1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Driver for CPM (SCC/SMC) serial ports; core driver
4 *
5 * Based on arch/ppc/cpm2_io/uart.c by Dan Malek
6 * Based on ppc8xx.c by Thomas Gleixner
7 * Based on drivers/serial/amba.c by Russell King
8 *
9 * Maintainer: Kumar Gala (galak@kernel.crashing.org) (CPM2)
10 * Pantelis Antoniou (panto@intracom.gr) (CPM1)
11 *
12 * Copyright (C) 2004, 2007 Freescale Semiconductor, Inc.
13 * (C) 2004 Intracom, S.A.
14 * (C) 2005-2006 MontaVista Software, Inc.
15 * Vitaly Bordug <vbordug@ru.mvista.com>
16 */
17
18 #include <linux/module.h>
19 #include <linux/tty.h>
20 #include <linux/tty_flip.h>
21 #include <linux/ioport.h>
22 #include <linux/init.h>
23 #include <linux/serial.h>
24 #include <linux/console.h>
25 #include <linux/sysrq.h>
26 #include <linux/device.h>
27 #include <linux/memblock.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/of_address.h>
30 #include <linux/of_irq.h>
31 #include <linux/of_platform.h>
32 #include <linux/gpio/consumer.h>
33 #include <linux/clk.h>
34
35 #include <sysdev/fsl_soc.h>
36
37 #include <asm/io.h>
38 #include <asm/irq.h>
39 #include <asm/delay.h>
40 #include <asm/udbg.h>
41
42 #include <linux/serial_core.h>
43 #include <linux/kernel.h>
44
45 #include "cpm_uart.h"
46
47
48 /**************************************************************/
49
50 static int cpm_uart_tx_pump(struct uart_port *port);
51 static void cpm_uart_initbd(struct uart_cpm_port *pinfo);
52
53 /**************************************************************/
54
55 #define HW_BUF_SPD_THRESHOLD 2400
56
cpm_line_cr_cmd(struct uart_cpm_port * port,int cmd)57 static void cpm_line_cr_cmd(struct uart_cpm_port *port, int cmd)
58 {
59 cpm_command(port->command, cmd);
60 }
61
62 /*
63 * Check, if transmit buffers are processed
64 */
cpm_uart_tx_empty(struct uart_port * port)65 static unsigned int cpm_uart_tx_empty(struct uart_port *port)
66 {
67 struct uart_cpm_port *pinfo =
68 container_of(port, struct uart_cpm_port, port);
69 cbd_t __iomem *bdp = pinfo->tx_bd_base;
70 int ret = 0;
71
72 while (1) {
73 if (in_be16(&bdp->cbd_sc) & BD_SC_READY)
74 break;
75
76 if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP) {
77 ret = TIOCSER_TEMT;
78 break;
79 }
80 bdp++;
81 }
82
83 pr_debug("CPM uart[%d]:tx_empty: %d\n", port->line, ret);
84
85 return ret;
86 }
87
cpm_uart_set_mctrl(struct uart_port * port,unsigned int mctrl)88 static void cpm_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
89 {
90 struct uart_cpm_port *pinfo =
91 container_of(port, struct uart_cpm_port, port);
92
93 if (pinfo->gpios[GPIO_RTS])
94 gpiod_set_value(pinfo->gpios[GPIO_RTS], !(mctrl & TIOCM_RTS));
95
96 if (pinfo->gpios[GPIO_DTR])
97 gpiod_set_value(pinfo->gpios[GPIO_DTR], !(mctrl & TIOCM_DTR));
98 }
99
cpm_uart_get_mctrl(struct uart_port * port)100 static unsigned int cpm_uart_get_mctrl(struct uart_port *port)
101 {
102 struct uart_cpm_port *pinfo =
103 container_of(port, struct uart_cpm_port, port);
104 unsigned int mctrl = TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
105
106 if (pinfo->gpios[GPIO_CTS]) {
107 if (gpiod_get_value(pinfo->gpios[GPIO_CTS]))
108 mctrl &= ~TIOCM_CTS;
109 }
110
111 if (pinfo->gpios[GPIO_DSR]) {
112 if (gpiod_get_value(pinfo->gpios[GPIO_DSR]))
113 mctrl &= ~TIOCM_DSR;
114 }
115
116 if (pinfo->gpios[GPIO_DCD]) {
117 if (gpiod_get_value(pinfo->gpios[GPIO_DCD]))
118 mctrl &= ~TIOCM_CAR;
119 }
120
121 if (pinfo->gpios[GPIO_RI]) {
122 if (!gpiod_get_value(pinfo->gpios[GPIO_RI]))
123 mctrl |= TIOCM_RNG;
124 }
125
126 return mctrl;
127 }
128
129 /*
130 * Stop transmitter
131 */
cpm_uart_stop_tx(struct uart_port * port)132 static void cpm_uart_stop_tx(struct uart_port *port)
133 {
134 struct uart_cpm_port *pinfo =
135 container_of(port, struct uart_cpm_port, port);
136 smc_t __iomem *smcp = pinfo->smcp;
137 scc_t __iomem *sccp = pinfo->sccp;
138
139 pr_debug("CPM uart[%d]:stop tx\n", port->line);
140
141 if (IS_SMC(pinfo))
142 clrbits8(&smcp->smc_smcm, SMCM_TX);
143 else
144 clrbits16(&sccp->scc_sccm, UART_SCCM_TX);
145 }
146
147 /*
148 * Start transmitter
149 */
cpm_uart_start_tx(struct uart_port * port)150 static void cpm_uart_start_tx(struct uart_port *port)
151 {
152 struct uart_cpm_port *pinfo =
153 container_of(port, struct uart_cpm_port, port);
154 smc_t __iomem *smcp = pinfo->smcp;
155 scc_t __iomem *sccp = pinfo->sccp;
156
157 pr_debug("CPM uart[%d]:start tx\n", port->line);
158
159 if (IS_SMC(pinfo)) {
160 if (in_8(&smcp->smc_smcm) & SMCM_TX)
161 return;
162 } else {
163 if (in_be16(&sccp->scc_sccm) & UART_SCCM_TX)
164 return;
165 }
166
167 if (cpm_uart_tx_pump(port) != 0) {
168 if (IS_SMC(pinfo)) {
169 setbits8(&smcp->smc_smcm, SMCM_TX);
170 } else {
171 setbits16(&sccp->scc_sccm, UART_SCCM_TX);
172 }
173 }
174 }
175
176 /*
177 * Stop receiver
178 */
cpm_uart_stop_rx(struct uart_port * port)179 static void cpm_uart_stop_rx(struct uart_port *port)
180 {
181 struct uart_cpm_port *pinfo =
182 container_of(port, struct uart_cpm_port, port);
183 smc_t __iomem *smcp = pinfo->smcp;
184 scc_t __iomem *sccp = pinfo->sccp;
185
186 pr_debug("CPM uart[%d]:stop rx\n", port->line);
187
188 if (IS_SMC(pinfo))
189 clrbits8(&smcp->smc_smcm, SMCM_RX);
190 else
191 clrbits16(&sccp->scc_sccm, UART_SCCM_RX);
192 }
193
194 /*
195 * Generate a break.
