqreturn_t
1520 mpc52xx_uart_int(int irq, void *dev_id)
1521 {
1522 	struct uart_port *port = dev_id;
1523 	irqreturn_t ret;
1524 
1525 	spin_lock(&port->lock);
1526 
1527 	ret = psc_ops->handle_irq(port);
1528 
1529 	spin_unlock(&port->lock);
1530 
1531 	return ret;
1532 }
1533 
1534 /* ======================================================================== */
1535 /* Console ( if applicable )                                                */
1536 /* ======================================================================== */
1537 
1538 #ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
1539 
1540 static void __init
1541 mpc52xx_console_get_options(struct uart_port *port,
1542 			    int *baud, int *parity, int *bits, int *flow)
1543 {
1544 	unsigned char mr1;
1545 
1546 	pr_debug("mpc52xx_console_get_options(port=%p)\n", port);
1547 
1548 	/* Read the mode registers */
1549 	mr1 = psc_ops->get_mr1(port);
1550 
1551 	/* CT{U,L}R are write-only ! */
1552 	*baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1553 
1554 	/* Parse them */
1555 	switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
1556 	case MPC52xx_PSC_MODE_5_BITS:
1557 		*bits = 5;
1558 		break;
1559 	case MPC52xx_PSC_MODE_6_BITS:
1560 		*bits = 6;
1561 		break;
1562 	case MPC52xx_PSC_MODE_7_BITS:
1563 		*bits = 7;
1564 		break;
1565 	case MPC52xx_PSC_MODE_8_BITS:
1566 	default:
1567 		*bits = 8;
1568 	}
1569 
1570 	if (mr1 & MPC52xx_PSC_MODE_PARNONE)
1571 		*parity = 'n';
1572 	else
1573 		*parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
1574 }
1575 
1576 static void
1577 mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
1578 {
1579 	struct uart_port *port = &mpc52xx_uart_ports[co->index];
1580 	unsigned int i, j;
1581 
1582 	/* Disable interrupts */
1583 	psc_ops->cw_disable_ints(port);
1584 
1585 	/* Wait the TX buffer to be empty */
1586 	j = 5000000;	/* Maximum wait */
1587 	while (!mpc52xx_uart_tx_empty(port) && --j)
1588 		udelay(1);
1589 
1590 	/* Write all the chars */
1591 	for (i = 0; i < count; i++, s++) {
1592 		/* Line return handling */
1593 		if (*s == '\n')
1594 			psc_ops->write_char(port, '\r');
1595 
1596 		/* Send the char */
1597 		psc_ops->write_char(port, *s);
1598 
1599 		/* Wait the TX buffer to be empty */
1600 		j = 20000;	/* Maximum wait */
1601 		while (!mpc52xx_uart_tx_empty(port) && --j)
1602 			udelay(1);
1603 	}
1604 
1605 	/* Restore interrupt state */
1606 	psc_ops->cw_restore_ints(port);
1607 }
1608 
1609 
1610 static int __init
1611 mpc52xx_console_setup(struct console *co, char *options)
1612 {
1613 	struct uart_port *port = &mpc52xx_uart_ports[co->index];
1614 	struct device_node *np = mpc52xx_uart_nodes[co->index];
1615 	unsigned int uartclk;
1616 	struct resource res;
1617 	int ret;
1618 
1619 	int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1620 	int bits = 8;
1621 	int parity = 'n';
1622 	int flow = 'n';
1623 
1624 	pr_debug("mpc52xx_console_setup co=%p, co->index=%i, options=%s\n",
1625 		 co, co->index, options);
1626 
1627 	if ((co->index < 0) || (co->index >= MPC52xx_PSC_MAXNUM)) {
1628 		pr_debug("PSC%x out of range\n", co->index);
1629 		return -EINVAL;
1630 	}
1631 
1632 	if (!np) {
1633 		pr_debug("PSC%x not found in device tree\n", co->index);
1634 		return -EINVAL;
1635 	}
1636 
