1/*
2 * Freescale QUICC Engine UART device driver
3 *
4 * Author: Timur Tabi <timur@freescale.com>
5 *
6 * Copyright 2007 Freescale Semiconductor, Inc.  This file is licensed under
7 * the terms of the GNU General Public License version 2.  This program
8 * is licensed "as is" without any warranty of any kind, whether express
9 * or implied.
10 *
11 * This driver adds support for UART devices via Freescale's QUICC Engine
12 * found on some Freescale SOCs.
13 *
14 * If Soft-UART support is needed but not already present, then this driver
15 * will request and upload the "Soft-UART" microcode upon probe.  The
16 * filename of the microcode should be fsl_qe_ucode_uart_X_YZ.bin, where "X"
17 * is the name of the SOC (e.g. 8323), and YZ is the revision of the SOC,
18 * (e.g. "11" for 1.1).
19 */
20
21#include <linux/module.h>
22#include <linux/serial.h>
23#include <linux/serial_core.h>
24#include <linux/slab.h>
25#include <linux/tty.h>
26#include <linux/tty_flip.h>
27#include <linux/io.h>
28#include <linux/of_address.h>
29#include <linux/of_irq.h>
30#include <linux/of_platform.h>
31#include <linux/dma-mapping.h>
32
33#include <linux/fs_uart_pd.h>
34#include <asm/ucc_slow.h>
35
36#include <linux/firmware.h>
37#include <asm/reg.h>
38
39/*
40 * The GUMR flag for Soft UART.  This would normally be defined in qe.h,
41 * but Soft-UART is a hack and we want to keep everything related to it in
42 * this file.
43 */
44#define UCC_SLOW_GUMR_H_SUART   	0x00004000      /* Soft-UART */
45
46/*
47 * soft_uart is 1 if we need to use Soft-UART mode
48 */
49static int soft_uart;
50/*
51 * firmware_loaded is 1 if the firmware has been loaded, 0 otherwise.
52 */
53static int firmware_loaded;
54
55/* Enable this macro to configure all serial ports in internal loopback
56   mode */
57/* #define LOOPBACK */
58
59/* The major and minor device numbers are defined in
60 * http://www.lanana.org/docs/device-list/devices-2.6+.txt.  For the QE
61 * UART, we have major number 204 and minor numbers 46 - 49, which are the
62 * same as for the CPM2.  This decision was made because no Freescale part
63 * has both a CPM and a QE.
64 */
65#define SERIAL_QE_MAJOR 204
66#define SERIAL_QE_MINOR 46
67
68/* Since we only have minor numbers 46 - 49, there is a hard limit of 4 ports */
69#define UCC_MAX_UART    4
70
71/* The number of buffer descriptors for receiving characters. */
72#define RX_NUM_FIFO     4
73
74/* The number of buffer descriptors for transmitting characters. */
75#define TX_NUM_FIFO     4
76
77/* The maximum size of the character buffer for a single RX BD. */
78#define RX_BUF_SIZE     32
79
80/* The maximum size of the character buffer for a single TX BD. */
81#define TX_BUF_SIZE     32
82
83/*
84 * The number of jiffies to wait after receiving a close command before the
85 * device is actually closed.  This allows the last few characters to be
86 * sent over the wire.
87 */
88#define UCC_WAIT_CLOSING 100
89
90struct ucc_uart_pram {
91	struct ucc_slow_pram common;
92	u8 res1[8];     	/* reserved */
93	__be16 maxidl;  	/* Maximum idle chars */
94	__be16 idlc;    	/* temp idle counter */
95	__be16 brkcr;   	/* Break count register */
96	__be16 parec;   	/* receive parity error counter */
97	__be16 frmec;   	/* receive framing error counter */
98	__be16 nosec;   	/* receive noise counter */
99	__be16 brkec;   	/* receive break condition counter */
100	__be16 brkln;   	/* last received break length */
101	__be16 uaddr[2];	/* UART address character 1 & 2 */
102	__be16 rtemp;   	/* Temp storage */
103	__be16 toseq;   	/* Transmit out of sequence char */
104	__be16 cchars[8];       /* control characters 1-8 */
105	__be16 rccm;    	/* receive control character mask */
106	__be16 rccr;    	/* receive control character register */
107	__be16 rlbc;    	/* receive last break character */
108	__be16 res2;    	/* reserved */
109	__be32 res3;    	/* reserved, should be cleared */
110	u8 res4;		/* reserved, should be cleared */
111	u8 res5[3];     	/* reserved, should be cleared */
112	__be32 res6;    	/* reserved, should be cleared */
113	__be32 res7;    	/* reserved, should be cleared */
114	__be32 res8;    	/* reserved, should be cleared */
115	__be32 res9;    	/* reserved, should be cleared */
116	__be32 res10;   	/* reserved, should be cleared */
117	__be32 res11;   	/* reserved, should be cleared */
118	__be32 res12;   	/* reserved, should be cleared */
119	__be32 res13;   	/* reserved, should be cleared */
120/* The rest is for Soft-UART only */
121	__be16 supsmr;  	/* 0x90, Shadow UPSMR */
122	__be16 res92;   	/* 0x92, reserved, initialize to 0 */
123	__be32 rx_state;	/* 0x94, RX state, initialize to 0 */
124	__be32 rx_cnt;  	/* 0x98, RX count, initialize to 0 */
125	u8 rx_length;   	/* 0x9C, Char length, set to 1+CL+PEN+1+SL */
126	u8 rx_bitmark;  	/* 0x9D, reserved, initialize to 0 */
127	u8 rx_temp_dlst_qe;     /* 0x9E, reserved, initialize to 0 */
128	u8 res14[0xBC - 0x9F];  /* reserved */
129	__be32 dump_ptr;	/* 0xBC, Dump pointer */
130	__be32 rx_frame_rem;    /* 0xC0, reserved, initialize to 0 */
131	u8 rx_frame_rem_size;   /* 0xC4, reserved, initialize to 0 */
132	u8 tx_mode;     	/* 0xC5, mode, 0=AHDLC, 1=UART */
133	__be16 tx_state;	/* 0xC6, TX state */
134	u8 res15[0xD0 - 0xC8];  /* reserved */
135	__be32 resD0;   	/* 0xD0, reserved, initialize to 0 */
136	u8 resD4;       	/* 0xD4, reserved, initialize to 0 */
137	__be16 resD5;   	/* 0xD5, reserved, initialize to 0 */
138} __attribute__ ((packed));
139
140/* SUPSMR definitions, for Soft-UART only */
141#define UCC_UART_SUPSMR_SL      	0x8000
142#define UCC_UART_SUPSMR_RPM_MASK	0x6000
143#define UCC_UART_SUPSMR_RPM_ODD 	0x0000
144#define UCC_UART_SUPSMR_RPM_LOW 	0x2000
145#define UCC_UART_SUPSMR_RPM_EVEN	0x4000
146#define UCC_UART_SUPSMR_RPM_HIGH	0x6000
147#define UCC_UART_SUPSMR_PEN     	0x1000
