xref: /linux/drivers/tty/serial/qcom_geni_serial.c (revision 2d2640712455fc1c9a0bab0196404e27cf48d1af)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
4  * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
5  */
6 
7 /* Disable MMIO tracing to prevent excessive logging of unwanted MMIO traces */
8 #define __DISABLE_TRACE_MMIO__
9 
10 #include <linux/clk.h>
11 #include <linux/console.h>
12 #include <linux/io.h>
13 #include <linux/iopoll.h>
14 #include <linux/irq.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/pm_domain.h>
18 #include <linux/pm_opp.h>
19 #include <linux/platform_device.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/pm_wakeirq.h>
22 #include <linux/soc/qcom/geni-se.h>
23 #include <linux/serial.h>
24 #include <linux/serial_core.h>
25 #include <linux/slab.h>
26 #include <linux/tty.h>
27 #include <linux/tty_flip.h>
28 #include <dt-bindings/interconnect/qcom,icc.h>
29 
30 /* UART specific GENI registers */
31 #define SE_UART_LOOPBACK_CFG		0x22c
32 #define SE_UART_IO_MACRO_CTRL		0x240
33 #define SE_UART_TX_TRANS_CFG		0x25c
34 #define SE_UART_TX_WORD_LEN		0x268
35 #define SE_UART_TX_STOP_BIT_LEN		0x26c
36 #define SE_UART_TX_TRANS_LEN		0x270
37 #define SE_UART_RX_TRANS_CFG		0x280
38 #define SE_UART_RX_WORD_LEN		0x28c
39 #define SE_UART_RX_STALE_CNT		0x294
40 #define SE_UART_TX_PARITY_CFG		0x2a4
41 #define SE_UART_RX_PARITY_CFG		0x2a8
42 #define SE_UART_MANUAL_RFR		0x2ac
43 
44 /* SE_UART_TRANS_CFG */
45 #define UART_TX_PAR_EN			BIT(0)
46 #define UART_CTS_MASK			BIT(1)
47 
48 /* SE_UART_TX_STOP_BIT_LEN */
49 #define TX_STOP_BIT_LEN_1		0
50 #define TX_STOP_BIT_LEN_2		2
51 
52 /* SE_UART_RX_TRANS_CFG */
53 #define UART_RX_PAR_EN			BIT(3)
54 
55 /* SE_UART_RX_WORD_LEN */
56 #define RX_WORD_LEN_MASK		GENMASK(9, 0)
57 
58 /* SE_UART_RX_STALE_CNT */
59 #define RX_STALE_CNT			GENMASK(23, 0)
60 
61 /* SE_UART_TX_PARITY_CFG/RX_PARITY_CFG */
62 #define PAR_CALC_EN			BIT(0)
63 #define PAR_EVEN			0x00
64 #define PAR_ODD				0x01
65 #define PAR_SPACE			0x10
66 
67 /* SE_UART_MANUAL_RFR register fields */
68 #define UART_MANUAL_RFR_EN		BIT(31)
69 #define UART_RFR_NOT_READY		BIT(1)
70 #define UART_RFR_READY			BIT(0)
71 
72 /* UART M_CMD OP codes */
73 #define UART_START_TX			0x1
74 /* UART S_CMD OP codes */
75 #define UART_START_READ			0x1
76 #define UART_PARAM			0x1
77 #define UART_PARAM_RFR_OPEN		BIT(7)
78 
79 #define UART_OVERSAMPLING		32
80 #define STALE_TIMEOUT			16
81 #define DEFAULT_BITS_PER_CHAR		10
82 #define GENI_UART_CONS_PORTS		1
83 #define DEF_FIFO_DEPTH_WORDS		16
84 #define DEF_TX_WM			2
85 #define DEF_FIFO_WIDTH_BITS		32
86 #define UART_RX_WM			2
87 
88 /* SE_UART_LOOPBACK_CFG */
89 #define RX_TX_SORTED			BIT(0)
90 #define CTS_RTS_SORTED			BIT(1)
91 #define RX_TX_CTS_RTS_SORTED		(RX_TX_SORTED | CTS_RTS_SORTED)
92 
93 /* UART pin swap value */
94 #define DEFAULT_IO_MACRO_IO0_IO1_MASK	GENMASK(3, 0)
95 #define IO_MACRO_IO0_SEL		0x3
96 #define DEFAULT_IO_MACRO_IO2_IO3_MASK	GENMASK(15, 4)
97 #define IO_MACRO_IO2_IO3_SWAP		0x4640
98 
99 /* We always configure 4 bytes per FIFO word */
100 #define BYTES_PER_FIFO_WORD		4U
101 
102 #define DMA_RX_BUF_SIZE		2048
103 
104 static DEFINE_IDA(port_ida);
105 #define DOMAIN_IDX_POWER	0
106 #define DOMAIN_IDX_PERF		1
107 
108 struct qcom_geni_device_data {
109 	bool console;
110 	enum geni_se_xfer_mode mode;
111 	struct dev_pm_domain_attach_data pd_data;
112 	int (*resources_init)(struct uart_port *uport);
113 	int (*set_rate)(struct uart_port *uport, unsigned int baud);
114 	int (*power_state)(struct uart_port *uport, bool state);
115 };
116 
117 struct qcom_geni_private_data {
118 	/* NOTE: earlycon port will have NULL here */
119 	struct uart_driver *drv;
120 
121 	u32 poll_cached_bytes;
122 	unsigned int poll_cached_bytes_cnt;
123 
124 	u32 write_cached_bytes;
125 	unsigned int write_cached_bytes_cnt;
126 };
127 
128 struct qcom_geni_serial_port {
129 	struct uart_port uport;
130 	struct geni_se se;
131 	const char *name;
132 	u32 tx_fifo_depth;
133 	u32 tx_fifo_width;
134 	u32 rx_fifo_depth;
135 	dma_addr_t tx_dma_addr;
136 	dma_addr_t rx_dma_addr;
137 	bool setup;
138 	unsigned long poll_timeout_us;
139 	unsigned long clk_rate;
140 	void *rx_buf;
141 	u32 loopback;
142 	bool brk;
143 
144 	unsigned int tx_remaining;
145 	unsigned int tx_queued;
146 	int wakeup_irq;
147 	bool rx_tx_swap;
148 	bool cts_rts_swap;
149 	bool manual_flow;
150 
151 	struct qcom_geni_private_data private_data;
152 	const struct qcom_geni_device_data *dev_data;
153 	struct dev_pm_domain_list *pd_list;
154 };
155 
156 static const struct uart_ops qcom_geni_console_pops;
157 static const struct uart_ops qcom_geni_uart_pops;
158 static struct uart_driver qcom_geni_console_driver;
159 static struct uart_driver qcom_geni_uart_driver;
160 
161 static void __qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport);
162 static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport);
163 static int qcom_geni_serial_port_setup(struct uart_port *uport);
164 
165 static inline struct qcom_geni_serial_port *to_dev_port(struct uart_port *uport)
166 {
167 	return container_of(uport, struct qcom_geni_serial_port, uport);
168 }
169 
170 static struct qcom_geni_serial_port qcom_geni_console_port = {
171 	.uport = {
172 		.iotype = UPIO_MEM,
173 		.ops = &qcom_geni_console_pops,
174 		.flags = UPF_BOOT_AUTOCONF,
175 		.line = 0,
176 	},
177 };
178 
179 static const struct serial_rs485 qcom_geni_rs485_supported = {
180 	.flags = SER_RS485_ENABLED | SER_RS485_RTS_AFTER_SEND | SER_RS485_RTS_ON_SEND,
181 };
182 
183 /**
184  * qcom_geni_set_rs485_mode - Set RTS pin state for RS485 mode
185  * @uport: UART port
186  * @flag: RS485 flag to determine RTS polarity
187  *
188  * Enables manual RTS control for RS485. Sets RTS to READY or NOT_READY
189  * based on the specified flag if RS485 mode is enabled.
