1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Freescale QUICC Engine UART device driver
4 *
5 * Author: Timur Tabi <timur@freescale.com>
6 *
7 * Copyright 2007 Freescale Semiconductor, Inc.
8 *
9 * This driver adds support for UART devices via Freescale's QUICC Engine
10 * found on some Freescale SOCs.
11 *
12 * If Soft-UART support is needed but not already present, then this driver
13 * will request and upload the "Soft-UART" microcode upon probe.  The
14 * filename of the microcode should be fsl_qe_ucode_uart_X_YZ.bin, where "X"
15 * is the name of the SOC (e.g. 8323), and YZ is the revision of the SOC,
16 * (e.g. "11" for 1.1).
17 */
18
19#include <linux/module.h>
20#include <linux/platform_device.h>
21#include <linux/serial.h>
22#include <linux/serial_core.h>
23#include <linux/slab.h>
24#include <linux/tty.h>
25#include <linux/tty_flip.h>
26#include <linux/io.h>
27#include <linux/of.h>
28#include <linux/of_address.h>
29#include <linux/of_irq.h>
30#include <linux/dma-mapping.h>
31
32#include <soc/fsl/qe/ucc_slow.h>
33
34#include <linux/firmware.h>
35#include <soc/fsl/cpm.h>
36
37#ifdef CONFIG_PPC32
38#include <asm/reg.h> /* mfspr, SPRN_SVR */
39#endif
40
41/*
42 * The GUMR flag for Soft UART.  This would normally be defined in qe.h,
43 * but Soft-UART is a hack and we want to keep everything related to it in
44 * this file.
45 */
46#define UCC_SLOW_GUMR_H_SUART   	0x00004000      /* Soft-UART */
47
48/*
49 * soft_uart is 1 if we need to use Soft-UART mode
50 */
51static int soft_uart;
52/*
53 * firmware_loaded is 1 if the firmware has been loaded, 0 otherwise.
54 */
55static int firmware_loaded;
56
57/* Enable this macro to configure all serial ports in internal loopback
58   mode */
59/* #define LOOPBACK */
60
61/* The major and minor device numbers are defined in
62 * Documentation/admin-guide/devices.txt.  For the QE
63 * UART, we have major number 204 and minor numbers 46 - 49, which are the
64 * same as for the CPM2.  This decision was made because no Freescale part
65 * has both a CPM and a QE.
66 */
67#define SERIAL_QE_MAJOR 204
68#define SERIAL_QE_MINOR 46
69
70/* Since we only have minor numbers 46 - 49, there is a hard limit of 4 ports */
71#define UCC_MAX_UART    4
72
73/* The number of buffer descriptors for receiving characters. */
74#define RX_NUM_FIFO     4
75
76/* The number of buffer descriptors for transmitting characters. */
77#define TX_NUM_FIFO     4
78
79/* The maximum size of the character buffer for a single RX BD. */
80#define RX_BUF_SIZE     32
81
82/* The maximum size of the character buffer for a single TX BD. */
83#define TX_BUF_SIZE     32
84
85/*
86 * The number of jiffies to wait after receiving a close command before the
87 * device is actually closed.  This allows the last few characters to be
88 * sent over the wire.
89 */
90#define UCC_WAIT_CLOSING 100
91
92struct ucc_uart_pram {
93	struct ucc_slow_pram common;
94	u8 res1[8];     	/* reserved */
95	__be16 maxidl;  	/* Maximum idle chars */
96	__be16 idlc;    	/* temp idle counter */
97	__be16 brkcr;   	/* Break count register */
98	__be16 parec;   	/* receive parity error counter */
99	__be16 frmec;   	/* receive framing error counter */
100	__be16 nosec;   	/* receive noise counter */
101	__be16 brkec;   	/* receive break condition counter */
102	__be16 brkln;   	/* last received break length */
103	__be16 uaddr[2];	/* UART address character 1 & 2 */
104	__be16 rtemp;   	/* Temp storage */
105	__be16 toseq;   	/* Transmit out of sequence char */
106	__be16 cchars[8];       /* control characters 1-8 */
107	__be16 rccm;    	/* receive control character mask */
108	__be16 rccr;    	/* receive control character register */
109	__be16 rlbc;    	/* receive last break character */
110	__be16 res2;    	/* reserved */
111	__be32 res3;    	/* reserved, should be cleared */
112	u8 res4;		/* reserved, should be cleared */
113	u8 res5[3];     	/* reserved, should be cleared */
114	__be32 res6;    	/* reserved, should be cleared */
115	__be32 res7;    	/* reserved, should be cleared */
116	__be32 res8;    	/* reserved, should be cleared */
117	__be32 res9;    	/* reserved, should be cleared */
118	__be32 res10;   	/* reserved, should be cleared */
119	__be32 res11;   	/* reserved, should be cleared */
120	__be32 res12;   	/* reserved, should be cleared */
121	__be32 res13;   	/* reserved, should be cleared */
122/* The rest is for Soft-UART only */
123	__be16 supsmr;  	/* 0x90, Shadow UPSMR */
124	__be16 res92;   	/* 0x92, reserved, initialize to 0 */
125	__be32 rx_state;	/* 0x94, RX state, initialize to 0 */
126	__be32 rx_cnt;  	/* 0x98, RX count, initialize to 0 */
127	u8 rx_length;   	/* 0x9C, Char length, set to 1+CL+PEN+1+SL */
128	u8 rx_bitmark;  	/* 0x9D, reserved, initialize to 0 */
129	u8 rx_temp_dlst_qe;     /* 0x9E, reserved, initialize to 0 */
130	u8 res14[0xBC - 0x9F];  /* reserved */
131	__be32 dump_ptr;	/* 0xBC, Dump pointer */
132	__be32 rx_frame_rem;    /* 0xC0, reserved, initialize to 0 */
133	u8 rx_frame_rem_size;   /* 0xC4, reserved, initialize to 0 */
134	u8 tx_mode;     	/* 0xC5, mode, 0=AHDLC, 1=UART */
135	__be16 tx_state;	/* 0xC6, TX state */
136	u8 res15[0xD0 - 0xC8];  /* reserved */
137	__be32 resD0;   	/* 0xD0, reserved, initialize to 0 */
138	u8 resD4;       	/* 0xD4, reserved, initialize to 0 */
139	__be16 resD5;   	/* 0xD5, reserved, initialize to 0 */
140} __attribute__ ((packed));
141
142/* SUPSMR definitions, for Soft-UART only */
143#define UCC_UART_SUPSMR_SL      	0x8000
144#define UCC_UART_SUPSMR_RPM_MASK	0x6000
145#define UCC_UART_SUPSMR_RPM_ODD 	0x0000
146#define UCC_UART_SUPSMR_RPM_LOW 	0x2000
147#define UCC_UART_SUPSMR_RPM_EVEN	0x4000
148#define UCC_UART_SUPSMR_RPM_HIGH	0x6000