148#define UCC_UART_SUPSMR_TPM_MASK	0x0C00
149#define UCC_UART_SUPSMR_TPM_ODD 	0x0000
150#define UCC_UART_SUPSMR_TPM_LOW 	0x0400
151#define UCC_UART_SUPSMR_TPM_EVEN	0x0800
152#define UCC_UART_SUPSMR_TPM_HIGH	0x0C00
153#define UCC_UART_SUPSMR_FRZ     	0x0100
154#define UCC_UART_SUPSMR_UM_MASK 	0x00c0
155#define UCC_UART_SUPSMR_UM_NORMAL       0x0000
156#define UCC_UART_SUPSMR_UM_MAN_MULTI    0x0040
157#define UCC_UART_SUPSMR_UM_AUTO_MULTI   0x00c0
158#define UCC_UART_SUPSMR_CL_MASK 	0x0030
159#define UCC_UART_SUPSMR_CL_8    	0x0030
160#define UCC_UART_SUPSMR_CL_7    	0x0020
161#define UCC_UART_SUPSMR_CL_6    	0x0010
162#define UCC_UART_SUPSMR_CL_5    	0x0000
163
164#define UCC_UART_TX_STATE_AHDLC 	0x00
165#define UCC_UART_TX_STATE_UART  	0x01
166#define UCC_UART_TX_STATE_X1    	0x00
167#define UCC_UART_TX_STATE_X16   	0x80
168
169#define UCC_UART_PRAM_ALIGNMENT 0x100
170
171#define UCC_UART_SIZE_OF_BD     UCC_SLOW_SIZE_OF_BD
172#define NUM_CONTROL_CHARS       8
173
174/* Private per-port data structure */
175struct uart_qe_port {
176	struct uart_port port;
177	struct ucc_slow __iomem *uccp;
178	struct ucc_uart_pram __iomem *uccup;
179	struct ucc_slow_info us_info;
180	struct ucc_slow_private *us_private;
181	struct device_node *np;
182	unsigned int ucc_num;   /* First ucc is 0, not 1 */
183
184	u16 rx_nrfifos;
185	u16 rx_fifosize;
186	u16 tx_nrfifos;
187	u16 tx_fifosize;
188	int wait_closing;
189	u32 flags;
190	struct qe_bd *rx_bd_base;
191	struct qe_bd *rx_cur;
192	struct qe_bd *tx_bd_base;
193	struct qe_bd *tx_cur;
194	unsigned char *tx_buf;
195	unsigned char *rx_buf;
196	void *bd_virt;  	/* virtual address of the BD buffers */
197	dma_addr_t bd_dma_addr; /* bus address of the BD buffers */
198	unsigned int bd_size;   /* size of BD buffer space */
199};
200
201static struct uart_driver ucc_uart_driver = {
202	.owner  	= THIS_MODULE,
203	.driver_name    = "ucc_uart",
204	.dev_name       = "ttyQE",
205	.major  	= SERIAL_QE_MAJOR,
206	.minor  	= SERIAL_QE_MINOR,
207	.nr     	= UCC_MAX_UART,
208};
209
210/*
211 * Virtual to physical address translation.
212 *
213 * Given the virtual address for a character buffer, this function returns
214 * the physical (DMA) equivalent.
215 */
216static inline dma_addr_t cpu2qe_addr(void *addr, struct uart_qe_port *qe_port)
217{
218	if (likely((addr >= qe_port->bd_virt)) &&
219	    (addr < (qe_port->bd_virt + qe_port->bd_size)))
220		return qe_port->bd_dma_addr + (addr - qe_port->bd_virt);
221
222	/* something nasty happened */
223	printk(KERN_ERR "%s: addr=%p\n", __func__, addr);
224	BUG();
225	return 0;
226}
227
228/*
229 * Physical to virtual address translation.
230 *
231 * Given the physical (DMA) address for a character buffer, this function
232 * returns the virtual equivalent.
233 */
234static inline void *qe2cpu_addr(dma_addr_t addr, struct uart_qe_port *qe_port)
235{
236	/* sanity check */
237	if (likely((addr >= qe_port->bd_dma_addr) &&
238		   (addr < (qe_port->bd_dma_addr + qe_port->bd_size))))
239		return qe_port->bd_virt + (addr - qe_port->bd_dma_addr);
240
241	/* something nasty happened */
242	printk(KERN_ERR "%s: addr=%llx\n", __func__, (u64)addr);
243	BUG();
244	return NULL;
245}
246
247/*
248 * Return 1 if the QE is done transmitting all buffers for this port
249 *
250 * This function scans each BD in sequence.  If we find a BD that is not
251 * ready (READY=1), then we return 0 indicating that the QE is still sending
252 * data.  If we reach the last BD (WRAP=1), then we know we've scanned
253 * the entire list, and all BDs are done.
254 */
255static unsigned int qe_uart_tx_empty(struct uart_port *port)
256{
257	struct uart_qe_port *qe_port =
258		container_of(port, struct uart_qe_port, port);
259	struct qe_bd *bdp = qe_port->tx_bd_base;
260
261	while (1) {
262		if (in_be16(&bdp->status) & BD_SC_READY)
263			/* This BD is not done, so return "not done" */
264			return 0;
265
266		if (in_be16(&bdp->status) & BD_SC_WRAP)
267			/*
268			 * This BD is done and it's the last one, so return
269			 * "done"
270			 */
271			return 1;
272
273		bdp++;
274	}
275}
276
277/*
278 * Set the modem control lines
279 *
280 * Although the QE can control the modem control lines (e.g. CTS), we
281 * don't need that support. This function must exist, however, otherwise
282 * the kernel will panic.
283 */
284void qe_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
285{
286}
287
288/*
289 * Get the current modem control line status
290 *
291 * Although the QE can control the modem control lines (e.g. CTS), this
292 * driver currently doesn't support that, so we always return Carrier
293 * Detect, Data Set Ready, and Clear To Send.
294 */
295static unsigned int qe_uart_get_mctrl(struct uart_port *port)
296{
297	return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
298}
299
300/*
301 * Disable the transmit interrupt.
302 *
303 * Although this function is called "stop_tx", it does not actually stop
304 * transmission of data.  Instead, it tells the QE to not generate an
305 * interrupt when the UCC is finished sending characters.
306 */
307static void qe_uart_stop_tx(struct uart_port *port)
308{
309	struct uart_qe_port *qe_port =
310		container_of(port, struct uart_qe_port, port);
311
312	clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
313}
314
315/*
316 * Transmit as many characters to the HW as possible.
317 *
318 * This function will attempt to stuff of all the characters from the
319 * kernel's transmit buffer into TX BDs.
320 *
321 * A return value of non-zero indicates that it successfully stuffed all
322 * characters from the kernel buffer.
323 *
324 * A return value of zero indicates that there are still characters in the
325 * kernel's buffer that have not been transmitted, but there are no more BDs
326 * available.  This function should be called again after a BD has been made
327 * available.
