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 	return in_be16(&PSC(port)->mpc52xx_psc_status)
243 	    & MPC52xx_PSC_SR_TXEMP;
244 }
245 
246 static void mpc52xx_psc_start_tx(struct uart_port *port)
247 {
248 	port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
249 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
250 }
251 
252 static void mpc52xx_psc_stop_tx(struct uart_port *port)
253 {
254 	port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY;
255 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
256 }
257 
258 static void mpc52xx_psc_stop_rx(struct uart_port *port)
259 {
260 	port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY;
261 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
262 }
263 
264 static void mpc52xx_psc_rx_clr_irq(struct uart_port *port)
265 {
266 }
267 
268 static void mpc52xx_psc_tx_clr_irq(struct uart_port *port)
269 {
270 }
271 
272 static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char c)
273 {
274 	out_8(&PSC(port)->mpc52xx_psc_buffer_8, c);
275 }
276 
277 static unsigned char mpc52xx_psc_read_char(struct uart_port *port)
278 {
279 	return in_8(&PSC(port)->mpc52xx_psc_buffer_8);
280 }
281 
282 static void mpc52xx_psc_cw_disable_ints(struct uart_port *port)
283 {
284 	out_be16(&PSC(port)->mpc52xx_psc_imr, 0);
285 }
286 
287 static void mpc52xx_psc_cw_restore_ints(struct uart_port *port)
288 {
289 	out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
290 }
291 
292 static unsigned int mpc5200_psc_set_baudrate(struct uart_port *port,
293 					     struct ktermios *new,
294 					     struct ktermios *old)
295 {
296 	unsigned int baud;
297 	unsigned int divisor;
298 
299 	/* The 5200 has a fixed /32 prescaler, uartclk contains the ipb freq */
300 	baud = uart_get_baud_rate(port, new, old,
301 				  port->uartclk / (32 * 0xffff) + 1,
302 				  port->uartclk / 32);
303 	divisor = (port->uartclk + 16 * baud) / (32 * baud);
304 
305 	/* enable the /32 prescaler and set the divisor */
306 	mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
307 	return baud;
308 }
309 
310 static unsigned int mpc5200b_psc_set_baudrate(struct uart_port *port,
311 					      struct ktermios *new,
312 					      struct ktermios *old)
313 {
314 	unsigned int baud;
315 	unsigned int divisor;
316 	u16 prescaler;
317 
318 	/* The 5200B has a selectable /4 or /32 prescaler, uartclk contains the
319 	 * ipb freq */
320 	baud = uart_get_baud_rate(port, new, old,
321 				  port->uartclk / (32 * 0xffff) + 1,
322 				  port->uartclk / 4);
323 	divisor = (port->uartclk + 2 * baud) / (4 * baud);
324 
325 	/* select the proper prescaler and set the divisor
326 	 * prefer high prescaler for more tolerance on low baudrates */
327 	if (divisor > 0xffff || baud <= 115200) {
328 		divisor = (divisor + 4) / 8;
329 		prescaler = 0xdd00; /* /32 */
330 	} else
331 		prescaler = 0xff00; /* /4 */
332 	mpc52xx_set_divisor(PSC(port), prescaler, divisor);
333 	return baud;
334 }
335 
336 static void mpc52xx_psc_get_irq(struct uart_port *port, struct device_node *np)
337 {
338 	port->irqflags = 0;
339 	port->irq = irq_of_parse_and_map(np, 0);
340 }
341 
342 /* 52xx specific interrupt handler. The caller holds the port lock */
343 static irqreturn_t mpc52xx_psc_handle_irq(struct uart_port *port)
344 {
345 	return mpc5xxx_uart_process_int(port);
346 }
347 
348 static struct psc_ops mpc52xx_psc_ops = {
349 	.fifo_init = mpc52xx_psc_fifo_init,
350 	.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
351 	.raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
352 	.rx_rdy = mpc52xx_psc_rx_rdy,
353 	.tx_rdy = mpc52xx_psc_tx_rdy,
354 	.tx_empty = mpc52xx_psc_tx_empty,
355 	.stop_rx = mpc52xx_psc_stop_rx,
356 	.start_tx = mpc52xx_psc_start_tx,
357 	.stop_tx = mpc52xx_psc_stop_tx,
358 	.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
359 	.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
360 	.write_char = mpc52xx_psc_write_char,
361 	.read_char = mpc52xx_psc_read_char,
362 	.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
363 	.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
364 	.set_baudrate = mpc5200_psc_set_baudrate,
365 	.get_irq = mpc52xx_psc_get_irq,
366 	.handle_irq = mpc52xx_psc_handle_irq,
367 	.get_status = mpc52xx_psc_get_status,
368 	.get_ipcr = mpc52xx_psc_get_ipcr,
369 	.command = mpc52xx_psc_command,
370 	.set_mode = mpc52xx_psc_set_mode,
371 	.set_rts = mpc52xx_psc_set_rts,
372 	.enable_ms = mpc52xx_psc_enable_ms,
373 	.set_sicr = mpc52xx_psc_set_sicr,
374 	.set_imr = mpc52xx_psc_set_imr,
375 	.get_mr1 = mpc52xx_psc_get_mr1,
376 };
377 
378 static struct psc_ops mpc5200b_psc_ops = {
379 	.fifo_init = mpc52xx_psc_fifo_init,
380 	.raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
381 	.raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
382 	.rx_rdy = mpc52xx_psc_rx_rdy,
383 	.tx_rdy = mpc52xx_psc_tx_rdy,
384 	.tx_empty = mpc52xx_psc_tx_empty,
385 	.stop_rx = mpc52xx_psc_stop_rx,
386 	.start_tx = mpc52xx_psc_start_tx,
387 	.stop_tx = mpc52xx_psc_stop_tx,
388 	.rx_clr_irq = mpc52xx_psc_rx_clr_irq,
389 	.tx_clr_irq = mpc52xx_psc_tx_clr_irq,
390 	.write_char = mpc52xx_psc_write_char,
391 	.read_char = mpc52xx_psc_read_char,
392 	.cw_disable_ints = mpc52xx_psc_cw_disable_ints,
393 	.cw_restore_ints = mpc52xx_psc_cw_restore_ints,
394 	.set_baudrate = mpc5200b_psc_set_baudrate,
395 	.get_irq = mpc52xx_psc_get_irq,
396 	.handle_irq = mpc52xx_psc_handle_irq,
397 	.get_status = mpc52xx_psc_get_status,
398 	.get_ipcr = mpc52xx_psc_get_ipcr,
399 	.command = mpc52xx_psc_command,
400 	.set_mode = mpc52xx_psc_set_mode,
401 	.set_rts = mpc52xx_psc_set_rts,
402 	.enable_ms = mpc52xx_psc_enable_ms,
403 	.set_sicr = mpc52xx_psc_set_sicr,
404 	.set_imr = mpc52xx_psc_set_imr,
405 	.get_mr1 = mpc52xx_psc_get_mr1,
406 };
407 
408 #endif /* CONFIG_MPC52xx */
409 
410 #ifdef CONFIG_PPC_MPC512x
411 #define FIFO_512x(port) ((struct mpc512x_psc_fifo __iomem *)(PSC(port)+1))
412 
413 /* PSC FIFO Controller for mpc512x */
414 struct psc_fifoc {
415 	u32 fifoc_cmd;
416 	u32 fifoc_int;
417 	u32 fifoc_dma;
418 	u32 fifoc_axe;
419 	u32 fifoc_debug;
420 };
421 
422 static struct psc_fifoc __iomem *psc_fifoc;
423 static unsigned int psc_fifoc_irq;
424 static struct clk *psc_fifoc_clk;
425 
426 static void mpc512x_psc_fifo_init(struct uart_port *port)
427 {
428 	/* /32 prescaler */
429 	out_be16(&PSC(port)->mpc52xx_psc_clock_select, 0xdd00);
430 
431 	out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
432 	out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
433 	out_be32(&FIFO_512x(port)->txalarm, 1);
434 	out_be32(&FIFO_512x(port)->tximr, 0);
435 
436 	out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
437 	out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
438 	out_be32(&FIFO_512x(port)->rxalarm, 1);
439 	out_be32(&FIFO_512x(port)->rximr, 0);
440 
