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_send_xchar(struct uart_port *port, char ch)
1091 {
1092 	unsigned long flags;
1093 	spin_lock_irqsave(&port->lock, flags);
1094 
1095 	port->x_char = ch;
1096 	if (ch) {
1097 		/* Make sure tx interrupts are on */
1098 		/* Truly necessary ??? They should be anyway */
1099 		psc_ops->start_tx(port);
1100 	}
1101 
1102 	spin_unlock_irqrestore(&port->lock, flags);
1103 }
1104 
1105 static void
1106 mpc52xx_uart_stop_rx(struct uart_port *port)
1107 {
1108 	/* port->lock taken by caller */
1109 	psc_ops->stop_rx(port);
1110 }
1111 
1112 static void
1113 mpc52xx_uart_enable_ms(struct uart_port *port)
1114 {
1115 	psc_ops->enable_ms(port);
1116 }
1117 
1118 static void
1119 mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
1120 {
1121 	unsigned long flags;
1122 	spin_lock_irqsave(&port->lock, flags);
1123 
1124 	if (ctl == -1)
1125 		psc_ops->command(port, MPC52xx_PSC_START_BRK);
1126 	else
1127 		psc_ops->command(port, MPC52xx_PSC_STOP_BRK);
1128 
1129 	spin_unlock_irqrestore(&port->lock, flags);
1130 }
1131 
1132 static int
1133 mpc52xx_uart_startup(struct uart_port *port)
1134 {
1135 	int ret;
1136 
1137 	if (psc_ops->clock) {
1138 		ret = psc_ops->clock(port, 1);
1139 		if (ret)
1140 			return ret;
1141 	}
1142 
1143 	/* Request IRQ */
1144 	ret = request_irq(port->irq, mpc52xx_uart_int,
1145 			  port->irqflags, "mpc52xx_psc_uart", port);
1146 	if (ret)
1147 		return ret;
1148 
1149 	/* Reset/activate the port, clear and enable interrupts */
1150 	psc_ops->command(port, MPC52xx_PSC_RST_RX);
1151 	psc_ops->command(port, MPC52xx_PSC_RST_TX);
1152 
1153 	psc_ops->set_sicr(port, 0);	/* UART mode DCD ignored */
1154 
1155 	psc_ops->fifo_init(port);
1156 
1157 	psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
1158 	psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
1159 
1160 	return 0;
1161 }
1162 
1163 static void
1164 mpc52xx_uart_shutdown(struct uart_port *port)
1165 {
1166 	/* Shut down the port.  Leave TX active if on a console port */
1167 	psc_ops->command(port, MPC52xx_PSC_RST_RX);
1168 	if (!uart_console(port))
1169 		psc_ops->command(port, MPC52xx_PSC_RST_TX);
1170 
1171 	port->read_status_mask = 0;
1172 	psc_ops->set_imr(port, port->read_status_mask);
1173 
1174 	if (psc_ops->clock)
1175 		psc_ops->clock(port, 0);
1176 
1177 	/* Disable interrupt */
1178 	psc_ops->cw_disable_ints(port);
1179 
1180 	/* Release interrupt */
1181 	free_irq(port->irq, port);
1182 }
1183 
1184 static void
1185 mpc52xx_uart_set_termios(struct uart_port *port, struct ktermios *new,
1186 			 struct ktermios *old)
1187 {
1188 	unsigned long flags;
1189 	unsigned char mr1, mr2;
1190 	unsigned int j;
1191 	unsigned int baud;
1192 
1193 	/* Prepare what we're gonna write */
1194 	mr1 = 0;
1195 
1196 	switch (new->c_cflag & CSIZE) {
1197 	case CS5:	mr1 |= MPC52xx_PSC_MODE_5_BITS;
1198 		break;
1199 	case CS6:	mr1 |= MPC52xx_PSC_MODE_6_BITS;
1200 		break;
1201 	case CS7:	mr1 |= MPC52xx_PSC_MODE_7_BITS;
1202 		break;
1203 	case CS8:
1204 	default:	mr1 |= MPC52xx_PSC_MODE_8_BITS;
1205 	}
1206 
1207 	if (new->c_cflag & PARENB) {
1208 		if (new->c_cflag & CMSPAR)
1209 			mr1 |= MPC52xx_PSC_MODE_PARFORCE;
1210 
1211 		/* With CMSPAR, PARODD also means high parity (same as termios) */
1212 		mr1 |= (new->c_cflag & PARODD) ?