328 */
329static int qe_uart_tx_pump(struct uart_qe_port *qe_port)
330{
331	struct qe_bd *bdp;
332	unsigned char *p;
333	unsigned int count;
334	struct uart_port *port = &qe_port->port;
335	struct circ_buf *xmit = &port->state->xmit;
336
337	bdp = qe_port->rx_cur;
338
339	/* Handle xon/xoff */
340	if (port->x_char) {
341		/* Pick next descriptor and fill from buffer */
342		bdp = qe_port->tx_cur;
343
344		p = qe2cpu_addr(bdp->buf, qe_port);
345
346		*p++ = port->x_char;
347		out_be16(&bdp->length, 1);
348		setbits16(&bdp->status, BD_SC_READY);
349		/* Get next BD. */
350		if (in_be16(&bdp->status) & BD_SC_WRAP)
351			bdp = qe_port->tx_bd_base;
352		else
353			bdp++;
354		qe_port->tx_cur = bdp;
355
356		port->icount.tx++;
357		port->x_char = 0;
358		return 1;
359	}
360
361	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
362		qe_uart_stop_tx(port);
363		return 0;
364	}
365
366	/* Pick next descriptor and fill from buffer */
367	bdp = qe_port->tx_cur;
368
369	while (!(in_be16(&bdp->status) & BD_SC_READY) &&
370	       (xmit->tail != xmit->head)) {
371		count = 0;
372		p = qe2cpu_addr(bdp->buf, qe_port);
373		while (count < qe_port->tx_fifosize) {
374			*p++ = xmit->buf[xmit->tail];
375			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
376			port->icount.tx++;
377			count++;
378			if (xmit->head == xmit->tail)
379				break;
380		}
381
382		out_be16(&bdp->length, count);
383		setbits16(&bdp->status, BD_SC_READY);
384
385		/* Get next BD. */
386		if (in_be16(&bdp->status) & BD_SC_WRAP)
387			bdp = qe_port->tx_bd_base;
388		else
389			bdp++;
390	}
391	qe_port->tx_cur = bdp;
392
393	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
394		uart_write_wakeup(port);
395
396	if (uart_circ_empty(xmit)) {
397		/* The kernel buffer is empty, so turn off TX interrupts.  We
398		   don't need to be told when the QE is finished transmitting
399		   the data. */
400		qe_uart_stop_tx(port);
401		return 0;
402	}
403
404	return 1;
405}
406
407/*
408 * Start transmitting data
409 *
410 * This function will start transmitting any available data, if the port
411 * isn't already transmitting data.
412 */
413static void qe_uart_start_tx(struct uart_port *port)
414{
415	struct uart_qe_port *qe_port =
416		container_of(port, struct uart_qe_port, port);
417
418	/* If we currently are transmitting, then just return */
419	if (in_be16(&qe_port->uccp->uccm) & UCC_UART_UCCE_TX)
420		return;
421
422	/* Otherwise, pump the port and start transmission */
423	if (qe_uart_tx_pump(qe_port))
424		setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
425}
426
427/*
428 * Stop transmitting data
429 */
430static void qe_uart_stop_rx(struct uart_port *port)
431{
432	struct uart_qe_port *qe_port =
433		container_of(port, struct uart_qe_port, port);
434
435	clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
436}
437
438/* Start or stop sending  break signal
439 *
440 * This function controls the sending of a break signal.  If break_state=1,
441 * then we start sending a break signal.  If break_state=0, then we stop
442 * sending the break signal.
443 */
444static void qe_uart_break_ctl(struct uart_port *port, int break_state)
445{
446	struct uart_qe_port *qe_port =
447		container_of(port, struct uart_qe_port, port);
448
449	if (break_state)
450		ucc_slow_stop_tx(qe_port->us_private);
451	else
452		ucc_slow_restart_tx(qe_port->us_private);
453}
454
455/* ISR helper function for receiving character.
456 *
457 * This function is called by the ISR to handling receiving characters
458 */
459static void qe_uart_int_rx(struct uart_qe_port *qe_port)
460{
461	int i;
462	unsigned char ch, *cp;
463	struct uart_port *port = &qe_port->port;
464	struct tty_port *tport = &port->state->port;
465	struct qe_bd *bdp;
466	u16 status;
467	unsigned int flg;
468
469	/* Just loop through the closed BDs and copy the characters into
470	 * the buffer.
471	 */
472	bdp = qe_port->rx_cur;
473	while (1) {
474		status = in_be16(&bdp->status);
475
476		/* If this one is empty, then we assume we've read them all */
477		if (status & BD_SC_EMPTY)
478			break;
479
480		/* get number of characters, and check space in RX buffer */
481		i = in_be16(&bdp->length);
482
483		/* If we don't have enough room in RX buffer for the entire BD,
484		 * then we try later, which will be the next RX interrupt.
485		 */
486		if (tty_buffer_request_room(tport, i) < i) {
487			dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n");
488			return;
489		}
490
491		/* get pointer */
492		cp = qe2cpu_addr(bdp->buf, qe_port);
493
494		/* loop through the buffer */
495		while (i-- > 0) {
496			ch = *cp++;
497			port->icount.rx++;
498			flg = TTY_NORMAL;
499
500			if (!i && status &
501			    (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
502				goto handle_error;
503			if (uart_handle_sysrq_char(port, ch))
504				continue;
505
506error_return:
507			tty_insert_flip_char(tport, ch, flg);
508
509		}
510
511		/* This BD is ready to be used again. Clear status. get next */
512		clrsetbits_be16(&bdp->status, BD_SC_BR | BD_SC_FR | BD_SC_PR |
513			BD_SC_OV | BD_SC_ID, BD_SC_EMPTY);
514		if (in_be16(&bdp->status) & BD_SC_WRAP)
515			bdp = qe_port->rx_bd_base;
516		else
517			bdp++;
518
519	}
520
521	/* Write back buffer pointer */
522	qe_port->rx_cur = bdp;
523
524	/* Activate BH processing */
525	tty_flip_buffer_push(tport);
526
527	return;
528
529	/* Error processing */
530
531handle_error:
532	/* Statistics */
533	if (status & BD_SC_BR)
534		port->icount.brk++;
535	if (status & BD_SC_PR)
536		port->icount.parity++;
537	if (status & BD_SC_FR)
538		port->icount.frame++;
539	if (status & BD_SC_OV)
540		port->icount.overrun++;
541
542	/* Mask out ignored conditions */
543	status &= port->read_status_mask;
544
545	/* Handle the remaining ones */
546	if (status & BD_SC_BR)
547		flg = TTY_BREAK;
548	else if (status & BD_SC_PR)
549		flg = TTY_PARITY;
550	else if (status & BD_SC_FR)
551		flg = TTY_FRAME;
552
553	/* Overrun does not affect the current character ! */
554	if (status & BD_SC_OV)
555		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
556#ifdef SUPPORT_SYSRQ
557	port->sysrq = 0;
558#endif
559	goto error_return;
560}
561
562/* Interrupt handler
563 *
564 * This interrupt handler is called after a BD is processed.