190  */
191 static void qcom_geni_set_rs485_mode(struct uart_port *uport, u32 flag)
192 {
193 	if (!(uport->rs485.flags & SER_RS485_ENABLED))
194 		return;
195 
196 	u32 rfr = UART_MANUAL_RFR_EN;
197 
198 	if (uport->rs485.flags & flag)
199 		rfr |= UART_RFR_NOT_READY;
200 	else
201 		rfr |= UART_RFR_READY;
202 
203 	writel(rfr, uport->membase + SE_UART_MANUAL_RFR);
204 }
205 
206 static int qcom_geni_serial_request_port(struct uart_port *uport)
207 {
208 	struct platform_device *pdev = to_platform_device(uport->dev);
209 	struct qcom_geni_serial_port *port = to_dev_port(uport);
210 
211 	uport->membase = devm_platform_ioremap_resource(pdev, 0);
212 	if (IS_ERR(uport->membase))
213 		return PTR_ERR(uport->membase);
214 	port->se.base = uport->membase;
215 	return 0;
216 }
217 
218 static void qcom_geni_serial_config_port(struct uart_port *uport, int cfg_flags)
219 {
220 	if (cfg_flags & UART_CONFIG_TYPE) {
221 		uport->type = PORT_MSM;
222 		qcom_geni_serial_request_port(uport);
223 	}
224 }
225 
226 static unsigned int qcom_geni_serial_get_mctrl(struct uart_port *uport)
227 {
228 	unsigned int mctrl = TIOCM_DSR | TIOCM_CAR;
229 	u32 geni_ios;
230 
231 	if (uart_console(uport)) {
232 		mctrl |= TIOCM_CTS;
233 	} else {
234 		geni_ios = readl(uport->membase + SE_GENI_IOS);
235 		if (!(geni_ios & IO2_DATA_IN))
236 			mctrl |= TIOCM_CTS;
237 	}
238 
239 	return mctrl;
240 }
241 
242 static void qcom_geni_serial_set_mctrl(struct uart_port *uport,
243 							unsigned int mctrl)
244 {
245 	u32 uart_manual_rfr = 0;
246 	struct qcom_geni_serial_port *port = to_dev_port(uport);
247 
248 	if (uart_console(uport))
249 		return;
250 
251 	if (mctrl & TIOCM_LOOP)
252 		port->loopback = RX_TX_CTS_RTS_SORTED;
253 
254 	if (port->manual_flow && !(mctrl & TIOCM_RTS) && !uport->suspended)
255 		uart_manual_rfr = UART_MANUAL_RFR_EN | UART_RFR_NOT_READY;
256 	writel(uart_manual_rfr, uport->membase + SE_UART_MANUAL_RFR);
257 }
258 
259 static const char *qcom_geni_serial_get_type(struct uart_port *uport)
260 {
261 	return "MSM";
262 }
263 
264 static struct qcom_geni_serial_port *get_port_from_line(int line, bool console, struct device *dev)
265 {
266 	struct qcom_geni_serial_port *port;
267 	int nr_ports = console ? GENI_UART_CONS_PORTS : CONFIG_SERIAL_QCOM_GENI_UART_PORTS;
268 
269 	if (console) {
270 		if (line < 0 || line >= nr_ports)
271 			return ERR_PTR(-ENXIO);
272 
273 		port = &qcom_geni_console_port;
274 	} else {
275 		int max_alias_num = of_alias_get_highest_id("serial");
276 
277 		if (line < 0 || line >= nr_ports)
278 			line = ida_alloc_range(&port_ida, max_alias_num + 1,
279 					       nr_ports - 1, GFP_KERNEL);
280 		else
281 			line = ida_alloc_range(&port_ida, line,
282 					       nr_ports - 1, GFP_KERNEL);
283 
284 		if (line < 0)
285 			return ERR_PTR(-ENXIO);
286 
287 		port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
288 		if (!port)
289 			return ERR_PTR(-ENOMEM);
290 
291 		port->uport.iotype = UPIO_MEM;
292 		port->uport.ops = &qcom_geni_uart_pops;
293 		port->uport.flags = UPF_BOOT_AUTOCONF;
294 		port->uport.line = line;
295 	}
296 	return port;
297 }
298 
299 static bool qcom_geni_serial_main_active(struct uart_port *uport)
300 {
301 	return readl(uport->membase + SE_GENI_STATUS) & M_GENI_CMD_ACTIVE;
302 }
303 
304 static bool qcom_geni_serial_secondary_active(struct uart_port *uport)
305 {
306 	return readl(uport->membase + SE_GENI_STATUS) & S_GENI_CMD_ACTIVE;
307 }
308 
309 static bool qcom_geni_serial_poll_bitfield(struct uart_port *uport,
310 					   unsigned int offset, u32 field, u32 val)
311 {
312 	u32 reg;
313 	struct qcom_geni_serial_port *port;
314 	unsigned long timeout_us = 20000;
315 	struct qcom_geni_private_data *private_data = uport->private_data;
316 
317 	if (private_data->drv) {
318 		port = to_dev_port(uport);
319 		if (port->poll_timeout_us)
320 			timeout_us = port->poll_timeout_us;
321 	}
322 
323 	/*
324 	 * Use custom implementation instead of readl_poll_atomic since ktimer
325 	 * is not ready at the time of early console.
326 	 */
327 	timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10;
328 	while (timeout_us) {
329 		reg = readl(uport->membase + offset);
330 		if ((reg & field) == val)
331 			return true;
332 		udelay(10);
333 		timeout_us -= 10;
334 	}
335 	return false;
336 }
337 
338 static bool qcom_geni_serial_poll_bit(struct uart_port *uport,
339 				      unsigned int offset, u32 field, bool set)
340 {
341 	return qcom_geni_serial_poll_bitfield(uport, offset, field, set ? field : 0);
342 }
343 
344 static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size)
345 {
346 	u32 m_cmd;
347 
348 	writel(xmit_size, uport->membase + SE_UART_TX_TRANS_LEN);
349 	m_cmd = UART_START_TX << M_OPCODE_SHFT;
350 	writel(m_cmd, uport->membase + SE_GENI_M_CMD0);
351 }
352 
353 static void qcom_geni_serial_poll_tx_done(struct uart_port *uport)
354 {
355 	int done;
356 
357 	done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
358 						M_CMD_DONE_EN, true);
359 	if (!done) {
360 		writel(M_GENI_CMD_ABORT, uport->membase +
361 						SE_GENI_M_CMD_CTRL_REG);
362 		qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
363 							M_CMD_ABORT_EN, true);
364 		writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
365 	}
366 }
367 
368 static void qcom_geni_serial_abort_rx(struct uart_port *uport)
369 {
370 	u32 irq_clear = S_CMD_DONE_EN | S_CMD_ABORT_EN;
371 
372 	writel(S_GENI_CMD_ABORT, uport->membase + SE_GENI_S_CMD_CTRL_REG);
373 	qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG,
374 					S_GENI_CMD_ABORT, false);
375 	writel(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR);
376 	writel(FORCE_DEFAULT, uport->membase + GENI_FORCE_DEFAULT_REG);
377 }
378 
379 #ifdef CONFIG_CONSOLE_POLL
380 static int qcom_geni_serial_get_char(struct uart_port *uport)
381 {
382 	struct qcom_geni_private_data *private_data = uport->private_data;
383 	u32 status;
384 	u32 word_cnt;
385 	int ret;
386 
387 	if (!private_data->poll_cached_bytes_cnt) {
388 		status = readl(uport->membase + SE_GENI_M_IRQ_STATUS);
389 		writel(status, uport->membase + SE_GENI_M_IRQ_CLEAR);
390 
391 		status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
392 		writel(status, uport->membase + SE_GENI_S_IRQ_CLEAR);
393 
394 		status = readl(uport->membase + SE_GENI_RX_FIFO_STATUS);
395 		word_cnt = status & RX_FIFO_WC_MSK;
396 		if (!word_cnt)
397 			return NO_POLL_CHAR;
398 
399 		if (word_cnt == 1 && (status & RX_LAST))
400 			/*
401 			 * NOTE: If RX_LAST_BYTE_VALID is 0 it needs to be
402 			 * treated as if it was BYTES_PER_FIFO_WORD.
403 			 */
404 			private_data->poll_cached_bytes_cnt =
405 				(status & RX_LAST_BYTE_VALID_MSK) >>
406 				RX_LAST_BYTE_VALID_SHFT;
407 
408 		if (private_data->poll_cached_bytes_cnt == 0)
409 			private_data->poll_cached_bytes_cnt = BYTES_PER_FIFO_WORD;
410 
411 		private_data->poll_cached_bytes =
412 			readl(uport->membase + SE_GENI_RX_FIFOn);
413 	}
414 
415 	private_data->poll_cached_bytes_cnt--;
416 	ret = private_data->poll_cached_bytes & 0xff;
417 	private_data->poll_cached_bytes >>= 8;
418 
419 	return ret;
420 }
421 
422 static void qcom_geni_serial_poll_put_char(struct uart_port *uport,
423 							unsigned char c)
424 {
425 	if (qcom_geni_serial_main_active(uport)) {
426 		qcom_geni_serial_poll_tx_done(uport);
427 		__qcom_geni_serial_cancel_tx_cmd(uport);
428 	}
429 
430 	writel(M_CMD_DONE_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
431 	qcom_geni_serial_setup_tx(uport, 1);
432 	writel(c, uport->membase + SE_GENI_TX_FIFOn);
433 	qcom_geni_serial_poll_tx_done(uport);
434 }
435 
436 static int qcom_geni_serial_poll_init(struct uart_port *uport)
437 {
438 	struct qcom_geni_serial_port *port = to_dev_port(uport);
439 	int ret;
440 
441 	if (!port->setup) {
442 		ret = qcom_geni_serial_port_setup(uport);
443 		if (ret)
444 			return ret;
445 	}
446 
447 	if (!qcom_geni_serial_secondary_active(uport))
448 		geni_se_setup_s_cmd(&port->se, UART_START_READ, 0);
449 
450 	return 0;
451 }
452 #endif
453 
454 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
455 static void qcom_geni_serial_drain_fifo(struct uart_port *uport)
456 {
457 	struct qcom_geni_serial_port *port = to_dev_port(uport);
458 
459 	qcom_geni_serial_poll_bitfield(uport, SE_GENI_M_GP_LENGTH, GP_LENGTH,
460 			port->tx_queued);
461 }
462 
463 static void qcom_geni_serial_wr_char(struct uart_port *uport, unsigned char ch)
464 {
465 	struct qcom_geni_private_data *private_data = uport->private_data;
466 
467 	private_data->write_cached_bytes =
468 		(private_data->write_cached_bytes >> 8) | (ch << 24);
469 	private_data->write_cached_bytes_cnt++;
470 
471 	if (private_data->write_cached_bytes_cnt == BYTES_PER_FIFO_WORD) {
472 		writel(private_data->write_cached_bytes,
473 		       uport->membase + SE_GENI_TX_FIFOn);
474 		private_data->write_cached_bytes_cnt = 0;
475 	}
476 }
477 
478 static void
479 __qcom_geni_serial_console_write(struct uart_port *uport, const char *s,
480 				 unsigned int count)
481 {
482 	struct qcom_geni_private_data *private_data = uport->private_data;
483 
484 	int i;
485 	u32 bytes_to_send = count;
486 
487 	for (i = 0; i < count; i++) {
488 		/*
489 		 * uart_console_write() adds a carriage return for each newline.
490 		 * Account for additional bytes to be written.
491 		 */
492 		if (s[i] == '\n')
493 			bytes_to_send++;
494 	}
495 
496 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
497 	writel(M_CMD_DONE_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
498 	qcom_geni_serial_setup_tx(uport, bytes_to_send);
499 	for (i = 0; i < count; ) {
500 		size_t chars_to_write = 0;
501 		size_t avail = DEF_FIFO_DEPTH_WORDS - DEF_TX_WM;
502 
503 		/*
504 		 * If the WM bit never set, then the Tx state machine is not
505 		 * in a valid state, so break, cancel/abort any existing
506 		 * command. Unfortunately the current data being written is
507 		 * lost.
