1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Qualcomm GENI serial engine UART driver
4  *
5  * (C) Copyright 2021 Dzmitry Sankouski <dsankouski@gmail.com>
6  *
7  * Based on Linux driver.
8  */
9 
10 #include <asm/io.h>
11 #include <clk.h>
12 #include <common.h>
13 #include <dm.h>
14 #include <dm/pinctrl.h>
15 #include <errno.h>
16 #include <linux/compiler.h>
17 #include <log.h>
18 #include <linux/delay.h>
19 #include <malloc.h>
20 #include <serial.h>
21 #include <watchdog.h>
22 #include <linux/bug.h>
23 
24 #define UART_OVERSAMPLING	32
25 #define STALE_TIMEOUT	160
26 
27 #define USEC_PER_SEC	1000000L
28 
29 /* Registers*/
30 #define GENI_FORCE_DEFAULT_REG	0x20
31 #define GENI_SER_M_CLK_CFG	0x48
32 #define GENI_SER_S_CLK_CFG	0x4C
33 #define SE_HW_PARAM_0	0xE24
34 #define SE_GENI_STATUS	0x40
35 #define SE_GENI_S_CMD0	0x630
36 #define SE_GENI_S_CMD_CTRL_REG	0x634
37 #define SE_GENI_S_IRQ_CLEAR	0x648
38 #define SE_GENI_S_IRQ_STATUS	0x640
39 #define SE_GENI_S_IRQ_EN	0x644
40 #define SE_GENI_M_CMD0	0x600
41 #define SE_GENI_M_CMD_CTRL_REG	0x604
42 #define SE_GENI_M_IRQ_CLEAR	0x618
43 #define SE_GENI_M_IRQ_STATUS	0x610
44 #define SE_GENI_M_IRQ_EN	0x614
45 #define SE_GENI_TX_FIFOn	0x700
46 #define SE_GENI_RX_FIFOn	0x780
47 #define SE_GENI_TX_FIFO_STATUS	0x800
48 #define SE_GENI_RX_FIFO_STATUS	0x804
49 #define SE_GENI_TX_WATERMARK_REG	0x80C
50 #define SE_GENI_TX_PACKING_CFG0	0x260
51 #define SE_GENI_TX_PACKING_CFG1	0x264
52 #define SE_GENI_RX_PACKING_CFG0	0x284
53 #define SE_GENI_RX_PACKING_CFG1	0x288
54 #define SE_UART_RX_STALE_CNT	0x294
55 #define SE_UART_TX_TRANS_LEN	0x270
56 #define SE_UART_TX_STOP_BIT_LEN	0x26c
57 #define SE_UART_TX_WORD_LEN	0x268
58 #define SE_UART_RX_WORD_LEN	0x28c
59 #define SE_UART_TX_TRANS_CFG	0x25c
60 #define SE_UART_TX_PARITY_CFG	0x2a4
61 #define SE_UART_RX_TRANS_CFG	0x280
62 #define SE_UART_RX_PARITY_CFG	0x2a8
63 
64 #define M_TX_FIFO_WATERMARK_EN	(BIT(30))
65 #define DEF_TX_WM	2
66 /* GENI_FORCE_DEFAULT_REG fields */
67 #define FORCE_DEFAULT	(BIT(0))
68 
69 #define S_CMD_ABORT_EN	(BIT(5))
70 
71 #define UART_START_READ	0x1
72 
73 /* GENI_M_CMD_CTRL_REG */
74 #define M_GENI_CMD_CANCEL	(BIT(2))
75 #define M_GENI_CMD_ABORT	(BIT(1))
76 #define M_GENI_DISABLE	(BIT(0))
77 
78 #define M_CMD_ABORT_EN	(BIT(5))
79 #define M_CMD_DONE_EN	(BIT(0))
80 #define M_CMD_DONE_DISABLE_MASK	(~M_CMD_DONE_EN)
81 
82 #define S_GENI_CMD_ABORT	(BIT(1))
83 
84 /* GENI_S_CMD0 fields */
85 #define S_OPCODE_MSK	(GENMASK(31, 27))
86 #define S_PARAMS_MSK	(GENMASK(26, 0))
87 
88 /* GENI_STATUS fields */
89 #define M_GENI_CMD_ACTIVE	(BIT(0))