565 */
566static irqreturn_t qe_uart_int(int irq, void *data)
567{
568	struct uart_qe_port *qe_port = (struct uart_qe_port *) data;
569	struct ucc_slow __iomem *uccp = qe_port->uccp;
570	u16 events;
571
572	/* Clear the interrupts */
573	events = in_be16(&uccp->ucce);
574	out_be16(&uccp->ucce, events);
575
576	if (events & UCC_UART_UCCE_BRKE)
577		uart_handle_break(&qe_port->port);
578
579	if (events & UCC_UART_UCCE_RX)
580		qe_uart_int_rx(qe_port);
581
582	if (events & UCC_UART_UCCE_TX)
583		qe_uart_tx_pump(qe_port);
584
585	return events ? IRQ_HANDLED : IRQ_NONE;
586}
587
588/* Initialize buffer descriptors
589 *
590 * This function initializes all of the RX and TX buffer descriptors.
591 */
592static void qe_uart_initbd(struct uart_qe_port *qe_port)
593{
594	int i;
595	void *bd_virt;
596	struct qe_bd *bdp;
597
598	/* Set the physical address of the host memory buffers in the buffer
599	 * descriptors, and the virtual address for us to work with.
600	 */
601	bd_virt = qe_port->bd_virt;
602	bdp = qe_port->rx_bd_base;
603	qe_port->rx_cur = qe_port->rx_bd_base;
604	for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) {
605		out_be16(&bdp->status, BD_SC_EMPTY | BD_SC_INTRPT);
606		out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
607		out_be16(&bdp->length, 0);
608		bd_virt += qe_port->rx_fifosize;
609		bdp++;
610	}
611
612	/* */
613	out_be16(&bdp->status, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
614	out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
615	out_be16(&bdp->length, 0);
616
617	/* Set the physical address of the host memory
618	 * buffers in the buffer descriptors, and the
619	 * virtual address for us to work with.
620	 */
621	bd_virt = qe_port->bd_virt +
622		L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
623	qe_port->tx_cur = qe_port->tx_bd_base;
624	bdp = qe_port->tx_bd_base;
625	for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) {
626		out_be16(&bdp->status, BD_SC_INTRPT);
627		out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
628		out_be16(&bdp->length, 0);
629		bd_virt += qe_port->tx_fifosize;
630		bdp++;
631	}
632
633	/* Loopback requires the preamble bit to be set on the first TX BD */
634#ifdef LOOPBACK
635	setbits16(&qe_port->tx_cur->status, BD_SC_P);
636#endif
637
638	out_be16(&bdp->status, BD_SC_WRAP | BD_SC_INTRPT);
639	out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
640	out_be16(&bdp->length, 0);
641}
642
643/*
644 * Initialize a UCC for UART.
645 *
646 * This function configures a given UCC to be used as a UART device. Basic
647 * UCC initialization is handled in qe_uart_request_port().  This function
648 * does all the UART-specific stuff.
649 */
650static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
651{
652	u32 cecr_subblock;
653	struct ucc_slow __iomem *uccp = qe_port->uccp;
654	struct ucc_uart_pram *uccup = qe_port->uccup;
655
656	unsigned int i;
657
658	/* First, disable TX and RX in the UCC */
659	ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
660
661	/* Program the UCC UART parameter RAM */
662	out_8(&uccup->common.rbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
663	out_8(&uccup->common.tbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
664	out_be16(&uccup->common.mrblr, qe_port->rx_fifosize);
665	out_be16(&uccup->maxidl, 0x10);
666	out_be16(&uccup->brkcr, 1);
667	out_be16(&uccup->parec, 0);
668	out_be16(&uccup->frmec, 0);
669	out_be16(&uccup->nosec, 0);
670	out_be16(&uccup->brkec, 0);
671	out_be16(&uccup->uaddr[0], 0);
672	out_be16(&uccup->uaddr[1], 0);
673	out_be16(&uccup->toseq, 0);
674	for (i = 0; i < 8; i++)
675		out_be16(&uccup->cchars[i], 0xC000);
676	out_be16(&uccup->rccm, 0xc0ff);
677
678	/* Configure the GUMR registers for UART */
679	if (soft_uart) {
680		/* Soft-UART requires a 1X multiplier for TX */
681		clrsetbits_be32(&uccp->gumr_l,
682			UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
683			UCC_SLOW_GUMR_L_RDCR_MASK,
684			UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 |
685			UCC_SLOW_GUMR_L_RDCR_16);
686
687		clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
688			UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
689	} else {
690		clrsetbits_be32(&uccp->gumr_l,
691			UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
692			UCC_SLOW_GUMR_L_RDCR_MASK,
693			UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 |
694			UCC_SLOW_GUMR_L_RDCR_16);
695
696		clrsetbits_be32(&uccp->gumr_h,
697			UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX,
698			UCC_SLOW_GUMR_H_RFW);
699	}
700
701#ifdef LOOPBACK
702	clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
703		UCC_SLOW_GUMR_L_DIAG_LOOP);
704	clrsetbits_be32(&uccp->gumr_h,
705		UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN,
706		UCC_SLOW_GUMR_H_CDS);
707#endif
708
709	/* Disable rx interrupts  and clear all pending events.  */
710	out_be16(&uccp->uccm, 0);
711	out_be16(&uccp->ucce, 0xffff);
712	out_be16(&uccp->udsr, 0x7e7e);
713
714	/* Initialize UPSMR */
715	out_be16(&uccp->upsmr, 0);
716
717	if (soft_uart) {
718		out_be16(&uccup->supsmr, 0x30);
719		out_be16(&uccup->res92, 0);
720		out_be32(&uccup->rx_state, 0);
721		out_be32(&uccup->rx_cnt, 0);
722		out_8(&uccup->rx_bitmark, 0);
723		out_8(&uccup->rx_length, 10);
724		out_be32(&uccup->dump_ptr, 0x4000);
725		out_8(&uccup->rx_temp_dlst_qe, 0);
726		out_be32(&uccup->rx_frame_rem, 0);
727		out_8(&uccup->rx_frame_rem_size, 0);
728		/* Soft-UART requires TX to be 1X */
729		out_8(&uccup->tx_mode,
730			UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1);
731		out_be16(&uccup->tx_state, 0);
732		out_8(&uccup->resD4, 0);
733		out_be16(&uccup->resD5, 0);
734
735		/* Set UART mode.
736		 * Enable receive and transmit.
737		 */
738
739		/* From the microcode errata:
740		 * 1.GUMR_L register, set mode=0010 (QMC).
741		 * 2.Set GUMR_H[17] bit. (UART/AHDLC mode).
742		 * 3.Set GUMR_H[19:20] (Transparent mode)
743		 * 4.Clear GUMR_H[26] (RFW)
744		 * ...
745		 * 6.Receiver must use 16x over sampling
746		 */
747		clrsetbits_be32(&uccp->gumr_l,
748			UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
749			UCC_SLOW_GUMR_L_RDCR_MASK,
750			UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 |
751			UCC_SLOW_GUMR_L_RDCR_16);
752
753		clrsetbits_be32(&uccp->gumr_h,
754			UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN,
755			UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX |
756			UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL);
757
758#ifdef LOOPBACK
759		clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
760				UCC_SLOW_GUMR_L_DIAG_LOOP);
761		clrbits32(&uccp->gumr_h, UCC_SLOW_GUMR_H_CTSP |
762			  UCC_SLOW_GUMR_H_CDS);
763#endif
764
765		cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
766		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
767			QE_CR_PROTOCOL_UNSPECIFIED, 0);
768	} else {
769		cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
770		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
771			QE_CR_PROTOCOL_UART, 0);
772	}
773}
774
775/*
776 * Initialize the port.
