xref: /linux/drivers/tty/serial/qcom_geni_serial.c (revision d8b78066f4c9c8ec898bd4246fc4db31d476dd88)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
3 
4 /* Disable MMIO tracing to prevent excessive logging of unwanted MMIO traces */
5 #define __DISABLE_TRACE_MMIO__
6 
7 #include <linux/clk.h>
8 #include <linux/console.h>
9 #include <linux/io.h>
10 #include <linux/iopoll.h>
11 #include <linux/irq.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/pm_opp.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/pm_wakeirq.h>
18 #include <linux/soc/qcom/geni-se.h>
19 #include <linux/serial.h>
20 #include <linux/serial_core.h>
21 #include <linux/slab.h>
22 #include <linux/tty.h>
23 #include <linux/tty_flip.h>
24 #include <dt-bindings/interconnect/qcom,icc.h>
25 
26 /* UART specific GENI registers */
27 #define SE_UART_LOOPBACK_CFG		0x22c
28 #define SE_UART_IO_MACRO_CTRL		0x240
29 #define SE_UART_TX_TRANS_CFG		0x25c
30 #define SE_UART_TX_WORD_LEN		0x268
31 #define SE_UART_TX_STOP_BIT_LEN		0x26c
32 #define SE_UART_TX_TRANS_LEN		0x270
33 #define SE_UART_RX_TRANS_CFG		0x280
34 #define SE_UART_RX_WORD_LEN		0x28c
35 #define SE_UART_RX_STALE_CNT		0x294
36 #define SE_UART_TX_PARITY_CFG		0x2a4
37 #define SE_UART_RX_PARITY_CFG		0x2a8
38 #define SE_UART_MANUAL_RFR		0x2ac
39 
40 /* SE_UART_TRANS_CFG */
41 #define UART_TX_PAR_EN			BIT(0)
42 #define UART_CTS_MASK			BIT(1)
43 
44 /* SE_UART_TX_STOP_BIT_LEN */
45 #define TX_STOP_BIT_LEN_1		0
46 #define TX_STOP_BIT_LEN_2		2
47 
48 /* SE_UART_RX_TRANS_CFG */
49 #define UART_RX_PAR_EN			BIT(3)
50 
51 /* SE_UART_RX_WORD_LEN */
52 #define RX_WORD_LEN_MASK		GENMASK(9, 0)
53 
54 /* SE_UART_RX_STALE_CNT */
55 #define RX_STALE_CNT			GENMASK(23, 0)
56 
57 /* SE_UART_TX_PARITY_CFG/RX_PARITY_CFG */
58 #define PAR_CALC_EN			BIT(0)
59 #define PAR_EVEN			0x00
60 #define PAR_ODD				0x01
61 #define PAR_SPACE			0x10
62 
63 /* SE_UART_MANUAL_RFR register fields */
64 #define UART_MANUAL_RFR_EN		BIT(31)
65 #define UART_RFR_NOT_READY		BIT(1)
66 #define UART_RFR_READY			BIT(0)
67 
68 /* UART M_CMD OP codes */
69 #define UART_START_TX			0x1
70 /* UART S_CMD OP codes */
71 #define UART_START_READ			0x1
72 #define UART_PARAM			0x1
73 #define UART_PARAM_RFR_OPEN		BIT(7)
74 
75 #define UART_OVERSAMPLING		32
76 #define STALE_TIMEOUT			16
77 #define DEFAULT_BITS_PER_CHAR		10
78 #define GENI_UART_CONS_PORTS		1
79 #define GENI_UART_PORTS			3
80 #define DEF_FIFO_DEPTH_WORDS		16
81 #define DEF_TX_WM			2
82 #define DEF_FIFO_WIDTH_BITS		32
83 #define UART_RX_WM			2
84 
85 /* SE_UART_LOOPBACK_CFG */
86 #define RX_TX_SORTED			BIT(0)
87 #define CTS_RTS_SORTED			BIT(1)
88 #define RX_TX_CTS_RTS_SORTED		(RX_TX_SORTED | CTS_RTS_SORTED)
89 
90 /* UART pin swap value */
91 #define DEFAULT_IO_MACRO_IO0_IO1_MASK	GENMASK(3, 0)
92 #define IO_MACRO_IO0_SEL		0x3
93 #define DEFAULT_IO_MACRO_IO2_IO3_MASK	GENMASK(15, 4)
94 #define IO_MACRO_IO2_IO3_SWAP		0x4640
95 
96 /* We always configure 4 bytes per FIFO word */
97 #define BYTES_PER_FIFO_WORD		4U
98 
99 #define DMA_RX_BUF_SIZE		2048
100 
101 struct qcom_geni_device_data {
102 	bool console;
103 	enum geni_se_xfer_mode mode;
104 };
105 
106 struct qcom_geni_private_data {
107 	/* NOTE: earlycon port will have NULL here */
108 	struct uart_driver *drv;
109 
110 	u32 poll_cached_bytes;
111 	unsigned int poll_cached_bytes_cnt;
112 
113 	u32 write_cached_bytes;
114 	unsigned int write_cached_bytes_cnt;
115 };
116 
117 struct qcom_geni_serial_port {
118 	struct uart_port uport;
119 	struct geni_se se;
120 	const char *name;
121 	u32 tx_fifo_depth;
122 	u32 tx_fifo_width;
123 	u32 rx_fifo_depth;
124 	dma_addr_t tx_dma_addr;
125 	dma_addr_t rx_dma_addr;
126 	bool setup;
127 	unsigned long poll_timeout_us;
128 	unsigned long clk_rate;
129 	void *rx_buf;
130 	u32 loopback;
131 	bool brk;
132 
133 	unsigned int tx_remaining;
134 	unsigned int tx_queued;
135 	int wakeup_irq;
136 	bool rx_tx_swap;
137 	bool cts_rts_swap;
138 
139 	struct qcom_geni_private_data private_data;
140 	const struct qcom_geni_device_data *dev_data;
141 };
142 
143 static const struct uart_ops qcom_geni_console_pops;
144 static const struct uart_ops qcom_geni_uart_pops;
145 static struct uart_driver qcom_geni_console_driver;
146 static struct uart_driver qcom_geni_uart_driver;
147 
148 static void __qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport);
149 static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport);
150 static int qcom_geni_serial_port_setup(struct uart_port *uport);
151 
to_dev_port(struct uart_port * uport)152 static inline struct qcom_geni_serial_port *to_dev_port(struct uart_port *uport)
153 {
154 	return container_of(uport, struct qcom_geni_serial_port, uport);
155 }
156 
157 static struct qcom_geni_serial_port qcom_geni_uart_ports[GENI_UART_PORTS] = {
158 	[0] = {
159 		.uport = {
160 			.iotype = UPIO_MEM,
161 			.ops = &qcom_geni_uart_pops,
162 			.flags = UPF_BOOT_AUTOCONF,
163 			.line = 0,
164 		},
165 	},
166 	[1] = {
167 		.uport = {
168 			.iotype = UPIO_MEM,
169 			.ops = &qcom_geni_uart_pops,
170 			.flags = UPF_BOOT_AUTOCONF,
171 			.line = 1,
172 		},
173 	},
174 	[2] = {
175 		.uport = {
176 			.iotype = UPIO_MEM,
177 			.ops = &qcom_geni_uart_pops,
178 			.flags = UPF_BOOT_AUTOCONF,
179 			.line = 2,
180 		},
181 	},
182 };
183 
184 static struct qcom_geni_serial_port qcom_geni_console_port = {
185 	.uport = {
186 		.iotype = UPIO_MEM,
187 		.ops = &qcom_geni_console_pops,
188 		.flags = UPF_BOOT_AUTOCONF,
189 		.line = 0,
190 	},
191 };
192 
qcom_geni_serial_request_port(struct uart_port * uport)193 static int qcom_geni_serial_request_port(struct uart_port *uport)
194 {
195 	struct platform_device *pdev = to_platform_device(uport->dev);
196 	struct qcom_geni_serial_port *port = to_dev_port(uport);
197 
198 	uport->membase = devm_platform_ioremap_resource(pdev, 0);
199 	if (IS_ERR(uport->membase))
200 		return PTR_ERR(uport->membase);
201 	port->se.base = uport->membase;
202 	return 0;
203 }
204 
qcom_geni_serial_config_port(struct uart_port * uport,int cfg_flags)205 static void qcom_geni_serial_config_port(struct uart_port *uport, int cfg_flags)
206 {
207 	if (cfg_flags & UART_CONFIG_TYPE) {
208 		uport->type = PORT_MSM;
209 		qcom_geni_serial_request_port(uport);
210 	}
211 }
212 
qcom_geni_serial_get_mctrl(struct uart_port * uport)213 static unsigned int qcom_geni_serial_get_mctrl(struct uart_port *uport)
214 {
215 	unsigned int mctrl = TIOCM_DSR | TIOCM_CAR;
216 	u32 geni_ios;
217 
218 	if (uart_console(uport)) {
219 		mctrl |= TIOCM_CTS;
220 	} else {
221 		geni_ios = readl(uport->membase + SE_GENI_IOS);
222 		if (!(geni_ios & IO2_DATA_IN))
223 			mctrl |= TIOCM_CTS;
224 	}
225 
226 	return mctrl;
227 }
228 
qcom_geni_serial_set_mctrl(struct uart_port * uport,unsigned int mctrl)229 static void qcom_geni_serial_set_mctrl(struct uart_port *uport,
230 							unsigned int mctrl)
231 {
232 	u32 uart_manual_rfr = 0;
233 	struct qcom_geni_serial_port *port = to_dev_port(uport);
234 
235 	if (uart_console(uport))
236 		return;
237 
238 	if (mctrl & TIOCM_LOOP)
239 		port->loopback = RX_TX_CTS_RTS_SORTED;
240 
241 	if (!(mctrl & TIOCM_RTS) && !uport->suspended)
242 		uart_manual_rfr = UART_MANUAL_RFR_EN | UART_RFR_NOT_READY;
243 	writel(uart_manual_rfr, uport->membase + SE_UART_MANUAL_RFR);
244 }
245 
qcom_geni_serial_get_type(struct uart_port * uport)246 static const char *qcom_geni_serial_get_type(struct uart_port *uport)
247 {
248 	return "MSM";
249 }
250 
get_port_from_line(int line,bool console)251 static struct qcom_geni_serial_port *get_port_from_line(int line, bool console)
252 {
253 	struct qcom_geni_serial_port *port;
254 	int nr_ports = console ? GENI_UART_CONS_PORTS : GENI_UART_PORTS;
255 
256 	if (line < 0 || line >= nr_ports)
257 		return ERR_PTR(-ENXIO);
258 
259 	port = console ? &qcom_geni_console_port : &qcom_geni_uart_ports[line];
260 	return port;
261 }
262 
qcom_geni_serial_main_active(struct uart_port * uport)263 static bool qcom_geni_serial_main_active(struct uart_port *uport)
264 {
265 	return readl(uport->membase + SE_GENI_STATUS) & M_GENI_CMD_ACTIVE;
266 }
267 
qcom_geni_serial_secondary_active(struct uart_port * uport)268 static bool qcom_geni_serial_secondary_active(struct uart_port *uport)
269 {
270 	return readl(uport->membase + SE_GENI_STATUS) & S_GENI_CMD_ACTIVE;
271 }
272 
qcom_geni_serial_poll_bitfield(struct uart_port * uport,unsigned int offset,u32 field,u32 val)273 static bool qcom_geni_serial_poll_bitfield(struct uart_port *uport,
274 					   unsigned int offset, u32 field, u32 val)
275 {
276 	u32 reg;
277 	struct qcom_geni_serial_port *port;
278 	unsigned long timeout_us = 20000;
279 	struct qcom_geni_private_data *private_data = uport->private_data;
280 
281 	if (private_data->drv) {
282 		port = to_dev_port(uport);
283 		if (port->poll_timeout_us)
284 			timeout_us = port->poll_timeout_us;
285 	}
286 
287 	/*
288 	 * Use custom implementation instead of readl_poll_atomic since ktimer
289 	 * is not ready at the time of early console.
