1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
3 
4 #if defined(CONFIG_SERIAL_QCOM_GENI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
5 # define SUPPORT_SYSRQ
6 #endif
7 
8 #include <linux/clk.h>
9 #include <linux/console.h>
10 #include <linux/io.h>
11 #include <linux/iopoll.h>
12 #include <linux/irq.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_device.h>
16 #include <linux/platform_device.h>
17 #include <linux/pm_wakeirq.h>
18 #include <linux/qcom-geni-se.h>
19 #include <linux/serial.h>
20 #include <linux/serial_core.h>
21 #include <linux/slab.h>
22 #include <linux/tty.h>
23 #include <linux/tty_flip.h>
24 
25 /* UART specific GENI registers */
26 #define SE_UART_LOOPBACK_CFG		0x22c
27 #define SE_UART_TX_TRANS_CFG		0x25c
28 #define SE_UART_TX_WORD_LEN		0x268
29 #define SE_UART_TX_STOP_BIT_LEN		0x26c
30 #define SE_UART_TX_TRANS_LEN		0x270
31 #define SE_UART_RX_TRANS_CFG		0x280
32 #define SE_UART_RX_WORD_LEN		0x28c
33 #define SE_UART_RX_STALE_CNT		0x294
34 #define SE_UART_TX_PARITY_CFG		0x2a4
35 #define SE_UART_RX_PARITY_CFG		0x2a8
36 #define SE_UART_MANUAL_RFR		0x2ac
37 
38 /* SE_UART_TRANS_CFG */
39 #define UART_TX_PAR_EN		BIT(0)
40 #define UART_CTS_MASK		BIT(1)
41 
42 /* SE_UART_TX_WORD_LEN */
43 #define TX_WORD_LEN_MSK		GENMASK(9, 0)
44 
45 /* SE_UART_TX_STOP_BIT_LEN */
46 #define TX_STOP_BIT_LEN_MSK	GENMASK(23, 0)
47 #define TX_STOP_BIT_LEN_1	0
48 #define TX_STOP_BIT_LEN_1_5	1
49 #define TX_STOP_BIT_LEN_2	2
50 
51 /* SE_UART_TX_TRANS_LEN */
52 #define TX_TRANS_LEN_MSK	GENMASK(23, 0)
53 
54 /* SE_UART_RX_TRANS_CFG */
55 #define UART_RX_INS_STATUS_BIT	BIT(2)
56 #define UART_RX_PAR_EN		BIT(3)
57 
58 /* SE_UART_RX_WORD_LEN */
59 #define RX_WORD_LEN_MASK	GENMASK(9, 0)
60 
61 /* SE_UART_RX_STALE_CNT */
62 #define RX_STALE_CNT		GENMASK(23, 0)
63 
64 /* SE_UART_TX_PARITY_CFG/RX_PARITY_CFG */
65 #define PAR_CALC_EN		BIT(0)
66 #define PAR_MODE_MSK		GENMASK(2, 1)
67 #define PAR_MODE_SHFT		1
68 #define PAR_EVEN		0x00
69 #define PAR_ODD			0x01
70 #define PAR_SPACE		0x10
71 #define PAR_MARK		0x11
72 
73 /* SE_UART_MANUAL_RFR register fields */
74 #define UART_MANUAL_RFR_EN	BIT(31)
75 #define UART_RFR_NOT_READY	BIT(1)
76 #define UART_RFR_READY		BIT(0)
77 
78 /* UART M_CMD OP codes */
79 #define UART_START_TX		0x1
80 #define UART_START_BREAK	0x4
81 #define UART_STOP_BREAK		0x5
82 /* UART S_CMD OP codes */
83 #define UART_START_READ		0x1
84 #define UART_PARAM		0x1
85 
86 #define UART_OVERSAMPLING	32
87 #define STALE_TIMEOUT		16
88 #define DEFAULT_BITS_PER_CHAR	10
89 #define GENI_UART_CONS_PORTS	1
90 #define GENI_UART_PORTS		3
91 #define DEF_FIFO_DEPTH_WORDS	16
92 #define DEF_TX_WM		2
93 #define DEF_FIFO_WIDTH_BITS	32
94 #define UART_RX_WM		2
95 #define MAX_LOOPBACK_CFG	3
96 
97 #ifdef CONFIG_CONSOLE_POLL
98 #define CONSOLE_RX_BYTES_PW 1
99 #else
100 #define CONSOLE_RX_BYTES_PW 4
101 #endif
102 
103 struct qcom_geni_serial_port {
104 	struct uart_port uport;
105 	struct geni_se se;
106 	char name[20];
107 	u32 tx_fifo_depth;
108 	u32 tx_fifo_width;
109 	u32 rx_fifo_depth;
110 	bool setup;
111 	int (*handle_rx)(struct uart_port *uport, u32 bytes, bool drop);
112 	unsigned int baud;
113 	unsigned int tx_bytes_pw;
114 	unsigned int rx_bytes_pw;
115 	u32 *rx_fifo;
116 	u32 loopback;
117 	bool brk;
118 
119 	unsigned int tx_remaining;
120 	int wakeup_irq;
121 };
122 
123 static const struct uart_ops qcom_geni_console_pops;
124 static const struct uart_ops qcom_geni_uart_pops;
125 static struct uart_driver qcom_geni_console_driver;
126 static struct uart_driver qcom_geni_uart_driver;
127 static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop);
128 static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop);
129 static unsigned int qcom_geni_serial_tx_empty(struct uart_port *port);
130 static void qcom_geni_serial_stop_rx(struct uart_port *uport);
131 
132 static const unsigned long root_freq[] = {7372800, 14745600, 19200000, 29491200,
133 					32000000, 48000000, 64000000, 80000000,
134 					96000000, 100000000, 102400000,
135 					112000000, 120000000, 128000000};
136 
137 #define to_dev_port(ptr, member) \
138 		container_of(ptr, struct qcom_geni_serial_port, member)
139 
140 static struct qcom_geni_serial_port qcom_geni_uart_ports[GENI_UART_PORTS] = {
141 	[0] = {
142 		.uport = {
143 				.iotype = UPIO_MEM,
144 				.ops = &qcom_geni_uart_pops,
145 				.flags = UPF_BOOT_AUTOCONF,
146 				.line = 0,
147 		},
148 	},
149 	[1] = {
150 		.uport = {
151 				.iotype = UPIO_MEM,
152 				.ops = &qcom_geni_uart_pops,
153 				.flags = UPF_BOOT_AUTOCONF,
154 				.line = 1,
155 		},
156 	},
157 	[2] = {
158 		.uport = {
159 				.iotype = UPIO_MEM,
160 				.ops = &qcom_geni_uart_pops,
161 				.flags = UPF_BOOT_AUTOCONF,
162 				.line = 2,
163 		},
164 	},
165 };
166 
167 static ssize_t loopback_show(struct device *dev,
168 				struct device_attribute *attr, char *buf)
169 {
170 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
171 
172 	return snprintf(buf, sizeof(u32), "%d\n", port->loopback);
173 }
174 
175 static ssize_t loopback_store(struct device *dev,
176 				struct device_attribute *attr, const char *buf,
177 				size_t size)
178 {
179 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
180 	u32 loopback;
181 
182 	if (kstrtoint(buf, 0, &loopback) || loopback > MAX_LOOPBACK_CFG) {
183 		dev_err(dev, "Invalid input\n");
184 		return -EINVAL;
185 	}
186 	port->loopback = loopback;
187 	return size;
188 }
189 static DEVICE_ATTR_RW(loopback);
190 
191 static struct qcom_geni_serial_port qcom_geni_console_port = {
192 	.uport = {
193 		.iotype = UPIO_MEM,
194 		.ops = &qcom_geni_console_pops,
195 		.flags = UPF_BOOT_AUTOCONF,
196 		.line = 0,
197 	},
198 };
199 
200 static int qcom_geni_serial_request_port(struct uart_port *uport)
201 {