1213 			MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
1214 	} else {
1215 		mr1 |= MPC52xx_PSC_MODE_PARNONE;
1216 	}
1217 
1218 	mr2 = 0;
1219 
1220 	if (new->c_cflag & CSTOPB)
1221 		mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
1222 	else
1223 		mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
1224 			MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
1225 			MPC52xx_PSC_MODE_ONE_STOP;
1226 
1227 	if (new->c_cflag & CRTSCTS) {
1228 		mr1 |= MPC52xx_PSC_MODE_RXRTS;
1229 		mr2 |= MPC52xx_PSC_MODE_TXCTS;
1230 	}
1231 
1232 	/* Get the lock */
1233 	spin_lock_irqsave(&port->lock, flags);
1234 
1235 	/* Do our best to flush TX & RX, so we don't lose anything */
1236 	/* But we don't wait indefinitely ! */
1237 	j = 5000000;	/* Maximum wait */
1238 	/* FIXME Can't receive chars since set_termios might be called at early
1239 	 * boot for the console, all stuff is not yet ready to receive at that
1240 	 * time and that just makes the kernel oops */
1241 	/* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
1242 	while (!mpc52xx_uart_tx_empty(port) && --j)
1243 		udelay(1);
1244 
1245 	if (!j)
1246 		printk(KERN_ERR "mpc52xx_uart.c: "
1247 			"Unable to flush RX & TX fifos in-time in set_termios."
1248 			"Some chars may have been lost.\n");
1249 
1250 	/* Reset the TX & RX */
1251 	psc_ops->command(port, MPC52xx_PSC_RST_RX);
1252 	psc_ops->command(port, MPC52xx_PSC_RST_TX);
1253 
1254 	/* Send new mode settings */
1255 	psc_ops->set_mode(port, mr1, mr2);
1256 	baud = psc_ops->set_baudrate(port, new, old);
1257 
1258 	/* Update the per-port timeout */
1259 	uart_update_timeout(port, new->c_cflag, baud);
1260 
1261 	if (UART_ENABLE_MS(port, new->c_cflag))
1262 		mpc52xx_uart_enable_ms(port);
1263 
1264 	/* Reenable TX & RX */
1265 	psc_ops->command(port, MPC52xx_PSC_TX_ENABLE);
1266 	psc_ops->command(port, MPC52xx_PSC_RX_ENABLE);
1267 
1268 	/* We're all set, release the lock */
1269 	spin_unlock_irqrestore(&port->lock, flags);
1270 }
1271 
1272 static const char *
1273 mpc52xx_uart_type(struct uart_port *port)
1274 {
1275 	/*
1276 	 * We keep using PORT_MPC52xx for historic reasons although it applies
1277 	 * for MPC512x, too, but print "MPC5xxx" to not irritate users
1278 	 */
1279 	return port->type == PORT_MPC52xx ? "MPC5xxx PSC" : NULL;
1280 }
1281 
1282 static void
1283 mpc52xx_uart_release_port(struct uart_port *port)
1284 {
1285 	if (psc_ops->clock_relse)
1286 		psc_ops->clock_relse(port);
1287 
1288 	/* remapped by us ? */
1289 	if (port->flags & UPF_IOREMAP) {
1290 		iounmap(port->membase);
1291 		port->membase = NULL;
1292 	}
1293 
1294 	release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
1295 }
1296 
1297 static int
1298 mpc52xx_uart_request_port(struct uart_port *port)
1299 {
1300 	int err;
1301 
1302 	if (port->flags & UPF_IOREMAP) /* Need to remap ? */
1303 		port->membase = ioremap(port->mapbase,
1304 					sizeof(struct mpc52xx_psc));
1305 
1306 	if (!port->membase)
1307 		return -EINVAL;
1308 
1309 	err = request_mem_region(port->mapbase, sizeof(struct mpc52xx_psc),
1310 			"mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
1311 
1312 	if (err)
1313 		goto out_membase;
1314 
1315 	if (psc_ops->clock_alloc) {