777 */
778static int qe_uart_startup(struct uart_port *port)
779{
780	struct uart_qe_port *qe_port =
781		container_of(port, struct uart_qe_port, port);
782	int ret;
783
784	/*
785	 * If we're using Soft-UART mode, then we need to make sure the
786	 * firmware has been uploaded first.
787	 */
788	if (soft_uart && !firmware_loaded) {
789		dev_err(port->dev, "Soft-UART firmware not uploaded\n");
790		return -ENODEV;
791	}
792
793	qe_uart_initbd(qe_port);
794	qe_uart_init_ucc(qe_port);
795
796	/* Install interrupt handler. */
797	ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart",
798		qe_port);
799	if (ret) {
800		dev_err(port->dev, "could not claim IRQ %u\n", port->irq);
801		return ret;
802	}
803
804	/* Startup rx-int */
805	setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
806	ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX);
807
808	return 0;
809}
810
811/*
812 * Shutdown the port.
813 */
814static void qe_uart_shutdown(struct uart_port *port)
815{
816	struct uart_qe_port *qe_port =
817		container_of(port, struct uart_qe_port, port);
818	struct ucc_slow __iomem *uccp = qe_port->uccp;
819	unsigned int timeout = 20;
820
821	/* Disable RX and TX */
822
823	/* Wait for all the BDs marked sent */
824	while (!qe_uart_tx_empty(port)) {
825		if (!--timeout) {
826			dev_warn(port->dev, "shutdown timeout\n");
827			break;
828		}
829		set_current_state(TASK_UNINTERRUPTIBLE);
830		schedule_timeout(2);
831	}
832
833	if (qe_port->wait_closing) {
834		/* Wait a bit longer */
835		set_current_state(TASK_UNINTERRUPTIBLE);
836		schedule_timeout(qe_port->wait_closing);
837	}
838
839	/* Stop uarts */
840	ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
841	clrbits16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX);
842
843	/* Shut them really down and reinit buffer descriptors */
844	ucc_slow_graceful_stop_tx(qe_port->us_private);
845	qe_uart_initbd(qe_port);
846
847	free_irq(port->irq, qe_port);
848}
849
850/*
851 * Set the serial port parameters.
852 */
853static void qe_uart_set_termios(struct uart_port *port,
854				struct ktermios *termios, struct ktermios *old)
855{
856	struct uart_qe_port *qe_port =
857		container_of(port, struct uart_qe_port, port);
858	struct ucc_slow __iomem *uccp = qe_port->uccp;
859	unsigned int baud;
860	unsigned long flags;
861	u16 upsmr = in_be16(&uccp->upsmr);
862	struct ucc_uart_pram __iomem *uccup = qe_port->uccup;
863	u16 supsmr = in_be16(&uccup->supsmr);
864	u8 char_length = 2; /* 1 + CL + PEN + 1 + SL */
865
866	/* Character length programmed into the mode register is the
867	 * sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
868	 * 1 or 2 stop bits, minus 1.
869	 * The value 'bits' counts this for us.
870	 */
871
872	/* byte size */
873	upsmr &= UCC_UART_UPSMR_CL_MASK;
874	supsmr &= UCC_UART_SUPSMR_CL_MASK;
875
876	switch (termios->c_cflag & CSIZE) {
877	case CS5:
878		upsmr |= UCC_UART_UPSMR_CL_5;
879		supsmr |= UCC_UART_SUPSMR_CL_5;
880		char_length += 5;
881		break;
882	case CS6:
883		upsmr |= UCC_UART_UPSMR_CL_6;
884		supsmr |= UCC_UART_SUPSMR_CL_6;
885		char_length += 6;
886		break;
887	case CS7:
888		upsmr |= UCC_UART_UPSMR_CL_7;
889		supsmr |= UCC_UART_SUPSMR_CL_7;
890		char_length += 7;
891		break;
892	default:	/* case CS8 */
893		upsmr |= UCC_UART_UPSMR_CL_8;
894		supsmr |= UCC_UART_SUPSMR_CL_8;
895		char_length += 8;
896		break;
897	}
898
899	/* If CSTOPB is set, we want two stop bits */
900	if (termios->c_cflag & CSTOPB) {
901		upsmr |= UCC_UART_UPSMR_SL;
902		supsmr |= UCC_UART_SUPSMR_SL;
903		char_length++;  /* + SL */
904	}
905
906	if (termios->c_cflag & PARENB) {
907		upsmr |= UCC_UART_UPSMR_PEN;
908		supsmr |= UCC_UART_SUPSMR_PEN;
909		char_length++;  /* + PEN */
910
911		if (!(termios->c_cflag & PARODD)) {
912			upsmr &= ~(UCC_UART_UPSMR_RPM_MASK |
913				   UCC_UART_UPSMR_TPM_MASK);
914			upsmr |= UCC_UART_UPSMR_RPM_EVEN |
915				UCC_UART_UPSMR_TPM_EVEN;
916			supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK |
917				    UCC_UART_SUPSMR_TPM_MASK);
918			supsmr |= UCC_UART_SUPSMR_RPM_EVEN |
919				UCC_UART_SUPSMR_TPM_EVEN;
920		}
921	}
922
923	/*
924	 * Set up parity check flag
925	 */
926	port->read_status_mask = BD_SC_EMPTY | BD_SC_OV;
927	if (termios->c_iflag & INPCK)
928		port->read_status_mask |= BD_SC_FR | BD_SC_PR;
929	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
930		port->read_status_mask |= BD_SC_BR;
931
932	/*
933	 * Characters to ignore
934	 */
935	port->ignore_status_mask = 0;
936	if (termios->c_iflag & IGNPAR)
937		port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
938	if (termios->c_iflag & IGNBRK) {
939		port->ignore_status_mask |= BD_SC_BR;
940		/*
941		 * If we're ignore parity and break indicators, ignore
942		 * overruns too.  (For real raw support).
943		 */
944		if (termios->c_iflag & IGNPAR)
945			port->ignore_status_mask |= BD_SC_OV;
946	}
947	/*
948	 * !!! ignore all characters if CREAD is not set
949	 */
950	if ((termios->c_cflag & CREAD) == 0)
951		port->read_status_mask &= ~BD_SC_EMPTY;
952
953	baud = uart_get_baud_rate(port, termios, old, 0, 115200);
954
955	/* Do we really need a spinlock here? */
956	spin_lock_irqsave(&port->lock, flags);
957
958	/* Update the per-port timeout. */
959	uart_update_timeout(port, termios->c_cflag, baud);
960
961	out_be16(&uccp->upsmr, upsmr);
962	if (soft_uart) {
963		out_be16(&uccup->supsmr, supsmr);
964		out_8(&uccup->rx_length, char_length);
965
966		/* Soft-UART requires a 1X multiplier for TX */
967		qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
968		qe_setbrg(qe_port->us_info.tx_clock, baud, 1);
969	} else {
970		qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
971		qe_setbrg(qe_port->us_info.tx_clock, baud, 16);
972	}
973
974	spin_unlock_irqrestore(&port->lock, flags);
975}
976
977/*
978 * Return a pointer to a string that describes what kind of port this is.