202 	struct platform_device *pdev = to_platform_device(uport->dev);
203 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
204 
205 	uport->membase = devm_platform_ioremap_resource(pdev, 0);
206 	if (IS_ERR(uport->membase))
207 		return PTR_ERR(uport->membase);
208 	port->se.base = uport->membase;
209 	return 0;
210 }
211 
212 static void qcom_geni_serial_config_port(struct uart_port *uport, int cfg_flags)
213 {
214 	if (cfg_flags & UART_CONFIG_TYPE) {
215 		uport->type = PORT_MSM;
216 		qcom_geni_serial_request_port(uport);
217 	}
218 }
219 
220 static unsigned int qcom_geni_serial_get_mctrl(struct uart_port *uport)
221 {
222 	unsigned int mctrl = TIOCM_DSR | TIOCM_CAR;
223 	u32 geni_ios;
224 
225 	if (uart_console(uport)) {
226 		mctrl |= TIOCM_CTS;
227 	} else {
228 		geni_ios = readl(uport->membase + SE_GENI_IOS);
229 		if (!(geni_ios & IO2_DATA_IN))
230 			mctrl |= TIOCM_CTS;
231 	}
232 
233 	return mctrl;
234 }
235 
236 static void qcom_geni_serial_set_mctrl(struct uart_port *uport,
237 							unsigned int mctrl)
238 {
239 	u32 uart_manual_rfr = 0;
240 
241 	if (uart_console(uport))
242 		return;
243 
244 	if (!(mctrl & TIOCM_RTS))
245 		uart_manual_rfr = UART_MANUAL_RFR_EN | UART_RFR_NOT_READY;
246 	writel(uart_manual_rfr, uport->membase + SE_UART_MANUAL_RFR);
247 }
248 
249 static const char *qcom_geni_serial_get_type(struct uart_port *uport)
250 {
251 	return "MSM";
252 }
253 
254 static struct qcom_geni_serial_port *get_port_from_line(int line, bool console)
255 {
256 	struct qcom_geni_serial_port *port;
257 	int nr_ports = console ? GENI_UART_CONS_PORTS : GENI_UART_PORTS;
258 
259 	if (line < 0 || line >= nr_ports)
260 		return ERR_PTR(-ENXIO);
261 
262 	port = console ? &qcom_geni_console_port : &qcom_geni_uart_ports[line];
263 	return port;
264 }
265 
266 static bool qcom_geni_serial_poll_bit(struct uart_port *uport,
267 				int offset, int field, bool set)
268 {
269 	u32 reg;
270 	struct qcom_geni_serial_port *port;
271 	unsigned int baud;
272 	unsigned int fifo_bits;
273 	unsigned long timeout_us = 20000;
274 
275 	if (uport->private_data) {
276 		port = to_dev_port(uport, uport);
277 		baud = port->baud;
278 		if (!baud)
279 			baud = 115200;
280 		fifo_bits = port->tx_fifo_depth * port->tx_fifo_width;
281 		/*
282 		 * Total polling iterations based on FIFO worth of bytes to be
283 		 * sent at current baud. Add a little fluff to the wait.
284 		 */
285 		timeout_us = ((fifo_bits * USEC_PER_SEC) / baud) + 500;
286 	}
287 
288 	/*
289 	 * Use custom implementation instead of readl_poll_atomic since ktimer
290 	 * is not ready at the time of early console.
291 	 */
292 	timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10;
293 	while (timeout_us) {
294 		reg = readl(uport->membase + offset);
295 		if ((bool)(reg & field) == set)
296 			return true;
297 		udelay(10);
298 		timeout_us -= 10;
299 	}
300 	return false;
301 }
302 
303 static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size)
304 {
305 	u32 m_cmd;
306 
307 	writel(xmit_size, uport->membase + SE_UART_TX_TRANS_LEN);
308 	m_cmd = UART_START_TX << M_OPCODE_SHFT;
309 	writel(m_cmd, uport->membase + SE_GENI_M_CMD0);
310 }
311 
312 static void qcom_geni_serial_poll_tx_done(struct uart_port *uport)
313 {
314 	int done;
315 	u32 irq_clear = M_CMD_DONE_EN;
316 
317 	done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
318 						M_CMD_DONE_EN, true);
319 	if (!done) {
320 		writel(M_GENI_CMD_ABORT, uport->membase +
321 						SE_GENI_M_CMD_CTRL_REG);
322 		irq_clear |= M_CMD_ABORT_EN;
323 		qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
324 							M_CMD_ABORT_EN, true);
325 	}
326 	writel(irq_clear, uport->membase + SE_GENI_M_IRQ_CLEAR);
327 }
328 
329 static void qcom_geni_serial_abort_rx(struct uart_port *uport)
330 {
331 	u32 irq_clear = S_CMD_DONE_EN | S_CMD_ABORT_EN;
332 
333 	writel(S_GENI_CMD_ABORT, uport->membase + SE_GENI_S_CMD_CTRL_REG);
334 	qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG,
335 					S_GENI_CMD_ABORT, false);
336 	writel(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR);
337 	writel(FORCE_DEFAULT, uport->membase + GENI_FORCE_DEFAULT_REG);
338 }
339 
340 #ifdef CONFIG_CONSOLE_POLL
341 static int qcom_geni_serial_get_char(struct uart_port *uport)
342 {
343 	u32 rx_fifo;
344 	u32 status;
345 
346 	status = readl(uport->membase + SE_GENI_M_IRQ_STATUS);
347 	writel(status, uport->membase + SE_GENI_M_IRQ_CLEAR);
348 
349 	status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
350 	writel(status, uport->membase + SE_GENI_S_IRQ_CLEAR);
351 
352 	status = readl(uport->membase + SE_GENI_RX_FIFO_STATUS);
353 	if (!(status & RX_FIFO_WC_MSK))
354 		return NO_POLL_CHAR;
355 
356 	rx_fifo = readl(uport->membase + SE_GENI_RX_FIFOn);
357 	return rx_fifo & 0xff;
358 }
359 
360 static void qcom_geni_serial_poll_put_char(struct uart_port *uport,
361 							unsigned char c)
362 {
363 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
364 	qcom_geni_serial_setup_tx(uport, 1);
365 	WARN_ON(!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
366 						M_TX_FIFO_WATERMARK_EN, true));
367 	writel(c, uport->membase + SE_GENI_TX_FIFOn);
368 	writel(M_TX_FIFO_WATERMARK_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
369 	qcom_geni_serial_poll_tx_done(uport);
370 }
371 #endif
372 
373 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
374 static void qcom_geni_serial_wr_char(struct uart_port *uport, int ch)
375 {
376 	writel(ch, uport->membase + SE_GENI_TX_FIFOn);
377 }
378 
379 static void
380 __qcom_geni_serial_console_write(struct uart_port *uport, const char *s,
381 				 unsigned int count)
382 {
383 	int i;
384 	u32 bytes_to_send = count;
385 
386 	for (i = 0; i < count; i++) {
387 		/*
388 		 * uart_console_write() adds a carriage return for each newline.
