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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6/drivers/serial/
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/slab.h>
24#include <linux/serial_core.h>
25#include <linux/io.h>
26#include <linux/of_platform.h>
27#include <linux/dma-mapping.h>
28
29#include <linux/fs_uart_pd.h>
30#include <asm/ucc_slow.h>
31
32#include <linux/firmware.h>
33#include <asm/reg.h>
34
35/*
36 * The GUMR flag for Soft UART.  This would normally be defined in qe.h,
37 * but Soft-UART is a hack and we want to keep everything related to it in
38 * this file.
39 */
40#define UCC_SLOW_GUMR_H_SUART   	0x00004000      /* Soft-UART */
41
42/*
43 * soft_uart is 1 if we need to use Soft-UART mode
44 */
45static int soft_uart;
46/*
47 * firmware_loaded is 1 if the firmware has been loaded, 0 otherwise.
48 */
49static int firmware_loaded;
50
51/* Enable this macro to configure all serial ports in internal loopback
52   mode */
53/* #define LOOPBACK */
54
55/* The major and minor device numbers are defined in
56 * http://www.lanana.org/docs/device-list/devices-2.6+.txt.  For the QE
57 * UART, we have major number 204 and minor numbers 46 - 49, which are the
58 * same as for the CPM2.  This decision was made because no Freescale part
59 * has both a CPM and a QE.
60 */
61#define SERIAL_QE_MAJOR 204
62#define SERIAL_QE_MINOR 46
63
64/* Since we only have minor numbers 46 - 49, there is a hard limit of 4 ports */
65#define UCC_MAX_UART    4
66
67/* The number of buffer descriptors for receiving characters. */
68#define RX_NUM_FIFO     4
69
70/* The number of buffer descriptors for transmitting characters. */
71#define TX_NUM_FIFO     4
72
73/* The maximum size of the character buffer for a single RX BD. */
74#define RX_BUF_SIZE     32
75
76/* The maximum size of the character buffer for a single TX BD. */
77#define TX_BUF_SIZE     32
78
79/*
80 * The number of jiffies to wait after receiving a close command before the
81 * device is actually closed.  This allows the last few characters to be
82 * sent over the wire.
83 */
84#define UCC_WAIT_CLOSING 100
85
86struct ucc_uart_pram {
87	struct ucc_slow_pram common;
88	u8 res1[8];     	/* reserved */
89	__be16 maxidl;  	/* Maximum idle chars */
90	__be16 idlc;    	/* temp idle counter */
91	__be16 brkcr;   	/* Break count register */
92	__be16 parec;   	/* receive parity error counter */
93	__be16 frmec;   	/* receive framing error counter */
94	__be16 nosec;   	/* receive noise counter */
95	__be16 brkec;   	/* receive break condition counter */
96	__be16 brkln;   	/* last received break length */
97	__be16 uaddr[2];	/* UART address character 1 & 2 */
98	__be16 rtemp;   	/* Temp storage */
99	__be16 toseq;   	/* Transmit out of sequence char */
100	__be16 cchars[8];       /* control characters 1-8 */
101	__be16 rccm;    	/* receive control character mask */
102	__be16 rccr;    	/* receive control character register */
103	__be16 rlbc;    	/* receive last break character */
104	__be16 res2;    	/* reserved */
105	__be32 res3;    	/* reserved, should be cleared */
106	u8 res4;		/* reserved, should be cleared */
107	u8 res5[3];     	/* reserved, should be cleared */
108	__be32 res6;    	/* reserved, should be cleared */
109	__be32 res7;    	/* reserved, should be cleared */
110	__be32 res8;    	/* reserved, should be cleared */
111	__be32 res9;    	/* reserved, should be cleared */
112	__be32 res10;   	/* reserved, should be cleared */
113	__be32 res11;   	/* reserved, should be cleared */
114	__be32 res12;   	/* reserved, should be cleared */
115	__be32 res13;   	/* reserved, should be cleared */
116/* The rest is for Soft-UART only */
117	__be16 supsmr;  	/* 0x90, Shadow UPSMR */
118	__be16 res92;   	/* 0x92, reserved, initialize to 0 */
119	__be32 rx_state;	/* 0x94, RX state, initialize to 0 */
120	__be32 rx_cnt;  	/* 0x98, RX count, initialize to 0 */
121	u8 rx_length;   	/* 0x9C, Char length, set to 1+CL+PEN+1+SL */
122	u8 rx_bitmark;  	/* 0x9D, reserved, initialize to 0 */
123	u8 rx_temp_dlst_qe;     /* 0x9E, reserved, initialize to 0 */
124	u8 res14[0xBC - 0x9F];  /* reserved */
125	__be32 dump_ptr;	/* 0xBC, Dump pointer */
126	__be32 rx_frame_rem;    /* 0xC0, reserved, initialize to 0 */
127	u8 rx_frame_rem_size;   /* 0xC4, reserved, initialize to 0 */
128	u8 tx_mode;     	/* 0xC5, mode, 0=AHDLC, 1=UART */
129	__be16 tx_state;	/* 0xC6, TX state */
130	u8 res15[0xD0 - 0xC8];  /* reserved */
131	__be32 resD0;   	/* 0xD0, reserved, initialize to 0 */
132	u8 resD4;       	/* 0xD4, reserved, initialize to 0 */
133	__be16 resD5;   	/* 0xD5, reserved, initialize to 0 */
134} __attribute__ ((packed));
135
136/* SUPSMR definitions, for Soft-UART only */
137#define UCC_UART_SUPSMR_SL      	0x8000
138#define UCC_UART_SUPSMR_RPM_MASK	0x6000
139#define UCC_UART_SUPSMR_RPM_ODD 	0x0000
140#define UCC_UART_SUPSMR_RPM_LOW 	0x2000
141#define UCC_UART_SUPSMR_RPM_EVEN	0x4000
142#define UCC_UART_SUPSMR_RPM_HIGH	0x6000
143#define UCC_UART_SUPSMR_PEN     	0x1000
144#define UCC_UART_SUPSMR_TPM_MASK	0x0C00
145#define UCC_UART_SUPSMR_TPM_ODD 	0x0000
146#define UCC_UART_SUPSMR_TPM_LOW 	0x0400
147#define UCC_UART_SUPSMR_TPM_EVEN	0x0800
148#define UCC_UART_SUPSMR_TPM_HIGH	0x0C00
149#define UCC_UART_SUPSMR_FRZ     	0x0100
150#define UCC_UART_SUPSMR_UM_MASK 	0x00c0
151#define UCC_UART_SUPSMR_UM_NORMAL       0x0000
152#define UCC_UART_SUPSMR_UM_MAN_MULTI    0x0040