196 */
cpm_uart_break_ctl(struct uart_port * port,int break_state)197 static void cpm_uart_break_ctl(struct uart_port *port, int break_state)
198 {
199 struct uart_cpm_port *pinfo =
200 container_of(port, struct uart_cpm_port, port);
201
202 pr_debug("CPM uart[%d]:break ctrl, break_state: %d\n", port->line,
203 break_state);
204
205 if (break_state)
206 cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
207 else
208 cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX);
209 }
210
211 /*
212 * Transmit characters, refill buffer descriptor, if possible
213 */
cpm_uart_int_tx(struct uart_port * port)214 static void cpm_uart_int_tx(struct uart_port *port)
215 {
216 pr_debug("CPM uart[%d]:TX INT\n", port->line);
217
218 cpm_uart_tx_pump(port);
219 }
220
221 #ifdef CONFIG_CONSOLE_POLL
222 static int serial_polled;
223 #endif
224
225 /*
226 * Receive characters
227 */
cpm_uart_int_rx(struct uart_port * port)228 static void cpm_uart_int_rx(struct uart_port *port)
229 {
230 int i;
231 unsigned char ch;
232 u8 *cp;
233 struct tty_port *tport = &port->state->port;
234 struct uart_cpm_port *pinfo =
235 container_of(port, struct uart_cpm_port, port);
236 cbd_t __iomem *bdp;
237 u16 status;
238 unsigned int flg;
239
240 pr_debug("CPM uart[%d]:RX INT\n", port->line);
241
242 /* Just loop through the closed BDs and copy the characters into
243 * the buffer.
244 */
245 bdp = pinfo->rx_cur;
246 for (;;) {
247 #ifdef CONFIG_CONSOLE_POLL
248 if (unlikely(serial_polled)) {
249 serial_polled = 0;
250 return;
251 }
252 #endif
253 /* get status */
254 status = in_be16(&bdp->cbd_sc);
255 /* If this one is empty, return happy */
256 if (status & BD_SC_EMPTY)
257 break;
258
259 /* get number of characters, and check spce in flip-buffer */
260 i = in_be16(&bdp->cbd_datlen);
261
262 /* If we have not enough room in tty flip buffer, then we try
263 * later, which will be the next rx-interrupt or a timeout
264 */
265 if (tty_buffer_request_room(tport, i) < i) {
266 printk(KERN_WARNING "No room in flip buffer\n");
267 return;
268 }
269
270 /* get pointer */
271 cp = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
272
273 /* loop through the buffer */
274 while (i-- > 0) {
275 ch = *cp++;
276 port->icount.rx++;
277 flg = TTY_NORMAL;
278
279 if (status &
280 (BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV))
281 goto handle_error;
282 if (uart_handle_sysrq_char(port, ch))
283 continue;
284 #ifdef CONFIG_CONSOLE_POLL
285 if (unlikely(serial_polled)) {
286 serial_polled = 0;
287 return;
288 }
289 #endif
290 error_return:
291 tty_insert_flip_char(tport, ch, flg);
292
293 } /* End while (i--) */
294
295 /* This BD is ready to be used again. Clear status. get next */
296 clrbits16(&bdp->cbd_sc, BD_SC_BR | BD_SC_FR | BD_SC_PR |
297 BD_SC_OV | BD_SC_ID);
298 setbits16(&bdp->cbd_sc, BD_SC_EMPTY);
299
300 if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
301 bdp = pinfo->rx_bd_base;
302 else
303 bdp++;
304
305 } /* End for (;;) */
306
307 /* Write back buffer pointer */
308 pinfo->rx_cur = bdp;
309
310 /* activate BH processing */
311 tty_flip_buffer_push(tport);
312
313 return;
314
315 /* Error processing */
316
317 handle_error:
318 /* Statistics */
319 if (status & BD_SC_BR)
320 port->icount.brk++;
321 if (status & BD_SC_PR)
322 port->icount.parity++;
323 if (status & BD_SC_FR)
324 port->icount.frame++;
325 if (status & BD_SC_OV)
326 port->icount.overrun++;
327
328 /* Mask out ignored conditions */
329 status &= port->read_status_mask;
330
331 /* Handle the remaining ones */
332 if (status & BD_SC_BR)
333 flg = TTY_BREAK;
334 else if (status & BD_SC_PR)
335 flg = TTY_PARITY;
336 else if (status & BD_SC_FR)
337 flg = TTY_FRAME;
338
339 /* overrun does not affect the current character ! */
340 if (status & BD_SC_OV) {
341 ch = 0;
342 flg = TTY_OVERRUN;
343 /* We skip this buffer */
344 /* CHECK: Is really nothing senseful there */
345 /* ASSUMPTION: it contains nothing valid */
346 i = 0;
347 }
348 port->sysrq = 0;
349 goto error_return;
350 }
351
352 /*
353 * Asynchron mode interrupt handler
354 */
cpm_uart_int(int irq,void * data)355 static irqreturn_t cpm_uart_int(int irq, void *data)
356 {
357 u8 events;
358 struct uart_port *port = data;
359 struct uart_cpm_port *pinfo = (struct uart_cpm_port *)port;
360 smc_t __iomem *smcp = pinfo->smcp;
361 scc_t __iomem *sccp = pinfo->sccp;
362
363 pr_debug("CPM uart[%d]:IRQ\n", port->line);
364
365 if (IS_SMC(pinfo)) {
366 events = in_8(&smcp->smc_smce);
367 out_8(&smcp->smc_smce, events);
368 if (events & SMCM_BRKE)
369 uart_handle_break(port);
370 if (events & SMCM_RX)
371 cpm_uart_int_rx(port);
372 if (events & SMCM_TX)
373 cpm_uart_int_tx(port);
374 } else {
375 events = in_be16(&sccp->scc_scce);
376 out_be16(&sccp->scc_scce, events);
377 if (events & UART_SCCM_BRKE)
378 uart_handle_break(port);
379 if (events & UART_SCCM_RX)
380 cpm_uart_int_rx(port);
381 if (events & UART_SCCM_TX)
382 cpm_uart_int_tx(port);
383 }
384 return (events) ? IRQ_HANDLED : IRQ_NONE;
385 }
386
cpm_uart_startup(struct uart_port * port)387 static int cpm_uart_startup(struct uart_port *port)
388 {
389 int retval;
390 struct uart_cpm_port *pinfo =
391 container_of(port, struct uart_cpm_port, port);
392
393 pr_debug("CPM uart[%d]:startup\n", port->line);
394
395 /* If the port is not the console, make sure rx is disabled. */
396 if (!(pinfo->flags & FLAG_CONSOLE)) {
397 /* Disable UART rx */
398 if (IS_SMC(pinfo)) {
399 clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN);
400 clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX);
401 } else {
402 clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR);
403 clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
404 }
405 cpm_uart_initbd(pinfo);
406 if (IS_SMC(pinfo)) {
407 out_be32(&pinfo->smcup->smc_rstate, 0);
408 out_be32(&pinfo->smcup->smc_tstate, 0);
409 out_be16(&pinfo->smcup->smc_rbptr,
410 in_be16(&pinfo->smcup->smc_rbase));
411 out_be16(&pinfo->smcup->smc_tbptr,
412 in_be16(&pinfo->smcup->smc_tbase));
413 } else {
414 cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
415 }
416 }
417 /* Install interrupt handler. */
418 retval = request_irq(port->irq, cpm_uart_int, 0, "cpm_uart", port);
419 if (retval)
420 return retval;
421
422 /* Startup rx-int */
423 if (IS_SMC(pinfo)) {
424 setbits8(&pinfo->smcp->smc_smcm, SMCM_RX);