290 	 */
291 	timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10;
292 	while (timeout_us) {
293 		reg = readl(uport->membase + offset);
294 		if ((reg & field) == val)
295 			return true;
296 		udelay(10);
297 		timeout_us -= 10;
298 	}
299 	return false;
300 }
301 
qcom_geni_serial_poll_bit(struct uart_port * uport,unsigned int offset,u32 field,bool set)302 static bool qcom_geni_serial_poll_bit(struct uart_port *uport,
303 				      unsigned int offset, u32 field, bool set)
304 {
305 	return qcom_geni_serial_poll_bitfield(uport, offset, field, set ? field : 0);
306 }
307 
qcom_geni_serial_setup_tx(struct uart_port * uport,u32 xmit_size)308 static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size)
309 {
310 	u32 m_cmd;
311 
312 	writel(xmit_size, uport->membase + SE_UART_TX_TRANS_LEN);
313 	m_cmd = UART_START_TX << M_OPCODE_SHFT;
314 	writel(m_cmd, uport->membase + SE_GENI_M_CMD0);
315 }
316 
qcom_geni_serial_poll_tx_done(struct uart_port * uport)317 static void qcom_geni_serial_poll_tx_done(struct uart_port *uport)
318 {
319 	int done;
320 
321 	done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
322 						M_CMD_DONE_EN, true);
323 	if (!done) {
324 		writel(M_GENI_CMD_ABORT, uport->membase +
325 						SE_GENI_M_CMD_CTRL_REG);
326 		qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
327 							M_CMD_ABORT_EN, true);
328 		writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
329 	}
330 }
331 
qcom_geni_serial_abort_rx(struct uart_port * uport)332 static void qcom_geni_serial_abort_rx(struct uart_port *uport)
333 {
334 	u32 irq_clear = S_CMD_DONE_EN | S_CMD_ABORT_EN;
335 
336 	writel(S_GENI_CMD_ABORT, uport->membase + SE_GENI_S_CMD_CTRL_REG);
337 	qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG,
338 					S_GENI_CMD_ABORT, false);
339 	writel(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR);
340 	writel(FORCE_DEFAULT, uport->membase + GENI_FORCE_DEFAULT_REG);
341 }
342 
343 #ifdef CONFIG_CONSOLE_POLL
qcom_geni_serial_get_char(struct uart_port * uport)344 static int qcom_geni_serial_get_char(struct uart_port *uport)
345 {
346 	struct qcom_geni_private_data *private_data = uport->private_data;
347 	u32 status;
348 	u32 word_cnt;
349 	int ret;
350 
351 	if (!private_data->poll_cached_bytes_cnt) {
352 		status = readl(uport->membase + SE_GENI_M_IRQ_STATUS);
353 		writel(status, uport->membase + SE_GENI_M_IRQ_CLEAR);
354 
355 		status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
356 		writel(status, uport->membase + SE_GENI_S_IRQ_CLEAR);
357 
358 		status = readl(uport->membase + SE_GENI_RX_FIFO_STATUS);
359 		word_cnt = status & RX_FIFO_WC_MSK;
360 		if (!word_cnt)
361 			return NO_POLL_CHAR;
362 
363 		if (word_cnt == 1 && (status & RX_LAST))
364 			/*
365 			 * NOTE: If RX_LAST_BYTE_VALID is 0 it needs to be
366 			 * treated as if it was BYTES_PER_FIFO_WORD.
367 			 */
368 			private_data->poll_cached_bytes_cnt =
369 				(status & RX_LAST_BYTE_VALID_MSK) >>
370 				RX_LAST_BYTE_VALID_SHFT;
371 
372 		if (private_data->poll_cached_bytes_cnt == 0)
373 			private_data->poll_cached_bytes_cnt = BYTES_PER_FIFO_WORD;
374 
375 		private_data->poll_cached_bytes =
376 			readl(uport->membase + SE_GENI_RX_FIFOn);
377 	}
378 
379 	private_data->poll_cached_bytes_cnt--;
380 	ret = private_data->poll_cached_bytes & 0xff;
381 	private_data->poll_cached_bytes >>= 8;
382 
383 	return ret;
384 }
385 
qcom_geni_serial_poll_put_char(struct uart_port * uport,unsigned char c)386 static void qcom_geni_serial_poll_put_char(struct uart_port *uport,
387 							unsigned char c)
388 {
389 	if (qcom_geni_serial_main_active(uport)) {
390 		qcom_geni_serial_poll_tx_done(uport);
391 		__qcom_geni_serial_cancel_tx_cmd(uport);
392 	}
393 
394 	writel(M_CMD_DONE_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
395 	qcom_geni_serial_setup_tx(uport, 1);
396 	writel(c, uport->membase + SE_GENI_TX_FIFOn);
397 	qcom_geni_serial_poll_tx_done(uport);
398 }
399 
qcom_geni_serial_poll_init(struct uart_port * uport)400 static int qcom_geni_serial_poll_init(struct uart_port *uport)
401 {
402 	struct qcom_geni_serial_port *port = to_dev_port(uport);
403 	int ret;
404 
405 	if (!port->setup) {
406 		ret = qcom_geni_serial_port_setup(uport);
407 		if (ret)
408 			return ret;
409 	}
410 
411 	if (!qcom_geni_serial_secondary_active(uport))
412 		geni_se_setup_s_cmd(&port->se, UART_START_READ, 0);
413 
414 	return 0;
415 }
416 #endif
417 
418 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
qcom_geni_serial_drain_fifo(struct uart_port * uport)419 static void qcom_geni_serial_drain_fifo(struct uart_port *uport)
420 {
421 	struct qcom_geni_serial_port *port = to_dev_port(uport);
422 
423 	qcom_geni_serial_poll_bitfield(uport, SE_GENI_M_GP_LENGTH, GP_LENGTH,
424 			port->tx_queued);
425 }
426 
qcom_geni_serial_wr_char(struct uart_port * uport,unsigned char ch)427 static void qcom_geni_serial_wr_char(struct uart_port *uport, unsigned char ch)
428 {
429 	struct qcom_geni_private_data *private_data = uport->private_data;
430 
431 	private_data->write_cached_bytes =
432 		(private_data->write_cached_bytes >> 8) | (ch << 24);
433 	private_data->write_cached_bytes_cnt++;
434 
435 	if (private_data->write_cached_bytes_cnt == BYTES_PER_FIFO_WORD) {
436 		writel(private_data->write_cached_bytes,
437 		       uport->membase + SE_GENI_TX_FIFOn);
438 		private_data->write_cached_bytes_cnt = 0;
439 	}
440 }
441 
442 static void
__qcom_geni_serial_console_write(struct uart_port * uport,const char * s,unsigned int count)443 __qcom_geni_serial_console_write(struct uart_port *uport, const char *s,
444 				 unsigned int count)
445 {
446 	struct qcom_geni_private_data *private_data = uport->private_data;
447 
448 	int i;
449 	u32 bytes_to_send = count;
450 
451 	for (i = 0; i < count; i++) {
452 		/*
453 		 * uart_console_write() adds a carriage return for each newline.
454 		 * Account for additional bytes to be written.
455 		 */
456 		if (s[i] == '\n')
457 			bytes_to_send++;
458 	}
459 
460 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
461 	writel(M_CMD_DONE_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
462 	qcom_geni_serial_setup_tx(uport, bytes_to_send);
463 	for (i = 0; i < count; ) {
464 		size_t chars_to_write = 0;
465 		size_t avail = DEF_FIFO_DEPTH_WORDS - DEF_TX_WM;
466 
467 		/*
468 		 * If the WM bit never set, then the Tx state machine is not
469 		 * in a valid state, so break, cancel/abort any existing
470 		 * command. Unfortunately the current data being written is
471 		 * lost.