441 	out_be32(&FIFO_512x(port)->tximr, MPC512x_PSC_FIFO_ALARM);
442 	out_be32(&FIFO_512x(port)->rximr, MPC512x_PSC_FIFO_ALARM);
443 }
444 
445 static int mpc512x_psc_raw_rx_rdy(struct uart_port *port)
446 {
447 	return !(in_be32(&FIFO_512x(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
448 }
449 
450 static int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
451 {
452 	return !(in_be32(&FIFO_512x(port)->txsr) & MPC512x_PSC_FIFO_FULL);
453 }
454 
455 static int mpc512x_psc_rx_rdy(struct uart_port *port)
456 {
457 	return in_be32(&FIFO_512x(port)->rxsr)
458 	    & in_be32(&FIFO_512x(port)->rximr)
459 	    & MPC512x_PSC_FIFO_ALARM;
460 }
461 
462 static int mpc512x_psc_tx_rdy(struct uart_port *port)
463 {
464 	return in_be32(&FIFO_512x(port)->txsr)
465 	    & in_be32(&FIFO_512x(port)->tximr)
466 	    & MPC512x_PSC_FIFO_ALARM;
467 }
468 
469 static int mpc512x_psc_tx_empty(struct uart_port *port)
470 {
471 	return in_be32(&FIFO_512x(port)->txsr)
472 	    & MPC512x_PSC_FIFO_EMPTY;
473 }
474 
475 static void mpc512x_psc_stop_rx(struct uart_port *port)
476 {
477 	unsigned long rx_fifo_imr;
478 
479 	rx_fifo_imr = in_be32(&FIFO_512x(port)->rximr);
480 	rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
481 	out_be32(&FIFO_512x(port)->rximr, rx_fifo_imr);
482 }
483 
484 static void mpc512x_psc_start_tx(struct uart_port *port)
485 {
486 	unsigned long tx_fifo_imr;
487 
488 	tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
489 	tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
490 	out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
491 }
492 
493 static void mpc512x_psc_stop_tx(struct uart_port *port)
494 {
495 	unsigned long tx_fifo_imr;
496 
497 	tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
498 	tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
499 	out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
500 }
501 
502 static void mpc512x_psc_rx_clr_irq(struct uart_port *port)
503 {
504 	out_be32(&FIFO_512x(port)->rxisr, in_be32(&FIFO_512x(port)->rxisr));
505 }
506 
507 static void mpc512x_psc_tx_clr_irq(struct uart_port *port)
508 {
509 	out_be32(&FIFO_512x(port)->txisr, in_be32(&FIFO_512x(port)->txisr));
510 }
511 
512 static void mpc512x_psc_write_char(struct uart_port *port, unsigned char c)
513 {
514 	out_8(&FIFO_512x(port)->txdata_8, c);
515 }
516 
517 static unsigned char mpc512x_psc_read_char(struct uart_port *port)
518 {
519 	return in_8(&FIFO_512x(port)->rxdata_8);
520 }
521 
522 static void mpc512x_psc_cw_disable_ints(struct uart_port *port)
523 {
524 	port->read_status_mask =
525 		in_be32(&FIFO_512x(port)->tximr) << 16 |
526 		in_be32(&FIFO_512x(port)->rximr);
527 	out_be32(&FIFO_512x(port)->tximr, 0);
528 	out_be32(&FIFO_512x(port)->rximr, 0);
529 }
530 
531 static void mpc512x_psc_cw_restore_ints(struct uart_port *port)
532 {
533 	out_be32(&FIFO_512x(port)->tximr,
534 		(port->read_status_mask >> 16) & 0x7f);
535 	out_be32(&FIFO_512x(port)->rximr, port->read_status_mask & 0x7f);
536 }
537 
538 static unsigned int mpc512x_psc_set_baudrate(struct uart_port *port,
539 					     struct ktermios *new,
540 					     struct ktermios *old)
541 {
542 	unsigned int baud;
543 	unsigned int divisor;
544 
545 	/*
546 	 * The "MPC5121e Microcontroller Reference Manual, Rev. 3" says on
547 	 * pg. 30-10 that the chip supports a /32 and a /10 prescaler.
548 	 * Furthermore, it states that "After reset, the prescaler by 10
549 	 * for the UART mode is selected", but the reset register value is
550 	 * 0x0000 which means a /32 prescaler. This is wrong.
551 	 *
552 	 * In reality using /32 prescaler doesn't work, as it is not supported!
553 	 * Use /16 or /10 prescaler, see "MPC5121e Hardware Design Guide",
554 	 * Chapter 4.1 PSC in UART Mode.
555 	 * Calculate with a /16 prescaler here.
556 	 */
557 
558 	/* uartclk contains the ips freq */
559 	baud = uart_get_baud_rate(port, new, old,
560 				  port->uartclk / (16 * 0xffff) + 1,
561 				  port->uartclk / 16);
562 	divisor = (port->uartclk + 8 * baud) / (16 * baud);
563 
564 	/* enable the /16 prescaler and set the divisor */
565 	mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
566 	return baud;
567 }
568 
569 /* Init PSC FIFO Controller */
570 static int __init mpc512x_psc_fifoc_init(void)
571 {
572 	int err;
573 	struct device_node *np;
574 	struct clk *clk;
575 
576 	/* default error code, potentially overwritten by clock calls */
577 	err = -ENODEV;
578 
579 	np = of_find_compatible_node(NULL, NULL,
580 				     "fsl,mpc5121-psc-fifo");
581 	if (!np) {
582 		pr_err("%s: Can't find FIFOC node\n", __func__);
583 		goto out_err;
584 	}
585 
586 	clk = of_clk_get(np, 0);
587 	if (IS_ERR(clk)) {
588 		/* backwards compat with device trees that lack clock specs */
589 		clk = clk_get_sys(np->name, "ipg");
590 	}
591 	if (IS_ERR(clk)) {
592 		pr_err("%s: Can't lookup FIFO clock\n", __func__);
593 		err = PTR_ERR(clk);
594 		goto out_ofnode_put;
595 	}
596 	if (clk_prepare_enable(clk)) {
597 		pr_err("%s: Can't enable FIFO clock\n", __func__);
598 		clk_put(clk);
599 		goto out_ofnode_put;
600 	}
601 	psc_fifoc_clk = clk;
602 
603 	psc_fifoc = of_iomap(np, 0);
604 	if (!psc_fifoc) {
605 		pr_err("%s: Can't map FIFOC\n", __func__);
606 		goto out_clk_disable;
607 	}
608 
609 	psc_fifoc_irq = irq_of_parse_and_map(np, 0);
610 	if (psc_fifoc_irq == 0) {
611 		pr_err("%s: Can't get FIFOC irq\n", __func__);
612 		goto out_unmap;
613 	}
614 
615 	of_node_put(np);
616 	return 0;
617 
618 out_unmap:
619 	iounmap(psc_fifoc);
620 out_clk_disable:
621 	clk_disable_unprepare(psc_fifoc_clk);
622 	clk_put(psc_fifoc_clk);
623 out_ofnode_put:
624 	of_node_put(np);
625 out_err:
626 	return err;
627 }
628 
629 static void __exit mpc512x_psc_fifoc_uninit(void)
630 {
631 	iounmap(psc_fifoc);
632 
633 	/* disable the clock, errors are not fatal */
634 	if (psc_fifoc_clk) {
635 		clk_disable_unprepare(psc_fifoc_clk);
636 		clk_put(psc_fifoc_clk);
637 		psc_fifoc_clk = NULL;
638 	}
639 }
640 
641 /* 512x specific interrupt handler. The caller holds the port lock */
642 static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port)
643 {
644 	unsigned long fifoc_int;
645 	int psc_num;
646 
647 	/* Read pending PSC FIFOC interrupts */
648 	fifoc_int = in_be32(&psc_fifoc->fifoc_int);
649 
650 	/* Check if it is an interrupt for this port */
651 	psc_num = (port->mapbase & 0xf00) >> 8;
652 	if (test_bit(psc_num, &fifoc_int) ||
653 	    test_bit(psc_num + 16, &fifoc_int))
654 		return mpc5xxx_uart_process_int(port);
655 
656 	return IRQ_NONE;
657 }
658 
659 static struct clk *psc_mclk_clk[MPC52xx_PSC_MAXNUM];
660 static struct clk *psc_ipg_clk[MPC52xx_PSC_MAXNUM];
661 
662 /* called from within the .request_port() callback (allocation) */
663 static int mpc512x_psc_alloc_clock(struct uart_port *port)
664 {
665 	int psc_num;
666 	struct clk *clk;
667 	int err;
