1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
3 
4 #include <linux/clk.h>
5 #include <linux/console.h>
6 #include <linux/io.h>
7 #include <linux/iopoll.h>
8 #include <linux/irq.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/of_device.h>
12 #include <linux/pm_opp.h>
13 #include <linux/platform_device.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/pm_wakeirq.h>
16 #include <linux/qcom-geni-se.h>
17 #include <linux/serial.h>
18 #include <linux/serial_core.h>
19 #include <linux/slab.h>
20 #include <linux/tty.h>
21 #include <linux/tty_flip.h>
22 
23 /* UART specific GENI registers */
24 #define SE_UART_LOOPBACK_CFG		0x22c
25 #define SE_UART_IO_MACRO_CTRL		0x240
26 #define SE_UART_TX_TRANS_CFG		0x25c
27 #define SE_UART_TX_WORD_LEN		0x268
28 #define SE_UART_TX_STOP_BIT_LEN		0x26c
29 #define SE_UART_TX_TRANS_LEN		0x270
30 #define SE_UART_RX_TRANS_CFG		0x280
31 #define SE_UART_RX_WORD_LEN		0x28c
32 #define SE_UART_RX_STALE_CNT		0x294
33 #define SE_UART_TX_PARITY_CFG		0x2a4
34 #define SE_UART_RX_PARITY_CFG		0x2a8
35 #define SE_UART_MANUAL_RFR		0x2ac
36 
37 /* SE_UART_TRANS_CFG */
38 #define UART_TX_PAR_EN		BIT(0)
39 #define UART_CTS_MASK		BIT(1)
40 
41 /* SE_UART_TX_WORD_LEN */
42 #define TX_WORD_LEN_MSK		GENMASK(9, 0)
43 
44 /* SE_UART_TX_STOP_BIT_LEN */
45 #define TX_STOP_BIT_LEN_MSK	GENMASK(23, 0)
46 #define TX_STOP_BIT_LEN_1	0
47 #define TX_STOP_BIT_LEN_1_5	1
48 #define TX_STOP_BIT_LEN_2	2
49 
50 /* SE_UART_TX_TRANS_LEN */
51 #define TX_TRANS_LEN_MSK	GENMASK(23, 0)
52 
53 /* SE_UART_RX_TRANS_CFG */
54 #define UART_RX_INS_STATUS_BIT	BIT(2)
55 #define UART_RX_PAR_EN		BIT(3)
56 
57 /* SE_UART_RX_WORD_LEN */
58 #define RX_WORD_LEN_MASK	GENMASK(9, 0)
59 
60 /* SE_UART_RX_STALE_CNT */
61 #define RX_STALE_CNT		GENMASK(23, 0)
62 
63 /* SE_UART_TX_PARITY_CFG/RX_PARITY_CFG */
64 #define PAR_CALC_EN		BIT(0)
65 #define PAR_MODE_MSK		GENMASK(2, 1)
66 #define PAR_MODE_SHFT		1
67 #define PAR_EVEN		0x00
68 #define PAR_ODD			0x01
69 #define PAR_SPACE		0x10
70 #define PAR_MARK		0x11
71 
72 /* SE_UART_MANUAL_RFR register fields */
73 #define UART_MANUAL_RFR_EN	BIT(31)
74 #define UART_RFR_NOT_READY	BIT(1)
75 #define UART_RFR_READY		BIT(0)
76 
77 /* UART M_CMD OP codes */
78 #define UART_START_TX		0x1
79 #define UART_START_BREAK	0x4
80 #define UART_STOP_BREAK		0x5
81 /* UART S_CMD OP codes */
82 #define UART_START_READ		0x1
83 #define UART_PARAM		0x1
84 
85 #define UART_OVERSAMPLING	32
86 #define STALE_TIMEOUT		16
87 #define DEFAULT_BITS_PER_CHAR	10
88 #define GENI_UART_CONS_PORTS	1
89 #define GENI_UART_PORTS		3
90 #define DEF_FIFO_DEPTH_WORDS	16
91 #define DEF_TX_WM		2
92 #define DEF_FIFO_WIDTH_BITS	32
93 #define UART_RX_WM		2
94 
95 /* SE_UART_LOOPBACK_CFG */
96 #define RX_TX_SORTED	BIT(0)
97 #define CTS_RTS_SORTED	BIT(1)
98 #define RX_TX_CTS_RTS_SORTED	(RX_TX_SORTED | CTS_RTS_SORTED)
99 
100 /* UART pin swap value */
101 #define DEFAULT_IO_MACRO_IO0_IO1_MASK		GENMASK(3, 0)
102 #define IO_MACRO_IO0_SEL		0x3
103 #define DEFAULT_IO_MACRO_IO2_IO3_MASK		GENMASK(15, 4)
104 #define IO_MACRO_IO2_IO3_SWAP		0x4640
105 
106 /* We always configure 4 bytes per FIFO word */
107 #define BYTES_PER_FIFO_WORD		4
108 
109 struct qcom_geni_private_data {
110 	/* NOTE: earlycon port will have NULL here */
111 	struct uart_driver *drv;
112 
113 	u32 poll_cached_bytes;
114 	unsigned int poll_cached_bytes_cnt;
115 
116 	u32 write_cached_bytes;
117 	unsigned int write_cached_bytes_cnt;
118 };
119 
120 struct qcom_geni_serial_port {
121 	struct uart_port uport;
122 	struct geni_se se;
123 	const char *name;
124 	u32 tx_fifo_depth;
125 	u32 tx_fifo_width;
126 	u32 rx_fifo_depth;
127 	bool setup;
128 	int (*handle_rx)(struct uart_port *uport, u32 bytes, bool drop);
129 	unsigned int baud;
130 	void *rx_fifo;
131 	u32 loopback;
132 	bool brk;
133 
134 	unsigned int tx_remaining;
135 	int wakeup_irq;
136 	bool rx_tx_swap;
137 	bool cts_rts_swap;
138 
139 	struct qcom_geni_private_data private_data;
140 };
141 
142 static const struct uart_ops qcom_geni_console_pops;
143 static const struct uart_ops qcom_geni_uart_pops;
144 static struct uart_driver qcom_geni_console_driver;
145 static struct uart_driver qcom_geni_uart_driver;
146 static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop);
147 static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop);
148 static unsigned int qcom_geni_serial_tx_empty(struct uart_port *port);
149 static void qcom_geni_serial_stop_rx(struct uart_port *uport);
150 static void qcom_geni_serial_handle_rx(struct uart_port *uport, bool drop);
151 
152 #define to_dev_port(ptr, member) \
153 		container_of(ptr, struct qcom_geni_serial_port, member)
154 
155 static struct qcom_geni_serial_port qcom_geni_uart_ports[GENI_UART_PORTS] = {
156 	[0] = {
157 		.uport = {
158 				.iotype = UPIO_MEM,
159 				.ops = &qcom_geni_uart_pops,
160 				.flags = UPF_BOOT_AUTOCONF,
161 				.line = 0,
162 		},
163 	},
164 	[1] = {
165 		.uport = {
166 				.iotype = UPIO_MEM,
167 				.ops = &qcom_geni_uart_pops,
168 				.flags = UPF_BOOT_AUTOCONF,
169 				.line = 1,
170 		},
171 	},
172 	[2] = {
173 		.uport = {
174 				.iotype = UPIO_MEM,
175 				.ops = &qcom_geni_uart_pops,
176 				.flags = UPF_BOOT_AUTOCONF,
177 				.line = 2,
178 		},
179 	},
180 };
181 