149#define UCC_UART_SUPSMR_PEN     	0x1000
150#define UCC_UART_SUPSMR_TPM_MASK	0x0C00
151#define UCC_UART_SUPSMR_TPM_ODD 	0x0000
152#define UCC_UART_SUPSMR_TPM_LOW 	0x0400
153#define UCC_UART_SUPSMR_TPM_EVEN	0x0800
154#define UCC_UART_SUPSMR_TPM_HIGH	0x0C00
155#define UCC_UART_SUPSMR_FRZ     	0x0100
156#define UCC_UART_SUPSMR_UM_MASK 	0x00c0
157#define UCC_UART_SUPSMR_UM_NORMAL       0x0000
158#define UCC_UART_SUPSMR_UM_MAN_MULTI    0x0040
159#define UCC_UART_SUPSMR_UM_AUTO_MULTI   0x00c0
160#define UCC_UART_SUPSMR_CL_MASK 	0x0030
161#define UCC_UART_SUPSMR_CL_8    	0x0030
162#define UCC_UART_SUPSMR_CL_7    	0x0020
163#define UCC_UART_SUPSMR_CL_6    	0x0010
164#define UCC_UART_SUPSMR_CL_5    	0x0000
165
166#define UCC_UART_TX_STATE_AHDLC 	0x00
167#define UCC_UART_TX_STATE_UART  	0x01
168#define UCC_UART_TX_STATE_X1    	0x00
169#define UCC_UART_TX_STATE_X16   	0x80
170
171#define UCC_UART_PRAM_ALIGNMENT 0x100
172
173#define UCC_UART_SIZE_OF_BD     UCC_SLOW_SIZE_OF_BD
174#define NUM_CONTROL_CHARS       8
175
176/* Private per-port data structure */
177struct uart_qe_port {
178	struct uart_port port;
179	struct ucc_slow __iomem *uccp;
180	struct ucc_uart_pram __iomem *uccup;
181	struct ucc_slow_info us_info;
182	struct ucc_slow_private *us_private;
183	struct device_node *np;
184	unsigned int ucc_num;   /* First ucc is 0, not 1 */
185
186	u16 rx_nrfifos;
187	u16 rx_fifosize;
188	u16 tx_nrfifos;
189	u16 tx_fifosize;
190	int wait_closing;
191	u32 flags;
192	struct qe_bd __iomem *rx_bd_base;
193	struct qe_bd __iomem *rx_cur;
194	struct qe_bd __iomem *tx_bd_base;
195	struct qe_bd __iomem *tx_cur;
196	unsigned char *tx_buf;
197	unsigned char *rx_buf;
198	void *bd_virt;  	/* virtual address of the BD buffers */
199	dma_addr_t bd_dma_addr; /* bus address of the BD buffers */
200	unsigned int bd_size;   /* size of BD buffer space */
201};
202
203static struct uart_driver ucc_uart_driver = {
204	.owner  	= THIS_MODULE,
205	.driver_name    = "ucc_uart",
206	.dev_name       = "ttyQE",
207	.major  	= SERIAL_QE_MAJOR,
208	.minor  	= SERIAL_QE_MINOR,
209	.nr     	= UCC_MAX_UART,
210};
211
212/*
213 * Virtual to physical address translation.
214 *
215 * Given the virtual address for a character buffer, this function returns
216 * the physical (DMA) equivalent.
217 */
218static inline dma_addr_t cpu2qe_addr(void *addr, struct uart_qe_port *qe_port)
219{
220	if (likely((addr >= qe_port->bd_virt)) &&
221	    (addr < (qe_port->bd_virt + qe_port->bd_size)))
222		return qe_port->bd_dma_addr + (addr - qe_port->bd_virt);
223
224	/* something nasty happened */
225	printk(KERN_ERR "%s: addr=%p\n", __func__, addr);
226	BUG();
227	return 0;
228}
229
230/*
231 * Physical to virtual address translation.
232 *
233 * Given the physical (DMA) address for a character buffer, this function
234 * returns the virtual equivalent.
235 */
236static inline void *qe2cpu_addr(dma_addr_t addr, struct uart_qe_port *qe_port)
237{
238	/* sanity check */
239	if (likely((addr >= qe_port->bd_dma_addr) &&
240		   (addr < (qe_port->bd_dma_addr + qe_port->bd_size))))
241		return qe_port->bd_virt + (addr - qe_port->bd_dma_addr);
242
243	/* something nasty happened */
244	printk(KERN_ERR "%s: addr=%llx\n", __func__, (u64)addr);
245	BUG();
246	return NULL;
247}
248
249/*
250 * Return 1 if the QE is done transmitting all buffers for this port
251 *
252 * This function scans each BD in sequence.  If we find a BD that is not
253 * ready (READY=1), then we return 0 indicating that the QE is still sending
254 * data.  If we reach the last BD (WRAP=1), then we know we've scanned
255 * the entire list, and all BDs are done.
256 */
257static unsigned int qe_uart_tx_empty(struct uart_port *port)
258{
259	struct uart_qe_port *qe_port =
260		container_of(port, struct uart_qe_port, port);
261	struct qe_bd __iomem *bdp = qe_port->tx_bd_base;
262
263	while (1) {
264		if (ioread16be(&bdp->status) & BD_SC_READY)
265			/* This BD is not done, so return "not done" */
266			return 0;
267
268		if (ioread16be(&bdp->status) & BD_SC_WRAP)
269			/*
270			 * This BD is done and it's the last one, so return
271			 * "done"
272			 */
273			return 1;
274
275		bdp++;
276	}
277}
278
279/*
280 * Set the modem control lines
281 *
282 * Although the QE can control the modem control lines (e.g. CTS), we
283 * don't need that support. This function must exist, however, otherwise
284 * the kernel will panic.
285 */
286static void qe_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
287{
288}
289
290/*
291 * Get the current modem control line status
292 *
293 * Although the QE can control the modem control lines (e.g. CTS), this
294 * driver currently doesn't support that, so we always return Carrier
295 * Detect, Data Set Ready, and Clear To Send.
296 */
297static unsigned int qe_uart_get_mctrl(struct uart_port *port)
298{
299	return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
300}
301
302/*
303 * Disable the transmit interrupt.
304 *
305 * Although this function is called "stop_tx", it does not actually stop
306 * transmission of data.  Instead, it tells the QE to not generate an
307 * interrupt when the UCC is finished sending characters.
308 */
309static void qe_uart_stop_tx(struct uart_port *port)
310{
311	struct uart_qe_port *qe_port =
312		container_of(port, struct uart_qe_port, port);
313
314	qe_clrbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
315}
316
317/*
318 * Transmit as many characters to the HW as possible.
319 *
320 * This function will attempt to stuff of all the characters from the
321 * kernel's transmit buffer into TX BDs.
322 *
323 * A return value of non-zero indicates that it successfully stuffed all
324 * characters from the kernel buffer.