508 		 */
509 		if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
510 						M_TX_FIFO_WATERMARK_EN, true))
511 			break;
512 		chars_to_write = min_t(size_t, count - i, avail / 2);
513 		uart_console_write(uport, s + i, chars_to_write,
514 						qcom_geni_serial_wr_char);
515 		writel(M_TX_FIFO_WATERMARK_EN, uport->membase +
516 							SE_GENI_M_IRQ_CLEAR);
517 		i += chars_to_write;
518 	}
519 
520 	if (private_data->write_cached_bytes_cnt) {
521 		private_data->write_cached_bytes >>= BITS_PER_BYTE *
522 			(BYTES_PER_FIFO_WORD - private_data->write_cached_bytes_cnt);
523 		writel(private_data->write_cached_bytes,
524 		       uport->membase + SE_GENI_TX_FIFOn);
525 		private_data->write_cached_bytes_cnt = 0;
526 	}
527 
528 	qcom_geni_serial_poll_tx_done(uport);
529 }
530 
531 static void qcom_geni_serial_console_write(struct console *co, const char *s,
532 			      unsigned int count)
533 {
534 	struct uart_port *uport;
535 	struct qcom_geni_serial_port *port;
536 	u32 m_irq_en, s_irq_en;
537 	bool locked = true;
538 	unsigned long flags;
539 
540 	WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS);
541 
542 	port = get_port_from_line(co->index, true, NULL);
543 	if (IS_ERR(port))
544 		return;
545 
546 	uport = &port->uport;
547 	if (oops_in_progress)
548 		locked = uart_port_trylock_irqsave(uport, &flags);
549 	else
550 		uart_port_lock_irqsave(uport, &flags);
551 
552 	m_irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
553 	s_irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
554 	writel(0, uport->membase + SE_GENI_M_IRQ_EN);
555 	writel(0, uport->membase + SE_GENI_S_IRQ_EN);
556 
557 	if (qcom_geni_serial_main_active(uport)) {
558 		/* Wait for completion or drain FIFO */
559 		if (!locked || port->tx_remaining == 0)
560 			qcom_geni_serial_poll_tx_done(uport);
561 		else
562 			qcom_geni_serial_drain_fifo(uport);
563 
564 		qcom_geni_serial_cancel_tx_cmd(uport);
565 	}
566 
567 	__qcom_geni_serial_console_write(uport, s, count);
568 
569 	writel(m_irq_en, uport->membase + SE_GENI_M_IRQ_EN);
570 	writel(s_irq_en, uport->membase + SE_GENI_S_IRQ_EN);
571 
572 	if (locked)
573 		uart_port_unlock_irqrestore(uport, flags);
574 }
575 
576 static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
577 {
578 	u32 i;
579 	unsigned char buf[sizeof(u32)];
580 	struct tty_port *tport;
581 	struct qcom_geni_serial_port *port = to_dev_port(uport);
582 
583 	tport = &uport->state->port;
584 	for (i = 0; i < bytes; ) {
585 		int c;
586 		int chunk = min_t(int, bytes - i, BYTES_PER_FIFO_WORD);
587 
588 		ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1);
589 		i += chunk;
590 		if (drop)
591 			continue;
592 
593 		for (c = 0; c < chunk; c++) {
594 			int sysrq;
595 
596 			uport->icount.rx++;
597 			if (port->brk && buf[c] == 0) {
598 				port->brk = false;
599 				if (uart_handle_break(uport))
600 					continue;
601 			}
602 
603 			sysrq = uart_prepare_sysrq_char(uport, buf[c]);
604 
605 			if (!sysrq)
606 				tty_insert_flip_char(tport, buf[c], TTY_NORMAL);
607 		}
608 	}
609 	if (!drop)
610 		tty_flip_buffer_push(tport);
611 }
612 #else
613 static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
614 {
615 
616 }
617 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
618 
619 static void handle_rx_uart(struct uart_port *uport, u32 bytes)
620 {
621 	struct qcom_geni_serial_port *port = to_dev_port(uport);
622 	struct tty_port *tport = &uport->state->port;
623 	int ret;
624 
625 	ret = tty_insert_flip_string(tport, port->rx_buf, bytes);
626 	if (ret != bytes) {
627 		dev_err_ratelimited(uport->dev, "failed to push data (%d < %u)\n",
628 				ret, bytes);
629 	}
630 	uport->icount.rx += ret;
631 	tty_flip_buffer_push(tport);
632 }
633 
634 static unsigned int qcom_geni_serial_tx_empty(struct uart_port *uport)
635 {
636 	return !readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
637 }
638 
639 static void qcom_geni_serial_stop_tx_dma(struct uart_port *uport)
640 {
641 	struct qcom_geni_serial_port *port = to_dev_port(uport);
642 	bool done;
643 
644 	if (!qcom_geni_serial_main_active(uport))
645 		return;
646 
647 	if (port->tx_dma_addr) {
648 		geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr,
649 				      port->tx_remaining);
650 		port->tx_dma_addr = 0;
651 		port->tx_remaining = 0;
652 	}
653 
654 	geni_se_cancel_m_cmd(&port->se);
655 
656 	done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
657 					 M_CMD_CANCEL_EN, true);
658 	if (!done) {
659 		geni_se_abort_m_cmd(&port->se);
660 		done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
661 						 M_CMD_ABORT_EN, true);
662 		if (!done)
663 			dev_err_ratelimited(uport->dev, "M_CMD_ABORT_EN not set");
664 		writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
665 	}
666 
667 	writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
668 }
669 
670 static void qcom_geni_serial_start_tx_dma(struct uart_port *uport)
671 {
672 	struct qcom_geni_serial_port *port = to_dev_port(uport);
673 	struct tty_port *tport = &uport->state->port;
674 	unsigned int xmit_size;
675 	u8 *tail;
676 	int ret;
677 
678 	if (port->tx_dma_addr)
679 		return;
680 
681 	if (kfifo_is_empty(&tport->xmit_fifo))
682 		return;
683 
684 	xmit_size = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail,
685 			UART_XMIT_SIZE);
686 
687 	qcom_geni_set_rs485_mode(uport, SER_RS485_RTS_ON_SEND);
688 
689 	qcom_geni_serial_setup_tx(uport, xmit_size);
690 
691 	ret = geni_se_tx_dma_prep(&port->se, tail, xmit_size,
692 				  &port->tx_dma_addr);
693 	if (ret) {
694 		dev_err(uport->dev, "unable to start TX SE DMA: %d\n", ret);
695 		qcom_geni_serial_stop_tx_dma(uport);
696 		return;
697 	}
698 
699 	port->tx_remaining = xmit_size;
700 }
701 
702 static void qcom_geni_serial_start_tx_fifo(struct uart_port *uport)
703 {
704 	unsigned char c;
705 	u32 irq_en;
706 
707 	/*
708 	 * Start a new transfer in case the previous command was cancelled and
709 	 * left data in the FIFO which may prevent the watermark interrupt
710 	 * from triggering. Note that the stale data is discarded.
711 	 */
712 	if (!qcom_geni_serial_main_active(uport) &&
713 	    !qcom_geni_serial_tx_empty(uport)) {
714 		if (uart_fifo_out(uport, &c, 1) == 1) {
715 			writel(M_CMD_DONE_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
716 			qcom_geni_serial_setup_tx(uport, 1);
717 			writel(c, uport->membase + SE_GENI_TX_FIFOn);
718 		}
719 	}
720 
721 	irq_en = readl(uport->membase +	SE_GENI_M_IRQ_EN);
722 	irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
723 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
724 	writel(irq_en, uport->membase +	SE_GENI_M_IRQ_EN);
725 }
726 
727 static void qcom_geni_serial_stop_tx_fifo(struct uart_port *uport)
728 {
729 	u32 irq_en;
730 
731 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
732 	irq_en &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
733 	writel(0, uport->membase + SE_GENI_TX_WATERMARK_REG);
734 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
735 }
736 
737 static void __qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport)
738 {
739 	struct qcom_geni_serial_port *port = to_dev_port(uport);
740 
741 	geni_se_cancel_m_cmd(&port->se);
742 	if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
743 						M_CMD_CANCEL_EN, true)) {
744 		geni_se_abort_m_cmd(&port->se);
745 		qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
746 						M_CMD_ABORT_EN, true);
747 		writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
748 	}
749 	writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
750 }
751 
752 static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport)
753 {
754 	struct qcom_geni_serial_port *port = to_dev_port(uport);
755 
756 	if (!qcom_geni_serial_main_active(uport))
757 		return;
758 
759 	__qcom_geni_serial_cancel_tx_cmd(uport);
760 
761 	port->tx_remaining = 0;
762 	port->tx_queued = 0;
763 }
764 
765 static void qcom_geni_serial_handle_rx_fifo(struct uart_port *uport, bool drop)
766 {
767 	u32 status;
768 	u32 word_cnt;
769 	u32 last_word_byte_cnt;
770 	u32 last_word_partial;
771 	u32 total_bytes;
772 
773 	status = readl(uport->membase +	SE_GENI_RX_FIFO_STATUS);
774 	word_cnt = status & RX_FIFO_WC_MSK;
775 	last_word_partial = status & RX_LAST;
776 	last_word_byte_cnt = (status & RX_LAST_BYTE_VALID_MSK) >>
777 						RX_LAST_BYTE_VALID_SHFT;
778 
779 	if (!word_cnt)
780 		return;
781 	total_bytes = BYTES_PER_FIFO_WORD * (word_cnt - 1);
782 	if (last_word_partial && last_word_byte_cnt)
783 		total_bytes += last_word_byte_cnt;
784 	else
785 		total_bytes += BYTES_PER_FIFO_WORD;
786 	handle_rx_console(uport, total_bytes, drop);
787 }
788 
789 static void qcom_geni_serial_stop_rx_fifo(struct uart_port *uport)
790 {
791 	u32 irq_en;
792 	struct qcom_geni_serial_port *port = to_dev_port(uport);
793 	u32 s_irq_status;
794 
795 	irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
796 	irq_en &= ~(S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN);
797 	writel(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
798 
799 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
800 	irq_en &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
801 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
802 
803 	if (!qcom_geni_serial_secondary_active(uport))
804 		return;
805 
806 	geni_se_cancel_s_cmd(&port->se);
807 	qcom_geni_serial_poll_bit(uport, SE_GENI_S_IRQ_STATUS,
808 					S_CMD_CANCEL_EN, true);
809 	/*
810 	 * If timeout occurs secondary engine remains active
811 	 * and Abort sequence is executed.