472 		 */
473 		if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
474 						M_TX_FIFO_WATERMARK_EN, true))
475 			break;
476 		chars_to_write = min_t(size_t, count - i, avail / 2);
477 		uart_console_write(uport, s + i, chars_to_write,
478 						qcom_geni_serial_wr_char);
479 		writel(M_TX_FIFO_WATERMARK_EN, uport->membase +
480 							SE_GENI_M_IRQ_CLEAR);
481 		i += chars_to_write;
482 	}
483 
484 	if (private_data->write_cached_bytes_cnt) {
485 		private_data->write_cached_bytes >>= BITS_PER_BYTE *
486 			(BYTES_PER_FIFO_WORD - private_data->write_cached_bytes_cnt);
487 		writel(private_data->write_cached_bytes,
488 		       uport->membase + SE_GENI_TX_FIFOn);
489 		private_data->write_cached_bytes_cnt = 0;
490 	}
491 
492 	qcom_geni_serial_poll_tx_done(uport);
493 }
494 
qcom_geni_serial_console_write(struct console * co,const char * s,unsigned int count)495 static void qcom_geni_serial_console_write(struct console *co, const char *s,
496 			      unsigned int count)
497 {
498 	struct uart_port *uport;
499 	struct qcom_geni_serial_port *port;
500 	u32 m_irq_en, s_irq_en;
501 	bool locked = true;
502 	unsigned long flags;
503 
504 	WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS);
505 
506 	port = get_port_from_line(co->index, true);
507 	if (IS_ERR(port))
508 		return;
509 
510 	uport = &port->uport;
511 	if (oops_in_progress)
512 		locked = uart_port_trylock_irqsave(uport, &flags);
513 	else
514 		uart_port_lock_irqsave(uport, &flags);
515 
516 	m_irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
517 	s_irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
518 	writel(0, uport->membase + SE_GENI_M_IRQ_EN);
519 	writel(0, uport->membase + SE_GENI_S_IRQ_EN);
520 
521 	if (qcom_geni_serial_main_active(uport)) {
522 		/* Wait for completion or drain FIFO */
523 		if (!locked || port->tx_remaining == 0)
524 			qcom_geni_serial_poll_tx_done(uport);
525 		else
526 			qcom_geni_serial_drain_fifo(uport);
527 
528 		qcom_geni_serial_cancel_tx_cmd(uport);
529 	}
530 
531 	__qcom_geni_serial_console_write(uport, s, count);
532 
533 	writel(m_irq_en, uport->membase + SE_GENI_M_IRQ_EN);
534 	writel(s_irq_en, uport->membase + SE_GENI_S_IRQ_EN);
535 
536 	if (locked)
537 		uart_port_unlock_irqrestore(uport, flags);
538 }
539 
handle_rx_console(struct uart_port * uport,u32 bytes,bool drop)540 static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
541 {
542 	u32 i;
543 	unsigned char buf[sizeof(u32)];
544 	struct tty_port *tport;
545 	struct qcom_geni_serial_port *port = to_dev_port(uport);
546 
547 	tport = &uport->state->port;
548 	for (i = 0; i < bytes; ) {
549 		int c;
550 		int chunk = min_t(int, bytes - i, BYTES_PER_FIFO_WORD);
551 
552 		ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1);
553 		i += chunk;
554 		if (drop)
555 			continue;
556 
557 		for (c = 0; c < chunk; c++) {
558 			int sysrq;
559 
560 			uport->icount.rx++;
561 			if (port->brk && buf[c] == 0) {
562 				port->brk = false;
563 				if (uart_handle_break(uport))
564 					continue;
565 			}
566 
567 			sysrq = uart_prepare_sysrq_char(uport, buf[c]);
568 
569 			if (!sysrq)
570 				tty_insert_flip_char(tport, buf[c], TTY_NORMAL);
571 		}
572 	}
573 	if (!drop)
574 		tty_flip_buffer_push(tport);
575 }
576 #else
handle_rx_console(struct uart_port * uport,u32 bytes,bool drop)577 static void handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
578 {
579 
580 }
581 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
582 
handle_rx_uart(struct uart_port * uport,u32 bytes)583 static void handle_rx_uart(struct uart_port *uport, u32 bytes)
584 {
585 	struct qcom_geni_serial_port *port = to_dev_port(uport);
586 	struct tty_port *tport = &uport->state->port;
587 	int ret;
588 
589 	ret = tty_insert_flip_string(tport, port->rx_buf, bytes);
590 	if (ret != bytes) {
591 		dev_err_ratelimited(uport->dev, "failed to push data (%d < %u)\n",
592 				ret, bytes);
593 	}
594 	uport->icount.rx += ret;
595 	tty_flip_buffer_push(tport);
596 }
597 
qcom_geni_serial_tx_empty(struct uart_port * uport)598 static unsigned int qcom_geni_serial_tx_empty(struct uart_port *uport)
599 {
600 	return !readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
601 }
602 
qcom_geni_serial_stop_tx_dma(struct uart_port * uport)603 static void qcom_geni_serial_stop_tx_dma(struct uart_port *uport)
604 {
605 	struct qcom_geni_serial_port *port = to_dev_port(uport);
606 	bool done;
607 
608 	if (!qcom_geni_serial_main_active(uport))
609 		return;
610 
611 	if (port->tx_dma_addr) {
612 		geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr,
613 				      port->tx_remaining);
614 		port->tx_dma_addr = 0;
615 		port->tx_remaining = 0;
616 	}
617 
618 	geni_se_cancel_m_cmd(&port->se);
619 
620 	done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
621 					 M_CMD_CANCEL_EN, true);
622 	if (!done) {
623 		geni_se_abort_m_cmd(&port->se);
624 		done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
625 						 M_CMD_ABORT_EN, true);
626 		if (!done)
627 			dev_err_ratelimited(uport->dev, "M_CMD_ABORT_EN not set");
628 		writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
629 	}
630 
631 	writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
632 }
633 
qcom_geni_serial_start_tx_dma(struct uart_port * uport)634 static void qcom_geni_serial_start_tx_dma(struct uart_port *uport)
635 {
636 	struct qcom_geni_serial_port *port = to_dev_port(uport);
637 	struct tty_port *tport = &uport->state->port;
638 	unsigned int xmit_size;
639 	u8 *tail;
640 	int ret;
641 
642 	if (port->tx_dma_addr)
643 		return;
644 
645 	if (kfifo_is_empty(&tport->xmit_fifo))
646 		return;
647 
648 	xmit_size = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail,
649 			UART_XMIT_SIZE);
650 
651 	qcom_geni_serial_setup_tx(uport, xmit_size);
652 
653 	ret = geni_se_tx_dma_prep(&port->se, tail, xmit_size,
654 				  &port->tx_dma_addr);
655 	if (ret) {
656 		dev_err(uport->dev, "unable to start TX SE DMA: %d\n", ret);
657 		qcom_geni_serial_stop_tx_dma(uport);
658 		return;
659 	}
660 
661 	port->tx_remaining = xmit_size;
662 }
663 
qcom_geni_serial_start_tx_fifo(struct uart_port * uport)664 static void qcom_geni_serial_start_tx_fifo(struct uart_port *uport)
665 {
666 	unsigned char c;
667 	u32 irq_en;
668 
669 	/*
670 	 * Start a new transfer in case the previous command was cancelled and
671 	 * left data in the FIFO which may prevent the watermark interrupt
672 	 * from triggering. Note that the stale data is discarded.
673 	 */
674 	if (!qcom_geni_serial_main_active(uport) &&
675 	    !qcom_geni_serial_tx_empty(uport)) {
676 		if (uart_fifo_out(uport, &c, 1) == 1) {
677 			writel(M_CMD_DONE_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
678 			qcom_geni_serial_setup_tx(uport, 1);
679 			writel(c, uport->membase + SE_GENI_TX_FIFOn);
680 		}
681 	}
682 
683 	irq_en = readl(uport->membase +	SE_GENI_M_IRQ_EN);
684 	irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
685 	writel(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
686 	writel(irq_en, uport->membase +	SE_GENI_M_IRQ_EN);
687 }
688 
qcom_geni_serial_stop_tx_fifo(struct uart_port * uport)689 static void qcom_geni_serial_stop_tx_fifo(struct uart_port *uport)
690 {
691 	u32 irq_en;
692 
693 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
694 	irq_en &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
695 	writel(0, uport->membase + SE_GENI_TX_WATERMARK_REG);
696 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
697 }
698 
__qcom_geni_serial_cancel_tx_cmd(struct uart_port * uport)699 static void __qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport)
700 {
701 	struct qcom_geni_serial_port *port = to_dev_port(uport);
702 
703 	geni_se_cancel_m_cmd(&port->se);
704 	if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
705 						M_CMD_CANCEL_EN, true)) {
706 		geni_se_abort_m_cmd(&port->se);
707 		qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
708 						M_CMD_ABORT_EN, true);
709 		writel(M_CMD_ABORT_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
710 	}
711 	writel(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
712 }
713 
qcom_geni_serial_cancel_tx_cmd(struct uart_port * uport)714 static void qcom_geni_serial_cancel_tx_cmd(struct uart_port *uport)
715 {
716 	struct qcom_geni_serial_port *port = to_dev_port(uport);
717 
718 	if (!qcom_geni_serial_main_active(uport))
719 		return;
720 
721 	__qcom_geni_serial_cancel_tx_cmd(uport);
722 
723 	port->tx_remaining = 0;
724 	port->tx_queued = 0;
725 }
726 
qcom_geni_serial_handle_rx_fifo(struct uart_port * uport,bool drop)727 static void qcom_geni_serial_handle_rx_fifo(struct uart_port *uport, bool drop)
728 {
729 	u32 status;
730 	u32 word_cnt;
731 	u32 last_word_byte_cnt;
732 	u32 last_word_partial;
733 	u32 total_bytes;
734 
735 	status = readl(uport->membase +	SE_GENI_RX_FIFO_STATUS);
736 	word_cnt = status & RX_FIFO_WC_MSK;
737 	last_word_partial = status & RX_LAST;
738 	last_word_byte_cnt = (status & RX_LAST_BYTE_VALID_MSK) >>
739 						RX_LAST_BYTE_VALID_SHFT;
740 
741 	if (!word_cnt)
742 		return;
743 	total_bytes = BYTES_PER_FIFO_WORD * (word_cnt - 1);
744 	if (last_word_partial && last_word_byte_cnt)
745 		total_bytes += last_word_byte_cnt;
746 	else
747 		total_bytes += BYTES_PER_FIFO_WORD;
748 	handle_rx_console(uport, total_bytes, drop);
749 }
750 
qcom_geni_serial_stop_rx_fifo(struct uart_port * uport)751 static void qcom_geni_serial_stop_rx_fifo(struct uart_port *uport)
752 {
753 	u32 irq_en;
754 	struct qcom_geni_serial_port *port = to_dev_port(uport);
755 	u32 s_irq_status;
756 
757 	irq_en = readl(uport->membase + SE_GENI_S_IRQ_EN);
758 	irq_en &= ~(S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN);
759 	writel(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
760 
761 	irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
762 	irq_en &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
763 	writel(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
764 
765 	if (!qcom_geni_serial_secondary_active(uport))
766 		return;
767 
768 	geni_se_cancel_s_cmd(&port->se);
769 	qcom_geni_serial_poll_bit(uport, SE_GENI_S_IRQ_STATUS,
770 					S_CMD_CANCEL_EN, true);
771 	/*
772 	 * If timeout occurs secondary engine remains active
773 	 * and Abort sequence is executed.