90 #define S_GENI_CMD_ACTIVE	(BIT(12))
91 #define M_CMD_DONE_EN	(BIT(0))
92 #define S_CMD_DONE_EN	(BIT(0))
93 
94 #define M_OPCODE_SHIFT	27
95 #define S_OPCODE_SHIFT	27
96 #define M_TX_FIFO_WATERMARK_EN	(BIT(30))
97 #define UART_START_TX	0x1
98 #define UART_CTS_MASK	(BIT(1))
99 #define M_SEC_IRQ_EN	(BIT(31))
100 #define TX_FIFO_WC_MSK	(GENMASK(27, 0))
101 #define RX_FIFO_WC_MSK	(GENMASK(24, 0))
102 
103 #define S_RX_FIFO_WATERMARK_EN	(BIT(26))
104 #define S_RX_FIFO_LAST_EN	(BIT(27))
105 #define M_RX_FIFO_WATERMARK_EN	(BIT(26))
106 #define M_RX_FIFO_LAST_EN	(BIT(27))
107 
108 /* GENI_SER_M_CLK_CFG/GENI_SER_S_CLK_CFG */
109 #define SER_CLK_EN	(BIT(0))
110 #define CLK_DIV_MSK	(GENMASK(15, 4))
111 #define CLK_DIV_SHFT	4
112 
113 /* SE_HW_PARAM_0 fields */
114 #define TX_FIFO_WIDTH_MSK	(GENMASK(29, 24))
115 #define TX_FIFO_WIDTH_SHFT	24
116 #define TX_FIFO_DEPTH_MSK	(GENMASK(21, 16))
117 #define TX_FIFO_DEPTH_SHFT	16
118 
119 /*
120  * Predefined packing configuration of the serial engine (CFG0, CFG1 regs)
121  * for uart mode.
122  *
123  * Defines following configuration:
124  * - Bits of data per transfer word             8
125  * - Number of words per fifo element           4
126  * - Transfer from MSB to LSB or vice-versa     false
127  */
128 #define UART_PACKING_CFG0   0xf
129 #define UART_PACKING_CFG1   0x0
130 
131 DECLARE_GLOBAL_DATA_PTR;
132 
133 struct msm_serial_data {
134 	phys_addr_t base;
135 	u32 baud;
136 };
137 
138 unsigned long root_freq[] = {7372800,  14745600, 19200000, 29491200,
139 					 32000000, 48000000, 64000000, 80000000,
140 					 96000000, 100000000};
141 
142 /**
143  * get_clk_cfg() - Get clock rate to apply on clock supplier.
144  * @clk_freq:	Desired clock frequency after build-in divider.
145  *
146  * Return: frequency, supported by clock supplier, multiple of clk_freq.
147  */
get_clk_cfg(unsigned long clk_freq)148 static int get_clk_cfg(unsigned long clk_freq)
149 {
150 	for (int i = 0; i < ARRAY_SIZE(root_freq); i++) {
151 		if (!(root_freq[i] % clk_freq))
152 			return root_freq[i];
153 	}
154 	return 0;
155 }
156 
157 /**
158  * get_clk_div_rate() - Find clock supplier frequency, and calculate divisor.
159  * @baud:	        Baudrate.
160  * @sampling_rate:	Clock ticks per character.
161  * @clk_div:	    Pointer to calculated divisor.
162  *
163  * This function searches for suitable frequency for clock supplier,
164  * calculates divisor for internal divider, based on found frequency,
165  * and stores divisor under clk_div pointer.
166  *
167  * Return: frequency, supported by clock supplier, multiple of clk_freq.