812 	 */
813 	s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
814 	/* Flush the Rx buffer */
815 	if (s_irq_status & S_RX_FIFO_LAST_EN)
816 		qcom_geni_serial_handle_rx_fifo(uport, true);
817 	writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
818 
819 	if (qcom_geni_serial_secondary_active(uport))
820 		qcom_geni_serial_abort_rx(uport);
821 }
822 
823 static void qcom_geni_serial_start_rx_fifo(struct uart_port *uport)
824 {
825 	u32 irq_en;
826 	struct qcom_geni_serial_port *port = to_dev_port(uport);
827 
828 	if (qcom_geni_serial_secondary_active(uport))
829 		qcom_geni_serial_stop_rx_fifo(uport);
830 
831 	geni_se_setup_s_cmd(&port->se, UART_START_READ, 0);
832 
833 	irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
834 	irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN;
835 	writel(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
836 
837 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
838 	irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
839 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
840 }
841 
842 static void qcom_geni_serial_stop_rx_dma(struct uart_port *uport)
843 {
844 	struct qcom_geni_serial_port *port = to_dev_port(uport);
845 	bool done;
846 
847 	if (!qcom_geni_serial_secondary_active(uport))
848 		return;
849 
850 	geni_se_cancel_s_cmd(&port->se);
851 	done = qcom_geni_serial_poll_bit(uport, SE_DMA_RX_IRQ_STAT,
852 			RX_EOT, true);
853 	if (done) {
854 		writel(RX_EOT | RX_DMA_DONE,
855 				uport->membase + SE_DMA_RX_IRQ_CLR);
856 	} else {
857 		qcom_geni_serial_abort_rx(uport);
858 
859 		writel(1, uport->membase + SE_DMA_RX_FSM_RST);
860 		qcom_geni_serial_poll_bit(uport, SE_DMA_RX_IRQ_STAT,
861 				RX_RESET_DONE, true);
862 		writel(RX_RESET_DONE | RX_DMA_DONE,
863 				uport->membase + SE_DMA_RX_IRQ_CLR);
864 	}
865 
866 	if (port->rx_dma_addr) {
867 		geni_se_rx_dma_unprep(&port->se, port->rx_dma_addr,
868 				      DMA_RX_BUF_SIZE);
869 		port->rx_dma_addr = 0;
870 	}
871 }
872 
873 static void qcom_geni_serial_start_rx_dma(struct uart_port *uport)
874 {
875 	struct qcom_geni_serial_port *port = to_dev_port(uport);
876 	int ret;
877 
878 	if (qcom_geni_serial_secondary_active(uport))
879 		qcom_geni_serial_stop_rx_dma(uport);
880 
881 	geni_se_setup_s_cmd(&port->se, UART_START_READ, UART_PARAM_RFR_OPEN);
882 
883 	ret = geni_se_rx_dma_prep(&port->se, port->rx_buf,
884 				  DMA_RX_BUF_SIZE,
885 				  &port->rx_dma_addr);
886 	if (ret) {
887 		dev_err(uport->dev, "unable to start RX SE DMA: %d\n", ret);
888 		qcom_geni_serial_stop_rx_dma(uport);
889 	}
890 }
891 
892 static void qcom_geni_serial_handle_rx_dma(struct uart_port *uport, bool drop)
893 {
894 	struct qcom_geni_serial_port *port = to_dev_port(uport);
895 	u32 rx_in;
896 	int ret;
897 
898 	if (!qcom_geni_serial_secondary_active(uport))
899 		return;
900 
901 	if (!port->rx_dma_addr)
902 		return;
903 
904 	geni_se_rx_dma_unprep(&port->se, port->rx_dma_addr, DMA_RX_BUF_SIZE);
905 	port->rx_dma_addr = 0;
906 
907 	rx_in = readl(uport->membase + SE_DMA_RX_LEN_IN);
908 	if (!rx_in) {
909 		dev_warn(uport->dev, "serial engine reports 0 RX bytes in!\n");
910 		return;
911 	}
912 
913 	if (!drop)
914 		handle_rx_uart(uport, rx_in);
915 
916 	ret = geni_se_rx_dma_prep(&port->se, port->rx_buf,
917 				  DMA_RX_BUF_SIZE,
918 				  &port->rx_dma_addr);
919 	if (ret) {
920 		dev_err(uport->dev, "unable to start RX SE DMA: %d\n", ret);
921 		qcom_geni_serial_stop_rx_dma(uport);
922 	}
923 }
924 
925 static void qcom_geni_serial_start_rx(struct uart_port *uport)
926 {
927 	uport->ops->start_rx(uport);
928 }
929 
930 static void qcom_geni_serial_stop_rx(struct uart_port *uport)
931 {
932 	uport->ops->stop_rx(uport);
933 }
934 
935 static void qcom_geni_serial_stop_tx(struct uart_port *uport)
936 {
937 	uport->ops->stop_tx(uport);
938 }
939 
940 static void qcom_geni_serial_send_chunk_fifo(struct uart_port *uport,
941 					     unsigned int chunk)
942 {
943 	struct qcom_geni_serial_port *port = to_dev_port(uport);
944 	unsigned int tx_bytes, remaining = chunk;
945 	u8 buf[BYTES_PER_FIFO_WORD];
946 
947 	while (remaining) {
948 		memset(buf, 0, sizeof(buf));
949 		tx_bytes = min(remaining, BYTES_PER_FIFO_WORD);
950 
951 		uart_fifo_out(uport, buf, tx_bytes);
952 
953 		iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
954 
955 		remaining -= tx_bytes;
956 		port->tx_remaining -= tx_bytes;
957 	}
958 }
959 
960 static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport,
961 					    bool done, bool active)
962 {
963 	struct qcom_geni_serial_port *port = to_dev_port(uport);
964 	struct tty_port *tport = &uport->state->port;
965 	size_t avail;
966 	size_t pending;
967 	u32 status;
968 	u32 irq_en;
969 	unsigned int chunk;
970 
971 	status = readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
972 
973 	/* Complete the current tx command before taking newly added data */
974 	if (active)
975 		pending = port->tx_remaining;
976 	else
977 		pending = kfifo_len(&tport->xmit_fifo);
978 
979 	/* All data has been transmitted or command has been cancelled */
980 	if (!pending && done) {
981 		qcom_geni_serial_stop_tx_fifo(uport);
982 		goto out_write_wakeup;
983 	}
984 
985 	if (active)
986 		avail = port->tx_fifo_depth - (status & TX_FIFO_WC);
987 	else
988 		avail = port->tx_fifo_depth;
989 
990 	avail *= BYTES_PER_FIFO_WORD;
991 
992 	chunk = min(avail, pending);
993 	if (!chunk)
994 		goto out_write_wakeup;
995 
996 	if (!active) {
997 		qcom_geni_serial_setup_tx(uport, pending);
998 		port->tx_remaining = pending;
999 		port->tx_queued = 0;
1000 
1001 		irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
1002 		if (!(irq_en & M_TX_FIFO_WATERMARK_EN))
1003 			writel(irq_en | M_TX_FIFO_WATERMARK_EN,
1004 					uport->membase + SE_GENI_M_IRQ_EN);
1005 	}
1006 
1007 	qcom_geni_serial_send_chunk_fifo(uport, chunk);
1008 	port->tx_queued += chunk;
1009 
1010 	/*
1011 	 * The tx fifo watermark is level triggered and latched. Though we had
1012 	 * cleared it in qcom_geni_serial_isr it will have already reasserted
1013 	 * so we must clear it again here after our writes.
1014 	 */
1015 	writel(M_TX_FIFO_WATERMARK_EN,
1016 			uport->membase + SE_GENI_M_IRQ_CLEAR);
1017 
1018 out_write_wakeup:
1019 	if (!port->tx_remaining) {
1020 		irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
1021 		if (irq_en & M_TX_FIFO_WATERMARK_EN)
1022 			writel(irq_en & ~M_TX_FIFO_WATERMARK_EN,
1023 					uport->membase + SE_GENI_M_IRQ_EN);
1024 	}
1025 
1026 	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
1027 		uart_write_wakeup(uport);
1028 }
1029 
1030 static void qcom_geni_serial_handle_tx_dma(struct uart_port *uport)
1031 {
1032 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1033 	struct tty_port *tport = &uport->state->port;
1034 
1035 	uart_xmit_advance(uport, port->tx_remaining);
1036 	geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr, port->tx_remaining);
1037 	port->tx_dma_addr = 0;
1038 	port->tx_remaining = 0;
1039 
1040 	if (!kfifo_is_empty(&tport->xmit_fifo))
1041 		qcom_geni_serial_start_tx_dma(uport);
1042 
1043 	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
1044 		uart_write_wakeup(uport);
1045 }
1046 
1047 static irqreturn_t qcom_geni_serial_isr(int isr, void *dev)
1048 {
1049 	u32 m_irq_en;
1050 	u32 m_irq_status;
1051 	u32 s_irq_status;
1052 	u32 geni_status;
1053 	u32 dma;
1054 	u32 dma_tx_status;
1055 	u32 dma_rx_status;
1056 	struct uart_port *uport = dev;
1057 	bool drop_rx = false;
1058 	struct tty_port *tport = &uport->state->port;
1059 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1060 
1061 	if (uport->suspended)
1062 		return IRQ_NONE;
1063 
1064 	uart_port_lock(uport);
1065 
1066 	m_irq_status = readl(uport->membase + SE_GENI_M_IRQ_STATUS);
1067 	s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
1068 	dma_tx_status = readl(uport->membase + SE_DMA_TX_IRQ_STAT);
1069 	dma_rx_status = readl(uport->membase + SE_DMA_RX_IRQ_STAT);
1070 	geni_status = readl(uport->membase + SE_GENI_STATUS);
1071 	dma = readl(uport->membase + SE_GENI_DMA_MODE_EN);
1072 	m_irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
1073 	writel(m_irq_status, uport->membase + SE_GENI_M_IRQ_CLEAR);
1074 	writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
1075 	writel(dma_tx_status, uport->membase + SE_DMA_TX_IRQ_CLR);
1076 	writel(dma_rx_status, uport->membase + SE_DMA_RX_IRQ_CLR);
1077 
1078 	if (WARN_ON(m_irq_status & M_ILLEGAL_CMD_EN))
1079 		goto out_unlock;
1080 
1081 	if (s_irq_status & S_RX_FIFO_WR_ERR_EN) {
1082 		uport->icount.overrun++;
1083 		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
1084 	}
1085 
1086 	if (s_irq_status & (S_GP_IRQ_0_EN | S_GP_IRQ_1_EN)) {
1087 		if (s_irq_status & S_GP_IRQ_0_EN)
1088 			uport->icount.parity++;
1089 		drop_rx = true;
1090 	} else if (s_irq_status & (S_GP_IRQ_2_EN | S_GP_IRQ_3_EN)) {
1091 		uport->icount.brk++;
1092 		port->brk = true;
1093 	}
1094 
1095 	if (dma) {
1096 		if (dma_tx_status & TX_DMA_DONE) {
1097 			qcom_geni_serial_handle_tx_dma(uport);
1098 			qcom_geni_set_rs485_mode(uport, SER_RS485_RTS_AFTER_SEND);
1099 	}
1100 
1101 		if (dma_rx_status) {
1102 			if (dma_rx_status & RX_RESET_DONE)
1103 				goto out_unlock;
1104 
1105 			if (dma_rx_status & RX_DMA_PARITY_ERR) {
1106 				uport->icount.parity++;
1107 				drop_rx = true;
1108 			}
1109 
1110 			if (dma_rx_status & RX_DMA_BREAK)
1111 				uport->icount.brk++;
1112 
1113 			if (dma_rx_status & (RX_DMA_DONE | RX_EOT))
1114 				qcom_geni_serial_handle_rx_dma(uport, drop_rx);
1115 		}
1116 	} else {
1117 		if (m_irq_status & m_irq_en &
1118 		    (M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN))
1119 			qcom_geni_serial_handle_tx_fifo(uport,
1120 					m_irq_status & M_CMD_DONE_EN,
1121 					geni_status & M_GENI_CMD_ACTIVE);
1122 
1123 		if (s_irq_status & (S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN))
1124 			qcom_geni_serial_handle_rx_fifo(uport, drop_rx);
1125 	}
1126 
1127 out_unlock:
1128 	uart_unlock_and_check_sysrq(uport);
1129 
1130 	return IRQ_HANDLED;
1131 }
1132 
1133 static int setup_fifos(struct qcom_geni_serial_port *port)
1134 {
1135 	struct uart_port *uport;
1136 	u32 old_rx_fifo_depth = port->rx_fifo_depth;
1137 
1138 	uport = &port->uport;
1139 	port->tx_fifo_depth = geni_se_get_tx_fifo_depth(&port->se);
1140 	port->tx_fifo_width = geni_se_get_tx_fifo_width(&port->se);
1141 	port->rx_fifo_depth = geni_se_get_rx_fifo_depth(&port->se);
1142 	uport->fifosize =
1143 		(port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE;
1144 
1145 	if (port->rx_buf && (old_rx_fifo_depth != port->rx_fifo_depth) && port->rx_fifo_depth) {
1146 		/*
1147 		 * Use krealloc rather than krealloc_array because rx_buf is
1148 		 * accessed as 1 byte entries as well as 4 byte entries so it's
1149 		 * not necessarily an array.
