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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/serial.h>
21#include <linux/serial_core.h>
22#include <linux/slab.h>
23#include <linux/tty.h>
24#include <linux/tty_flip.h>
25#include <linux/io.h>
26#include <linux/of_address.h>
27#include <linux/of_irq.h>
28#include <linux/of_platform.h>
29#include <linux/dma-mapping.h>
30
31#include <linux/fs_uart_pd.h>
32#include <soc/fsl/qe/ucc_slow.h>
33
34#include <linux/firmware.h>
35#include <asm/reg.h>
36
37/*
38 * The GUMR flag for Soft UART. This would normally be defined in qe.h,
39 * but Soft-UART is a hack and we want to keep everything related to it in
40 * this file.
41 */
42#define UCC_SLOW_GUMR_H_SUART 0x00004000 /* Soft-UART */
43
44/*
45 * soft_uart is 1 if we need to use Soft-UART mode
46 */
47static int soft_uart;
48/*
49 * firmware_loaded is 1 if the firmware has been loaded, 0 otherwise.
50 */
51static int firmware_loaded;
52
53/* Enable this macro to configure all serial ports in internal loopback
54 mode */
55/* #define LOOPBACK */
56
57/* The major and minor device numbers are defined in
58 * http://www.lanana.org/docs/device-list/devices-2.6+.txt. For the QE
59 * UART, we have major number 204 and minor numbers 46 - 49, which are the
60 * same as for the CPM2. This decision was made because no Freescale part
61 * has both a CPM and a QE.
62 */
63#define SERIAL_QE_MAJOR 204
64#define SERIAL_QE_MINOR 46
65
66/* Since we only have minor numbers 46 - 49, there is a hard limit of 4 ports */
67#define UCC_MAX_UART 4
68
69/* The number of buffer descriptors for receiving characters. */
70#define RX_NUM_FIFO 4
71
72/* The number of buffer descriptors for transmitting characters. */
73#define TX_NUM_FIFO 4
74
75/* The maximum size of the character buffer for a single RX BD. */
76#define RX_BUF_SIZE 32
77
78/* The maximum size of the character buffer for a single TX BD. */
79#define TX_BUF_SIZE 32
80
81/*
82 * The number of jiffies to wait after receiving a close command before the
83 * device is actually closed. This allows the last few characters to be
84 * sent over the wire.
85 */
86#define UCC_WAIT_CLOSING 100
87
88struct ucc_uart_pram {
89 struct ucc_slow_pram common;
90 u8 res1[8]; /* reserved */
91 __be16 maxidl; /* Maximum idle chars */
92 __be16 idlc; /* temp idle counter */
93 __be16 brkcr; /* Break count register */
94 __be16 parec; /* receive parity error counter */
95 __be16 frmec; /* receive framing error counter */
96 __be16 nosec; /* receive noise counter */
97 __be16 brkec; /* receive break condition counter */
98 __be16 brkln; /* last received break length */
99 __be16 uaddr[2]; /* UART address character 1 & 2 */
100 __be16 rtemp; /* Temp storage */
101 __be16 toseq; /* Transmit out of sequence char */
102 __be16 cchars[8]; /* control characters 1-8 */
103 __be16 rccm; /* receive control character mask */
104 __be16 rccr; /* receive control character register */
105 __be16 rlbc; /* receive last break character */
106 __be16 res2; /* reserved */
107 __be32 res3; /* reserved, should be cleared */
108 u8 res4; /* reserved, should be cleared */
109 u8 res5[3]; /* reserved, should be cleared */
110 __be32 res6; /* reserved, should be cleared */
111 __be32 res7; /* reserved, should be cleared */
112 __be32 res8; /* reserved, should be cleared */
113 __be32 res9; /* reserved, should be cleared */
114 __be32 res10; /* reserved, should be cleared */
115 __be32 res11; /* reserved, should be cleared */
116 __be32 res12; /* reserved, should be cleared */
117 __be32 res13; /* reserved, should be cleared */
118/* The rest is for Soft-UART only */
119 __be16 supsmr; /* 0x90, Shadow UPSMR */
120 __be16 res92; /* 0x92, reserved, initialize to 0 */
121 __be32 rx_state; /* 0x94, RX state, initialize to 0 */
122 __be32 rx_cnt; /* 0x98, RX count, initialize to 0 */
123 u8 rx_length; /* 0x9C, Char length, set to 1+CL+PEN+1+SL */
124 u8 rx_bitmark; /* 0x9D, reserved, initialize to 0 */
125 u8 rx_temp_dlst_qe; /* 0x9E, reserved, initialize to 0 */
126 u8 res14[0xBC - 0x9F]; /* reserved */
127 __be32 dump_ptr; /* 0xBC, Dump pointer */
128 __be32 rx_frame_rem; /* 0xC0, reserved, initialize to 0 */
129 u8 rx_frame_rem_size; /* 0xC4, reserved, initialize to 0 */
130 u8 tx_mode; /* 0xC5, mode, 0=AHDLC, 1=UART */
131 __be16 tx_state; /* 0xC6, TX state */
132 u8 res15[0xD0 - 0xC8]; /* reserved */
133 __be32 resD0; /* 0xD0, reserved, initialize to 0 */
134 u8 resD4; /* 0xD4, reserved, initialize to 0 */
135 __be16 resD5; /* 0xD5, reserved, initialize to 0 */
136} __attribute__ ((packed));
137
138/* SUPSMR definitions, for Soft-UART only */
139#define UCC_UART_SUPSMR_SL 0x8000
140#define UCC_UART_SUPSMR_RPM_MASK 0x6000
141#define UCC_UART_SUPSMR_RPM_ODD 0x0000
142#define UCC_UART_SUPSMR_RPM_LOW 0x2000
143#define UCC_UART_SUPSMR_RPM_EVEN 0x4000
144#define UCC_UART_SUPSMR_RPM_HIGH 0x6000
145#define UCC_UART_SUPSMR_PEN 0x1000
146#define UCC_UART_SUPSMR_TPM_MASK 0x0C00
147#define UCC_UART_SUPSMR_TPM_ODD 0x0000
148#define UCC_UART_SUPSMR_TPM_LOW 0x0400
149#define UCC_UART_SUPSMR_TPM_EVEN 0x0800
150#define UCC_UART_SUPSMR_TPM_HIGH 0x0C00
151#define UCC_UART_SUPSMR_FRZ 0x0100
152#define UCC_UART_SUPSMR_UM_MASK 0x00c0
153#define UCC_UART_SUPSMR_UM_NORMAL 0x0000
154#define UCC_UART_SUPSMR_UM_MAN_MULTI 0x0040
155#define UCC_UART_SUPSMR_UM_AUTO_MULTI 0x00c0
156#define UCC_UART_SUPSMR_CL_MASK 0x0030
157#define UCC_UART_SUPSMR_CL_8 0x0030
158#define UCC_UART_SUPSMR_CL_7 0x0020
159#define UCC_UART_SUPSMR_CL_6 0x0010
160#define UCC_UART_SUPSMR_CL_5 0x0000
161
162#define UCC_UART_TX_STATE_AHDLC 0x00
163#define UCC_UART_TX_STATE_UART 0x01
164#define UCC_UART_TX_STATE_X1 0x00
165#define UCC_UART_TX_STATE_X16 0x80
166
167#define UCC_UART_PRAM_ALIGNMENT 0x100
168
169#define UCC_UART_SIZE_OF_BD UCC_SLOW_SIZE_OF_BD
170#define NUM_CONTROL_CHARS 8
171
172/* Private per-port data structure */
173struct uart_qe_port {
174 struct uart_port port;
175 struct ucc_slow __iomem *uccp;
176 struct ucc_uart_pram __iomem *uccup;
177 struct ucc_slow_info us_info;
178 struct ucc_slow_private *us_private;
179 struct device_node *np;
180 unsigned int ucc_num; /* First ucc is 0, not 1 */
181
182 u16 rx_nrfifos;
183 u16 rx_fifosize;
184 u16 tx_nrfifos;
185 u16 tx_fifosize;
186 int wait_closing;
187 u32 flags;
188 struct qe_bd *rx_bd_base;
189 struct qe_bd *rx_cur;
190 struct qe_bd *tx_bd_base;
191 struct qe_bd *tx_cur;
192 unsigned char *tx_buf;
193 unsigned char *rx_buf;
194 void *bd_virt; /* virtual address of the BD buffers */
195 dma_addr_t bd_dma_addr; /* bus address of the BD buffers */
196 unsigned int bd_size; /* size of BD buffer space */
197};
198
199static struct uart_driver ucc_uart_driver = {
200 .owner = THIS_MODULE,
201 .driver_name = "ucc_uart",
202 .dev_name = "ttyQE",
203 .major = SERIAL_QE_MAJOR,
204 .minor = SERIAL_QE_MINOR,
205 .nr = UCC_MAX_UART,
206};
207
208/*
209 * Virtual to physical address translation.
210 *
211 * Given the virtual address for a character buffer, this function returns
212 * the physical (DMA) equivalent.
213 */
214static inline dma_addr_t cpu2qe_addr(void *addr, struct uart_qe_port *qe_port)
215{
216 if (likely((addr >= qe_port->bd_virt)) &&
217 (addr < (qe_port->bd_virt + qe_port->bd_size)))
218 return qe_port->bd_dma_addr + (addr - qe_port->bd_virt);
219
220 /* something nasty happened */
221 printk(KERN_ERR "%s: addr=%p\n", __func__, addr);
222 BUG();
223 return 0;
224}
225
226/*
227 * Physical to virtual address translation.
228 *
229 * Given the physical (DMA) address for a character buffer, this function
230 * returns the virtual equivalent.
231 */
232static inline void *qe2cpu_addr(dma_addr_t addr, struct uart_qe_port *qe_port)
233{
234 /* sanity check */
235 if (likely((addr >= qe_port->bd_dma_addr) &&
236 (addr < (qe_port->bd_dma_addr + qe_port->bd_size))))
237 return qe_port->bd_virt + (addr - qe_port->bd_dma_addr);
238
239 /* something nasty happened */
240 printk(KERN_ERR "%s: addr=%llx\n", __func__, (u64)addr);
241 BUG();
242 return NULL;
243}
244
245/*
246 * Return 1 if the QE is done transmitting all buffers for this port
247 *
248 * This function scans each BD in sequence. If we find a BD that is not
249 * ready (READY=1), then we return 0 indicating that the QE is still sending
250 * data. If we reach the last BD (WRAP=1), then we know we've scanned
251 * the entire list, and all BDs are done.
252 */
253static unsigned int qe_uart_tx_empty(struct uart_port *port)
254{
255 struct uart_qe_port *qe_port =
256 container_of(port, struct uart_qe_port, port);
257 struct qe_bd *bdp = qe_port->tx_bd_base;
258
259 while (1) {
260 if (in_be16(&bdp->status) & BD_SC_READY)
261 /* This BD is not done, so return "not done" */
262 return 0;
263
264 if (in_be16(&bdp->status) & BD_SC_WRAP)
265 /*
266 * This BD is done and it's the last one, so return
267 * "done"
268 */
269 return 1;
270
271 bdp++;
272 }
273}
274
275/*
276 * Set the modem control lines
277 *
278 * Although the QE can control the modem control lines (e.g. CTS), we
279 * don't need that support. This function must exist, however, otherwise
280 * the kernel will panic.
281 */
282void qe_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
283{
284}
285
286/*
287 * Get the current modem control line status
288 *
289 * Although the QE can control the modem control lines (e.g. CTS), this
290 * driver currently doesn't support that, so we always return Carrier
291 * Detect, Data Set Ready, and Clear To Send.
292 */
293static unsigned int qe_uart_get_mctrl(struct uart_port *port)
294{
295 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
296}
297
298/*
299 * Disable the transmit interrupt.
300 *
301 * Although this function is called "stop_tx", it does not actually stop
302 * transmission of data. Instead, it tells the QE to not generate an
303 * interrupt when the UCC is finished sending characters.
304 */
305static void qe_uart_stop_tx(struct uart_port *port)
306{
307 struct uart_qe_port *qe_port =
308 container_of(port, struct uart_qe_port, port);
309
310 clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
311}
312
313/*
314 * Transmit as many characters to the HW as possible.
315 *
316 * This function will attempt to stuff of all the characters from the
317 * kernel's transmit buffer into TX BDs.
318 *
319 * A return value of non-zero indicates that it successfully stuffed all
320 * characters from the kernel buffer.
321 *
322 * A return value of zero indicates that there are still characters in the
323 * kernel's buffer that have not been transmitted, but there are no more BDs
324 * available. This function should be called again after a BD has been made
325 * available.