168  */
get_clk_div_rate(u32 baud,u64 sampling_rate,u32 * clk_div)169 static int get_clk_div_rate(u32 baud,
170 							u64 sampling_rate, u32 *clk_div)
171 {
172 	unsigned long ser_clk;
173 	unsigned long desired_clk;
174 
175 	desired_clk = baud * sampling_rate;
176 	ser_clk = get_clk_cfg(desired_clk);
177 	if (!ser_clk) {
178 		pr_err("%s: Can't find matching DFS entry for baud %d\n",
179 								__func__, baud);
180 		return ser_clk;
181 	}
182 
183 	*clk_div = ser_clk / desired_clk;
184 	return ser_clk;
185 }
186 
geni_serial_set_clock_rate(struct udevice * dev,u64 rate)187 static int geni_serial_set_clock_rate(struct udevice *dev, u64 rate)
188 {
189 	struct clk *clk;
190 	int ret;
191 
192 	clk = devm_clk_get(dev, "se-clk");
193 	if (!clk)
194 		return -EINVAL;
195 
196 	ret = clk_set_rate(clk, rate);
197 	return ret;
198 }
199 
200 /**
201  * geni_se_get_tx_fifo_depth() - Get the TX fifo depth of the serial engine
202  * @base:	Pointer to the concerned serial engine.
203  *
204  * This function is used to get the depth i.e. number of elements in the
205  * TX fifo of the serial engine.
206  *
207  * Return: TX fifo depth in units of FIFO words.
208  */
geni_se_get_tx_fifo_depth(long base)209 static inline u32 geni_se_get_tx_fifo_depth(long base)
210 {
211 	u32 tx_fifo_depth;
212 
213 	tx_fifo_depth = ((readl(base + SE_HW_PARAM_0) & TX_FIFO_DEPTH_MSK) >>
214 			 TX_FIFO_DEPTH_SHFT);
215 	return tx_fifo_depth;
216 }
217 
218 /**
219  * geni_se_get_tx_fifo_width() - Get the TX fifo width of the serial engine
220  * @base:	Pointer to the concerned serial engine.
221  *
222  * This function is used to get the width i.e. word size per element in the
223  * TX fifo of the serial engine.
224  *
225  * Return: TX fifo width in bits
226  */
geni_se_get_tx_fifo_width(long base)227 static inline u32 geni_se_get_tx_fifo_width(long base)
228 {
229 	u32 tx_fifo_width;
230 
231 	tx_fifo_width = ((readl(base + SE_HW_PARAM_0) & TX_FIFO_WIDTH_MSK) >>
232 			 TX_FIFO_WIDTH_SHFT);
233 	return tx_fifo_width;
234 }
235 
geni_serial_baud(phys_addr_t base_address,u32 clk_div,int baud)236 static inline void geni_serial_baud(phys_addr_t base_address, u32 clk_div,
237 									int baud)
238 {
239 	u32 s_clk_cfg = 0;
240 
241 	s_clk_cfg |= SER_CLK_EN;
242 	s_clk_cfg |= (clk_div << CLK_DIV_SHFT);
243 
244 	writel(s_clk_cfg, base_address + GENI_SER_M_CLK_CFG);
245 	writel(s_clk_cfg, base_address + GENI_SER_S_CLK_CFG);
246 }
247 
msm_serial_setbrg(struct udevice * dev,int baud)248 int msm_serial_setbrg(struct udevice *dev, int baud)
249 {
250 	struct msm_serial_data *priv = dev_get_priv(dev);
251 
252 	priv->baud = baud;
253 	u32 clk_div;
254 	u64 clk_rate;
255 
256 	clk_rate = get_clk_div_rate(baud, UART_OVERSAMPLING, &clk_div);
257 	geni_serial_set_clock_rate(dev, clk_rate);
258 	geni_serial_baud(priv->base, clk_div, baud);
259 
260 	return 0;
261 }
262 
263 /**
264  * qcom_geni_serial_poll_bit() - Poll reg bit until desired value or timeout.
265  * @base:	Pointer to the concerned serial engine.
266  * @offset:	Offset to register address.