979 */
980static const char *qe_uart_type(struct uart_port *port)
981{
982	return "QE";
983}
984
985/*
986 * Allocate any memory and I/O resources required by the port.
987 */
988static int qe_uart_request_port(struct uart_port *port)
989{
990	int ret;
991	struct uart_qe_port *qe_port =
992		container_of(port, struct uart_qe_port, port);
993	struct ucc_slow_info *us_info = &qe_port->us_info;
994	struct ucc_slow_private *uccs;
995	unsigned int rx_size, tx_size;
996	void *bd_virt;
997	dma_addr_t bd_dma_addr = 0;
998
999	ret = ucc_slow_init(us_info, &uccs);
1000	if (ret) {
1001		dev_err(port->dev, "could not initialize UCC%u\n",
1002		       qe_port->ucc_num);
1003		return ret;
1004	}
1005
1006	qe_port->us_private = uccs;
1007	qe_port->uccp = uccs->us_regs;
1008	qe_port->uccup = (struct ucc_uart_pram *) uccs->us_pram;
1009	qe_port->rx_bd_base = uccs->rx_bd;
1010	qe_port->tx_bd_base = uccs->tx_bd;
1011
1012	/*
1013	 * Allocate the transmit and receive data buffers.
1014	 */
1015
1016	rx_size = L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
1017	tx_size = L1_CACHE_ALIGN(qe_port->tx_nrfifos * qe_port->tx_fifosize);
1018
1019	bd_virt = dma_alloc_coherent(port->dev, rx_size + tx_size, &bd_dma_addr,
1020		GFP_KERNEL);
1021	if (!bd_virt) {
1022		dev_err(port->dev, "could not allocate buffer descriptors\n");
1023		return -ENOMEM;
1024	}
1025
1026	qe_port->bd_virt = bd_virt;
1027	qe_port->bd_dma_addr = bd_dma_addr;
1028	qe_port->bd_size = rx_size + tx_size;
1029
1030	qe_port->rx_buf = bd_virt;
1031	qe_port->tx_buf = qe_port->rx_buf + rx_size;
1032
1033	return 0;
1034}
1035
1036/*
1037 * Configure the port.
1038 *
1039 * We say we're a CPM-type port because that's mostly true.  Once the device
1040 * is configured, this driver operates almost identically to the CPM serial
1041 * driver.
1042 */
1043static void qe_uart_config_port(struct uart_port *port, int flags)
1044{
1045	if (flags & UART_CONFIG_TYPE) {
1046		port->type = PORT_CPM;
1047		qe_uart_request_port(port);
1048	}
1049}
1050
1051/*
1052 * Release any memory and I/O resources that were allocated in
1053 * qe_uart_request_port().
1054 */
1055static void qe_uart_release_port(struct uart_port *port)
1056{
1057	struct uart_qe_port *qe_port =
1058		container_of(port, struct uart_qe_port, port);
1059	struct ucc_slow_private *uccs = qe_port->us_private;
1060
1061	dma_free_coherent(port->dev, qe_port->bd_size, qe_port->bd_virt,
1062			  qe_port->bd_dma_addr);
1063
1064	ucc_slow_free(uccs);
1065}
1066
1067/*
1068 * Verify that the data in serial_struct is suitable for this device.
1069 */
1070static int qe_uart_verify_port(struct uart_port *port,
1071			       struct serial_struct *ser)
1072{
1073	if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
1074		return -EINVAL;
1075
1076	if (ser->irq < 0 || ser->irq >= nr_irqs)
1077		return -EINVAL;
1078
1079	if (ser->baud_base < 9600)
1080		return -EINVAL;
1081
1082	return 0;
1083}
1084/* UART operations
1085 *
1086 * Details on these functions can be found in Documentation/serial/driver
1087 */
1088static struct uart_ops qe_uart_pops = {
1089	.tx_empty       = qe_uart_tx_empty,
1090	.set_mctrl      = qe_uart_set_mctrl,
1091	.get_mctrl      = qe_uart_get_mctrl,
1092	.stop_tx	= qe_uart_stop_tx,
1093	.start_tx       = qe_uart_start_tx,
1094	.stop_rx	= qe_uart_stop_rx,
1095	.break_ctl      = qe_uart_break_ctl,
1096	.startup	= qe_uart_startup,
1097	.shutdown       = qe_uart_shutdown,
1098	.set_termios    = qe_uart_set_termios,
1099	.type   	= qe_uart_type,
1100	.release_port   = qe_uart_release_port,
1101	.request_port   = qe_uart_request_port,
1102	.config_port    = qe_uart_config_port,
1103	.verify_port    = qe_uart_verify_port,
1104};
1105
1106/*
1107 * Obtain the SOC model number and revision level
1108 *
1109 * This function parses the device tree to obtain the SOC model.  It then
1110 * reads the SVR register to the revision.
1111 *
1112 * The device tree stores the SOC model two different ways.
1113 *
1114 * The new way is:
1115 *
1116 *      	cpu@0 {
1117 *      		compatible = "PowerPC,8323";
1118 *      		device_type = "cpu";
1119 *      		...
1120 *
1121 *
1122 * The old way is:
1123 *      	 PowerPC,8323@0 {
1124 *      		device_type = "cpu";
1125 *      		...
1126 *
1127 * This code first checks the new way, and then the old way.
1128 */
1129static unsigned int soc_info(unsigned int *rev_h, unsigned int *rev_l)
1130{
1131	struct device_node *np;
1132	const char *soc_string;
1133	unsigned int svr;
1134	unsigned int soc;
1135
1136	/* Find the CPU node */
1137	np = of_find_node_by_type(NULL, "cpu");
1138	if (!np)
1139		return 0;
1140	/* Find the compatible property */
1141	soc_string = of_get_property(np, "compatible", NULL);
1142	if (!soc_string)
1143		/* No compatible property, so try the name. */
1144		soc_string = np->name;
1145
1146	/* Extract the SOC number from the "PowerPC," string */
1147	if ((sscanf(soc_string, "PowerPC,%u", &soc) != 1) || !soc)
1148		return 0;
1149
1150	/* Get the revision from the SVR */
1151	svr = mfspr(SPRN_SVR);
1152	*rev_h = (svr >> 4) & 0xf;
1153	*rev_l = svr & 0xf;
1154
1155	return soc;
1156}
1157
1158/*
1159 * requst_firmware_nowait() callback function
1160 *
1161 * This function is called by the kernel when a firmware is made available,
1162 * or if it times out waiting for the firmware.