389 		 * Account for additional bytes to be written.
390 		 */
391 		if (s[i] == '\n')
392 			bytes_to_send++;
393 	}
394 
395 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
396 	qcom_geni_serial_setup_tx(uport, bytes_to_send);
397 	for (i = 0; i < count; ) {
398 		size_t chars_to_write = 0;
399 		size_t avail = DEF_FIFO_DEPTH_WORDS - DEF_TX_WM;
400 
401 		/*
402 		 * If the WM bit never set, then the Tx state machine is not
403 		 * in a valid state, so break, cancel/abort any existing
404 		 * command. Unfortunately the current data being written is
405 		 * lost.
406 		 */
407 		if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
408 						M_TX_FIFO_WATERMARK_EN, true))
409 			break;
410 		chars_to_write = min_t(size_t, count - i, avail / 2);
411 		uart_console_write(uport, s + i, chars_to_write,
412 						qcom_geni_serial_wr_char);
413 		writel(M_TX_FIFO_WATERMARK_EN, uport->membase +
414 							SE_GENI_M_IRQ_CLEAR);
415 		i += chars_to_write;
416 	}
417 	qcom_geni_serial_poll_tx_done(uport);
418 }
419 
420 static void qcom_geni_serial_console_write(struct console *co, const char *s,
421 			      unsigned int count)
422 {
423 	struct uart_port *uport;
424 	struct qcom_geni_serial_port *port;
425 	bool locked = true;
426 	unsigned long flags;
427 	u32 geni_status;
428 	u32 irq_en;
429 
430 	WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS);
431 
432 	port = get_port_from_line(co->index, true);
433 	if (IS_ERR(port))
434 		return;
435 
436 	uport = &port->uport;
437 	if (oops_in_progress)
438 		locked = spin_trylock_irqsave(&uport->lock, flags);
439 	else
440 		spin_lock_irqsave(&uport->lock, flags);
441 
442 	geni_status = readl(uport->membase + SE_GENI_STATUS);
443 
444 	/* Cancel the current write to log the fault */
445 	if (!locked) {
446 		geni_se_cancel_m_cmd(&port->se);
447 		if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
448 						M_CMD_CANCEL_EN, true)) {
449 			geni_se_abort_m_cmd(&port->se);
450 			qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
451 							M_CMD_ABORT_EN, true);
452 			writel(M_CMD_ABORT_EN, uport->membase +
453 							SE_GENI_M_IRQ_CLEAR);
454 		}
455 		writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
456 	} else if ((geni_status & M_GENI_CMD_ACTIVE) && !port->tx_remaining) {
457 		/*
458 		 * It seems we can't interrupt existing transfers if all data
459 		 * has been sent, in which case we need to look for done first.
460 		 */
461 		qcom_geni_serial_poll_tx_done(uport);
462 
463 		if (uart_circ_chars_pending(&uport->state->xmit)) {
464 			irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
465 			writel(irq_en | M_TX_FIFO_WATERMARK_EN,
466 					uport->membase + SE_GENI_M_IRQ_EN);
467 		}
468 	}
469 
470 	__qcom_geni_serial_console_write(uport, s, count);
471 
472 	if (port->tx_remaining)
473 		qcom_geni_serial_setup_tx(uport, port->tx_remaining);
474 
475 	if (locked)
476 		spin_unlock_irqrestore(&uport->lock, flags);
477 }
478 
479 static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
480 {
481 	u32 i;
482 	unsigned char buf[sizeof(u32)];
483 	struct tty_port *tport;
484 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
485 
486 	tport = &uport->state->port;
487 	for (i = 0; i < bytes; ) {
488 		int c;
489 		int chunk = min_t(int, bytes - i, port->rx_bytes_pw);
490 
491 		ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1);
492 		i += chunk;
493 		if (drop)
494 			continue;
495 
496 		for (c = 0; c < chunk; c++) {
497 			int sysrq;
498 
499 			uport->icount.rx++;
500 			if (port->brk && buf[c] == 0) {
501 				port->brk = false;
502 				if (uart_handle_break(uport))
503 					continue;
504 			}
505 
506 			sysrq = uart_prepare_sysrq_char(uport, buf[c]);
507 
508 			if (!sysrq)
509 				tty_insert_flip_char(tport, buf[c], TTY_NORMAL);
510 		}
511 	}
512 	if (!drop)
513 		tty_flip_buffer_push(tport);
514 	return 0;
515 }
516 #else
517 static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
518 {
519 	return -EPERM;
520 }
521 
522 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
523 
524 static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop)
525 {
526 	unsigned char *buf;
527 	struct tty_port *tport;
528 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
529 	u32 num_bytes_pw = port->tx_fifo_width / BITS_PER_BYTE;
530 	u32 words = ALIGN(bytes, num_bytes_pw) / num_bytes_pw;
531 	int ret;
532 
533 	tport = &uport->state->port;
534 	ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, port->rx_fifo, words);
535 	if (drop)
536 		return 0;
537 
538 	buf = (unsigned char *)port->rx_fifo;
539 	ret = tty_insert_flip_string(tport, buf, bytes);
540 	if (ret != bytes) {
541 		dev_err(uport->dev, "%s:Unable to push data ret %d_bytes %d\n",
542 				__func__, ret, bytes);
543 		WARN_ON_ONCE(1);
544 	}
545 	uport->icount.rx += ret;
546 	tty_flip_buffer_push(tport);
547 	return ret;
548 }
549 
550 static void qcom_geni_serial_start_tx(struct uart_port *uport)
551 {
552 	u32 irq_en;
553 	u32 status;
554 
555 	status = readl(uport->membase + SE_GENI_STATUS);
556 	if (status & M_GENI_CMD_ACTIVE)
557 		return;
558 
559 	if (!qcom_geni_serial_tx_empty(uport))
560 		return;
561 
562 	irq_en = readl(uport->membase +	SE_GENI_M_IRQ_EN);
563 	irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
564 
565 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
566 	writel(irq_en, uport->membase +	SE_GENI_M_IRQ_EN);
567 }
568 
569 static void qcom_geni_serial_stop_tx(struct uart_port *uport)
570 {
571 	u32 irq_en;
572 	u32 status;
573 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
574 
575 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