267  * @field:	AND bitmask for desired bit.
268  * @set:	Desired bit value.
269  *
270  * This function is used to get the width i.e. word size per element in the
271  * TX fifo of the serial engine.
272  *
273  * Return: true, when register bit equals desired value, false, when timeout
274  * reached.
275  */
qcom_geni_serial_poll_bit(const struct udevice * dev,int offset,int field,bool set)276 static bool qcom_geni_serial_poll_bit(const struct udevice *dev, int offset,
277 					  int field, bool set)
278 {
279 	u32 reg;
280 	struct msm_serial_data *priv = dev_get_priv(dev);
281 	unsigned int baud;
282 	unsigned int tx_fifo_depth;
283 	unsigned int tx_fifo_width;
284 	unsigned int fifo_bits;
285 	unsigned long timeout_us = 10000;
286 
287 	baud = 115200;
288 
289 	if (priv) {
290 		baud = priv->baud;
291 		if (!baud)
292 			baud = 115200;
293 		tx_fifo_depth = geni_se_get_tx_fifo_depth(priv->base);
294 		tx_fifo_width = geni_se_get_tx_fifo_width(priv->base);
295 		fifo_bits = tx_fifo_depth * tx_fifo_width;
296 		/*
297 		 * Total polling iterations based on FIFO worth of bytes to be
298 		 * sent at current baud. Add a little fluff to the wait.
299 		 */
300 		timeout_us = ((fifo_bits * USEC_PER_SEC) / baud) + 500;
301 	}
302 
303 	timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10;
304 	while (timeout_us) {
305 		reg = readl(priv->base + offset);
306 		if ((bool)(reg & field) == set)
307 			return true;
308 		udelay(10);
309 		timeout_us -= 10;
310 	}
311 	return false;
312 }
313 
qcom_geni_serial_setup_tx(u64 base,u32 xmit_size)314 static void qcom_geni_serial_setup_tx(u64 base, u32 xmit_size)
315 {
316 	u32 m_cmd;
317 
318 	writel(xmit_size, base + SE_UART_TX_TRANS_LEN);
319 	m_cmd = UART_START_TX << M_OPCODE_SHIFT;
320 	writel(m_cmd, base + SE_GENI_M_CMD0);
321 }
322 
qcom_geni_serial_poll_tx_done(const struct udevice * dev)323 static inline void qcom_geni_serial_poll_tx_done(const struct udevice *dev)
324 {
325 	struct msm_serial_data *priv = dev_get_priv(dev);
326 	int done = 0;
327 	u32 irq_clear = M_CMD_DONE_EN;
328 
329 	done = qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS,
330 					 M_CMD_DONE_EN, true);
331 	if (!done) {
332 		writel(M_GENI_CMD_ABORT, priv->base + SE_GENI_M_CMD_CTRL_REG);
333 		irq_clear |= M_CMD_ABORT_EN;
334 		qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS,
335 					  M_CMD_ABORT_EN, true);
336 	}
337 	writel(irq_clear, priv->base + SE_GENI_M_IRQ_CLEAR);
338 }
339 
qcom_geni_serial_tx_empty(u64 base)340 static u32 qcom_geni_serial_tx_empty(u64 base)
341 {
342 	return !readl(base + SE_GENI_TX_FIFO_STATUS);
343 }
344 
345 /**
346  * geni_se_setup_s_cmd() - Setup the secondary sequencer
347  * @se:		Pointer to the concerned serial engine.
348  * @cmd:	Command/Operation to setup in the secondary sequencer.
349  * @params:	Parameter for the sequencer command.
350  *
351  * This function is used to configure the secondary sequencer with the
352  * command and its associated parameters.