326 */
327static int qe_uart_tx_pump(struct uart_qe_port *qe_port)
328{
329 struct qe_bd *bdp;
330 unsigned char *p;
331 unsigned int count;
332 struct uart_port *port = &qe_port->port;
333 struct circ_buf *xmit = &port->state->xmit;
334
335 bdp = qe_port->rx_cur;
336
337 /* Handle xon/xoff */
338 if (port->x_char) {
339 /* Pick next descriptor and fill from buffer */
340 bdp = qe_port->tx_cur;
341
342 p = qe2cpu_addr(bdp->buf, qe_port);
343
344 *p++ = port->x_char;
345 out_be16(&bdp->length, 1);
346 setbits16(&bdp->status, BD_SC_READY);
347 /* Get next BD. */
348 if (in_be16(&bdp->status) & BD_SC_WRAP)
349 bdp = qe_port->tx_bd_base;
350 else
351 bdp++;
352 qe_port->tx_cur = bdp;
353
354 port->icount.tx++;
355 port->x_char = 0;
356 return 1;
357 }
358
359 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
360 qe_uart_stop_tx(port);
361 return 0;
362 }
363
364 /* Pick next descriptor and fill from buffer */
365 bdp = qe_port->tx_cur;
366
367 while (!(in_be16(&bdp->status) & BD_SC_READY) &&
368 (xmit->tail != xmit->head)) {
369 count = 0;
370 p = qe2cpu_addr(bdp->buf, qe_port);
371 while (count < qe_port->tx_fifosize) {
372 *p++ = xmit->buf[xmit->tail];
373 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
374 port->icount.tx++;
375 count++;
376 if (xmit->head == xmit->tail)
377 break;
378 }
379
380 out_be16(&bdp->length, count);
381 setbits16(&bdp->status, BD_SC_READY);
382
383 /* Get next BD. */
384 if (in_be16(&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 (in_be16(&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 setbits16(&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 clrbits16(&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 *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 = in_be16(&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 = in_be16(&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(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 clrsetbits_be16(&bdp->status, BD_SC_BR | BD_SC_FR | BD_SC_PR |
511 BD_SC_OV | BD_SC_ID, BD_SC_EMPTY);
512 if (in_be16(&bdp->status) & BD_SC_WRAP)
513 bdp = qe_port->rx_bd_base;
514 else
515 bdp++;
516
517 }
518
519 /* Write back buffer pointer */
520 qe_port->rx_cur = bdp;
521
522 /* Activate BH processing */
523 tty_flip_buffer_push(tport);
524
525 return;
526
527 /* Error processing */
528
529handle_error:
530 /* Statistics */
531 if (status & BD_SC_BR)
532 port->icount.brk++;
533 if (status & BD_SC_PR)
534 port->icount.parity++;
535 if (status & BD_SC_FR)
536 port->icount.frame++;
537 if (status & BD_SC_OV)
538 port->icount.overrun++;
539
540 /* Mask out ignored conditions */
541 status &= port->read_status_mask;
542
543 /* Handle the remaining ones */
544 if (status & BD_SC_BR)
545 flg = TTY_BREAK;
546 else if (status & BD_SC_PR)
547 flg = TTY_PARITY;
548 else if (status & BD_SC_FR)
549 flg = TTY_FRAME;
550
551 /* Overrun does not affect the current character ! */
552 if (status & BD_SC_OV)
553 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
554#ifdef SUPPORT_SYSRQ
555 port->sysrq = 0;
556#endif
557 goto error_return;
558}
559
560/* Interrupt handler
561 *
562 * This interrupt handler is called after a BD is processed.
563 */
564static irqreturn_t qe_uart_int(int irq, void *data)
565{
566 struct uart_qe_port *qe_port = (struct uart_qe_port *) data;
567 struct ucc_slow __iomem *uccp = qe_port->uccp;
568 u16 events;
569
570 /* Clear the interrupts */
571 events = in_be16(&uccp->ucce);
572 out_be16(&uccp->ucce, events);
573
574 if (events & UCC_UART_UCCE_BRKE)
575 uart_handle_break(&qe_port->port);
576
577 if (events & UCC_UART_UCCE_RX)
578 qe_uart_int_rx(qe_port);
579
580 if (events & UCC_UART_UCCE_TX)
581 qe_uart_tx_pump(qe_port);
582
583 return events ? IRQ_HANDLED : IRQ_NONE;
584}
585
586/* Initialize buffer descriptors
587 *
588 * This function initializes all of the RX and TX buffer descriptors.
589 */
590static void qe_uart_initbd(struct uart_qe_port *qe_port)
591{
592 int i;
593 void *bd_virt;
594 struct qe_bd *bdp;
595
596 /* Set the physical address of the host memory buffers in the buffer
597 * descriptors, and the virtual address for us to work with.
598 */
599 bd_virt = qe_port->bd_virt;
600 bdp = qe_port->rx_bd_base;
601 qe_port->rx_cur = qe_port->rx_bd_base;
602 for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) {
603 out_be16(&bdp->status, BD_SC_EMPTY | BD_SC_INTRPT);
604 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
605 out_be16(&bdp->length, 0);
606 bd_virt += qe_port->rx_fifosize;
607 bdp++;
608 }
609
610 /* */
611 out_be16(&bdp->status, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
612 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
613 out_be16(&bdp->length, 0);
614
615 /* Set the physical address of the host memory
616 * buffers in the buffer descriptors, and the
617 * virtual address for us to work with.
618 */
619 bd_virt = qe_port->bd_virt +
620 L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
621 qe_port->tx_cur = qe_port->tx_bd_base;
622 bdp = qe_port->tx_bd_base;
623 for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) {
624 out_be16(&bdp->status, BD_SC_INTRPT);
625 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
626 out_be16(&bdp->length, 0);
627 bd_virt += qe_port->tx_fifosize;
628 bdp++;
629 }
630
631 /* Loopback requires the preamble bit to be set on the first TX BD */
632#ifdef LOOPBACK
633 setbits16(&qe_port->tx_cur->status, BD_SC_P);
634#endif
635
636 out_be16(&bdp->status, BD_SC_WRAP | BD_SC_INTRPT);
637 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
638 out_be16(&bdp->length, 0);
639}
640
641/*
642 * Initialize a UCC for UART.
643 *
644 * This function configures a given UCC to be used as a UART device. Basic
645 * UCC initialization is handled in qe_uart_request_port(). This function
646 * does all the UART-specific stuff.
647 */
648static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
649{
650 u32 cecr_subblock;
651 struct ucc_slow __iomem *uccp = qe_port->uccp;
652 struct ucc_uart_pram *uccup = qe_port->uccup;
653
654 unsigned int i;
655
656 /* First, disable TX and RX in the UCC */
657 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
658
659 /* Program the UCC UART parameter RAM */
660 out_8(&uccup->common.rbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
661 out_8(&uccup->common.tbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
662 out_be16(&uccup->common.mrblr, qe_port->rx_fifosize);
663 out_be16(&uccup->maxidl, 0x10);
664 out_be16(&uccup->brkcr, 1);
665 out_be16(&uccup->parec, 0);
666 out_be16(&uccup->frmec, 0);
667 out_be16(&uccup->nosec, 0);
668 out_be16(&uccup->brkec, 0);
669 out_be16(&uccup->uaddr[0], 0);
670 out_be16(&uccup->uaddr[1], 0);
671 out_be16(&uccup->toseq, 0);
672 for (i = 0; i < 8; i++)
673 out_be16(&uccup->cchars[i], 0xC000);
674 out_be16(&uccup->rccm, 0xc0ff);
675
676 /* Configure the GUMR registers for UART */
677 if (soft_uart) {
678 /* Soft-UART requires a 1X multiplier for TX */
679 clrsetbits_be32(&uccp->gumr_l,
680 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
681 UCC_SLOW_GUMR_L_RDCR_MASK,
682 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 |
683 UCC_SLOW_GUMR_L_RDCR_16);
684
685 clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
686 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
687 } else {
688 clrsetbits_be32(&uccp->gumr_l,
689 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
690 UCC_SLOW_GUMR_L_RDCR_MASK,
691 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 |
692 UCC_SLOW_GUMR_L_RDCR_16);
693
694 clrsetbits_be32(&uccp->gumr_h,
695 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX,
696 UCC_SLOW_GUMR_H_RFW);
697 }
698
699#ifdef LOOPBACK
700 clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
701 UCC_SLOW_GUMR_L_DIAG_LOOP);
702 clrsetbits_be32(&uccp->gumr_h,
703 UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN,
704 UCC_SLOW_GUMR_H_CDS);
705#endif
706
707 /* Disable rx interrupts and clear all pending events. */
708 out_be16(&uccp->uccm, 0);
709 out_be16(&uccp->ucce, 0xffff);
710 out_be16(&uccp->udsr, 0x7e7e);
711
712 /* Initialize UPSMR */
713 out_be16(&uccp->upsmr, 0);
714
715 if (soft_uart) {
716 out_be16(&uccup->supsmr, 0x30);
717 out_be16(&uccup->res92, 0);
718 out_be32(&uccup->rx_state, 0);
719 out_be32(&uccup->rx_cnt, 0);
720 out_8(&uccup->rx_bitmark, 0);
721 out_8(&uccup->rx_length, 10);
722 out_be32(&uccup->dump_ptr, 0x4000);
723 out_8(&uccup->rx_temp_dlst_qe, 0);
724 out_be32(&uccup->rx_frame_rem, 0);
725 out_8(&uccup->rx_frame_rem_size, 0);
726 /* Soft-UART requires TX to be 1X */
727 out_8(&uccup->tx_mode,
728 UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1);
729 out_be16(&uccup->tx_state, 0);
730 out_8(&uccup->resD4, 0);
731 out_be16(&uccup->resD5, 0);
732
733 /* Set UART mode.
734 * Enable receive and transmit.
735 */
736
737 /* From the microcode errata:
738 * 1.GUMR_L register, set mode=0010 (QMC).
739 * 2.Set GUMR_H[17] bit. (UART/AHDLC mode).
740 * 3.Set GUMR_H[19:20] (Transparent mode)
741 * 4.Clear GUMR_H[26] (RFW)
742 * ...
743 * 6.Receiver must use 16x over sampling
744 */
745 clrsetbits_be32(&uccp->gumr_l,
746 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
747 UCC_SLOW_GUMR_L_RDCR_MASK,
748 UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 |
749 UCC_SLOW_GUMR_L_RDCR_16);
750
751 clrsetbits_be32(&uccp->gumr_h,
752 UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN,
753 UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX |
754 UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL);
755
756#ifdef LOOPBACK
757 clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
758 UCC_SLOW_GUMR_L_DIAG_LOOP);
759 clrbits32(&uccp->gumr_h, UCC_SLOW_GUMR_H_CTSP |
760 UCC_SLOW_GUMR_H_CDS);
761#endif
762
763 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
764 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
765 QE_CR_PROTOCOL_UNSPECIFIED, 0);
766 } else {
767 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
768 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
769 QE_CR_PROTOCOL_UART, 0);
770 }
771}
772
773/*
774 * Initialize the port.
775 */
776static int qe_uart_startup(struct uart_port *port)
777{
778 struct uart_qe_port *qe_port =
779 container_of(port, struct uart_qe_port, port);
780 int ret;
781
782 /*
783 * If we're using Soft-UART mode, then we need to make sure the
784 * firmware has been uploaded first.
785 */
786 if (soft_uart && !firmware_loaded) {
787 dev_err(port->dev, "Soft-UART firmware not uploaded\n");
788 return -ENODEV;
789 }
790
791 qe_uart_initbd(qe_port);
792 qe_uart_init_ucc(qe_port);
793
794 /* Install interrupt handler. */
795 ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart",
796 qe_port);
797 if (ret) {
798 dev_err(port->dev, "could not claim IRQ %u\n", port->irq);
799 return ret;
800 }
801
802 /* Startup rx-int */
803 setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
804 ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX);
805
806 return 0;
807}
808
809/*
810 * Shutdown the port.
811 */
812static void qe_uart_shutdown(struct uart_port *port)
813{
814 struct uart_qe_port *qe_port =
815 container_of(port, struct uart_qe_port, port);
816 struct ucc_slow __iomem *uccp = qe_port->uccp;
817 unsigned int timeout = 20;
818
819 /* Disable RX and TX */
820
821 /* Wait for all the BDs marked sent */
822 while (!qe_uart_tx_empty(port)) {
823 if (!--timeout) {
824 dev_warn(port->dev, "shutdown timeout\n");
825 break;
826 }
827 set_current_state(TASK_UNINTERRUPTIBLE);
828 schedule_timeout(2);
829 }
830
831 if (qe_port->wait_closing) {
832 /* Wait a bit longer */
833 set_current_state(TASK_UNINTERRUPTIBLE);
834 schedule_timeout(qe_port->wait_closing);
835 }
836
837 /* Stop uarts */
838 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
839 clrbits16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX);
840
841 /* Shut them really down and reinit buffer descriptors */
842 ucc_slow_graceful_stop_tx(qe_port->us_private);
843 qe_uart_initbd(qe_port);
844
845 free_irq(port->irq, qe_port);
846}
847
848/*
849 * Set the serial port parameters.
850 */
851static void qe_uart_set_termios(struct uart_port *port,
852 struct ktermios *termios, struct ktermios *old)
853{
854 struct uart_qe_port *qe_port =
855 container_of(port, struct uart_qe_port, port);
856 struct ucc_slow __iomem *uccp = qe_port->uccp;
857 unsigned int baud;
858 unsigned long flags;
859 u16 upsmr = in_be16(&uccp->upsmr);
860 struct ucc_uart_pram __iomem *uccup = qe_port->uccup;
861 u16 supsmr = in_be16(&uccup->supsmr);
862 u8 char_length = 2; /* 1 + CL + PEN + 1 + SL */
863
864 /* Character length programmed into the mode register is the
865 * sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
866 * 1 or 2 stop bits, minus 1.
867 * The value 'bits' counts this for us.