774 	 */
775 	s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
776 	/* Flush the Rx buffer */
777 	if (s_irq_status & S_RX_FIFO_LAST_EN)
778 		qcom_geni_serial_handle_rx_fifo(uport, true);
779 	writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
780 
781 	if (qcom_geni_serial_secondary_active(uport))
782 		qcom_geni_serial_abort_rx(uport);
783 }
784 
qcom_geni_serial_start_rx_fifo(struct uart_port * uport)785 static void qcom_geni_serial_start_rx_fifo(struct uart_port *uport)
786 {
787 	u32 irq_en;
788 	struct qcom_geni_serial_port *port = to_dev_port(uport);
789 
790 	if (qcom_geni_serial_secondary_active(uport))
791 		qcom_geni_serial_stop_rx_fifo(uport);
792 
793 	geni_se_setup_s_cmd(&port->se, UART_START_READ, 0);
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 
qcom_geni_serial_stop_rx_dma(struct uart_port * uport)804 static void qcom_geni_serial_stop_rx_dma(struct uart_port *uport)
805 {
806 	struct qcom_geni_serial_port *port = to_dev_port(uport);
807 	bool done;
808 
809 	if (!qcom_geni_serial_secondary_active(uport))
810 		return;
811 
812 	geni_se_cancel_s_cmd(&port->se);
813 	done = qcom_geni_serial_poll_bit(uport, SE_DMA_RX_IRQ_STAT,
814 			RX_EOT, true);
815 	if (done) {
816 		writel(RX_EOT | RX_DMA_DONE,
817 				uport->membase + SE_DMA_RX_IRQ_CLR);
818 	} else {
819 		qcom_geni_serial_abort_rx(uport);
820 
821 		writel(1, uport->membase + SE_DMA_RX_FSM_RST);
822 		qcom_geni_serial_poll_bit(uport, SE_DMA_RX_IRQ_STAT,
823 				RX_RESET_DONE, true);
824 		writel(RX_RESET_DONE | RX_DMA_DONE,
825 				uport->membase + SE_DMA_RX_IRQ_CLR);
826 	}
827 
828 	if (port->rx_dma_addr) {
829 		geni_se_rx_dma_unprep(&port->se, port->rx_dma_addr,
830 				      DMA_RX_BUF_SIZE);
831 		port->rx_dma_addr = 0;
832 	}
833 }
834 
qcom_geni_serial_start_rx_dma(struct uart_port * uport)835 static void qcom_geni_serial_start_rx_dma(struct uart_port *uport)
836 {
837 	struct qcom_geni_serial_port *port = to_dev_port(uport);
838 	int ret;
839 
840 	if (qcom_geni_serial_secondary_active(uport))
841 		qcom_geni_serial_stop_rx_dma(uport);
842 
843 	geni_se_setup_s_cmd(&port->se, UART_START_READ, UART_PARAM_RFR_OPEN);
844 
845 	ret = geni_se_rx_dma_prep(&port->se, port->rx_buf,
846 				  DMA_RX_BUF_SIZE,
847 				  &port->rx_dma_addr);
848 	if (ret) {
849 		dev_err(uport->dev, "unable to start RX SE DMA: %d\n", ret);
850 		qcom_geni_serial_stop_rx_dma(uport);
851 	}
852 }
853 
qcom_geni_serial_handle_rx_dma(struct uart_port * uport,bool drop)854 static void qcom_geni_serial_handle_rx_dma(struct uart_port *uport, bool drop)
855 {
856 	struct qcom_geni_serial_port *port = to_dev_port(uport);
857 	u32 rx_in;
858 	int ret;
859 
860 	if (!qcom_geni_serial_secondary_active(uport))
861 		return;
862 
863 	if (!port->rx_dma_addr)
864 		return;
865 
866 	geni_se_rx_dma_unprep(&port->se, port->rx_dma_addr, DMA_RX_BUF_SIZE);
867 	port->rx_dma_addr = 0;
868 
869 	rx_in = readl(uport->membase + SE_DMA_RX_LEN_IN);
870 	if (!rx_in) {
871 		dev_warn(uport->dev, "serial engine reports 0 RX bytes in!\n");
872 		return;
873 	}
874 
875 	if (!drop)
876 		handle_rx_uart(uport, rx_in);
877 
878 	ret = geni_se_rx_dma_prep(&port->se, port->rx_buf,
879 				  DMA_RX_BUF_SIZE,
880 				  &port->rx_dma_addr);
881 	if (ret) {
882 		dev_err(uport->dev, "unable to start RX SE DMA: %d\n", ret);
883 		qcom_geni_serial_stop_rx_dma(uport);
884 	}
885 }
886 
qcom_geni_serial_start_rx(struct uart_port * uport)887 static void qcom_geni_serial_start_rx(struct uart_port *uport)
888 {
889 	uport->ops->start_rx(uport);
890 }
891 
qcom_geni_serial_stop_rx(struct uart_port * uport)892 static void qcom_geni_serial_stop_rx(struct uart_port *uport)
893 {
894 	uport->ops->stop_rx(uport);
895 }
896 
qcom_geni_serial_stop_tx(struct uart_port * uport)897 static void qcom_geni_serial_stop_tx(struct uart_port *uport)
898 {
899 	uport->ops->stop_tx(uport);
900 }
901 
qcom_geni_serial_send_chunk_fifo(struct uart_port * uport,unsigned int chunk)902 static void qcom_geni_serial_send_chunk_fifo(struct uart_port *uport,
903 					     unsigned int chunk)
904 {
905 	struct qcom_geni_serial_port *port = to_dev_port(uport);
906 	unsigned int tx_bytes, remaining = chunk;
907 	u8 buf[BYTES_PER_FIFO_WORD];
908 
909 	while (remaining) {
910 		memset(buf, 0, sizeof(buf));
911 		tx_bytes = min(remaining, BYTES_PER_FIFO_WORD);
912 
913 		uart_fifo_out(uport, buf, tx_bytes);
914 
915 		iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
916 
917 		remaining -= tx_bytes;
918 		port->tx_remaining -= tx_bytes;
919 	}
920 }
921 
qcom_geni_serial_handle_tx_fifo(struct uart_port * uport,bool done,bool active)922 static void qcom_geni_serial_handle_tx_fifo(struct uart_port *uport,
923 					    bool done, bool active)
924 {
925 	struct qcom_geni_serial_port *port = to_dev_port(uport);
926 	struct tty_port *tport = &uport->state->port;
927 	size_t avail;
928 	size_t pending;
929 	u32 status;
930 	u32 irq_en;
931 	unsigned int chunk;
932 
933 	status = readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
934 
935 	/* Complete the current tx command before taking newly added data */
936 	if (active)
937 		pending = port->tx_remaining;
938 	else
939 		pending = kfifo_len(&tport->xmit_fifo);
940 
941 	/* All data has been transmitted or command has been cancelled */
942 	if (!pending && done) {
943 		qcom_geni_serial_stop_tx_fifo(uport);
944 		goto out_write_wakeup;
945 	}
946 
947 	if (active)
948 		avail = port->tx_fifo_depth - (status & TX_FIFO_WC);
949 	else
950 		avail = port->tx_fifo_depth;
951 
952 	avail *= BYTES_PER_FIFO_WORD;
953 
954 	chunk = min(avail, pending);
955 	if (!chunk)
956 		goto out_write_wakeup;
957 
958 	if (!active) {
959 		qcom_geni_serial_setup_tx(uport, pending);
960 		port->tx_remaining = pending;
961 		port->tx_queued = 0;
962 
963 		irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
964 		if (!(irq_en & M_TX_FIFO_WATERMARK_EN))
965 			writel(irq_en | M_TX_FIFO_WATERMARK_EN,
966 					uport->membase + SE_GENI_M_IRQ_EN);
967 	}
968 
969 	qcom_geni_serial_send_chunk_fifo(uport, chunk);
970 	port->tx_queued += chunk;
971 
972 	/*
973 	 * The tx fifo watermark is level triggered and latched. Though we had
974 	 * cleared it in qcom_geni_serial_isr it will have already reasserted
975 	 * so we must clear it again here after our writes.