325 *
326 * A return value of zero indicates that there are still characters in the
327 * kernel's buffer that have not been transmitted, but there are no more BDs
328 * available.  This function should be called again after a BD has been made
329 * available.
330 */
331static int qe_uart_tx_pump(struct uart_qe_port *qe_port)
332{
333	struct qe_bd __iomem *bdp;
334	unsigned char *p;
335	unsigned int count;
336	struct uart_port *port = &qe_port->port;
337	struct circ_buf *xmit = &port->state->xmit;
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(ioread32be(&bdp->buf), qe_port);
345
346		*p++ = port->x_char;
347		iowrite16be(1, &bdp->length);
348		qe_setbits_be16(&bdp->status, BD_SC_READY);
349		/* Get next BD. */
350		if (ioread16be(&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 (!(ioread16be(&bdp->status) & BD_SC_READY) && !uart_circ_empty(xmit)) {
370		count = 0;
371		p = qe2cpu_addr(ioread32be(&bdp->buf), qe_port);
372		while (count < qe_port->tx_fifosize) {
373			*p++ = xmit->buf[xmit->tail];
374			uart_xmit_advance(port, 1);
375			count++;
376			if (uart_circ_empty(xmit))
377				break;
378		}
379
380		iowrite16be(count, &bdp->length);
381		qe_setbits_be16(&bdp->status, BD_SC_READY);
382
383		/* Get next BD. */
384		if (ioread16be(&bdp->status) & BD_SC_WRAP)
385			bdp = qe_port->tx_bd_base;
386		else
387			bdp++;
388	}
389	qe_port->tx_cur = bdp;
390
391	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
392		uart_write_wakeup(port);
393
394	if (uart_circ_empty(xmit)) {
395		/* The kernel buffer is empty, so turn off TX interrupts.  We
396		   don't need to be told when the QE is finished transmitting
397		   the data. */
398		qe_uart_stop_tx(port);
399		return 0;
400	}
401
402	return 1;
403}
404
405/*
406 * Start transmitting data
407 *
408 * This function will start transmitting any available data, if the port
409 * isn't already transmitting data.
410 */
411static void qe_uart_start_tx(struct uart_port *port)
412{
413	struct uart_qe_port *qe_port =
414		container_of(port, struct uart_qe_port, port);
415
416	/* If we currently are transmitting, then just return */
417	if (ioread16be(&qe_port->uccp->uccm) & UCC_UART_UCCE_TX)
418		return;
419
420	/* Otherwise, pump the port and start transmission */
421	if (qe_uart_tx_pump(qe_port))
422		qe_setbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
423}
424
425/*
426 * Stop transmitting data
427 */
428static void qe_uart_stop_rx(struct uart_port *port)
429{
430	struct uart_qe_port *qe_port =
431		container_of(port, struct uart_qe_port, port);
432
433	qe_clrbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
434}
435
436/* Start or stop sending  break signal
437 *
438 * This function controls the sending of a break signal.  If break_state=1,
439 * then we start sending a break signal.  If break_state=0, then we stop
440 * sending the break signal.
441 */
442static void qe_uart_break_ctl(struct uart_port *port, int break_state)
443{
444	struct uart_qe_port *qe_port =
445		container_of(port, struct uart_qe_port, port);
446
447	if (break_state)
448		ucc_slow_stop_tx(qe_port->us_private);
449	else
450		ucc_slow_restart_tx(qe_port->us_private);
451}
452
453/* ISR helper function for receiving character.
454 *
455 * This function is called by the ISR to handling receiving characters
456 */
457static void qe_uart_int_rx(struct uart_qe_port *qe_port)
458{
459	int i;
460	unsigned char ch, *cp;
461	struct uart_port *port = &qe_port->port;
462	struct tty_port *tport = &port->state->port;
463	struct qe_bd __iomem *bdp;
464	u16 status;
465	unsigned int flg;
466
467	/* Just loop through the closed BDs and copy the characters into
468	 * the buffer.
469	 */
470	bdp = qe_port->rx_cur;
471	while (1) {
472		status = ioread16be(&bdp->status);
473
474		/* If this one is empty, then we assume we've read them all */
475		if (status & BD_SC_EMPTY)
476			break;
477
478		/* get number of characters, and check space in RX buffer */
479		i = ioread16be(&bdp->length);
480
481		/* If we don't have enough room in RX buffer for the entire BD,
482		 * then we try later, which will be the next RX interrupt.
483		 */
484		if (tty_buffer_request_room(tport, i) < i) {
485			dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n");
486			return;
487		}
488
489		/* get pointer */
490		cp = qe2cpu_addr(ioread32be(&bdp->buf), qe_port);
491
492		/* loop through the buffer */
493		while (i-- > 0) {
494			ch = *cp++;
495			port->icount.rx++;
496			flg = TTY_NORMAL;
497
498			if (!i && status &
499			    (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
500				goto handle_error;
501			if (uart_handle_sysrq_char(port, ch))
502				continue;
503
504error_return:
505			tty_insert_flip_char(tport, ch, flg);
506
507		}
508
509		/* This BD is ready to be used again. Clear status. get next */
510		qe_clrsetbits_be16(&bdp->status,
511				   BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV | BD_SC_ID,
512				   BD_SC_EMPTY);
513		if (ioread16be(&bdp->status) & BD_SC_WRAP)
514			bdp = qe_port->rx_bd_base;
515		else
516			bdp++;
517
518	}
519
520	/* Write back buffer pointer */
521	qe_port->rx_cur = bdp;
522
523	/* Activate BH processing */
524	tty_flip_buffer_push(tport);
525
526	return;
527
528	/* Error processing */
529
530handle_error:
531	/* Statistics */
532	if (status & BD_SC_BR)
533		port->icount.brk++;
534	if (status & BD_SC_PR)
535		port->icount.parity++;
536	if (status & BD_SC_FR)
537		port->icount.frame++;
538	if (status & BD_SC_OV)
539		port->icount.overrun++;
540
541	/* Mask out ignored conditions */
542	status &= port->read_status_mask;
543
544	/* Handle the remaining ones */
545	if (status & BD_SC_BR)
546		flg = TTY_BREAK;
547	else if (status & BD_SC_PR)
548		flg = TTY_PARITY;
549	else if (status & BD_SC_FR)
550		flg = TTY_FRAME;
551
552	/* Overrun does not affect the current character ! */
553	if (status & BD_SC_OV)
554		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
555	port->sysrq = 0;
556	goto error_return;
557}
558
559/* Interrupt handler
560 *
561 * This interrupt handler is called after a BD is processed.
562 */
563static irqreturn_t qe_uart_int(int irq, void *data)
564{
565	struct uart_qe_port *qe_port = (struct uart_qe_port *) data;
566	struct ucc_slow __iomem *uccp = qe_port->uccp;
567	u16 events;
568
569	/* Clear the interrupts */
570	events = ioread16be(&uccp->ucce);
571	iowrite16be(events, &uccp->ucce);
572
573	if (events & UCC_UART_UCCE_BRKE)
574		uart_handle_break(&qe_port->port);
575
576	if (events & UCC_UART_UCCE_RX)
577		qe_uart_int_rx(qe_port);
578
579	if (events & UCC_UART_UCCE_TX)
580		qe_uart_tx_pump(qe_port);
581
582	return events ? IRQ_HANDLED : IRQ_NONE;
583}
584
585/* Initialize buffer descriptors
586 *
587 * This function initializes all of the RX and TX buffer descriptors.