868 */
869
870 /* byte size */
871 upsmr &= UCC_UART_UPSMR_CL_MASK;
872 supsmr &= UCC_UART_SUPSMR_CL_MASK;
873
874 switch (termios->c_cflag & CSIZE) {
875 case CS5:
876 upsmr |= UCC_UART_UPSMR_CL_5;
877 supsmr |= UCC_UART_SUPSMR_CL_5;
878 char_length += 5;
879 break;
880 case CS6:
881 upsmr |= UCC_UART_UPSMR_CL_6;
882 supsmr |= UCC_UART_SUPSMR_CL_6;
883 char_length += 6;
884 break;
885 case CS7:
886 upsmr |= UCC_UART_UPSMR_CL_7;
887 supsmr |= UCC_UART_SUPSMR_CL_7;
888 char_length += 7;
889 break;
890 default: /* case CS8 */
891 upsmr |= UCC_UART_UPSMR_CL_8;
892 supsmr |= UCC_UART_SUPSMR_CL_8;
893 char_length += 8;
894 break;
895 }
896
897 /* If CSTOPB is set, we want two stop bits */
898 if (termios->c_cflag & CSTOPB) {
899 upsmr |= UCC_UART_UPSMR_SL;
900 supsmr |= UCC_UART_SUPSMR_SL;
901 char_length++; /* + SL */
902 }
903
904 if (termios->c_cflag & PARENB) {
905 upsmr |= UCC_UART_UPSMR_PEN;
906 supsmr |= UCC_UART_SUPSMR_PEN;
907 char_length++; /* + PEN */
908
909 if (!(termios->c_cflag & PARODD)) {
910 upsmr &= ~(UCC_UART_UPSMR_RPM_MASK |
911 UCC_UART_UPSMR_TPM_MASK);
912 upsmr |= UCC_UART_UPSMR_RPM_EVEN |
913 UCC_UART_UPSMR_TPM_EVEN;
914 supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK |
915 UCC_UART_SUPSMR_TPM_MASK);
916 supsmr |= UCC_UART_SUPSMR_RPM_EVEN |
917 UCC_UART_SUPSMR_TPM_EVEN;
918 }
919 }
920
921 /*
922 * Set up parity check flag
923 */
924 port->read_status_mask = BD_SC_EMPTY | BD_SC_OV;
925 if (termios->c_iflag & INPCK)
926 port->read_status_mask |= BD_SC_FR | BD_SC_PR;
927 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
928 port->read_status_mask |= BD_SC_BR;
929
930 /*
931 * Characters to ignore
932 */
933 port->ignore_status_mask = 0;
934 if (termios->c_iflag & IGNPAR)
935 port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
936 if (termios->c_iflag & IGNBRK) {
937 port->ignore_status_mask |= BD_SC_BR;
938 /*
939 * If we're ignore parity and break indicators, ignore
940 * overruns too. (For real raw support).
941 */
942 if (termios->c_iflag & IGNPAR)
943 port->ignore_status_mask |= BD_SC_OV;
944 }
945 /*
946 * !!! ignore all characters if CREAD is not set
947 */
948 if ((termios->c_cflag & CREAD) == 0)
949 port->read_status_mask &= ~BD_SC_EMPTY;
950
951 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
952
953 /* Do we really need a spinlock here? */
954 spin_lock_irqsave(&port->lock, flags);
955
956 /* Update the per-port timeout. */
957 uart_update_timeout(port, termios->c_cflag, baud);
958
959 out_be16(&uccp->upsmr, upsmr);
960 if (soft_uart) {
961 out_be16(&uccup->supsmr, supsmr);
962 out_8(&uccup->rx_length, char_length);
963
964 /* Soft-UART requires a 1X multiplier for TX */
965 qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
966 qe_setbrg(qe_port->us_info.tx_clock, baud, 1);
967 } else {
968 qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
969 qe_setbrg(qe_port->us_info.tx_clock, baud, 16);
970 }
971
972 spin_unlock_irqrestore(&port->lock, flags);
973}
974
975/*
976 * Return a pointer to a string that describes what kind of port this is.
977 */
978static const char *qe_uart_type(struct uart_port *port)
979{
980 return "QE";
981}
982
983/*
984 * Allocate any memory and I/O resources required by the port.
985 */
986static int qe_uart_request_port(struct uart_port *port)
987{
988 int ret;
989 struct uart_qe_port *qe_port =
990 container_of(port, struct uart_qe_port, port);
991 struct ucc_slow_info *us_info = &qe_port->us_info;
992 struct ucc_slow_private *uccs;
993 unsigned int rx_size, tx_size;
994 void *bd_virt;
995 dma_addr_t bd_dma_addr = 0;
996
997 ret = ucc_slow_init(us_info, &uccs);
998 if (ret) {
999 dev_err(port->dev, "could not initialize UCC%u\n",
1000 qe_port->ucc_num);
1001 return ret;
1002 }
1003
1004 qe_port->us_private = uccs;
1005 qe_port->uccp = uccs->us_regs;
1006 qe_port->uccup = (struct ucc_uart_pram *) uccs->us_pram;
1007 qe_port->rx_bd_base = uccs->rx_bd;
1008 qe_port->tx_bd_base = uccs->tx_bd;
1009
1010 /*
1011 * Allocate the transmit and receive data buffers.
1012 */
1013
1014 rx_size = L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
1015 tx_size = L1_CACHE_ALIGN(qe_port->tx_nrfifos * qe_port->tx_fifosize);
1016
1017 bd_virt = dma_alloc_coherent(port->dev, rx_size + tx_size, &bd_dma_addr,
1018 GFP_KERNEL);
1019 if (!bd_virt) {
1020 dev_err(port->dev, "could not allocate buffer descriptors\n");
1021 return -ENOMEM;
1022 }
1023
1024 qe_port->bd_virt = bd_virt;
1025 qe_port->bd_dma_addr = bd_dma_addr;
1026 qe_port->bd_size = rx_size + tx_size;
1027
1028 qe_port->rx_buf = bd_virt;
1029 qe_port->tx_buf = qe_port->rx_buf + rx_size;
1030
1031 return 0;
1032}
1033
1034/*
1035 * Configure the port.
1036 *
1037 * We say we're a CPM-type port because that's mostly true. Once the device
1038 * is configured, this driver operates almost identically to the CPM serial
1039 * driver.
1040 */
1041static void qe_uart_config_port(struct uart_port *port, int flags)
1042{
1043 if (flags & UART_CONFIG_TYPE) {
1044 port->type = PORT_CPM;
1045 qe_uart_request_port(port);
1046 }
1047}
1048
1049/*
1050 * Release any memory and I/O resources that were allocated in
1051 * qe_uart_request_port().
1052 */
1053static void qe_uart_release_port(struct uart_port *port)
1054{
1055 struct uart_qe_port *qe_port =
1056 container_of(port, struct uart_qe_port, port);
1057 struct ucc_slow_private *uccs = qe_port->us_private;
1058
1059 dma_free_coherent(port->dev, qe_port->bd_size, qe_port->bd_virt,
1060 qe_port->bd_dma_addr);
1061
1062 ucc_slow_free(uccs);
1063}
1064
1065/*
1066 * Verify that the data in serial_struct is suitable for this device.
1067 */
1068static int qe_uart_verify_port(struct uart_port *port,
1069 struct serial_struct *ser)
1070{
1071 if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
1072 return -EINVAL;
1073
1074 if (ser->irq < 0 || ser->irq >= nr_irqs)
1075 return -EINVAL;
1076
1077 if (ser->baud_base < 9600)
1078 return -EINVAL;
1079
1080 return 0;
1081}
1082/* UART operations
1083 *
1084 * Details on these functions can be found in Documentation/driver-api/serial/driver.rst
1085 */
1086static const struct uart_ops qe_uart_pops = {
1087 .tx_empty = qe_uart_tx_empty,
1088 .set_mctrl = qe_uart_set_mctrl,
1089 .get_mctrl = qe_uart_get_mctrl,
1090 .stop_tx = qe_uart_stop_tx,
1091 .start_tx = qe_uart_start_tx,
1092 .stop_rx = qe_uart_stop_rx,
1093 .break_ctl = qe_uart_break_ctl,
1094 .startup = qe_uart_startup,
1095 .shutdown = qe_uart_shutdown,
1096 .set_termios = qe_uart_set_termios,
1097 .type = qe_uart_type,
1098 .release_port = qe_uart_release_port,
1099 .request_port = qe_uart_request_port,
1100 .config_port = qe_uart_config_port,
1101 .verify_port = qe_uart_verify_port,
1102};
1103
1104/*
1105 * Obtain the SOC model number and revision level
1106 *
1107 * This function parses the device tree to obtain the SOC model. It then
1108 * reads the SVR register to the revision.
1109 *
1110 * The device tree stores the SOC model two different ways.
1111 *
1112 * The new way is:
1113 *
1114 * cpu@0 {
1115 * compatible = "PowerPC,8323";
1116 * device_type = "cpu";
1117 * ...
1118 *
1119 *
1120 * The old way is:
1121 * PowerPC,8323@0 {
1122 * device_type = "cpu";
1123 * ...
1124 *
1125 * This code first checks the new way, and then the old way.
1126 */
1127static unsigned int soc_info(unsigned int *rev_h, unsigned int *rev_l)
1128{
1129 struct device_node *np;
1130 const char *soc_string;
1131 unsigned int svr;
1132 unsigned int soc;
1133
1134 /* Find the CPU node */
1135 np = of_find_node_by_type(NULL, "cpu");
1136 if (!np)
1137 return 0;
1138 /* Find the compatible property */
1139 soc_string = of_get_property(np, "compatible", NULL);
1140 if (!soc_string)
1141 /* No compatible property, so try the name. */
1142 soc_string = np->name;
1143
1144 /* Extract the SOC number from the "PowerPC," string */
1145 if ((sscanf(soc_string, "PowerPC,%u", &soc) != 1) || !soc)
1146 return 0;
1147
1148 /* Get the revision from the SVR */
1149 svr = mfspr(SPRN_SVR);
1150 *rev_h = (svr >> 4) & 0xf;
1151 *rev_l = svr & 0xf;
1152
1153 return soc;
1154}
1155
1156/*
1157 * requst_firmware_nowait() callback function
1158 *
1159 * This function is called by the kernel when a firmware is made available,
1160 * or if it times out waiting for the firmware.
1161 */
1162static void uart_firmware_cont(const struct firmware *fw, void *context)
1163{
1164 struct qe_firmware *firmware;
1165 struct device *dev = context;
1166 int ret;
1167
1168 if (!fw) {
1169 dev_err(dev, "firmware not found\n");
1170 return;
1171 }
1172
1173 firmware = (struct qe_firmware *) fw->data;
1174
1175 if (firmware->header.length != fw->size) {
1176 dev_err(dev, "invalid firmware\n");
1177 goto out;
1178 }
1179
1180 ret = qe_upload_firmware(firmware);
1181 if (ret) {
1182 dev_err(dev, "could not load firmware\n");
1183 goto out;
1184 }
1185
1186 firmware_loaded = 1;
1187 out:
1188 release_firmware(fw);
1189}
1190
1191static int ucc_uart_probe(struct platform_device *ofdev)
1192{
1193 struct device_node *np = ofdev->dev.of_node;
1194 const unsigned int *iprop; /* Integer OF properties */
1195 const char *sprop; /* String OF properties */
1196 struct uart_qe_port *qe_port = NULL;
1197 struct resource res;
1198 int ret;
1199
1200 /*
1201 * Determine if we need Soft-UART mode
1202 */
1203 if (of_find_property(np, "soft-uart", NULL)) {
1204 dev_dbg(&ofdev->dev, "using Soft-UART mode\n");
1205 soft_uart = 1;
1206 }
1207
1208 /*
1209 * If we are using Soft-UART, determine if we need to upload the
1210 * firmware, too.
1211 */
1212 if (soft_uart) {
1213 struct qe_firmware_info *qe_fw_info;
1214
1215 qe_fw_info = qe_get_firmware_info();
1216
1217 /* Check if the firmware has been uploaded. */
1218 if (qe_fw_info && strstr(qe_fw_info->id, "Soft-UART")) {
1219 firmware_loaded = 1;
1220 } else {
1221 char filename[32];
1222 unsigned int soc;
1223 unsigned int rev_h;
1224 unsigned int rev_l;
1225
1226 soc = soc_info(&rev_h, &rev_l);
1227 if (!soc) {
1228 dev_err(&ofdev->dev, "unknown CPU model\n");
1229 return -ENXIO;
1230 }
1231 sprintf(filename, "fsl_qe_ucode_uart_%u_%u%u.bin",
1232 soc, rev_h, rev_l);
1233
1234 dev_info(&ofdev->dev, "waiting for firmware %s\n",
1235 filename);
1236
1237 /*
1238 * We call request_firmware_nowait instead of
1239 * request_firmware so that the driver can load and
1240 * initialize the ports without holding up the rest of
1241 * the kernel. If hotplug support is enabled in the
1242 * kernel, then we use it.
1243 */
1244 ret = request_firmware_nowait(THIS_MODULE,
1245 FW_ACTION_HOTPLUG, filename, &ofdev->dev,
1246 GFP_KERNEL, &ofdev->dev, uart_firmware_cont);
1247 if (ret) {
1248 dev_err(&ofdev->dev,
1249 "could not load firmware %s\n",
1250 filename);
1251 return ret;
1252 }
1253 }
1254 }
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 iprop = of_get_property(np, "cell-index", NULL);
1278 if (!iprop) {
1279 iprop = of_get_property(np, "device-id", NULL);
1280 if (!iprop) {
1281 dev_err(&ofdev->dev, "UCC is unspecified in "
1282 "device tree\n");
1283 ret = -EINVAL;
1284 goto out_free;
1285 }
1286 }
1287
1288 if ((*iprop < 1) || (*iprop > UCC_MAX_NUM)) {
1289 dev_err(&ofdev->dev, "no support for UCC%u\n", *iprop);
1290 ret = -ENODEV;
1291 goto out_free;
1292 }
1293 qe_port->ucc_num = *iprop - 1;
1294
1295 /*
1296 * In the future, we should not require the BRG to be specified in the
1297 * device tree. If no clock-source is specified, then just pick a BRG
1298 * to use. This requires a new QE library function that manages BRG
1299 * assignments.