153#define UCC_UART_SUPSMR_UM_AUTO_MULTI   0x00c0
154#define UCC_UART_SUPSMR_CL_MASK 	0x0030
155#define UCC_UART_SUPSMR_CL_8    	0x0030
156#define UCC_UART_SUPSMR_CL_7    	0x0020
157#define UCC_UART_SUPSMR_CL_6    	0x0010
158#define UCC_UART_SUPSMR_CL_5    	0x0000
159
160#define UCC_UART_TX_STATE_AHDLC 	0x00
161#define UCC_UART_TX_STATE_UART  	0x01
162#define UCC_UART_TX_STATE_X1    	0x00
163#define UCC_UART_TX_STATE_X16   	0x80
164
165#define UCC_UART_PRAM_ALIGNMENT 0x100
166
167#define UCC_UART_SIZE_OF_BD     UCC_SLOW_SIZE_OF_BD
168#define NUM_CONTROL_CHARS       8
169
170/* Private per-port data structure */
171struct uart_qe_port {
172	struct uart_port port;
173	struct ucc_slow __iomem *uccp;
174	struct ucc_uart_pram __iomem *uccup;
175	struct ucc_slow_info us_info;
176	struct ucc_slow_private *us_private;
177	struct device_node *np;
178	unsigned int ucc_num;   /* First ucc is 0, not 1 */
179
180	u16 rx_nrfifos;
181	u16 rx_fifosize;
182	u16 tx_nrfifos;
183	u16 tx_fifosize;
184	int wait_closing;
185	u32 flags;
186	struct qe_bd *rx_bd_base;
187	struct qe_bd *rx_cur;
188	struct qe_bd *tx_bd_base;
189	struct qe_bd *tx_cur;
190	unsigned char *tx_buf;
191	unsigned char *rx_buf;
192	void *bd_virt;  	/* virtual address of the BD buffers */
193	dma_addr_t bd_dma_addr; /* bus address of the BD buffers */
194	unsigned int bd_size;   /* size of BD buffer space */
195};
196
197static struct uart_driver ucc_uart_driver = {
198	.owner  	= THIS_MODULE,
199	.driver_name    = "ucc_uart",
200	.dev_name       = "ttyQE",
201	.major  	= SERIAL_QE_MAJOR,
202	.minor  	= SERIAL_QE_MINOR,
203	.nr     	= UCC_MAX_UART,
204};
205
206/*
207 * Virtual to physical address translation.
208 *
209 * Given the virtual address for a character buffer, this function returns
210 * the physical (DMA) equivalent.
211 */
212static inline dma_addr_t cpu2qe_addr(void *addr, struct uart_qe_port *qe_port)
213{
214	if (likely((addr >= qe_port->bd_virt)) &&
215	    (addr < (qe_port->bd_virt + qe_port->bd_size)))
216		return qe_port->bd_dma_addr + (addr - qe_port->bd_virt);
217
218	/* something nasty happened */
219	printk(KERN_ERR "%s: addr=%p\n", __func__, addr);
220	BUG();
221	return 0;
222}
223
224/*
225 * Physical to virtual address translation.
226 *
227 * Given the physical (DMA) address for a character buffer, this function
228 * returns the virtual equivalent.
229 */
230static inline void *qe2cpu_addr(dma_addr_t addr, struct uart_qe_port *qe_port)
231{
232	/* sanity check */
233	if (likely((addr >= qe_port->bd_dma_addr) &&
234		   (addr < (qe_port->bd_dma_addr + qe_port->bd_size))))
235		return qe_port->bd_virt + (addr - qe_port->bd_dma_addr);
236
237	/* something nasty happened */
238	printk(KERN_ERR "%s: addr=%x\n", __func__, addr);
239	BUG();
240	return NULL;
241}
242
243/*
244 * Return 1 if the QE is done transmitting all buffers for this port
245 *
246 * This function scans each BD in sequence.  If we find a BD that is not
247 * ready (READY=1), then we return 0 indicating that the QE is still sending
248 * data.  If we reach the last BD (WRAP=1), then we know we've scanned
249 * the entire list, and all BDs are done.
250 */
251static unsigned int qe_uart_tx_empty(struct uart_port *port)
252{
253	struct uart_qe_port *qe_port =
254		container_of(port, struct uart_qe_port, port);
255	struct qe_bd *bdp = qe_port->tx_bd_base;
256
257	while (1) {
258		if (in_be16(&bdp->status) & BD_SC_READY)
259			/* This BD is not done, so return "not done" */
260			return 0;
261
262		if (in_be16(&bdp->status) & BD_SC_WRAP)
263			/*
264			 * This BD is done and it's the last one, so return
265			 * "done"
266			 */
267			return 1;
268
269		bdp++;
270	};
271}
272
273/*
274 * Set the modem control lines
275 *
276 * Although the QE can control the modem control lines (e.g. CTS), we
277 * don't need that support. This function must exist, however, otherwise
278 * the kernel will panic.
279 */
280void qe_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
281{
282}
283
284/*
285 * Get the current modem control line status
286 *
287 * Although the QE can control the modem control lines (e.g. CTS), this
288 * driver currently doesn't support that, so we always return Carrier
289 * Detect, Data Set Ready, and Clear To Send.
290 */
291static unsigned int qe_uart_get_mctrl(struct uart_port *port)
292{
293	return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
294}
295
296/*
297 * Disable the transmit interrupt.
298 *
299 * Although this function is called "stop_tx", it does not actually stop
300 * transmission of data.  Instead, it tells the QE to not generate an
301 * interrupt when the UCC is finished sending characters.
302 */
303static void qe_uart_stop_tx(struct uart_port *port)
304{
305	struct uart_qe_port *qe_port =
306		container_of(port, struct uart_qe_port, port);
307
308	clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
309}
310
311/*
312 * Transmit as many characters to the HW as possible.
313 *
314 * This function will attempt to stuff of all the characters from the
315 * kernel's transmit buffer into TX BDs.
316 *
317 * A return value of non-zero indicates that it successfully stuffed all
318 * characters from the kernel buffer.
319 *
320 * A return value of zero indicates that there are still characters in the
321 * kernel's buffer that have not been transmitted, but there are no more BDs
322 * available.  This function should be called again after a BD has been made
323 * available.