1150 		 */
1151 		port->rx_buf = devm_krealloc(uport->dev, port->rx_buf,
1152 					     port->rx_fifo_depth * sizeof(u32),
1153 					     GFP_KERNEL);
1154 		if (!port->rx_buf)
1155 			return -ENOMEM;
1156 	}
1157 
1158 	return 0;
1159 }
1160 
1161 
1162 static void qcom_geni_serial_shutdown(struct uart_port *uport)
1163 {
1164 	disable_irq(uport->irq);
1165 
1166 	uart_port_lock_irq(uport);
1167 	qcom_geni_serial_stop_tx(uport);
1168 	qcom_geni_serial_stop_rx(uport);
1169 
1170 	qcom_geni_serial_cancel_tx_cmd(uport);
1171 	uart_port_unlock_irq(uport);
1172 }
1173 
1174 static void qcom_geni_serial_flush_buffer(struct uart_port *uport)
1175 {
1176 	qcom_geni_serial_cancel_tx_cmd(uport);
1177 }
1178 
1179 static int qcom_geni_serial_port_setup(struct uart_port *uport)
1180 {
1181 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1182 	u32 rxstale = DEFAULT_BITS_PER_CHAR * STALE_TIMEOUT;
1183 	u32 proto;
1184 	u32 pin_swap;
1185 	int ret;
1186 
1187 	proto = geni_se_read_proto(&port->se);
1188 	if (proto == GENI_SE_INVALID_PROTO) {
1189 		ret = geni_load_se_firmware(&port->se, GENI_SE_UART);
1190 		if (ret) {
1191 			dev_err(uport->dev, "UART firmware load failed ret: %d\n", ret);
1192 			return ret;
1193 		}
1194 	} else if (proto != GENI_SE_UART) {
1195 		dev_err(uport->dev, "Invalid FW loaded, proto: %d\n", proto);
1196 		return -ENXIO;
1197 	}
1198 
1199 	qcom_geni_serial_stop_rx(uport);
1200 
1201 	ret = setup_fifos(port);
1202 	if (ret)
1203 		return ret;
1204 
1205 	writel(rxstale, uport->membase + SE_UART_RX_STALE_CNT);
1206 
1207 	pin_swap = readl(uport->membase + SE_UART_IO_MACRO_CTRL);
1208 	if (port->rx_tx_swap) {
1209 		pin_swap &= ~DEFAULT_IO_MACRO_IO2_IO3_MASK;
1210 		pin_swap |= IO_MACRO_IO2_IO3_SWAP;
1211 	}
1212 	if (port->cts_rts_swap) {
1213 		pin_swap &= ~DEFAULT_IO_MACRO_IO0_IO1_MASK;
1214 		pin_swap |= IO_MACRO_IO0_SEL;
1215 	}
1216 	/* Configure this register if RX-TX, CTS-RTS pins are swapped */
1217 	if (port->rx_tx_swap || port->cts_rts_swap)
1218 		writel(pin_swap, uport->membase + SE_UART_IO_MACRO_CTRL);
1219 
1220 	/*
1221 	 * Make an unconditional cancel on the main sequencer to reset
1222 	 * it else we could end up in data loss scenarios.
1223 	 */
1224 	if (uart_console(uport))
1225 		qcom_geni_serial_poll_tx_done(uport);
1226 	geni_se_config_packing(&port->se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
1227 			       false, true, true);
1228 	geni_se_init(&port->se, UART_RX_WM, port->rx_fifo_depth - 2);
1229 	geni_se_select_mode(&port->se, port->dev_data->mode);
1230 	port->setup = true;
1231 
1232 	return 0;
1233 }
1234 
1235 static int qcom_geni_serial_startup(struct uart_port *uport)
1236 {
1237 	int ret;
1238 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1239 
1240 	if (!port->setup) {
1241 		ret = qcom_geni_serial_port_setup(uport);
1242 		if (ret)
1243 			return ret;
1244 	}
1245 
1246 	uart_port_lock_irq(uport);
1247 	qcom_geni_serial_start_rx(uport);
1248 	uart_port_unlock_irq(uport);
1249 
1250 	enable_irq(uport->irq);
1251 
1252 	return 0;
1253 }
1254 
1255 static int geni_serial_set_rate(struct uart_port *uport, unsigned int baud)
1256 {
1257 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1258 	unsigned long clk_rate;
1259 	unsigned int avg_bw_core, clk_idx;
1260 	unsigned int clk_div;
1261 	u32 ver, sampling_rate;
1262 	u32 ser_clk_cfg;
1263 	int ret;
1264 
1265 	sampling_rate = UART_OVERSAMPLING;
1266 	/* Sampling rate is halved for IP versions >= 2.5 */
1267 	ver = geni_se_get_qup_hw_version(&port->se);
1268 	if (ver >= QUP_SE_VERSION_2_5)
1269 		sampling_rate /= 2;
1270 
1271 	ret = geni_se_clk_freq_match(&port->se, baud * sampling_rate, &clk_idx, &clk_rate, false);
1272 	if (ret) {
1273 		dev_err(port->se.dev, "Failed to find src clk for baud rate: %d ret: %d\n",
1274 			baud, ret);
1275 		return ret;
1276 	}
1277 
1278 	clk_div = DIV_ROUND_UP(clk_rate, baud * sampling_rate);
1279 	/* Check if calculated divider exceeds maximum allowed value */
1280 	if (clk_div > (CLK_DIV_MSK >> CLK_DIV_SHFT)) {
1281 		dev_err(port->se.dev, "Calculated clock divider %u exceeds maximum\n", clk_div);
1282 		return -EINVAL;
1283 	}
1284 
1285 	dev_dbg(port->se.dev, "desired_rate = %u, clk_rate = %lu, clk_div = %u, clk_idx = %u\n",
1286 		baud * sampling_rate, clk_rate, clk_div, clk_idx);
1287 
1288 	uport->uartclk = clk_rate;
1289 	port->clk_rate = clk_rate;
1290 	dev_pm_opp_set_rate(uport->dev, clk_rate);
1291 	ser_clk_cfg = SER_CLK_EN;
1292 	ser_clk_cfg |= clk_div << CLK_DIV_SHFT;
1293 
1294 	/*
1295 	 * Bump up BW vote on CPU and CORE path as driver supports FIFO mode
1296 	 * only.
1297 	 */
1298 	avg_bw_core = (baud > 115200) ? Bps_to_icc(CORE_2X_50_MHZ)
1299 						: GENI_DEFAULT_BW;
1300 	port->se.icc_paths[GENI_TO_CORE].avg_bw = avg_bw_core;
1301 	port->se.icc_paths[CPU_TO_GENI].avg_bw = Bps_to_icc(baud);
1302 	geni_icc_set_bw(&port->se);
1303 
1304 	writel(ser_clk_cfg, uport->membase + GENI_SER_M_CLK_CFG);
1305 	writel(ser_clk_cfg, uport->membase + GENI_SER_S_CLK_CFG);
1306 	/* Configure clock selection register with the selected clock index */
1307 	writel(clk_idx & CLK_SEL_MSK, uport->membase + SE_GENI_CLK_SEL);
1308 	return 0;
1309 }
1310 
1311 static int geni_serial_set_level(struct uart_port *uport, unsigned int baud)
1312 {
1313 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1314 	struct device *perf_dev = port->pd_list->pd_devs[DOMAIN_IDX_PERF];
1315 
1316 	/*
1317 	 * The performance protocol sets UART communication
1318 	 * speeds by selecting different performance levels
1319 	 * through the OPP framework.