1300 */
1301
1302 sprop = of_get_property(np, "rx-clock-name", NULL);
1303 if (!sprop) {
1304 dev_err(&ofdev->dev, "missing rx-clock-name in device tree\n");
1305 ret = -ENODEV;
1306 goto out_free;
1307 }
1308
1309 qe_port->us_info.rx_clock = qe_clock_source(sprop);
1310 if ((qe_port->us_info.rx_clock < QE_BRG1) ||
1311 (qe_port->us_info.rx_clock > QE_BRG16)) {
1312 dev_err(&ofdev->dev, "rx-clock-name must be a BRG for UART\n");
1313 ret = -ENODEV;
1314 goto out_free;
1315 }
1316
1317#ifdef LOOPBACK
1318 /* In internal loopback mode, TX and RX must use the same clock */
1319 qe_port->us_info.tx_clock = qe_port->us_info.rx_clock;
1320#else
1321 sprop = of_get_property(np, "tx-clock-name", NULL);
1322 if (!sprop) {
1323 dev_err(&ofdev->dev, "missing tx-clock-name in device tree\n");
1324 ret = -ENODEV;
1325 goto out_free;
1326 }
1327 qe_port->us_info.tx_clock = qe_clock_source(sprop);
1328#endif
1329 if ((qe_port->us_info.tx_clock < QE_BRG1) ||
1330 (qe_port->us_info.tx_clock > QE_BRG16)) {
1331 dev_err(&ofdev->dev, "tx-clock-name must be a BRG for UART\n");
1332 ret = -ENODEV;
1333 goto out_free;
1334 }
1335
1336 /* Get the port number, numbered 0-3 */
1337 iprop = of_get_property(np, "port-number", NULL);
1338 if (!iprop) {
1339 dev_err(&ofdev->dev, "missing port-number in device tree\n");
1340 ret = -EINVAL;
1341 goto out_free;
1342 }
1343 qe_port->port.line = *iprop;
1344 if (qe_port->port.line >= UCC_MAX_UART) {
1345 dev_err(&ofdev->dev, "port-number must be 0-%u\n",
1346 UCC_MAX_UART - 1);
1347 ret = -EINVAL;
1348 goto out_free;
1349 }
1350
1351 qe_port->port.irq = irq_of_parse_and_map(np, 0);
1352 if (qe_port->port.irq == 0) {
1353 dev_err(&ofdev->dev, "could not map IRQ for UCC%u\n",
1354 qe_port->ucc_num + 1);
1355 ret = -EINVAL;
1356 goto out_free;
1357 }
1358
1359 /*
1360 * Newer device trees have an "fsl,qe" compatible property for the QE
1361 * node, but we still need to support older device trees.
1362 */
1363 np = of_find_compatible_node(NULL, NULL, "fsl,qe");
1364 if (!np) {
1365 np = of_find_node_by_type(NULL, "qe");
1366 if (!np) {
1367 dev_err(&ofdev->dev, "could not find 'qe' node\n");
1368 ret = -EINVAL;
1369 goto out_free;
1370 }
1371 }
1372
1373 iprop = of_get_property(np, "brg-frequency", NULL);
1374 if (!iprop) {
1375 dev_err(&ofdev->dev,
1376 "missing brg-frequency in device tree\n");
1377 ret = -EINVAL;
1378 goto out_np;
1379 }
1380
1381 if (*iprop)
1382 qe_port->port.uartclk = *iprop;
1383 else {
1384 /*
1385 * Older versions of U-Boot do not initialize the brg-frequency
1386 * property, so in this case we assume the BRG frequency is
1387 * half the QE bus frequency.
1388 */
1389 iprop = of_get_property(np, "bus-frequency", NULL);
1390 if (!iprop) {
1391 dev_err(&ofdev->dev,
1392 "missing QE bus-frequency in device tree\n");
1393 ret = -EINVAL;
1394 goto out_np;
1395 }
1396 if (*iprop)
1397 qe_port->port.uartclk = *iprop / 2;
1398 else {
1399 dev_err(&ofdev->dev,
1400 "invalid QE bus-frequency in device tree\n");
1401 ret = -EINVAL;
1402 goto out_np;
1403 }
1404 }
1405
1406 spin_lock_init(&qe_port->port.lock);
1407 qe_port->np = np;
1408 qe_port->port.dev = &ofdev->dev;
1409 qe_port->port.ops = &qe_uart_pops;
1410 qe_port->port.iotype = UPIO_MEM;
1411
1412 qe_port->tx_nrfifos = TX_NUM_FIFO;
1413 qe_port->tx_fifosize = TX_BUF_SIZE;
1414 qe_port->rx_nrfifos = RX_NUM_FIFO;
1415 qe_port->rx_fifosize = RX_BUF_SIZE;
1416
1417 qe_port->wait_closing = UCC_WAIT_CLOSING;
1418 qe_port->port.fifosize = 512;
1419 qe_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
1420
1421 qe_port->us_info.ucc_num = qe_port->ucc_num;
1422 qe_port->us_info.regs = (phys_addr_t) res.start;
1423 qe_port->us_info.irq = qe_port->port.irq;
1424
1425 qe_port->us_info.rx_bd_ring_len = qe_port->rx_nrfifos;
1426 qe_port->us_info.tx_bd_ring_len = qe_port->tx_nrfifos;
1427
1428 /* Make sure ucc_slow_init() initializes both TX and RX */
1429 qe_port->us_info.init_tx = 1;
1430 qe_port->us_info.init_rx = 1;
1431
1432 /* Add the port to the uart sub-system. This will cause
1433 * qe_uart_config_port() to be called, so the us_info structure must
1434 * be initialized.
1435 */
1436 ret = uart_add_one_port(&ucc_uart_driver, &qe_port->port);
1437 if (ret) {
1438 dev_err(&ofdev->dev, "could not add /dev/ttyQE%u\n",
1439 qe_port->port.line);
1440 goto out_np;
1441 }
1442
1443 platform_set_drvdata(ofdev, qe_port);
1444
1445 dev_info(&ofdev->dev, "UCC%u assigned to /dev/ttyQE%u\n",
1446 qe_port->ucc_num + 1, qe_port->port.line);
1447
1448 /* Display the mknod command for this device */
1449 dev_dbg(&ofdev->dev, "mknod command is 'mknod /dev/ttyQE%u c %u %u'\n",
1450 qe_port->port.line, SERIAL_QE_MAJOR,
1451 SERIAL_QE_MINOR + qe_port->port.line);
1452
1453 return 0;
1454out_np:
1455 of_node_put(np);
1456out_free:
1457 kfree(qe_port);
1458 return ret;
1459}
1460
1461static int ucc_uart_remove(struct platform_device *ofdev)
1462{
1463 struct uart_qe_port *qe_port = platform_get_drvdata(ofdev);
1464
1465 dev_info(&ofdev->dev, "removing /dev/ttyQE%u\n", qe_port->port.line);
1466
1467 uart_remove_one_port(&ucc_uart_driver, &qe_port->port);
1468
1469 kfree(qe_port);
1470
1471 return 0;
1472}
1473
1474static const struct of_device_id ucc_uart_match[] = {
1475 {
1476 .type = "serial",
1477 .compatible = "ucc_uart",
1478 },
1479 {
1480 .compatible = "fsl,t1040-ucc-uart",
1481 },
1482 {},
1483};
1484MODULE_DEVICE_TABLE(of, ucc_uart_match);
1485
1486static struct platform_driver ucc_uart_of_driver = {
1487 .driver = {
1488 .name = "ucc_uart",
1489 .of_match_table = ucc_uart_match,
1490 },
1491 .probe = ucc_uart_probe,
1492 .remove = ucc_uart_remove,
1493};
1494
1495static int __init ucc_uart_init(void)
1496{
1497 int ret;
1498
1499 printk(KERN_INFO "Freescale QUICC Engine UART device driver\n");
1500#ifdef LOOPBACK
1501 printk(KERN_INFO "ucc-uart: Using loopback mode\n");
1502#endif
1503
1504 ret = uart_register_driver(&ucc_uart_driver);
1505 if (ret) {
1506 printk(KERN_ERR "ucc-uart: could not register UART driver\n");
1507 return ret;
1508 }
1509
1510 ret = platform_driver_register(&ucc_uart_of_driver);
1511 if (ret) {
1512 printk(KERN_ERR
1513 "ucc-uart: could not register platform driver\n");
1514 uart_unregister_driver(&ucc_uart_driver);
1515 }
1516
1517 return ret;
1518}
1519
1520static void __exit ucc_uart_exit(void)
1521{
1522 printk(KERN_INFO
1523 "Freescale QUICC Engine UART device driver unloading\n");
1524
1525 platform_driver_unregister(&ucc_uart_of_driver);
1526 uart_unregister_driver(&ucc_uart_driver);
1527}
1528
1529module_init(ucc_uart_init);
1530module_exit(ucc_uart_exit);
1531
1532MODULE_DESCRIPTION("Freescale QUICC Engine (QE) UART");
1533MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
1534MODULE_LICENSE("GPL v2");
1535MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_QE_MAJOR);
1536
1/*
2 * Freescale QUICC Engine UART device driver
3 *
4 * Author: Timur Tabi <timur@freescale.com>
5 *
6 * Copyright 2007 Freescale Semiconductor, Inc. This file is licensed under
7 * the terms of the GNU General Public License version 2. This program
8 * is licensed "as is" without any warranty of any kind, whether express
9 * or implied.
10 *
11 * This driver adds support for UART devices via Freescale's QUICC Engine
12 * found on some Freescale SOCs.
13 *
14 * If Soft-UART support is needed but not already present, then this driver
15 * will request and upload the "Soft-UART" microcode upon probe. The
16 * filename of the microcode should be fsl_qe_ucode_uart_X_YZ.bin, where "X"
17 * is the name of the SOC (e.g. 8323), and YZ is the revision of the SOC,
18 * (e.g. "11" for 1.1).
19 */
20
21#include <linux/module.h>
22#include <linux/serial.h>
23#include <linux/serial_core.h>
24#include <linux/slab.h>
25#include <linux/tty.h>
26#include <linux/tty_flip.h>
27#include <linux/io.h>
28#include <linux/of_address.h>
29#include <linux/of_irq.h>
30#include <linux/of_platform.h>
31#include <linux/dma-mapping.h>
32
33#include <linux/fs_uart_pd.h>
34#include <asm/ucc_slow.h>
35
36#include <linux/firmware.h>
37#include <asm/reg.h>
38
39/*
40 * The GUMR flag for Soft UART. This would normally be defined in qe.h,
41 * but Soft-UART is a hack and we want to keep everything related to it in
42 * this file.
43 */
44#define UCC_SLOW_GUMR_H_SUART 0x00004000 /* Soft-UART */
45
46/*
47 * soft_uart is 1 if we need to use Soft-UART mode
48 */
49static int soft_uart;
50/*
51 * firmware_loaded is 1 if the firmware has been loaded, 0 otherwise.
52 */
53static int firmware_loaded;
54
55/* Enable this macro to configure all serial ports in internal loopback
56 mode */
57/* #define LOOPBACK */
58
59/* The major and minor device numbers are defined in
60 * http://www.lanana.org/docs/device-list/devices-2.6+.txt. For the QE
61 * UART, we have major number 204 and minor numbers 46 - 49, which are the
62 * same as for the CPM2. This decision was made because no Freescale part
63 * has both a CPM and a QE.
64 */
65#define SERIAL_QE_MAJOR 204
66#define SERIAL_QE_MINOR 46
67
68/* Since we only have minor numbers 46 - 49, there is a hard limit of 4 ports */
69#define UCC_MAX_UART 4
70
71/* The number of buffer descriptors for receiving characters. */
72#define RX_NUM_FIFO 4
73
74/* The number of buffer descriptors for transmitting characters. */
75#define TX_NUM_FIFO 4
76
77/* The maximum size of the character buffer for a single RX BD. */
78#define RX_BUF_SIZE 32
79
80/* The maximum size of the character buffer for a single TX BD. */
81#define TX_BUF_SIZE 32
82
83/*
84 * The number of jiffies to wait after receiving a close command before the
85 * device is actually closed. This allows the last few characters to be
86 * sent over the wire.