182 static struct qcom_geni_serial_port qcom_geni_console_port = {
183 	.uport = {
184 		.iotype = UPIO_MEM,
185 		.ops = &qcom_geni_console_pops,
186 		.flags = UPF_BOOT_AUTOCONF,
187 		.line = 0,
188 	},
189 };
190 
191 static int qcom_geni_serial_request_port(struct uart_port *uport)
192 {
193 	struct platform_device *pdev = to_platform_device(uport->dev);
194 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
195 
196 	uport->membase = devm_platform_ioremap_resource(pdev, 0);
197 	if (IS_ERR(uport->membase))
198 		return PTR_ERR(uport->membase);
199 	port->se.base = uport->membase;
200 	return 0;
201 }
202 
203 static void qcom_geni_serial_config_port(struct uart_port *uport, int cfg_flags)
204 {
205 	if (cfg_flags & UART_CONFIG_TYPE) {
206 		uport->type = PORT_MSM;
207 		qcom_geni_serial_request_port(uport);
208 	}
209 }
210 
211 static unsigned int qcom_geni_serial_get_mctrl(struct uart_port *uport)
212 {
213 	unsigned int mctrl = TIOCM_DSR | TIOCM_CAR;
214 	u32 geni_ios;
215 
216 	if (uart_console(uport)) {
217 		mctrl |= TIOCM_CTS;
218 	} else {
219 		geni_ios = readl(uport->membase + SE_GENI_IOS);
220 		if (!(geni_ios & IO2_DATA_IN))
221 			mctrl |= TIOCM_CTS;
222 	}
223 
224 	return mctrl;
225 }
226 
227 static void qcom_geni_serial_set_mctrl(struct uart_port *uport,
228 							unsigned int mctrl)
229 {
230 	u32 uart_manual_rfr = 0;
231 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
232 
233 	if (uart_console(uport))
234 		return;
235 
236 	if (mctrl & TIOCM_LOOP)
237 		port->loopback = RX_TX_CTS_RTS_SORTED;
238 
239 	if (!(mctrl & TIOCM_RTS) && !uport->suspended)
240 		uart_manual_rfr = UART_MANUAL_RFR_EN | UART_RFR_NOT_READY;
241 	writel(uart_manual_rfr, uport->membase + SE_UART_MANUAL_RFR);
242 }
243 
244 static const char *qcom_geni_serial_get_type(struct uart_port *uport)
245 {
246 	return "MSM";
247 }
248 
249 static struct qcom_geni_serial_port *get_port_from_line(int line, bool console)
250 {
251 	struct qcom_geni_serial_port *port;
252 	int nr_ports = console ? GENI_UART_CONS_PORTS : GENI_UART_PORTS;
253 
254 	if (line < 0 || line >= nr_ports)
255 		return ERR_PTR(-ENXIO);
256 
257 	port = console ? &qcom_geni_console_port : &qcom_geni_uart_ports[line];
258 	return port;
259 }
260 
261 static bool qcom_geni_serial_poll_bit(struct uart_port *uport,
262 				int offset, int field, bool set)
263 {
264 	u32 reg;
265 	struct qcom_geni_serial_port *port;
266 	unsigned int baud;
267 	unsigned int fifo_bits;
268 	unsigned long timeout_us = 20000;
269 	struct qcom_geni_private_data *private_data = uport->private_data;
270 
271 	if (private_data->drv) {
272 		port = to_dev_port(uport, uport);
273 		baud = port->baud;
274 		if (!baud)
275 			baud = 115200;
276 		fifo_bits = port->tx_fifo_depth * port->tx_fifo_width;
277 		/*
278 		 * Total polling iterations based on FIFO worth of bytes to be
279 		 * sent at current baud. Add a little fluff to the wait.
280 		 */
281 		timeout_us = ((fifo_bits * USEC_PER_SEC) / baud) + 500;
282 	}
283 
284 	/*
285 	 * Use custom implementation instead of readl_poll_atomic since ktimer
286 	 * is not ready at the time of early console.
287 	 */
288 	timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10;
289 	while (timeout_us) {
290 		reg = readl(uport->membase + offset);
291 		if ((bool)(reg & field) == set)
292 			return true;
293 		udelay(10);
294 		timeout_us -= 10;
295 	}
296 	return false;
297 }
298 
299 static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size)
300 {
301 	u32 m_cmd;
302 
303 	writel(xmit_size, uport->membase + SE_UART_TX_TRANS_LEN);
304 	m_cmd = UART_START_TX << M_OPCODE_SHFT;
305 	writel(m_cmd, uport->membase + SE_GENI_M_CMD0);
306 }
307 
308 static void qcom_geni_serial_poll_tx_done(struct uart_port *uport)
309 {
310 	int done;
311 	u32 irq_clear = M_CMD_DONE_EN;
312 
313 	done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
314 						M_CMD_DONE_EN, true);
315 	if (!done) {
316 		writel(M_GENI_CMD_ABORT, uport->membase +
317 						SE_GENI_M_CMD_CTRL_REG);
318 		irq_clear |= M_CMD_ABORT_EN;
319 		qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
320 							M_CMD_ABORT_EN, true);
321 	}
322 	writel(irq_clear, uport->membase + SE_GENI_M_IRQ_CLEAR);
323 }
324 
325 static void qcom_geni_serial_abort_rx(struct uart_port *uport)
326 {
327 	u32 irq_clear = S_CMD_DONE_EN | S_CMD_ABORT_EN;
328 
329 	writel(S_GENI_CMD_ABORT, uport->membase + SE_GENI_S_CMD_CTRL_REG);
330 	qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG,
331 					S_GENI_CMD_ABORT, false);
332 	writel(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR);
333 	writel(FORCE_DEFAULT, uport->membase + GENI_FORCE_DEFAULT_REG);
334 }
335 
336 #ifdef CONFIG_CONSOLE_POLL
337 
338 static int qcom_geni_serial_get_char(struct uart_port *uport)
339 {
340 	struct qcom_geni_private_data *private_data = uport->private_data;
341 	u32 status;
342 	u32 word_cnt;
343 	int ret;
344 
345 	if (!private_data->poll_cached_bytes_cnt) {
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 		word_cnt = status & RX_FIFO_WC_MSK;
354 		if (!word_cnt)
355 			return NO_POLL_CHAR;
356 
357 		if (word_cnt == 1 && (status & RX_LAST))
358 			/*
359 			 * NOTE: If RX_LAST_BYTE_VALID is 0 it needs to be
360 			 * treated as if it was BYTES_PER_FIFO_WORD.