1320 	 *
1321 	 * Supported perf levels for baudrates in firmware are below
1322 	 * +---------------------+--------------------+
1323 	 * |  Perf level value   |  Baudrate values   |
1324 	 * +---------------------+--------------------+
1325 	 * |      300            |      300           |
1326 	 * |      1200           |      1200          |
1327 	 * |      2400           |      2400          |
1328 	 * |      4800           |      4800          |
1329 	 * |      9600           |      9600          |
1330 	 * |      19200          |      19200         |
1331 	 * |      38400          |      38400         |
1332 	 * |      57600          |      57600         |
1333 	 * |      115200         |      115200        |
1334 	 * |      230400         |      230400        |
1335 	 * |      460800         |      460800        |
1336 	 * |      921600         |      921600        |
1337 	 * |      2000000        |      2000000       |
1338 	 * |      3000000        |      3000000       |
1339 	 * |      3200000        |      3200000       |
1340 	 * |      4000000        |      4000000       |
1341 	 * +---------------------+--------------------+
1342 	 */
1343 
1344 	return dev_pm_opp_set_level(perf_dev, baud);
1345 }
1346 
1347 static void qcom_geni_serial_set_termios(struct uart_port *uport,
1348 					 struct ktermios *termios,
1349 					 const struct ktermios *old)
1350 {
1351 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1352 	unsigned int baud;
1353 	unsigned long timeout;
1354 	u32 bits_per_char;
1355 	u32 tx_trans_cfg;
1356 	u32 tx_parity_cfg;
1357 	u32 rx_trans_cfg;
1358 	u32 rx_parity_cfg;
1359 	u32 stop_bit_len;
1360 	int ret = 0;
1361 
1362 	/* baud rate */
1363 	baud = uart_get_baud_rate(uport, termios, old, 300, 8000000);
1364 
1365 	ret = port->dev_data->set_rate(uport, baud);
1366 	if (ret)
1367 		return;
1368 
1369 	/* parity */
1370 	tx_trans_cfg = readl(uport->membase + SE_UART_TX_TRANS_CFG);
1371 	tx_parity_cfg = readl(uport->membase + SE_UART_TX_PARITY_CFG);
1372 	rx_trans_cfg = readl(uport->membase + SE_UART_RX_TRANS_CFG);
1373 	rx_parity_cfg = readl(uport->membase + SE_UART_RX_PARITY_CFG);
1374 	if (termios->c_cflag & PARENB) {
1375 		tx_trans_cfg |= UART_TX_PAR_EN;
1376 		rx_trans_cfg |= UART_RX_PAR_EN;
1377 		tx_parity_cfg |= PAR_CALC_EN;
1378 		rx_parity_cfg |= PAR_CALC_EN;
1379 		if (termios->c_cflag & PARODD) {
1380 			tx_parity_cfg |= PAR_ODD;
1381 			rx_parity_cfg |= PAR_ODD;
1382 		} else if (termios->c_cflag & CMSPAR) {
1383 			tx_parity_cfg |= PAR_SPACE;
1384 			rx_parity_cfg |= PAR_SPACE;
1385 		} else {
1386 			tx_parity_cfg |= PAR_EVEN;
1387 			rx_parity_cfg |= PAR_EVEN;
1388 		}
1389 	} else {
1390 		tx_trans_cfg &= ~UART_TX_PAR_EN;
1391 		rx_trans_cfg &= ~UART_RX_PAR_EN;
1392 		tx_parity_cfg &= ~PAR_CALC_EN;
1393 		rx_parity_cfg &= ~PAR_CALC_EN;
1394 	}
1395 
1396 	/* bits per char */
1397 	bits_per_char = tty_get_char_size(termios->c_cflag);
1398 
1399 	/* stop bits */
1400 	if (termios->c_cflag & CSTOPB)
1401 		stop_bit_len = TX_STOP_BIT_LEN_2;
1402 	else
1403 		stop_bit_len = TX_STOP_BIT_LEN_1;
1404 
1405 	/* Configure flow control based on CRTSCTS flag.
1406 	 * When CRTSCTS is set, use HW/auto flow control mode, where HW
1407 	 * controls the RTS/CTS pin based FIFO state.
1408 	 * When CRTSCTS is clear, the CTS pin value is ignored for TX
1409 	 * path and RTS pin can be set/cleared using registers, for RX
1410 	 * path.
1411 	 */
1412 
1413 	if (termios->c_cflag & CRTSCTS) {
1414 		tx_trans_cfg &= ~UART_CTS_MASK;
1415 		port->manual_flow = false;
1416 	} else {
1417 		tx_trans_cfg |= UART_CTS_MASK;
1418 		port->manual_flow = true;
1419 	}
1420 
1421 	if (baud) {
1422 		uart_update_timeout(uport, termios->c_cflag, baud);
1423 
1424 		/*
1425 		 * Make sure that qcom_geni_serial_poll_bitfield() waits for
1426 		 * the FIFO, two-word intermediate transfer register and shift
1427 		 * register to clear.
1428 		 *
1429 		 * Note that uart_fifo_timeout() also adds a 20 ms margin.
1430 		 */
1431 		timeout = jiffies_to_usecs(uart_fifo_timeout(uport));
1432 		timeout += 3 * timeout / port->tx_fifo_depth;
1433 		WRITE_ONCE(port->poll_timeout_us, timeout);
1434 	}
1435 
1436 	if (!uart_console(uport))
1437 		writel(port->loopback,
1438 				uport->membase + SE_UART_LOOPBACK_CFG);
1439 	writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1440 	writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1441 	writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1442 	writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1443 	writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1444 	writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1445 	writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1446 }
1447 
1448 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
1449 static int qcom_geni_console_setup(struct console *co, char *options)
1450 {
1451 	struct uart_port *uport;
1452 	struct qcom_geni_serial_port *port;
1453 	int baud = 115200;
1454 	int bits = 8;
1455 	int parity = 'n';
1456 	int flow = 'n';
1457 	int ret;
1458 
1459 	if (co->index >= GENI_UART_CONS_PORTS  || co->index < 0)
1460 		return -ENXIO;
1461 
1462 	port = get_port_from_line(co->index, true, NULL);
1463 	if (IS_ERR(port)) {
1464 		pr_err("Invalid line %d\n", co->index);
1465 		return PTR_ERR(port);
1466 	}
1467 
1468 	uport = &port->uport;
1469 
1470 	if (unlikely(!uport->membase))
1471 		return -ENXIO;
1472 
1473 	if (!port->setup) {
1474 		ret = qcom_geni_serial_port_setup(uport);
1475 		if (ret)
1476 			return ret;
1477 	}
1478 
1479 	if (options)
1480 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1481 
1482 	return uart_set_options(uport, co, baud, parity, bits, flow);
1483 }
1484 
1485 static void qcom_geni_serial_earlycon_write(struct console *con,
1486 					const char *s, unsigned int n)
1487 {
1488 	struct earlycon_device *dev = con->data;
1489 
1490 	__qcom_geni_serial_console_write(&dev->port, s, n);
1491 }
1492 
1493 #ifdef CONFIG_CONSOLE_POLL
1494 static int qcom_geni_serial_earlycon_read(struct console *con,
1495 					  char *s, unsigned int n)
1496 {
1497 	struct earlycon_device *dev = con->data;
1498 	struct uart_port *uport = &dev->port;
1499 	int num_read = 0;
1500 	int ch;
1501 
1502 	while (num_read < n) {
1503 		ch = qcom_geni_serial_get_char(uport);
1504 		if (ch == NO_POLL_CHAR)
1505 			break;
1506 		s[num_read++] = ch;
1507 	}
1508 
1509 	return num_read;
1510 }
1511 
1512 static void __init qcom_geni_serial_enable_early_read(struct geni_se *se,
1513 						      struct console *con)
1514 {
1515 	geni_se_setup_s_cmd(se, UART_START_READ, 0);
1516 	con->read = qcom_geni_serial_earlycon_read;
1517 }
1518 #else
1519 static inline void qcom_geni_serial_enable_early_read(struct geni_se *se,
1520 						      struct console *con) { }
1521 #endif
1522 
1523 static struct qcom_geni_private_data earlycon_private_data;
1524 
1525 static int __init qcom_geni_serial_earlycon_setup(struct earlycon_device *dev,
1526 								const char *opt)
1527 {
1528 	struct uart_port *uport = &dev->port;
1529 	u32 tx_trans_cfg;
1530 	u32 tx_parity_cfg = 0;	/* Disable Tx Parity */
1531 	u32 rx_trans_cfg = 0;
1532 	u32 rx_parity_cfg = 0;	/* Disable Rx Parity */
1533 	u32 stop_bit_len = 0;	/* Default stop bit length - 1 bit */
1534 	u32 bits_per_char;
1535 	struct geni_se se;
1536 
1537 	if (!uport->membase)
1538 		return -EINVAL;
1539 
1540 	uport->private_data = &earlycon_private_data;
1541 
1542 	memset(&se, 0, sizeof(se));
1543 	se.base = uport->membase;
1544 	if (geni_se_read_proto(&se) != GENI_SE_UART)
1545 		return -ENXIO;
1546 	/*
1547 	 * Ignore Flow control.
1548 	 * n = 8.
1549 	 */
1550 	tx_trans_cfg = UART_CTS_MASK;
1551 	bits_per_char = BITS_PER_BYTE;
1552 
1553 	/*
1554 	 * Make an unconditional cancel on the main sequencer to reset
1555 	 * it else we could end up in data loss scenarios.