588 */
589static void qe_uart_initbd(struct uart_qe_port *qe_port)
590{
591	int i;
592	void *bd_virt;
593	struct qe_bd __iomem *bdp;
594
595	/* Set the physical address of the host memory buffers in the buffer
596	 * descriptors, and the virtual address for us to work with.
597	 */
598	bd_virt = qe_port->bd_virt;
599	bdp = qe_port->rx_bd_base;
600	qe_port->rx_cur = qe_port->rx_bd_base;
601	for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) {
602		iowrite16be(BD_SC_EMPTY | BD_SC_INTRPT, &bdp->status);
603		iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf);
604		iowrite16be(0, &bdp->length);
605		bd_virt += qe_port->rx_fifosize;
606		bdp++;
607	}
608
609	/* */
610	iowrite16be(BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT, &bdp->status);
611	iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf);
612	iowrite16be(0, &bdp->length);
613
614	/* Set the physical address of the host memory
615	 * buffers in the buffer descriptors, and the
616	 * virtual address for us to work with.
617	 */
618	bd_virt = qe_port->bd_virt +
619		L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
620	qe_port->tx_cur = qe_port->tx_bd_base;
621	bdp = qe_port->tx_bd_base;
622	for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) {
623		iowrite16be(BD_SC_INTRPT, &bdp->status);
624		iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf);
625		iowrite16be(0, &bdp->length);
626		bd_virt += qe_port->tx_fifosize;
627		bdp++;
628	}
629
630	/* Loopback requires the preamble bit to be set on the first TX BD */
631#ifdef LOOPBACK
632	qe_setbits_be16(&qe_port->tx_cur->status, BD_SC_P);
633#endif
634
635	iowrite16be(BD_SC_WRAP | BD_SC_INTRPT, &bdp->status);
636	iowrite32be(cpu2qe_addr(bd_virt, qe_port), &bdp->buf);
637	iowrite16be(0, &bdp->length);
638}
639
640/*
641 * Initialize a UCC for UART.
642 *
643 * This function configures a given UCC to be used as a UART device. Basic
644 * UCC initialization is handled in qe_uart_request_port().  This function
645 * does all the UART-specific stuff.
646 */
647static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
648{
649	u32 cecr_subblock;
650	struct ucc_slow __iomem *uccp = qe_port->uccp;
651	struct ucc_uart_pram __iomem *uccup = qe_port->uccup;
652
653	unsigned int i;
654
655	/* First, disable TX and RX in the UCC */
656	ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
657
658	/* Program the UCC UART parameter RAM */
659	iowrite8(UCC_BMR_GBL | UCC_BMR_BO_BE, &uccup->common.rbmr);
660	iowrite8(UCC_BMR_GBL | UCC_BMR_BO_BE, &uccup->common.tbmr);
661	iowrite16be(qe_port->rx_fifosize, &uccup->common.mrblr);
662	iowrite16be(0x10, &uccup->maxidl);
663	iowrite16be(1, &uccup->brkcr);
664	iowrite16be(0, &uccup->parec);
665	iowrite16be(0, &uccup->frmec);
666	iowrite16be(0, &uccup->nosec);
667	iowrite16be(0, &uccup->brkec);
668	iowrite16be(0, &uccup->uaddr[0]);
669	iowrite16be(0, &uccup->uaddr[1]);
670	iowrite16be(0, &uccup->toseq);
671	for (i = 0; i < 8; i++)
672		iowrite16be(0xC000, &uccup->cchars[i]);
673	iowrite16be(0xc0ff, &uccup->rccm);
674
675	/* Configure the GUMR registers for UART */
676	if (soft_uart) {
677		/* Soft-UART requires a 1X multiplier for TX */
678		qe_clrsetbits_be32(&uccp->gumr_l,
679				   UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK | UCC_SLOW_GUMR_L_RDCR_MASK,
680				   UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 | UCC_SLOW_GUMR_L_RDCR_16);
681
682		qe_clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
683				   UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
684	} else {
685		qe_clrsetbits_be32(&uccp->gumr_l,
686				   UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK | UCC_SLOW_GUMR_L_RDCR_MASK,
687				   UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 | UCC_SLOW_GUMR_L_RDCR_16);
688
689		qe_clrsetbits_be32(&uccp->gumr_h,
690				   UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX,
691				   UCC_SLOW_GUMR_H_RFW);
692	}
693
694#ifdef LOOPBACK
695	qe_clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
696			   UCC_SLOW_GUMR_L_DIAG_LOOP);
697	qe_clrsetbits_be32(&uccp->gumr_h,
698			   UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN,
699			   UCC_SLOW_GUMR_H_CDS);
700#endif
701
702	/* Disable rx interrupts  and clear all pending events.  */
703	iowrite16be(0, &uccp->uccm);
704	iowrite16be(0xffff, &uccp->ucce);
705	iowrite16be(0x7e7e, &uccp->udsr);
706
707	/* Initialize UPSMR */
708	iowrite16be(0, &uccp->upsmr);
709
710	if (soft_uart) {
711		iowrite16be(0x30, &uccup->supsmr);
712		iowrite16be(0, &uccup->res92);
713		iowrite32be(0, &uccup->rx_state);
714		iowrite32be(0, &uccup->rx_cnt);
715		iowrite8(0, &uccup->rx_bitmark);
716		iowrite8(10, &uccup->rx_length);
717		iowrite32be(0x4000, &uccup->dump_ptr);
718		iowrite8(0, &uccup->rx_temp_dlst_qe);
719		iowrite32be(0, &uccup->rx_frame_rem);
720		iowrite8(0, &uccup->rx_frame_rem_size);
721		/* Soft-UART requires TX to be 1X */
722		iowrite8(UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1,
723			    &uccup->tx_mode);
724		iowrite16be(0, &uccup->tx_state);
725		iowrite8(0, &uccup->resD4);
726		iowrite16be(0, &uccup->resD5);
727
728		/* Set UART mode.
729		 * Enable receive and transmit.
730		 */
731
732		/* From the microcode errata:
733		 * 1.GUMR_L register, set mode=0010 (QMC).
734		 * 2.Set GUMR_H[17] bit. (UART/AHDLC mode).
735		 * 3.Set GUMR_H[19:20] (Transparent mode)
736		 * 4.Clear GUMR_H[26] (RFW)
737		 * ...