425 setbits16(&pinfo->smcp->smc_smcmr, (SMCMR_REN | SMCMR_TEN));
426 } else {
427 setbits16(&pinfo->sccp->scc_sccm, UART_SCCM_RX);
428 setbits32(&pinfo->sccp->scc_gsmrl, (SCC_GSMRL_ENR | SCC_GSMRL_ENT));
429 }
430
431 return 0;
432 }
433
cpm_uart_wait_until_send(struct uart_cpm_port * pinfo)434 inline void cpm_uart_wait_until_send(struct uart_cpm_port *pinfo)
435 {
436 set_current_state(TASK_UNINTERRUPTIBLE);
437 schedule_timeout(pinfo->wait_closing);
438 }
439
440 /*
441 * Shutdown the uart
442 */
cpm_uart_shutdown(struct uart_port * port)443 static void cpm_uart_shutdown(struct uart_port *port)
444 {
445 struct uart_cpm_port *pinfo =
446 container_of(port, struct uart_cpm_port, port);
447
448 pr_debug("CPM uart[%d]:shutdown\n", port->line);
449
450 /* free interrupt handler */
451 free_irq(port->irq, port);
452
453 /* If the port is not the console, disable Rx and Tx. */
454 if (!(pinfo->flags & FLAG_CONSOLE)) {
455 /* Wait for all the BDs marked sent */
456 while(!cpm_uart_tx_empty(port)) {
457 set_current_state(TASK_UNINTERRUPTIBLE);
458 schedule_timeout(2);
459 }
460
461 if (pinfo->wait_closing)
462 cpm_uart_wait_until_send(pinfo);
463
464 /* Stop uarts */
465 if (IS_SMC(pinfo)) {
466 smc_t __iomem *smcp = pinfo->smcp;
467 clrbits16(&smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
468 clrbits8(&smcp->smc_smcm, SMCM_RX | SMCM_TX);
469 } else {
470 scc_t __iomem *sccp = pinfo->sccp;
471 clrbits32(&sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
472 clrbits16(&sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
473 }
474
475 /* Shut them really down and reinit buffer descriptors */
476 if (IS_SMC(pinfo)) {
477 out_be16(&pinfo->smcup->smc_brkcr, 0);
478 cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
479 } else {
480 out_be16(&pinfo->sccup->scc_brkcr, 0);
481 cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX);
482 }
483
484 cpm_uart_initbd(pinfo);
485 }
486 }
487
cpm_uart_set_termios(struct uart_port * port,struct ktermios * termios,const struct ktermios * old)488 static void cpm_uart_set_termios(struct uart_port *port,
489 struct ktermios *termios,
490 const struct ktermios *old)
491 {
492 int baud;
493 unsigned long flags;
494 u16 cval, scval, prev_mode;
495 struct uart_cpm_port *pinfo =
496 container_of(port, struct uart_cpm_port, port);
497 smc_t __iomem *smcp = pinfo->smcp;
498 scc_t __iomem *sccp = pinfo->sccp;
499 int maxidl;
500
501 pr_debug("CPM uart[%d]:set_termios\n", port->line);
502
503 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
504 if (baud < HW_BUF_SPD_THRESHOLD || port->flags & UPF_LOW_LATENCY)
505 pinfo->rx_fifosize = 1;
506 else
507 pinfo->rx_fifosize = RX_BUF_SIZE;
508
509 /* MAXIDL is the timeout after which a receive buffer is closed
510 * when not full if no more characters are received.
511 * We calculate it from the baudrate so that the duration is
512 * always the same at standard rates: about 4ms.
513 */
514 maxidl = baud / 2400;
515 if (maxidl < 1)
516 maxidl = 1;
517 if (maxidl > 0x10)
518 maxidl = 0x10;
519
520 cval = 0;
521 scval = 0;
522
523 if (termios->c_cflag & CSTOPB) {
524 cval |= SMCMR_SL; /* Two stops */
525 scval |= SCU_PSMR_SL;
526 }
527
528 if (termios->c_cflag & PARENB) {
529 cval |= SMCMR_PEN;
530 scval |= SCU_PSMR_PEN;
531 if (!(termios->c_cflag & PARODD)) {
532 cval |= SMCMR_PM_EVEN;
533 scval |= (SCU_PSMR_REVP | SCU_PSMR_TEVP);
534 }
535 }
536
537 /*
538 * Update the timeout
539 */
540 uart_update_timeout(port, termios->c_cflag, baud);
541
542 /*
543 * Set up parity check flag
544 */
545 port->read_status_mask = (BD_SC_EMPTY | BD_SC_OV);
546 if (termios->c_iflag & INPCK)
547 port->read_status_mask |= BD_SC_FR | BD_SC_PR;
548 if ((termios->c_iflag & BRKINT) || (termios->c_iflag & PARMRK))
549 port->read_status_mask |= BD_SC_BR;
550
551 /*
552 * Characters to ignore
553 */
554 port->ignore_status_mask = 0;
555 if (termios->c_iflag & IGNPAR)
556 port->ignore_status_mask |= BD_SC_PR | BD_SC_FR;
557 if (termios->c_iflag & IGNBRK) {
558 port->ignore_status_mask |= BD_SC_BR;
559 /*
560 * If we're ignore parity and break indicators, ignore
561 * overruns too. (For real raw support).
562 */
563 if (termios->c_iflag & IGNPAR)
564 port->ignore_status_mask |= BD_SC_OV;
565 }
566 /*
567 * !!! ignore all characters if CREAD is not set
568 */
569 if ((termios->c_cflag & CREAD) == 0)
570 port->read_status_mask &= ~BD_SC_EMPTY;
571
572 uart_port_lock_irqsave(port, &flags);
573
574 if (IS_SMC(pinfo)) {
575 unsigned int bits = tty_get_frame_size(termios->c_cflag);
576
577 /*
578 * MRBLR can be changed while an SMC/SCC is operating only
579 * if it is done in a single bus cycle with one 16-bit move
580 * (not two 8-bit bus cycles back-to-back). This occurs when
581 * the cp shifts control to the next RxBD, so the change does
582 * not take effect immediately. To guarantee the exact RxBD
583 * on which the change occurs, change MRBLR only while the
584 * SMC/SCC receiver is disabled.
585 */
586 out_be16(&pinfo->smcup->smc_mrblr, pinfo->rx_fifosize);
587 out_be16(&pinfo->smcup->smc_maxidl, maxidl);
588
589 /* Set the mode register. We want to keep a copy of the
590 * enables, because we want to put them back if they were
591 * present.
592 */
593 prev_mode = in_be16(&smcp->smc_smcmr) & (SMCMR_REN | SMCMR_TEN);
594 /* Output in *one* operation, so we don't interrupt RX/TX if they
595 * were already enabled.
596 * Character length programmed into the register is frame bits minus 1.
597 */
598 out_be16(&smcp->smc_smcmr, smcr_mk_clen(bits - 1) | cval |
599 SMCMR_SM_UART | prev_mode);
600 } else {
601 unsigned int bits = tty_get_char_size(termios->c_cflag);
602
603 out_be16(&pinfo->sccup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
604 out_be16(&pinfo->sccup->scc_maxidl, maxidl);
605 out_be16(&sccp->scc_psmr, (UART_LCR_WLEN(bits) << 12) | scval);
606 }
607
608 if (pinfo->clk)
609 clk_set_rate(pinfo->clk, baud);
610 else
611 cpm_setbrg(pinfo->brg - 1, baud);
612 uart_port_unlock_irqrestore(port, flags);
613 }
614
cpm_uart_type(struct uart_port * port)615 static const char *cpm_uart_type(struct uart_port *port)
616 {
617 pr_debug("CPM uart[%d]:uart_type\n", port->line);
618
619 return port->type == PORT_CPM ? "CPM UART" : NULL;
620 }
621
622 /*
623 * verify the new serial_struct (for TIOCSSERIAL).