1163 */
1164static void uart_firmware_cont(const struct firmware *fw, void *context)
1165{
1166	struct qe_firmware *firmware;
1167	struct device *dev = context;
1168	int ret;
1169
1170	if (!fw) {
1171		dev_err(dev, "firmware not found\n");
1172		return;
1173	}
1174
1175	firmware = (struct qe_firmware *) fw->data;
1176
1177	if (firmware->header.length != fw->size) {
1178		dev_err(dev, "invalid firmware\n");
1179		goto out;
1180	}
1181
1182	ret = qe_upload_firmware(firmware);
1183	if (ret) {
1184		dev_err(dev, "could not load firmware\n");
1185		goto out;
1186	}
1187
1188	firmware_loaded = 1;
1189 out:
1190	release_firmware(fw);
1191}
1192
1193static int ucc_uart_probe(struct platform_device *ofdev)
1194{
1195	struct device_node *np = ofdev->dev.of_node;
1196	const unsigned int *iprop;      /* Integer OF properties */
1197	const char *sprop;      /* String OF properties */
1198	struct uart_qe_port *qe_port = NULL;
1199	struct resource res;
1200	int ret;
1201
1202	/*
1203	 * Determine if we need Soft-UART mode
1204	 */
1205	if (of_find_property(np, "soft-uart", NULL)) {
1206		dev_dbg(&ofdev->dev, "using Soft-UART mode\n");
1207		soft_uart = 1;
1208	}
1209
1210	/*
1211	 * If we are using Soft-UART, determine if we need to upload the
1212	 * firmware, too.
1213	 */
1214	if (soft_uart) {
1215		struct qe_firmware_info *qe_fw_info;
1216
1217		qe_fw_info = qe_get_firmware_info();
1218
1219		/* Check if the firmware has been uploaded. */
1220		if (qe_fw_info && strstr(qe_fw_info->id, "Soft-UART")) {
1221			firmware_loaded = 1;
1222		} else {
1223			char filename[32];
1224			unsigned int soc;
1225			unsigned int rev_h;
1226			unsigned int rev_l;
1227
1228			soc = soc_info(&rev_h, &rev_l);
1229			if (!soc) {
1230				dev_err(&ofdev->dev, "unknown CPU model\n");
1231				return -ENXIO;
1232			}
1233			sprintf(filename, "fsl_qe_ucode_uart_%u_%u%u.bin",
1234				soc, rev_h, rev_l);
1235
1236			dev_info(&ofdev->dev, "waiting for firmware %s\n",
1237				filename);
1238
1239			/*
1240			 * We call request_firmware_nowait instead of
1241			 * request_firmware so that the driver can load and
1242			 * initialize the ports without holding up the rest of
1243			 * the kernel.  If hotplug support is enabled in the
1244			 * kernel, then we use it.
1245			 */
1246			ret = request_firmware_nowait(THIS_MODULE,
1247				FW_ACTION_HOTPLUG, filename, &ofdev->dev,
1248				GFP_KERNEL, &ofdev->dev, uart_firmware_cont);
1249			if (ret) {
1250				dev_err(&ofdev->dev,
1251					"could not load firmware %s\n",
1252					filename);
1253				return ret;
1254			}
1255		}
1256	}
1257
1258	qe_port = kzalloc(sizeof(struct uart_qe_port), GFP_KERNEL);
1259	if (!qe_port) {
1260		dev_err(&ofdev->dev, "can't allocate QE port structure\n");
1261		return -ENOMEM;
1262	}
1263
1264	/* Search for IRQ and mapbase */
1265	ret = of_address_to_resource(np, 0, &res);
1266	if (ret) {
1267		dev_err(&ofdev->dev, "missing 'reg' property in device tree\n");
1268		goto out_free;
1269	}
1270	if (!res.start) {
1271		dev_err(&ofdev->dev, "invalid 'reg' property in device tree\n");
1272		ret = -EINVAL;
1273		goto out_free;
1274	}
1275	qe_port->port.mapbase = res.start;
1276
1277	/* Get the UCC number (device ID) */
1278	/* UCCs are numbered 1-7 */
1279	iprop = of_get_property(np, "cell-index", NULL);
1280	if (!iprop) {
1281		iprop = of_get_property(np, "device-id", NULL);
1282		if (!iprop) {
1283			dev_err(&ofdev->dev, "UCC is unspecified in "
1284				"device tree\n");
1285			ret = -EINVAL;
1286			goto out_free;
1287		}
1288	}
1289
1290	if ((*iprop < 1) || (*iprop > UCC_MAX_NUM)) {
1291		dev_err(&ofdev->dev, "no support for UCC%u\n", *iprop);
1292		ret = -ENODEV;
1293		goto out_free;
1294	}
1295	qe_port->ucc_num = *iprop - 1;
1296
1297	/*
1298	 * In the future, we should not require the BRG to be specified in the
1299	 * device tree.  If no clock-source is specified, then just pick a BRG
1300	 * to use.  This requires a new QE library function that manages BRG
1301	 * assignments.
1302	 */
1303
1304	sprop = of_get_property(np, "rx-clock-name", NULL);
1305	if (!sprop) {
1306		dev_err(&ofdev->dev, "missing rx-clock-name in device tree\n");
1307		ret = -ENODEV;
1308		goto out_free;
1309	}
1310
1311	qe_port->us_info.rx_clock = qe_clock_source(sprop);
1312	if ((qe_port->us_info.rx_clock < QE_BRG1) ||
1313	    (qe_port->us_info.rx_clock > QE_BRG16)) {
1314		dev_err(&ofdev->dev, "rx-clock-name must be a BRG for UART\n");
1315		ret = -ENODEV;
1316		goto out_free;
1317	}
1318
1319#ifdef LOOPBACK
1320	/* In internal loopback mode, TX and RX must use the same clock */
1321	qe_port->us_info.tx_clock = qe_port->us_info.rx_clock;
1322#else
1323	sprop = of_get_property(np, "tx-clock-name", NULL);
1324	if (!sprop) {
1325		dev_err(&ofdev->dev, "missing tx-clock-name in device tree\n");
1326		ret = -ENODEV;
1327		goto out_free;
1328	}
1329	qe_port->us_info.tx_clock = qe_clock_source(sprop);
1330#endif
1331	if ((qe_port->us_info.tx_clock < QE_BRG1) ||
1332	    (qe_port->us_info.tx_clock > QE_BRG16)) {
1333		dev_err(&ofdev->dev, "tx-clock-name must be a BRG for UART\n");
1334		ret = -ENODEV;
1335		goto out_free;
1336	}
1337
1338	/* Get the port number, numbered 0-3 */
1339	iprop = of_get_property(np, "port-number", NULL);
1340	if (!iprop) {
1341		dev_err(&ofdev->dev, "missing port-number in device tree\n");
1342		ret = -EINVAL;
1343		goto out_free;
1344	}
1345	qe_port->port.line = *iprop;
1346	if (qe_port->port.line >= UCC_MAX_UART) {
1347		dev_err(&ofdev->dev, "port-number must be 0-%u\n",
1348			UCC_MAX_UART - 1);
1349		ret = -EINVAL;
1350		goto out_free;
1351	}
1352
1353	qe_port->port.irq = irq_of_parse_and_map(np, 0);
1354	if (qe_port->port.irq == 0) {
1355		dev_err(&ofdev->dev, "could not map IRQ for UCC%u\n",
1356		       qe_port->ucc_num + 1);
1357		ret = -EINVAL;
1358		goto out_free;
1359	}
1360
1361	/*
1362	 * Newer device trees have an "fsl,qe" compatible property for the QE
1363	 * node, but we still need to support older device trees.