738		 * 6.Receiver must use 16x over sampling
739		 */
740		qe_clrsetbits_be32(&uccp->gumr_l,
741				   UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK | UCC_SLOW_GUMR_L_RDCR_MASK,
742				   UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 | UCC_SLOW_GUMR_L_RDCR_16);
743
744		qe_clrsetbits_be32(&uccp->gumr_h,
745				   UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN,
746				   UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL);
747
748#ifdef LOOPBACK
749		qe_clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
750				   UCC_SLOW_GUMR_L_DIAG_LOOP);
751		qe_clrbits_be32(&uccp->gumr_h,
752				UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_CDS);
753#endif
754
755		cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
756		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
757			QE_CR_PROTOCOL_UNSPECIFIED, 0);
758	} else {
759		cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
760		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
761			QE_CR_PROTOCOL_UART, 0);
762	}
763}
764
765/*
766 * Initialize the port.
767 */
768static int qe_uart_startup(struct uart_port *port)
769{
770	struct uart_qe_port *qe_port =
771		container_of(port, struct uart_qe_port, port);
772	int ret;
773
774	/*
775	 * If we're using Soft-UART mode, then we need to make sure the
776	 * firmware has been uploaded first.
777	 */
778	if (soft_uart && !firmware_loaded) {
779		dev_err(port->dev, "Soft-UART firmware not uploaded\n");
780		return -ENODEV;
781	}
782
783	qe_uart_initbd(qe_port);
784	qe_uart_init_ucc(qe_port);
785
786	/* Install interrupt handler. */
787	ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart",
788		qe_port);
789	if (ret) {
790		dev_err(port->dev, "could not claim IRQ %u\n", port->irq);
791		return ret;
792	}
793
794	/* Startup rx-int */
795	qe_setbits_be16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
796	ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX);
797
798	return 0;
799}
800
801/*
802 * Shutdown the port.
803 */
804static void qe_uart_shutdown(struct uart_port *port)
805{
806	struct uart_qe_port *qe_port =
807		container_of(port, struct uart_qe_port, port);
808	struct ucc_slow __iomem *uccp = qe_port->uccp;
809	unsigned int timeout = 20;
810
811	/* Disable RX and TX */
812
813	/* Wait for all the BDs marked sent */
814	while (!qe_uart_tx_empty(port)) {
815		if (!--timeout) {
816			dev_warn(port->dev, "shutdown timeout\n");
817			break;
818		}
819		set_current_state(TASK_UNINTERRUPTIBLE);
820		schedule_timeout(2);
821	}
822
823	if (qe_port->wait_closing) {
824		/* Wait a bit longer */
825		set_current_state(TASK_UNINTERRUPTIBLE);
826		schedule_timeout(qe_port->wait_closing);
827	}
828
829	/* Stop uarts */
830	ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
831	qe_clrbits_be16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX);
832
833	/* Shut them really down and reinit buffer descriptors */
834	ucc_slow_graceful_stop_tx(qe_port->us_private);
835	qe_uart_initbd(qe_port);
836
837	free_irq(port->irq, qe_port);
838}
839
840/*
841 * Set the serial port parameters.
842 */
843static void qe_uart_set_termios(struct uart_port *port,
844				struct ktermios *termios,
845				const struct ktermios *old)
846{
847	struct uart_qe_port *qe_port =
848		container_of(port, struct uart_qe_port, port);
849	struct ucc_slow __iomem *uccp = qe_port->uccp;
850	unsigned int baud;
851	unsigned long flags;
852	u16 upsmr = ioread16be(&uccp->upsmr);
853	struct ucc_uart_pram __iomem *uccup = qe_port->uccup;
854	u16 supsmr = ioread16be(&uccup->supsmr);
855
856	/* byte size */
857	upsmr &= UCC_UART_UPSMR_CL_MASK;
858	supsmr &= UCC_UART_SUPSMR_CL_MASK;
859
860	switch (termios->c_cflag & CSIZE) {
861	case CS5:
862		upsmr |= UCC_UART_UPSMR_CL_5;
863		supsmr |= UCC_UART_SUPSMR_CL_5;
864		break;
865	case CS6:
866		upsmr |= UCC_UART_UPSMR_CL_6;
867		supsmr |= UCC_UART_SUPSMR_CL_6;
868		break;
869	case CS7:
870		upsmr |= UCC_UART_UPSMR_CL_7;
871		supsmr |= UCC_UART_SUPSMR_CL_7;
872		break;
873	default:	/* case CS8 */
874		upsmr |= UCC_UART_UPSMR_CL_8;
875		supsmr |= UCC_UART_SUPSMR_CL_8;
876		break;
877	}
878
879	/* If CSTOPB is set, we want two stop bits */
880	if (termios->c_cflag & CSTOPB) {
881		upsmr |= UCC_UART_UPSMR_SL;
882		supsmr |= UCC_UART_SUPSMR_SL;
883	}
884
885	if (termios->c_cflag & PARENB) {
886		upsmr |= UCC_UART_UPSMR_PEN;
887		supsmr |= UCC_UART_SUPSMR_PEN;
888
889		if (!(termios->c_cflag & PARODD)) {
890			upsmr &= ~(UCC_UART_UPSMR_RPM_MASK |
891				   UCC_UART_UPSMR_TPM_MASK);
892			upsmr |= UCC_UART_UPSMR_RPM_EVEN |
893				UCC_UART_UPSMR_TPM_EVEN;
894			supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK |
895				    UCC_UART_SUPSMR_TPM_MASK);
896			supsmr |= UCC_UART_SUPSMR_RPM_EVEN |
897				UCC_UART_SUPSMR_TPM_EVEN;
898		}
899	}
900
901	/*
902	 * Set up parity check flag
903	 */
904	port->read_status_mask = BD_SC_EMPTY | BD_SC_OV;
905	if (termios->c_iflag & INPCK)
906		port->read_status_mask |= BD_SC_FR | BD_SC_PR;
907	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
908		port->read_status_mask |= BD_SC_BR;
909
910	/*
911	 * Characters to ignore
912	 */
913	port->ignore_status_mask = 0;
914	if (termios->c_iflag & IGNPAR)
915		port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
916	if (termios->c_iflag & IGNBRK) {
917		port->ignore_status_mask |= BD_SC_BR;
918		/*
919		 * If we're ignore parity and break indicators, ignore
920		 * overruns too.  (For real raw support).
921		 */
922		if (termios->c_iflag & IGNPAR)
923			port->ignore_status_mask |= BD_SC_OV;
924	}
925	/*
926	 * !!! ignore all characters if CREAD is not set
927	 */
928	if ((termios->c_cflag & CREAD) == 0)
929		port->read_status_mask &= ~BD_SC_EMPTY;
930
931	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
932
933	/* Do we really need a spinlock here? */
934	uart_port_lock_irqsave(port, &flags);
935
936	/* Update the per-port timeout. */
937	uart_update_timeout(port, termios->c_cflag, baud);
938
939	iowrite16be(upsmr, &uccp->upsmr);
940	if (soft_uart) {
941		iowrite16be(supsmr, &uccup->supsmr);
942		iowrite8(tty_get_frame_size(termios->c_cflag), &uccup->rx_length);
943
944		/* Soft-UART requires a 1X multiplier for TX */
945		qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
946		qe_setbrg(qe_port->us_info.tx_clock, baud, 1);
947	} else {
948		qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
949		qe_setbrg(qe_port->us_info.tx_clock, baud, 16);
950	}
951
952	uart_port_unlock_irqrestore(port, flags);
953}
954
955/*
956 * Return a pointer to a string that describes what kind of port this is.