976 	 */
977 	writel(M_TX_FIFO_WATERMARK_EN,
978 			uport->membase + SE_GENI_M_IRQ_CLEAR);
979 
980 out_write_wakeup:
981 	if (!port->tx_remaining) {
982 		irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
983 		if (irq_en & M_TX_FIFO_WATERMARK_EN)
984 			writel(irq_en & ~M_TX_FIFO_WATERMARK_EN,
985 					uport->membase + SE_GENI_M_IRQ_EN);
986 	}
987 
988 	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
989 		uart_write_wakeup(uport);
990 }
991 
qcom_geni_serial_handle_tx_dma(struct uart_port * uport)992 static void qcom_geni_serial_handle_tx_dma(struct uart_port *uport)
993 {
994 	struct qcom_geni_serial_port *port = to_dev_port(uport);
995 	struct tty_port *tport = &uport->state->port;
996 
997 	uart_xmit_advance(uport, port->tx_remaining);
998 	geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr, port->tx_remaining);
999 	port->tx_dma_addr = 0;
1000 	port->tx_remaining = 0;
1001 
1002 	if (!kfifo_is_empty(&tport->xmit_fifo))
1003 		qcom_geni_serial_start_tx_dma(uport);
1004 
1005 	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
1006 		uart_write_wakeup(uport);
1007 }
1008 
qcom_geni_serial_isr(int isr,void * dev)1009 static irqreturn_t qcom_geni_serial_isr(int isr, void *dev)
1010 {
1011 	u32 m_irq_en;
1012 	u32 m_irq_status;
1013 	u32 s_irq_status;
1014 	u32 geni_status;
1015 	u32 dma;
1016 	u32 dma_tx_status;
1017 	u32 dma_rx_status;
1018 	struct uart_port *uport = dev;
1019 	bool drop_rx = false;
1020 	struct tty_port *tport = &uport->state->port;
1021 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1022 
1023 	if (uport->suspended)
1024 		return IRQ_NONE;
1025 
1026 	uart_port_lock(uport);
1027 
1028 	m_irq_status = readl(uport->membase + SE_GENI_M_IRQ_STATUS);
1029 	s_irq_status = readl(uport->membase + SE_GENI_S_IRQ_STATUS);
1030 	dma_tx_status = readl(uport->membase + SE_DMA_TX_IRQ_STAT);
1031 	dma_rx_status = readl(uport->membase + SE_DMA_RX_IRQ_STAT);
1032 	geni_status = readl(uport->membase + SE_GENI_STATUS);
1033 	dma = readl(uport->membase + SE_GENI_DMA_MODE_EN);
1034 	m_irq_en = readl(uport->membase + SE_GENI_M_IRQ_EN);
1035 	writel(m_irq_status, uport->membase + SE_GENI_M_IRQ_CLEAR);
1036 	writel(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
1037 	writel(dma_tx_status, uport->membase + SE_DMA_TX_IRQ_CLR);
1038 	writel(dma_rx_status, uport->membase + SE_DMA_RX_IRQ_CLR);
1039 
1040 	if (WARN_ON(m_irq_status & M_ILLEGAL_CMD_EN))
1041 		goto out_unlock;
1042 
1043 	if (s_irq_status & S_RX_FIFO_WR_ERR_EN) {
1044 		uport->icount.overrun++;
1045 		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
1046 	}
1047 
1048 	if (s_irq_status & (S_GP_IRQ_0_EN | S_GP_IRQ_1_EN)) {
1049 		if (s_irq_status & S_GP_IRQ_0_EN)
1050 			uport->icount.parity++;
1051 		drop_rx = true;
1052 	} else if (s_irq_status & (S_GP_IRQ_2_EN | S_GP_IRQ_3_EN)) {
1053 		uport->icount.brk++;
1054 		port->brk = true;
1055 	}
1056 
1057 	if (dma) {
1058 		if (dma_tx_status & TX_DMA_DONE)
1059 			qcom_geni_serial_handle_tx_dma(uport);
1060 
1061 		if (dma_rx_status) {
1062 			if (dma_rx_status & RX_RESET_DONE)
1063 				goto out_unlock;
1064 
1065 			if (dma_rx_status & RX_DMA_PARITY_ERR) {
1066 				uport->icount.parity++;
1067 				drop_rx = true;
1068 			}
1069 
1070 			if (dma_rx_status & RX_DMA_BREAK)
1071 				uport->icount.brk++;
1072 
1073 			if (dma_rx_status & (RX_DMA_DONE | RX_EOT))
1074 				qcom_geni_serial_handle_rx_dma(uport, drop_rx);
1075 		}
1076 	} else {
1077 		if (m_irq_status & m_irq_en &
1078 		    (M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN))
1079 			qcom_geni_serial_handle_tx_fifo(uport,
1080 					m_irq_status & M_CMD_DONE_EN,
1081 					geni_status & M_GENI_CMD_ACTIVE);
1082 
1083 		if (s_irq_status & (S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN))
1084 			qcom_geni_serial_handle_rx_fifo(uport, drop_rx);
1085 	}
1086 
1087 out_unlock:
1088 	uart_unlock_and_check_sysrq(uport);
1089 
1090 	return IRQ_HANDLED;
1091 }
1092 
setup_fifos(struct qcom_geni_serial_port * port)1093 static int setup_fifos(struct qcom_geni_serial_port *port)
1094 {
1095 	struct uart_port *uport;
1096 	u32 old_rx_fifo_depth = port->rx_fifo_depth;
1097 
1098 	uport = &port->uport;
1099 	port->tx_fifo_depth = geni_se_get_tx_fifo_depth(&port->se);
1100 	port->tx_fifo_width = geni_se_get_tx_fifo_width(&port->se);
1101 	port->rx_fifo_depth = geni_se_get_rx_fifo_depth(&port->se);
1102 	uport->fifosize =
1103 		(port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE;
1104 
1105 	if (port->rx_buf && (old_rx_fifo_depth != port->rx_fifo_depth) && port->rx_fifo_depth) {
1106 		/*
1107 		 * Use krealloc rather than krealloc_array because rx_buf is
1108 		 * accessed as 1 byte entries as well as 4 byte entries so it's
1109 		 * not necessarily an array.
1110 		 */
1111 		port->rx_buf = devm_krealloc(uport->dev, port->rx_buf,
1112 					     port->rx_fifo_depth * sizeof(u32),
1113 					     GFP_KERNEL);
1114 		if (!port->rx_buf)
1115 			return -ENOMEM;
1116 	}
1117 
1118 	return 0;
1119 }
1120 
1121 
qcom_geni_serial_shutdown(struct uart_port * uport)1122 static void qcom_geni_serial_shutdown(struct uart_port *uport)
1123 {
1124 	disable_irq(uport->irq);
1125 
1126 	uart_port_lock_irq(uport);
1127 	qcom_geni_serial_stop_tx(uport);
1128 	qcom_geni_serial_stop_rx(uport);
1129 
1130 	qcom_geni_serial_cancel_tx_cmd(uport);
1131 	uart_port_unlock_irq(uport);
1132 }
1133 
qcom_geni_serial_flush_buffer(struct uart_port * uport)1134 static void qcom_geni_serial_flush_buffer(struct uart_port *uport)
1135 {
1136 	qcom_geni_serial_cancel_tx_cmd(uport);
1137 }
1138 
qcom_geni_serial_port_setup(struct uart_port * uport)1139 static int qcom_geni_serial_port_setup(struct uart_port *uport)
1140 {
1141 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1142 	u32 rxstale = DEFAULT_BITS_PER_CHAR * STALE_TIMEOUT;
1143 	u32 proto;
1144 	u32 pin_swap;
1145 	int ret;
1146 
1147 	proto = geni_se_read_proto(&port->se);
1148 	if (proto != GENI_SE_UART) {
1149 		dev_err(uport->dev, "Invalid FW loaded, proto: %d\n", proto);
1150 		return -ENXIO;
1151 	}
1152 
1153 	qcom_geni_serial_stop_rx(uport);
1154 
1155 	ret = setup_fifos(port);
1156 	if (ret)
1157 		return ret;
1158 
1159 	writel(rxstale, uport->membase + SE_UART_RX_STALE_CNT);
1160 
1161 	pin_swap = readl(uport->membase + SE_UART_IO_MACRO_CTRL);
1162 	if (port->rx_tx_swap) {
1163 		pin_swap &= ~DEFAULT_IO_MACRO_IO2_IO3_MASK;
1164 		pin_swap |= IO_MACRO_IO2_IO3_SWAP;
1165 	}
1166 	if (port->cts_rts_swap) {
1167 		pin_swap &= ~DEFAULT_IO_MACRO_IO0_IO1_MASK;
1168 		pin_swap |= IO_MACRO_IO0_SEL;
1169 	}
1170 	/* Configure this register if RX-TX, CTS-RTS pins are swapped */
1171 	if (port->rx_tx_swap || port->cts_rts_swap)
1172 		writel(pin_swap, uport->membase + SE_UART_IO_MACRO_CTRL);
1173 
1174 	/*
1175 	 * Make an unconditional cancel on the main sequencer to reset
1176 	 * it else we could end up in data loss scenarios.