1637 	pr_debug("Console on ttyPSC%x is %s\n",
1638 		 co->index, mpc52xx_uart_nodes[co->index]->full_name);
1639 
1640 	/* Fetch register locations */
1641 	ret = of_address_to_resource(np, 0, &res);
1642 	if (ret) {
1643 		pr_debug("Could not get resources for PSC%x\n", co->index);
1644 		return ret;
1645 	}
1646 
1647 	uartclk = mpc5xxx_get_bus_frequency(np);
1648 	if (uartclk == 0) {
1649 		pr_debug("Could not find uart clock frequency!\n");
1650 		return -EINVAL;
1651 	}
1652 
1653 	/* Basic port init. Needed since we use some uart_??? func before
1654 	 * real init for early access */
1655 	spin_lock_init(&port->lock);
1656 	port->uartclk = uartclk;
1657 	port->ops	= &mpc52xx_uart_ops;
1658 	port->mapbase = res.start;
1659 	port->membase = ioremap(res.start, sizeof(struct mpc52xx_psc));
1660 	port->irq = irq_of_parse_and_map(np, 0);
1661 
1662 	if (port->membase == NULL)
1663 		return -EINVAL;
1664 
1665 	pr_debug("mpc52xx-psc uart at %p, mapped to %p, irq=%x, freq=%i\n",
1666 		 (void *)port->mapbase, port->membase,
1667 		 port->irq, port->uartclk);
1668 
1669 	/* Setup the port parameters accoding to options */
1670 	if (options)
1671 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1672 	else
1673 		mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
1674 
1675 	pr_debug("Setting console parameters: %i %i%c1 flow=%c\n",
1676 		 baud, bits, parity, flow);
1677 
1678 	return uart_set_options(port, co, baud, parity, bits, flow);
1679 }
1680 
1681 
1682 static struct uart_driver mpc52xx_uart_driver;
1683 
1684 static struct console mpc52xx_console = {
1685 	.name	= "ttyPSC",
1686 	.write	= mpc52xx_console_write,
1687 	.device	= uart_console_device,
1688 	.setup	= mpc52xx_console_setup,
1689 	.flags	= CON_PRINTBUFFER,
1690 	.index	= -1,	/* Specified on the cmdline (e.g. console=ttyPSC0) */
1691 	.data	= &mpc52xx_uart_driver,
1692 };
1693 
1694 
1695 static int __init
1696 mpc52xx_console_init(void)
1697 {
1698 	mpc52xx_uart_of_enumerate();
1699 	register_console(&mpc52xx_console);
1700 	return 0;
1701 }
1702 
1703 console_initcall(mpc52xx_console_init);
1704 
1705 #define MPC52xx_PSC_CONSOLE &mpc52xx_console
1706 #else
1707 #define MPC52xx_PSC_CONSOLE NULL
1708 #endif
1709 
1710 
1711 /* ======================================================================== */
1712 /* UART Driver                                                              */
1713 /* ======================================================================== */
1714 
1715 static struct uart_driver mpc52xx_uart_driver = {
1716 	.driver_name	= "mpc52xx_psc_uart",
1717 	.dev_name	= "ttyPSC",
1718 	.major		= SERIAL_PSC_MAJOR,
1719 	.minor		= SERIAL_PSC_MINOR,
1720 	.nr		= MPC52xx_PSC_MAXNUM,
1721 	.cons		= MPC52xx_PSC_CONSOLE,
1722 };
1723 
1724 /* ======================================================================== */
1725 /* OF Platform Driver                                                       */
1726 /* ======================================================================== */
1727 
1728 static const struct of_device_id mpc52xx_uart_of_match[] = {
1729 #ifdef CONFIG_PPC_MPC52xx
1730 	{ .compatible = "fsl,mpc5200b-psc-uart", .data = &mpc5200b_psc_ops, },
1731 	{ .compatible = "fsl,mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1732 	/* binding used by old lite5200 device trees: */