87 */
88#define UCC_WAIT_CLOSING 100
89
90struct ucc_uart_pram {
91 struct ucc_slow_pram common;
92 u8 res1[8]; /* reserved */
93 __be16 maxidl; /* Maximum idle chars */
94 __be16 idlc; /* temp idle counter */
95 __be16 brkcr; /* Break count register */
96 __be16 parec; /* receive parity error counter */
97 __be16 frmec; /* receive framing error counter */
98 __be16 nosec; /* receive noise counter */
99 __be16 brkec; /* receive break condition counter */
100 __be16 brkln; /* last received break length */
101 __be16 uaddr[2]; /* UART address character 1 & 2 */
102 __be16 rtemp; /* Temp storage */
103 __be16 toseq; /* Transmit out of sequence char */
104 __be16 cchars[8]; /* control characters 1-8 */
105 __be16 rccm; /* receive control character mask */
106 __be16 rccr; /* receive control character register */
107 __be16 rlbc; /* receive last break character */
108 __be16 res2; /* reserved */
109 __be32 res3; /* reserved, should be cleared */
110 u8 res4; /* reserved, should be cleared */
111 u8 res5[3]; /* reserved, should be cleared */
112 __be32 res6; /* reserved, should be cleared */
113 __be32 res7; /* reserved, should be cleared */
114 __be32 res8; /* reserved, should be cleared */
115 __be32 res9; /* reserved, should be cleared */
116 __be32 res10; /* reserved, should be cleared */
117 __be32 res11; /* reserved, should be cleared */
118 __be32 res12; /* reserved, should be cleared */
119 __be32 res13; /* reserved, should be cleared */
120/* The rest is for Soft-UART only */
121 __be16 supsmr; /* 0x90, Shadow UPSMR */
122 __be16 res92; /* 0x92, reserved, initialize to 0 */
123 __be32 rx_state; /* 0x94, RX state, initialize to 0 */
124 __be32 rx_cnt; /* 0x98, RX count, initialize to 0 */
125 u8 rx_length; /* 0x9C, Char length, set to 1+CL+PEN+1+SL */
126 u8 rx_bitmark; /* 0x9D, reserved, initialize to 0 */
127 u8 rx_temp_dlst_qe; /* 0x9E, reserved, initialize to 0 */
128 u8 res14[0xBC - 0x9F]; /* reserved */
129 __be32 dump_ptr; /* 0xBC, Dump pointer */
130 __be32 rx_frame_rem; /* 0xC0, reserved, initialize to 0 */
131 u8 rx_frame_rem_size; /* 0xC4, reserved, initialize to 0 */
132 u8 tx_mode; /* 0xC5, mode, 0=AHDLC, 1=UART */
133 __be16 tx_state; /* 0xC6, TX state */
134 u8 res15[0xD0 - 0xC8]; /* reserved */
135 __be32 resD0; /* 0xD0, reserved, initialize to 0 */
136 u8 resD4; /* 0xD4, reserved, initialize to 0 */
137 __be16 resD5; /* 0xD5, reserved, initialize to 0 */
138} __attribute__ ((packed));
139
140/* SUPSMR definitions, for Soft-UART only */
141#define UCC_UART_SUPSMR_SL 0x8000
142#define UCC_UART_SUPSMR_RPM_MASK 0x6000
143#define UCC_UART_SUPSMR_RPM_ODD 0x0000
144#define UCC_UART_SUPSMR_RPM_LOW 0x2000
145#define UCC_UART_SUPSMR_RPM_EVEN 0x4000
146#define UCC_UART_SUPSMR_RPM_HIGH 0x6000
147#define UCC_UART_SUPSMR_PEN 0x1000
148#define UCC_UART_SUPSMR_TPM_MASK 0x0C00
149#define UCC_UART_SUPSMR_TPM_ODD 0x0000
150#define UCC_UART_SUPSMR_TPM_LOW 0x0400
151#define UCC_UART_SUPSMR_TPM_EVEN 0x0800
152#define UCC_UART_SUPSMR_TPM_HIGH 0x0C00
153#define UCC_UART_SUPSMR_FRZ 0x0100
154#define UCC_UART_SUPSMR_UM_MASK 0x00c0
155#define UCC_UART_SUPSMR_UM_NORMAL 0x0000
156#define UCC_UART_SUPSMR_UM_MAN_MULTI 0x0040
157#define UCC_UART_SUPSMR_UM_AUTO_MULTI 0x00c0
158#define UCC_UART_SUPSMR_CL_MASK 0x0030
159#define UCC_UART_SUPSMR_CL_8 0x0030
160#define UCC_UART_SUPSMR_CL_7 0x0020
161#define UCC_UART_SUPSMR_CL_6 0x0010
162#define UCC_UART_SUPSMR_CL_5 0x0000
163
164#define UCC_UART_TX_STATE_AHDLC 0x00
165#define UCC_UART_TX_STATE_UART 0x01
166#define UCC_UART_TX_STATE_X1 0x00
167#define UCC_UART_TX_STATE_X16 0x80
168
169#define UCC_UART_PRAM_ALIGNMENT 0x100
170
171#define UCC_UART_SIZE_OF_BD UCC_SLOW_SIZE_OF_BD
172#define NUM_CONTROL_CHARS 8
173
174/* Private per-port data structure */
175struct uart_qe_port {
176 struct uart_port port;
177 struct ucc_slow __iomem *uccp;
178 struct ucc_uart_pram __iomem *uccup;
179 struct ucc_slow_info us_info;
180 struct ucc_slow_private *us_private;
181 struct device_node *np;
182 unsigned int ucc_num; /* First ucc is 0, not 1 */
183
184 u16 rx_nrfifos;
185 u16 rx_fifosize;
186 u16 tx_nrfifos;
187 u16 tx_fifosize;
188 int wait_closing;
189 u32 flags;
190 struct qe_bd *rx_bd_base;
191 struct qe_bd *rx_cur;
192 struct qe_bd *tx_bd_base;
193 struct qe_bd *tx_cur;
194 unsigned char *tx_buf;
195 unsigned char *rx_buf;
196 void *bd_virt; /* virtual address of the BD buffers */
197 dma_addr_t bd_dma_addr; /* bus address of the BD buffers */
198 unsigned int bd_size; /* size of BD buffer space */
199};
200
201static struct uart_driver ucc_uart_driver = {
202 .owner = THIS_MODULE,
203 .driver_name = "ucc_uart",
204 .dev_name = "ttyQE",
205 .major = SERIAL_QE_MAJOR,
206 .minor = SERIAL_QE_MINOR,
207 .nr = UCC_MAX_UART,
208};
209
210/*
211 * Virtual to physical address translation.
212 *
213 * Given the virtual address for a character buffer, this function returns
214 * the physical (DMA) equivalent.
215 */
216static inline dma_addr_t cpu2qe_addr(void *addr, struct uart_qe_port *qe_port)
217{
218 if (likely((addr >= qe_port->bd_virt)) &&
219 (addr < (qe_port->bd_virt + qe_port->bd_size)))
220 return qe_port->bd_dma_addr + (addr - qe_port->bd_virt);
221
222 /* something nasty happened */
223 printk(KERN_ERR "%s: addr=%p\n", __func__, addr);
224 BUG();
225 return 0;
226}
227
228/*
229 * Physical to virtual address translation.
230 *
231 * Given the physical (DMA) address for a character buffer, this function
232 * returns the virtual equivalent.
233 */
234static inline void *qe2cpu_addr(dma_addr_t addr, struct uart_qe_port *qe_port)
235{
236 /* sanity check */
237 if (likely((addr >= qe_port->bd_dma_addr) &&
238 (addr < (qe_port->bd_dma_addr + qe_port->bd_size))))
239 return qe_port->bd_virt + (addr - qe_port->bd_dma_addr);
240
241 /* something nasty happened */
242 printk(KERN_ERR "%s: addr=%llx\n", __func__, (u64)addr);
243 BUG();
244 return NULL;
245}
246
247/*
248 * Return 1 if the QE is done transmitting all buffers for this port
249 *
250 * This function scans each BD in sequence. If we find a BD that is not
251 * ready (READY=1), then we return 0 indicating that the QE is still sending
252 * data. If we reach the last BD (WRAP=1), then we know we've scanned
253 * the entire list, and all BDs are done.
254 */
255static unsigned int qe_uart_tx_empty(struct uart_port *port)
256{
257 struct uart_qe_port *qe_port =
258 container_of(port, struct uart_qe_port, port);
259 struct qe_bd *bdp = qe_port->tx_bd_base;
260
261 while (1) {
262 if (in_be16(&bdp->status) & BD_SC_READY)
263 /* This BD is not done, so return "not done" */
264 return 0;
265
266 if (in_be16(&bdp->status) & BD_SC_WRAP)
267 /*
268 * This BD is done and it's the last one, so return
269 * "done"
270 */
271 return 1;
272
273 bdp++;
274 }
275}
276
277/*
278 * Set the modem control lines
279 *
280 * Although the QE can control the modem control lines (e.g. CTS), we
281 * don't need that support. This function must exist, however, otherwise
282 * the kernel will panic.
283 */
284void qe_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
285{
286}
287
288/*
289 * Get the current modem control line status
290 *
291 * Although the QE can control the modem control lines (e.g. CTS), this
292 * driver currently doesn't support that, so we always return Carrier
293 * Detect, Data Set Ready, and Clear To Send.
294 */
295static unsigned int qe_uart_get_mctrl(struct uart_port *port)
296{
297 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
298}
299
300/*
301 * Disable the transmit interrupt.
302 *
303 * Although this function is called "stop_tx", it does not actually stop
304 * transmission of data. Instead, it tells the QE to not generate an
305 * interrupt when the UCC is finished sending characters.
306 */
307static void qe_uart_stop_tx(struct uart_port *port)
308{
309 struct uart_qe_port *qe_port =
310 container_of(port, struct uart_qe_port, port);
311
312 clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
313}
314
315/*
316 * Transmit as many characters to the HW as possible.
317 *
318 * This function will attempt to stuff of all the characters from the
319 * kernel's transmit buffer into TX BDs.
320 *
321 * A return value of non-zero indicates that it successfully stuffed all
322 * characters from the kernel buffer.
323 *
324 * A return value of zero indicates that there are still characters in the
325 * kernel's buffer that have not been transmitted, but there are no more BDs
326 * available. This function should be called again after a BD has been made
327 * available.
328 */
329static int qe_uart_tx_pump(struct uart_qe_port *qe_port)
330{
331 struct qe_bd *bdp;
332 unsigned char *p;
333 unsigned int count;
334 struct uart_port *port = &qe_port->port;
335 struct circ_buf *xmit = &port->state->xmit;
336
337 bdp = qe_port->rx_cur;
338
339 /* Handle xon/xoff */
340 if (port->x_char) {
341 /* Pick next descriptor and fill from buffer */
342 bdp = qe_port->tx_cur;
343
344 p = qe2cpu_addr(bdp->buf, qe_port);
345
346 *p++ = port->x_char;
347 out_be16(&bdp->length, 1);
348 setbits16(&bdp->status, BD_SC_READY);
349 /* Get next BD. */
350 if (in_be16(&bdp->status) & BD_SC_WRAP)
351 bdp = qe_port->tx_bd_base;
352 else
353 bdp++;
354 qe_port->tx_cur = bdp;
355
356 port->icount.tx++;
357 port->x_char = 0;
358 return 1;
359 }
360
361 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
362 qe_uart_stop_tx(port);
363 return 0;
364 }
365
366 /* Pick next descriptor and fill from buffer */
367 bdp = qe_port->tx_cur;
368
369 while (!(in_be16(&bdp->status) & BD_SC_READY) &&
370 (xmit->tail != xmit->head)) {
371 count = 0;
372 p = qe2cpu_addr(bdp->buf, qe_port);
373 while (count < qe_port->tx_fifosize) {
374 *p++ = xmit->buf[xmit->tail];
375 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
376 port->icount.tx++;
377 count++;
378 if (xmit->head == xmit->tail)
379 break;
380 }
381
382 out_be16(&bdp->length, count);
383 setbits16(&bdp->status, BD_SC_READY);
384
385 /* Get next BD. */
386 if (in_be16(&bdp->status) & BD_SC_WRAP)
387 bdp = qe_port->tx_bd_base;
388 else
389 bdp++;
390 }
391 qe_port->tx_cur = bdp;
392
393 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
394 uart_write_wakeup(port);
395
396 if (uart_circ_empty(xmit)) {
397 /* The kernel buffer is empty, so turn off TX interrupts. We
398 don't need to be told when the QE is finished transmitting
399 the data. */
400 qe_uart_stop_tx(port);
401 return 0;
402 }
403
404 return 1;
405}
406
407/*
408 * Start transmitting data
409 *
410 * This function will start transmitting any available data, if the port
411 * isn't already transmitting data.
412 */
413static void qe_uart_start_tx(struct uart_port *port)
414{
415 struct uart_qe_port *qe_port =
416 container_of(port, struct uart_qe_port, port);
417
418 /* If we currently are transmitting, then just return */
419 if (in_be16(&qe_port->uccp->uccm) & UCC_UART_UCCE_TX)
420 return;
421
422 /* Otherwise, pump the port and start transmission */
423 if (qe_uart_tx_pump(qe_port))
424 setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_TX);
425}
426
427/*
428 * Stop transmitting data
429 */
430static void qe_uart_stop_rx(struct uart_port *port)
431{
432 struct uart_qe_port *qe_port =
433 container_of(port, struct uart_qe_port, port);
434
435 clrbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
436}
437
438/*
439 * Enable status change interrupts
440 *
441 * We don't support status change interrupts, but we need to define this
442 * function otherwise the kernel will panic.
443 */
444static void qe_uart_enable_ms(struct uart_port *port)
445{
446}
447
448/* Start or stop sending break signal
449 *
450 * This function controls the sending of a break signal. If break_state=1,
451 * then we start sending a break signal. If break_state=0, then we stop
452 * sending the break signal.
453 */
454static void qe_uart_break_ctl(struct uart_port *port, int break_state)
455{
456 struct uart_qe_port *qe_port =
457 container_of(port, struct uart_qe_port, port);
458
459 if (break_state)
460 ucc_slow_stop_tx(qe_port->us_private);
461 else
462 ucc_slow_restart_tx(qe_port->us_private);
463}
464
465/* ISR helper function for receiving character.