668 
669 	psc_num = (port->mapbase & 0xf00) >> 8;
670 
671 	clk = devm_clk_get(port->dev, "mclk");
672 	if (IS_ERR(clk)) {
673 		dev_err(port->dev, "Failed to get MCLK!\n");
674 		err = PTR_ERR(clk);
675 		goto out_err;
676 	}
677 	err = clk_prepare_enable(clk);
678 	if (err) {
679 		dev_err(port->dev, "Failed to enable MCLK!\n");
680 		goto out_err;
681 	}
682 	psc_mclk_clk[psc_num] = clk;
683 
684 	clk = devm_clk_get(port->dev, "ipg");
685 	if (IS_ERR(clk)) {
686 		dev_err(port->dev, "Failed to get IPG clock!\n");
687 		err = PTR_ERR(clk);
688 		goto out_err;
689 	}
690 	err = clk_prepare_enable(clk);
691 	if (err) {
692 		dev_err(port->dev, "Failed to enable IPG clock!\n");
693 		goto out_err;
694 	}
695 	psc_ipg_clk[psc_num] = clk;
696 
697 	return 0;
698 
699 out_err:
700 	if (psc_mclk_clk[psc_num]) {
701 		clk_disable_unprepare(psc_mclk_clk[psc_num]);
702 		psc_mclk_clk[psc_num] = NULL;
703 	}
704 	if (psc_ipg_clk[psc_num]) {
705 		clk_disable_unprepare(psc_ipg_clk[psc_num]);
706 		psc_ipg_clk[psc_num] = NULL;
707 	}
708 	return err;
709 }
710 
711 /* called from within the .release_port() callback (release) */
712 static void mpc512x_psc_relse_clock(struct uart_port *port)
713 {
714 	int psc_num;
715 	struct clk *clk;
716 
717 	psc_num = (port->mapbase & 0xf00) >> 8;
718 	clk = psc_mclk_clk[psc_num];
719 	if (clk) {
720 		clk_disable_unprepare(clk);
721 		psc_mclk_clk[psc_num] = NULL;
722 	}
723 	if (psc_ipg_clk[psc_num]) {
724 		clk_disable_unprepare(psc_ipg_clk[psc_num]);
725 		psc_ipg_clk[psc_num] = NULL;
726 	}
727 }
728 
729 /* implementation of the .clock() callback (enable/disable) */
730 static int mpc512x_psc_endis_clock(struct uart_port *port, int enable)
731 {
732 	int psc_num;
733 	struct clk *psc_clk;
734 	int ret;
735 
736 	if (uart_console(port))
737 		return 0;
738 
739 	psc_num = (port->mapbase & 0xf00) >> 8;
740 	psc_clk = psc_mclk_clk[psc_num];
741 	if (!psc_clk) {
742 		dev_err(port->dev, "Failed to get PSC clock entry!\n");
743 		return -ENODEV;
744 	}
745 
746 	dev_dbg(port->dev, "mclk %sable\n", enable ? "en" : "dis");
747 	if (enable) {
748 		ret = clk_enable(psc_clk);
749 		if (ret)
750 			dev_err(port->dev, "Failed to enable MCLK!\n");
751 		return ret;
752 	} else {
753 		clk_disable(psc_clk);
754 		return 0;
755 	}
756 }
757 
758 static void mpc512x_psc_get_irq(struct uart_port *port, struct device_node *np)
759 {
760 	port->irqflags = IRQF_SHARED;
761 	port->irq = psc_fifoc_irq;
762 }
763 #endif
764 
765 #ifdef CONFIG_PPC_MPC512x
766 
767 #define PSC_5125(port) ((struct mpc5125_psc __iomem *)((port)->membase))
768 #define FIFO_5125(port) ((struct mpc512x_psc_fifo __iomem *)(PSC_5125(port)+1))
769 
770 static void mpc5125_psc_fifo_init(struct uart_port *port)
771 {
772 	/* /32 prescaler */
773 	out_8(&PSC_5125(port)->mpc52xx_psc_clock_select, 0xdd);
774 
775 	out_be32(&FIFO_5125(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
776 	out_be32(&FIFO_5125(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
777 	out_be32(&FIFO_5125(port)->txalarm, 1);
778 	out_be32(&FIFO_5125(port)->tximr, 0);
779 
780 	out_be32(&FIFO_5125(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
781 	out_be32(&FIFO_5125(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
782 	out_be32(&FIFO_5125(port)->rxalarm, 1);
783 	out_be32(&FIFO_5125(port)->rximr, 0);
784 
785 	out_be32(&FIFO_5125(port)->tximr, MPC512x_PSC_FIFO_ALARM);
786 	out_be32(&FIFO_5125(port)->rximr, MPC512x_PSC_FIFO_ALARM);
787 }
788 
789 static int mpc5125_psc_raw_rx_rdy(struct uart_port *port)
790 {
791 	return !(in_be32(&FIFO_5125(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
792 }
793 
794 static int mpc5125_psc_raw_tx_rdy(struct uart_port *port)
795 {
796 	return !(in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_FULL);
797 }
798 
799 static int mpc5125_psc_rx_rdy(struct uart_port *port)
800 {
801 	return in_be32(&FIFO_5125(port)->rxsr) &
802 	       in_be32(&FIFO_5125(port)->rximr) & MPC512x_PSC_FIFO_ALARM;
803 }
804 
805 static int mpc5125_psc_tx_rdy(struct uart_port *port)
806 {
807 	return in_be32(&FIFO_5125(port)->txsr) &
808 	       in_be32(&FIFO_5125(port)->tximr) & MPC512x_PSC_FIFO_ALARM;
809 }
810 
811 static int mpc5125_psc_tx_empty(struct uart_port *port)
812 {
813 	return in_be32(&FIFO_5125(port)->txsr) & MPC512x_PSC_FIFO_EMPTY;
814 }
815 
816 static void mpc5125_psc_stop_rx(struct uart_port *port)
817 {
818 	unsigned long rx_fifo_imr;
819 
820 	rx_fifo_imr = in_be32(&FIFO_5125(port)->rximr);
821 	rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
822 	out_be32(&FIFO_5125(port)->rximr, rx_fifo_imr);
823 }
824 
825 static void mpc5125_psc_start_tx(struct uart_port *port)
826 {
827 	unsigned long tx_fifo_imr;
828 
829 	tx_fifo_imr = in_be32(&FIFO_5125(port)->tximr);
830 	tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
831 	out_be32(&FIFO_5125(port)->tximr, tx_fifo_imr);
832 }
833 
834 static void mpc5125_psc_stop_tx(struct uart_port *port)
835 {
836 	unsigned long tx_fifo_imr;
837 
838 	tx_fifo_imr = in_be32(&FIFO_5125(port)->tximr);
839 	tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
840 	out_be32(&FIFO_5125(port)->tximr, tx_fifo_imr);
841 }
842 
843 static void mpc5125_psc_rx_clr_irq(struct uart_port *port)
844 {
845 	out_be32(&FIFO_5125(port)->rxisr, in_be32(&FIFO_5125(port)->rxisr));
846 }
847 
848 static void mpc5125_psc_tx_clr_irq(struct uart_port *port)
849 {
850 	out_be32(&FIFO_5125(port)->txisr, in_be32(&FIFO_5125(port)->txisr));
851 }
852 
853 static void mpc5125_psc_write_char(struct uart_port *port, unsigned char c)
854 {
855 	out_8(&FIFO_5125(port)->txdata_8, c);
856 }
857 
858 static unsigned char mpc5125_psc_read_char(struct uart_port *port)
859 {
860 	return in_8(&FIFO_5125(port)->rxdata_8);
861 }
862 
863 static void mpc5125_psc_cw_disable_ints(struct uart_port *port)
864 {
865 	port->read_status_mask =
866 		in_be32(&FIFO_5125(port)->tximr) << 16 |
867 		in_be32(&FIFO_5125(port)->rximr);
868 	out_be32(&FIFO_5125(port)->tximr, 0);
869 	out_be32(&FIFO_5125(port)->rximr, 0);
870 }
871 
872 static void mpc5125_psc_cw_restore_ints(struct uart_port *port)
873 {
874 	out_be32(&FIFO_5125(port)->tximr,
875 		(port->read_status_mask >> 16) & 0x7f);
876 	out_be32(&FIFO_5125(port)->rximr, port->read_status_mask & 0x7f);
877 }
878 
879 static inline void mpc5125_set_divisor(struct mpc5125_psc __iomem *psc,
880 		u8 prescaler, unsigned int divisor)
881 {
882 	/* select prescaler */
883 	out_8(&psc->mpc52xx_psc_clock_select, prescaler);
884 	out_8(&psc->ctur, divisor >> 8);
885 	out_8(&psc->ctlr, divisor & 0xff);
886 }
887 
888 static unsigned int mpc5125_psc_set_baudrate(struct uart_port *port,
889 					     struct ktermios *new,
890 					     struct ktermios *old)
891 {
892 	unsigned int baud;
893 	unsigned int divisor;
894 
895 	/*
896 	 * Calculate with a /16 prescaler here.