324 */
325static int qe_uart_tx_pump(struct uart_qe_port *qe_port)
326{
327	struct qe_bd *bdp;
328	unsigned char *p;
329	unsigned int count;
330	struct uart_port *port = &qe_port->port;
331	struct circ_buf *xmit = &port->state->xmit;
332
333	bdp = qe_port->rx_cur;
334
335	/* Handle xon/xoff */
336	if (port->x_char) {
337		/* Pick next descriptor and fill from buffer */
338		bdp = qe_port->tx_cur;
339
340		p = qe2cpu_addr(bdp->buf, qe_port);
341
342		*p++ = port->x_char;
343		out_be16(&bdp->length, 1);
344		setbits16(&bdp->status, BD_SC_READY);
345		/* Get next BD. */
346		if (in_be16(&bdp->status) & BD_SC_WRAP)
347			bdp = qe_port->tx_bd_base;
348		else
349			bdp++;
350		qe_port->tx_cur = bdp;
351
352		port->icount.tx++;
353		port->x_char = 0;
354		return 1;
355	}
356
357	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
358		qe_uart_stop_tx(port);
359		return 0;
360	}
361
362	/* Pick next descriptor and fill from buffer */
363	bdp = qe_port->tx_cur;
364
365	while (!(in_be16(&bdp->status) & BD_SC_READY) &&
366	       (xmit->tail != xmit->head)) {
367		count = 0;
368		p = qe2cpu_addr(bdp->buf, qe_port);
369		while (count < qe_port->tx_fifosize) {
370			*p++ = xmit->buf[xmit->tail];
371			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
372			port->icount.tx++;
373			count++;
374			if (xmit->head == xmit->tail)
375				break;
376		}
377
378		out_be16(&bdp->length, count);
379		setbits16(&bdp->status, BD_SC_READY);
380
381		/* Get next BD. */
382		if (in_be16(&bdp->status) & BD_SC_WRAP)
383			bdp = qe_port->tx_bd_base;
384		else
385			bdp++;
386	}
387	qe_port->tx_cur = bdp;
388
389	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
390		uart_write_wakeup(port);
391
392	if (uart_circ_empty(xmit)) {
393		/* The kernel buffer is empty, so turn off TX interrupts.  We
394		   don't need to be told when the QE is finished transmitting
395		   the data. */
396		qe_uart_stop_tx(port);
397		return 0;
398	}
399
400	return 1;
401}
402
403/*
404 * Start transmitting data
405 *
406 * This function will start transmitting any available data, if the port
407 * isn't already transmitting data.
408 */
409static void qe_uart_start_tx(struct uart_port *port)
410{
411	struct uart_qe_port *qe_port =
412		container_of(port, struct uart_qe_port, port);
413
414	/* If we currently are transmitting, then just return */
415	if (in_be16(&qe_port->uccp->uccm) & UCC_UART_UCCE_TX)
416		return;
417
418	/* Otherwise, pump the port and start transmission */
419	if (qe_uart_tx_pump(qe_port))
420		setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
421}
422
423/*
424 * Stop transmitting data
425 */
426static void qe_uart_stop_rx(struct uart_port *port)
427{
428	struct uart_qe_port *qe_port =
429		container_of(port, struct uart_qe_port, port);
430
431	clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
432}
433
434/*
435 * Enable status change interrupts
436 *
437 * We don't support status change interrupts, but we need to define this
438 * function otherwise the kernel will panic.
439 */
440static void qe_uart_enable_ms(struct uart_port *port)
441{
442}
443
444/* Start or stop sending  break signal
445 *
446 * This function controls the sending of a break signal.  If break_state=1,
447 * then we start sending a break signal.  If break_state=0, then we stop
448 * sending the break signal.
449 */
450static void qe_uart_break_ctl(struct uart_port *port, int break_state)
451{
452	struct uart_qe_port *qe_port =
453		container_of(port, struct uart_qe_port, port);
454
455	if (break_state)
456		ucc_slow_stop_tx(qe_port->us_private);
457	else
458		ucc_slow_restart_tx(qe_port->us_private);
459}
460
461/* ISR helper function for receiving character.
462 *
463 * This function is called by the ISR to handling receiving characters
464 */
465static void qe_uart_int_rx(struct uart_qe_port *qe_port)
466{
467	int i;
468	unsigned char ch, *cp;
469	struct uart_port *port = &qe_port->port;
470	struct tty_struct *tty = port->state->port.tty;
471	struct qe_bd *bdp;
472	u16 status;
473	unsigned int flg;
474
475	/* Just loop through the closed BDs and copy the characters into
476	 * the buffer.
477	 */
478	bdp = qe_port->rx_cur;
479	while (1) {
480		status = in_be16(&bdp->status);
481
482		/* If this one is empty, then we assume we've read them all */
483		if (status & BD_SC_EMPTY)
484			break;
485
486		/* get number of characters, and check space in RX buffer */
487		i = in_be16(&bdp->length);
488
489		/* If we don't have enough room in RX buffer for the entire BD,
490		 * then we try later, which will be the next RX interrupt.
491		 */
492		if (tty_buffer_request_room(tty, i) < i) {
493			dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n");
494			return;
495		}
496
497		/* get pointer */
498		cp = qe2cpu_addr(bdp->buf, qe_port);
499
500		/* loop through the buffer */
501		while (i-- > 0) {
502			ch = *cp++;
503			port->icount.rx++;
504			flg = TTY_NORMAL;
505
506			if (!i && status &
507			    (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
508				goto handle_error;
509			if (uart_handle_sysrq_char(port, ch))
510				continue;
511
512error_return:
513			tty_insert_flip_char(tty, ch, flg);
514
515		}
516
517		/* This BD is ready to be used again. Clear status. get next */
518		clrsetbits_be16(&bdp->status, BD_SC_BR | BD_SC_FR | BD_SC_PR |
519			BD_SC_OV | BD_SC_ID, BD_SC_EMPTY);
520		if (in_be16(&bdp->status) & BD_SC_WRAP)
521			bdp = qe_port->rx_bd_base;
522		else
523			bdp++;
524
525	}
526
527	/* Write back buffer pointer */
528	qe_port->rx_cur = bdp;
529
530	/* Activate BH processing */
531	tty_flip_buffer_push(tty);
532
533	return;
534
535	/* Error processing */
536
537handle_error:
538	/* Statistics */
539	if (status & BD_SC_BR)
540		port->icount.brk++;
541	if (status & BD_SC_PR)
542		port->icount.parity++;
543	if (status & BD_SC_FR)
544		port->icount.frame++;
545	if (status & BD_SC_OV)
546		port->icount.overrun++;
547
548	/* Mask out ignored conditions */
549	status &= port->read_status_mask;
550
551	/* Handle the remaining ones */
552	if (status & BD_SC_BR)
553		flg = TTY_BREAK;
554	else if (status & BD_SC_PR)
555		flg = TTY_PARITY;
556	else if (status & BD_SC_FR)
557		flg = TTY_FRAME;
558
559	/* Overrun does not affect the current character ! */
560	if (status & BD_SC_OV)
561		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
562#ifdef SUPPORT_SYSRQ
563	port->sysrq = 0;
564#endif
565	goto error_return;
566}
567
568/* Interrupt handler
569 *
570 * This interrupt handler is called after a BD is processed.
571 */
572static irqreturn_t qe_uart_int(int irq, void *data)
573{
574	struct uart_qe_port *qe_port = (struct uart_qe_port *) data;
575	struct ucc_slow __iomem *uccp = qe_port->uccp;
576	u16 events;
577
578	/* Clear the interrupts */
579	events = in_be16(&uccp->ucce);
580	out_be16(&uccp->ucce, events);
581
582	if (events & UCC_UART_UCCE_BRKE)
583		uart_handle_break(&qe_port->port);
584
585	if (events & UCC_UART_UCCE_RX)
586		qe_uart_int_rx(qe_port);
587
588	if (events & UCC_UART_UCCE_TX)
589		qe_uart_tx_pump(qe_port);
590
591	return events ? IRQ_HANDLED : IRQ_NONE;
592}
593
594/* Initialize buffer descriptors
595 *
596 * This function initializes all of the RX and TX buffer descriptors.