624 */
cpm_uart_verify_port(struct uart_port * port,struct serial_struct * ser)625 static int cpm_uart_verify_port(struct uart_port *port,
626 struct serial_struct *ser)
627 {
628 int ret = 0;
629
630 pr_debug("CPM uart[%d]:verify_port\n", port->line);
631
632 if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
633 ret = -EINVAL;
634 if (ser->irq < 0 || ser->irq >= irq_get_nr_irqs())
635 ret = -EINVAL;
636 if (ser->baud_base < 9600)
637 ret = -EINVAL;
638 return ret;
639 }
640
641 /*
642 * Transmit characters, refill buffer descriptor, if possible
643 */
cpm_uart_tx_pump(struct uart_port * port)644 static int cpm_uart_tx_pump(struct uart_port *port)
645 {
646 cbd_t __iomem *bdp;
647 u8 *p;
648 int count;
649 struct uart_cpm_port *pinfo =
650 container_of(port, struct uart_cpm_port, port);
651 struct tty_port *tport = &port->state->port;
652
653 /* Handle xon/xoff */
654 if (port->x_char) {
655 /* Pick next descriptor and fill from buffer */
656 bdp = pinfo->tx_cur;
657
658 p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
659
660 *p++ = port->x_char;
661
662 out_be16(&bdp->cbd_datlen, 1);
663 setbits16(&bdp->cbd_sc, BD_SC_READY);
664 /* Get next BD. */
665 if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
666 bdp = pinfo->tx_bd_base;
667 else
668 bdp++;
669 pinfo->tx_cur = bdp;
670
671 port->icount.tx++;
672 port->x_char = 0;
673 return 1;
674 }
675
676 if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) {
677 cpm_uart_stop_tx(port);
678 return 0;
679 }
680
681 /* Pick next descriptor and fill from buffer */
682 bdp = pinfo->tx_cur;
683
684 while (!(in_be16(&bdp->cbd_sc) & BD_SC_READY) &&
685 !kfifo_is_empty(&tport->xmit_fifo)) {
686 p = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr), pinfo);
687 count = uart_fifo_out(port, p, pinfo->tx_fifosize);
688 out_be16(&bdp->cbd_datlen, count);
689 setbits16(&bdp->cbd_sc, BD_SC_READY);
690 /* Get next BD. */
691 if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
692 bdp = pinfo->tx_bd_base;
693 else
694 bdp++;
695 }
696 pinfo->tx_cur = bdp;
697
698 if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
699 uart_write_wakeup(port);
700
701 if (kfifo_is_empty(&tport->xmit_fifo)) {
702 cpm_uart_stop_tx(port);
703 return 0;
704 }
705
706 return 1;
707 }
708
709 /*
710 * init buffer descriptors
711 */
cpm_uart_initbd(struct uart_cpm_port * pinfo)712 static void cpm_uart_initbd(struct uart_cpm_port *pinfo)
713 {
714 int i;
715 u8 *mem_addr;
716 cbd_t __iomem *bdp;
717
718 pr_debug("CPM uart[%d]:initbd\n", pinfo->port.line);
719
720 /* Set the physical address of the host memory
721 * buffers in the buffer descriptors, and the
722 * virtual address for us to work with.
723 */
724 mem_addr = pinfo->mem_addr;
725 bdp = pinfo->rx_cur = pinfo->rx_bd_base;
726 for (i = 0; i < (pinfo->rx_nrfifos - 1); i++, bdp++) {
727 out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
728 out_be16(&bdp->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT);
729 mem_addr += pinfo->rx_fifosize;
730 }
731
732 out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
733 out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_EMPTY | BD_SC_INTRPT);
734
735 /* Set the physical address of the host memory
736 * buffers in the buffer descriptors, and the
737 * virtual address for us to work with.
738 */
739 mem_addr = pinfo->mem_addr + L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize);
740 bdp = pinfo->tx_cur = pinfo->tx_bd_base;
741 for (i = 0; i < (pinfo->tx_nrfifos - 1); i++, bdp++) {
742 out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
743 out_be16(&bdp->cbd_sc, BD_SC_INTRPT);
744 mem_addr += pinfo->tx_fifosize;
745 }
746
747 out_be32(&bdp->cbd_bufaddr, cpu2cpm_addr(mem_addr, pinfo));
748 out_be16(&bdp->cbd_sc, BD_SC_WRAP | BD_SC_INTRPT);
749 }
750
cpm_uart_init_scc(struct uart_cpm_port * pinfo)751 static void cpm_uart_init_scc(struct uart_cpm_port *pinfo)
752 {
753 scc_t __iomem *scp;
754 scc_uart_t __iomem *sup;
755
756 pr_debug("CPM uart[%d]:init_scc\n", pinfo->port.line);
757
758 scp = pinfo->sccp;
759 sup = pinfo->sccup;
760
761 /* Store address */
762 out_be16(&pinfo->sccup->scc_genscc.scc_rbase,
763 (u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE);
764 out_be16(&pinfo->sccup->scc_genscc.scc_tbase,
765 (u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE);
766
767 /* Set up the uart parameters in the
768 * parameter ram.
769 */
770
771 out_8(&sup->scc_genscc.scc_rfcr, CPMFCR_GBL | CPMFCR_EB);
772 out_8(&sup->scc_genscc.scc_tfcr, CPMFCR_GBL | CPMFCR_EB);
773
774 out_be16(&sup->scc_genscc.scc_mrblr, pinfo->rx_fifosize);
775 out_be16(&sup->scc_maxidl, 0x10);
776 out_be16(&sup->scc_brkcr, 1);
777 out_be16(&sup->scc_parec, 0);
778 out_be16(&sup->scc_frmec, 0);
779 out_be16(&sup->scc_nosec, 0);
780 out_be16(&sup->scc_brkec, 0);
781 out_be16(&sup->scc_uaddr1, 0);
782 out_be16(&sup->scc_uaddr2, 0);
783 out_be16(&sup->scc_toseq, 0);
784 out_be16(&sup->scc_char1, 0x8000);
785 out_be16(&sup->scc_char2, 0x8000);
786 out_be16(&sup->scc_char3, 0x8000);
787 out_be16(&sup->scc_char4, 0x8000);
788 out_be16(&sup->scc_char5, 0x8000);
789 out_be16(&sup->scc_char6, 0x8000);
790 out_be16(&sup->scc_char7, 0x8000);
791 out_be16(&sup->scc_char8, 0x8000);
792 out_be16(&sup->scc_rccm, 0xc0ff);
793
794 /* Send the CPM an initialize command.
795 */
796 cpm_line_cr_cmd(pinfo, CPM_CR_INIT_TRX);
797
798 /* Set UART mode, 8 bit, no parity, one stop.
799 * Enable receive and transmit.
800 */
801 out_be32(&scp->scc_gsmrh, 0);
802 out_be32(&scp->scc_gsmrl,
803 SCC_GSMRL_MODE_UART | SCC_GSMRL_TDCR_16 | SCC_GSMRL_RDCR_16);
804
805 /* Enable rx interrupts and clear all pending events. */
806 out_be16(&scp->scc_sccm, 0);
807 out_be16(&scp->scc_scce, 0xffff);
808 out_be16(&scp->scc_dsr, 0x7e7e);
809 out_be16(&scp->scc_psmr, 0x3000);
810
811 setbits32(&scp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
812 }
813
cpm_uart_init_smc(struct uart_cpm_port * pinfo)814 static void cpm_uart_init_smc(struct uart_cpm_port *pinfo)
815 {
816 smc_t __iomem *sp;
817 smc_uart_t __iomem *up;
818
819 pr_debug("CPM uart[%d]:init_smc\n", pinfo->port.line);
820
821 sp = pinfo->smcp;
822 up = pinfo->smcup;
823
824 /* Store address */
825 out_be16(&pinfo->smcup->smc_rbase,
826 (u8 __iomem *)pinfo->rx_bd_base - DPRAM_BASE);
827 out_be16(&pinfo->smcup->smc_tbase,
828 (u8 __iomem *)pinfo->tx_bd_base - DPRAM_BASE);
829
830 /*
831 * In case SMC is being relocated...