957 */
958static const char *qe_uart_type(struct uart_port *port)
959{
960	return "QE";
961}
962
963/*
964 * Allocate any memory and I/O resources required by the port.
965 */
966static int qe_uart_request_port(struct uart_port *port)
967{
968	int ret;
969	struct uart_qe_port *qe_port =
970		container_of(port, struct uart_qe_port, port);
971	struct ucc_slow_info *us_info = &qe_port->us_info;
972	struct ucc_slow_private *uccs;
973	unsigned int rx_size, tx_size;
974	void *bd_virt;
975	dma_addr_t bd_dma_addr = 0;
976
977	ret = ucc_slow_init(us_info, &uccs);
978	if (ret) {
979		dev_err(port->dev, "could not initialize UCC%u\n",
980		       qe_port->ucc_num);
981		return ret;
982	}
983
984	qe_port->us_private = uccs;
985	qe_port->uccp = uccs->us_regs;
986	qe_port->uccup = (struct ucc_uart_pram __iomem *)uccs->us_pram;
987	qe_port->rx_bd_base = uccs->rx_bd;
988	qe_port->tx_bd_base = uccs->tx_bd;
989
990	/*
991	 * Allocate the transmit and receive data buffers.
992	 */
993
994	rx_size = L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
995	tx_size = L1_CACHE_ALIGN(qe_port->tx_nrfifos * qe_port->tx_fifosize);
996
997	bd_virt = dma_alloc_coherent(port->dev, rx_size + tx_size, &bd_dma_addr,
998		GFP_KERNEL);
999	if (!bd_virt) {
1000		dev_err(port->dev, "could not allocate buffer descriptors\n");
1001		return -ENOMEM;
1002	}
1003
1004	qe_port->bd_virt = bd_virt;
1005	qe_port->bd_dma_addr = bd_dma_addr;
1006	qe_port->bd_size = rx_size + tx_size;
1007
1008	qe_port->rx_buf = bd_virt;
1009	qe_port->tx_buf = qe_port->rx_buf + rx_size;
1010
1011	return 0;
1012}
1013
1014/*
1015 * Configure the port.
1016 *
1017 * We say we're a CPM-type port because that's mostly true.  Once the device
1018 * is configured, this driver operates almost identically to the CPM serial
1019 * driver.
1020 */
1021static void qe_uart_config_port(struct uart_port *port, int flags)
1022{
1023	if (flags & UART_CONFIG_TYPE) {
1024		port->type = PORT_CPM;
1025		qe_uart_request_port(port);
1026	}
1027}
1028
1029/*
1030 * Release any memory and I/O resources that were allocated in
1031 * qe_uart_request_port().
1032 */
1033static void qe_uart_release_port(struct uart_port *port)
1034{
1035	struct uart_qe_port *qe_port =
1036		container_of(port, struct uart_qe_port, port);
1037	struct ucc_slow_private *uccs = qe_port->us_private;
1038
1039	dma_free_coherent(port->dev, qe_port->bd_size, qe_port->bd_virt,
1040			  qe_port->bd_dma_addr);
1041
1042	ucc_slow_free(uccs);
1043}
1044
1045/*
1046 * Verify that the data in serial_struct is suitable for this device.
1047 */
1048static int qe_uart_verify_port(struct uart_port *port,
1049			       struct serial_struct *ser)
1050{
1051	if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
1052		return -EINVAL;
1053
1054	if (ser->irq < 0 || ser->irq >= nr_irqs)
1055		return -EINVAL;
1056
1057	if (ser->baud_base < 9600)
1058		return -EINVAL;
1059
1060	return 0;
1061}
1062/* UART operations
1063 *
1064 * Details on these functions can be found in Documentation/driver-api/serial/driver.rst
1065 */
1066static const struct uart_ops qe_uart_pops = {
1067	.tx_empty       = qe_uart_tx_empty,
1068	.set_mctrl      = qe_uart_set_mctrl,
1069	.get_mctrl      = qe_uart_get_mctrl,
1070	.stop_tx	= qe_uart_stop_tx,
1071	.start_tx       = qe_uart_start_tx,
1072	.stop_rx	= qe_uart_stop_rx,
1073	.break_ctl      = qe_uart_break_ctl,
1074	.startup	= qe_uart_startup,
1075	.shutdown       = qe_uart_shutdown,
1076	.set_termios    = qe_uart_set_termios,
1077	.type   	= qe_uart_type,
1078	.release_port   = qe_uart_release_port,
1079	.request_port   = qe_uart_request_port,
1080	.config_port    = qe_uart_config_port,
1081	.verify_port    = qe_uart_verify_port,
1082};
1083
1084
1085#ifdef CONFIG_PPC32
1086/*
1087 * Obtain the SOC model number and revision level
1088 *
1089 * This function parses the device tree to obtain the SOC model.  It then
1090 * reads the SVR register to the revision.
1091 *
1092 * The device tree stores the SOC model two different ways.
1093 *
1094 * The new way is:
1095 *
1096 *      	cpu@0 {
1097 *      		compatible = "PowerPC,8323";
1098 *      		device_type = "cpu";
1099 *      		...
1100 *
1101 *
1102 * The old way is:
1103 *      	 PowerPC,8323@0 {
1104 *      		device_type = "cpu";
1105 *      		...
1106 *
1107 * This code first checks the new way, and then the old way.
1108 */
1109static unsigned int soc_info(unsigned int *rev_h, unsigned int *rev_l)
1110{
1111	struct device_node *np;
1112	const char *soc_string;
1113	unsigned int svr;
1114	unsigned int soc;
1115
1116	/* Find the CPU node */
1117	np = of_find_node_by_type(NULL, "cpu");
1118	if (!np)
1119		return 0;
1120	/* Find the compatible property */
1121	soc_string = of_get_property(np, "compatible", NULL);
1122	if (!soc_string)
1123		/* No compatible property, so try the name. */
1124		soc_string = np->name;
1125
1126	of_node_put(np);
1127
1128	/* Extract the SOC number from the "PowerPC," string */
1129	if ((sscanf(soc_string, "PowerPC,%u", &soc) != 1) || !soc)
1130		return 0;
1131
1132	/* Get the revision from the SVR */
1133	svr = mfspr(SPRN_SVR);
1134	*rev_h = (svr >> 4) & 0xf;
1135	*rev_l = svr & 0xf;
1136
1137	return soc;
1138}
1139
1140/*
1141 * requst_firmware_nowait() callback function
1142 *
1143 * This function is called by the kernel when a firmware is made available,
1144 * or if it times out waiting for the firmware.