597 */
598static void qe_uart_initbd(struct uart_qe_port *qe_port)
599{
600	int i;
601	void *bd_virt;
602	struct qe_bd *bdp;
603
604	/* Set the physical address of the host memory buffers in the buffer
605	 * descriptors, and the virtual address for us to work with.
606	 */
607	bd_virt = qe_port->bd_virt;
608	bdp = qe_port->rx_bd_base;
609	qe_port->rx_cur = qe_port->rx_bd_base;
610	for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) {
611		out_be16(&bdp->status, BD_SC_EMPTY | BD_SC_INTRPT);
612		out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
613		out_be16(&bdp->length, 0);
614		bd_virt += qe_port->rx_fifosize;
615		bdp++;
616	}
617
618	/* */
619	out_be16(&bdp->status, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
620	out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
621	out_be16(&bdp->length, 0);
622
623	/* Set the physical address of the host memory
624	 * buffers in the buffer descriptors, and the
625	 * virtual address for us to work with.
626	 */
627	bd_virt = qe_port->bd_virt +
628		L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
629	qe_port->tx_cur = qe_port->tx_bd_base;
630	bdp = qe_port->tx_bd_base;
631	for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) {
632		out_be16(&bdp->status, BD_SC_INTRPT);
633		out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
634		out_be16(&bdp->length, 0);
635		bd_virt += qe_port->tx_fifosize;
636		bdp++;
637	}
638
639	/* Loopback requires the preamble bit to be set on the first TX BD */
640#ifdef LOOPBACK
641	setbits16(&qe_port->tx_cur->status, BD_SC_P);
642#endif
643
644	out_be16(&bdp->status, BD_SC_WRAP | BD_SC_INTRPT);
645	out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
646	out_be16(&bdp->length, 0);
647}
648
649/*
650 * Initialize a UCC for UART.
651 *
652 * This function configures a given UCC to be used as a UART device. Basic
653 * UCC initialization is handled in qe_uart_request_port().  This function
654 * does all the UART-specific stuff.
655 */
656static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
657{
658	u32 cecr_subblock;
659	struct ucc_slow __iomem *uccp = qe_port->uccp;
660	struct ucc_uart_pram *uccup = qe_port->uccup;
661
662	unsigned int i;
663
664	/* First, disable TX and RX in the UCC */
665	ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
666
667	/* Program the UCC UART parameter RAM */
668	out_8(&uccup->common.rbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
669	out_8(&uccup->common.tbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
670	out_be16(&uccup->common.mrblr, qe_port->rx_fifosize);
671	out_be16(&uccup->maxidl, 0x10);
672	out_be16(&uccup->brkcr, 1);
673	out_be16(&uccup->parec, 0);
674	out_be16(&uccup->frmec, 0);
675	out_be16(&uccup->nosec, 0);
676	out_be16(&uccup->brkec, 0);
677	out_be16(&uccup->uaddr[0], 0);
678	out_be16(&uccup->uaddr[1], 0);
679	out_be16(&uccup->toseq, 0);
680	for (i = 0; i < 8; i++)
681		out_be16(&uccup->cchars[i], 0xC000);
682	out_be16(&uccup->rccm, 0xc0ff);
683
684	/* Configure the GUMR registers for UART */
685	if (soft_uart) {
686		/* Soft-UART requires a 1X multiplier for TX */
687		clrsetbits_be32(&uccp->gumr_l,
688			UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
689			UCC_SLOW_GUMR_L_RDCR_MASK,
690			UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 |
691			UCC_SLOW_GUMR_L_RDCR_16);
692
693		clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
694			UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
695	} else {
696		clrsetbits_be32(&uccp->gumr_l,
697			UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
698			UCC_SLOW_GUMR_L_RDCR_MASK,
699			UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 |
700			UCC_SLOW_GUMR_L_RDCR_16);
701
702		clrsetbits_be32(&uccp->gumr_h,
703			UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX,
704			UCC_SLOW_GUMR_H_RFW);
705	}
706
707#ifdef LOOPBACK
708	clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
709		UCC_SLOW_GUMR_L_DIAG_LOOP);
710	clrsetbits_be32(&uccp->gumr_h,
711		UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN,
712		UCC_SLOW_GUMR_H_CDS);
713#endif
714
715	/* Disable rx interrupts  and clear all pending events.  */
716	out_be16(&uccp->uccm, 0);
717	out_be16(&uccp->ucce, 0xffff);
718	out_be16(&uccp->udsr, 0x7e7e);
719
720	/* Initialize UPSMR */
721	out_be16(&uccp->upsmr, 0);
722
723	if (soft_uart) {
724		out_be16(&uccup->supsmr, 0x30);
725		out_be16(&uccup->res92, 0);
726		out_be32(&uccup->rx_state, 0);
727		out_be32(&uccup->rx_cnt, 0);
728		out_8(&uccup->rx_bitmark, 0);
729		out_8(&uccup->rx_length, 10);
730		out_be32(&uccup->dump_ptr, 0x4000);
731		out_8(&uccup->rx_temp_dlst_qe, 0);
732		out_be32(&uccup->rx_frame_rem, 0);
733		out_8(&uccup->rx_frame_rem_size, 0);
734		/* Soft-UART requires TX to be 1X */
735		out_8(&uccup->tx_mode,
736			UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1);
737		out_be16(&uccup->tx_state, 0);
738		out_8(&uccup->resD4, 0);
739		out_be16(&uccup->resD5, 0);
740
741		/* Set UART mode.
742		 * Enable receive and transmit.
743		 */
744
745		/* From the microcode errata:
746		 * 1.GUMR_L register, set mode=0010 (QMC).
747		 * 2.Set GUMR_H[17] bit. (UART/AHDLC mode).
748		 * 3.Set GUMR_H[19:20] (Transparent mode)
749		 * 4.Clear GUMR_H[26] (RFW)
750		 * ...
751		 * 6.Receiver must use 16x over sampling
752		 */
753		clrsetbits_be32(&uccp->gumr_l,
754			UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
755			UCC_SLOW_GUMR_L_RDCR_MASK,
756			UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 |
757			UCC_SLOW_GUMR_L_RDCR_16);
758
759		clrsetbits_be32(&uccp->gumr_h,
760			UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN,
761			UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX |
762			UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL);
763
764#ifdef LOOPBACK
765		clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
766				UCC_SLOW_GUMR_L_DIAG_LOOP);
767		clrbits32(&uccp->gumr_h, UCC_SLOW_GUMR_H_CTSP |
768			  UCC_SLOW_GUMR_H_CDS);
769#endif
770
771		cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
772		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
773			QE_CR_PROTOCOL_UNSPECIFIED, 0);
774	} else {
775		cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
776		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
777			QE_CR_PROTOCOL_UART, 0);
778	}
779}
780
781/*
782 * Initialize the port.