897 	 */
898 
899 	/* uartclk contains the ips freq */
900 	baud = uart_get_baud_rate(port, new, old,
901 				  port->uartclk / (16 * 0xffff) + 1,
902 				  port->uartclk / 16);
903 	divisor = (port->uartclk + 8 * baud) / (16 * baud);
904 
905 	/* enable the /16 prescaler and set the divisor */
906 	mpc5125_set_divisor(PSC_5125(port), 0xdd, divisor);
907 	return baud;
908 }
909 
910 /*
911  * MPC5125 have compatible PSC FIFO Controller.
912  * Special init not needed.
913  */
914 static u16 mpc5125_psc_get_status(struct uart_port *port)
915 {
916 	return in_be16(&PSC_5125(port)->mpc52xx_psc_status);
917 }
918 
919 static u8 mpc5125_psc_get_ipcr(struct uart_port *port)
920 {
921 	return in_8(&PSC_5125(port)->mpc52xx_psc_ipcr);
922 }
923 
924 static void mpc5125_psc_command(struct uart_port *port, u8 cmd)
925 {
926 	out_8(&PSC_5125(port)->command, cmd);
927 }
928 
929 static void mpc5125_psc_set_mode(struct uart_port *port, u8 mr1, u8 mr2)
930 {
931 	out_8(&PSC_5125(port)->mr1, mr1);
932 	out_8(&PSC_5125(port)->mr2, mr2);
933 }
934 
935 static void mpc5125_psc_set_rts(struct uart_port *port, int state)
936 {
937 	if (state & TIOCM_RTS)
938 		out_8(&PSC_5125(port)->op1, MPC52xx_PSC_OP_RTS);
939 	else
940 		out_8(&PSC_5125(port)->op0, MPC52xx_PSC_OP_RTS);
941 }
942 
943 static void mpc5125_psc_enable_ms(struct uart_port *port)
944 {
945 	struct mpc5125_psc __iomem *psc = PSC_5125(port);
946 
947 	/* clear D_*-bits by reading them */
948 	in_8(&psc->mpc52xx_psc_ipcr);
949 	/* enable CTS and DCD as IPC interrupts */
950 	out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD);
951 
952 	port->read_status_mask |= MPC52xx_PSC_IMR_IPC;
953 	out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
954 }
955 
956 static void mpc5125_psc_set_sicr(struct uart_port *port, u32 val)
957 {
958 	out_be32(&PSC_5125(port)->sicr, val);
959 }
960 
961 static void mpc5125_psc_set_imr(struct uart_port *port, u16 val)
962 {
963 	out_be16(&PSC_5125(port)->mpc52xx_psc_imr, val);
964 }
965 
966 static u8 mpc5125_psc_get_mr1(struct uart_port *port)
967 {
968 	return in_8(&PSC_5125(port)->mr1);
969 }
970 
971 static struct psc_ops mpc5125_psc_ops = {
972 	.fifo_init = mpc5125_psc_fifo_init,
973 	.raw_rx_rdy = mpc5125_psc_raw_rx_rdy,
974 	.raw_tx_rdy = mpc5125_psc_raw_tx_rdy,
975 	.rx_rdy = mpc5125_psc_rx_rdy,
976 	.tx_rdy = mpc5125_psc_tx_rdy,
977 	.tx_empty = mpc5125_psc_tx_empty,
978 	.stop_rx = mpc5125_psc_stop_rx,
979 	.start_tx = mpc5125_psc_start_tx,
980 	.stop_tx = mpc5125_psc_stop_tx,
981 	.rx_clr_irq = mpc5125_psc_rx_clr_irq,
982 	.tx_clr_irq = mpc5125_psc_tx_clr_irq,
983 	.write_char = mpc5125_psc_write_char,
984 	.read_char = mpc5125_psc_read_char,
985 	.cw_disable_ints = mpc5125_psc_cw_disable_ints,
986 	.cw_restore_ints = mpc5125_psc_cw_restore_ints,
987 	.set_baudrate = mpc5125_psc_set_baudrate,
988 	.clock_alloc = mpc512x_psc_alloc_clock,
989 	.clock_relse = mpc512x_psc_relse_clock,
990 	.clock = mpc512x_psc_endis_clock,
991 	.fifoc_init = mpc512x_psc_fifoc_init,
992 	.fifoc_uninit = mpc512x_psc_fifoc_uninit,
993 	.get_irq = mpc512x_psc_get_irq,
994 	.handle_irq = mpc512x_psc_handle_irq,
995 	.get_status = mpc5125_psc_get_status,
996 	.get_ipcr = mpc5125_psc_get_ipcr,
997 	.command = mpc5125_psc_command,
998 	.set_mode = mpc5125_psc_set_mode,
999 	.set_rts = mpc5125_psc_set_rts,
1000 	.enable_ms = mpc5125_psc_enable_ms,
1001 	.set_sicr = mpc5125_psc_set_sicr,
1002 	.set_imr = mpc5125_psc_set_imr,
1003 	.get_mr1 = mpc5125_psc_get_mr1,
1004 };
1005 
1006 static struct psc_ops mpc512x_psc_ops = {
1007 	.fifo_init = mpc512x_psc_fifo_init,
1008 	.raw_rx_rdy = mpc512x_psc_raw_rx_rdy,
1009 	.raw_tx_rdy = mpc512x_psc_raw_tx_rdy,
1010 	.rx_rdy = mpc512x_psc_rx_rdy,
1011 	.tx_rdy = mpc512x_psc_tx_rdy,
1012 	.tx_empty = mpc512x_psc_tx_empty,
1013 	.stop_rx = mpc512x_psc_stop_rx,
1014 	.start_tx = mpc512x_psc_start_tx,
1015 	.stop_tx = mpc512x_psc_stop_tx,
1016 	.rx_clr_irq = mpc512x_psc_rx_clr_irq,
1017 	.tx_clr_irq = mpc512x_psc_tx_clr_irq,
1018 	.write_char = mpc512x_psc_write_char,
1019 	.read_char = mpc512x_psc_read_char,
1020 	.cw_disable_ints = mpc512x_psc_cw_disable_ints,
1021 	.cw_restore_ints = mpc512x_psc_cw_restore_ints,
1022 	.set_baudrate = mpc512x_psc_set_baudrate,
1023 	.clock_alloc = mpc512x_psc_alloc_clock,
1024 	.clock_relse = mpc512x_psc_relse_clock,
1025 	.clock = mpc512x_psc_endis_clock,
1026 	.fifoc_init = mpc512x_psc_fifoc_init,
1027 	.fifoc_uninit = mpc512x_psc_fifoc_uninit,
1028 	.get_irq = mpc512x_psc_get_irq,
1029 	.handle_irq = mpc512x_psc_handle_irq,
1030 	.get_status = mpc52xx_psc_get_status,
1031 	.get_ipcr = mpc52xx_psc_get_ipcr,
1032 	.command = mpc52xx_psc_command,
1033 	.set_mode = mpc52xx_psc_set_mode,
1034 	.set_rts = mpc52xx_psc_set_rts,
1035 	.enable_ms = mpc52xx_psc_enable_ms,
1036 	.set_sicr = mpc52xx_psc_set_sicr,
1037 	.set_imr = mpc52xx_psc_set_imr,
1038 	.get_mr1 = mpc52xx_psc_get_mr1,
1039 };
1040 #endif /* CONFIG_PPC_MPC512x */
1041 
1042 
1043 static const struct psc_ops *psc_ops;
1044 
1045 /* ======================================================================== */
1046 /* UART operations                                                          */