361 			 */
362 			private_data->poll_cached_bytes_cnt =
363 				(status & RX_LAST_BYTE_VALID_MSK) >>
364 				RX_LAST_BYTE_VALID_SHFT;
365 
366 		if (private_data->poll_cached_bytes_cnt == 0)
367 			private_data->poll_cached_bytes_cnt = BYTES_PER_FIFO_WORD;
368 
369 		private_data->poll_cached_bytes =
370 			readl(uport->membase + SE_GENI_RX_FIFOn);
371 	}
372 
373 	private_data->poll_cached_bytes_cnt--;
374 	ret = private_data->poll_cached_bytes & 0xff;
375 	private_data->poll_cached_bytes >>= 8;
376 
377 	return ret;
378 }
379 
380 static void qcom_geni_serial_poll_put_char(struct uart_port *uport,
381 							unsigned char c)
382 {
383 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
384 	qcom_geni_serial_setup_tx(uport, 1);
385 	WARN_ON(!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
386 						M_TX_FIFO_WATERMARK_EN, true));
387 	writel(c, uport->membase + SE_GENI_TX_FIFOn);
388 	writel(M_TX_FIFO_WATERMARK_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
389 	qcom_geni_serial_poll_tx_done(uport);
390 }
391 #endif
392 
393 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
394 static void qcom_geni_serial_wr_char(struct uart_port *uport, unsigned char ch)
395 {
396 	struct qcom_geni_private_data *private_data = uport->private_data;
397 
398 	private_data->write_cached_bytes =
399 		(private_data->write_cached_bytes >> 8) | (ch << 24);
400 	private_data->write_cached_bytes_cnt++;
401 
402 	if (private_data->write_cached_bytes_cnt == BYTES_PER_FIFO_WORD) {
403 		writel(private_data->write_cached_bytes,
404 		       uport->membase + SE_GENI_TX_FIFOn);
405 		private_data->write_cached_bytes_cnt = 0;
406 	}
407 }
408 
409 static void
410 __qcom_geni_serial_console_write(struct uart_port *uport, const char *s,
411 				 unsigned int count)
412 {
413 	struct qcom_geni_private_data *private_data = uport->private_data;
414 
415 	int i;
416 	u32 bytes_to_send = count;
417 
418 	for (i = 0; i < count; i++) {
419 		/*
420 		 * uart_console_write() adds a carriage return for each newline.
421 		 * Account for additional bytes to be written.
422 		 */
423 		if (s[i] == '\n')
424 			bytes_to_send++;
425 	}
426 
427 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
428 	qcom_geni_serial_setup_tx(uport, bytes_to_send);
429 	for (i = 0; i < count; ) {
430 		size_t chars_to_write = 0;
431 		size_t avail = DEF_FIFO_DEPTH_WORDS - DEF_TX_WM;
432 
433 		/*
434 		 * If the WM bit never set, then the Tx state machine is not
435 		 * in a valid state, so break, cancel/abort any existing
436 		 * command. Unfortunately the current data being written is
437 		 * lost.
438 		 */
439 		if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
440 						M_TX_FIFO_WATERMARK_EN, true))
441 			break;
442 		chars_to_write = min_t(size_t, count - i, avail / 2);
443 		uart_console_write(uport, s + i, chars_to_write,
444 						qcom_geni_serial_wr_char);
445 		writel(M_TX_FIFO_WATERMARK_EN, uport->membase +
446 							SE_GENI_M_IRQ_CLEAR);
447 		i += chars_to_write;
448 	}
449 
450 	if (private_data->write_cached_bytes_cnt) {
451 		private_data->write_cached_bytes >>= BITS_PER_BYTE *
452 			(BYTES_PER_FIFO_WORD - private_data->write_cached_bytes_cnt);
453 		writel(private_data->write_cached_bytes,
454 		       uport->membase + SE_GENI_TX_FIFOn);
455 		private_data->write_cached_bytes_cnt = 0;
456 	}
457 
458 	qcom_geni_serial_poll_tx_done(uport);
459 }
460 
461 static void qcom_geni_serial_console_write(struct console *co, const char *s,
462 			      unsigned int count)
463 {
464 	struct uart_port *uport;
465 	struct qcom_geni_serial_port *port;
466 	bool locked = true;
467 	unsigned long flags;
468 	u32 geni_status;
469 	u32 irq_en;
470 
471 	WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS);
472 
473 	port = get_port_from_line(co->index, true);
474 	if (IS_ERR(port))
475 		return;
476 
477 	uport = &port->uport;
478 	if (oops_in_progress)
479 		locked = spin_trylock_irqsave(&uport->lock, flags);
480 	else
481 		spin_lock_irqsave(&uport->lock, flags);
482 
483 	geni_status = readl(uport->membase + SE_GENI_STATUS);
484 
485 	/* Cancel the current write to log the fault */
486 	if (!locked) {
487 		geni_se_cancel_m_cmd(&port->se);
488 		if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
489 						M_CMD_CANCEL_EN, true)) {
490 			geni_se_abort_m_cmd(&port->se);
491 			qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
492 							M_CMD_ABORT_EN, true);
493 			writel(M_CMD_ABORT_EN, uport->membase +
494 							SE_GENI_M_IRQ_CLEAR);
495 		}
496 		writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
497 	} else if ((geni_status & M_GENI_CMD_ACTIVE) && !port->tx_remaining) {
498 		/*
499 		 * It seems we can't interrupt existing transfers if all data
500 		 * has been sent, in which case we need to look for done first.
501 		 */
502 		qcom_geni_serial_poll_tx_done(uport);
503 
504 		if (!uart_circ_empty(&uport->state->xmit)) {
505 			irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
506 			writel(irq_en | M_TX_FIFO_WATERMARK_EN,
507 					uport->membase + SE_GENI_M_IRQ_EN);
508 		}
509 	}
510 
511 	__qcom_geni_serial_console_write(uport, s, count);
512 
513 	if (port->tx_remaining)
514 		qcom_geni_serial_setup_tx(uport, port->tx_remaining);
515 
516 	if (locked)
517 		spin_unlock_irqrestore(&uport->lock, flags);
518 }
519 
520 static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
521 {
522 	u32 i;
523 	unsigned char buf[sizeof(u32)];
524 	struct tty_port *tport;
525 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
526 
527 	tport = &uport->state->port;
528 	for (i = 0; i < bytes; ) {
529 		int c;
530 		int chunk = min_t(int, bytes - i, BYTES_PER_FIFO_WORD);
531 
532 		ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1);
533 		i += chunk;
534 		if (drop)
535 			continue;
536 
537 		for (c = 0; c < chunk; c++) {
538 			int sysrq;
539 
540 			uport->icount.rx++;
541 			if (port->brk && buf[c] == 0) {
542 				port->brk = false;
543 				if (uart_handle_break(uport))
544 					continue;
545 			}
546 
547 			sysrq = uart_prepare_sysrq_char(uport, buf[c]);
548 
549 			if (!sysrq)
550 				tty_insert_flip_char(tport, buf[c], TTY_NORMAL);
551 		}
552 	}
553 	if (!drop)
554 		tty_flip_buffer_push(tport);
555 	return 0;
556 }
557 #else
558 static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
559 {
560 	return -EPERM;
561 }
562 
563 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
564 
565 static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop)
566 {
567 	struct tty_port *tport;
568 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
569 	u32 num_bytes_pw = port->tx_fifo_width / BITS_PER_BYTE;
570 	u32 words = ALIGN(bytes, num_bytes_pw) / num_bytes_pw;
571 	int ret;
572 
573 	tport = &uport->state->port;
574 	ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, port->rx_fifo, words);
575 	if (drop)
576 		return 0;
577 
578 	ret = tty_insert_flip_string(tport, port->rx_fifo, bytes);
579 	if (ret != bytes) {
580 		dev_err(uport->dev, "%s:Unable to push data ret %d_bytes %d\n",
581 				__func__, ret, bytes);
582 		WARN_ON_ONCE(1);
583 	}
584 	uport->icount.rx += ret;
585 	tty_flip_buffer_push(tport);
586 	return ret;
587 }
588 
589 static void qcom_geni_serial_start_tx(struct uart_port *uport)
590 {
591 	u32 irq_en;
592 	u32 status;
593 
594 	status = readl(uport->membase + SE_GENI_STATUS);
595 	if (status & M_GENI_CMD_ACTIVE)
596 		return;
597 
598 	if (!qcom_geni_serial_tx_empty(uport))
599 		return;
600 
601 	irq_en = readl(uport->membase +	SE_GENI_M_IRQ_EN);
602 	irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
603 
604 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
605 	writel(irq_en, uport->membase +	SE_GENI_M_IRQ_EN);
606 }
607 
608 static void qcom_geni_serial_stop_tx(struct uart_port *uport)
609 {
610 	u32 irq_en;
611 	u32 status;
612 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
613 
614 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
615 	irq_en &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
616 	writel(0, uport->membase + SE_GENI_TX_WATERMARK_REG);
617 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
618 	status = readl(uport->membase + SE_GENI_STATUS);
619 	/* Possible stop tx is called multiple times. */
620 	if (!(status & M_GENI_CMD_ACTIVE))
621 		return;
622 
623 	geni_se_cancel_m_cmd(&port->se);
624 	if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
625 						M_CMD_CANCEL_EN, true)) {
626 		geni_se_abort_m_cmd(&port->se);
627 		qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
628 						M_CMD_ABORT_EN, true);
629 		writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
630 	}
631 	writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
632 }
633 
634 static void qcom_geni_serial_start_rx(struct uart_port *uport)
635 {
636 	u32 irq_en;
637 	u32 status;
638 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
639 
640 	status = readl(uport->membase + SE_GENI_STATUS);
641 	if (status & S_GENI_CMD_ACTIVE)
642 		qcom_geni_serial_stop_rx(uport);
643 
644 	geni_se_setup_s_cmd(&port->se, UART_START_READ, 0);
645 
646 	irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
647 	irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN;
648 	writel(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
649 
650 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
651 	irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
652 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
653 }
654 
655 static void qcom_geni_serial_stop_rx(struct uart_port *uport)
656 {
657 	u32 irq_en;
658 	u32 status;
659 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
660 	u32 s_irq_status;
661 
662 	irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
663 	irq_en &= ~(S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN);
664 	writel(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
665 
666 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
667 	irq_en &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
668 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
669 
670 	status = readl(uport->membase + SE_GENI_STATUS);
671 	/* Possible stop rx is called multiple times. */
672 	if (!(status & S_GENI_CMD_ACTIVE))
673 		return;
674 
675 	geni_se_cancel_s_cmd(&port->se);
676 	qcom_geni_serial_poll_bit(uport, SE_GENI_S_IRQ_STATUS,
677 					S_CMD_CANCEL_EN, true);
678 	/*
679 	 * If timeout occurs secondary engine remains active
680 	 * and Abort sequence is executed.