353  */
geni_se_setup_s_cmd(u64 base,u32 cmd,u32 params)354 static inline void geni_se_setup_s_cmd(u64 base, u32 cmd, u32 params)
355 {
356 	u32 s_cmd;
357 
358 	s_cmd = readl(base + SE_GENI_S_CMD0);
359 	s_cmd &= ~(S_OPCODE_MSK | S_PARAMS_MSK);
360 	s_cmd |= (cmd << S_OPCODE_SHIFT);
361 	s_cmd |= (params & S_PARAMS_MSK);
362 	writel(s_cmd, base + SE_GENI_S_CMD0);
363 }
364 
qcom_geni_serial_start_tx(u64 base)365 static void qcom_geni_serial_start_tx(u64 base)
366 {
367 	u32 irq_en;
368 	u32 status;
369 
370 	status = readl(base + SE_GENI_STATUS);
371 	if (status & M_GENI_CMD_ACTIVE)
372 		return;
373 
374 	if (!qcom_geni_serial_tx_empty(base))
375 		return;
376 
377 	irq_en = readl(base + SE_GENI_M_IRQ_EN);
378 	irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
379 
380 	writel(DEF_TX_WM, base + SE_GENI_TX_WATERMARK_REG);
381 	writel(irq_en, base + SE_GENI_M_IRQ_EN);
382 }
383 
qcom_geni_serial_start_rx(struct udevice * dev)384 static void qcom_geni_serial_start_rx(struct udevice *dev)
385 {
386 	u32 status;
387 	struct msm_serial_data *priv = dev_get_priv(dev);
388 
389 	status = readl(priv->base + SE_GENI_STATUS);
390 
391 	geni_se_setup_s_cmd(priv->base, UART_START_READ, 0);
392 
393 	setbits_le32(priv->base + SE_GENI_S_IRQ_EN, S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN);
394 	setbits_le32(priv->base + SE_GENI_M_IRQ_EN, M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
395 }
396 
qcom_geni_serial_abort_rx(struct udevice * dev)397 static void qcom_geni_serial_abort_rx(struct udevice *dev)
398 {
399 	struct msm_serial_data *priv = dev_get_priv(dev);
400 
401 	u32 irq_clear = S_CMD_DONE_EN | S_CMD_ABORT_EN;
402 
403 	writel(S_GENI_CMD_ABORT, priv->base + SE_GENI_S_CMD_CTRL_REG);
404 	qcom_geni_serial_poll_bit(dev, SE_GENI_S_CMD_CTRL_REG,
405 					S_GENI_CMD_ABORT, false);
406 	writel(irq_clear, priv->base + SE_GENI_S_IRQ_CLEAR);
407 	writel(FORCE_DEFAULT, priv->base + GENI_FORCE_DEFAULT_REG);
408 }
409 
msm_geni_serial_setup_rx(struct udevice * dev)410 static void msm_geni_serial_setup_rx(struct udevice *dev)
411 {
412 	struct msm_serial_data *priv = dev_get_priv(dev);
413 
414 	qcom_geni_serial_abort_rx(dev);
415 
416 	writel(UART_PACKING_CFG0, priv->base + SE_GENI_RX_PACKING_CFG0);
417 	writel(UART_PACKING_CFG1, priv->base + SE_GENI_RX_PACKING_CFG1);
418 
419 	geni_se_setup_s_cmd(priv->base, UART_START_READ, 0);
420 
421 	setbits_le32(priv->base + SE_GENI_S_IRQ_EN, S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN);
422 	setbits_le32(priv->base + SE_GENI_M_IRQ_EN, M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
423 }
424 
msm_serial_putc(struct udevice * dev,const char ch)425 static int msm_serial_putc(struct udevice *dev, const char ch)
426 {
427 	struct msm_serial_data *priv = dev_get_priv(dev);
428 
429 	writel(DEF_TX_WM, priv->base + SE_GENI_TX_WATERMARK_REG);
430 	qcom_geni_serial_setup_tx(priv->base, 1);
431 
432 	qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS,