832 */
833 out_be16(&up->smc_rbptr, in_be16(&pinfo->smcup->smc_rbase));
834 out_be16(&up->smc_tbptr, in_be16(&pinfo->smcup->smc_tbase));
835 out_be32(&up->smc_rstate, 0);
836 out_be32(&up->smc_tstate, 0);
837 out_be16(&up->smc_brkcr, 1); /* number of break chars */
838 out_be16(&up->smc_brkec, 0);
839
840 /* Set up the uart parameters in the
841 * parameter ram.
842 */
843 out_8(&up->smc_rfcr, CPMFCR_GBL | CPMFCR_EB);
844 out_8(&up->smc_tfcr, CPMFCR_GBL | CPMFCR_EB);
845
846 /* Using idle character time requires some additional tuning. */
847 out_be16(&up->smc_mrblr, pinfo->rx_fifosize);
848 out_be16(&up->smc_maxidl, 0x10);
849 out_be16(&up->smc_brklen, 0);
850 out_be16(&up->smc_brkec, 0);
851 out_be16(&up->smc_brkcr, 1);
852
853 /* Set UART mode, 8 bit, no parity, one stop.
854 * Enable receive and transmit.
855 */
856 out_be16(&sp->smc_smcmr, smcr_mk_clen(9) | SMCMR_SM_UART);
857
858 /* Enable only rx interrupts clear all pending events. */
859 out_8(&sp->smc_smcm, 0);
860 out_8(&sp->smc_smce, 0xff);
861
862 setbits16(&sp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
863 }
864
865 /*
866 * Allocate DP-Ram and memory buffers. We need to allocate a transmit and
867 * receive buffer descriptors from dual port ram, and a character
868 * buffer area from host mem. If we are allocating for the console we need
869 * to do it from bootmem
870 */
cpm_uart_allocbuf(struct uart_cpm_port * pinfo,unsigned int is_con)871 static int cpm_uart_allocbuf(struct uart_cpm_port *pinfo, unsigned int is_con)
872 {
873 int dpmemsz, memsz;
874 u8 __iomem *dp_mem;
875 unsigned long dp_offset;
876 u8 *mem_addr;
877 dma_addr_t dma_addr = 0;
878
879 pr_debug("CPM uart[%d]:allocbuf\n", pinfo->port.line);
880
881 dpmemsz = sizeof(cbd_t) * (pinfo->rx_nrfifos + pinfo->tx_nrfifos);
882 dp_offset = cpm_muram_alloc(dpmemsz, 8);
883 if (IS_ERR_VALUE(dp_offset)) {
884 pr_err("%s: could not allocate buffer descriptors\n", __func__);
885 return -ENOMEM;
886 }
887
888 dp_mem = cpm_muram_addr(dp_offset);
889
890 memsz = L1_CACHE_ALIGN(pinfo->rx_nrfifos * pinfo->rx_fifosize) +
891 L1_CACHE_ALIGN(pinfo->tx_nrfifos * pinfo->tx_fifosize);
892 if (IS_ENABLED(CONFIG_CPM1) && is_con) {
893 /* was hostalloc but changed cause it blows away the */
894 /* large tlb mapping when pinning the kernel area */
895 mem_addr = (u8 __force *)cpm_muram_addr(cpm_muram_alloc(memsz, 8));
896 dma_addr = cpm_muram_dma((void __iomem *)mem_addr);
897 } else if (is_con) {
898 mem_addr = kzalloc(memsz, GFP_NOWAIT);
899 dma_addr = virt_to_bus(mem_addr);
900 } else {
901 mem_addr = dma_alloc_coherent(pinfo->port.dev, memsz, &dma_addr,
902 GFP_KERNEL);
903 }
904
905 if (!mem_addr) {
906 cpm_muram_free(dp_offset);
907 pr_err("%s: could not allocate coherent memory\n", __func__);
908 return -ENOMEM;
909 }
910
911 pinfo->dp_addr = dp_offset;
912 pinfo->mem_addr = mem_addr;
913 pinfo->dma_addr = dma_addr;
914 pinfo->mem_size = memsz;
915
916 pinfo->rx_buf = mem_addr;
917 pinfo->tx_buf = pinfo->rx_buf + L1_CACHE_ALIGN(pinfo->rx_nrfifos
918 * pinfo->rx_fifosize);
919
920 pinfo->rx_bd_base = (cbd_t __iomem *)dp_mem;
921 pinfo->tx_bd_base = pinfo->rx_bd_base + pinfo->rx_nrfifos;
922
923 return 0;
924 }
925
cpm_uart_freebuf(struct uart_cpm_port * pinfo)926 static void cpm_uart_freebuf(struct uart_cpm_port *pinfo)
927 {
928 dma_free_coherent(pinfo->port.dev, L1_CACHE_ALIGN(pinfo->rx_nrfifos *
929 pinfo->rx_fifosize) +
930 L1_CACHE_ALIGN(pinfo->tx_nrfifos *
931 pinfo->tx_fifosize), (void __force *)pinfo->mem_addr,
932 pinfo->dma_addr);
933
934 cpm_muram_free(pinfo->dp_addr);
935 }
936
937 /*
938 * Initialize port. This is called from early_console stuff
939 * so we have to be careful here !
940 */
cpm_uart_request_port(struct uart_port * port)941 static int cpm_uart_request_port(struct uart_port *port)
942 {
943 struct uart_cpm_port *pinfo =
944 container_of(port, struct uart_cpm_port, port);
945 int ret;
946
947 pr_debug("CPM uart[%d]:request port\n", port->line);
948
949 if (pinfo->flags & FLAG_CONSOLE)
950 return 0;
951
952 if (IS_SMC(pinfo)) {
953 clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX);
954 clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
955 } else {
956 clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
957 clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
958 }
959
960 ret = cpm_uart_allocbuf(pinfo, 0);
961
962 if (ret)
963 return ret;
964
965 cpm_uart_initbd(pinfo);
966 if (IS_SMC(pinfo))
967 cpm_uart_init_smc(pinfo);
968 else
969 cpm_uart_init_scc(pinfo);
970
971 return 0;
972 }
973
cpm_uart_release_port(struct uart_port * port)974 static void cpm_uart_release_port(struct uart_port *port)
975 {
976 struct uart_cpm_port *pinfo =
977 container_of(port, struct uart_cpm_port, port);
978
979 if (!(pinfo->flags & FLAG_CONSOLE))
980 cpm_uart_freebuf(pinfo);
981 }
982
983 /*
984 * Configure/autoconfigure the port.
985 */
cpm_uart_config_port(struct uart_port * port,int flags)986 static void cpm_uart_config_port(struct uart_port *port, int flags)
987 {
988 pr_debug("CPM uart[%d]:config_port\n", port->line);
989
990 if (flags & UART_CONFIG_TYPE) {
991 port->type = PORT_CPM;
992 cpm_uart_request_port(port);
993 }
994 }
995
996 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_CPM_CONSOLE)
997 /*
998 * Write a string to the serial port
999 * Note that this is called with interrupts already disabled
1000 */
cpm_uart_early_write(struct uart_cpm_port * pinfo,const char * string,u_int count,bool handle_linefeed)1001 static void cpm_uart_early_write(struct uart_cpm_port *pinfo,
1002 const char *string, u_int count, bool handle_linefeed)
1003 {
1004 unsigned int i;
1005 cbd_t __iomem *bdp, *bdbase;
1006 unsigned char *cpm_outp_addr;
1007
1008 /* Get the address of the host memory buffer.