681 	 */
682 	s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
683 	/* Flush the Rx buffer */
684 	if (s_irq_status & S_RX_FIFO_LAST_EN)
685 		qcom_geni_serial_handle_rx(uport, true);
686 	writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
687 
688 	status = readl(uport->membase + SE_GENI_STATUS);
689 	if (status & S_GENI_CMD_ACTIVE)
690 		qcom_geni_serial_abort_rx(uport);
691 }
692 
693 static void qcom_geni_serial_handle_rx(struct uart_port *uport, bool drop)
694 {
695 	u32 status;
696 	u32 word_cnt;
697 	u32 last_word_byte_cnt;
698 	u32 last_word_partial;
699 	u32 total_bytes;
700 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
701 
702 	status = readl(uport->membase +	SE_GENI_RX_FIFO_STATUS);
703 	word_cnt = status & RX_FIFO_WC_MSK;
704 	last_word_partial = status & RX_LAST;
705 	last_word_byte_cnt = (status & RX_LAST_BYTE_VALID_MSK) >>
706 						RX_LAST_BYTE_VALID_SHFT;
707 
708 	if (!word_cnt)
709 		return;
710 	total_bytes = BYTES_PER_FIFO_WORD * (word_cnt - 1);
711 	if (last_word_partial && last_word_byte_cnt)
712 		total_bytes += last_word_byte_cnt;
713 	else
714 		total_bytes += BYTES_PER_FIFO_WORD;
715 	port->handle_rx(uport, total_bytes, drop);
716 }
717 
718 static void qcom_geni_serial_handle_tx(struct uart_port *uport, bool done,
719 		bool active)
720 {
721 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
722 	struct circ_buf *xmit = &uport->state->xmit;
723 	size_t avail;
724 	size_t remaining;
725 	size_t pending;
726 	int i;
727 	u32 status;
728 	u32 irq_en;
729 	unsigned int chunk;
730 	int tail;
731 
732 	status = readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
733 
734 	/* Complete the current tx command before taking newly added data */
735 	if (active)
736 		pending = port->tx_remaining;
737 	else
738 		pending = uart_circ_chars_pending(xmit);
739 
740 	/* All data has been transmitted and acknowledged as received */
741 	if (!pending && !status && done) {
742 		qcom_geni_serial_stop_tx(uport);
743 		goto out_write_wakeup;
744 	}
745 
746 	avail = port->tx_fifo_depth - (status & TX_FIFO_WC);
747 	avail *= BYTES_PER_FIFO_WORD;
748 
749 	tail = xmit->tail;
750 	chunk = min(avail, pending);
751 	if (!chunk)
752 		goto out_write_wakeup;
753 
754 	if (!port->tx_remaining) {
755 		qcom_geni_serial_setup_tx(uport, pending);
756 		port->tx_remaining = pending;
757 
758 		irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
759 		if (!(irq_en & M_TX_FIFO_WATERMARK_EN))
760 			writel(irq_en | M_TX_FIFO_WATERMARK_EN,
761 					uport->membase + SE_GENI_M_IRQ_EN);
762 	}
763 
764 	remaining = chunk;
765 	for (i = 0; i < chunk; ) {
766 		unsigned int tx_bytes;
767 		u8 buf[sizeof(u32)];
768 		int c;
769 
770 		memset(buf, 0, sizeof(buf));
771 		tx_bytes = min_t(size_t, remaining, BYTES_PER_FIFO_WORD);
772 
773 		for (c = 0; c < tx_bytes ; c++) {
774 			buf[c] = xmit->buf[tail++];
775 			tail &= UART_XMIT_SIZE - 1;
776 		}
777 
778 		iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
779 
780 		i += tx_bytes;
781 		uport->icount.tx += tx_bytes;
782 		remaining -= tx_bytes;
783 		port->tx_remaining -= tx_bytes;
784 	}
785 
786 	xmit->tail = tail;
787 
788 	/*
789 	 * The tx fifo watermark is level triggered and latched. Though we had
790 	 * cleared it in qcom_geni_serial_isr it will have already reasserted
791 	 * so we must clear it again here after our writes.