576 	irq_en &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
577 	writel(0, uport->membase + SE_GENI_TX_WATERMARK_REG);
578 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
579 	status = readl(uport->membase + SE_GENI_STATUS);
580 	/* Possible stop tx is called multiple times. */
581 	if (!(status & M_GENI_CMD_ACTIVE))
582 		return;
583 
584 	geni_se_cancel_m_cmd(&port->se);
585 	if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
586 						M_CMD_CANCEL_EN, true)) {
587 		geni_se_abort_m_cmd(&port->se);
588 		qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
589 						M_CMD_ABORT_EN, true);
590 		writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
591 	}
592 	writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
593 }
594 
595 static void qcom_geni_serial_start_rx(struct uart_port *uport)
596 {
597 	u32 irq_en;
598 	u32 status;
599 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
600 
601 	status = readl(uport->membase + SE_GENI_STATUS);
602 	if (status & S_GENI_CMD_ACTIVE)
603 		qcom_geni_serial_stop_rx(uport);
604 
605 	geni_se_setup_s_cmd(&port->se, UART_START_READ, 0);
606 
607 	irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
608 	irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN;
609 	writel(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
610 
611 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
612 	irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
613 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
614 }
615 
616 static void qcom_geni_serial_stop_rx(struct uart_port *uport)
617 {
618 	u32 irq_en;
619 	u32 status;
620 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
621 	u32 irq_clear = S_CMD_DONE_EN;
622 
623 	irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
624 	irq_en &= ~(S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN);
625 	writel(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
626 
627 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
628 	irq_en &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
629 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
630 
631 	status = readl(uport->membase + SE_GENI_STATUS);
632 	/* Possible stop rx is called multiple times. */
633 	if (!(status & S_GENI_CMD_ACTIVE))
634 		return;
635 
636 	geni_se_cancel_s_cmd(&port->se);
637 	qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG,
638 					S_GENI_CMD_CANCEL, false);
639 	status = readl(uport->membase + SE_GENI_STATUS);
640 	writel(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR);
641 	if (status & S_GENI_CMD_ACTIVE)
642 		qcom_geni_serial_abort_rx(uport);
643 }
644 
645 static void qcom_geni_serial_handle_rx(struct uart_port *uport, bool drop)
646 {
647 	u32 status;
648 	u32 word_cnt;
649 	u32 last_word_byte_cnt;
650 	u32 last_word_partial;
651 	u32 total_bytes;
652 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
653 
654 	status = readl(uport->membase +	SE_GENI_RX_FIFO_STATUS);
655 	word_cnt = status & RX_FIFO_WC_MSK;
656 	last_word_partial = status & RX_LAST;
657 	last_word_byte_cnt = (status & RX_LAST_BYTE_VALID_MSK) >>
658 						RX_LAST_BYTE_VALID_SHFT;
659 
660 	if (!word_cnt)
661 		return;
662 	total_bytes = port->rx_bytes_pw * (word_cnt - 1);
663 	if (last_word_partial && last_word_byte_cnt)
664 		total_bytes += last_word_byte_cnt;
665 	else
666 		total_bytes += port->rx_bytes_pw;
667 	port->handle_rx(uport, total_bytes, drop);
668 }
669 
670 static void qcom_geni_serial_handle_tx(struct uart_port *uport, bool done,
671 		bool active)
672 {
673 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
674 	struct circ_buf *xmit = &uport->state->xmit;
675 	size_t avail;
676 	size_t remaining;
677 	size_t pending;
678 	int i;
679 	u32 status;
680 	u32 irq_en;
681 	unsigned int chunk;
682 	int tail;
683 
684 	status = readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
685 
686 	/* Complete the current tx command before taking newly added data */
687 	if (active)
688 		pending = port->tx_remaining;
689 	else
690 		pending = uart_circ_chars_pending(xmit);
691 
692 	/* All data has been transmitted and acknowledged as received */
693 	if (!pending && !status && done) {
694 		qcom_geni_serial_stop_tx(uport);
695 		goto out_write_wakeup;
696 	}
697 
698 	avail = port->tx_fifo_depth - (status & TX_FIFO_WC);
699 	avail *= port->tx_bytes_pw;
700 
701 	tail = xmit->tail;
702 	chunk = min(avail, pending);
703 	if (!chunk)
704 		goto out_write_wakeup;
705 
706 	if (!port->tx_remaining) {
707 		qcom_geni_serial_setup_tx(uport, pending);
708 		port->tx_remaining = pending;
709 
710 		irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
711 		if (!(irq_en & M_TX_FIFO_WATERMARK_EN))
712 			writel(irq_en | M_TX_FIFO_WATERMARK_EN,
713 					uport->membase + SE_GENI_M_IRQ_EN);
714 	}
715 
716 	remaining = chunk;
717 	for (i = 0; i < chunk; ) {
718 		unsigned int tx_bytes;
719 		u8 buf[sizeof(u32)];
720 		int c;
721 
722 		memset(buf, 0, ARRAY_SIZE(buf));
723 		tx_bytes = min_t(size_t, remaining, port->tx_bytes_pw);
724 
725 		for (c = 0; c < tx_bytes ; c++) {
726 			buf[c] = xmit->buf[tail++];
727 			tail &= UART_XMIT_SIZE - 1;
728 		}
729 
730 		iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
731 
732 		i += tx_bytes;
733 		uport->icount.tx += tx_bytes;
734 		remaining -= tx_bytes;
735 		port->tx_remaining -= tx_bytes;
736 	}
737 
738 	xmit->tail = tail;
739 
740 	/*
741 	 * The tx fifo watermark is level triggered and latched. Though we had
742 	 * cleared it in qcom_geni_serial_isr it will have already reasserted
743 	 * so we must clear it again here after our writes.