1009 */
1010 bdp = pinfo->tx_cur;
1011 bdbase = pinfo->tx_bd_base;
1012
1013 /*
1014 * Now, do each character. This is not as bad as it looks
1015 * since this is a holding FIFO and not a transmitting FIFO.
1016 * We could add the complexity of filling the entire transmit
1017 * buffer, but we would just wait longer between accesses......
1018 */
1019 for (i = 0; i < count; i++, string++) {
1020 /* Wait for transmitter fifo to empty.
1021 * Ready indicates output is ready, and xmt is doing
1022 * that, not that it is ready for us to send.
1023 */
1024 while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
1025 ;
1026
1027 /* Send the character out.
1028 * If the buffer address is in the CPM DPRAM, don't
1029 * convert it.
1030 */
1031 cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr),
1032 pinfo);
1033 *cpm_outp_addr = *string;
1034
1035 out_be16(&bdp->cbd_datlen, 1);
1036 setbits16(&bdp->cbd_sc, BD_SC_READY);
1037
1038 if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
1039 bdp = bdbase;
1040 else
1041 bdp++;
1042
1043 /* if a LF, also do CR... */
1044 if (handle_linefeed && *string == 10) {
1045 while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
1046 ;
1047
1048 cpm_outp_addr = cpm2cpu_addr(in_be32(&bdp->cbd_bufaddr),
1049 pinfo);
1050 *cpm_outp_addr = 13;
1051
1052 out_be16(&bdp->cbd_datlen, 1);
1053 setbits16(&bdp->cbd_sc, BD_SC_READY);
1054
1055 if (in_be16(&bdp->cbd_sc) & BD_SC_WRAP)
1056 bdp = bdbase;
1057 else
1058 bdp++;
1059 }
1060 }
1061
1062 /*
1063 * Finally, Wait for transmitter & holding register to empty
1064 * and restore the IER
1065 */
1066 while ((in_be16(&bdp->cbd_sc) & BD_SC_READY) != 0)
1067 ;
1068
1069 pinfo->tx_cur = bdp;
1070 }
1071 #endif
1072
1073 #ifdef CONFIG_CONSOLE_POLL
1074 /* Serial polling routines for writing and reading from the uart while
1075 * in an interrupt or debug context.
1076 */
1077
1078 #define GDB_BUF_SIZE 512 /* power of 2, please */
1079
1080 static char poll_buf[GDB_BUF_SIZE];
1081 static char *pollp;
1082 static int poll_chars;
1083
poll_wait_key(char * obuf,struct uart_cpm_port * pinfo)1084 static int poll_wait_key(char *obuf, struct uart_cpm_port *pinfo)
1085 {
1086 u_char c, *cp;
1087 volatile cbd_t *bdp;
1088 int i;
1089
1090 /* Get the address of the host memory buffer.
1091 */
1092 bdp = pinfo->rx_cur;
1093 if (bdp->cbd_sc & BD_SC_EMPTY)
1094 return NO_POLL_CHAR;
1095
1096 /* If the buffer address is in the CPM DPRAM, don't
1097 * convert it.
1098 */
1099 cp = cpm2cpu_addr(bdp->cbd_bufaddr, pinfo);
1100
1101 if (obuf) {
1102 i = c = bdp->cbd_datlen;
1103 while (i-- > 0)
1104 *obuf++ = *cp++;
1105 } else
1106 c = *cp;
1107 bdp->cbd_sc &= ~(BD_SC_BR | BD_SC_FR | BD_SC_PR | BD_SC_OV | BD_SC_ID);
1108 bdp->cbd_sc |= BD_SC_EMPTY;
1109
1110 if (bdp->cbd_sc & BD_SC_WRAP)
1111 bdp = pinfo->rx_bd_base;
1112 else
1113 bdp++;
1114 pinfo->rx_cur = (cbd_t *)bdp;
1115
1116 return (int)c;
1117 }
1118
cpm_get_poll_char(struct uart_port * port)1119 static int cpm_get_poll_char(struct uart_port *port)
1120 {
1121 struct uart_cpm_port *pinfo =
1122 container_of(port, struct uart_cpm_port, port);
1123
1124 if (!serial_polled) {
1125 serial_polled = 1;
1126 poll_chars = 0;
1127 }
1128 if (poll_chars <= 0) {
1129 int ret = poll_wait_key(poll_buf, pinfo);
1130
1131 if (ret == NO_POLL_CHAR)
1132 return ret;
1133 poll_chars = ret;
1134 pollp = poll_buf;
1135 }
1136 poll_chars--;
1137 return *pollp++;
1138 }
1139
cpm_put_poll_char(struct uart_port * port,unsigned char c)1140 static void cpm_put_poll_char(struct uart_port *port,
1141 unsigned char c)
1142 {
1143 struct uart_cpm_port *pinfo =
1144 container_of(port, struct uart_cpm_port, port);
1145 static char ch[2];
1146
1147 ch[0] = (char)c;
1148 cpm_uart_early_write(pinfo, ch, 1, false);
1149 }
1150
1151 #ifdef CONFIG_SERIAL_CPM_CONSOLE
1152 static struct uart_port *udbg_port;
1153
udbg_cpm_putc(char c)1154 static void udbg_cpm_putc(char c)
1155 {
1156 if (c == '\n')
1157 cpm_put_poll_char(udbg_port, '\r');
1158 cpm_put_poll_char(udbg_port, c);
1159 }
1160
udbg_cpm_getc_poll(void)1161 static int udbg_cpm_getc_poll(void)
1162 {
1163 int c = cpm_get_poll_char(udbg_port);
1164
1165 return c == NO_POLL_CHAR ? -1 : c;
1166 }
1167
udbg_cpm_getc(void)1168 static int udbg_cpm_getc(void)
1169 {
1170 int c;
1171
1172 while ((c = udbg_cpm_getc_poll()) == -1)
1173 cpu_relax();
1174 return c;
1175 }
1176 #endif /* CONFIG_SERIAL_CPM_CONSOLE */
1177
1178 #endif /* CONFIG_CONSOLE_POLL */
1179
1180 static const struct uart_ops cpm_uart_pops = {
1181 .tx_empty = cpm_uart_tx_empty,
1182 .set_mctrl = cpm_uart_set_mctrl,
1183 .get_mctrl = cpm_uart_get_mctrl,
1184 .stop_tx = cpm_uart_stop_tx,
1185 .start_tx = cpm_uart_start_tx,
1186 .stop_rx = cpm_uart_stop_rx,
1187 .break_ctl = cpm_uart_break_ctl,
1188 .startup = cpm_uart_startup,
1189 .shutdown = cpm_uart_shutdown,
1190 .set_termios = cpm_uart_set_termios,
1191 .type = cpm_uart_type,
1192 .release_port = cpm_uart_release_port,
1193 .request_port = cpm_uart_request_port,
1194 .config_port = cpm_uart_config_port,
1195 .verify_port = cpm_uart_verify_port,
1196 #ifdef CONFIG_CONSOLE_POLL
1197 .poll_get_char = cpm_get_poll_char,
1198 .poll_put_char = cpm_put_poll_char,
1199 #endif
1200 };
1201
1202 static struct uart_cpm_port cpm_uart_ports[UART_NR];
1203
cpm_uart_map_pram(struct uart_cpm_port * port,struct device_node * np)1204 static void __iomem *cpm_uart_map_pram(struct uart_cpm_port *port,
1205 struct device_node *np)
1206 {
1207 void __iomem *pram;
1208 unsigned long offset;
1209 struct resource res;
1210 resource_size_t len;
1211
1212 /* Don't remap parameter RAM if it has already been initialized
1213 * during console setup.