792 	 */
793 	writel(M_TX_FIFO_WATERMARK_EN,
794 			uport->membase + SE_GENI_M_IRQ_CLEAR);
795 
796 out_write_wakeup:
797 	if (!port->tx_remaining) {
798 		irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
799 		if (irq_en & M_TX_FIFO_WATERMARK_EN)
800 			writel(irq_en & ~M_TX_FIFO_WATERMARK_EN,
801 					uport->membase + SE_GENI_M_IRQ_EN);
802 	}
803 
804 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
805 		uart_write_wakeup(uport);
806 }
807 
808 static irqreturn_t qcom_geni_serial_isr(int isr, void *dev)
809 {
810 	u32 m_irq_en;
811 	u32 m_irq_status;
812 	u32 s_irq_status;
813 	u32 geni_status;
814 	struct uart_port *uport = dev;
815 	bool drop_rx = false;
816 	struct tty_port *tport = &uport->state->port;
817 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
818 
819 	if (uport->suspended)
820 		return IRQ_NONE;
821 
822 	spin_lock(&uport->lock);
823 
824 	m_irq_status = readl(uport->membase + SE_GENI_M_IRQ_STATUS);
825 	s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
826 	geni_status = readl(uport->membase + SE_GENI_STATUS);
827 	m_irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
828 	writel(m_irq_status, uport->membase + SE_GENI_M_IRQ_CLEAR);
829 	writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
830 
831 	if (WARN_ON(m_irq_status & M_ILLEGAL_CMD_EN))
832 		goto out_unlock;
833 
834 	if (s_irq_status & S_RX_FIFO_WR_ERR_EN) {
835 		uport->icount.overrun++;
836 		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
837 	}
838 
839 	if (m_irq_status & m_irq_en & (M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN))
840 		qcom_geni_serial_handle_tx(uport, m_irq_status & M_CMD_DONE_EN,
841 					geni_status & M_GENI_CMD_ACTIVE);
842 
843 	if (s_irq_status & S_GP_IRQ_0_EN || s_irq_status & S_GP_IRQ_1_EN) {
844 		if (s_irq_status & S_GP_IRQ_0_EN)
845 			uport->icount.parity++;
846 		drop_rx = true;
847 	} else if (s_irq_status & S_GP_IRQ_2_EN ||
848 					s_irq_status & S_GP_IRQ_3_EN) {
849 		uport->icount.brk++;
850 		port->brk = true;
851 	}
852 
853 	if (s_irq_status & S_RX_FIFO_WATERMARK_EN ||
854 					s_irq_status & S_RX_FIFO_LAST_EN)
855 		qcom_geni_serial_handle_rx(uport, drop_rx);
856 
857 out_unlock:
858 	uart_unlock_and_check_sysrq(uport);
859 
860 	return IRQ_HANDLED;
861 }
862 
863 static void get_tx_fifo_size(struct qcom_geni_serial_port *port)
864 {
865 	struct uart_port *uport;
866 
867 	uport = &port->uport;
868 	port->tx_fifo_depth = geni_se_get_tx_fifo_depth(&port->se);
869 	port->tx_fifo_width = geni_se_get_tx_fifo_width(&port->se);
870 	port->rx_fifo_depth = geni_se_get_rx_fifo_depth(&port->se);
871 	uport->fifosize =
872 		(port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE;
873 }
874 
875 
876 static void qcom_geni_serial_shutdown(struct uart_port *uport)
877 {
878 	disable_irq(uport->irq);
879 }
880 
881 static int qcom_geni_serial_port_setup(struct uart_port *uport)
882 {
883 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
884 	u32 rxstale = DEFAULT_BITS_PER_CHAR * STALE_TIMEOUT;
885 	u32 proto;
886 	u32 pin_swap;
887 
888 	proto = geni_se_read_proto(&port->se);
889 	if (proto != GENI_SE_UART) {
890 		dev_err(uport->dev, "Invalid FW loaded, proto: %d\n", proto);
891 		return -ENXIO;
892 	}
893 
894 	qcom_geni_serial_stop_rx(uport);
895 
896 	get_tx_fifo_size(port);
897 
898 	writel(rxstale, uport->membase + SE_UART_RX_STALE_CNT);
899 
900 	pin_swap = readl(uport->membase + SE_UART_IO_MACRO_CTRL);
901 	if (port->rx_tx_swap) {
902 		pin_swap &= ~DEFAULT_IO_MACRO_IO2_IO3_MASK;
903 		pin_swap |= IO_MACRO_IO2_IO3_SWAP;
904 	}
905 	if (port->cts_rts_swap) {
906 		pin_swap &= ~DEFAULT_IO_MACRO_IO0_IO1_MASK;
907 		pin_swap |= IO_MACRO_IO0_SEL;
908 	}
909 	/* Configure this register if RX-TX, CTS-RTS pins are swapped */
910 	if (port->rx_tx_swap || port->cts_rts_swap)
911 		writel(pin_swap, uport->membase + SE_UART_IO_MACRO_CTRL);
912 
913 	/*
914 	 * Make an unconditional cancel on the main sequencer to reset
915 	 * it else we could end up in data loss scenarios.
916 	 */
917 	if (uart_console(uport))
918 		qcom_geni_serial_poll_tx_done(uport);
919 	geni_se_config_packing(&port->se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
920 			       false, true, true);
921 	geni_se_init(&port->se, UART_RX_WM, port->rx_fifo_depth - 2);
922 	geni_se_select_mode(&port->se, GENI_SE_FIFO);
923 	port->setup = true;
924 
925 	return 0;
926 }
927 
928 static int qcom_geni_serial_startup(struct uart_port *uport)
929 {
930 	int ret;
931 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
932 
933 	if (!port->setup) {
934 		ret = qcom_geni_serial_port_setup(uport);
935 		if (ret)
936 			return ret;
937 	}
938 	enable_irq(uport->irq);
939 
940 	return 0;
941 }
942 
943 static unsigned long get_clk_div_rate(struct clk *clk, unsigned int baud,
944 			unsigned int sampling_rate, unsigned int *clk_div)
945 {
946 	unsigned long ser_clk;
947 	unsigned long desired_clk;
948 	unsigned long freq, prev;
949 	unsigned long div, maxdiv;
950 	int64_t mult;
951 
952 	desired_clk = baud * sampling_rate;
953 	if (!desired_clk) {
954 		pr_err("%s: Invalid frequency\n", __func__);
955 		return 0;
956 	}
957 
958 	maxdiv = CLK_DIV_MSK >> CLK_DIV_SHFT;
959 	prev = 0;
960 
961 	for (div = 1; div <= maxdiv; div++) {
962 		mult = div * desired_clk;
963 		if (mult > ULONG_MAX)
964 			break;
965 
966 		freq = clk_round_rate(clk, (unsigned long)mult);
967 		if (!(freq % desired_clk)) {
968 			ser_clk = freq;
969 			break;
970 		}
971 
972 		if (!prev)
973 			ser_clk = freq;
974 		else if (prev == freq)
975 			break;
976 
977 		prev = freq;
978 	}
979 
980 	if (!ser_clk) {
981 		pr_err("%s: Can't find matching DFS entry for baud %d\n",
982 								__func__, baud);
983 		return ser_clk;
984 	}
985 
986 	*clk_div = ser_clk / desired_clk;
987 	if (!(*clk_div))
988 		*clk_div = 1;
989 
990 	return ser_clk;
991 }
992 
993 static void qcom_geni_serial_set_termios(struct uart_port *uport,
994 				struct ktermios *termios, struct ktermios *old)
995 {
996 	unsigned int baud;
997 	u32 bits_per_char;
998 	u32 tx_trans_cfg;
999 	u32 tx_parity_cfg;
1000 	u32 rx_trans_cfg;
1001 	u32 rx_parity_cfg;
1002 	u32 stop_bit_len;
1003 	unsigned int clk_div;
1004 	u32 ser_clk_cfg;
1005 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
1006 	unsigned long clk_rate;
1007 	u32 ver, sampling_rate;
1008 	unsigned int avg_bw_core;
1009 
1010 	qcom_geni_serial_stop_rx(uport);
1011 	/* baud rate */
1012 	baud = uart_get_baud_rate(uport, termios, old, 300, 4000000);
1013 	port->baud = baud;
1014 
1015 	sampling_rate = UART_OVERSAMPLING;
1016 	/* Sampling rate is halved for IP versions >= 2.5 */
1017 	ver = geni_se_get_qup_hw_version(&port->se);
1018 	if (ver >= QUP_SE_VERSION_2_5)
1019 		sampling_rate /= 2;
1020 
1021 	clk_rate = get_clk_div_rate(port->se.clk, baud,
1022 		sampling_rate, &clk_div);
1023 	if (!clk_rate)
1024 		goto out_restart_rx;
1025 
1026 	uport->uartclk = clk_rate;
1027 	dev_pm_opp_set_rate(uport->dev, clk_rate);
1028 	ser_clk_cfg = SER_CLK_EN;
1029 	ser_clk_cfg |= clk_div << CLK_DIV_SHFT;
1030 
1031 	/*
1032 	 * Bump up BW vote on CPU and CORE path as driver supports FIFO mode
1033 	 * only.