783 */
784static int qe_uart_startup(struct uart_port *port)
785{
786	struct uart_qe_port *qe_port =
787		container_of(port, struct uart_qe_port, port);
788	int ret;
789
790	/*
791	 * If we're using Soft-UART mode, then we need to make sure the
792	 * firmware has been uploaded first.
793	 */
794	if (soft_uart && !firmware_loaded) {
795		dev_err(port->dev, "Soft-UART firmware not uploaded\n");
796		return -ENODEV;
797	}
798
799	qe_uart_initbd(qe_port);
800	qe_uart_init_ucc(qe_port);
801
802	/* Install interrupt handler. */
803	ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart",
804		qe_port);
805	if (ret) {
806		dev_err(port->dev, "could not claim IRQ %u\n", port->irq);
807		return ret;
808	}
809
810	/* Startup rx-int */
811	setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
812	ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX);
813
814	return 0;
815}
816
817/*
818 * Shutdown the port.
819 */
820static void qe_uart_shutdown(struct uart_port *port)
821{
822	struct uart_qe_port *qe_port =
823		container_of(port, struct uart_qe_port, port);
824	struct ucc_slow __iomem *uccp = qe_port->uccp;
825	unsigned int timeout = 20;
826
827	/* Disable RX and TX */
828
829	/* Wait for all the BDs marked sent */
830	while (!qe_uart_tx_empty(port)) {
831		if (!--timeout) {
832			dev_warn(port->dev, "shutdown timeout\n");
833			break;
834		}
835		set_current_state(TASK_UNINTERRUPTIBLE);
836		schedule_timeout(2);
837	}
838
839	if (qe_port->wait_closing) {
840		/* Wait a bit longer */
841		set_current_state(TASK_UNINTERRUPTIBLE);
842		schedule_timeout(qe_port->wait_closing);
843	}
844
845	/* Stop uarts */
846	ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
847	clrbits16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX);
848
849	/* Shut them really down and reinit buffer descriptors */
850	ucc_slow_graceful_stop_tx(qe_port->us_private);
851	qe_uart_initbd(qe_port);
852
853	free_irq(port->irq, qe_port);
854}
855
856/*
857 * Set the serial port parameters.
858 */
859static void qe_uart_set_termios(struct uart_port *port,
860				struct ktermios *termios, struct ktermios *old)
861{
862	struct uart_qe_port *qe_port =
863		container_of(port, struct uart_qe_port, port);
864	struct ucc_slow __iomem *uccp = qe_port->uccp;
865	unsigned int baud;
866	unsigned long flags;
867	u16 upsmr = in_be16(&uccp->upsmr);
868	struct ucc_uart_pram __iomem *uccup = qe_port->uccup;
869	u16 supsmr = in_be16(&uccup->supsmr);
870	u8 char_length = 2; /* 1 + CL + PEN + 1 + SL */
871
872	/* Character length programmed into the mode register is the
873	 * sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
874	 * 1 or 2 stop bits, minus 1.
875	 * The value 'bits' counts this for us.
876	 */
877
878	/* byte size */
879	upsmr &= UCC_UART_UPSMR_CL_MASK;
880	supsmr &= UCC_UART_SUPSMR_CL_MASK;
881
882	switch (termios->c_cflag & CSIZE) {
883	case CS5:
884		upsmr |= UCC_UART_UPSMR_CL_5;
885		supsmr |= UCC_UART_SUPSMR_CL_5;
886		char_length += 5;
887		break;
888	case CS6:
889		upsmr |= UCC_UART_UPSMR_CL_6;
890		supsmr |= UCC_UART_SUPSMR_CL_6;
891		char_length += 6;
892		break;
893	case CS7:
894		upsmr |= UCC_UART_UPSMR_CL_7;
895		supsmr |= UCC_UART_SUPSMR_CL_7;
896		char_length += 7;
897		break;
898	default:	/* case CS8 */
899		upsmr |= UCC_UART_UPSMR_CL_8;
900		supsmr |= UCC_UART_SUPSMR_CL_8;
901		char_length += 8;
902		break;
903	}
904
905	/* If CSTOPB is set, we want two stop bits */
906	if (termios->c_cflag & CSTOPB) {
907		upsmr |= UCC_UART_UPSMR_SL;
908		supsmr |= UCC_UART_SUPSMR_SL;
909		char_length++;  /* + SL */
910	}
911
912	if (termios->c_cflag & PARENB) {
913		upsmr |= UCC_UART_UPSMR_PEN;
914		supsmr |= UCC_UART_SUPSMR_PEN;
915		char_length++;  /* + PEN */
916
917		if (!(termios->c_cflag & PARODD)) {
918			upsmr &= ~(UCC_UART_UPSMR_RPM_MASK |
919				   UCC_UART_UPSMR_TPM_MASK);
920			upsmr |= UCC_UART_UPSMR_RPM_EVEN |
921				UCC_UART_UPSMR_TPM_EVEN;
922			supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK |
923				    UCC_UART_SUPSMR_TPM_MASK);
924			supsmr |= UCC_UART_SUPSMR_RPM_EVEN |
925				UCC_UART_SUPSMR_TPM_EVEN;
926		}
927	}
928
929	/*
930	 * Set up parity check flag
931	 */
932	port->read_status_mask = BD_SC_EMPTY | BD_SC_OV;
933	if (termios->c_iflag & INPCK)
934		port->read_status_mask |= BD_SC_FR | BD_SC_PR;
935	if (termios->c_iflag & (BRKINT | PARMRK))
936		port->read_status_mask |= BD_SC_BR;
937
938	/*
939	 * Characters to ignore
940	 */
941	port->ignore_status_mask = 0;
942	if (termios->c_iflag & IGNPAR)
943		port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
944	if (termios->c_iflag & IGNBRK) {
945		port->ignore_status_mask |= BD_SC_BR;
946		/*
947		 * If we're ignore parity and break indicators, ignore
948		 * overruns too.  (For real raw support).
949		 */
950		if (termios->c_iflag & IGNPAR)
951			port->ignore_status_mask |= BD_SC_OV;
952	}
953	/*
954	 * !!! ignore all characters if CREAD is not set
955	 */
956	if ((termios->c_cflag & CREAD) == 0)
957		port->read_status_mask &= ~BD_SC_EMPTY;
958
959	baud = uart_get_baud_rate(port, termios, old, 0, 115200);
960
961	/* Do we really need a spinlock here? */
962	spin_lock_irqsave(&port->lock, flags);
963
964	out_be16(&uccp->upsmr, upsmr);
965	if (soft_uart) {
966		out_be16(&uccup->supsmr, supsmr);
967		out_8(&uccup->rx_length, char_length);
968
969		/* Soft-UART requires a 1X multiplier for TX */
970		qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
971		qe_setbrg(qe_port->us_info.tx_clock, baud, 1);
972	} else {
973		qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
974		qe_setbrg(qe_port->us_info.tx_clock, baud, 16);
975	}
976
977	spin_unlock_irqrestore(&port->lock, flags);
978}
979
980/*
981 * Return a pointer to a string that describes what kind of port this is.