1733 	{ .compatible = "mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1734 	/* binding used by efika: */
1735 	{ .compatible = "mpc5200-serial", .data = &mpc52xx_psc_ops, },
1736 #endif
1737 #ifdef CONFIG_PPC_MPC512x
1738 	{ .compatible = "fsl,mpc5121-psc-uart", .data = &mpc512x_psc_ops, },
1739 	{ .compatible = "fsl,mpc5125-psc-uart", .data = &mpc5125_psc_ops, },
1740 #endif
1741 	{},
1742 };
1743 
1744 static int mpc52xx_uart_of_probe(struct platform_device *op)
1745 {
1746 	int idx = -1;
1747 	unsigned int uartclk;
1748 	struct uart_port *port = NULL;
1749 	struct resource res;
1750 	int ret;
1751 
1752 	/* Check validity & presence */
1753 	for (idx = 0; idx < MPC52xx_PSC_MAXNUM; idx++)
1754 		if (mpc52xx_uart_nodes[idx] == op->dev.of_node)
1755 			break;
1756 	if (idx >= MPC52xx_PSC_MAXNUM)
1757 		return -EINVAL;
1758 	pr_debug("Found %s assigned to ttyPSC%x\n",
1759 		 mpc52xx_uart_nodes[idx]->full_name, idx);
1760 
1761 	/* set the uart clock to the input clock of the psc, the different
1762 	 * prescalers are taken into account in the set_baudrate() methods
1763 	 * of the respective chip */
1764 	uartclk = mpc5xxx_get_bus_frequency(op->dev.of_node);
1765 	if (uartclk == 0) {
1766 		dev_dbg(&op->dev, "Could not find uart clock frequency!\n");
1767 		return -EINVAL;
1768 	}
1769 
1770 	/* Init the port structure */
1771 	port = &mpc52xx_uart_ports[idx];
1772 
1773 	spin_lock_init(&port->lock);
1774 	port->uartclk = uartclk;
1775 	port->fifosize	= 512;
1776 	port->iotype	= UPIO_MEM;
1777 	port->flags	= UPF_BOOT_AUTOCONF |
1778 			  (uart_console(port) ? 0 : UPF_IOREMAP);
1779 	port->line	= idx;
1780 	port->ops	= &mpc52xx_uart_ops;
1781 	port->dev	= &op->dev;
1782 
1783 	/* Search for IRQ and mapbase */
1784 	ret = of_address_to_resource(op->dev.of_node, 0, &res);
1785 	if (ret)
1786 		return ret;
1787 
1788 	port->mapbase = res.start;
1789 	if (!port->mapbase) {
1790 		dev_dbg(&op->dev, "Could not allocate resources for PSC\n");
1791 		return -EINVAL;
1792 	}
1793 
1794 	psc_ops->get_irq(port, op->dev.of_node);
1795 	if (port->irq == 0) {
1796 		dev_dbg(&op->dev, "Could not get irq\n");
1797 		return -EINVAL;
1798 	}
1799 
1800 	dev_dbg(&op->dev, "mpc52xx-psc uart at %p, irq=%x, freq=%i\n",
1801 		(void *)port->mapbase, port->irq, port->uartclk);
1802 
1803 	/* Add the port to the uart sub-system */
1804 	ret = uart_add_one_port(&mpc52xx_uart_driver, port);
1805 	if (ret)
1806 		return ret;
1807 
1808 	platform_set_drvdata(op, (void *)port);
1809 	return 0;
1810 }
1811 
1812 static int
1813 mpc52xx_uart_of_remove(struct platform_device *op)
1814 {
1815 	struct uart_port *port = platform_get_drvdata(op);
1816 
1817 	if (port)
1818 		uart_remove_one_port(&mpc52xx_uart_driver, port);
1819 
1820 	return 0;
1821 }
1822 
1823 #ifdef CONFIG_PM
1824 static int
1825 mpc52xx_uart_of_suspend(struct platform_device *op, pm_message_t state)
1826 {
1827 	struct uart_port *port = platform_get_drvdata(op);
1828 
1829 	if (port)
1830 		uart_suspend_port(&mpc52xx_uart_driver, port);
1831 
1832 	return 0;
1833 }
1834 
1835 static int
1836 mpc52xx_uart_of_resume(struct platform_device *op)
1837 {
1838 	struct uart_port *port = platform_get_drvdata(op);
1839 
1840 	if (port)
1841 		uart_resume_port(&mpc52xx_uart_driver, port);
1842 
1843 	return 0;