466 *
467 * This function is called by the ISR to handling receiving characters
468 */
469static void qe_uart_int_rx(struct uart_qe_port *qe_port)
470{
471 int i;
472 unsigned char ch, *cp;
473 struct uart_port *port = &qe_port->port;
474 struct tty_port *tport = &port->state->port;
475 struct qe_bd *bdp;
476 u16 status;
477 unsigned int flg;
478
479 /* Just loop through the closed BDs and copy the characters into
480 * the buffer.
481 */
482 bdp = qe_port->rx_cur;
483 while (1) {
484 status = in_be16(&bdp->status);
485
486 /* If this one is empty, then we assume we've read them all */
487 if (status & BD_SC_EMPTY)
488 break;
489
490 /* get number of characters, and check space in RX buffer */
491 i = in_be16(&bdp->length);
492
493 /* If we don't have enough room in RX buffer for the entire BD,
494 * then we try later, which will be the next RX interrupt.
495 */
496 if (tty_buffer_request_room(tport, i) < i) {
497 dev_dbg(port->dev, "ucc-uart: no room in RX buffer\n");
498 return;
499 }
500
501 /* get pointer */
502 cp = qe2cpu_addr(bdp->buf, qe_port);
503
504 /* loop through the buffer */
505 while (i-- > 0) {
506 ch = *cp++;
507 port->icount.rx++;
508 flg = TTY_NORMAL;
509
510 if (!i && status &
511 (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
512 goto handle_error;
513 if (uart_handle_sysrq_char(port, ch))
514 continue;
515
516error_return:
517 tty_insert_flip_char(tport, ch, flg);
518
519 }
520
521 /* This BD is ready to be used again. Clear status. get next */
522 clrsetbits_be16(&bdp->status, BD_SC_BR | BD_SC_FR | BD_SC_PR |
523 BD_SC_OV | BD_SC_ID, BD_SC_EMPTY);
524 if (in_be16(&bdp->status) & BD_SC_WRAP)
525 bdp = qe_port->rx_bd_base;
526 else
527 bdp++;
528
529 }
530
531 /* Write back buffer pointer */
532 qe_port->rx_cur = bdp;
533
534 /* Activate BH processing */
535 tty_flip_buffer_push(tport);
536
537 return;
538
539 /* Error processing */
540
541handle_error:
542 /* Statistics */
543 if (status & BD_SC_BR)
544 port->icount.brk++;
545 if (status & BD_SC_PR)
546 port->icount.parity++;
547 if (status & BD_SC_FR)
548 port->icount.frame++;
549 if (status & BD_SC_OV)
550 port->icount.overrun++;
551
552 /* Mask out ignored conditions */
553 status &= port->read_status_mask;
554
555 /* Handle the remaining ones */
556 if (status & BD_SC_BR)
557 flg = TTY_BREAK;
558 else if (status & BD_SC_PR)
559 flg = TTY_PARITY;
560 else if (status & BD_SC_FR)
561 flg = TTY_FRAME;
562
563 /* Overrun does not affect the current character ! */
564 if (status & BD_SC_OV)
565 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
566#ifdef SUPPORT_SYSRQ
567 port->sysrq = 0;
568#endif
569 goto error_return;
570}
571
572/* Interrupt handler
573 *
574 * This interrupt handler is called after a BD is processed.
575 */
576static irqreturn_t qe_uart_int(int irq, void *data)
577{
578 struct uart_qe_port *qe_port = (struct uart_qe_port *) data;
579 struct ucc_slow __iomem *uccp = qe_port->uccp;
580 u16 events;
581
582 /* Clear the interrupts */
583 events = in_be16(&uccp->ucce);
584 out_be16(&uccp->ucce, events);
585
586 if (events & UCC_UART_UCCE_BRKE)
587 uart_handle_break(&qe_port->port);
588
589 if (events & UCC_UART_UCCE_RX)
590 qe_uart_int_rx(qe_port);
591
592 if (events & UCC_UART_UCCE_TX)
593 qe_uart_tx_pump(qe_port);
594
595 return events ? IRQ_HANDLED : IRQ_NONE;
596}
597
598/* Initialize buffer descriptors
599 *
600 * This function initializes all of the RX and TX buffer descriptors.
601 */
602static void qe_uart_initbd(struct uart_qe_port *qe_port)
603{
604 int i;
605 void *bd_virt;
606 struct qe_bd *bdp;
607
608 /* Set the physical address of the host memory buffers in the buffer
609 * descriptors, and the virtual address for us to work with.
610 */
611 bd_virt = qe_port->bd_virt;
612 bdp = qe_port->rx_bd_base;
613 qe_port->rx_cur = qe_port->rx_bd_base;
614 for (i = 0; i < (qe_port->rx_nrfifos - 1); i++) {
615 out_be16(&bdp->status, BD_SC_EMPTY | BD_SC_INTRPT);
616 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
617 out_be16(&bdp->length, 0);
618 bd_virt += qe_port->rx_fifosize;
619 bdp++;
620 }
621
622 /* */
623 out_be16(&bdp->status, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
624 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
625 out_be16(&bdp->length, 0);
626
627 /* Set the physical address of the host memory
628 * buffers in the buffer descriptors, and the
629 * virtual address for us to work with.
630 */
631 bd_virt = qe_port->bd_virt +
632 L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
633 qe_port->tx_cur = qe_port->tx_bd_base;
634 bdp = qe_port->tx_bd_base;
635 for (i = 0; i < (qe_port->tx_nrfifos - 1); i++) {
636 out_be16(&bdp->status, BD_SC_INTRPT);
637 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
638 out_be16(&bdp->length, 0);
639 bd_virt += qe_port->tx_fifosize;
640 bdp++;
641 }
642
643 /* Loopback requires the preamble bit to be set on the first TX BD */
644#ifdef LOOPBACK
645 setbits16(&qe_port->tx_cur->status, BD_SC_P);
646#endif
647
648 out_be16(&bdp->status, BD_SC_WRAP | BD_SC_INTRPT);
649 out_be32(&bdp->buf, cpu2qe_addr(bd_virt, qe_port));
650 out_be16(&bdp->length, 0);
651}
652
653/*
654 * Initialize a UCC for UART.
655 *
656 * This function configures a given UCC to be used as a UART device. Basic
657 * UCC initialization is handled in qe_uart_request_port(). This function
658 * does all the UART-specific stuff.
659 */
660static void qe_uart_init_ucc(struct uart_qe_port *qe_port)
661{
662 u32 cecr_subblock;
663 struct ucc_slow __iomem *uccp = qe_port->uccp;
664 struct ucc_uart_pram *uccup = qe_port->uccup;
665
666 unsigned int i;
667
668 /* First, disable TX and RX in the UCC */
669 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
670
671 /* Program the UCC UART parameter RAM */
672 out_8(&uccup->common.rbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
673 out_8(&uccup->common.tbmr, UCC_BMR_GBL | UCC_BMR_BO_BE);
674 out_be16(&uccup->common.mrblr, qe_port->rx_fifosize);
675 out_be16(&uccup->maxidl, 0x10);
676 out_be16(&uccup->brkcr, 1);
677 out_be16(&uccup->parec, 0);
678 out_be16(&uccup->frmec, 0);
679 out_be16(&uccup->nosec, 0);
680 out_be16(&uccup->brkec, 0);
681 out_be16(&uccup->uaddr[0], 0);
682 out_be16(&uccup->uaddr[1], 0);
683 out_be16(&uccup->toseq, 0);
684 for (i = 0; i < 8; i++)
685 out_be16(&uccup->cchars[i], 0xC000);
686 out_be16(&uccup->rccm, 0xc0ff);
687
688 /* Configure the GUMR registers for UART */
689 if (soft_uart) {
690 /* Soft-UART requires a 1X multiplier for TX */
691 clrsetbits_be32(&uccp->gumr_l,
692 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
693 UCC_SLOW_GUMR_L_RDCR_MASK,
694 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_1 |
695 UCC_SLOW_GUMR_L_RDCR_16);
696
697 clrsetbits_be32(&uccp->gumr_h, UCC_SLOW_GUMR_H_RFW,
698 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX);
699 } else {
700 clrsetbits_be32(&uccp->gumr_l,
701 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
702 UCC_SLOW_GUMR_L_RDCR_MASK,
703 UCC_SLOW_GUMR_L_MODE_UART | UCC_SLOW_GUMR_L_TDCR_16 |
704 UCC_SLOW_GUMR_L_RDCR_16);
705
706 clrsetbits_be32(&uccp->gumr_h,
707 UCC_SLOW_GUMR_H_TRX | UCC_SLOW_GUMR_H_TTX,
708 UCC_SLOW_GUMR_H_RFW);
709 }
710
711#ifdef LOOPBACK
712 clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
713 UCC_SLOW_GUMR_L_DIAG_LOOP);
714 clrsetbits_be32(&uccp->gumr_h,
715 UCC_SLOW_GUMR_H_CTSP | UCC_SLOW_GUMR_H_RSYN,
716 UCC_SLOW_GUMR_H_CDS);
717#endif
718
719 /* Disable rx interrupts and clear all pending events. */
720 out_be16(&uccp->uccm, 0);
721 out_be16(&uccp->ucce, 0xffff);
722 out_be16(&uccp->udsr, 0x7e7e);
723
724 /* Initialize UPSMR */
725 out_be16(&uccp->upsmr, 0);
726
727 if (soft_uart) {
728 out_be16(&uccup->supsmr, 0x30);
729 out_be16(&uccup->res92, 0);
730 out_be32(&uccup->rx_state, 0);
731 out_be32(&uccup->rx_cnt, 0);
732 out_8(&uccup->rx_bitmark, 0);
733 out_8(&uccup->rx_length, 10);
734 out_be32(&uccup->dump_ptr, 0x4000);
735 out_8(&uccup->rx_temp_dlst_qe, 0);
736 out_be32(&uccup->rx_frame_rem, 0);
737 out_8(&uccup->rx_frame_rem_size, 0);
738 /* Soft-UART requires TX to be 1X */
739 out_8(&uccup->tx_mode,
740 UCC_UART_TX_STATE_UART | UCC_UART_TX_STATE_X1);
741 out_be16(&uccup->tx_state, 0);
742 out_8(&uccup->resD4, 0);
743 out_be16(&uccup->resD5, 0);
744
745 /* Set UART mode.
746 * Enable receive and transmit.
747 */
748
749 /* From the microcode errata:
750 * 1.GUMR_L register, set mode=0010 (QMC).
751 * 2.Set GUMR_H[17] bit. (UART/AHDLC mode).
752 * 3.Set GUMR_H[19:20] (Transparent mode)
753 * 4.Clear GUMR_H[26] (RFW)
754 * ...
755 * 6.Receiver must use 16x over sampling
756 */
757 clrsetbits_be32(&uccp->gumr_l,
758 UCC_SLOW_GUMR_L_MODE_MASK | UCC_SLOW_GUMR_L_TDCR_MASK |
759 UCC_SLOW_GUMR_L_RDCR_MASK,
760 UCC_SLOW_GUMR_L_MODE_QMC | UCC_SLOW_GUMR_L_TDCR_16 |
761 UCC_SLOW_GUMR_L_RDCR_16);
762
763 clrsetbits_be32(&uccp->gumr_h,
764 UCC_SLOW_GUMR_H_RFW | UCC_SLOW_GUMR_H_RSYN,
765 UCC_SLOW_GUMR_H_SUART | UCC_SLOW_GUMR_H_TRX |
766 UCC_SLOW_GUMR_H_TTX | UCC_SLOW_GUMR_H_TFL);
767
768#ifdef LOOPBACK
769 clrsetbits_be32(&uccp->gumr_l, UCC_SLOW_GUMR_L_DIAG_MASK,
770 UCC_SLOW_GUMR_L_DIAG_LOOP);
771 clrbits32(&uccp->gumr_h, UCC_SLOW_GUMR_H_CTSP |
772 UCC_SLOW_GUMR_H_CDS);
773#endif
774
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_UNSPECIFIED, 0);
778 } else {
779 cecr_subblock = ucc_slow_get_qe_cr_subblock(qe_port->ucc_num);
780 qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
781 QE_CR_PROTOCOL_UART, 0);
782 }
783}
784
785/*
786 * Initialize the port.
787 */
788static int qe_uart_startup(struct uart_port *port)
789{
790 struct uart_qe_port *qe_port =
791 container_of(port, struct uart_qe_port, port);
792 int ret;
793
794 /*
795 * If we're using Soft-UART mode, then we need to make sure the
796 * firmware has been uploaded first.
797 */
798 if (soft_uart && !firmware_loaded) {
799 dev_err(port->dev, "Soft-UART firmware not uploaded\n");
800 return -ENODEV;
801 }
802
803 qe_uart_initbd(qe_port);
804 qe_uart_init_ucc(qe_port);
805
806 /* Install interrupt handler. */
807 ret = request_irq(port->irq, qe_uart_int, IRQF_SHARED, "ucc-uart",
808 qe_port);
809 if (ret) {
810 dev_err(port->dev, "could not claim IRQ %u\n", port->irq);
811 return ret;
812 }
813
814 /* Startup rx-int */
815 setbits16(&qe_port->uccp->uccm, UCC_UART_UCCE_RX);
816 ucc_slow_enable(qe_port->us_private, COMM_DIR_RX_AND_TX);
817
818 return 0;
819}
820
821/*
822 * Shutdown the port.