1316 		err = psc_ops->clock_alloc(port);
1317 		if (err)
1318 			goto out_mapregion;
1319 	}
1320 
1321 	return 0;
1322 
1323 out_mapregion:
1324 	release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
1325 out_membase:
1326 	if (port->flags & UPF_IOREMAP) {
1327 		iounmap(port->membase);
1328 		port->membase = NULL;
1329 	}
1330 	return err;
1331 }
1332 
1333 static void
1334 mpc52xx_uart_config_port(struct uart_port *port, int flags)
1335 {
1336 	if ((flags & UART_CONFIG_TYPE)
1337 		&& (mpc52xx_uart_request_port(port) == 0))
1338 		port->type = PORT_MPC52xx;
1339 }
1340 
1341 static int
1342 mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
1343 {
1344 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx)
1345 		return -EINVAL;
1346 
1347 	if ((ser->irq != port->irq) ||
1348 	    (ser->io_type != UPIO_MEM) ||
1349 	    (ser->baud_base != port->uartclk)  ||
1350 	    (ser->iomem_base != (void *)port->mapbase) ||
1351 	    (ser->hub6 != 0))
1352 		return -EINVAL;
1353 
1354 	return 0;
1355 }
1356 
1357 
1358 static struct uart_ops mpc52xx_uart_ops = {
1359 	.tx_empty	= mpc52xx_uart_tx_empty,
1360 	.set_mctrl	= mpc52xx_uart_set_mctrl,
1361 	.get_mctrl	= mpc52xx_uart_get_mctrl,
1362 	.stop_tx	= mpc52xx_uart_stop_tx,
1363 	.start_tx	= mpc52xx_uart_start_tx,
1364 	.send_xchar	= mpc52xx_uart_send_xchar,
1365 	.stop_rx	= mpc52xx_uart_stop_rx,
1366 	.enable_ms	= mpc52xx_uart_enable_ms,
1367 	.break_ctl	= mpc52xx_uart_break_ctl,
1368 	.startup	= mpc52xx_uart_startup,
1369 	.shutdown	= mpc52xx_uart_shutdown,
1370 	.set_termios	= mpc52xx_uart_set_termios,
1371 /*	.pm		= mpc52xx_uart_pm,		Not supported yet */
1372 	.type		= mpc52xx_uart_type,
1373 	.release_port	= mpc52xx_uart_release_port,
1374 	.request_port	= mpc52xx_uart_request_port,
1375 	.config_port	= mpc52xx_uart_config_port,
1376 	.verify_port	= mpc52xx_uart_verify_port
1377 };
1378 
1379 
1380 /* ======================================================================== */
1381 /* Interrupt handling                                                       */
1382 /* ======================================================================== */
1383 
1384 static inline int
1385 mpc52xx_uart_int_rx_chars(struct uart_port *port)
1386 {
1387 	struct tty_port *tport = &port->state->port;
1388 	unsigned char ch, flag;
1389 	unsigned short status;
1390 
1391 	/* While we can read, do so ! */
1392 	while (psc_ops->raw_rx_rdy(port)) {
1393 		/* Get the char */
1394 		ch = psc_ops->read_char(port);
1395 
1396 		/* Handle sysreq char */
1397 #ifdef SUPPORT_SYSRQ
1398 		if (uart_handle_sysrq_char(port, ch)) {
1399 			port->sysrq = 0;
1400 			continue;
1401 		}
1402 #endif
1403 
1404 		/* Store it */
1405 
1406 		flag = TTY_NORMAL;
1407 		port->icount.rx++;
1408 
1409 		status = psc_ops->get_status(port);
1410 
1411 		if (status & (MPC52xx_PSC_SR_PE |
1412 			      MPC52xx_PSC_SR_FE |
1413 			      MPC52xx_PSC_SR_RB)) {
1414 
1415 			if (status & MPC52xx_PSC_SR_RB) {
1416 				flag = TTY_BREAK;
1417 				uart_handle_break(port);
1418 				port->icount.brk++;
1419 			} else if (status & MPC52xx_PSC_SR_PE) {
1420 				flag = TTY_PARITY;
1421 				port->icount.parity++;
1422 			}