1177 	 */
1178 	if (uart_console(uport))
1179 		qcom_geni_serial_poll_tx_done(uport);
1180 	geni_se_config_packing(&port->se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
1181 			       false, true, true);
1182 	geni_se_init(&port->se, UART_RX_WM, port->rx_fifo_depth - 2);
1183 	geni_se_select_mode(&port->se, port->dev_data->mode);
1184 	port->setup = true;
1185 
1186 	return 0;
1187 }
1188 
qcom_geni_serial_startup(struct uart_port * uport)1189 static int qcom_geni_serial_startup(struct uart_port *uport)
1190 {
1191 	int ret;
1192 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1193 
1194 	if (!port->setup) {
1195 		ret = qcom_geni_serial_port_setup(uport);
1196 		if (ret)
1197 			return ret;
1198 	}
1199 
1200 	uart_port_lock_irq(uport);
1201 	qcom_geni_serial_start_rx(uport);
1202 	uart_port_unlock_irq(uport);
1203 
1204 	enable_irq(uport->irq);
1205 
1206 	return 0;
1207 }
1208 
find_clk_rate_in_tol(struct clk * clk,unsigned int desired_clk,unsigned int * clk_div,unsigned int percent_tol)1209 static unsigned long find_clk_rate_in_tol(struct clk *clk, unsigned int desired_clk,
1210 			unsigned int *clk_div, unsigned int percent_tol)
1211 {
1212 	unsigned long freq;
1213 	unsigned long div, maxdiv;
1214 	u64 mult;
1215 	unsigned long offset, abs_tol, achieved;
1216 
1217 	abs_tol = div_u64((u64)desired_clk * percent_tol, 100);
1218 	maxdiv = CLK_DIV_MSK >> CLK_DIV_SHFT;
1219 	div = 1;
1220 	while (div <= maxdiv) {
1221 		mult = (u64)div * desired_clk;
1222 		if (mult != (unsigned long)mult)
1223 			break;
1224 
1225 		offset = div * abs_tol;
1226 		freq = clk_round_rate(clk, mult - offset);
1227 
1228 		/* Can only get lower if we're done */
1229 		if (freq < mult - offset)
1230 			break;
1231 
1232 		/*
1233 		 * Re-calculate div in case rounding skipped rates but we
1234 		 * ended up at a good one, then check for a match.
1235 		 */
1236 		div = DIV_ROUND_CLOSEST(freq, desired_clk);
1237 		achieved = DIV_ROUND_CLOSEST(freq, div);
1238 		if (achieved <= desired_clk + abs_tol &&
1239 		    achieved >= desired_clk - abs_tol) {
1240 			*clk_div = div;
1241 			return freq;
1242 		}
1243 
1244 		div = DIV_ROUND_UP(freq, desired_clk);
1245 	}
1246 
1247 	return 0;
1248 }
1249 
get_clk_div_rate(struct clk * clk,unsigned int baud,unsigned int sampling_rate,unsigned int * clk_div)1250 static unsigned long get_clk_div_rate(struct clk *clk, unsigned int baud,
1251 			unsigned int sampling_rate, unsigned int *clk_div)
1252 {
1253 	unsigned long ser_clk;
1254 	unsigned long desired_clk;
1255 
1256 	desired_clk = baud * sampling_rate;
1257 	if (!desired_clk)
1258 		return 0;
1259 
1260 	/*
1261 	 * try to find a clock rate within 2% tolerance, then within 5%
1262 	 */
1263 	ser_clk = find_clk_rate_in_tol(clk, desired_clk, clk_div, 2);
1264 	if (!ser_clk)
1265 		ser_clk = find_clk_rate_in_tol(clk, desired_clk, clk_div, 5);
1266 
1267 	return ser_clk;
1268 }
1269 
qcom_geni_serial_set_termios(struct uart_port * uport,struct ktermios * termios,const struct ktermios * old)1270 static void qcom_geni_serial_set_termios(struct uart_port *uport,
1271 					 struct ktermios *termios,
1272 					 const struct ktermios *old)
1273 {
1274 	unsigned int baud;
1275 	u32 bits_per_char;
1276 	u32 tx_trans_cfg;
1277 	u32 tx_parity_cfg;
1278 	u32 rx_trans_cfg;
1279 	u32 rx_parity_cfg;
1280 	u32 stop_bit_len;
1281 	unsigned int clk_div;
1282 	u32 ser_clk_cfg;
1283 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1284 	unsigned long clk_rate;
1285 	u32 ver, sampling_rate;
1286 	unsigned int avg_bw_core;
1287 	unsigned long timeout;
1288 
1289 	/* baud rate */
1290 	baud = uart_get_baud_rate(uport, termios, old, 300, 4000000);
1291 
1292 	sampling_rate = UART_OVERSAMPLING;
1293 	/* Sampling rate is halved for IP versions >= 2.5 */
1294 	ver = geni_se_get_qup_hw_version(&port->se);
1295 	if (ver >= QUP_SE_VERSION_2_5)
1296 		sampling_rate /= 2;
1297 
1298 	clk_rate = get_clk_div_rate(port->se.clk, baud,
1299 		sampling_rate, &clk_div);
1300 	if (!clk_rate) {
1301 		dev_err(port->se.dev,
1302 			"Couldn't find suitable clock rate for %u\n",
1303 			baud * sampling_rate);
1304 		return;
1305 	}
1306 
1307 	dev_dbg(port->se.dev, "desired_rate = %u, clk_rate = %lu, clk_div = %u\n",
1308 			baud * sampling_rate, clk_rate, clk_div);
1309 
1310 	uport->uartclk = clk_rate;
1311 	port->clk_rate = clk_rate;
1312 	dev_pm_opp_set_rate(uport->dev, clk_rate);
1313 	ser_clk_cfg = SER_CLK_EN;
1314 	ser_clk_cfg |= clk_div << CLK_DIV_SHFT;
1315 
1316 	/*
1317 	 * Bump up BW vote on CPU and CORE path as driver supports FIFO mode
1318 	 * only.
1319 	 */
1320 	avg_bw_core = (baud > 115200) ? Bps_to_icc(CORE_2X_50_MHZ)
1321 						: GENI_DEFAULT_BW;
1322 	port->se.icc_paths[GENI_TO_CORE].avg_bw = avg_bw_core;
1323 	port->se.icc_paths[CPU_TO_GENI].avg_bw = Bps_to_icc(baud);
1324 	geni_icc_set_bw(&port->se);
1325 
1326 	/* parity */
1327 	tx_trans_cfg = readl(uport->membase + SE_UART_TX_TRANS_CFG);
1328 	tx_parity_cfg = readl(uport->membase + SE_UART_TX_PARITY_CFG);
1329 	rx_trans_cfg = readl(uport->membase + SE_UART_RX_TRANS_CFG);
1330 	rx_parity_cfg = readl(uport->membase + SE_UART_RX_PARITY_CFG);
1331 	if (termios->c_cflag & PARENB) {
1332 		tx_trans_cfg |= UART_TX_PAR_EN;
1333 		rx_trans_cfg |= UART_RX_PAR_EN;
1334 		tx_parity_cfg |= PAR_CALC_EN;
1335 		rx_parity_cfg |= PAR_CALC_EN;
1336 		if (termios->c_cflag & PARODD) {
1337 			tx_parity_cfg |= PAR_ODD;
1338 			rx_parity_cfg |= PAR_ODD;
1339 		} else if (termios->c_cflag & CMSPAR) {
1340 			tx_parity_cfg |= PAR_SPACE;
1341 			rx_parity_cfg |= PAR_SPACE;
1342 		} else {
1343 			tx_parity_cfg |= PAR_EVEN;
1344 			rx_parity_cfg |= PAR_EVEN;
1345 		}
1346 	} else {
1347 		tx_trans_cfg &= ~UART_TX_PAR_EN;
1348 		rx_trans_cfg &= ~UART_RX_PAR_EN;
1349 		tx_parity_cfg &= ~PAR_CALC_EN;
1350 		rx_parity_cfg &= ~PAR_CALC_EN;
1351 	}
1352 
1353 	/* bits per char */
1354 	bits_per_char = tty_get_char_size(termios->c_cflag);
1355 
1356 	/* stop bits */
1357 	if (termios->c_cflag & CSTOPB)
1358 		stop_bit_len = TX_STOP_BIT_LEN_2;
1359 	else
1360 		stop_bit_len = TX_STOP_BIT_LEN_1;
1361 
1362 	/* flow control, clear the CTS_MASK bit if using flow control. */
1363 	if (termios->c_cflag & CRTSCTS)
1364 		tx_trans_cfg &= ~UART_CTS_MASK;
1365 	else
1366 		tx_trans_cfg |= UART_CTS_MASK;
1367 
1368 	if (baud) {
1369 		uart_update_timeout(uport, termios->c_cflag, baud);
1370 
1371 		/*
1372 		 * Make sure that qcom_geni_serial_poll_bitfield() waits for
1373 		 * the FIFO, two-word intermediate transfer register and shift
1374 		 * register to clear.
1375 		 *
1376 		 * Note that uart_fifo_timeout() also adds a 20 ms margin.