1145 */
1146static void uart_firmware_cont(const struct firmware *fw, void *context)
1147{
1148	struct qe_firmware *firmware;
1149	struct device *dev = context;
1150	int ret;
1151
1152	if (!fw) {
1153		dev_err(dev, "firmware not found\n");
1154		return;
1155	}
1156
1157	firmware = (struct qe_firmware *) fw->data;
1158
1159	if (be32_to_cpu(firmware->header.length) != fw->size) {
1160		dev_err(dev, "invalid firmware\n");
1161		goto out;
1162	}
1163
1164	ret = qe_upload_firmware(firmware);
1165	if (ret) {
1166		dev_err(dev, "could not load firmware\n");
1167		goto out;
1168	}
1169
1170	firmware_loaded = 1;
1171 out:
1172	release_firmware(fw);
1173}
1174
1175static int soft_uart_init(struct platform_device *ofdev)
1176{
1177	struct device_node *np = ofdev->dev.of_node;
1178	struct qe_firmware_info *qe_fw_info;
1179	int ret;
1180
1181	if (of_property_read_bool(np, "soft-uart")) {
1182		dev_dbg(&ofdev->dev, "using Soft-UART mode\n");
1183		soft_uart = 1;
1184	} else {
1185		return 0;
1186	}
1187
1188	qe_fw_info = qe_get_firmware_info();
1189
1190	/* Check if the firmware has been uploaded. */
1191	if (qe_fw_info && strstr(qe_fw_info->id, "Soft-UART")) {
1192		firmware_loaded = 1;
1193	} else {
1194		char filename[32];
1195		unsigned int soc;
1196		unsigned int rev_h;
1197		unsigned int rev_l;
1198
1199		soc = soc_info(&rev_h, &rev_l);
1200		if (!soc) {
1201			dev_err(&ofdev->dev, "unknown CPU model\n");
1202			return -ENXIO;
1203		}
1204		sprintf(filename, "fsl_qe_ucode_uart_%u_%u%u.bin",
1205			soc, rev_h, rev_l);
1206
1207		dev_info(&ofdev->dev, "waiting for firmware %s\n",
1208			 filename);
1209
1210		/*
1211		 * We call request_firmware_nowait instead of
1212		 * request_firmware so that the driver can load and
1213		 * initialize the ports without holding up the rest of
1214		 * the kernel.  If hotplug support is enabled in the
1215		 * kernel, then we use it.
1216		 */
1217		ret = request_firmware_nowait(THIS_MODULE,
1218					      FW_ACTION_UEVENT, filename, &ofdev->dev,
1219					      GFP_KERNEL, &ofdev->dev, uart_firmware_cont);
1220		if (ret) {
1221			dev_err(&ofdev->dev,
1222				"could not load firmware %s\n",
1223				filename);
1224			return ret;
1225		}
1226	}
1227	return 0;
1228}
1229
1230#else /* !CONFIG_PPC32 */
1231
1232static int soft_uart_init(struct platform_device *ofdev)
1233{
1234	return 0;
1235}
1236
1237#endif
1238
1239
1240static int ucc_uart_probe(struct platform_device *ofdev)
1241{
1242	struct device_node *np = ofdev->dev.of_node;
1243	const char *sprop;      /* String OF properties */
1244	struct uart_qe_port *qe_port = NULL;
1245	struct resource res;
1246	u32 val;
1247	int ret;
1248
1249	/*
1250	 * Determine if we need Soft-UART mode
1251	 */
1252	ret = soft_uart_init(ofdev);
1253	if (ret)
1254		return ret;
1255
1256	qe_port = kzalloc(sizeof(struct uart_qe_port), GFP_KERNEL);
1257	if (!qe_port) {
1258		dev_err(&ofdev->dev, "can't allocate QE port structure\n");
1259		return -ENOMEM;
1260	}
1261
1262	/* Search for IRQ and mapbase */
1263	ret = of_address_to_resource(np, 0, &res);
1264	if (ret) {
1265		dev_err(&ofdev->dev, "missing 'reg' property in device tree\n");
1266		goto out_free;
1267	}
1268	if (!res.start) {
1269		dev_err(&ofdev->dev, "invalid 'reg' property in device tree\n");
1270		ret = -EINVAL;
1271		goto out_free;
1272	}
1273	qe_port->port.mapbase = res.start;
1274
1275	/* Get the UCC number (device ID) */
1276	/* UCCs are numbered 1-7 */
1277	if (of_property_read_u32(np, "cell-index", &val)) {
1278		if (of_property_read_u32(np, "device-id", &val)) {
1279			dev_err(&ofdev->dev, "UCC is unspecified in device tree\n");
1280			ret = -EINVAL;
1281			goto out_free;
1282		}
1283	}
1284
1285	if (val < 1 || val > UCC_MAX_NUM) {
1286		dev_err(&ofdev->dev, "no support for UCC%u\n", val);
1287		ret = -ENODEV;
1288		goto out_free;
1289	}
1290	qe_port->ucc_num = val - 1;
1291
1292	/*
1293	 * In the future, we should not require the BRG to be specified in the
1294	 * device tree.  If no clock-source is specified, then just pick a BRG
1295	 * to use.  This requires a new QE library function that manages BRG
1296	 * assignments.
1297	 */
1298
1299	sprop = of_get_property(np, "rx-clock-name", NULL);
1300	if (!sprop) {
1301		dev_err(&ofdev->dev, "missing rx-clock-name in device tree\n");
1302		ret = -ENODEV;
1303		goto out_free;
1304	}
1305
1306	qe_port->us_info.rx_clock = qe_clock_source(sprop);
1307	if ((qe_port->us_info.rx_clock < QE_BRG1) ||
1308	    (qe_port->us_info.rx_clock > QE_BRG16)) {
1309		dev_err(&ofdev->dev, "rx-clock-name must be a BRG for UART\n");
1310		ret = -ENODEV;
1311		goto out_free;
1312	}
1313
1314#ifdef LOOPBACK
1315	/* In internal loopback mode, TX and RX must use the same clock */
1316	qe_port->us_info.tx_clock = qe_port->us_info.rx_clock;
1317#else
1318	sprop = of_get_property(np, "tx-clock-name", NULL);
1319	if (!sprop) {
1320		dev_err(&ofdev->dev, "missing tx-clock-name in device tree\n");
1321		ret = -ENODEV;
1322		goto out_free;
1323	}
1324	qe_port->us_info.tx_clock = qe_clock_source(sprop);
1325#endif
1326	if ((qe_port->us_info.tx_clock < QE_BRG1) ||
1327	    (qe_port->us_info.tx_clock > QE_BRG16)) {
1328		dev_err(&ofdev->dev, "tx-clock-name must be a BRG for UART\n");
1329		ret = -ENODEV;
1330		goto out_free;
1331	}
1332
1333	/* Get the port number, numbered 0-3 */
1334	if (of_property_read_u32(np, "port-number", &val)) {
1335		dev_err(&ofdev->dev, "missing port-number in device tree\n");
1336		ret = -EINVAL;
1337		goto out_free;
1338	}
1339	qe_port->port.line = val;
1340	if (qe_port->port.line >= UCC_MAX_UART) {
1341		dev_err(&ofdev->dev, "port-number must be 0-%u\n",
1342			UCC_MAX_UART - 1);
1343		ret = -EINVAL;
1344		goto out_free;
1345	}
1346
1347	qe_port->port.irq = irq_of_parse_and_map(np, 0);
1348	if (qe_port->port.irq == 0) {
1349		dev_err(&ofdev->dev, "could not map IRQ for UCC%u\n",
1350		       qe_port->ucc_num + 1);
1351		ret = -EINVAL;
1352		goto out_free;
1353	}
1354
1355	/*
1356	 * Newer device trees have an "fsl,qe" compatible property for the QE
1357	 * node, but we still need to support older device trees.