1047 /* ======================================================================== */
1048 
1049 static unsigned int
1050 mpc52xx_uart_tx_empty(struct uart_port *port)
1051 {
1052 	return psc_ops->tx_empty(port) ? TIOCSER_TEMT : 0;
1053 }
1054 
1055 static void
1056 mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1057 {
1058 	psc_ops->set_rts(port, mctrl & TIOCM_RTS);
1059 }
1060 
1061 static unsigned int
1062 mpc52xx_uart_get_mctrl(struct uart_port *port)
1063 {
1064 	unsigned int ret = TIOCM_DSR;
1065 	u8 status = psc_ops->get_ipcr(port);
1066 
1067 	if (!(status & MPC52xx_PSC_CTS))
1068 		ret |= TIOCM_CTS;
1069 	if (!(status & MPC52xx_PSC_DCD))
1070 		ret |= TIOCM_CAR;
1071 
1072 	return ret;
1073 }
1074 
1075 static void
1076 mpc52xx_uart_stop_tx(struct uart_port *port)
1077 {
1078 	/* port->lock taken by caller */
1079 	psc_ops->stop_tx(port);
1080 }
1081 
1082 static void
1083 mpc52xx_uart_start_tx(struct uart_port *port)
1084 {
1085 	/* port->lock taken by caller */
1086 	psc_ops->start_tx(port);
1087 }
1088 
1089 static void
1090 mpc52xx_uart_stop_rx(struct uart_port *port)
1091 {
1092 	/* port->lock taken by caller */
1093 	psc_ops->stop_rx(port);
1094 }
1095 
1096 static void
1097 mpc52xx_uart_enable_ms(struct uart_port *port)
1098 {
1099 	psc_ops->enable_ms(port);
1100 }
1101 
1102 static void
1103 mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
1104 {
1105 	unsigned long flags;
1106 	spin_lock_irqsave(&port->lock, flags);
1107 
1108 	if (ctl == -1)
1109 		psc_ops->command(port, MPC52xx_PSC_START_BRK);
1110 	else
1111 		psc_ops->command(port, MPC52xx_PSC_STOP_BRK);
1112 
1113 	spin_unlock_irqrestore(&port->lock, flags);
1114 }
1115 
1116 static int
1117 mpc52xx_uart_startup(struct uart_port *port)
1118 {
1119 	int ret;
1120 
1121 	if (psc_ops->clock) {
1122 		ret = psc_ops->clock(port, 1);
1123 		if (ret)
1124 			return ret;
1125 	}
1126 
1127 	/* Request IRQ */
1128 	ret = request_irq(port->irq, mpc52xx_uart_int,
1129 			  port->irqflags, "mpc52xx_psc_uart", port);
1130 	if (ret)
1131 		return ret;
1132 
1133 	/* Reset/activate the port, clear and enable interrupts */
1134 	psc_ops->command(port, MPC52xx_PSC_RST_RX);
1135 	psc_ops->command(port, MPC52xx_PSC_RST_TX);
1136 
1137 	psc_ops->set_sicr(port, 0);	/* UART mode DCD ignored */
1138 
1139 	psc_ops->fifo_init(port);
1140 
1141 	psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
1142 	psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
1143 
1144 	return 0;
1145 }
1146 
1147 static void
1148 mpc52xx_uart_shutdown(struct uart_port *port)
1149 {
1150 	/* Shut down the port.  Leave TX active if on a console port */
1151 	psc_ops->command(port, MPC52xx_PSC_RST_RX);
1152 	if (!uart_console(port))
1153 		psc_ops->command(port, MPC52xx_PSC_RST_TX);
1154 
1155 	port->read_status_mask = 0;
1156 	psc_ops->set_imr(port, port->read_status_mask);
1157 
1158 	if (psc_ops->clock)
1159 		psc_ops->clock(port, 0);
1160 
1161 	/* Disable interrupt */
1162 	psc_ops->cw_disable_ints(port);
1163 
1164 	/* Release interrupt */
1165 	free_irq(port->irq, port);
1166 }
1167 
1168 static void
1169 mpc52xx_uart_set_termios(struct uart_port *port, struct ktermios *new,
1170 			 struct ktermios *old)
1171 {
1172 	unsigned long flags;
1173 	unsigned char mr1, mr2;
1174 	unsigned int j;
1175 	unsigned int baud;
1176 
1177 	/* Prepare what we're gonna write */
1178 	mr1 = 0;
1179 
1180 	switch (new->c_cflag & CSIZE) {
1181 	case CS5:	mr1 |= MPC52xx_PSC_MODE_5_BITS;
1182 		break;
1183 	case CS6:	mr1 |= MPC52xx_PSC_MODE_6_BITS;
1184 		break;
1185 	case CS7:	mr1 |= MPC52xx_PSC_MODE_7_BITS;
1186 		break;
1187 	case CS8:
1188 	default:	mr1 |= MPC52xx_PSC_MODE_8_BITS;
1189 	}
1190 
1191 	if (new->c_cflag & PARENB) {
1192 		if (new->c_cflag & CMSPAR)
1193 			mr1 |= MPC52xx_PSC_MODE_PARFORCE;
1194 
1195 		/* With CMSPAR, PARODD also means high parity (same as termios) */
1196 		mr1 |= (new->c_cflag & PARODD) ?
1197 			MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
1198 	} else {
1199 		mr1 |= MPC52xx_PSC_MODE_PARNONE;
1200 	}
1201 
1202 	mr2 = 0;
1203 
1204 	if (new->c_cflag & CSTOPB)
1205 		mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
1206 	else
1207 		mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
1208 			MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
1209 			MPC52xx_PSC_MODE_ONE_STOP;
1210 
1211 	if (new->c_cflag & CRTSCTS) {
1212 		mr1 |= MPC52xx_PSC_MODE_RXRTS;
1213 		mr2 |= MPC52xx_PSC_MODE_TXCTS;
1214 	}
1215 
1216 	/* Get the lock */
1217 	spin_lock_irqsave(&port->lock, flags);
1218 
1219 	/* Do our best to flush TX & RX, so we don't lose anything */
1220 	/* But we don't wait indefinitely ! */
1221 	j = 5000000;	/* Maximum wait */
1222 	/* FIXME Can't receive chars since set_termios might be called at early
1223 	 * boot for the console, all stuff is not yet ready to receive at that
1224 	 * time and that just makes the kernel oops */
1225 	/* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
1226 	while (!mpc52xx_uart_tx_empty(port) && --j)
1227 		udelay(1);
1228 
1229 	if (!j)
1230 		printk(KERN_ERR "mpc52xx_uart.c: "
1231 			"Unable to flush RX & TX fifos in-time in set_termios."