1377 		 */
1378 		timeout = jiffies_to_usecs(uart_fifo_timeout(uport));
1379 		timeout += 3 * timeout / port->tx_fifo_depth;
1380 		WRITE_ONCE(port->poll_timeout_us, timeout);
1381 	}
1382 
1383 	if (!uart_console(uport))
1384 		writel(port->loopback,
1385 				uport->membase + SE_UART_LOOPBACK_CFG);
1386 	writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1387 	writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1388 	writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1389 	writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1390 	writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1391 	writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1392 	writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1393 	writel(ser_clk_cfg, uport->membase + GENI_SER_M_CLK_CFG);
1394 	writel(ser_clk_cfg, uport->membase + GENI_SER_S_CLK_CFG);
1395 }
1396 
1397 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
qcom_geni_console_setup(struct console * co,char * options)1398 static int qcom_geni_console_setup(struct console *co, char *options)
1399 {
1400 	struct uart_port *uport;
1401 	struct qcom_geni_serial_port *port;
1402 	int baud = 115200;
1403 	int bits = 8;
1404 	int parity = 'n';
1405 	int flow = 'n';
1406 	int ret;
1407 
1408 	if (co->index >= GENI_UART_CONS_PORTS  || co->index < 0)
1409 		return -ENXIO;
1410 
1411 	port = get_port_from_line(co->index, true);
1412 	if (IS_ERR(port)) {
1413 		pr_err("Invalid line %d\n", co->index);
1414 		return PTR_ERR(port);
1415 	}
1416 
1417 	uport = &port->uport;
1418 
1419 	if (unlikely(!uport->membase))
1420 		return -ENXIO;
1421 
1422 	if (!port->setup) {
1423 		ret = qcom_geni_serial_port_setup(uport);
1424 		if (ret)
1425 			return ret;
1426 	}
1427 
1428 	if (options)
1429 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1430 
1431 	return uart_set_options(uport, co, baud, parity, bits, flow);
1432 }
1433 
qcom_geni_serial_earlycon_write(struct console * con,const char * s,unsigned int n)1434 static void qcom_geni_serial_earlycon_write(struct console *con,
1435 					const char *s, unsigned int n)
1436 {
1437 	struct earlycon_device *dev = con->data;
1438 
1439 	__qcom_geni_serial_console_write(&dev->port, s, n);
1440 }
1441 
1442 #ifdef CONFIG_CONSOLE_POLL
qcom_geni_serial_earlycon_read(struct console * con,char * s,unsigned int n)1443 static int qcom_geni_serial_earlycon_read(struct console *con,
1444 					  char *s, unsigned int n)
1445 {
1446 	struct earlycon_device *dev = con->data;
1447 	struct uart_port *uport = &dev->port;
1448 	int num_read = 0;
1449 	int ch;
1450 
1451 	while (num_read < n) {
1452 		ch = qcom_geni_serial_get_char(uport);
1453 		if (ch == NO_POLL_CHAR)
1454 			break;
1455 		s[num_read++] = ch;
1456 	}
1457 
1458 	return num_read;
1459 }
1460 
qcom_geni_serial_enable_early_read(struct geni_se * se,struct console * con)1461 static void __init qcom_geni_serial_enable_early_read(struct geni_se *se,
1462 						      struct console *con)
1463 {
1464 	geni_se_setup_s_cmd(se, UART_START_READ, 0);
1465 	con->read = qcom_geni_serial_earlycon_read;
1466 }
1467 #else
qcom_geni_serial_enable_early_read(struct geni_se * se,struct console * con)1468 static inline void qcom_geni_serial_enable_early_read(struct geni_se *se,
1469 						      struct console *con) { }
1470 #endif
1471 
1472 static struct qcom_geni_private_data earlycon_private_data;
1473 
qcom_geni_serial_earlycon_setup(struct earlycon_device * dev,const char * opt)1474 static int __init qcom_geni_serial_earlycon_setup(struct earlycon_device *dev,
1475 								const char *opt)
1476 {
1477 	struct uart_port *uport = &dev->port;
1478 	u32 tx_trans_cfg;
1479 	u32 tx_parity_cfg = 0;	/* Disable Tx Parity */
1480 	u32 rx_trans_cfg = 0;
1481 	u32 rx_parity_cfg = 0;	/* Disable Rx Parity */
1482 	u32 stop_bit_len = 0;	/* Default stop bit length - 1 bit */
1483 	u32 bits_per_char;
1484 	struct geni_se se;
1485 
1486 	if (!uport->membase)
1487 		return -EINVAL;
1488 
1489 	uport->private_data = &earlycon_private_data;
1490 
1491 	memset(&se, 0, sizeof(se));
1492 	se.base = uport->membase;
1493 	if (geni_se_read_proto(&se) != GENI_SE_UART)
1494 		return -ENXIO;
1495 	/*
1496 	 * Ignore Flow control.
1497 	 * n = 8.
1498 	 */
1499 	tx_trans_cfg = UART_CTS_MASK;
1500 	bits_per_char = BITS_PER_BYTE;
1501 
1502 	/*
1503 	 * Make an unconditional cancel on the main sequencer to reset
1504 	 * it else we could end up in data loss scenarios.
1505 	 */
1506 	qcom_geni_serial_poll_tx_done(uport);
1507 	qcom_geni_serial_abort_rx(uport);
1508 	geni_se_config_packing(&se, BITS_PER_BYTE, BYTES_PER_FIFO_WORD,
1509 			       false, true, true);
1510 	geni_se_init(&se, DEF_FIFO_DEPTH_WORDS / 2, DEF_FIFO_DEPTH_WORDS - 2);
1511 	geni_se_select_mode(&se, GENI_SE_FIFO);
1512 
1513 	writel(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1514 	writel(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1515 	writel(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1516 	writel(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1517 	writel(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1518 	writel(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1519 	writel(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1520 
1521 	dev->con->write = qcom_geni_serial_earlycon_write;
1522 	dev->con->setup = NULL;
1523 	qcom_geni_serial_enable_early_read(&se, dev->con);
1524 
1525 	return 0;
1526 }
1527 OF_EARLYCON_DECLARE(qcom_geni, "qcom,geni-debug-uart",
1528 				qcom_geni_serial_earlycon_setup);
1529 
console_register(struct uart_driver * drv)1530 static int __init console_register(struct uart_driver *drv)
1531 {
1532 	return uart_register_driver(drv);
1533 }
1534 
console_unregister(struct uart_driver * drv)1535 static void console_unregister(struct uart_driver *drv)
1536 {
1537 	uart_unregister_driver(drv);
1538 }
1539 
1540 static struct console cons_ops = {
1541 	.name = "ttyMSM",
1542 	.write = qcom_geni_serial_console_write,
1543 	.device = uart_console_device,
1544 	.setup = qcom_geni_console_setup,
1545 	.flags = CON_PRINTBUFFER,
1546 	.index = -1,
1547 	.data = &qcom_geni_console_driver,
1548 };
1549 
1550 static struct uart_driver qcom_geni_console_driver = {
1551 	.owner = THIS_MODULE,
1552 	.driver_name = "qcom_geni_console",
1553 	.dev_name = "ttyMSM",
1554 	.nr =  GENI_UART_CONS_PORTS,
1555 	.cons = &cons_ops,
1556 };
1557 #else
console_register(struct uart_driver * drv)1558 static int console_register(struct uart_driver *drv)
1559 {
1560 	return 0;
1561 }
1562 
console_unregister(struct uart_driver * drv)1563 static void console_unregister(struct uart_driver *drv)
1564 {
1565 }
1566 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
1567 
1568 static struct uart_driver qcom_geni_uart_driver = {
1569 	.owner = THIS_MODULE,
1570 	.driver_name = "qcom_geni_uart",
1571 	.dev_name = "ttyHS",
1572 	.nr =  GENI_UART_PORTS,
1573 };
1574 
qcom_geni_serial_pm(struct uart_port * uport,unsigned int new_state,unsigned int old_state)1575 static void qcom_geni_serial_pm(struct uart_port *uport,
1576 		unsigned int new_state, unsigned int old_state)
1577 {
1578 	struct qcom_geni_serial_port *port = to_dev_port(uport);
1579 
1580 	/* If we've never been called, treat it as off */
1581 	if (old_state == UART_PM_STATE_UNDEFINED)
1582 		old_state = UART_PM_STATE_OFF;
1583 
1584 	if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF) {
1585 		geni_icc_enable(&port->se);
1586 		if (port->clk_rate)
1587 			dev_pm_opp_set_rate(uport->dev, port->clk_rate);
1588 		geni_se_resources_on(&port->se);
1589 	} else if (new_state == UART_PM_STATE_OFF &&
1590 			old_state == UART_PM_STATE_ON) {
1591 		geni_se_resources_off(&port->se);
1592 		dev_pm_opp_set_rate(uport->dev, 0);
1593 		geni_icc_disable(&port->se);
1594 	}
1595 }
1596 
1597 static const struct uart_ops qcom_geni_console_pops = {
1598 	.tx_empty = qcom_geni_serial_tx_empty,
1599 	.stop_tx = qcom_geni_serial_stop_tx_fifo,
1600 	.start_tx = qcom_geni_serial_start_tx_fifo,
1601 	.stop_rx = qcom_geni_serial_stop_rx_fifo,
1602 	.start_rx = qcom_geni_serial_start_rx_fifo,
1603 	.set_termios = qcom_geni_serial_set_termios,
1604 	.startup = qcom_geni_serial_startup,
1605 	.request_port = qcom_geni_serial_request_port,
1606 	.config_port = qcom_geni_serial_config_port,
1607 	.shutdown = qcom_geni_serial_shutdown,
1608 	.flush_buffer = qcom_geni_serial_flush_buffer,
1609 	.type = qcom_geni_serial_get_type,
1610 	.set_mctrl = qcom_geni_serial_set_mctrl,
1611 	.get_mctrl = qcom_geni_serial_get_mctrl,
1612 #ifdef CONFIG_CONSOLE_POLL
1613 	.poll_get_char	= qcom_geni_serial_get_char,
1614 	.poll_put_char	= qcom_geni_serial_poll_put_char,
1615 	.poll_init = qcom_geni_serial_poll_init,
1616 #endif
1617 	.pm = qcom_geni_serial_pm,