1034 	 */
1035 	avg_bw_core = (baud > 115200) ? Bps_to_icc(CORE_2X_50_MHZ)
1036 						: GENI_DEFAULT_BW;
1037 	port->se.icc_paths[GENI_TO_CORE].avg_bw = avg_bw_core;
1038 	port->se.icc_paths[CPU_TO_GENI].avg_bw = Bps_to_icc(baud);
1039 	geni_icc_set_bw(&port->se);
1040 
1041 	/* parity */
1042 	tx_trans_cfg = readl(uport->membase + SE_UART_TX_TRANS_CFG);
1043 	tx_parity_cfg = readl(uport->membase + SE_UART_TX_PARITY_CFG);
1044 	rx_trans_cfg = readl(uport->membase + SE_UART_RX_TRANS_CFG);
1045 	rx_parity_cfg = readl(uport->membase + SE_UART_RX_PARITY_CFG);
1046 	if (termios->c_cflag & PARENB) {
1047 		tx_trans_cfg |= UART_TX_PAR_EN;
1048 		rx_trans_cfg |= UART_RX_PAR_EN;
1049 		tx_parity_cfg |= PAR_CALC_EN;
1050 		rx_parity_cfg |= PAR_CALC_EN;
1051 		if (termios->c_cflag & PARODD) {
1052 			tx_parity_cfg |= PAR_ODD;
1053 			rx_parity_cfg |= PAR_ODD;
1054 		} else if (termios->c_cflag & CMSPAR) {
1055 			tx_parity_cfg |= PAR_SPACE;
1056 			rx_parity_cfg |= PAR_SPACE;
1057 		} else {
1058 			tx_parity_cfg |= PAR_EVEN;
1059 			rx_parity_cfg |= PAR_EVEN;
1060 		}
1061 	} else {
1062 		tx_trans_cfg &= ~UART_TX_PAR_EN;
1063 		rx_trans_cfg &= ~UART_RX_PAR_EN;
1064 		tx_parity_cfg &= ~PAR_CALC_EN;
1065 		rx_parity_cfg &= ~PAR_CALC_EN;
1066 	}
1067 
1068 	/* bits per char */
1069 	bits_per_char = tty_get_char_size(termios->c_cflag);
1070 
1071 	/* stop bits */
1072 	if (termios->c_cflag & CSTOPB)
1073 		stop_bit_len = TX_STOP_BIT_LEN_2;
1074 	else
1075 		stop_bit_len = TX_STOP_BIT_LEN_1;
1076 
1077 	/* flow control, clear the CTS_MASK bit if using flow control. */
1078 	if (termios->c_cflag & CRTSCTS)
1079 		tx_trans_cfg &= ~UART_CTS_MASK;
1080 	else
1081 		tx_trans_cfg |= UART_CTS_MASK;
1082 
1083 	if (baud)
1084 		uart_update_timeout(uport, termios->c_cflag, baud);
1085 
1086 	if (!uart_console(uport))
1087 		writel(port->loopback,
1088 				uport->membase + SE_UART_LOOPBACK_CFG);
1089 	writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1090 	writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1091 	writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1092 	writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1093 	writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1094 	writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1095 	writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1096 	writel(ser_clk_cfg, uport->membase + GENI_SER_M_CLK_CFG);
1097 	writel(ser_clk_cfg, uport->membase + GENI_SER_S_CLK_CFG);
1098 out_restart_rx:
1099 	qcom_geni_serial_start_rx(uport);
1100 }
1101 
1102 static unsigned int qcom_geni_serial_tx_empty(struct uart_port *uport)
1103 {
1104 	return !readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
1105 }
1106 
1107 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
1108 static int qcom_geni_console_setup(struct console *co, char *options)
1109 {
1110 	struct uart_port *uport;
1111 	struct qcom_geni_serial_port *port;
1112 	int baud = 115200;
1113 	int bits = 8;
1114 	int parity = 'n';
1115 	int flow = 'n';
1116 	int ret;
1117 
1118 	if (co->index >= GENI_UART_CONS_PORTS  || co->index < 0)
1119 		return -ENXIO;
1120 
1121 	port = get_port_from_line(co->index, true);
1122 	if (IS_ERR(port)) {
1123 		pr_err("Invalid line %d\n", co->index);
1124 		return PTR_ERR(port);
1125 	}
1126 
1127 	uport = &port->uport;
1128 
1129 	if (unlikely(!uport->membase))
1130 		return -ENXIO;
1131 
1132 	if (!port->setup) {
1133 		ret = qcom_geni_serial_port_setup(uport);
1134 		if (ret)
1135 			return ret;
1136 	}
1137 
1138 	if (options)
1139 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1140 
1141 	return uart_set_options(uport, co, baud, parity, bits, flow);
1142 }
1143 
1144 static void qcom_geni_serial_earlycon_write(struct console *con,
1145 					const char *s, unsigned int n)
1146 {
1147 	struct earlycon_device *dev = con->data;
1148 
1149 	__qcom_geni_serial_console_write(&dev->port, s, n);
1150 }
1151 
1152 #ifdef CONFIG_CONSOLE_POLL
1153 static int qcom_geni_serial_earlycon_read(struct console *con,
1154 					  char *s, unsigned int n)
1155 {
1156 	struct earlycon_device *dev = con->data;
1157 	struct uart_port *uport = &dev->port;
1158 	int num_read = 0;
1159 	int ch;
1160 
1161 	while (num_read < n) {
1162 		ch = qcom_geni_serial_get_char(uport);
1163 		if (ch == NO_POLL_CHAR)
1164 			break;
1165 		s[num_read++] = ch;
1166 	}
1167 
1168 	return num_read;
1169 }
1170 
1171 static void __init qcom_geni_serial_enable_early_read(struct geni_se *se,
1172 						      struct console *con)
1173 {
1174 	geni_se_setup_s_cmd(se, UART_START_READ, 0);
1175 	con->read = qcom_geni_serial_earlycon_read;
1176 }
1177 #else
1178 static inline void qcom_geni_serial_enable_early_read(struct geni_se *se,
1179 						      struct console *con) { }
1180 #endif
1181 
1182 static struct qcom_geni_private_data earlycon_private_data;
1183 
1184 static int __init qcom_geni_serial_earlycon_setup(struct earlycon_device *dev,
1185 								const char *opt)
1186 {
1187 	struct uart_port *uport = &dev->port;
1188 	u32 tx_trans_cfg;
1189 	u32 tx_parity_cfg = 0;	/* Disable Tx Parity */
1190 	u32 rx_trans_cfg = 0;
1191 	u32 rx_parity_cfg = 0;	/* Disable Rx Parity */
1192 	u32 stop_bit_len = 0;	/* Default stop bit length - 1 bit */
1193 	u32 bits_per_char;
1194 	struct geni_se se;
1195 
1196 	if (!uport->membase)
1197 		return -EINVAL;
1198 
1199 	uport->private_data = &earlycon_private_data;
1200 
1201 	memset(&se, 0, sizeof(se));
1202 	se.base = uport->membase;
1203 	if (geni_se_read_proto(&se) != GENI_SE_UART)
1204 		return -ENXIO;
1205 	/*
1206 	 * Ignore Flow control.
1207 	 * n = 8.