1232 			"Some chars may have been lost.\n");
1233 
1234 	/* Reset the TX & RX */
1235 	psc_ops->command(port, MPC52xx_PSC_RST_RX);
1236 	psc_ops->command(port, MPC52xx_PSC_RST_TX);
1237 
1238 	/* Send new mode settings */
1239 	psc_ops->set_mode(port, mr1, mr2);
1240 	baud = psc_ops->set_baudrate(port, new, old);
1241 
1242 	/* Update the per-port timeout */
1243 	uart_update_timeout(port, new->c_cflag, baud);
1244 
1245 	if (UART_ENABLE_MS(port, new->c_cflag))
1246 		mpc52xx_uart_enable_ms(port);
1247 
1248 	/* Reenable TX & RX */
1249 	psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
1250 	psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
1251 
1252 	/* We're all set, release the lock */
1253 	spin_unlock_irqrestore(&port->lock, flags);
1254 }
1255 
1256 static const char *
1257 mpc52xx_uart_type(struct uart_port *port)
1258 {
1259 	/*
1260 	 * We keep using PORT_MPC52xx for historic reasons although it applies
1261 	 * for MPC512x, too, but print "MPC5xxx" to not irritate users
1262 	 */
1263 	return port->type == PORT_MPC52xx ? "MPC5xxx PSC" : NULL;
1264 }
1265 
1266 static void
1267 mpc52xx_uart_release_port(struct uart_port *port)
1268 {
1269 	if (psc_ops->clock_relse)
1270 		psc_ops->clock_relse(port);
1271 
1272 	/* remapped by us ? */
1273 	if (port->flags & UPF_IOREMAP) {
1274 		iounmap(port->membase);
1275 		port->membase = NULL;
1276 	}
1277 
1278 	release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
1279 }
1280 
1281 static int
1282 mpc52xx_uart_request_port(struct uart_port *port)
1283 {
1284 	int err;
1285 
1286 	if (port->flags & UPF_IOREMAP) /* Need to remap ? */
1287 		port->membase = ioremap(port->mapbase,
1288 					sizeof(struct mpc52xx_psc));
1289 
1290 	if (!port->membase)
1291 		return -EINVAL;
1292 
1293 	err = request_mem_region(port->mapbase, sizeof(struct mpc52xx_psc),
1294 			"mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
1295 
1296 	if (err)
1297 		goto out_membase;
1298 
1299 	if (psc_ops->clock_alloc) {
1300 		err = psc_ops->clock_alloc(port);
1301 		if (err)
1302 			goto out_mapregion;
1303 	}
1304 
1305 	return 0;
1306 
1307 out_mapregion:
1308 	release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
1309 out_membase:
1310 	if (port->flags & UPF_IOREMAP) {
1311 		iounmap(port->membase);
1312 		port->membase = NULL;
1313 	}
1314 	return err;
1315 }
1316 
1317 static void
1318 mpc52xx_uart_config_port(struct uart_port *port, int flags)
1319 {
1320 	if ((flags & UART_CONFIG_TYPE)
1321 		&& (mpc52xx_uart_request_port(port) == 0))
1322 		port->type = PORT_MPC52xx;
1323 }
1324 
1325 static int
1326 mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
1327 {
1328 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx)
1329 		return -EINVAL;
1330 
1331 	if ((ser->irq != port->irq) ||
1332 	    (ser->io_type != UPIO_MEM) ||
1333 	    (ser->baud_base != port->uartclk)  ||
1334 	    (ser->iomem_base != (void *)port->mapbase) ||
1335 	    (ser->hub6 != 0))
1336 		return -EINVAL;
1337 
1338 	return 0;
1339 }
1340 
1341 
1342 static struct uart_ops mpc52xx_uart_ops = {
1343 	.tx_empty	= mpc52xx_uart_tx_empty,
1344 	.set_mctrl	= mpc52xx_uart_set_mctrl,
1345 	.get_mctrl	= mpc52xx_uart_get_mctrl,
1346 	.stop_tx	= mpc52xx_uart_stop_tx,
1347 	.start_tx	= mpc52xx_uart_start_tx,
1348 	.stop_rx	= mpc52xx_uart_stop_rx,
1349 	.enable_ms	= mpc52xx_uart_enable_ms,
1350 	.break_ctl	= mpc52xx_uart_break_ctl,
1351 	.startup	= mpc52xx_uart_startup,
1352 	.shutdown	= mpc52xx_uart_shutdown,
1353 	.set_termios	= mpc52xx_uart_set_termios,
1354 /*	.pm		= mpc52xx_uart_pm,		Not supported yet */
1355 	.type		= mpc52xx_uart_type,
1356 	.release_port	= mpc52xx_uart_release_port,
1357 	.request_port	= mpc52xx_uart_request_port,
1358 	.config_port	= mpc52xx_uart_config_port,
1359 	.verify_port	= mpc52xx_uart_verify_port
1360 };
1361 
1362 
1363 /* ======================================================================== */
1364 /* Interrupt handling                                                       */
1365 /* ======================================================================== */
1366 
1367 static inline int
1368 mpc52xx_uart_int_rx_chars(struct uart_port *port)
1369 {
1370 	struct tty_port *tport = &port->state->port;
1371 	unsigned char ch, flag;
1372 	unsigned short status;
1373 
1374 	/* While we can read, do so ! */
1375 	while (psc_ops->raw_rx_rdy(port)) {
1376 		/* Get the char */
1377 		ch = psc_ops->read_char(port);
1378 
1379 		/* Handle sysreq char */
1380 #ifdef SUPPORT_SYSRQ
1381 		if (uart_handle_sysrq_char(port, ch)) {
1382 			port->sysrq = 0;
1383 			continue;
1384 		}
1385 #endif
1386 
1387 		/* Store it */
1388 
1389 		flag = TTY_NORMAL;
1390 		port->icount.rx++;
1391 
1392 		status = psc_ops->get_status(port);
1393 
1394 		if (status & (MPC52xx_PSC_SR_PE |
1395 			      MPC52xx_PSC_SR_FE |
1396 			      MPC52xx_PSC_SR_RB)) {
1397 
1398 			if (status & MPC52xx_PSC_SR_RB) {
1399 				flag = TTY_BREAK;
1400 				uart_handle_break(port);
1401 				port->icount.brk++;
1402 			} else if (status & MPC52xx_PSC_SR_PE) {
1403 				flag = TTY_PARITY;
1404 				port->icount.parity++;
1405 			}
1406 			else if (status & MPC52xx_PSC_SR_FE) {
1407 				flag = TTY_FRAME;
1408 				port->icount.frame++;
1409 			}
1410 
1411 			/* Clear error condition */
1412 			psc_ops->command(port, MPC52xx_PSC_RST_ERR_STAT);
1413 
1414 		}
1415 		tty_insert_flip_char(tport, ch, flag);
1416 		if (status & MPC52xx_PSC_SR_OE) {
1417 			/*
1418 			 * Overrun is special, since it's
1419 			 * reported immediately, and doesn't
1420 			 * affect the current character
1421 			 */
1422 			tty_insert_flip_char(tport, 0, TTY_OVERRUN);
1423 			port->icount.overrun++;
1424 		}
1425 	}
1426 
1427 	spin_unlock(&port->lock);
1428 	tty_flip_buffer_push(tport);
1429 	spin_lock(&port->lock);
1430 
1431 	return psc_ops->raw_rx_rdy(port);
1432 }
1433 
1434 static inline int
1435 mpc52xx_uart_int_tx_chars(struct uart_port *port)
1436 {
1437 	struct circ_buf *xmit = &port->state->xmit;
1438 
1439 	/* Process out of band chars */
1440 	if (port->x_char) {
1441 		psc_ops->write_char(port, port->x_char);
1442 		port->icount.tx++;
1443 		port->x_char = 0;
1444 		return 1;
1445 	}
1446 
1447 	/* Nothing to do ? */
1448 	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
1449 		mpc52xx_uart_stop_tx(port);
1450 		return 0;
1451 	}
1452 
1453 	/* Send chars */
1454 	while (psc_ops->raw_tx_rdy(port)) {
1455 		psc_ops->write_char(port, xmit->buf[xmit->tail]);
1456 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
1457 		port->icount.tx++;
1458 		if (uart_circ_empty(xmit))
1459 			break;
1460 	}
1461 
1462 	/* Wake up */
1463 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1464 		uart_write_wakeup(port);
1465 
1466 	/* Maybe we're done after all */
1467 	if (uart_circ_empty(xmit)) {
1468 		mpc52xx_uart_stop_tx(port);
1469 		return 0;
1470 	}
1471 
1472 	return 1;
1473 }
1474 
1475 static irqreturn_t
1476 mpc5xxx_uart_process_int(struct uart_port *port)
1477 {
1478 	unsigned long pass = ISR_PASS_LIMIT;
1479 	unsigned int keepgoing;