1556 	 */
1557 	qcom_geni_serial_poll_tx_done(uport);
1558 	qcom_geni_serial_abort_rx(uport);
1559 	geni_se_config_packing(&se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
1560 			       false, true, true);
1561 	geni_se_init(&se, DEF_FIFO_DEPTH_WORDS / 2, DEF_FIFO_DEPTH_WORDS - 2);
1562 	geni_se_select_mode(&se, GENI_SE_FIFO);
1563 
1564 	writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1565 	writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1566 	writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1567 	writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1568 	writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1569 	writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1570 	writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1571 
1572 	dev->con->write = qcom_geni_serial_earlycon_write;
1573 	dev->con->setup = NULL;
1574 	qcom_geni_serial_enable_early_read(&se, dev->con);
1575 
1576 	return 0;
1577 }
1578 OF_EARLYCON_DECLARE(qcom_geni, "qcom,geni-debug-uart",
1579 				qcom_geni_serial_earlycon_setup);
1580 
1581 static int __init console_register(struct uart_driver *drv)
1582 {
1583 	return uart_register_driver(drv);
1584 }
1585 
1586 static void console_unregister(struct uart_driver *drv)
1587 {
1588 	uart_unregister_driver(drv);
1589 }
1590 
1591 static struct console cons_ops = {
1592 	.name = "ttyMSM",
1593 	.write = qcom_geni_serial_console_write,
1594 	.device = uart_console_device,
1595 	.setup = qcom_geni_console_setup,
1596 	.flags = CON_PRINTBUFFER,
1597 	.index = -1,
1598 	.data = &qcom_geni_console_driver,
1599 };
1600 
1601 static struct uart_driver qcom_geni_console_driver = {
1602 	.owner = THIS_MODULE,
1603 	.driver_name = "qcom_geni_console",
1604 	.dev_name = "ttyMSM",
1605 	.nr =  GENI_UART_CONS_PORTS,
1606 	.cons = &cons_ops,
1607 };
1608 #else
1609 static int console_register(struct uart_driver *drv)
1610 {
1611 	return 0;
1612 }
1613 
1614 static void console_unregister(struct uart_driver *drv)
1615 {
1616 }
1617 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
1618 
1619 static struct uart_driver qcom_geni_uart_driver = {
1620 	.owner = THIS_MODULE,
1621 	.driver_name = "qcom_geni_uart",
1622 	.dev_name = "ttyHS",
1623 	.nr = CONFIG_SERIAL_QCOM_GENI_UART_PORTS,
1624 };
1625 
1626 static int geni_serial_resources_on(struct uart_port *uport)
1627 {
1628 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1629 	int ret;
1630 
1631 	ret = geni_icc_enable(&port->se);
1632 	if (ret)
1633 		return ret;
1634 
1635 	ret = geni_se_resources_on(&port->se);
1636 	if (ret) {
1637 		geni_icc_disable(&port->se);
1638 		return ret;
1639 	}
1640 
1641 	if (port->clk_rate)
1642 		dev_pm_opp_set_rate(uport->dev, port->clk_rate);
1643 
1644 	return 0;
1645 }
1646 
1647 static int geni_serial_resources_off(struct uart_port *uport)
1648 {
1649 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1650 	int ret;
1651 
1652 	dev_pm_opp_set_rate(uport->dev, 0);
1653 	ret = geni_se_resources_off(&port->se);
1654 	if (ret)
1655 		return ret;
1656 
1657 	geni_icc_disable(&port->se);
1658 
1659 	return 0;
1660 }
1661 
1662 static int geni_serial_resource_state(struct uart_port *uport, bool power_on)
1663 {
1664 	return power_on ? geni_serial_resources_on(uport) : geni_serial_resources_off(uport);
1665 }
1666 
1667 static int geni_serial_pwr_init(struct uart_port *uport)
1668 {
1669 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1670 	int ret;
1671 
1672 	ret = dev_pm_domain_attach_list(port->se.dev,
1673 					&port->dev_data->pd_data, &port->pd_list);
1674 	if (ret <= 0)
1675 		return -EINVAL;
1676 
1677 	return 0;
1678 }
1679 
1680 static int geni_serial_resource_init(struct uart_port *uport)
1681 {
1682 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1683 	int ret;
1684 
1685 	port->se.clk = devm_clk_get(port->se.dev, "se");
1686 	if (IS_ERR(port->se.clk)) {
1687 		ret = PTR_ERR(port->se.clk);
1688 		dev_err(port->se.dev, "Err getting SE Core clk %d\n", ret);
1689 		return ret;
1690 	}
1691 
1692 	ret = geni_icc_get(&port->se, NULL);
1693 	if (ret)
1694 		return ret;
1695 
1696 	port->se.icc_paths[GENI_TO_CORE].avg_bw = GENI_DEFAULT_BW;
1697 	port->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
1698 
1699 	/* Set BW for register access */
1700 	ret = geni_icc_set_bw(&port->se);
1701 	if (ret)
1702 		return ret;
1703 
1704 	ret = devm_pm_opp_set_clkname(port->se.dev, "se");
1705 	if (ret)
1706 		return ret;
1707 
1708 	/* OPP table is optional */
1709 	ret = devm_pm_opp_of_add_table(port->se.dev);
1710 	if (ret && ret != -ENODEV) {
1711 		dev_err(port->se.dev, "invalid OPP table in device tree\n");
1712 		return ret;
1713 	}
1714 
1715 	return 0;
1716 }
1717 
1718 static void qcom_geni_serial_pm(struct uart_port *uport,
1719 		unsigned int new_state, unsigned int old_state)
1720 {
1721 
1722 	/* If we've never been called, treat it as off */
1723 	if (old_state == UART_PM_STATE_UNDEFINED)
1724 		old_state = UART_PM_STATE_OFF;
1725 
1726 	if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF)
1727 		pm_runtime_resume_and_get(uport->dev);
1728 	else if (new_state == UART_PM_STATE_OFF &&
1729 		 old_state == UART_PM_STATE_ON)
1730 		pm_runtime_put_sync(uport->dev);
1731 
1732 }
1733 
1734 /**
1735  * qcom_geni_rs485_config - Configure RS485 settings for the UART port
1736  * @uport: Pointer to the UART port structure
1737  * @termios: Pointer to the termios structure
1738  * @rs485: Pointer to the RS485 configuration structure
1739  * This function configures the RTS (Request to Send) pin behavior for RS485 mode.
1740  * When RS485 mode is enabled, the RTS pin is kept in default ACTIVE HIGH state.
1741  * Return: Always returns 0.
1742  */
1743 
1744 static int qcom_geni_rs485_config(struct uart_port *uport,
1745 				  struct ktermios *termios, struct serial_rs485 *rs485)
1746 {
1747 	qcom_geni_set_rs485_mode(uport, SER_RS485_ENABLED);
1748 
1749 	return 0;
1750 }
1751 
1752 static const struct uart_ops qcom_geni_console_pops = {
1753 	.tx_empty = qcom_geni_serial_tx_empty,
1754 	.stop_tx = qcom_geni_serial_stop_tx_fifo,
1755 	.start_tx = qcom_geni_serial_start_tx_fifo,
1756 	.stop_rx = qcom_geni_serial_stop_rx_fifo,
1757 	.start_rx = qcom_geni_serial_start_rx_fifo,
1758 	.set_termios = qcom_geni_serial_set_termios,
1759 	.startup = qcom_geni_serial_startup,
1760 	.request_port = qcom_geni_serial_request_port,
1761 	.config_port = qcom_geni_serial_config_port,
1762 	.shutdown = qcom_geni_serial_shutdown,
1763 	.flush_buffer = qcom_geni_serial_flush_buffer,
1764 	.type = qcom_geni_serial_get_type,
1765 	.set_mctrl = qcom_geni_serial_set_mctrl,
1766 	.get_mctrl = qcom_geni_serial_get_mctrl,
1767 #ifdef CONFIG_CONSOLE_POLL
1768 	.poll_get_char	= qcom_geni_serial_get_char,
1769 	.poll_put_char	= qcom_geni_serial_poll_put_char,
1770 	.poll_init = qcom_geni_serial_poll_init,
1771 #endif
1772 	.pm = qcom_geni_serial_pm,
1773 };
1774 
1775 static const struct uart_ops qcom_geni_uart_pops = {
1776 	.tx_empty = qcom_geni_serial_tx_empty,
1777 	.stop_tx = qcom_geni_serial_stop_tx_dma,
1778 	.start_tx = qcom_geni_serial_start_tx_dma,
1779 	.start_rx = qcom_geni_serial_start_rx_dma,
1780 	.stop_rx = qcom_geni_serial_stop_rx_dma,
1781 	.set_termios = qcom_geni_serial_set_termios,
1782 	.startup = qcom_geni_serial_startup,
1783 	.request_port = qcom_geni_serial_request_port,
1784 	.config_port = qcom_geni_serial_config_port,
1785 	.shutdown = qcom_geni_serial_shutdown,
1786 	.type = qcom_geni_serial_get_type,
1787 	.set_mctrl = qcom_geni_serial_set_mctrl,
1788 	.get_mctrl = qcom_geni_serial_get_mctrl,
1789 	.pm = qcom_geni_serial_pm,
1790 };
1791 
1792 static int qcom_geni_serial_probe(struct platform_device *pdev)
1793 {
1794 	int ret = 0;
1795 	int line;
1796 	struct qcom_geni_serial_port *port;
1797 	struct uart_port *uport;
1798 	struct resource *res;
1799 	int irq;
1800 	struct uart_driver *drv;
1801 	const struct qcom_geni_device_data *data;
1802 
1803 	data = of_device_get_match_data(&pdev->dev);
1804 	if (!data)
1805 		return -EINVAL;
1806 
1807 	if (data->console) {
1808 		drv = &qcom_geni_console_driver;
1809 		line = of_alias_get_id(pdev->dev.of_node, "serial");
1810 	} else {
1811 		drv = &qcom_geni_uart_driver;
1812 		line = of_alias_get_id(pdev->dev.of_node, "serial");
1813 		if (line == -ENODEV) /* compat with non-standard aliases */
1814 			line = of_alias_get_id(pdev->dev.of_node, "hsuart");
1815 	}
1816 
1817 	port = get_port_from_line(line, data->console, &pdev->dev);
1818 	if (IS_ERR(port)) {
1819 		dev_err(&pdev->dev, "Invalid line %d\n", line);
1820 		return PTR_ERR(port);
1821 	}
1822 
1823 	uport = &port->uport;