982 */
983static const char *qe_uart_type(struct uart_port *port)
984{
985	return "QE";
986}
987
988/*
989 * Allocate any memory and I/O resources required by the port.
990 */
991static int qe_uart_request_port(struct uart_port *port)
992{
993	int ret;
994	struct uart_qe_port *qe_port =
995		container_of(port, struct uart_qe_port, port);
996	struct ucc_slow_info *us_info = &qe_port->us_info;
997	struct ucc_slow_private *uccs;
998	unsigned int rx_size, tx_size;
999	void *bd_virt;
1000	dma_addr_t bd_dma_addr = 0;
1001
1002	ret = ucc_slow_init(us_info, &uccs);
1003	if (ret) {
1004		dev_err(port->dev, "could not initialize UCC%u\n",
1005		       qe_port->ucc_num);
1006		return ret;
1007	}
1008
1009	qe_port->us_private = uccs;
1010	qe_port->uccp = uccs->us_regs;
1011	qe_port->uccup = (struct ucc_uart_pram *) uccs->us_pram;
1012	qe_port->rx_bd_base = uccs->rx_bd;
1013	qe_port->tx_bd_base = uccs->tx_bd;
1014
1015	/*
1016	 * Allocate the transmit and receive data buffers.
1017	 */
1018
1019	rx_size = L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
1020	tx_size = L1_CACHE_ALIGN(qe_port->tx_nrfifos * qe_port->tx_fifosize);
1021
1022	bd_virt = dma_alloc_coherent(port->dev, rx_size + tx_size, &bd_dma_addr,
1023		GFP_KERNEL);
1024	if (!bd_virt) {
1025		dev_err(port->dev, "could not allocate buffer descriptors\n");
1026		return -ENOMEM;
1027	}
1028
1029	qe_port->bd_virt = bd_virt;
1030	qe_port->bd_dma_addr = bd_dma_addr;
1031	qe_port->bd_size = rx_size + tx_size;
1032
1033	qe_port->rx_buf = bd_virt;
1034	qe_port->tx_buf = qe_port->rx_buf + rx_size;
1035
1036	return 0;
1037}
1038
1039/*
1040 * Configure the port.
1041 *
1042 * We say we're a CPM-type port because that's mostly true.  Once the device
1043 * is configured, this driver operates almost identically to the CPM serial
1044 * driver.
1045 */
1046static void qe_uart_config_port(struct uart_port *port, int flags)
1047{
1048	if (flags & UART_CONFIG_TYPE) {
1049		port->type = PORT_CPM;
1050		qe_uart_request_port(port);
1051	}
1052}
1053
1054/*
1055 * Release any memory and I/O resources that were allocated in
1056 * qe_uart_request_port().
1057 */
1058static void qe_uart_release_port(struct uart_port *port)
1059{
1060	struct uart_qe_port *qe_port =
1061		container_of(port, struct uart_qe_port, port);
1062	struct ucc_slow_private *uccs = qe_port->us_private;
1063
1064	dma_free_coherent(port->dev, qe_port->bd_size, qe_port->bd_virt,
1065			  qe_port->bd_dma_addr);
1066
1067	ucc_slow_free(uccs);
1068}
1069
1070/*
1071 * Verify that the data in serial_struct is suitable for this device.
1072 */
1073static int qe_uart_verify_port(struct uart_port *port,
1074			       struct serial_struct *ser)
1075{
1076	if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
1077		return -EINVAL;
1078
1079	if (ser->irq < 0 || ser->irq >= nr_irqs)
1080		return -EINVAL;
1081
1082	if (ser->baud_base < 9600)
1083		return -EINVAL;
1084
1085	return 0;
1086}
1087/* UART operations
1088 *
1089 * Details on these functions can be found in Documentation/serial/driver
1090 */
1091static struct uart_ops qe_uart_pops = {
1092	.tx_empty       = qe_uart_tx_empty,
1093	.set_mctrl      = qe_uart_set_mctrl,
1094	.get_mctrl      = qe_uart_get_mctrl,
1095	.stop_tx	= qe_uart_stop_tx,
1096	.start_tx       = qe_uart_start_tx,
1097	.stop_rx	= qe_uart_stop_rx,
1098	.enable_ms      = qe_uart_enable_ms,
1099	.break_ctl      = qe_uart_break_ctl,
1100	.startup	= qe_uart_startup,
1101	.shutdown       = qe_uart_shutdown,
1102	.set_termios    = qe_uart_set_termios,
1103	.type   	= qe_uart_type,
1104	.release_port   = qe_uart_release_port,
1105	.request_port   = qe_uart_request_port,
1106	.config_port    = qe_uart_config_port,
1107	.verify_port    = qe_uart_verify_port,
1108};
1109
1110/*
1111 * Obtain the SOC model number and revision level
1112 *
1113 * This function parses the device tree to obtain the SOC model.  It then
1114 * reads the SVR register to the revision.
1115 *
1116 * The device tree stores the SOC model two different ways.
1117 *
1118 * The new way is:
1119 *
1120 *      	cpu@0 {
1121 *      		compatible = "PowerPC,8323";
1122 *      		device_type = "cpu";
1123 *      		...
1124 *
1125 *
1126 * The old way is:
1127 *      	 PowerPC,8323@0 {
1128 *      		device_type = "cpu";
1129 *      		...
1130 *
1131 * This code first checks the new way, and then the old way.
1132 */
1133static unsigned int soc_info(unsigned int *rev_h, unsigned int *rev_l)
1134{
1135	struct device_node *np;
1136	const char *soc_string;
1137	unsigned int svr;
1138	unsigned int soc;
1139
1140	/* Find the CPU node */
1141	np = of_find_node_by_type(NULL, "cpu");
1142	if (!np)
1143		return 0;
1144	/* Find the compatible property */
1145	soc_string = of_get_property(np, "compatible", NULL);
1146	if (!soc_string)
1147		/* No compatible property, so try the name. */
1148		soc_string = np->name;
1149
1150	/* Extract the SOC number from the "PowerPC," string */
1151	if ((sscanf(soc_string, "PowerPC,%u", &soc) != 1) || !soc)
1152		return 0;
1153
1154	/* Get the revision from the SVR */
1155	svr = mfspr(SPRN_SVR);
1156	*rev_h = (svr >> 4) & 0xf;
1157	*rev_l = svr & 0xf;
1158
1159	return soc;
1160}
1161
1162/*
1163 * requst_firmware_nowait() callback function
1164 *
1165 * This function is called by the kernel when a firmware is made available,
1166 * or if it times out waiting for the firmware.