1214 */
1215 if (IS_SMC(port) && port->smcup)
1216 return port->smcup;
1217 else if (!IS_SMC(port) && port->sccup)
1218 return port->sccup;
1219
1220 if (of_address_to_resource(np, 1, &res))
1221 return NULL;
1222
1223 len = resource_size(&res);
1224 pram = ioremap(res.start, len);
1225 if (!pram)
1226 return NULL;
1227
1228 if (!IS_ENABLED(CONFIG_CPM2) || !IS_SMC(port))
1229 return pram;
1230
1231 if (len != 2) {
1232 pr_warn("cpm_uart[%d]: device tree references "
1233 "SMC pram, using boot loader/wrapper pram mapping. "
1234 "Please fix your device tree to reference the pram "
1235 "base register instead.\n",
1236 port->port.line);
1237 return pram;
1238 }
1239
1240 offset = cpm_muram_alloc(64, 64);
1241 out_be16(pram, offset);
1242 iounmap(pram);
1243 return cpm_muram_addr(offset);
1244 }
1245
cpm_uart_unmap_pram(struct uart_cpm_port * port,void __iomem * pram)1246 static void cpm_uart_unmap_pram(struct uart_cpm_port *port, void __iomem *pram)
1247 {
1248 if (!IS_ENABLED(CONFIG_CPM2) || !IS_SMC(port))
1249 iounmap(pram);
1250 }
1251
cpm_uart_init_port(struct device_node * np,struct uart_cpm_port * pinfo)1252 static int cpm_uart_init_port(struct device_node *np,
1253 struct uart_cpm_port *pinfo)
1254 {
1255 const u32 *data;
1256 void __iomem *mem, *pram;
1257 struct device *dev = pinfo->port.dev;
1258 int len;
1259 int ret;
1260 int i;
1261
1262 data = of_get_property(np, "clock", NULL);
1263 if (data) {
1264 struct clk *clk = clk_get(NULL, (const char*)data);
1265 if (!IS_ERR(clk))
1266 pinfo->clk = clk;
1267 }
1268 if (!pinfo->clk) {
1269 data = of_get_property(np, "fsl,cpm-brg", &len);
1270 if (!data || len != 4) {
1271 printk(KERN_ERR "CPM UART %pOFn has no/invalid "
1272 "fsl,cpm-brg property.\n", np);
1273 return -EINVAL;
1274 }
1275 pinfo->brg = *data;
1276 }
1277
1278 data = of_get_property(np, "fsl,cpm-command", &len);
1279 if (!data || len != 4) {
1280 printk(KERN_ERR "CPM UART %pOFn has no/invalid "
1281 "fsl,cpm-command property.\n", np);
1282 return -EINVAL;
1283 }
1284 pinfo->command = *data;
1285
1286 mem = of_iomap(np, 0);
1287 if (!mem)
1288 return -ENOMEM;
1289
1290 if (of_device_is_compatible(np, "fsl,cpm1-scc-uart") ||
1291 of_device_is_compatible(np, "fsl,cpm2-scc-uart")) {
1292 pinfo->sccp = mem;
1293 pinfo->sccup = pram = cpm_uart_map_pram(pinfo, np);
1294 } else if (of_device_is_compatible(np, "fsl,cpm1-smc-uart") ||
1295 of_device_is_compatible(np, "fsl,cpm2-smc-uart")) {
1296 pinfo->flags |= FLAG_SMC;
1297 pinfo->smcp = mem;
1298 pinfo->smcup = pram = cpm_uart_map_pram(pinfo, np);
1299 } else {
1300 ret = -ENODEV;
1301 goto out_mem;
1302 }
1303
1304 if (!pram) {
1305 ret = -ENOMEM;
1306 goto out_mem;
1307 }
1308
1309 pinfo->tx_nrfifos = TX_NUM_FIFO;
1310 pinfo->tx_fifosize = TX_BUF_SIZE;
1311 pinfo->rx_nrfifos = RX_NUM_FIFO;
1312 pinfo->rx_fifosize = RX_BUF_SIZE;
1313
1314 pinfo->port.uartclk = ppc_proc_freq;
1315 pinfo->port.mapbase = (unsigned long)mem;
1316 pinfo->port.type = PORT_CPM;
1317 pinfo->port.ops = &cpm_uart_pops;
1318 pinfo->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_CPM_CONSOLE);
1319 pinfo->port.iotype = UPIO_MEM;
1320 pinfo->port.fifosize = pinfo->tx_nrfifos * pinfo->tx_fifosize;
1321 spin_lock_init(&pinfo->port.lock);
1322
1323 for (i = 0; i < NUM_GPIOS; i++) {
1324 struct gpio_desc *gpiod;
1325
1326 pinfo->gpios[i] = NULL;
1327
1328 gpiod = devm_gpiod_get_index_optional(dev, NULL, i, GPIOD_ASIS);
1329
1330 if (IS_ERR(gpiod)) {
1331 ret = PTR_ERR(gpiod);
1332 goto out_pram;
1333 }
1334
1335 if (gpiod) {
1336 if (i == GPIO_RTS || i == GPIO_DTR)
1337 ret = gpiod_direction_output(gpiod, 0);
1338 else
1339 ret = gpiod_direction_input(gpiod);
1340 if (ret) {
1341 pr_err("can't set direction for gpio #%d: %d\n",
1342 i, ret);
1343 continue;
1344 }
1345 pinfo->gpios[i] = gpiod;
1346 }
1347 }
1348
1349 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
1350 #if defined(CONFIG_CONSOLE_POLL) && defined(CONFIG_SERIAL_CPM_CONSOLE)
1351 if (!udbg_port)
1352 #endif
1353 udbg_putc = NULL;
1354 #endif
1355
1356 return cpm_uart_request_port(&pinfo->port);
1357
1358 out_pram:
1359 cpm_uart_unmap_pram(pinfo, pram);
1360 out_mem:
1361 iounmap(mem);
1362 return ret;
1363 }
1364
1365 #ifdef CONFIG_SERIAL_CPM_CONSOLE
1366 /*
1367 * Print a string to the serial port trying not to disturb
1368 * any possible real use of the port...