1423 			else if (status & MPC52xx_PSC_SR_FE) {
1424 				flag = TTY_FRAME;
1425 				port->icount.frame++;
1426 			}
1427 
1428 			/* Clear error condition */
1429 			psc_ops->command(port, MPC52xx_PSC_RST_ERR_STAT);
1430 
1431 		}
1432 		tty_insert_flip_char(tport, ch, flag);
1433 		if (status & MPC52xx_PSC_SR_OE) {
1434 			/*
1435 			 * Overrun is special, since it's
1436 			 * reported immediately, and doesn't
1437 			 * affect the current character
1438 			 */
1439 			tty_insert_flip_char(tport, 0, TTY_OVERRUN);
1440 			port->icount.overrun++;
1441 		}
1442 	}
1443 
1444 	spin_unlock(&port->lock);
1445 	tty_flip_buffer_push(tport);
1446 	spin_lock(&port->lock);
1447 
1448 	return psc_ops->raw_rx_rdy(port);
1449 }
1450 
1451 static inline int
1452 mpc52xx_uart_int_tx_chars(struct uart_port *port)
1453 {
1454 	struct circ_buf *xmit = &port->state->xmit;
1455 
1456 	/* Process out of band chars */
1457 	if (port->x_char) {
1458 		psc_ops->write_char(port, port->x_char);
1459 		port->icount.tx++;
1460 		port->x_char = 0;
1461 		return 1;
1462 	}
1463 
1464 	/* Nothing to do ? */
1465 	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
1466 		mpc52xx_uart_stop_tx(port);
1467 		return 0;
1468 	}
1469 
1470 	/* Send chars */
1471 	while (psc_ops->raw_tx_rdy(port)) {
1472 		psc_ops->write_char(port, xmit->buf[xmit->tail]);
1473 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
1474 		port->icount.tx++;
1475 		if (uart_circ_empty(xmit))
1476 			break;
1477 	}
1478 
1479 	/* Wake up */
1480 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1481 		uart_write_wakeup(port);
1482 
1483 	/* Maybe we're done after all */
1484 	if (uart_circ_empty(xmit)) {
1485 		mpc52xx_uart_stop_tx(port);
1486 		return 0;
1487 	}
1488 
1489 	return 1;
1490 }
1491 
1492 static irqreturn_t
1493 mpc5xxx_uart_process_int(struct uart_port *port)
1494 {
1495 	unsigned long pass = ISR_PASS_LIMIT;
1496 	unsigned int keepgoing;
1497 	u8 status;
1498 
1499 	/* While we have stuff to do, we continue */
1500 	do {
1501 		/* If we don't find anything to do, we stop */
1502 		keepgoing = 0;
1503 
1504 		psc_ops->rx_clr_irq(port);
1505 		if (psc_ops->rx_rdy(port))
1506 			keepgoing |= mpc52xx_uart_int_rx_chars(port);
1507 
1508 		psc_ops->tx_clr_irq(port);
1509 		if (psc_ops->tx_rdy(port))
1510 			keepgoing |= mpc52xx_uart_int_tx_chars(port);
1511 
1512 		status = psc_ops->get_ipcr(port);
1513 		if (status & MPC52xx_PSC_D_DCD)
1514 			uart_handle_dcd_change(port, !(status & MPC52xx_PSC_DCD));
1515 
1516 		if (status & MPC52xx_PSC_D_CTS)
1517 			uart_handle_cts_change(port, !(status & MPC52xx_PSC_CTS));
1518 
1519 		/* Limit number of iteration */
1520 		if (!(--pass))
1521 			keepgoing = 0;
1522 
1523 	} while (keepgoing);
1524 
1525 	return IRQ_HANDLED;
1526 }
1527 
1528 static irqreturn_t
1529 mpc52xx_uart_int(int irq, void *dev_id)
1530 {
1531 	struct uart_port *port = dev_id;
1532 	irqreturn_t ret;
1533 
1534 	spin_lock(&port->lock);
1535 
1536 	ret = psc_ops->handle_irq(port);
1537 
1538 	spin_unlock(&port->lock);
1539 
1540 	return ret;
1541 }
1542 
1543 /* ======================================================================== */
1544 /* Console ( if applicable )                                                */