1358	 */
1359	np = of_find_compatible_node(NULL, NULL, "fsl,qe");
1360	if (!np) {
1361		np = of_find_node_by_type(NULL, "qe");
1362		if (!np) {
1363			dev_err(&ofdev->dev, "could not find 'qe' node\n");
1364			ret = -EINVAL;
1365			goto out_free;
1366		}
1367	}
1368
1369	if (of_property_read_u32(np, "brg-frequency", &val)) {
1370		dev_err(&ofdev->dev,
1371		       "missing brg-frequency in device tree\n");
1372		ret = -EINVAL;
1373		goto out_np;
1374	}
1375
1376	if (val)
1377		qe_port->port.uartclk = val;
1378	else {
1379		if (!IS_ENABLED(CONFIG_PPC32)) {
1380			dev_err(&ofdev->dev,
1381				"invalid brg-frequency in device tree\n");
1382			ret = -EINVAL;
1383			goto out_np;
1384		}
1385
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		if (of_property_read_u32(np, "bus-frequency", &val)) {
1392			dev_err(&ofdev->dev,
1393				"missing QE bus-frequency in device tree\n");
1394			ret = -EINVAL;
1395			goto out_np;
1396		}
1397		if (val)
1398			qe_port->port.uartclk = val / 2;
1399		else {
1400			dev_err(&ofdev->dev,
1401				"invalid QE bus-frequency in device tree\n");
1402			ret = -EINVAL;
1403			goto out_np;
1404		}
1405	}
1406
1407	spin_lock_init(&qe_port->port.lock);
1408	qe_port->np = np;
1409	qe_port->port.dev = &ofdev->dev;
1410	qe_port->port.ops = &qe_uart_pops;
1411	qe_port->port.iotype = UPIO_MEM;
1412
1413	qe_port->tx_nrfifos = TX_NUM_FIFO;
1414	qe_port->tx_fifosize = TX_BUF_SIZE;
1415	qe_port->rx_nrfifos = RX_NUM_FIFO;
1416	qe_port->rx_fifosize = RX_BUF_SIZE;
1417
1418	qe_port->wait_closing = UCC_WAIT_CLOSING;
1419	qe_port->port.fifosize = 512;
1420	qe_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
1421
1422	qe_port->us_info.ucc_num = qe_port->ucc_num;
1423	qe_port->us_info.regs = (phys_addr_t) res.start;
1424	qe_port->us_info.irq = qe_port->port.irq;
1425
1426	qe_port->us_info.rx_bd_ring_len = qe_port->rx_nrfifos;
1427	qe_port->us_info.tx_bd_ring_len = qe_port->tx_nrfifos;
1428
1429	/* Make sure ucc_slow_init() initializes both TX and RX */
1430	qe_port->us_info.init_tx = 1;
1431	qe_port->us_info.init_rx = 1;
1432
1433	/* Add the port to the uart sub-system.  This will cause
1434	 * qe_uart_config_port() to be called, so the us_info structure must
1435	 * be initialized.
1436	 */
1437	ret = uart_add_one_port(&ucc_uart_driver, &qe_port->port);
1438	if (ret) {
1439		dev_err(&ofdev->dev, "could not add /dev/ttyQE%u\n",
1440		       qe_port->port.line);
1441		goto out_np;
1442	}
1443
1444	platform_set_drvdata(ofdev, qe_port);
1445
1446	dev_info(&ofdev->dev, "UCC%u assigned to /dev/ttyQE%u\n",
1447		qe_port->ucc_num + 1, qe_port->port.line);
1448
1449	/* Display the mknod command for this device */
1450	dev_dbg(&ofdev->dev, "mknod command is 'mknod /dev/ttyQE%u c %u %u'\n",
1451	       qe_port->port.line, SERIAL_QE_MAJOR,
1452	       SERIAL_QE_MINOR + qe_port->port.line);
1453
1454	return 0;
1455out_np:
1456	of_node_put(np);
1457out_free:
1458	kfree(qe_port);
1459	return ret;
1460}
1461
1462static void ucc_uart_remove(struct platform_device *ofdev)
1463{
1464	struct uart_qe_port *qe_port = platform_get_drvdata(ofdev);
1465
1466	dev_info(&ofdev->dev, "removing /dev/ttyQE%u\n", qe_port->port.line);
1467
1468	uart_remove_one_port(&ucc_uart_driver, &qe_port->port);
1469
1470	of_node_put(qe_port->np);
1471
1472	kfree(qe_port);
1473}
1474
1475static const struct of_device_id ucc_uart_match[] = {
1476	{
1477		.type = "serial",
1478		.compatible = "ucc_uart",
1479	},
1480	{
1481		.compatible = "fsl,t1040-ucc-uart",
1482	},
1483	{},
1484};
1485MODULE_DEVICE_TABLE(of, ucc_uart_match);
1486
1487static struct platform_driver ucc_uart_of_driver = {
1488	.driver = {
1489		.name = "ucc_uart",
1490		.of_match_table    = ucc_uart_match,
1491	},
1492	.probe  	= ucc_uart_probe,
1493	.remove_new 	= ucc_uart_remove,
1494};
1495
1496static int __init ucc_uart_init(void)
1497{
1498	int ret;
1499
1500	printk(KERN_INFO "Freescale QUICC Engine UART device driver\n");
1501#ifdef LOOPBACK
1502	printk(KERN_INFO "ucc-uart: Using loopback mode\n");
1503#endif
1504
1505	ret = uart_register_driver(&ucc_uart_driver);
1506	if (ret) {
1507		printk(KERN_ERR "ucc-uart: could not register UART driver\n");
1508		return ret;
1509	}
1510
1511	ret = platform_driver_register(&ucc_uart_of_driver);
1512	if (ret) {
1513		printk(KERN_ERR
1514		       "ucc-uart: could not register platform driver\n");
1515		uart_unregister_driver(&ucc_uart_driver);
1516	}
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	platform_driver_unregister(&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
1538