1364	 */
1365	np = of_find_compatible_node(NULL, NULL, "fsl,qe");
1366	if (!np) {
1367		np = of_find_node_by_type(NULL, "qe");
1368		if (!np) {
1369			dev_err(&ofdev->dev, "could not find 'qe' node\n");
1370			ret = -EINVAL;
1371			goto out_free;
1372		}
1373	}
1374
1375	iprop = of_get_property(np, "brg-frequency", NULL);
1376	if (!iprop) {
1377		dev_err(&ofdev->dev,
1378		       "missing brg-frequency in device tree\n");
1379		ret = -EINVAL;
1380		goto out_np;
1381	}
1382
1383	if (*iprop)
1384		qe_port->port.uartclk = *iprop;
1385	else {
1386		/*
1387		 * Older versions of U-Boot do not initialize the brg-frequency
1388		 * property, so in this case we assume the BRG frequency is
1389		 * half the QE bus frequency.
1390		 */
1391		iprop = of_get_property(np, "bus-frequency", NULL);
1392		if (!iprop) {
1393			dev_err(&ofdev->dev,
1394				"missing QE bus-frequency in device tree\n");
1395			ret = -EINVAL;
1396			goto out_np;
1397		}
1398		if (*iprop)
1399			qe_port->port.uartclk = *iprop / 2;
1400		else {
1401			dev_err(&ofdev->dev,
1402				"invalid QE bus-frequency in device tree\n");
1403			ret = -EINVAL;
1404			goto out_np;
1405		}
1406	}
1407
1408	spin_lock_init(&qe_port->port.lock);
1409	qe_port->np = np;
1410	qe_port->port.dev = &ofdev->dev;
1411	qe_port->port.ops = &qe_uart_pops;
1412	qe_port->port.iotype = UPIO_MEM;
1413
1414	qe_port->tx_nrfifos = TX_NUM_FIFO;
1415	qe_port->tx_fifosize = TX_BUF_SIZE;
1416	qe_port->rx_nrfifos = RX_NUM_FIFO;
1417	qe_port->rx_fifosize = RX_BUF_SIZE;
1418
1419	qe_port->wait_closing = UCC_WAIT_CLOSING;
1420	qe_port->port.fifosize = 512;
1421	qe_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
1422
1423	qe_port->us_info.ucc_num = qe_port->ucc_num;
1424	qe_port->us_info.regs = (phys_addr_t) res.start;
1425	qe_port->us_info.irq = qe_port->port.irq;
1426
1427	qe_port->us_info.rx_bd_ring_len = qe_port->rx_nrfifos;
1428	qe_port->us_info.tx_bd_ring_len = qe_port->tx_nrfifos;
1429
1430	/* Make sure ucc_slow_init() initializes both TX and RX */
1431	qe_port->us_info.init_tx = 1;
1432	qe_port->us_info.init_rx = 1;
1433
1434	/* Add the port to the uart sub-system.  This will cause
1435	 * qe_uart_config_port() to be called, so the us_info structure must
1436	 * be initialized.
1437	 */
1438	ret = uart_add_one_port(&ucc_uart_driver, &qe_port->port);
1439	if (ret) {
1440		dev_err(&ofdev->dev, "could not add /dev/ttyQE%u\n",
1441		       qe_port->port.line);
1442		goto out_np;
1443	}
1444
1445	platform_set_drvdata(ofdev, qe_port);
1446
1447	dev_info(&ofdev->dev, "UCC%u assigned to /dev/ttyQE%u\n",
1448		qe_port->ucc_num + 1, qe_port->port.line);
1449
1450	/* Display the mknod command for this device */
1451	dev_dbg(&ofdev->dev, "mknod command is 'mknod /dev/ttyQE%u c %u %u'\n",
1452	       qe_port->port.line, SERIAL_QE_MAJOR,
1453	       SERIAL_QE_MINOR + qe_port->port.line);
1454
1455	return 0;
1456out_np:
1457	of_node_put(np);
1458out_free:
1459	kfree(qe_port);
1460	return ret;
1461}
1462
1463static int ucc_uart_remove(struct platform_device *ofdev)
1464{
1465	struct uart_qe_port *qe_port = platform_get_drvdata(ofdev);
1466
1467	dev_info(&ofdev->dev, "removing /dev/ttyQE%u\n", qe_port->port.line);
1468
1469	uart_remove_one_port(&ucc_uart_driver, &qe_port->port);
1470
1471	kfree(qe_port);
1472
1473	return 0;
1474}
1475
1476static const struct of_device_id ucc_uart_match[] = {
1477	{
1478		.type = "serial",
1479		.compatible = "ucc_uart",
1480	},
1481	{
1482		.compatible = "fsl,t1040-ucc-uart",
1483	},
1484	{},
1485};
1486MODULE_DEVICE_TABLE(of, ucc_uart_match);
1487
1488static struct platform_driver ucc_uart_of_driver = {
1489	.driver = {
1490		.name = "ucc_uart",
1491		.of_match_table    = ucc_uart_match,
1492	},
1493	.probe  	= ucc_uart_probe,
1494	.remove 	= ucc_uart_remove,
1495};
1496
1497static int __init ucc_uart_init(void)
1498{
1499	int ret;
1500
1501	printk(KERN_INFO "Freescale QUICC Engine UART device driver\n");
1502#ifdef LOOPBACK
1503	printk(KERN_INFO "ucc-uart: Using loopback mode\n");
1504#endif
1505
1506	ret = uart_register_driver(&ucc_uart_driver);
1507	if (ret) {
1508		printk(KERN_ERR "ucc-uart: could not register UART driver\n");
1509		return ret;
1510	}
1511
1512	ret = platform_driver_register(&ucc_uart_of_driver);
1513	if (ret) {
1514		printk(KERN_ERR
1515		       "ucc-uart: could not register platform driver\n");
1516		uart_unregister_driver(&ucc_uart_driver);
1517	}
1518
1519	return ret;
1520}
1521
1522static void __exit ucc_uart_exit(void)
1523{
1524	printk(KERN_INFO
1525	       "Freescale QUICC Engine UART device driver unloading\n");
1526
1527	platform_driver_unregister(&ucc_uart_of_driver);
1528	uart_unregister_driver(&ucc_uart_driver);
1529}
1530
1531module_init(ucc_uart_init);
1532module_exit(ucc_uart_exit);
1533
1534MODULE_DESCRIPTION("Freescale QUICC Engine (QE) UART");
1535MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
1536MODULE_LICENSE("GPL v2");
1537MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_QE_MAJOR);
1538
1539