1167 */
1168static void uart_firmware_cont(const struct firmware *fw, void *context)
1169{
1170	struct qe_firmware *firmware;
1171	struct device *dev = context;
1172	int ret;
1173
1174	if (!fw) {
1175		dev_err(dev, "firmware not found\n");
1176		return;
1177	}
1178
1179	firmware = (struct qe_firmware *) fw->data;
1180
1181	if (firmware->header.length != fw->size) {
1182		dev_err(dev, "invalid firmware\n");
1183		goto out;
1184	}
1185
1186	ret = qe_upload_firmware(firmware);
1187	if (ret) {
1188		dev_err(dev, "could not load firmware\n");
1189		goto out;
1190	}
1191
1192	firmware_loaded = 1;
1193 out:
1194	release_firmware(fw);
1195}
1196
1197static int ucc_uart_probe(struct platform_device *ofdev,
1198	const struct of_device_id *match)
1199{
1200	struct device_node *np = ofdev->dev.of_node;
1201	const unsigned int *iprop;      /* Integer OF properties */
1202	const char *sprop;      /* String OF properties */
1203	struct uart_qe_port *qe_port = NULL;
1204	struct resource res;
1205	int ret;
1206
1207	/*
1208	 * Determine if we need Soft-UART mode
1209	 */
1210	if (of_find_property(np, "soft-uart", NULL)) {
1211		dev_dbg(&ofdev->dev, "using Soft-UART mode\n");
1212		soft_uart = 1;
1213	}
1214
1215	/*
1216	 * If we are using Soft-UART, determine if we need to upload the
1217	 * firmware, too.
1218	 */
1219	if (soft_uart) {
1220		struct qe_firmware_info *qe_fw_info;
1221
1222		qe_fw_info = qe_get_firmware_info();
1223
1224		/* Check if the firmware has been uploaded. */
1225		if (qe_fw_info && strstr(qe_fw_info->id, "Soft-UART")) {
1226			firmware_loaded = 1;
1227		} else {
1228			char filename[32];
1229			unsigned int soc;
1230			unsigned int rev_h;
1231			unsigned int rev_l;
1232
1233			soc = soc_info(&rev_h, &rev_l);
1234			if (!soc) {
1235				dev_err(&ofdev->dev, "unknown CPU model\n");
1236				return -ENXIO;
1237			}
1238			sprintf(filename, "fsl_qe_ucode_uart_%u_%u%u.bin",
1239				soc, rev_h, rev_l);
1240
1241			dev_info(&ofdev->dev, "waiting for firmware %s\n",
1242				filename);
1243
1244			/*
1245			 * We call request_firmware_nowait instead of
1246			 * request_firmware so that the driver can load and
1247			 * initialize the ports without holding up the rest of
1248			 * the kernel.  If hotplug support is enabled in the
1249			 * kernel, then we use it.
1250			 */
1251			ret = request_firmware_nowait(THIS_MODULE,
1252				FW_ACTION_HOTPLUG, filename, &ofdev->dev,
1253				GFP_KERNEL, &ofdev->dev, uart_firmware_cont);
1254			if (ret) {
1255				dev_err(&ofdev->dev,
1256					"could not load firmware %s\n",
1257					filename);
1258				return ret;
1259			}
1260		}
1261	}
1262
1263	qe_port = kzalloc(sizeof(struct uart_qe_port), GFP_KERNEL);
1264	if (!qe_port) {
1265		dev_err(&ofdev->dev, "can't allocate QE port structure\n");
1266		return -ENOMEM;
1267	}
1268
1269	/* Search for IRQ and mapbase */
1270	ret = of_address_to_resource(np, 0, &res);
1271	if (ret) {
1272		dev_err(&ofdev->dev, "missing 'reg' property in device tree\n");
1273		kfree(qe_port);
1274		return ret;
1275	}
1276	if (!res.start) {
1277		dev_err(&ofdev->dev, "invalid 'reg' property in device tree\n");
1278		kfree(qe_port);
1279		return -EINVAL;
1280	}
1281	qe_port->port.mapbase = res.start;
1282
1283	/* Get the UCC number (device ID) */
1284	/* UCCs are numbered 1-7 */
1285	iprop = of_get_property(np, "cell-index", NULL);
1286	if (!iprop) {
1287		iprop = of_get_property(np, "device-id", NULL);
1288		if (!iprop) {
1289			kfree(qe_port);
1290			dev_err(&ofdev->dev, "UCC is unspecified in "
1291				"device tree\n");
1292			return -EINVAL;
1293		}
1294	}
1295
1296	if ((*iprop < 1) || (*iprop > UCC_MAX_NUM)) {
1297		dev_err(&ofdev->dev, "no support for UCC%u\n", *iprop);
1298		kfree(qe_port);
1299		return -ENODEV;
1300	}
1301	qe_port->ucc_num = *iprop - 1;
1302
1303	/*
1304	 * In the future, we should not require the BRG to be specified in the
1305	 * device tree.  If no clock-source is specified, then just pick a BRG
1306	 * to use.  This requires a new QE library function that manages BRG
1307	 * assignments.
1308	 */
1309
1310	sprop = of_get_property(np, "rx-clock-name", NULL);
1311	if (!sprop) {
1312		dev_err(&ofdev->dev, "missing rx-clock-name in device tree\n");
1313		kfree(qe_port);
1314		return -ENODEV;
1315	}
1316
1317	qe_port->us_info.rx_clock = qe_clock_source(sprop);
1318	if ((qe_port->us_info.rx_clock < QE_BRG1) ||
1319	    (qe_port->us_info.rx_clock > QE_BRG16)) {
1320		dev_err(&ofdev->dev, "rx-clock-name must be a BRG for UART\n");
1321		kfree(qe_port);
1322		return -ENODEV;
1323	}
1324
1325#ifdef LOOPBACK
1326	/* In internal loopback mode, TX and RX must use the same clock */
1327	qe_port->us_info.tx_clock = qe_port->us_info.rx_clock;
1328#else
1329	sprop = of_get_property(np, "tx-clock-name", NULL);
1330	if (!sprop) {
1331		dev_err(&ofdev->dev, "missing tx-clock-name in device tree\n");
1332		kfree(qe_port);
1333		return -ENODEV;
1334	}
1335	qe_port->us_info.tx_clock = qe_clock_source(sprop);
1336#endif
1337	if ((qe_port->us_info.tx_clock < QE_BRG1) ||
1338	    (qe_port->us_info.tx_clock > QE_BRG16)) {
1339		dev_err(&ofdev->dev, "tx-clock-name must be a BRG for UART\n");
1340		kfree(qe_port);
1341		return -ENODEV;
1342	}
1343
1344	/* Get the port number, numbered 0-3 */
1345	iprop = of_get_property(np, "port-number", NULL);
1346	if (!iprop) {
1347		dev_err(&ofdev->dev, "missing port-number in device tree\n");
1348		kfree(qe_port);
1349		return -EINVAL;
1350	}
1351	qe_port->port.line = *iprop;
1352	if (qe_port->port.line >= UCC_MAX_UART) {
1353		dev_err(&ofdev->dev, "port-number must be 0-%u\n",
1354			UCC_MAX_UART - 1);
1355		kfree(qe_port);
1356		return -EINVAL;
1357	}
1358
1359	qe_port->port.irq = irq_of_parse_and_map(np, 0);
1360	if (qe_port->port.irq == NO_IRQ) {
1361		dev_err(&ofdev->dev, "could not map IRQ for UCC%u\n",
1362		       qe_port->ucc_num + 1);
1363		kfree(qe_port);
1364		return -EINVAL;
1365	}
1366
1367	/*
1368	 * Newer device trees have an "fsl,qe" compatible property for the QE
1369	 * node, but we still need to support older device trees.