1824 	/* Don't allow 2 drivers to access the same port */
1825 	if (uport->private_data)
1826 		return -ENODEV;
1827 
1828 	uport->dev = &pdev->dev;
1829 	port->dev_data = data;
1830 	port->se.dev = &pdev->dev;
1831 	port->se.wrapper = dev_get_drvdata(pdev->dev.parent);
1832 
1833 	ret = port->dev_data->resources_init(uport);
1834 	if (ret)
1835 		return ret;
1836 
1837 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1838 	if (!res) {
1839 		ret = -EINVAL;
1840 		goto error;
1841 	}
1842 
1843 	uport->mapbase = res->start;
1844 
1845 	uport->rs485_config = qcom_geni_rs485_config;
1846 	uport->rs485_supported = qcom_geni_rs485_supported;
1847 	port->tx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1848 	port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1849 	port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;
1850 
1851 	if (!data->console) {
1852 		port->rx_buf = devm_kzalloc(uport->dev,
1853 					    DMA_RX_BUF_SIZE, GFP_KERNEL);
1854 		if (!port->rx_buf) {
1855 			ret = -ENOMEM;
1856 			goto error;
1857 		}
1858 	}
1859 
1860 	port->name = devm_kasprintf(uport->dev, GFP_KERNEL,
1861 			"qcom_geni_serial_%s%d",
1862 			uart_console(uport) ? "console" : "uart", uport->line);
1863 	if (!port->name) {
1864 		ret = -ENOMEM;
1865 		goto error;
1866 	}
1867 
1868 	irq = platform_get_irq(pdev, 0);
1869 	if (irq < 0) {
1870 		ret = irq;
1871 		goto error;
1872 	}
1873 
1874 	uport->irq = irq;
1875 	uport->has_sysrq = IS_ENABLED(CONFIG_SERIAL_QCOM_GENI_CONSOLE);
1876 
1877 	if (!data->console)
1878 		port->wakeup_irq = platform_get_irq_optional(pdev, 1);
1879 
1880 	if (of_property_read_bool(pdev->dev.of_node, "rx-tx-swap"))
1881 		port->rx_tx_swap = true;
1882 
1883 	if (of_property_read_bool(pdev->dev.of_node, "cts-rts-swap"))
1884 		port->cts_rts_swap = true;
1885 
1886 	port->private_data.drv = drv;
1887 	uport->private_data = &port->private_data;
1888 	platform_set_drvdata(pdev, port);
1889 
1890 	irq_set_status_flags(uport->irq, IRQ_NOAUTOEN);
1891 	ret = devm_request_irq(uport->dev, uport->irq, qcom_geni_serial_isr,
1892 			IRQF_TRIGGER_HIGH, port->name, uport);
1893 	if (ret) {
1894 		dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret);
1895 		goto error;
1896 	}
1897 
1898 	ret = uart_get_rs485_mode(uport);
1899 	if (ret)
1900 		goto error;
1901 
1902 	if (port->wakeup_irq > 0) {
1903 		device_init_wakeup(&pdev->dev, true);
1904 		ret = dev_pm_set_dedicated_wake_irq(&pdev->dev,
1905 						port->wakeup_irq);
1906 		if (ret) {
1907 			device_init_wakeup(&pdev->dev, false);
1908 			ida_free(&port_ida, uport->line);
1909 			goto error;
1910 		}
1911 	}
1912 
1913 	devm_pm_runtime_enable(port->se.dev);
1914 
1915 	ret = uart_add_one_port(drv, uport);
1916 	if (ret)
1917 		goto error;
1918 
1919 	return 0;
1920 
1921 error:
1922 	dev_pm_domain_detach_list(port->pd_list);
1923 	return ret;
1924 }
1925 
1926 static void qcom_geni_serial_remove(struct platform_device *pdev)
1927 {
1928 	struct qcom_geni_serial_port *port = platform_get_drvdata(pdev);
1929 	struct uart_port *uport = &port->uport;
1930 	struct uart_driver *drv = port->private_data.drv;
1931 
1932 	dev_pm_clear_wake_irq(&pdev->dev);
1933 	device_init_wakeup(&pdev->dev, false);
1934 	ida_free(&port_ida, uport->line);
1935 	uart_remove_one_port(drv, &port->uport);
1936 	dev_pm_domain_detach_list(port->pd_list);
1937 }
1938 
1939 static int __maybe_unused qcom_geni_serial_runtime_suspend(struct device *dev)
1940 {
1941 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1942 	struct uart_port *uport = &port->uport;
1943 	int ret = 0;
1944 
1945 	if (port->dev_data->power_state)
1946 		ret = port->dev_data->power_state(uport, false);
1947 
1948 	return ret;
1949 }
1950 
1951 static int __maybe_unused qcom_geni_serial_runtime_resume(struct device *dev)
1952 {
1953 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1954 	struct uart_port *uport = &port->uport;
1955 	int ret = 0;
1956 
1957 	if (port->dev_data->power_state)
1958 		ret = port->dev_data->power_state(uport, true);
1959 
1960 	return ret;
1961 }
1962 
1963 static int qcom_geni_serial_suspend(struct device *dev)
1964 {
1965 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1966 	struct uart_port *uport = &port->uport;
1967 	struct qcom_geni_private_data *private_data = uport->private_data;
1968 
1969 	/*
1970 	 * This is done so we can hit the lowest possible state in suspend
1971 	 * even with no_console_suspend
1972 	 */
1973 	if (uart_console(uport)) {
1974 		geni_icc_set_tag(&port->se, QCOM_ICC_TAG_ACTIVE_ONLY);
1975 		geni_icc_set_bw(&port->se);
1976 	}
1977 	return uart_suspend_port(private_data->drv, uport);
1978 }
1979 
1980 static int qcom_geni_serial_resume(struct device *dev)
1981 {
1982 	int ret;
1983 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1984 	struct uart_port *uport = &port->uport;
1985 	struct qcom_geni_private_data *private_data = uport->private_data;
1986 
1987 	ret = uart_resume_port(private_data->drv, uport);
1988 	if (uart_console(uport)) {
1989 		geni_icc_set_tag(&port->se, QCOM_ICC_TAG_ALWAYS);
1990 		geni_icc_set_bw(&port->se);
1991 	}
1992 	return ret;
1993 }
1994 
1995 static const struct qcom_geni_device_data qcom_geni_console_data = {
1996 	.console = true,
1997 	.mode = GENI_SE_FIFO,
1998 	.resources_init = geni_serial_resource_init,
1999 	.set_rate = geni_serial_set_rate,
2000 	.power_state = geni_serial_resource_state,
2001 };
2002 
2003 static const struct qcom_geni_device_data qcom_geni_uart_data = {
2004 	.console = false,
2005 	.mode = GENI_SE_DMA,
2006 	.resources_init = geni_serial_resource_init,
2007 	.set_rate = geni_serial_set_rate,
2008 	.power_state = geni_serial_resource_state,
2009 };
2010 
2011 static const struct qcom_geni_device_data sa8255p_qcom_geni_console_data = {
2012 	.console = true,
2013 	.mode = GENI_SE_FIFO,
2014 	.pd_data = {
2015 		.pd_flags = PD_FLAG_DEV_LINK_ON,
2016 		.pd_names = (const char*[]) { "power", "perf" },
2017 		.num_pd_names = 2,
2018 	},
2019 	.resources_init = geni_serial_pwr_init,
2020 	.set_rate = geni_serial_set_level,
2021 };
2022 
2023 static const struct qcom_geni_device_data sa8255p_qcom_geni_uart_data = {
2024 	.console = false,
2025 	.mode = GENI_SE_DMA,
2026 	.pd_data = {
2027 		.pd_flags = PD_FLAG_DEV_LINK_ON,
2028 		.pd_names = (const char*[]) { "power", "perf" },
2029 		.num_pd_names = 2,
2030 	},
2031 	.resources_init = geni_serial_pwr_init,
2032 	.set_rate = geni_serial_set_level,
2033 };
2034 
2035 static const struct dev_pm_ops qcom_geni_serial_pm_ops = {
2036 	SET_RUNTIME_PM_OPS(qcom_geni_serial_runtime_suspend,
2037 			   qcom_geni_serial_runtime_resume, NULL)
2038 	SYSTEM_SLEEP_PM_OPS(qcom_geni_serial_suspend, qcom_geni_serial_resume)
2039 };
2040 
2041 static const struct of_device_id qcom_geni_serial_match_table[] = {
2042 	{
2043 		.compatible = "qcom,geni-debug-uart",
2044 		.data = &qcom_geni_console_data,
2045 	},
2046 	{
2047 		.compatible = "qcom,sa8255p-geni-debug-uart",
2048 		.data = &sa8255p_qcom_geni_console_data,
2049 	},
2050 	{
2051 		.compatible = "qcom,geni-uart",
2052 		.data = &qcom_geni_uart_data,
2053 	},
2054 	{
2055 		.compatible = "qcom,sa8255p-geni-uart",
2056 		.data = &sa8255p_qcom_geni_uart_data,
2057 	},
2058 	{}
2059 };
2060 MODULE_DEVICE_TABLE(of, qcom_geni_serial_match_table);
2061 
2062 static struct platform_driver qcom_geni_serial_platform_driver = {
2063 	.remove = qcom_geni_serial_remove,
2064 	.probe = qcom_geni_serial_probe,
2065 	.driver = {
2066 		.name = "qcom_geni_serial",
2067 		.of_match_table = qcom_geni_serial_match_table,
2068 		.pm = &qcom_geni_serial_pm_ops,
2069 	},
2070 };
2071 
2072 static int __init qcom_geni_serial_init(void)
2073 {
2074 	int ret;
2075 
2076 	ret = console_register(&qcom_geni_console_driver);
2077 	if (ret)
2078 		return ret;
2079 
2080 	ret = uart_register_driver(&qcom_geni_uart_driver);
2081 	if (ret) {
2082 		console_unregister(&qcom_geni_console_driver);
2083 		return ret;
2084 	}
2085 
2086 	ret = platform_driver_register(&qcom_geni_serial_platform_driver);
2087 	if (ret) {
2088 		console_unregister(&qcom_geni_console_driver);
2089 		uart_unregister_driver(&qcom_geni_uart_driver);
2090 	}
2091 	return ret;
2092 }
2093 module_init(qcom_geni_serial_init);
2094 
2095 static void __exit qcom_geni_serial_exit(void)
2096 {
2097 	platform_driver_unregister(&qcom_geni_serial_platform_driver);
2098 	console_unregister(&qcom_geni_console_driver);
2099 	uart_unregister_driver(&qcom_geni_uart_driver);
2100 }
2101 module_exit(qcom_geni_serial_exit);
2102 
2103 MODULE_DESCRIPTION("Serial driver for GENI based QUP cores");
2104 MODULE_LICENSE("GPL v2");
2105