1545 /* ======================================================================== */
1546 
1547 #ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
1548 
1549 static void __init
1550 mpc52xx_console_get_options(struct uart_port *port,
1551 			    int *baud, int *parity, int *bits, int *flow)
1552 {
1553 	unsigned char mr1;
1554 
1555 	pr_debug("mpc52xx_console_get_options(port=%p)\n", port);
1556 
1557 	/* Read the mode registers */
1558 	mr1 = psc_ops->get_mr1(port);
1559 
1560 	/* CT{U,L}R are write-only ! */
1561 	*baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1562 
1563 	/* Parse them */
1564 	switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
1565 	case MPC52xx_PSC_MODE_5_BITS:
1566 		*bits = 5;
1567 		break;
1568 	case MPC52xx_PSC_MODE_6_BITS:
1569 		*bits = 6;
1570 		break;
1571 	case MPC52xx_PSC_MODE_7_BITS:
1572 		*bits = 7;
1573 		break;
1574 	case MPC52xx_PSC_MODE_8_BITS:
1575 	default:
1576 		*bits = 8;
1577 	}
1578 
1579 	if (mr1 & MPC52xx_PSC_MODE_PARNONE)
1580 		*parity = 'n';
1581 	else
1582 		*parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
1583 }
1584 
1585 static void
1586 mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
1587 {
1588 	struct uart_port *port = &mpc52xx_uart_ports[co->index];
1589 	unsigned int i, j;
1590 
1591 	/* Disable interrupts */
1592 	psc_ops->cw_disable_ints(port);
1593 
1594 	/* Wait the TX buffer to be empty */
1595 	j = 5000000;	/* Maximum wait */
1596 	while (!mpc52xx_uart_tx_empty(port) && --j)
1597 		udelay(1);
1598 
1599 	/* Write all the chars */
1600 	for (i = 0; i < count; i++, s++) {
1601 		/* Line return handling */
1602 		if (*s == '\n')
1603 			psc_ops->write_char(port, '\r');
1604 
1605 		/* Send the char */
1606 		psc_ops->write_char(port, *s);
1607 
1608 		/* Wait the TX buffer to be empty */
1609 		j = 20000;	/* Maximum wait */
1610 		while (!mpc52xx_uart_tx_empty(port) && --j)
1611 			udelay(1);
1612 	}
1613 
1614 	/* Restore interrupt state */
1615 	psc_ops->cw_restore_ints(port);
1616 }
1617 
1618 
1619 static int __init
1620 mpc52xx_console_setup(struct console *co, char *options)
1621 {
1622 	struct uart_port *port = &mpc52xx_uart_ports[co->index];
1623 	struct device_node *np = mpc52xx_uart_nodes[co->index];
1624 	unsigned int uartclk;
1625 	struct resource res;
1626 	int ret;
1627 
1628 	int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
1629 	int bits = 8;
1630 	int parity = 'n';
1631 	int flow = 'n';
1632 
1633 	pr_debug("mpc52xx_console_setup co=%p, co->index=%i, options=%s\n",
1634 		 co, co->index, options);
1635 
1636 	if ((co->index < 0) || (co->index >= MPC52xx_PSC_MAXNUM)) {
1637 		pr_debug("PSC%x out of range\n", co->index);
1638 		return -EINVAL;
1639 	}
1640 
1641 	if (!np) {
1642 		pr_debug("PSC%x not found in device tree\n", co->index);
1643 		return -EINVAL;
1644 	}
1645 
1646 	pr_debug("Console on ttyPSC%x is %s\n",
1647 		 co->index, mpc52xx_uart_nodes[co->index]->full_name);
1648 
1649 	/* Fetch register locations */
1650 	ret = of_address_to_resource(np, 0, &res);
1651 	if (ret) {
1652 		pr_debug("Could not get resources for PSC%x\n", co->index);
1653 		return ret;
1654 	}
1655 