1208 	 */
1209 	tx_trans_cfg = UART_CTS_MASK;
1210 	bits_per_char = BITS_PER_BYTE;
1211 
1212 	/*
1213 	 * Make an unconditional cancel on the main sequencer to reset
1214 	 * it else we could end up in data loss scenarios.
1215 	 */
1216 	qcom_geni_serial_poll_tx_done(uport);
1217 	qcom_geni_serial_abort_rx(uport);
1218 	geni_se_config_packing(&se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
1219 			       false, true, true);
1220 	geni_se_init(&se, DEF_FIFO_DEPTH_WORDS / 2, DEF_FIFO_DEPTH_WORDS - 2);
1221 	geni_se_select_mode(&se, GENI_SE_FIFO);
1222 
1223 	writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1224 	writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1225 	writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1226 	writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1227 	writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1228 	writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1229 	writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1230 
1231 	dev->con->write = qcom_geni_serial_earlycon_write;
1232 	dev->con->setup = NULL;
1233 	qcom_geni_serial_enable_early_read(&se, dev->con);
1234 
1235 	return 0;
1236 }
1237 OF_EARLYCON_DECLARE(qcom_geni, "qcom,geni-debug-uart",
1238 				qcom_geni_serial_earlycon_setup);
1239 
1240 static int __init console_register(struct uart_driver *drv)
1241 {
1242 	return uart_register_driver(drv);
1243 }
1244 
1245 static void console_unregister(struct uart_driver *drv)
1246 {
1247 	uart_unregister_driver(drv);
1248 }
1249 
1250 static struct console cons_ops = {
1251 	.name = "ttyMSM",
1252 	.write = qcom_geni_serial_console_write,
1253 	.device = uart_console_device,
1254 	.setup = qcom_geni_console_setup,
1255 	.flags = CON_PRINTBUFFER,
1256 	.index = -1,
1257 	.data = &qcom_geni_console_driver,
1258 };
1259 
1260 static struct uart_driver qcom_geni_console_driver = {
1261 	.owner = THIS_MODULE,
1262 	.driver_name = "qcom_geni_console",
1263 	.dev_name = "ttyMSM",
1264 	.nr =  GENI_UART_CONS_PORTS,
1265 	.cons = &cons_ops,
1266 };
1267 #else
1268 static int console_register(struct uart_driver *drv)
1269 {
1270 	return 0;
1271 }
1272 
1273 static void console_unregister(struct uart_driver *drv)
1274 {
1275 }
1276 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
1277 
1278 static struct uart_driver qcom_geni_uart_driver = {
1279 	.owner = THIS_MODULE,
1280 	.driver_name = "qcom_geni_uart",
1281 	.dev_name = "ttyHS",
1282 	.nr =  GENI_UART_PORTS,
1283 };
1284 
1285 static void qcom_geni_serial_pm(struct uart_port *uport,
1286 		unsigned int new_state, unsigned int old_state)
1287 {
1288 	struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
1289 
1290 	/* If we've never been called, treat it as off */
1291 	if (old_state == UART_PM_STATE_UNDEFINED)
1292 		old_state = UART_PM_STATE_OFF;
1293 
1294 	if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) {
1295 		geni_icc_enable(&port->se);
1296 		geni_se_resources_on(&port->se);
1297 	} else if (new_state == UART_PM_STATE_OFF &&
1298 			old_state == UART_PM_STATE_ON) {
1299 		geni_se_resources_off(&port->se);
1300 		geni_icc_disable(&port->se);
1301 	}
1302 }
1303 
1304 static const struct uart_ops qcom_geni_console_pops = {
1305 	.tx_empty = qcom_geni_serial_tx_empty,
1306 	.stop_tx = qcom_geni_serial_stop_tx,
1307 	.start_tx = qcom_geni_serial_start_tx,
1308 	.stop_rx = qcom_geni_serial_stop_rx,
1309 	.start_rx = qcom_geni_serial_start_rx,
1310 	.set_termios = qcom_geni_serial_set_termios,
1311 	.startup = qcom_geni_serial_startup,
1312 	.request_port = qcom_geni_serial_request_port,
1313 	.config_port = qcom_geni_serial_config_port,
1314 	.shutdown = qcom_geni_serial_shutdown,
1315 	.type = qcom_geni_serial_get_type,
1316 	.set_mctrl = qcom_geni_serial_set_mctrl,
1317 	.get_mctrl = qcom_geni_serial_get_mctrl,
1318 #ifdef CONFIG_CONSOLE_POLL
1319 	.poll_get_char	= qcom_geni_serial_get_char,
1320 	.poll_put_char	= qcom_geni_serial_poll_put_char,
1321 #endif
1322 	.pm = qcom_geni_serial_pm,
1323 };
1324 
1325 static const struct uart_ops qcom_geni_uart_pops = {
1326 	.tx_empty = qcom_geni_serial_tx_empty,
1327 	.stop_tx = qcom_geni_serial_stop_tx,
1328 	.start_tx = qcom_geni_serial_start_tx,
1329 	.stop_rx = qcom_geni_serial_stop_rx,
1330 	.set_termios = qcom_geni_serial_set_termios,
1331 	.startup = qcom_geni_serial_startup,
1332 	.request_port = qcom_geni_serial_request_port,
1333 	.config_port = qcom_geni_serial_config_port,
1334 	.shutdown = qcom_geni_serial_shutdown,
1335 	.type = qcom_geni_serial_get_type,
1336 	.set_mctrl = qcom_geni_serial_set_mctrl,
1337 	.get_mctrl = qcom_geni_serial_get_mctrl,
1338 	.pm = qcom_geni_serial_pm,
1339 };
1340 
1341 static int qcom_geni_serial_probe(struct platform_device *pdev)
1342 {
1343 	int ret = 0;
1344 	int line;
1345 	struct qcom_geni_serial_port *port;
1346 	struct uart_port *uport;
1347 	struct resource *res;
1348 	int irq;
1349 	bool console = false;
1350 	struct uart_driver *drv;
1351 
1352 	if (of_device_is_compatible(pdev->dev.of_node, "qcom,geni-debug-uart"))
1353 		console = true;
1354 
1355 	if (console) {
1356 		drv = &qcom_geni_console_driver;
1357 		line = of_alias_get_id(pdev->dev.of_node, "serial");
1358 	} else {
1359 		drv = &qcom_geni_uart_driver;
1360 		line = of_alias_get_id(pdev->dev.of_node, "serial");
1361 		if (line == -ENODEV) /* compat with non-standard aliases */
1362 			line = of_alias_get_id(pdev->dev.of_node, "hsuart");
1363 	}
1364 
1365 	port = get_port_from_line(line, console);
1366 	if (IS_ERR(port)) {
1367 		dev_err(&pdev->dev, "Invalid line %d\n", line);
1368 		return PTR_ERR(port);
1369 	}
1370 
1371 	uport = &port->uport;
1372 	/* Don't allow 2 drivers to access the same port */
1373 	if (uport->private_data)
1374 		return -ENODEV;
1375 
1376 	uport->dev = &pdev->dev;
1377 	port->se.dev = &pdev->dev;
1378 	port->se.wrapper = dev_get_drvdata(pdev->dev.parent);
1379 	port->se.clk = devm_clk_get(&pdev->dev, "se");
1380 	if (IS_ERR(port->se.clk)) {
1381 		ret = PTR_ERR(port->se.clk);
1382 		dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret);
1383 		return ret;
1384 	}
1385 
1386 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1387 	if (!res)