1369 *
1370 * Note that this is called with interrupts already disabled
1371 */
cpm_uart_console_write(struct console * co,const char * s,u_int count)1372 static void cpm_uart_console_write(struct console *co, const char *s,
1373 u_int count)
1374 {
1375 struct uart_cpm_port *pinfo = &cpm_uart_ports[co->index];
1376 unsigned long flags;
1377
1378 if (unlikely(oops_in_progress)) {
1379 local_irq_save(flags);
1380 cpm_uart_early_write(pinfo, s, count, true);
1381 local_irq_restore(flags);
1382 } else {
1383 uart_port_lock_irqsave(&pinfo->port, &flags);
1384 cpm_uart_early_write(pinfo, s, count, true);
1385 uart_port_unlock_irqrestore(&pinfo->port, flags);
1386 }
1387 }
1388
1389
cpm_uart_console_setup(struct console * co,char * options)1390 static int __init cpm_uart_console_setup(struct console *co, char *options)
1391 {
1392 int baud = 38400;
1393 int bits = 8;
1394 int parity = 'n';
1395 int flow = 'n';
1396 int ret;
1397 struct uart_cpm_port *pinfo;
1398 struct uart_port *port;
1399
1400 struct device_node *np;
1401 int i = 0;
1402
1403 if (co->index >= UART_NR) {
1404 printk(KERN_ERR "cpm_uart: console index %d too high\n",
1405 co->index);
1406 return -ENODEV;
1407 }
1408
1409 for_each_node_by_type(np, "serial") {
1410 if (!of_device_is_compatible(np, "fsl,cpm1-smc-uart") &&
1411 !of_device_is_compatible(np, "fsl,cpm1-scc-uart") &&
1412 !of_device_is_compatible(np, "fsl,cpm2-smc-uart") &&
1413 !of_device_is_compatible(np, "fsl,cpm2-scc-uart"))
1414 continue;
1415
1416 if (i++ == co->index)
1417 break;
1418 }
1419
1420 if (!np)
1421 return -ENODEV;
1422
1423 pinfo = &cpm_uart_ports[co->index];
1424
1425 pinfo->flags |= FLAG_CONSOLE;
1426 port = &pinfo->port;
1427
1428 ret = cpm_uart_init_port(np, pinfo);
1429 of_node_put(np);
1430 if (ret)
1431 return ret;
1432
1433 if (options) {
1434 uart_parse_options(options, &baud, &parity, &bits, &flow);
1435 } else {
1436 baud = get_baudrate();
1437 if (baud == -1)
1438 baud = 9600;
1439 }
1440
1441 if (IS_SMC(pinfo)) {
1442 out_be16(&pinfo->smcup->smc_brkcr, 0);
1443 cpm_line_cr_cmd(pinfo, CPM_CR_STOP_TX);
1444 clrbits8(&pinfo->smcp->smc_smcm, SMCM_RX | SMCM_TX);
1445 clrbits16(&pinfo->smcp->smc_smcmr, SMCMR_REN | SMCMR_TEN);
1446 } else {
1447 out_be16(&pinfo->sccup->scc_brkcr, 0);
1448 cpm_line_cr_cmd(pinfo, CPM_CR_GRA_STOP_TX);
1449 clrbits16(&pinfo->sccp->scc_sccm, UART_SCCM_TX | UART_SCCM_RX);
1450 clrbits32(&pinfo->sccp->scc_gsmrl, SCC_GSMRL_ENR | SCC_GSMRL_ENT);
1451 }
1452
1453 ret = cpm_uart_allocbuf(pinfo, 1);
1454
1455 if (ret)
1456 return ret;
1457
1458 cpm_uart_initbd(pinfo);
1459
1460 if (IS_SMC(pinfo))
1461 cpm_uart_init_smc(pinfo);
1462 else
1463 cpm_uart_init_scc(pinfo);
1464
1465 uart_set_options(port, co, baud, parity, bits, flow);
1466 cpm_line_cr_cmd(pinfo, CPM_CR_RESTART_TX);
1467
1468 #ifdef CONFIG_CONSOLE_POLL
1469 if (!udbg_port) {
1470 udbg_port = &pinfo->port;
1471 udbg_putc = udbg_cpm_putc;
1472 udbg_getc = udbg_cpm_getc;
1473 udbg_getc_poll = udbg_cpm_getc_poll;
1474 }
1475 #endif
1476
1477 return 0;
1478 }
1479
1480 static struct uart_driver cpm_reg;
1481 static struct console cpm_scc_uart_console = {
1482 .name = "ttyCPM",
1483 .write = cpm_uart_console_write,
1484 .device = uart_console_device,
1485 .setup = cpm_uart_console_setup,
1486 .flags = CON_PRINTBUFFER,
1487 .index = -1,
1488 .data = &cpm_reg,
1489 };
1490
cpm_uart_console_init(void)1491 static int __init cpm_uart_console_init(void)
1492 {
1493 cpm_muram_init();
1494 register_console(&cpm_scc_uart_console);
1495 return 0;
1496 }
1497
1498 console_initcall(cpm_uart_console_init);
1499
1500 #define CPM_UART_CONSOLE &cpm_scc_uart_console
1501 #else
1502 #define CPM_UART_CONSOLE NULL
1503 #endif
1504
1505 static struct uart_driver cpm_reg = {
1506 .owner = THIS_MODULE,
1507 .driver_name = "ttyCPM",
1508 .dev_name = "ttyCPM",
1509 .major = SERIAL_CPM_MAJOR,
1510 .minor = SERIAL_CPM_MINOR,
1511 .cons = CPM_UART_CONSOLE,
1512 .nr = UART_NR,
1513 };
1514
1515 static int probe_index;
1516
cpm_uart_probe(struct platform_device * ofdev)1517 static int cpm_uart_probe(struct platform_device *ofdev)
1518 {
1519 int index = probe_index++;
1520 struct uart_cpm_port *pinfo = &cpm_uart_ports[index];
1521 int ret;
1522
1523 pinfo->port.line = index;
1524
1525 if (index >= UART_NR)
1526 return -ENODEV;
1527
1528 platform_set_drvdata(ofdev, pinfo);
1529
1530 /* initialize the device pointer for the port */
1531 pinfo->port.dev = &ofdev->dev;
1532
1533 pinfo->port.irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
1534 if (!pinfo->port.irq)
1535 return -EINVAL;
1536
1537 ret = cpm_uart_init_port(ofdev->dev.of_node, pinfo);
1538 if (!ret)
1539 return uart_add_one_port(&cpm_reg, &pinfo->port);
1540
1541 irq_dispose_mapping(pinfo->port.irq);
1542
1543 return ret;
1544 }
1545
cpm_uart_remove(struct platform_device * ofdev)1546 static void cpm_uart_remove(struct platform_device *ofdev)
1547 {
1548 struct uart_cpm_port *pinfo = platform_get_drvdata(ofdev);
1549
1550 uart_remove_one_port(&cpm_reg, &pinfo->port);
1551 }
1552
1553 static const struct of_device_id cpm_uart_match[] = {
1554 {
1555 .compatible = "fsl,cpm1-smc-uart",
1556 },
1557 {
1558 .compatible = "fsl,cpm1-scc-uart",
1559 },
1560 {
1561 .compatible = "fsl,cpm2-smc-uart",
1562 },
1563 {
1564 .compatible = "fsl,cpm2-scc-uart",
1565 },
1566 {}
1567 };
1568 MODULE_DEVICE_TABLE(of, cpm_uart_match);
1569
1570 static struct platform_driver cpm_uart_driver = {
1571 .driver = {
1572 .name = "cpm_uart",
1573 .of_match_table = cpm_uart_match,
1574 },
1575 .probe = cpm_uart_probe,
1576 .remove = cpm_uart_remove,
1577 };
1578
cpm_uart_init(void)1579 static int __init cpm_uart_init(void)
1580 {
1581 int ret = uart_register_driver(&cpm_reg);
1582 if (ret)
1583 return ret;
1584
1585 ret = platform_driver_register(&cpm_uart_driver);
1586 if (ret)
1587 uart_unregister_driver(&cpm_reg);
1588
1589 return ret;
1590 }
1591
cpm_uart_exit(void)1592 static void __exit cpm_uart_exit(void)
1593 {
1594 platform_driver_unregister(&cpm_uart_driver);
1595 uart_unregister_driver(&cpm_reg);
1596 }
1597
1598 module_init(cpm_uart_init);
1599 module_exit(cpm_uart_exit);
1600
1601 MODULE_AUTHOR("Kumar Gala/Antoniou Pantelis");
1602 MODULE_DESCRIPTION("CPM SCC/SMC port driver $Revision: 0.01 $");
1603 MODULE_LICENSE("GPL");
1604 MODULE_ALIAS_CHARDEV(SERIAL_CPM_MAJOR, SERIAL_CPM_MINOR);
1605