1656 	uartclk = mpc5xxx_get_bus_frequency(np);
1657 	if (uartclk == 0) {
1658 		pr_debug("Could not find uart clock frequency!\n");
1659 		return -EINVAL;
1660 	}
1661 
1662 	/* Basic port init. Needed since we use some uart_??? func before
1663 	 * real init for early access */
1664 	spin_lock_init(&port->lock);
1665 	port->uartclk = uartclk;
1666 	port->ops	= &mpc52xx_uart_ops;
1667 	port->mapbase = res.start;
1668 	port->membase = ioremap(res.start, sizeof(struct mpc52xx_psc));
1669 	port->irq = irq_of_parse_and_map(np, 0);
1670 
1671 	if (port->membase == NULL)
1672 		return -EINVAL;
1673 
1674 	pr_debug("mpc52xx-psc uart at %p, mapped to %p, irq=%x, freq=%i\n",
1675 		 (void *)port->mapbase, port->membase,
1676 		 port->irq, port->uartclk);
1677 
1678 	/* Setup the port parameters accoding to options */
1679 	if (options)
1680 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1681 	else
1682 		mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
1683 
1684 	pr_debug("Setting console parameters: %i %i%c1 flow=%c\n",
1685 		 baud, bits, parity, flow);
1686 
1687 	return uart_set_options(port, co, baud, parity, bits, flow);
1688 }
1689 
1690 
1691 static struct uart_driver mpc52xx_uart_driver;
1692 
1693 static struct console mpc52xx_console = {
1694 	.name	= "ttyPSC",
1695 	.write	= mpc52xx_console_write,
1696 	.device	= uart_console_device,
1697 	.setup	= mpc52xx_console_setup,
1698 	.flags	= CON_PRINTBUFFER,
1699 	.index	= -1,	/* Specified on the cmdline (e.g. console=ttyPSC0) */
1700 	.data	= &mpc52xx_uart_driver,
1701 };
1702 
1703 
1704 static int __init
1705 mpc52xx_console_init(void)
1706 {
1707 	mpc52xx_uart_of_enumerate();
1708 	register_console(&mpc52xx_console);
1709 	return 0;
1710 }
1711 
1712 console_initcall(mpc52xx_console_init);
1713 
1714 #define MPC52xx_PSC_CONSOLE &mpc52xx_console
1715 #else
1716 #define MPC52xx_PSC_CONSOLE NULL
1717 #endif
1718 
1719 
1720 /* ======================================================================== */
1721 /* UART Driver                                                              */
1722 /* ======================================================================== */
1723 
1724 static struct uart_driver mpc52xx_uart_driver = {
1725 	.driver_name	= "mpc52xx_psc_uart",
1726 	.dev_name	= "ttyPSC",
1727 	.major		= SERIAL_PSC_MAJOR,
1728 	.minor		= SERIAL_PSC_MINOR,
1729 	.nr		= MPC52xx_PSC_MAXNUM,
1730 	.cons		= MPC52xx_PSC_CONSOLE,
1731 };
1732 
1733 /* ======================================================================== */
1734 /* OF Platform Driver                                                       */
1735 /* ======================================================================== */
1736 
1737 static struct of_device_id mpc52xx_uart_of_match[] = {
1738 #ifdef CONFIG_PPC_MPC52xx
1739 	{ .compatible = "fsl,mpc5200b-psc-uart", .data = &mpc5200b_psc_ops, },
1740 	{ .compatible = "fsl,mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1741 	/* binding used by old lite5200 device trees: */
1742 	{ .compatible = "mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
1743 	/* binding used by efika: */
1744 	{ .compatible = "mpc5200-serial", .data = &mpc52xx_psc_ops, },
1745 #endif
1746 #ifdef CONFIG_PPC_MPC512x