823 */
824static void qe_uart_shutdown(struct uart_port *port)
825{
826 struct uart_qe_port *qe_port =
827 container_of(port, struct uart_qe_port, port);
828 struct ucc_slow __iomem *uccp = qe_port->uccp;
829 unsigned int timeout = 20;
830
831 /* Disable RX and TX */
832
833 /* Wait for all the BDs marked sent */
834 while (!qe_uart_tx_empty(port)) {
835 if (!--timeout) {
836 dev_warn(port->dev, "shutdown timeout\n");
837 break;
838 }
839 set_current_state(TASK_UNINTERRUPTIBLE);
840 schedule_timeout(2);
841 }
842
843 if (qe_port->wait_closing) {
844 /* Wait a bit longer */
845 set_current_state(TASK_UNINTERRUPTIBLE);
846 schedule_timeout(qe_port->wait_closing);
847 }
848
849 /* Stop uarts */
850 ucc_slow_disable(qe_port->us_private, COMM_DIR_RX_AND_TX);
851 clrbits16(&uccp->uccm, UCC_UART_UCCE_TX | UCC_UART_UCCE_RX);
852
853 /* Shut them really down and reinit buffer descriptors */
854 ucc_slow_graceful_stop_tx(qe_port->us_private);
855 qe_uart_initbd(qe_port);
856
857 free_irq(port->irq, qe_port);
858}
859
860/*
861 * Set the serial port parameters.
862 */
863static void qe_uart_set_termios(struct uart_port *port,
864 struct ktermios *termios, struct ktermios *old)
865{
866 struct uart_qe_port *qe_port =
867 container_of(port, struct uart_qe_port, port);
868 struct ucc_slow __iomem *uccp = qe_port->uccp;
869 unsigned int baud;
870 unsigned long flags;
871 u16 upsmr = in_be16(&uccp->upsmr);
872 struct ucc_uart_pram __iomem *uccup = qe_port->uccup;
873 u16 supsmr = in_be16(&uccup->supsmr);
874 u8 char_length = 2; /* 1 + CL + PEN + 1 + SL */
875
876 /* Character length programmed into the mode register is the
877 * sum of: 1 start bit, number of data bits, 0 or 1 parity bit,
878 * 1 or 2 stop bits, minus 1.
879 * The value 'bits' counts this for us.
880 */
881
882 /* byte size */
883 upsmr &= UCC_UART_UPSMR_CL_MASK;
884 supsmr &= UCC_UART_SUPSMR_CL_MASK;
885
886 switch (termios->c_cflag & CSIZE) {
887 case CS5:
888 upsmr |= UCC_UART_UPSMR_CL_5;
889 supsmr |= UCC_UART_SUPSMR_CL_5;
890 char_length += 5;
891 break;
892 case CS6:
893 upsmr |= UCC_UART_UPSMR_CL_6;
894 supsmr |= UCC_UART_SUPSMR_CL_6;
895 char_length += 6;
896 break;
897 case CS7:
898 upsmr |= UCC_UART_UPSMR_CL_7;
899 supsmr |= UCC_UART_SUPSMR_CL_7;
900 char_length += 7;
901 break;
902 default: /* case CS8 */
903 upsmr |= UCC_UART_UPSMR_CL_8;
904 supsmr |= UCC_UART_SUPSMR_CL_8;
905 char_length += 8;
906 break;
907 }
908
909 /* If CSTOPB is set, we want two stop bits */
910 if (termios->c_cflag & CSTOPB) {
911 upsmr |= UCC_UART_UPSMR_SL;
912 supsmr |= UCC_UART_SUPSMR_SL;
913 char_length++; /* + SL */
914 }
915
916 if (termios->c_cflag & PARENB) {
917 upsmr |= UCC_UART_UPSMR_PEN;
918 supsmr |= UCC_UART_SUPSMR_PEN;
919 char_length++; /* + PEN */
920
921 if (!(termios->c_cflag & PARODD)) {
922 upsmr &= ~(UCC_UART_UPSMR_RPM_MASK |
923 UCC_UART_UPSMR_TPM_MASK);
924 upsmr |= UCC_UART_UPSMR_RPM_EVEN |
925 UCC_UART_UPSMR_TPM_EVEN;
926 supsmr &= ~(UCC_UART_SUPSMR_RPM_MASK |
927 UCC_UART_SUPSMR_TPM_MASK);
928 supsmr |= UCC_UART_SUPSMR_RPM_EVEN |
929 UCC_UART_SUPSMR_TPM_EVEN;
930 }
931 }
932
933 /*
934 * Set up parity check flag
935 */
936 port->read_status_mask = BD_SC_EMPTY | BD_SC_OV;
937 if (termios->c_iflag & INPCK)
938 port->read_status_mask |= BD_SC_FR | BD_SC_PR;
939 if (termios->c_iflag & (BRKINT | PARMRK))
940 port->read_status_mask |= BD_SC_BR;
941
942 /*
943 * Characters to ignore
944 */
945 port->ignore_status_mask = 0;
946 if (termios->c_iflag & IGNPAR)
947 port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
948 if (termios->c_iflag & IGNBRK) {
949 port->ignore_status_mask |= BD_SC_BR;
950 /*
951 * If we're ignore parity and break indicators, ignore
952 * overruns too. (For real raw support).
953 */
954 if (termios->c_iflag & IGNPAR)
955 port->ignore_status_mask |= BD_SC_OV;
956 }
957 /*
958 * !!! ignore all characters if CREAD is not set
959 */
960 if ((termios->c_cflag & CREAD) == 0)
961 port->read_status_mask &= ~BD_SC_EMPTY;
962
963 baud = uart_get_baud_rate(port, termios, old, 0, 115200);
964
965 /* Do we really need a spinlock here? */
966 spin_lock_irqsave(&port->lock, flags);
967
968 /* Update the per-port timeout. */
969 uart_update_timeout(port, termios->c_cflag, baud);
970
971 out_be16(&uccp->upsmr, upsmr);
972 if (soft_uart) {
973 out_be16(&uccup->supsmr, supsmr);
974 out_8(&uccup->rx_length, char_length);
975
976 /* Soft-UART requires a 1X multiplier for TX */
977 qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
978 qe_setbrg(qe_port->us_info.tx_clock, baud, 1);
979 } else {
980 qe_setbrg(qe_port->us_info.rx_clock, baud, 16);
981 qe_setbrg(qe_port->us_info.tx_clock, baud, 16);
982 }
983
984 spin_unlock_irqrestore(&port->lock, flags);
985}
986
987/*
988 * Return a pointer to a string that describes what kind of port this is.
989 */
990static const char *qe_uart_type(struct uart_port *port)
991{
992 return "QE";
993}
994
995/*
996 * Allocate any memory and I/O resources required by the port.
997 */
998static int qe_uart_request_port(struct uart_port *port)
999{
1000 int ret;
1001 struct uart_qe_port *qe_port =
1002 container_of(port, struct uart_qe_port, port);
1003 struct ucc_slow_info *us_info = &qe_port->us_info;
1004 struct ucc_slow_private *uccs;
1005 unsigned int rx_size, tx_size;
1006 void *bd_virt;
1007 dma_addr_t bd_dma_addr = 0;
1008
1009 ret = ucc_slow_init(us_info, &uccs);
1010 if (ret) {
1011 dev_err(port->dev, "could not initialize UCC%u\n",
1012 qe_port->ucc_num);
1013 return ret;
1014 }
1015
1016 qe_port->us_private = uccs;
1017 qe_port->uccp = uccs->us_regs;
1018 qe_port->uccup = (struct ucc_uart_pram *) uccs->us_pram;
1019 qe_port->rx_bd_base = uccs->rx_bd;
1020 qe_port->tx_bd_base = uccs->tx_bd;
1021
1022 /*
1023 * Allocate the transmit and receive data buffers.
1024 */
1025
1026 rx_size = L1_CACHE_ALIGN(qe_port->rx_nrfifos * qe_port->rx_fifosize);
1027 tx_size = L1_CACHE_ALIGN(qe_port->tx_nrfifos * qe_port->tx_fifosize);
1028
1029 bd_virt = dma_alloc_coherent(port->dev, rx_size + tx_size, &bd_dma_addr,
1030 GFP_KERNEL);
1031 if (!bd_virt) {
1032 dev_err(port->dev, "could not allocate buffer descriptors\n");
1033 return -ENOMEM;
1034 }
1035
1036 qe_port->bd_virt = bd_virt;
1037 qe_port->bd_dma_addr = bd_dma_addr;
1038 qe_port->bd_size = rx_size + tx_size;
1039
1040 qe_port->rx_buf = bd_virt;
1041 qe_port->tx_buf = qe_port->rx_buf + rx_size;
1042
1043 return 0;
1044}
1045
1046/*
1047 * Configure the port.
1048 *
1049 * We say we're a CPM-type port because that's mostly true. Once the device
1050 * is configured, this driver operates almost identically to the CPM serial
1051 * driver.
1052 */
1053static void qe_uart_config_port(struct uart_port *port, int flags)
1054{
1055 if (flags & UART_CONFIG_TYPE) {
1056 port->type = PORT_CPM;
1057 qe_uart_request_port(port);
1058 }
1059}
1060
1061/*
1062 * Release any memory and I/O resources that were allocated in
1063 * qe_uart_request_port().
1064 */
1065static void qe_uart_release_port(struct uart_port *port)
1066{
1067 struct uart_qe_port *qe_port =
1068 container_of(port, struct uart_qe_port, port);
1069 struct ucc_slow_private *uccs = qe_port->us_private;
1070
1071 dma_free_coherent(port->dev, qe_port->bd_size, qe_port->bd_virt,
1072 qe_port->bd_dma_addr);
1073
1074 ucc_slow_free(uccs);
1075}
1076
1077/*
1078 * Verify that the data in serial_struct is suitable for this device.
1079 */
1080static int qe_uart_verify_port(struct uart_port *port,
1081 struct serial_struct *ser)
1082{
1083 if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
1084 return -EINVAL;
1085
1086 if (ser->irq < 0 || ser->irq >= nr_irqs)
1087 return -EINVAL;
1088
1089 if (ser->baud_base < 9600)
1090 return -EINVAL;
1091
1092 return 0;
1093}
1094/* UART operations
1095 *
1096 * Details on these functions can be found in Documentation/serial/driver
1097 */
1098static struct uart_ops qe_uart_pops = {
1099 .tx_empty = qe_uart_tx_empty,
1100 .set_mctrl = qe_uart_set_mctrl,
1101 .get_mctrl = qe_uart_get_mctrl,
1102 .stop_tx = qe_uart_stop_tx,
1103 .start_tx = qe_uart_start_tx,
1104 .stop_rx = qe_uart_stop_rx,
1105 .enable_ms = qe_uart_enable_ms,
1106 .break_ctl = qe_uart_break_ctl,
1107 .startup = qe_uart_startup,
1108 .shutdown = qe_uart_shutdown,
1109 .set_termios = qe_uart_set_termios,
1110 .type = qe_uart_type,
1111 .release_port = qe_uart_release_port,
1112 .request_port = qe_uart_request_port,
1113 .config_port = qe_uart_config_port,
1114 .verify_port = qe_uart_verify_port,
1115};
1116
1117/*
1118 * Obtain the SOC model number and revision level
1119 *
1120 * This function parses the device tree to obtain the SOC model. It then
1121 * reads the SVR register to the revision.
1122 *
1123 * The device tree stores the SOC model two different ways.
1124 *
1125 * The new way is:
1126 *
1127 * cpu@0 {
1128 * compatible = "PowerPC,8323";
1129 * device_type = "cpu";
1130 * ...
1131 *
1132 *
1133 * The old way is:
1134 * PowerPC,8323@0 {
1135 * device_type = "cpu";
1136 * ...
1137 *
1138 * This code first checks the new way, and then the old way.
1139 */
1140static unsigned int soc_info(unsigned int *rev_h, unsigned int *rev_l)
1141{
1142 struct device_node *np;
1143 const char *soc_string;
1144 unsigned int svr;
1145 unsigned int soc;
1146
1147 /* Find the CPU node */
1148 np = of_find_node_by_type(NULL, "cpu");
1149 if (!np)
1150 return 0;
1151 /* Find the compatible property */
1152 soc_string = of_get_property(np, "compatible", NULL);
1153 if (!soc_string)
1154 /* No compatible property, so try the name. */
1155 soc_string = np->name;
1156
1157 /* Extract the SOC number from the "PowerPC," string */
1158 if ((sscanf(soc_string, "PowerPC,%u", &soc) != 1) || !soc)
1159 return 0;
1160
1161 /* Get the revision from the SVR */
1162 svr = mfspr(SPRN_SVR);
1163 *rev_h = (svr >> 4) & 0xf;
1164 *rev_l = svr & 0xf;
1165
1166 return soc;
1167}
1168
1169/*
1170 * requst_firmware_nowait() callback function
1171 *
1172 * This function is called by the kernel when a firmware is made available,
1173 * or if it times out waiting for the firmware.