1370	 */
1371	np = of_find_compatible_node(NULL, NULL, "fsl,qe");
1372	if (!np) {
1373		np = of_find_node_by_type(NULL, "qe");
1374		if (!np) {
1375			dev_err(&ofdev->dev, "could not find 'qe' node\n");
1376			kfree(qe_port);
1377			return -EINVAL;
1378		}
1379	}
1380
1381	iprop = of_get_property(np, "brg-frequency", NULL);
1382	if (!iprop) {
1383		dev_err(&ofdev->dev,
1384		       "missing brg-frequency in device tree\n");
1385		kfree(qe_port);
1386		return -EINVAL;
1387	}
1388
1389	if (*iprop)
1390		qe_port->port.uartclk = *iprop;
1391	else {
1392		/*
1393		 * Older versions of U-Boot do not initialize the brg-frequency
1394		 * property, so in this case we assume the BRG frequency is
1395		 * half the QE bus frequency.
1396		 */
1397		iprop = of_get_property(np, "bus-frequency", NULL);
1398		if (!iprop) {
1399			dev_err(&ofdev->dev,
1400				"missing QE bus-frequency in device tree\n");
1401			kfree(qe_port);
1402			return -EINVAL;
1403		}
1404		if (*iprop)
1405			qe_port->port.uartclk = *iprop / 2;
1406		else {
1407			dev_err(&ofdev->dev,
1408				"invalid QE bus-frequency in device tree\n");
1409			kfree(qe_port);
1410			return -EINVAL;
1411		}
1412	}
1413
1414	spin_lock_init(&qe_port->port.lock);
1415	qe_port->np = np;
1416	qe_port->port.dev = &ofdev->dev;
1417	qe_port->port.ops = &qe_uart_pops;
1418	qe_port->port.iotype = UPIO_MEM;
1419
1420	qe_port->tx_nrfifos = TX_NUM_FIFO;
1421	qe_port->tx_fifosize = TX_BUF_SIZE;
1422	qe_port->rx_nrfifos = RX_NUM_FIFO;
1423	qe_port->rx_fifosize = RX_BUF_SIZE;
1424
1425	qe_port->wait_closing = UCC_WAIT_CLOSING;
1426	qe_port->port.fifosize = 512;
1427	qe_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
1428
1429	qe_port->us_info.ucc_num = qe_port->ucc_num;
1430	qe_port->us_info.regs = (phys_addr_t) res.start;
1431	qe_port->us_info.irq = qe_port->port.irq;
1432
1433	qe_port->us_info.rx_bd_ring_len = qe_port->rx_nrfifos;
1434	qe_port->us_info.tx_bd_ring_len = qe_port->tx_nrfifos;
1435
1436	/* Make sure ucc_slow_init() initializes both TX and RX */
1437	qe_port->us_info.init_tx = 1;
1438	qe_port->us_info.init_rx = 1;
1439
1440	/* Add the port to the uart sub-system.  This will cause
1441	 * qe_uart_config_port() to be called, so the us_info structure must
1442	 * be initialized.
1443	 */
1444	ret = uart_add_one_port(&ucc_uart_driver, &qe_port->port);
1445	if (ret) {
1446		dev_err(&ofdev->dev, "could not add /dev/ttyQE%u\n",
1447		       qe_port->port.line);
1448		kfree(qe_port);
1449		return ret;
1450	}
1451
1452	dev_set_drvdata(&ofdev->dev, qe_port);
1453
1454	dev_info(&ofdev->dev, "UCC%u assigned to /dev/ttyQE%u\n",
1455		qe_port->ucc_num + 1, qe_port->port.line);
1456
1457	/* Display the mknod command for this device */
1458	dev_dbg(&ofdev->dev, "mknod command is 'mknod /dev/ttyQE%u c %u %u'\n",
1459	       qe_port->port.line, SERIAL_QE_MAJOR,
1460	       SERIAL_QE_MINOR + qe_port->port.line);
1461
1462	return 0;
1463}
1464
1465static int ucc_uart_remove(struct platform_device *ofdev)
1466{
1467	struct uart_qe_port *qe_port = dev_get_drvdata(&ofdev->dev);
1468
1469	dev_info(&ofdev->dev, "removing /dev/ttyQE%u\n", qe_port->port.line);
1470
1471	uart_remove_one_port(&ucc_uart_driver, &qe_port->port);
1472
1473	dev_set_drvdata(&ofdev->dev, NULL);
1474	kfree(qe_port);
1475
1476	return 0;
1477}
1478
1479static struct of_device_id ucc_uart_match[] = {
1480	{
1481		.type = "serial",
1482		.compatible = "ucc_uart",
1483	},
1484	{},
1485};
1486MODULE_DEVICE_TABLE(of, ucc_uart_match);
1487
1488static struct of_platform_driver ucc_uart_of_driver = {
1489	.driver = {
1490		.name = "ucc_uart",
1491		.owner = THIS_MODULE,
1492		.of_match_table    = ucc_uart_match,
1493	},
1494	.probe  	= ucc_uart_probe,
1495	.remove 	= ucc_uart_remove,
1496};
1497
1498static int __init ucc_uart_init(void)
1499{
1500	int ret;
1501
1502	printk(KERN_INFO "Freescale QUICC Engine UART device driver\n");
1503#ifdef LOOPBACK
1504	printk(KERN_INFO "ucc-uart: Using loopback mode\n");
1505#endif
1506
1507	ret = uart_register_driver(&ucc_uart_driver);
1508	if (ret) {
1509		printk(KERN_ERR "ucc-uart: could not register UART driver\n");
1510		return ret;
1511	}
1512
1513	ret = of_register_platform_driver(&ucc_uart_of_driver);
1514	if (ret)
1515		printk(KERN_ERR
1516		       "ucc-uart: could not register platform driver\n");
1517
1518	return ret;
1519}
1520
1521static void __exit ucc_uart_exit(void)
1522{
1523	printk(KERN_INFO
1524	       "Freescale QUICC Engine UART device driver unloading\n");
1525
1526	of_unregister_platform_driver(&ucc_uart_of_driver);
1527	uart_unregister_driver(&ucc_uart_driver);
1528}
1529
1530module_init(ucc_uart_init);
1531module_exit(ucc_uart_exit);
1532
1533MODULE_DESCRIPTION("Freescale QUICC Engine (QE) UART");
1534MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
1535MODULE_LICENSE("GPL v2");
1536MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_QE_MAJOR);
1537