1618 };
1619 
1620 static const struct uart_ops qcom_geni_uart_pops = {
1621 	.tx_empty = qcom_geni_serial_tx_empty,
1622 	.stop_tx = qcom_geni_serial_stop_tx_dma,
1623 	.start_tx = qcom_geni_serial_start_tx_dma,
1624 	.start_rx = qcom_geni_serial_start_rx_dma,
1625 	.stop_rx = qcom_geni_serial_stop_rx_dma,
1626 	.set_termios = qcom_geni_serial_set_termios,
1627 	.startup = qcom_geni_serial_startup,
1628 	.request_port = qcom_geni_serial_request_port,
1629 	.config_port = qcom_geni_serial_config_port,
1630 	.shutdown = qcom_geni_serial_shutdown,
1631 	.type = qcom_geni_serial_get_type,
1632 	.set_mctrl = qcom_geni_serial_set_mctrl,
1633 	.get_mctrl = qcom_geni_serial_get_mctrl,
1634 	.pm = qcom_geni_serial_pm,
1635 };
1636 
qcom_geni_serial_probe(struct platform_device * pdev)1637 static int qcom_geni_serial_probe(struct platform_device *pdev)
1638 {
1639 	int ret = 0;
1640 	int line;
1641 	struct qcom_geni_serial_port *port;
1642 	struct uart_port *uport;
1643 	struct resource *res;
1644 	int irq;
1645 	struct uart_driver *drv;
1646 	const struct qcom_geni_device_data *data;
1647 
1648 	data = of_device_get_match_data(&pdev->dev);
1649 	if (!data)
1650 		return -EINVAL;
1651 
1652 	if (data->console) {
1653 		drv = &qcom_geni_console_driver;
1654 		line = of_alias_get_id(pdev->dev.of_node, "serial");
1655 	} else {
1656 		drv = &qcom_geni_uart_driver;
1657 		line = of_alias_get_id(pdev->dev.of_node, "serial");
1658 		if (line == -ENODEV) /* compat with non-standard aliases */
1659 			line = of_alias_get_id(pdev->dev.of_node, "hsuart");
1660 	}
1661 
1662 	port = get_port_from_line(line, data->console);
1663 	if (IS_ERR(port)) {
1664 		dev_err(&pdev->dev, "Invalid line %d\n", line);
1665 		return PTR_ERR(port);
1666 	}
1667 
1668 	uport = &port->uport;
1669 	/* Don't allow 2 drivers to access the same port */
1670 	if (uport->private_data)
1671 		return -ENODEV;
1672 
1673 	uport->dev = &pdev->dev;
1674 	port->dev_data = data;
1675 	port->se.dev = &pdev->dev;
1676 	port->se.wrapper = dev_get_drvdata(pdev->dev.parent);
1677 	port->se.clk = devm_clk_get(&pdev->dev, "se");
1678 	if (IS_ERR(port->se.clk)) {
1679 		ret = PTR_ERR(port->se.clk);
1680 		dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret);
1681 		return ret;
1682 	}
1683 
1684 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1685 	if (!res)
1686 		return -EINVAL;
1687 	uport->mapbase = res->start;
1688 
1689 	port->tx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1690 	port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1691 	port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;
1692 
1693 	if (!data->console) {
1694 		port->rx_buf = devm_kzalloc(uport->dev,
1695 					    DMA_RX_BUF_SIZE, GFP_KERNEL);
1696 		if (!port->rx_buf)
1697 			return -ENOMEM;
1698 	}
1699 
1700 	ret = geni_icc_get(&port->se, NULL);
1701 	if (ret)
1702 		return ret;
1703 	port->se.icc_paths[GENI_TO_CORE].avg_bw = GENI_DEFAULT_BW;
1704 	port->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
1705 
1706 	/* Set BW for register access */
1707 	ret = geni_icc_set_bw(&port->se);
1708 	if (ret)
1709 		return ret;
1710 
1711 	port->name = devm_kasprintf(uport->dev, GFP_KERNEL,
1712 			"qcom_geni_serial_%s%d",
1713 			uart_console(uport) ? "console" : "uart", uport->line);
1714 	if (!port->name)
1715 		return -ENOMEM;
1716 
1717 	irq = platform_get_irq(pdev, 0);
1718 	if (irq < 0)
1719 		return irq;
1720 	uport->irq = irq;
1721 	uport->has_sysrq = IS_ENABLED(CONFIG_SERIAL_QCOM_GENI_CONSOLE);
1722 
1723 	if (!data->console)
1724 		port->wakeup_irq = platform_get_irq_optional(pdev, 1);
1725 
1726 	if (of_property_read_bool(pdev->dev.of_node, "rx-tx-swap"))
1727 		port->rx_tx_swap = true;
1728 
1729 	if (of_property_read_bool(pdev->dev.of_node, "cts-rts-swap"))
1730 		port->cts_rts_swap = true;
1731 
1732 	ret = devm_pm_opp_set_clkname(&pdev->dev, "se");
1733 	if (ret)
1734 		return ret;
1735 	/* OPP table is optional */
1736 	ret = devm_pm_opp_of_add_table(&pdev->dev);
1737 	if (ret && ret != -ENODEV) {
1738 		dev_err(&pdev->dev, "invalid OPP table in device tree\n");
1739 		return ret;
1740 	}
1741 
1742 	port->private_data.drv = drv;
1743 	uport->private_data = &port->private_data;
1744 	platform_set_drvdata(pdev, port);
1745 
1746 	irq_set_status_flags(uport->irq, IRQ_NOAUTOEN);
1747 	ret = devm_request_irq(uport->dev, uport->irq, qcom_geni_serial_isr,
1748 			IRQF_TRIGGER_HIGH, port->name, uport);
1749 	if (ret) {
1750 		dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret);
1751 		return ret;
1752 	}
1753 
1754 	ret = uart_add_one_port(drv, uport);
1755 	if (ret)
1756 		return ret;
1757 
1758 	if (port->wakeup_irq > 0) {
1759 		device_init_wakeup(&pdev->dev, true);
1760 		ret = dev_pm_set_dedicated_wake_irq(&pdev->dev,
1761 						port->wakeup_irq);
1762 		if (ret) {
1763 			device_init_wakeup(&pdev->dev, false);
1764 			uart_remove_one_port(drv, uport);
1765 			return ret;
1766 		}
1767 	}
1768 
1769 	return 0;
1770 }
1771 
qcom_geni_serial_remove(struct platform_device * pdev)1772 static void qcom_geni_serial_remove(struct platform_device *pdev)
1773 {
1774 	struct qcom_geni_serial_port *port = platform_get_drvdata(pdev);
1775 	struct uart_driver *drv = port->private_data.drv;
1776 
1777 	dev_pm_clear_wake_irq(&pdev->dev);
1778 	device_init_wakeup(&pdev->dev, false);
1779 	uart_remove_one_port(drv, &port->uport);
1780 }
1781 
qcom_geni_serial_suspend(struct device * dev)1782 static int qcom_geni_serial_suspend(struct device *dev)
1783 {
1784 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1785 	struct uart_port *uport = &port->uport;
1786 	struct qcom_geni_private_data *private_data = uport->private_data;
1787 
1788 	/*
1789 	 * This is done so we can hit the lowest possible state in suspend
1790 	 * even with no_console_suspend
1791 	 */
1792 	if (uart_console(uport)) {
1793 		geni_icc_set_tag(&port->se, QCOM_ICC_TAG_ACTIVE_ONLY);
1794 		geni_icc_set_bw(&port->se);
1795 	}
1796 	return uart_suspend_port(private_data->drv, uport);
1797 }
1798 
qcom_geni_serial_resume(struct device * dev)1799 static int qcom_geni_serial_resume(struct device *dev)
1800 {
1801 	int ret;
1802 	struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1803 	struct uart_port *uport = &port->uport;
1804 	struct qcom_geni_private_data *private_data = uport->private_data;
1805 
1806 	ret = uart_resume_port(private_data->drv, uport);
1807 	if (uart_console(uport)) {
1808 		geni_icc_set_tag(&port->se, QCOM_ICC_TAG_ALWAYS);
1809 		geni_icc_set_bw(&port->se);
1810 	}
1811 	return ret;
1812 }
1813 
1814 static const struct qcom_geni_device_data qcom_geni_console_data = {
1815 	.console = true,
1816 	.mode = GENI_SE_FIFO,
1817 };
1818 
1819 static const struct qcom_geni_device_data qcom_geni_uart_data = {
1820 	.console = false,
1821 	.mode = GENI_SE_DMA,
1822 };
1823 
1824 static const struct dev_pm_ops qcom_geni_serial_pm_ops = {
1825 	SYSTEM_SLEEP_PM_OPS(qcom_geni_serial_suspend, qcom_geni_serial_resume)
1826 };
1827 
1828 static const struct of_device_id qcom_geni_serial_match_table[] = {
1829 	{
1830 		.compatible = "qcom,geni-debug-uart",
1831 		.data = &qcom_geni_console_data,
1832 	},
1833 	{
1834 		.compatible = "qcom,geni-uart",
1835 		.data = &qcom_geni_uart_data,
1836 	},
1837 	{}
1838 };
1839 MODULE_DEVICE_TABLE(of, qcom_geni_serial_match_table);
1840 
1841 static struct platform_driver qcom_geni_serial_platform_driver = {
1842 	.remove = qcom_geni_serial_remove,
1843 	.probe = qcom_geni_serial_probe,
1844 	.driver = {
1845 		.name = "qcom_geni_serial",
1846 		.of_match_table = qcom_geni_serial_match_table,
1847 		.pm = &qcom_geni_serial_pm_ops,
1848 	},
1849 };
1850 
qcom_geni_serial_init(void)1851 static int __init qcom_geni_serial_init(void)
1852 {
1853 	int ret;
1854 
1855 	ret = console_register(&qcom_geni_console_driver);
1856 	if (ret)
1857 		return ret;
1858 
1859 	ret = uart_register_driver(&qcom_geni_uart_driver);
1860 	if (ret) {
1861 		console_unregister(&qcom_geni_console_driver);
1862 		return ret;
1863 	}
1864 
1865 	ret = platform_driver_register(&qcom_geni_serial_platform_driver);
1866 	if (ret) {
1867 		console_unregister(&qcom_geni_console_driver);
1868 		uart_unregister_driver(&qcom_geni_uart_driver);
1869 	}
1870 	return ret;
1871 }
1872 module_init(qcom_geni_serial_init);
1873 
qcom_geni_serial_exit(void)1874 static void __exit qcom_geni_serial_exit(void)
1875 {
1876 	platform_driver_unregister(&qcom_geni_serial_platform_driver);
1877 	console_unregister(&qcom_geni_console_driver);
1878 	uart_unregister_driver(&qcom_geni_uart_driver);
1879 }
1880 module_exit(qcom_geni_serial_exit);
1881 
1882 MODULE_DESCRIPTION("Serial driver for GENI based QUP cores");
1883 MODULE_LICENSE("GPL v2");
1884