1388 		return -EINVAL;
1389 	uport->mapbase = res->start;
1390 
1391 	port->tx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1392 	port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1393 	port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;
1394 
1395 	if (!console) {
1396 		port->rx_fifo = devm_kcalloc(uport->dev,
1397 			port->rx_fifo_depth, sizeof(u32), GFP_KERNEL);
1398 		if (!port->rx_fifo)
1399 			return -ENOMEM;
1400 	}
1401 
1402 	ret = geni_icc_get(&port->se, NULL);
1403 	if (ret)
1404 		return ret;
1405 	port->se.icc_paths[GENI_TO_CORE].avg_bw = GENI_DEFAULT_BW;
1406 	port->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
1407 
1408 	/* Set BW for register access */
1409 	ret = geni_icc_set_bw(&port->se);
1410 	if (ret)
1411 		return ret;
1412 
1413 	port->name = devm_kasprintf(uport->dev, GFP_KERNEL,
1414 			"qcom_geni_serial_%s%d",
1415 			uart_console(uport) ? "console" : "uart", uport->line);
1416 	if (!port->name)
1417 		return -ENOMEM;
1418 
1419 	irq = platform_get_irq(pdev, 0);
1420 	if (irq < 0)
1421 		return irq;
1422 	uport->irq = irq;
1423 	uport->has_sysrq = IS_ENABLED(CONFIG_SERIAL_QCOM_GENI_CONSOLE);
1424 
1425 	if (!console)
1426 		port->wakeup_irq = platform_get_irq_optional(pdev, 1);
1427 
1428 	if (of_property_read_bool(pdev->dev.of_node, "rx-tx-swap"))
1429 		port->rx_tx_swap = true;
1430 
1431 	if (of_property_read_bool(pdev->dev.of_node, "cts-rts-swap"))
1432 		port->cts_rts_swap = true;
1433 
1434 	ret = devm_pm_opp_set_clkname(&pdev->dev, "se");
1435 	if (ret)
1436 		return ret;
1437 	/* OPP table is optional */
1438 	ret = devm_pm_opp_of_add_table(&pdev->dev);
1439 	if (ret && ret != -ENODEV) {
1440 		dev_err(&pdev->dev, "invalid OPP table in device tree\n");
1441 		return ret;
1442 	}
1443 
1444 	port->private_data.drv = drv;
1445 	uport->private_data = &port->private_data;
1446 	platform_set_drvdata(pdev, port);
1447 	port->handle_rx = console ? handle_rx_console : handle_rx_uart;
1448 
1449 	ret = uart_add_one_port(drv, uport);
1450 	if (ret)
1451 		return ret;
1452 
1453 	irq_set_status_flags(uport->irq, IRQ_NOAUTOEN);
1454 	ret = devm_request_irq(uport->dev, uport->irq, qcom_geni_serial_isr,
1455 			IRQF_TRIGGER_HIGH, port->name, uport);
1456 	if (ret) {
1457 		dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret);
1458 		uart_remove_one_port(drv, uport);
1459 		return ret;
1460 	}
1461 
1462 	/*
1463 	 * Set pm_runtime status as ACTIVE so that wakeup_irq gets
1464 	 * enabled/disabled from dev_pm_arm_wake_irq during system
1465 	 * suspend/resume respectively.
1466 	 */
1467 	pm_runtime_set_active(&pdev->dev);
1468 
1469 	if (port->wakeup_irq > 0) {
1470 		device_init_wakeup(&pdev->dev, true);
1471 		ret = dev_pm_set_dedicated_wake_irq(&pdev->dev,
1472 						port->wakeup_irq);
1473 		if (ret) {
1474 			device_init_wakeup(&pdev->dev, false);
1475 			uart_remove_one_port(drv, uport);
1476 			return ret;
1477 		}
1478 	}
1479 
1480 	return 0;
1481 }
1482 
1483 static int qcom_geni_serial_remove(struct platform_device *pdev)
1484 {
1485 	struct qcom_geni_serial_port *port = platform_get_drvdata(pdev);
1486 	struct uart_driver *drv = port->private_data.drv;
1487 
1488 	dev_pm_clear_wake_irq(&pdev->dev);
1489 	device_init_wakeup(&pdev->dev, false);
1490 	uart_remove_one_port(drv, &port->uport);
1491 
1492 	return 0;
1493 }
1494 
1495 static int __maybe_unused qcom_geni_serial_sys_suspend(struct device *dev)
1496 {
1497 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1498 	struct uart_port *uport = &port->uport;
1499 	struct qcom_geni_private_data *private_data = uport->private_data;
1500 
1501 	/*
1502 	 * This is done so we can hit the lowest possible state in suspend
1503 	 * even with no_console_suspend
1504 	 */
1505 	if (uart_console(uport)) {
1506 		geni_icc_set_tag(&port->se, 0x3);
1507 		geni_icc_set_bw(&port->se);
1508 	}
1509 	return uart_suspend_port(private_data->drv, uport);
1510 }
1511 
1512 static int __maybe_unused qcom_geni_serial_sys_resume(struct device *dev)
1513 {
1514 	int ret;
1515 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1516 	struct uart_port *uport = &port->uport;
1517 	struct qcom_geni_private_data *private_data = uport->private_data;
1518 
1519 	ret = uart_resume_port(private_data->drv, uport);
1520 	if (uart_console(uport)) {
1521 		geni_icc_set_tag(&port->se, 0x7);
1522 		geni_icc_set_bw(&port->se);
1523 	}
1524 	return ret;
1525 }
1526 
1527 static const struct dev_pm_ops qcom_geni_serial_pm_ops = {
1528 	SET_SYSTEM_SLEEP_PM_OPS(qcom_geni_serial_sys_suspend,
1529 					qcom_geni_serial_sys_resume)
1530 };
1531 
1532 static const struct of_device_id qcom_geni_serial_match_table[] = {
1533 	{ .compatible = "qcom,geni-debug-uart", },
1534 	{ .compatible = "qcom,geni-uart", },
1535 	{}
1536 };
1537 MODULE_DEVICE_TABLE(of, qcom_geni_serial_match_table);
1538 
1539 static struct platform_driver qcom_geni_serial_platform_driver = {
1540 	.remove = qcom_geni_serial_remove,
1541 	.probe = qcom_geni_serial_probe,
1542 	.driver = {
1543 		.name = "qcom_geni_serial",
1544 		.of_match_table = qcom_geni_serial_match_table,
1545 		.pm = &qcom_geni_serial_pm_ops,
1546 	},
1547 };
1548 
1549 static int __init qcom_geni_serial_init(void)
1550 {
1551 	int ret;
1552 
1553 	ret = console_register(&qcom_geni_console_driver);
1554 	if (ret)
1555 		return ret;
1556 
1557 	ret = uart_register_driver(&qcom_geni_uart_driver);
1558 	if (ret) {
1559 		console_unregister(&qcom_geni_console_driver);
1560 		return ret;
1561 	}
1562 
1563 	ret = platform_driver_register(&qcom_geni_serial_platform_driver);
1564 	if (ret) {
1565 		console_unregister(&qcom_geni_console_driver);
1566 		uart_unregister_driver(&qcom_geni_uart_driver);
1567 	}
1568 	return ret;
1569 }
1570 module_init(qcom_geni_serial_init);
1571 
1572 static void __exit qcom_geni_serial_exit(void)
1573 {
1574 	platform_driver_unregister(&qcom_geni_serial_platform_driver);
1575 	console_unregister(&qcom_geni_console_driver);
1576 	uart_unregister_driver(&qcom_geni_uart_driver);
1577 }
1578 module_exit(qcom_geni_serial_exit);
1579 
1580 MODULE_DESCRIPTION("Serial driver for GENI based QUP cores");
1581 MODULE_LICENSE("GPL v2");
1582