744 	 */
745 	writel(M_TX_FIFO_WATERMARK_EN,
746 			uport->membase + SE_GENI_M_IRQ_CLEAR);
747 
748 out_write_wakeup:
749 	if (!port->tx_remaining) {
750 		irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
751 		if (irq_en & M_TX_FIFO_WATERMARK_EN)
752 			writel(irq_en & ~M_TX_FIFO_WATERMARK_EN,
753 					uport->membase + SE_GENI_M_IRQ_EN);
754 	}
755 
756 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
757 		uart_write_wakeup(uport);
758 }
759 
760 static irqreturn_t qcom_geni_serial_wakeup_isr(int isr, void *dev)
761 {
762 	struct uart_port *uport = dev;
763 
764 	pm_wakeup_event(uport->dev, 2000);
765 
766 	return IRQ_HANDLED;
767 }
768 
769 static irqreturn_t qcom_geni_serial_isr(int isr, void *dev)
770 {
771 	u32 m_irq_en;
772 	u32 m_irq_status;
773 	u32 s_irq_status;
774 	u32 geni_status;
775 	struct uart_port *uport = dev;
776 	unsigned long flags;
777 	bool drop_rx = false;
778 	struct tty_port *tport = &uport->state->port;
779 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
780 
781 	if (uport->suspended)
782 		return IRQ_NONE;
783 
784 	spin_lock_irqsave(&uport->lock, flags);
785 	m_irq_status = readl(uport->membase + SE_GENI_M_IRQ_STATUS);
786 	s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
787 	geni_status = readl(uport->membase + SE_GENI_STATUS);
788 	m_irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
789 	writel(m_irq_status, uport->membase + SE_GENI_M_IRQ_CLEAR);
790 	writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
791 
792 	if (WARN_ON(m_irq_status & M_ILLEGAL_CMD_EN))
793 		goto out_unlock;
794 
795 	if (s_irq_status & S_RX_FIFO_WR_ERR_EN) {
796 		uport->icount.overrun++;
797 		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
798 	}
799 
800 	if (m_irq_status & m_irq_en & (M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN))
801 		qcom_geni_serial_handle_tx(uport, m_irq_status & M_CMD_DONE_EN,
802 					geni_status & M_GENI_CMD_ACTIVE);
803 
804 	if (s_irq_status & S_GP_IRQ_0_EN || s_irq_status & S_GP_IRQ_1_EN) {
805 		if (s_irq_status & S_GP_IRQ_0_EN)
806 			uport->icount.parity++;
807 		drop_rx = true;
808 	} else if (s_irq_status & S_GP_IRQ_2_EN ||
809 					s_irq_status & S_GP_IRQ_3_EN) {
810 		uport->icount.brk++;
811 		port->brk = true;
812 	}
813 
814 	if (s_irq_status & S_RX_FIFO_WATERMARK_EN ||
815 					s_irq_status & S_RX_FIFO_LAST_EN)
816 		qcom_geni_serial_handle_rx(uport, drop_rx);
817 
818 out_unlock:
819 	uart_unlock_and_check_sysrq(uport, flags);
820 
821 	return IRQ_HANDLED;
822 }
823 
824 static void get_tx_fifo_size(struct qcom_geni_serial_port *port)
825 {
826 	struct uart_port *uport;
827 
828 	uport = &port->uport;
829 	port->tx_fifo_depth = geni_se_get_tx_fifo_depth(&port->se);
830 	port->tx_fifo_width = geni_se_get_tx_fifo_width(&port->se);
831 	port->rx_fifo_depth = geni_se_get_rx_fifo_depth(&port->se);
832 	uport->fifosize =
833 		(port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE;
834 }
835 
836 
837 static void qcom_geni_serial_shutdown(struct uart_port *uport)
838 {
839 	unsigned long flags;
840 
841 	/* Stop the console before stopping the current tx */
842 	if (uart_console(uport))
843 		console_stop(uport->cons);
844 
845 	disable_irq(uport->irq);
846 	spin_lock_irqsave(&uport->lock, flags);
847 	qcom_geni_serial_stop_tx(uport);
848 	qcom_geni_serial_stop_rx(uport);
849 	spin_unlock_irqrestore(&uport->lock, flags);
850 }
851 
852 static int qcom_geni_serial_port_setup(struct uart_port *uport)
853 {
854 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
855 	u32 rxstale = DEFAULT_BITS_PER_CHAR * STALE_TIMEOUT;
856 	u32 proto;
857 
858 	if (uart_console(uport)) {
859 		port->tx_bytes_pw = 1;
860 		port->rx_bytes_pw = CONSOLE_RX_BYTES_PW;
861 	} else {
862 		port->tx_bytes_pw = 4;
863 		port->rx_bytes_pw = 4;
864 	}
865 
866 	proto = geni_se_read_proto(&port->se);
867 	if (proto != GENI_SE_UART) {
868 		dev_err(uport->dev, "Invalid FW loaded, proto: %d\n", proto);
869 		return -ENXIO;
870 	}
871 
872 	qcom_geni_serial_stop_rx(uport);
873 
874 	get_tx_fifo_size(port);
875 
876 	writel(rxstale, uport->membase + SE_UART_RX_STALE_CNT);
877 	/*
878 	 * Make an unconditional cancel on the main sequencer to reset
879 	 * it else we could end up in data loss scenarios.