1747 	{ .compatible = "fsl,mpc5121-psc-uart", .data = &mpc512x_psc_ops, },
1748 	{ .compatible = "fsl,mpc5125-psc-uart", .data = &mpc5125_psc_ops, },
1749 #endif
1750 	{},
1751 };
1752 
1753 static int mpc52xx_uart_of_probe(struct platform_device *op)
1754 {
1755 	int idx = -1;
1756 	unsigned int uartclk;
1757 	struct uart_port *port = NULL;
1758 	struct resource res;
1759 	int ret;
1760 
1761 	/* Check validity & presence */
1762 	for (idx = 0; idx < MPC52xx_PSC_MAXNUM; idx++)
1763 		if (mpc52xx_uart_nodes[idx] == op->dev.of_node)
1764 			break;
1765 	if (idx >= MPC52xx_PSC_MAXNUM)
1766 		return -EINVAL;
1767 	pr_debug("Found %s assigned to ttyPSC%x\n",
1768 		 mpc52xx_uart_nodes[idx]->full_name, idx);
1769 
1770 	/* set the uart clock to the input clock of the psc, the different
1771 	 * prescalers are taken into account in the set_baudrate() methods
1772 	 * of the respective chip */
1773 	uartclk = mpc5xxx_get_bus_frequency(op->dev.of_node);
1774 	if (uartclk == 0) {
1775 		dev_dbg(&op->dev, "Could not find uart clock frequency!\n");
1776 		return -EINVAL;
1777 	}
1778 
1779 	/* Init the port structure */
1780 	port = &mpc52xx_uart_ports[idx];
1781 
1782 	spin_lock_init(&port->lock);
1783 	port->uartclk = uartclk;
1784 	port->fifosize	= 512;
1785 	port->iotype	= UPIO_MEM;
1786 	port->flags	= UPF_BOOT_AUTOCONF |
1787 			  (uart_console(port) ? 0 : UPF_IOREMAP);
1788 	port->line	= idx;
1789 	port->ops	= &mpc52xx_uart_ops;
1790 	port->dev	= &op->dev;
1791 
1792 	/* Search for IRQ and mapbase */
1793 	ret = of_address_to_resource(op->dev.of_node, 0, &res);
1794 	if (ret)
1795 		return ret;
1796 
1797 	port->mapbase = res.start;
1798 	if (!port->mapbase) {
1799 		dev_dbg(&op->dev, "Could not allocate resources for PSC\n");
1800 		return -EINVAL;
1801 	}
1802 
1803 	psc_ops->get_irq(port, op->dev.of_node);
1804 	if (port->irq == 0) {
1805 		dev_dbg(&op->dev, "Could not get irq\n");
1806 		return -EINVAL;
1807 	}
1808 
1809 	dev_dbg(&op->dev, "mpc52xx-psc uart at %p, irq=%x, freq=%i\n",
1810 		(void *)port->mapbase, port->irq, port->uartclk);
1811 
1812 	/* Add the port to the uart sub-system */
1813 	ret = uart_add_one_port(&mpc52xx_uart_driver, port);
1814 	if (ret)
1815 		return ret;
1816 
1817 	platform_set_drvdata(op, (void *)port);
1818 	return 0;
1819 }
1820 
1821 static int
1822 mpc52xx_uart_of_remove(struct platform_device *op)
1823 {
1824 	struct uart_port *port = platform_get_drvdata(op);
1825 
1826 	if (port)
1827 		uart_remove_one_port(&mpc52xx_uart_driver, port);
1828 
1829 	return 0;
1830 }
1831 
1832 #ifdef CONFIG_PM
1833 static int
1834 mpc52xx_uart_of_suspend(struct platform_device *op, pm_message_t state)
1835 {
1836 	struct uart_port *port = platform_get_drvdata(op);
1837 
1838 	if (port)
1839 		uart_suspend_port(&mpc52xx_uart_driver, port);
1840 
1841 	return 0;
1842 }
1843 
1844 static int
1845 mpc52xx_uart_of_resume(struct platform_device *op)
1846 {
1847 	struct uart_port *port = platform_get_drvdata(op);
1848 
1849 	if (port)
1850 		uart_resume_port(&mpc52xx_uart_driver, port);
1851 
1852 	return 0;
1853 }
1854 #endif
1855 
1856 static void
1857 mpc52xx_uart_of_assign(struct device_node *np)
1858 {
1859 	int i;
1860 