1480 	u8 status;
1481 
1482 	/* While we have stuff to do, we continue */
1483 	do {
1484 		/* If we don't find anything to do, we stop */
1485 		keepgoing = 0;
1486 
1487 		psc_ops->rx_clr_irq(port);
1488 		if (psc_ops->rx_rdy(port))
1489 			keepgoing |= mpc52xx_uart_int_rx_chars(port);
1490 
1491 		psc_ops->tx_clr_irq(port);
1492 		if (psc_ops->tx_rdy(port))
1493 			keepgoing |= mpc52xx_uart_int_tx_chars(port);
1494 
1495 		status = psc_ops->get_ipcr(port);
1496 		if (status & MPC52xx_PSC_D_DCD)
1497 			uart_handle_dcd_change(port, !(status & MPC52xx_PSC_DCD));
1498 
1499 		if (status & MPC52xx_PSC_D_CTS)
1500 			uart_handle_cts_change(port, !(status & MPC52xx_PSC_CTS));
1501 
1502 		/* Limit number of iteration */
1503 		if (!(--pass))
1504 			keepgoing = 0;
1505 
1506 	} while (keepgoing);
1507 
1508 	return IRQ_HANDLED;
1509 }
1510 
1511 static irqreturn_t
1512 mpc52xx_uart_int(int irq, void *dev_id)
1513 {
1514 	struct uart_port *port = dev_id;
1515 	irqreturn_t ret;
1516 
1517 	spin_lock(&port->lock);
1518 
1519 	ret = psc_ops->handle_irq(port);
1520 
1521 	spin_unlock(&port->lock);
1522 
1523 	return ret;
1524 }
1525 
1526 /* ======================================================================== */
1527 /* Console ( if applicable )                                                */
1528 /* ======================================================================== */
1529 
1530 #ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
1531 
1532 static void __init
1533 mpc52xx_console_get_options(struct uart_port *port,
1534 			    int *baud, int *parity, int *bits, int *flow)
1535 {
1536 	unsigned char mr1;
1537 
1538 	pr_debug("mpc52xx_console_get_options(port=%p)\n", port);
1539 
1540 	/* Read the mode registers */
1541 	mr1 = psc_ops->get_mr1(port);
1542 
1543 	/* CT{U,L}R are write-only ! */
1544 	*baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1545 
1546 	/* Parse them */
1547 	switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
1548 	case MPC52xx_PSC_MODE_5_BITS:
1549 		*bits = 5;
1550 		break;
1551 	case MPC52xx_PSC_MODE_6_BITS:
1552 		*bits = 6;
1553 		break;
1554 	case MPC52xx_PSC_MODE_7_BITS:
1555 		*bits = 7;
1556 		break;
1557 	case MPC52xx_PSC_MODE_8_BITS:
1558 	default:
1559 		*bits = 8;
1560 	}
1561 
1562 	if (mr1 & MPC52xx_PSC_MODE_PARNONE)
1563 		*parity = 'n';
1564 	else
1565 		*parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
1566 }
1567 
1568 static void
1569 mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
1570 {
1571 	struct uart_port *port = &mpc52xx_uart_ports[co->index];
1572 	unsigned int i, j;
1573 
1574 	/* Disable interrupts */
1575 	psc_ops->cw_disable_ints(port);
1576 
1577 	/* Wait the TX buffer to be empty */
1578 	j = 5000000;	/* Maximum wait */
1579 	while (!mpc52xx_uart_tx_empty(port) && --j)
1580 		udelay(1);
1581 
1582 	/* Write all the chars */
1583 	for (i = 0; i < count; i++, s++) {
1584 		/* Line return handling */
1585 		if (*s == '\n')
1586 			psc_ops->write_char(port, '\r');
1587 
1588 		/* Send the char */
1589 		psc_ops->write_char(port, *s);
1590 
1591 		/* Wait the TX buffer to be empty */
1592 		j = 20000;	/* Maximum wait */
1593 		while (!mpc52xx_uart_tx_empty(port) && --j)
1594 			udelay(1);
1595 	}
1596 
1597 	/* Restore interrupt state */
1598 	psc_ops->cw_restore_ints(port);
1599 }
1600 
1601 
1602 static int __init
1603 mpc52xx_console_setup(struct console *co, char *options)
1604 {
1605 	struct uart_port *port = &mpc52xx_uart_ports[co->index];
1606 	struct device_node *np = mpc52xx_uart_nodes[co->index];
1607 	unsigned int uartclk;
1608 	struct resource res;
1609 	int ret;
1610 
1611 	int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1612 	int bits = 8;
1613 	int parity = 'n';
1614 	int flow = 'n';
1615 
1616 	pr_debug("mpc52xx_console_setup co=%p, co->index=%i, options=%s\n",
1617 		 co, co->index, options);
1618 
1619 	if ((co->index < 0) || (co->index >= MPC52xx_PSC_MAXNUM)) {
1620 		pr_debug("PSC%x out of range\n", co->index);
1621 		return -EINVAL;
1622 	}
1623 
1624 	if (!np) {
1625 		pr_debug("PSC%x not found in device tree\n", co->index);
1626 		return -EINVAL;
1627 	}
1628 
1629 	pr_debug("Console on ttyPSC%x is %s\n",
1630 		 co->index, mpc52xx_uart_nodes[co->index]->full_name);
1631 
1632 	/* Fetch register locations */
1633 	ret = of_address_to_resource(np, 0, &res);
1634 	if (ret) {
1635 		pr_debug("Could not get resources for PSC%x\n", co->index);
1636 		return ret;
1637 	}
1638 
1639 	uartclk = mpc5xxx_get_bus_frequency(np);
1640 	if (uartclk == 0) {
1641 		pr_debug("Could not find uart clock frequency!\n");
1642 		return -EINVAL;
1643 	}
1644 
1645 	/* Basic port init. Needed since we use some uart_??? func before
1646 	 * real init for early access */
1647 	spin_lock_init(&port->lock);
1648 	port->uartclk = uartclk;
1649 	port->ops	= &mpc52xx_uart_ops;
1650 	port->mapbase = res.start;
1651 	port->membase = ioremap(res.start, sizeof(struct mpc52xx_psc));
1652 	port->irq = irq_of_parse_and_map(np, 0);
1653 
1654 	if (port->membase == NULL)
1655 		return -EINVAL;
1656 
1657 	pr_debug("mpc52xx-psc uart at %p, mapped to %p, irq=%x, freq=%i\n",
1658 		 (void *)port->mapbase, port->membase,
1659 		 port->irq, port->uartclk);
1660 
1661 	/* Setup the port parameters accoding to options */
1662 	if (options)
1663 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1664 	else
1665 		mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
1666 
1667 	pr_debug("Setting console parameters: %i %i%c1 flow=%c\n",
1668 		 baud, bits, parity, flow);
1669 
1670 	return uart_set_options(port, co, baud, parity, bits, flow);
1671 }
1672 
1673 
1674 static struct uart_driver mpc52xx_uart_driver;
1675 
1676 static struct console mpc52xx_console = {
1677 	.name	= "ttyPSC",
1678 	.write	= mpc52xx_console_write,
1679 	.device	= uart_console_device,
1680 	.setup	= mpc52xx_console_setup,
1681 	.flags	= CON_PRINTBUFFER,
1682 	.index	= -1,	/* Specified on the cmdline (e.g. console=ttyPSC0) */
1683 	.data	= &mpc52xx_uart_driver,
1684 };
1685 
1686 
1687 static int __init
1688 mpc52xx_console_init(void)
1689 {
1690 	mpc52xx_uart_of_enumerate();
1691 	register_console(&mpc52xx_console);
1692 	return 0;
1693 }
1694 
1695 console_initcall(mpc52xx_console_init);
1696 
1697 #define MPC52xx_PSC_CONSOLE &mpc52xx_console
1698 #else
1699 #define MPC52xx_PSC_CONSOLE NULL
1700 #endif
1701 
1702 
1703 /* ======================================================================== */
1704 /* UART Driver                                                              */
1705 /* ======================================================================== */
1706 
1707 static struct uart_driver mpc52xx_uart_driver = {
1708 	.driver_name	= "mpc52xx_psc_uart",
1709 	.dev_name	= "ttyPSC",
1710 	.major		= SERIAL_PSC_MAJOR,
1711 	.minor		= SERIAL_PSC_MINOR,
1712 	.nr		= MPC52xx_PSC_MAXNUM,
1713 	.cons		= MPC52xx_PSC_CONSOLE,
1714 };
1715 
1716 /* ======================================================================== */
1717 /* OF Platform Driver                                                       */