880 	 */
881 	if (uart_console(uport))
882 		qcom_geni_serial_poll_tx_done(uport);
883 	geni_se_config_packing(&port->se, BITS_PER_BYTE, port->tx_bytes_pw,
884 						false, true, false);
885 	geni_se_config_packing(&port->se, BITS_PER_BYTE, port->rx_bytes_pw,
886 						false, false, true);
887 	geni_se_init(&port->se, UART_RX_WM, port->rx_fifo_depth - 2);
888 	geni_se_select_mode(&port->se, GENI_SE_FIFO);
889 	if (!uart_console(uport)) {
890 		port->rx_fifo = devm_kcalloc(uport->dev,
891 			port->rx_fifo_depth, sizeof(u32), GFP_KERNEL);
892 		if (!port->rx_fifo)
893 			return -ENOMEM;
894 	}
895 	port->setup = true;
896 
897 	return 0;
898 }
899 
900 static int qcom_geni_serial_startup(struct uart_port *uport)
901 {
902 	int ret;
903 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
904 
905 	if (!port->setup) {
906 		ret = qcom_geni_serial_port_setup(uport);
907 		if (ret)
908 			return ret;
909 	}
910 	enable_irq(uport->irq);
911 
912 	return 0;
913 }
914 
915 static unsigned long get_clk_cfg(unsigned long clk_freq)
916 {
917 	int i;
918 
919 	for (i = 0; i < ARRAY_SIZE(root_freq); i++) {
920 		if (!(root_freq[i] % clk_freq))
921 			return root_freq[i];
922 	}
923 	return 0;
924 }
925 
926 static unsigned long get_clk_div_rate(unsigned int baud,
927 			unsigned int sampling_rate, unsigned int *clk_div)
928 {
929 	unsigned long ser_clk;
930 	unsigned long desired_clk;
931 
932 	desired_clk = baud * sampling_rate;
933 	ser_clk = get_clk_cfg(desired_clk);
934 	if (!ser_clk) {
935 		pr_err("%s: Can't find matching DFS entry for baud %d\n",
936 								__func__, baud);
937 		return ser_clk;
938 	}
939 
940 	*clk_div = ser_clk / desired_clk;
941 	return ser_clk;
942 }
943 
944 static void qcom_geni_serial_set_termios(struct uart_port *uport,
945 				struct ktermios *termios, struct ktermios *old)
946 {
947 	unsigned int baud;
948 	u32 bits_per_char;
949 	u32 tx_trans_cfg;
950 	u32 tx_parity_cfg;
951 	u32 rx_trans_cfg;
952 	u32 rx_parity_cfg;
953 	u32 stop_bit_len;
954 	unsigned int clk_div;
955 	u32 ser_clk_cfg;
956 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
957 	unsigned long clk_rate;
958 	u32 ver, sampling_rate;
959 
960 	qcom_geni_serial_stop_rx(uport);
961 	/* baud rate */
962 	baud = uart_get_baud_rate(uport, termios, old, 300, 4000000);
963 	port->baud = baud;
964 
965 	sampling_rate = UART_OVERSAMPLING;
966 	/* Sampling rate is halved for IP versions >= 2.5 */
967 	ver = geni_se_get_qup_hw_version(&port->se);
968 	if (GENI_SE_VERSION_MAJOR(ver) >= 2 && GENI_SE_VERSION_MINOR(ver) >= 5)
969 		sampling_rate /= 2;
970 
971 	clk_rate = get_clk_div_rate(baud, sampling_rate, &clk_div);
972 	if (!clk_rate)
973 		goto out_restart_rx;
974 
975 	uport->uartclk = clk_rate;
976 	clk_set_rate(port->se.clk, clk_rate);
977 	ser_clk_cfg = SER_CLK_EN;
978 	ser_clk_cfg |= clk_div << CLK_DIV_SHFT;
979 
980 	/* parity */
981 	tx_trans_cfg = readl(uport->membase + SE_UART_TX_TRANS_CFG);
982 	tx_parity_cfg = readl(uport->membase + SE_UART_TX_PARITY_CFG);
983 	rx_trans_cfg = readl(uport->membase + SE_UART_RX_TRANS_CFG);
984 	rx_parity_cfg = readl(uport->membase + SE_UART_RX_PARITY_CFG);
985 	if (termios->c_cflag & PARENB) {
986 		tx_trans_cfg |= UART_TX_PAR_EN;
987 		rx_trans_cfg |= UART_RX_PAR_EN;
988 		tx_parity_cfg |= PAR_CALC_EN;
989 		rx_parity_cfg |= PAR_CALC_EN;
990 		if (termios->c_cflag & PARODD) {
991 			tx_parity_cfg |= PAR_ODD;
992 			rx_parity_cfg |= PAR_ODD;
993 		} else if (termios->c_cflag & CMSPAR) {
994 			tx_parity_cfg |= PAR_SPACE;
995 			rx_parity_cfg |= PAR_SPACE;
996 		} else {
997 			tx_parity_cfg |= PAR_EVEN;
998 			rx_parity_cfg |= PAR_EVEN;
999 		}
1000 	} else {
1001 		tx_trans_cfg &= ~UART_TX_PAR_EN;
1002 		rx_trans_cfg &= ~UART_RX_PAR_EN;
1003 		tx_parity_cfg &= ~PAR_CALC_EN;
1004 		rx_parity_cfg &= ~PAR_CALC_EN;
1005 	}
1006 
1007 	/* bits per char */
1008 	switch (termios->c_cflag & CSIZE) {
1009 	case CS5:
1010 		bits_per_char = 5;
1011 		break;
1012 	case CS6:
1013 		bits_per_char = 6;
1014 		break;
1015 	case CS7:
1016 		bits_per_char = 7;
1017 		break;
1018 	case CS8:
1019 	default:
1020 		bits_per_char = 8;
1021 		break;
1022 	}
1023 
1024 	/* stop bits */
1025 	if (termios->c_cflag & CSTOPB)
1026 		stop_bit_len = TX_STOP_BIT_LEN_2;
1027 	else
1028 		stop_bit_len = TX_STOP_BIT_LEN_1;
1029 
1030 	/* flow control, clear the CTS_MASK bit if using flow control. */
1031 	if (termios->c_cflag & CRTSCTS)
1032 		tx_trans_cfg &= ~UART_CTS_MASK;
1033 	else
1034 		tx_trans_cfg |= UART_CTS_MASK;
1035 
1036 	if (baud)
1037 		uart_update_timeout(uport, termios->c_cflag, baud);
1038 
1039 	if (!uart_console(uport))
1040 		writel(port->loopback,
1041 				uport->membase + SE_UART_LOOPBACK_CFG);
1042 	writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1043 	writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1044 	writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1045 	writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1046 	writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1047 	writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1048 	writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1049 	writel(ser_clk_cfg, uport->membase + GENI_SER_M_CLK_CFG);
1050 	writel(ser_clk_cfg, uport->membase + GENI_SER_S_CLK_CFG);
1051 out_restart_rx:
1052 	qcom_geni_serial_start_rx(uport);
1053 }
1054 
1055 static unsigned int qcom_geni_serial_tx_empty(struct uart_port *uport)
1056 {
1057 	return !readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
1058 }
1059 
1060 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
1061 static int __init qcom_geni_console_setup(struct console *co, char *options)
1062 {
1063 	struct uart_port *uport;
1064 	struct qcom_geni_serial_port *port;
1065 	int baud = 9600;
1066 	int bits = 8;
1067 	int parity = 'n';
1068 	int flow = 'n';
1069 	int ret;
1070 
1071 	if (co->index >= GENI_UART_CONS_PORTS  || co->index < 0)
1072 		return -ENXIO;
1073 
1074 	port = get_port_from_line(co->index, true);
1075 	if (IS_ERR(port)) {
1076 		pr_err("Invalid line %d\n", co->index);
1077 		return PTR_ERR(port);
1078 	}
1079 
1080 	uport = &port->uport;
1081 
1082 	if (unlikely(!uport->membase))
1083 		return -ENXIO;
1084 
1085 	if (!port->setup) {
1086 		ret = qcom_geni_serial_port_setup(uport);
1087 		if (ret)
1088 			return ret;
1089 	}
1090 
1091 	if (options)
1092 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1093 
1094 	return uart_set_options(uport, co, baud, parity, bits, flow);
1095 }
1096 
1097 static void qcom_geni_serial_earlycon_write(struct console *con,
1098 					const char *s, unsigned int n)
1099 {
1100 	struct earlycon_device *dev = con->data;
1101 
1102 	__qcom_geni_serial_console_write(&dev->port, s, n);
1103 }
1104 
1105 static int __init qcom_geni_serial_earlycon_setup(struct earlycon_device *dev,
1106 								const char *opt)
1107 {
1108 	struct uart_port *uport = &dev->port;
1109 	u32 tx_trans_cfg;
1110 	u32 tx_parity_cfg = 0;	/* Disable Tx Parity */
1111 	u32 rx_trans_cfg = 0;
1112 	u32 rx_parity_cfg = 0;	/* Disable Rx Parity */
1113 	u32 stop_bit_len = 0;	/* Default stop bit length - 1 bit */
1114 	u32 bits_per_char;
1115 	struct geni_se se;
1116 
1117 	if (!uport->membase)
1118 		return -EINVAL;
1119 
1120 	memset(&se, 0, sizeof(se));
1121 	se.base = uport->membase;
1122 	if (geni_se_read_proto(&se) != GENI_SE_UART)
1123 		return -ENXIO;
1124 	/*
1125 	 * Ignore Flow control.