1861 	/* Find the first free PSC number */
1862 	for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1863 		if (mpc52xx_uart_nodes[i] == NULL) {
1864 			of_node_get(np);
1865 			mpc52xx_uart_nodes[i] = np;
1866 			return;
1867 		}
1868 	}
1869 }
1870 
1871 static void
1872 mpc52xx_uart_of_enumerate(void)
1873 {
1874 	static int enum_done;
1875 	struct device_node *np;
1876 	const struct  of_device_id *match;
1877 	int i;
1878 
1879 	if (enum_done)
1880 		return;
1881 
1882 	/* Assign index to each PSC in device tree */
1883 	for_each_matching_node(np, mpc52xx_uart_of_match) {
1884 		match = of_match_node(mpc52xx_uart_of_match, np);
1885 		psc_ops = match->data;
1886 		mpc52xx_uart_of_assign(np);
1887 	}
1888 
1889 	enum_done = 1;
1890 
1891 	for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
1892 		if (mpc52xx_uart_nodes[i])
1893 			pr_debug("%s assigned to ttyPSC%x\n",
1894 				 mpc52xx_uart_nodes[i]->full_name, i);
1895 	}
1896 }
1897 
1898 MODULE_DEVICE_TABLE(of, mpc52xx_uart_of_match);
1899 
1900 static struct platform_driver mpc52xx_uart_of_driver = {
1901 	.probe		= mpc52xx_uart_of_probe,
1902 	.remove		= mpc52xx_uart_of_remove,
1903 #ifdef CONFIG_PM
1904 	.suspend	= mpc52xx_uart_of_suspend,
1905 	.resume		= mpc52xx_uart_of_resume,
1906 #endif
1907 	.driver = {
1908 		.name = "mpc52xx-psc-uart",
1909 		.owner = THIS_MODULE,
1910 		.of_match_table = mpc52xx_uart_of_match,
1911 	},
1912 };
1913 
1914 
1915 /* ======================================================================== */
1916 /* Module                                                                   */
1917 /* ======================================================================== */
1918 
1919 static int __init
1920 mpc52xx_uart_init(void)
1921 {
1922 	int ret;
1923 
1924 	printk(KERN_INFO "Serial: MPC52xx PSC UART driver\n");
1925 
1926 	ret = uart_register_driver(&mpc52xx_uart_driver);
1927 	if (ret) {
1928 		printk(KERN_ERR "%s: uart_register_driver failed (%i)\n",
1929 		       __FILE__, ret);
1930 		return ret;
1931 	}
1932 
1933 	mpc52xx_uart_of_enumerate();
1934 
1935 	/*
1936 	 * Map the PSC FIFO Controller and init if on MPC512x.
1937 	 */
1938 	if (psc_ops && psc_ops->fifoc_init) {
1939 		ret = psc_ops->fifoc_init();
1940 		if (ret)
1941 			goto err_init;
1942 	}
1943 
1944 	ret = platform_driver_register(&mpc52xx_uart_of_driver);
1945 	if (ret) {
1946 		printk(KERN_ERR "%s: platform_driver_register failed (%i)\n",
1947 		       __FILE__, ret);
1948 		goto err_reg;
1949 	}
1950 
1951 	return 0;
1952 err_reg:
1953 	if (psc_ops && psc_ops->fifoc_uninit)
1954 		psc_ops->fifoc_uninit();
1955 err_init:
1956 	uart_unregister_driver(&mpc52xx_uart_driver);
1957 	return ret;
1958 }
1959 
1960 static void __exit
1961 mpc52xx_uart_exit(void)
1962 {
1963 	if (psc_ops->fifoc_uninit)
1964 		psc_ops->fifoc_uninit();
1965 
1966 	platform_driver_unregister(&mpc52xx_uart_of_driver);
1967 	uart_unregister_driver(&mpc52xx_uart_driver);
1968 }
1969 
1970 
1971 module_init(mpc52xx_uart_init);
1972 module_exit(mpc52xx_uart_exit);
1973 
1974 MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
1975 MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
1976 MODULE_LICENSE("GPL");
1977