1844 }
1845 #endif
1846 
1847 static void
1848 mpc52xx_uart_of_assign(struct device_node *np)
1849 {
1850 	int i;
1851 
1852 	/* Find the first free PSC number */
1853 	for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1854 		if (mpc52xx_uart_nodes[i] == NULL) {
1855 			of_node_get(np);
1856 			mpc52xx_uart_nodes[i] = np;
1857 			return;
1858 		}
1859 	}
1860 }
1861 
1862 static void
1863 mpc52xx_uart_of_enumerate(void)
1864 {
1865 	static int enum_done;
1866 	struct device_node *np;
1867 	const struct  of_device_id *match;
1868 	int i;
1869 
1870 	if (enum_done)
1871 		return;
1872 
1873 	/* Assign index to each PSC in device tree */
1874 	for_each_matching_node(np, mpc52xx_uart_of_match) {
1875 		match = of_match_node(mpc52xx_uart_of_match, np);
1876 		psc_ops = match->data;
1877 		mpc52xx_uart_of_assign(np);
1878 	}
1879 
1880 	enum_done = 1;
1881 
1882 	for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1883 		if (mpc52xx_uart_nodes[i])
1884 			pr_debug("%s assigned to ttyPSC%x\n",
1885 				 mpc52xx_uart_nodes[i]->full_name, i);
1886 	}
1887 }
1888 
1889 MODULE_DEVICE_TABLE(of, mpc52xx_uart_of_match);
1890 
1891 static struct platform_driver mpc52xx_uart_of_driver = {
1892 	.probe		= mpc52xx_uart_of_probe,
1893 	.remove		= mpc52xx_uart_of_remove,
1894 #ifdef CONFIG_PM
1895 	.suspend	= mpc52xx_uart_of_suspend,
1896 	.resume		= mpc52xx_uart_of_resume,
1897 #endif
1898 	.driver = {
1899 		.name = "mpc52xx-psc-uart",
1900 		.of_match_table = mpc52xx_uart_of_match,
1901 	},
1902 };
1903 
1904 
1905 /* ======================================================================== */
1906 /* Module                                                                   */
1907 /* ======================================================================== */
1908 
1909 static int __init
1910 mpc52xx_uart_init(void)
1911 {
1912 	int ret;
1913 
1914 	printk(KERN_INFO "Serial: MPC52xx PSC UART driver\n");
1915 
1916 	ret = uart_register_driver(&mpc52xx_uart_driver);
1917 	if (ret) {
1918 		printk(KERN_ERR "%s: uart_register_driver failed (%i)\n",
1919 		       __FILE__, ret);
1920 		return ret;
1921 	}
1922 
1923 	mpc52xx_uart_of_enumerate();
1924 
1925 	/*
1926 	 * Map the PSC FIFO Controller and init if on MPC512x.
1927 	 */
1928 	if (psc_ops && psc_ops->fifoc_init) {
1929 		ret = psc_ops->fifoc_init();
1930 		if (ret)
1931 			goto err_init;
1932 	}
1933 
1934 	ret = platform_driver_register(&mpc52xx_uart_of_driver);
1935 	if (ret) {
1936 		printk(KERN_ERR "%s: platform_driver_register failed (%i)\n",
1937 		       __FILE__, ret);
1938 		goto err_reg;
1939 	}
1940 
1941 	return 0;
1942 err_reg:
1943 	if (psc_ops && psc_ops->fifoc_uninit)
1944 		psc_ops->fifoc_uninit();
1945 err_init:
1946 	uart_unregister_driver(&mpc52xx_uart_driver);
1947 	return ret;
1948 }
1949 
1950 static void __exit
1951 mpc52xx_uart_exit(void)
1952 {
1953 	if (psc_ops->fifoc_uninit)
1954 		psc_ops->fifoc_uninit();
1955 
1956 	platform_driver_unregister(&mpc52xx_uart_of_driver);
1957 	uart_unregister_driver(&mpc52xx_uart_driver);
1958 }
1959 
1960 
1961 module_init(mpc52xx_uart_init);
1962 module_exit(mpc52xx_uart_exit);
1963 
1964 MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
1965 MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
1966 MODULE_LICENSE("GPL");
1967