1718 /* ======================================================================== */
1719 
1720 static struct of_device_id mpc52xx_uart_of_match[] = {
1721 #ifdef CONFIG_PPC_MPC52xx
1722 	{ .compatible = "fsl,mpc5200b-psc-uart", .data = &mpc5200b_psc_ops, },
1723 	{ .compatible = "fsl,mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1724 	/* binding used by old lite5200 device trees: */
1725 	{ .compatible = "mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1726 	/* binding used by efika: */
1727 	{ .compatible = "mpc5200-serial", .data = &mpc52xx_psc_ops, },
1728 #endif
1729 #ifdef CONFIG_PPC_MPC512x
1730 	{ .compatible = "fsl,mpc5121-psc-uart", .data = &mpc512x_psc_ops, },
1731 	{ .compatible = "fsl,mpc5125-psc-uart", .data = &mpc5125_psc_ops, },
1732 #endif
1733 	{},
1734 };
1735 
1736 static int mpc52xx_uart_of_probe(struct platform_device *op)
1737 {
1738 	int idx = -1;
1739 	unsigned int uartclk;
1740 	struct uart_port *port = NULL;
1741 	struct resource res;
1742 	int ret;
1743 
1744 	/* Check validity & presence */
1745 	for (idx = 0; idx < MPC52xx_PSC_MAXNUM; idx++)
1746 		if (mpc52xx_uart_nodes[idx] == op->dev.of_node)
1747 			break;
1748 	if (idx >= MPC52xx_PSC_MAXNUM)
1749 		return -EINVAL;
1750 	pr_debug("Found %s assigned to ttyPSC%x\n",
1751 		 mpc52xx_uart_nodes[idx]->full_name, idx);
1752 
1753 	/* set the uart clock to the input clock of the psc, the different
1754 	 * prescalers are taken into account in the set_baudrate() methods
1755 	 * of the respective chip */
1756 	uartclk = mpc5xxx_get_bus_frequency(op->dev.of_node);
1757 	if (uartclk == 0) {
1758 		dev_dbg(&op->dev, "Could not find uart clock frequency!\n");
1759 		return -EINVAL;
1760 	}
1761 
1762 	/* Init the port structure */
1763 	port = &mpc52xx_uart_ports[idx];
1764 
1765 	spin_lock_init(&port->lock);
1766 	port->uartclk = uartclk;
1767 	port->fifosize	= 512;
1768 	port->iotype	= UPIO_MEM;
1769 	port->flags	= UPF_BOOT_AUTOCONF |
1770 			  (uart_console(port) ? 0 : UPF_IOREMAP);
1771 	port->line	= idx;
1772 	port->ops	= &mpc52xx_uart_ops;
1773 	port->dev	= &op->dev;
1774 
1775 	/* Search for IRQ and mapbase */
1776 	ret = of_address_to_resource(op->dev.of_node, 0, &res);
1777 	if (ret)
1778 		return ret;
1779 
1780 	port->mapbase = res.start;
1781 	if (!port->mapbase) {
1782 		dev_dbg(&op->dev, "Could not allocate resources for PSC\n");
1783 		return -EINVAL;
1784 	}
1785 
1786 	psc_ops->get_irq(port, op->dev.of_node);
1787 	if (port->irq == 0) {
1788 		dev_dbg(&op->dev, "Could not get irq\n");
1789 		return -EINVAL;
1790 	}
1791 
1792 	dev_dbg(&op->dev, "mpc52xx-psc uart at %p, irq=%x, freq=%i\n",
1793 		(void *)port->mapbase, port->irq, port->uartclk);
1794 
1795 	/* Add the port to the uart sub-system */
1796 	ret = uart_add_one_port(&mpc52xx_uart_driver, port);
1797 	if (ret)
1798 		return ret;
1799 
1800 	platform_set_drvdata(op, (void *)port);
1801 	return 0;
1802 }
1803 
1804 static int
1805 mpc52xx_uart_of_remove(struct platform_device *op)
1806 {
1807 	struct uart_port *port = platform_get_drvdata(op);
1808 
1809 	if (port)
1810 		uart_remove_one_port(&mpc52xx_uart_driver, port);
1811 
1812 	return 0;
1813 }
1814 
1815 #ifdef CONFIG_PM
1816 static int
1817 mpc52xx_uart_of_suspend(struct platform_device *op, pm_message_t state)
1818 {
1819 	struct uart_port *port = platform_get_drvdata(op);
1820 
1821 	if (port)
1822 		uart_suspend_port(&mpc52xx_uart_driver, port);
1823 
1824 	return 0;
1825 }
1826 
1827 static int
1828 mpc52xx_uart_of_resume(struct platform_device *op)
1829 {
1830 	struct uart_port *port = platform_get_drvdata(op);
1831 
1832 	if (port)
1833 		uart_resume_port(&mpc52xx_uart_driver, port);
1834 
1835 	return 0;
1836 }
1837 #endif
1838 
1839 static void
1840 mpc52xx_uart_of_assign(struct device_node *np)
1841 {
1842 	int i;
1843 
1844 	/* Find the first free PSC number */
1845 	for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1846 		if (mpc52xx_uart_nodes[i] == NULL) {
1847 			of_node_get(np);
1848 			mpc52xx_uart_nodes[i] = np;
1849 			return;
1850 		}
1851 	}
1852 }
1853 
1854 static void
1855 mpc52xx_uart_of_enumerate(void)
1856 {
1857 	static int enum_done;
1858 	struct device_node *np;
1859 	const struct  of_device_id *match;
1860 	int i;
1861 
1862 	if (enum_done)
1863 		return;
1864 
1865 	/* Assign index to each PSC in device tree */
1866 	for_each_matching_node(np, mpc52xx_uart_of_match) {
1867 		match = of_match_node(mpc52xx_uart_of_match, np);
1868 		psc_ops = match->data;
1869 		mpc52xx_uart_of_assign(np);
1870 	}
1871 
1872 	enum_done = 1;
1873 
1874 	for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1875 		if (mpc52xx_uart_nodes[i])
1876 			pr_debug("%s assigned to ttyPSC%x\n",
1877 				 mpc52xx_uart_nodes[i]->full_name, i);
1878 	}
1879 }
1880 
1881 MODULE_DEVICE_TABLE(of, mpc52xx_uart_of_match);
1882 
1883 static struct platform_driver mpc52xx_uart_of_driver = {
1884 	.probe		= mpc52xx_uart_of_probe,
1885 	.remove		= mpc52xx_uart_of_remove,
1886 #ifdef CONFIG_PM
1887 	.suspend	= mpc52xx_uart_of_suspend,
1888 	.resume		= mpc52xx_uart_of_resume,
1889 #endif
1890 	.driver = {
1891 		.name = "mpc52xx-psc-uart",
1892 		.owner = THIS_MODULE,
1893 		.of_match_table = mpc52xx_uart_of_match,
1894 	},
1895 };
1896 
1897 
1898 /* ======================================================================== */
1899 /* Module                                                                   */
1900 /* ======================================================================== */
1901 
1902 static int __init
1903 mpc52xx_uart_init(void)
1904 {
1905 	int ret;
1906 
1907 	printk(KERN_INFO "Serial: MPC52xx PSC UART driver\n");
1908 
1909 	ret = uart_register_driver(&mpc52xx_uart_driver);
1910 	if (ret) {
1911 		printk(KERN_ERR "%s: uart_register_driver failed (%i)\n",
1912 		       __FILE__, ret);
1913 		return ret;
1914 	}
1915 
1916 	mpc52xx_uart_of_enumerate();
1917 
1918 	/*
1919 	 * Map the PSC FIFO Controller and init if on MPC512x.
1920 	 */
1921 	if (psc_ops && psc_ops->fifoc_init) {
1922 		ret = psc_ops->fifoc_init();
1923 		if (ret)
1924 			goto err_init;
1925 	}
1926 
1927 	ret = platform_driver_register(&mpc52xx_uart_of_driver);
1928 	if (ret) {
1929 		printk(KERN_ERR "%s: platform_driver_register failed (%i)\n",
1930 		       __FILE__, ret);
1931 		goto err_reg;
1932 	}
1933 
1934 	return 0;
1935 err_reg:
1936 	if (psc_ops && psc_ops->fifoc_uninit)
1937 		psc_ops->fifoc_uninit();
1938 err_init:
1939 	uart_unregister_driver(&mpc52xx_uart_driver);
1940 	return ret;
1941 }
1942 
1943 static void __exit
1944 mpc52xx_uart_exit(void)
1945 {
1946 	if (psc_ops->fifoc_uninit)
1947 		psc_ops->fifoc_uninit();
1948 
1949 	platform_driver_unregister(&mpc52xx_uart_of_driver);
1950 	uart_unregister_driver(&mpc52xx_uart_driver);
1951 }
1952 
1953 
1954 module_init(mpc52xx_uart_init);
1955 module_exit(mpc52xx_uart_exit);
1956 
1957 MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
1958 MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
1959 MODULE_LICENSE("GPL");
1960