1126 	 * n = 8.
1127 	 */
1128 	tx_trans_cfg = UART_CTS_MASK;
1129 	bits_per_char = BITS_PER_BYTE;
1130 
1131 	/*
1132 	 * Make an unconditional cancel on the main sequencer to reset
1133 	 * it else we could end up in data loss scenarios.
1134 	 */
1135 	qcom_geni_serial_poll_tx_done(uport);
1136 	qcom_geni_serial_abort_rx(uport);
1137 	geni_se_config_packing(&se, BITS_PER_BYTE, 1, false, true, false);
1138 	geni_se_init(&se, DEF_FIFO_DEPTH_WORDS / 2, DEF_FIFO_DEPTH_WORDS - 2);
1139 	geni_se_select_mode(&se, GENI_SE_FIFO);
1140 
1141 	writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1142 	writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1143 	writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1144 	writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1145 	writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1146 	writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1147 	writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1148 
1149 	dev->con->write = qcom_geni_serial_earlycon_write;
1150 	dev->con->setup = NULL;
1151 	return 0;
1152 }
1153 OF_EARLYCON_DECLARE(qcom_geni, "qcom,geni-debug-uart",
1154 				qcom_geni_serial_earlycon_setup);
1155 
1156 static int __init console_register(struct uart_driver *drv)
1157 {
1158 	return uart_register_driver(drv);
1159 }
1160 
1161 static void console_unregister(struct uart_driver *drv)
1162 {
1163 	uart_unregister_driver(drv);
1164 }
1165 
1166 static struct console cons_ops = {
1167 	.name = "ttyMSM",
1168 	.write = qcom_geni_serial_console_write,
1169 	.device = uart_console_device,
1170 	.setup = qcom_geni_console_setup,
1171 	.flags = CON_PRINTBUFFER,
1172 	.index = -1,
1173 	.data = &qcom_geni_console_driver,
1174 };
1175 
1176 static struct uart_driver qcom_geni_console_driver = {
1177 	.owner = THIS_MODULE,
1178 	.driver_name = "qcom_geni_console",
1179 	.dev_name = "ttyMSM",
1180 	.nr =  GENI_UART_CONS_PORTS,
1181 	.cons = &cons_ops,
1182 };
1183 #else
1184 static int console_register(struct uart_driver *drv)
1185 {
1186 	return 0;
1187 }
1188 
1189 static void console_unregister(struct uart_driver *drv)
1190 {
1191 }
1192 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
1193 
1194 static struct uart_driver qcom_geni_uart_driver = {
1195 	.owner = THIS_MODULE,
1196 	.driver_name = "qcom_geni_uart",
1197 	.dev_name = "ttyHS",
1198 	.nr =  GENI_UART_PORTS,
1199 };
1200 
1201 static void qcom_geni_serial_pm(struct uart_port *uport,
1202 		unsigned int new_state, unsigned int old_state)
1203 {
1204 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
1205 
1206 	/* If we've never been called, treat it as off */
1207 	if (old_state == UART_PM_STATE_UNDEFINED)
1208 		old_state = UART_PM_STATE_OFF;
1209 
1210 	if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF)
1211 		geni_se_resources_on(&port->se);
1212 	else if (new_state == UART_PM_STATE_OFF &&
1213 			old_state == UART_PM_STATE_ON)
1214 		geni_se_resources_off(&port->se);
1215 }
1216 
1217 static const struct uart_ops qcom_geni_console_pops = {
1218 	.tx_empty = qcom_geni_serial_tx_empty,
1219 	.stop_tx = qcom_geni_serial_stop_tx,
1220 	.start_tx = qcom_geni_serial_start_tx,
1221 	.stop_rx = qcom_geni_serial_stop_rx,
1222 	.set_termios = qcom_geni_serial_set_termios,
1223 	.startup = qcom_geni_serial_startup,
1224 	.request_port = qcom_geni_serial_request_port,
1225 	.config_port = qcom_geni_serial_config_port,
1226 	.shutdown = qcom_geni_serial_shutdown,
1227 	.type = qcom_geni_serial_get_type,
1228 	.set_mctrl = qcom_geni_serial_set_mctrl,
1229 	.get_mctrl = qcom_geni_serial_get_mctrl,
1230 #ifdef CONFIG_CONSOLE_POLL
1231 	.poll_get_char	= qcom_geni_serial_get_char,
1232 	.poll_put_char	= qcom_geni_serial_poll_put_char,
1233 #endif
1234 	.pm = qcom_geni_serial_pm,
1235 };
1236 
1237 static const struct uart_ops qcom_geni_uart_pops = {
1238 	.tx_empty = qcom_geni_serial_tx_empty,
1239 	.stop_tx = qcom_geni_serial_stop_tx,
1240 	.start_tx = qcom_geni_serial_start_tx,
1241 	.stop_rx = qcom_geni_serial_stop_rx,
1242 	.set_termios = qcom_geni_serial_set_termios,
1243 	.startup = qcom_geni_serial_startup,
1244 	.request_port = qcom_geni_serial_request_port,
1245 	.config_port = qcom_geni_serial_config_port,
1246 	.shutdown = qcom_geni_serial_shutdown,
1247 	.type = qcom_geni_serial_get_type,
1248 	.set_mctrl = qcom_geni_serial_set_mctrl,
1249 	.get_mctrl = qcom_geni_serial_get_mctrl,
1250 	.pm = qcom_geni_serial_pm,
1251 };
1252 
1253 static int qcom_geni_serial_probe(struct platform_device *pdev)
1254 {
1255 	int ret = 0;
1256 	int line = -1;
1257 	struct qcom_geni_serial_port *port;
1258 	struct uart_port *uport;
1259 	struct resource *res;
1260 	int irq;
1261 	bool console = false;
1262 	struct uart_driver *drv;
1263 
1264 	if (of_device_is_compatible(pdev->dev.of_node, "qcom,geni-debug-uart"))
1265 		console = true;
1266 
1267 	if (console) {
1268 		drv = &qcom_geni_console_driver;
1269 		line = of_alias_get_id(pdev->dev.of_node, "serial");
1270 	} else {
1271 		drv = &qcom_geni_uart_driver;
1272 		line = of_alias_get_id(pdev->dev.of_node, "hsuart");
1273 	}
1274 
1275 	port = get_port_from_line(line, console);
1276 	if (IS_ERR(port)) {
1277 		dev_err(&pdev->dev, "Invalid line %d\n", line);