1174 */
1175static void uart_firmware_cont(const struct firmware *fw, void *context)
1176{
1177 struct qe_firmware *firmware;
1178 struct device *dev = context;
1179 int ret;
1180
1181 if (!fw) {
1182 dev_err(dev, "firmware not found\n");
1183 return;
1184 }
1185
1186 firmware = (struct qe_firmware *) fw->data;
1187
1188 if (firmware->header.length != fw->size) {
1189 dev_err(dev, "invalid firmware\n");
1190 goto out;
1191 }
1192
1193 ret = qe_upload_firmware(firmware);
1194 if (ret) {
1195 dev_err(dev, "could not load firmware\n");
1196 goto out;
1197 }
1198
1199 firmware_loaded = 1;
1200 out:
1201 release_firmware(fw);
1202}
1203
1204static int ucc_uart_probe(struct platform_device *ofdev)
1205{
1206 struct device_node *np = ofdev->dev.of_node;
1207 const unsigned int *iprop; /* Integer OF properties */
1208 const char *sprop; /* String OF properties */
1209 struct uart_qe_port *qe_port = NULL;
1210 struct resource res;
1211 int ret;
1212
1213 /*
1214 * Determine if we need Soft-UART mode
1215 */
1216 if (of_find_property(np, "soft-uart", NULL)) {
1217 dev_dbg(&ofdev->dev, "using Soft-UART mode\n");
1218 soft_uart = 1;
1219 }
1220
1221 /*
1222 * If we are using Soft-UART, determine if we need to upload the
1223 * firmware, too.
1224 */
1225 if (soft_uart) {
1226 struct qe_firmware_info *qe_fw_info;
1227
1228 qe_fw_info = qe_get_firmware_info();
1229
1230 /* Check if the firmware has been uploaded. */
1231 if (qe_fw_info && strstr(qe_fw_info->id, "Soft-UART")) {
1232 firmware_loaded = 1;
1233 } else {
1234 char filename[32];
1235 unsigned int soc;
1236 unsigned int rev_h;
1237 unsigned int rev_l;
1238
1239 soc = soc_info(&rev_h, &rev_l);
1240 if (!soc) {
1241 dev_err(&ofdev->dev, "unknown CPU model\n");
1242 return -ENXIO;
1243 }
1244 sprintf(filename, "fsl_qe_ucode_uart_%u_%u%u.bin",
1245 soc, rev_h, rev_l);
1246
1247 dev_info(&ofdev->dev, "waiting for firmware %s\n",
1248 filename);
1249
1250 /*
1251 * We call request_firmware_nowait instead of
1252 * request_firmware so that the driver can load and
1253 * initialize the ports without holding up the rest of
1254 * the kernel. If hotplug support is enabled in the
1255 * kernel, then we use it.
1256 */
1257 ret = request_firmware_nowait(THIS_MODULE,
1258 FW_ACTION_HOTPLUG, filename, &ofdev->dev,
1259 GFP_KERNEL, &ofdev->dev, uart_firmware_cont);
1260 if (ret) {
1261 dev_err(&ofdev->dev,
1262 "could not load firmware %s\n",
1263 filename);
1264 return ret;
1265 }
1266 }
1267 }
1268
1269 qe_port = kzalloc(sizeof(struct uart_qe_port), GFP_KERNEL);
1270 if (!qe_port) {
1271 dev_err(&ofdev->dev, "can't allocate QE port structure\n");
1272 return -ENOMEM;
1273 }
1274
1275 /* Search for IRQ and mapbase */
1276 ret = of_address_to_resource(np, 0, &res);
1277 if (ret) {
1278 dev_err(&ofdev->dev, "missing 'reg' property in device tree\n");
1279 goto out_free;
1280 }
1281 if (!res.start) {
1282 dev_err(&ofdev->dev, "invalid 'reg' property in device tree\n");
1283 ret = -EINVAL;
1284 goto out_free;
1285 }
1286 qe_port->port.mapbase = res.start;
1287
1288 /* Get the UCC number (device ID) */
1289 /* UCCs are numbered 1-7 */
1290 iprop = of_get_property(np, "cell-index", NULL);
1291 if (!iprop) {
1292 iprop = of_get_property(np, "device-id", NULL);
1293 if (!iprop) {
1294 dev_err(&ofdev->dev, "UCC is unspecified in "
1295 "device tree\n");
1296 ret = -EINVAL;
1297 goto out_free;
1298 }
1299 }
1300
1301 if ((*iprop < 1) || (*iprop > UCC_MAX_NUM)) {
1302 dev_err(&ofdev->dev, "no support for UCC%u\n", *iprop);
1303 ret = -ENODEV;
1304 goto out_free;
1305 }
1306 qe_port->ucc_num = *iprop - 1;
1307
1308 /*
1309 * In the future, we should not require the BRG to be specified in the
1310 * device tree. If no clock-source is specified, then just pick a BRG
1311 * to use. This requires a new QE library function that manages BRG
1312 * assignments.
1313 */
1314
1315 sprop = of_get_property(np, "rx-clock-name", NULL);
1316 if (!sprop) {
1317 dev_err(&ofdev->dev, "missing rx-clock-name in device tree\n");
1318 ret = -ENODEV;
1319 goto out_free;
1320 }
1321
1322 qe_port->us_info.rx_clock = qe_clock_source(sprop);
1323 if ((qe_port->us_info.rx_clock < QE_BRG1) ||
1324 (qe_port->us_info.rx_clock > QE_BRG16)) {
1325 dev_err(&ofdev->dev, "rx-clock-name must be a BRG for UART\n");
1326 ret = -ENODEV;
1327 goto out_free;
1328 }
1329
1330#ifdef LOOPBACK
1331 /* In internal loopback mode, TX and RX must use the same clock */
1332 qe_port->us_info.tx_clock = qe_port->us_info.rx_clock;
1333#else
1334 sprop = of_get_property(np, "tx-clock-name", NULL);
1335 if (!sprop) {
1336 dev_err(&ofdev->dev, "missing tx-clock-name in device tree\n");
1337 ret = -ENODEV;
1338 goto out_free;
1339 }
1340 qe_port->us_info.tx_clock = qe_clock_source(sprop);
1341#endif
1342 if ((qe_port->us_info.tx_clock < QE_BRG1) ||
1343 (qe_port->us_info.tx_clock > QE_BRG16)) {
1344 dev_err(&ofdev->dev, "tx-clock-name must be a BRG for UART\n");
1345 ret = -ENODEV;
1346 goto out_free;
1347 }
1348
1349 /* Get the port number, numbered 0-3 */
1350 iprop = of_get_property(np, "port-number", NULL);
1351 if (!iprop) {
1352 dev_err(&ofdev->dev, "missing port-number in device tree\n");
1353 ret = -EINVAL;
1354 goto out_free;
1355 }
1356 qe_port->port.line = *iprop;
1357 if (qe_port->port.line >= UCC_MAX_UART) {
1358 dev_err(&ofdev->dev, "port-number must be 0-%u\n",
1359 UCC_MAX_UART - 1);
1360 ret = -EINVAL;
1361 goto out_free;
1362 }
1363
1364 qe_port->port.irq = irq_of_parse_and_map(np, 0);
1365 if (qe_port->port.irq == 0) {
1366 dev_err(&ofdev->dev, "could not map IRQ for UCC%u\n",
1367 qe_port->ucc_num + 1);
1368 ret = -EINVAL;
1369 goto out_free;
1370 }
1371
1372 /*
1373 * Newer device trees have an "fsl,qe" compatible property for the QE
1374 * node, but we still need to support older device trees.
1375 */
1376 np = of_find_compatible_node(NULL, NULL, "fsl,qe");
1377 if (!np) {
1378 np = of_find_node_by_type(NULL, "qe");
1379 if (!np) {
1380 dev_err(&ofdev->dev, "could not find 'qe' node\n");
1381 ret = -EINVAL;
1382 goto out_free;
1383 }
1384 }
1385
1386 iprop = of_get_property(np, "brg-frequency", NULL);
1387 if (!iprop) {
1388 dev_err(&ofdev->dev,
1389 "missing brg-frequency in device tree\n");
1390 ret = -EINVAL;
1391 goto out_np;
1392 }
1393
1394 if (*iprop)
1395 qe_port->port.uartclk = *iprop;
1396 else {
1397 /*
1398 * Older versions of U-Boot do not initialize the brg-frequency
1399 * property, so in this case we assume the BRG frequency is
1400 * half the QE bus frequency.
1401 */
1402 iprop = of_get_property(np, "bus-frequency", NULL);
1403 if (!iprop) {
1404 dev_err(&ofdev->dev,
1405 "missing QE bus-frequency in device tree\n");
1406 ret = -EINVAL;
1407 goto out_np;
1408 }
1409 if (*iprop)
1410 qe_port->port.uartclk = *iprop / 2;
1411 else {
1412 dev_err(&ofdev->dev,
1413 "invalid QE bus-frequency in device tree\n");
1414 ret = -EINVAL;
1415 goto out_np;
1416 }
1417 }
1418
1419 spin_lock_init(&qe_port->port.lock);
1420 qe_port->np = np;
1421 qe_port->port.dev = &ofdev->dev;
1422 qe_port->port.ops = &qe_uart_pops;
1423 qe_port->port.iotype = UPIO_MEM;
1424
1425 qe_port->tx_nrfifos = TX_NUM_FIFO;
1426 qe_port->tx_fifosize = TX_BUF_SIZE;
1427 qe_port->rx_nrfifos = RX_NUM_FIFO;
1428 qe_port->rx_fifosize = RX_BUF_SIZE;
1429
1430 qe_port->wait_closing = UCC_WAIT_CLOSING;
1431 qe_port->port.fifosize = 512;
1432 qe_port->port.flags = UPF_BOOT_AUTOCONF | UPF_IOREMAP;
1433
1434 qe_port->us_info.ucc_num = qe_port->ucc_num;
1435 qe_port->us_info.regs = (phys_addr_t) res.start;
1436 qe_port->us_info.irq = qe_port->port.irq;
1437
1438 qe_port->us_info.rx_bd_ring_len = qe_port->rx_nrfifos;
1439 qe_port->us_info.tx_bd_ring_len = qe_port->tx_nrfifos;
1440
1441 /* Make sure ucc_slow_init() initializes both TX and RX */
1442 qe_port->us_info.init_tx = 1;
1443 qe_port->us_info.init_rx = 1;
1444
1445 /* Add the port to the uart sub-system. This will cause
1446 * qe_uart_config_port() to be called, so the us_info structure must
1447 * be initialized.
1448 */
1449 ret = uart_add_one_port(&ucc_uart_driver, &qe_port->port);
1450 if (ret) {
1451 dev_err(&ofdev->dev, "could not add /dev/ttyQE%u\n",
1452 qe_port->port.line);
1453 goto out_np;
1454 }
1455
1456 platform_set_drvdata(ofdev, qe_port);
1457
1458 dev_info(&ofdev->dev, "UCC%u assigned to /dev/ttyQE%u\n",
1459 qe_port->ucc_num + 1, qe_port->port.line);
1460
1461 /* Display the mknod command for this device */
1462 dev_dbg(&ofdev->dev, "mknod command is 'mknod /dev/ttyQE%u c %u %u'\n",
1463 qe_port->port.line, SERIAL_QE_MAJOR,
1464 SERIAL_QE_MINOR + qe_port->port.line);
1465
1466 return 0;
1467out_np:
1468 of_node_put(np);
1469out_free:
1470 kfree(qe_port);
1471 return ret;
1472}
1473
1474static int ucc_uart_remove(struct platform_device *ofdev)
1475{
1476 struct uart_qe_port *qe_port = platform_get_drvdata(ofdev);
1477
1478 dev_info(&ofdev->dev, "removing /dev/ttyQE%u\n", qe_port->port.line);
1479
1480 uart_remove_one_port(&ucc_uart_driver, &qe_port->port);
1481
1482 kfree(qe_port);
1483
1484 return 0;
1485}
1486
1487static struct of_device_id ucc_uart_match[] = {
1488 {
1489 .type = "serial",
1490 .compatible = "ucc_uart",
1491 },
1492 {},
1493};
1494MODULE_DEVICE_TABLE(of, ucc_uart_match);
1495
1496static struct platform_driver ucc_uart_of_driver = {
1497 .driver = {
1498 .name = "ucc_uart",
1499 .owner = THIS_MODULE,
1500 .of_match_table = ucc_uart_match,
1501 },
1502 .probe = ucc_uart_probe,
1503 .remove = ucc_uart_remove,
1504};
1505
1506static int __init ucc_uart_init(void)
1507{
1508 int ret;
1509
1510 printk(KERN_INFO "Freescale QUICC Engine UART device driver\n");
1511#ifdef LOOPBACK
1512 printk(KERN_INFO "ucc-uart: Using loopback mode\n");
1513#endif
1514
1515 ret = uart_register_driver(&ucc_uart_driver);
1516 if (ret) {
1517 printk(KERN_ERR "ucc-uart: could not register UART driver\n");
1518 return ret;
1519 }
1520
1521 ret = platform_driver_register(&ucc_uart_of_driver);
1522 if (ret) {
1523 printk(KERN_ERR
1524 "ucc-uart: could not register platform driver\n");
1525 uart_unregister_driver(&ucc_uart_driver);
1526 }
1527
1528 return ret;
1529}
1530
1531static void __exit ucc_uart_exit(void)
1532{
1533 printk(KERN_INFO
1534 "Freescale QUICC Engine UART device driver unloading\n");
1535
1536 platform_driver_unregister(&ucc_uart_of_driver);
1537 uart_unregister_driver(&ucc_uart_driver);
1538}
1539
1540module_init(ucc_uart_init);
1541module_exit(ucc_uart_exit);
1542
1543MODULE_DESCRIPTION("Freescale QUICC Engine (QE) UART");
1544MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
1545MODULE_LICENSE("GPL v2");
1546MODULE_ALIAS_CHARDEV_MAJOR(SERIAL_QE_MAJOR);
1547