1278 		return PTR_ERR(port);
1279 	}
1280 
1281 	uport = &port->uport;
1282 	/* Don't allow 2 drivers to access the same port */
1283 	if (uport->private_data)
1284 		return -ENODEV;
1285 
1286 	uport->dev = &pdev->dev;
1287 	port->se.dev = &pdev->dev;
1288 	port->se.wrapper = dev_get_drvdata(pdev->dev.parent);
1289 	port->se.clk = devm_clk_get(&pdev->dev, "se");
1290 	if (IS_ERR(port->se.clk)) {
1291 		ret = PTR_ERR(port->se.clk);
1292 		dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret);
1293 		return ret;
1294 	}
1295 
1296 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1297 	if (!res)
1298 		return -EINVAL;
1299 	uport->mapbase = res->start;
1300 
1301 	port->tx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1302 	port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1303 	port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;
1304 
1305 	scnprintf(port->name, sizeof(port->name), "qcom_geni_serial_%s%d",
1306 		(uart_console(uport) ? "console" : "uart"), uport->line);
1307 	irq = platform_get_irq(pdev, 0);
1308 	if (irq < 0)
1309 		return irq;
1310 	uport->irq = irq;
1311 
1312 	irq_set_status_flags(uport->irq, IRQ_NOAUTOEN);
1313 	ret = devm_request_irq(uport->dev, uport->irq, qcom_geni_serial_isr,
1314 			IRQF_TRIGGER_HIGH, port->name, uport);
1315 	if (ret) {
1316 		dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret);
1317 		return ret;
1318 	}
1319 
1320 	if (!console) {
1321 		port->wakeup_irq = platform_get_irq(pdev, 1);
1322 		if (port->wakeup_irq < 0) {
1323 			dev_err(&pdev->dev, "Failed to get wakeup IRQ %d\n",
1324 					port->wakeup_irq);
1325 		} else {
1326 			irq_set_status_flags(port->wakeup_irq, IRQ_NOAUTOEN);
1327 			ret = devm_request_irq(uport->dev, port->wakeup_irq,
1328 				qcom_geni_serial_wakeup_isr,
1329 				IRQF_TRIGGER_FALLING, "uart_wakeup", uport);
1330 			if (ret) {
1331 				dev_err(uport->dev, "Failed to register wakeup IRQ ret %d\n",
1332 						ret);
1333 				return ret;
1334 			}
1335 
1336 			device_init_wakeup(&pdev->dev, true);
1337 			ret = dev_pm_set_wake_irq(&pdev->dev, port->wakeup_irq);
1338 			if (unlikely(ret))
1339 				dev_err(uport->dev, "%s:Failed to set IRQ wake:%d\n",
1340 						__func__, ret);
1341 		}
1342 	}
1343 	uport->private_data = drv;
1344 	platform_set_drvdata(pdev, port);
1345 	port->handle_rx = console ? handle_rx_console : handle_rx_uart;
1346 	if (!console)
1347 		device_create_file(uport->dev, &dev_attr_loopback);
1348 	return uart_add_one_port(drv, uport);
1349 }
1350 
1351 static int qcom_geni_serial_remove(struct platform_device *pdev)
1352 {
1353 	struct qcom_geni_serial_port *port = platform_get_drvdata(pdev);
1354 	struct uart_driver *drv = port->uport.private_data;
1355 
1356 	uart_remove_one_port(drv, &port->uport);
1357 	return 0;
1358 }
1359 
1360 static int __maybe_unused qcom_geni_serial_sys_suspend(struct device *dev)
1361 {
1362 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1363 	struct uart_port *uport = &port->uport;
1364 
1365 	uart_suspend_port(uport->private_data, uport);
1366 
1367 	if (port->wakeup_irq > 0)
1368 		enable_irq(port->wakeup_irq);
1369 
1370 	return 0;
1371 }
1372 
1373 static int __maybe_unused qcom_geni_serial_sys_resume(struct device *dev)
1374 {
1375 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1376 	struct uart_port *uport = &port->uport;
1377 
1378 	if (port->wakeup_irq > 0)
1379 		disable_irq(port->wakeup_irq);
1380 
1381 	return uart_resume_port(uport->private_data, uport);
1382 }
1383 
1384 static const struct dev_pm_ops qcom_geni_serial_pm_ops = {
1385 	SET_SYSTEM_SLEEP_PM_OPS(qcom_geni_serial_sys_suspend,
1386 					qcom_geni_serial_sys_resume)
1387 };
1388 
1389 static const struct of_device_id qcom_geni_serial_match_table[] = {
1390 	{ .compatible = "qcom,geni-debug-uart", },
1391 	{ .compatible = "qcom,geni-uart", },
1392 	{}
1393 };
1394 MODULE_DEVICE_TABLE(of, qcom_geni_serial_match_table);
1395 
1396 static struct platform_driver qcom_geni_serial_platform_driver = {
1397 	.remove = qcom_geni_serial_remove,
1398 	.probe = qcom_geni_serial_probe,
1399 	.driver = {
1400 		.name = "qcom_geni_serial",
1401 		.of_match_table = qcom_geni_serial_match_table,
1402 		.pm = &qcom_geni_serial_pm_ops,
1403 	},
1404 };
1405 
1406 static int __init qcom_geni_serial_init(void)
1407 {
1408 	int ret;
1409 
1410 	ret = console_register(&qcom_geni_console_driver);
1411 	if (ret)
1412 		return ret;
1413 
1414 	ret = uart_register_driver(&qcom_geni_uart_driver);
1415 	if (ret) {
1416 		console_unregister(&qcom_geni_console_driver);
1417 		return ret;
1418 	}
1419 
1420 	ret = platform_driver_register(&qcom_geni_serial_platform_driver);
1421 	if (ret) {
1422 		console_unregister(&qcom_geni_console_driver);
1423 		uart_unregister_driver(&qcom_geni_uart_driver);
1424 	}
1425 	return ret;
1426 }
1427 module_init(qcom_geni_serial_init);
1428 
1429 static void __exit qcom_geni_serial_exit(void)
1430 {
1431 	platform_driver_unregister(&qcom_geni_serial_platform_driver);
1432 	console_unregister(&qcom_geni_console_driver);
1433 	uart_unregister_driver(&qcom_geni_uart_driver);
1434 }
1435 module_exit(qcom_geni_serial_exit);
1436 
1437 MODULE_DESCRIPTION("Serial driver for GENI based QUP cores");
1438 MODULE_LICENSE("GPL v2");
1439