433 				  M_TX_FIFO_WATERMARK_EN, true);
434 
435 	writel(ch, priv->base + SE_GENI_TX_FIFOn);
436 	writel(M_TX_FIFO_WATERMARK_EN, priv->base + SE_GENI_M_IRQ_CLEAR);
437 
438 	qcom_geni_serial_poll_tx_done(dev);
439 
440 	return 0;
441 }
442 
msm_serial_getc(struct udevice * dev)443 static int msm_serial_getc(struct udevice *dev)
444 {
445 	struct msm_serial_data *priv = dev_get_priv(dev);
446 	u32 rx_fifo;
447 	u32 m_irq_status;
448 	u32 s_irq_status;
449 
450 	writel(1 << S_OPCODE_SHIFT, priv->base + SE_GENI_S_CMD0);
451 
452 	qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS, M_SEC_IRQ_EN,
453 				  true);
454 
455 	m_irq_status = readl(priv->base + SE_GENI_M_IRQ_STATUS);
456 	s_irq_status = readl(priv->base + SE_GENI_S_IRQ_STATUS);
457 	writel(m_irq_status, priv->base + SE_GENI_M_IRQ_CLEAR);
458 	writel(s_irq_status, priv->base + SE_GENI_S_IRQ_CLEAR);
459 	qcom_geni_serial_poll_bit(dev, SE_GENI_RX_FIFO_STATUS, RX_FIFO_WC_MSK,
460 				  true);
461 
462 	if (!readl(priv->base + SE_GENI_RX_FIFO_STATUS))
463 		return 0;
464 
465 	rx_fifo = readl(priv->base + SE_GENI_RX_FIFOn);
466 	return rx_fifo & 0xff;
467 }
468 
msm_serial_pending(struct udevice * dev,bool input)469 static int msm_serial_pending(struct udevice *dev, bool input)
470 {
471 	struct msm_serial_data *priv = dev_get_priv(dev);
472 
473 	if (input)
474 		return readl(priv->base + SE_GENI_RX_FIFO_STATUS) &
475 			   RX_FIFO_WC_MSK;
476 	else
477 		return readl(priv->base + SE_GENI_TX_FIFO_STATUS) &
478 			   TX_FIFO_WC_MSK;
479 
480 	return 0;
481 }
482 
483 static const struct dm_serial_ops msm_serial_ops = {
484 	.putc = msm_serial_putc,
485 	.pending = msm_serial_pending,
486 	.getc = msm_serial_getc,
487 	.setbrg = msm_serial_setbrg,
488 };
489 
geni_serial_init(struct udevice * dev)490 static inline void geni_serial_init(struct udevice *dev)
491 {
492 	struct msm_serial_data *priv = dev_get_priv(dev);
493 	phys_addr_t base_address = priv->base;
494 	u32 tx_trans_cfg;
495 	u32 tx_parity_cfg = 0; /* Disable Tx Parity */
496 	u32 rx_trans_cfg = 0;
497 	u32 rx_parity_cfg = 0; /* Disable Rx Parity */
498 	u32 stop_bit_len = 0;  /* Default stop bit length - 1 bit */
499 	u32 bits_per_char;
500 
501 	/*
502 	 * Ignore Flow control.
503 	 * n = 8.
504 	 */
505 	tx_trans_cfg = UART_CTS_MASK;
506 	bits_per_char = BITS_PER_BYTE;
507 
508 	/*
509 	 * Make an unconditional cancel on the main sequencer to reset
510 	 * it else we could end up in data loss scenarios.
511 	 */
512 	qcom_geni_serial_poll_tx_done(dev);
513 	qcom_geni_serial_abort_rx(dev);
514 
515 	writel(UART_PACKING_CFG0, base_address + SE_GENI_TX_PACKING_CFG0);
516 	writel(UART_PACKING_CFG1, base_address + SE_GENI_TX_PACKING_CFG1);
517 	writel(UART_PACKING_CFG0, base_address + SE_GENI_RX_PACKING_CFG0);
518 	writel(UART_PACKING_CFG1, base_address + SE_GENI_RX_PACKING_CFG1);
519 
520 	writel(tx_trans_cfg, base_address + SE_UART_TX_TRANS_CFG);
521 	writel(tx_parity_cfg, base_address + SE_UART_TX_PARITY_CFG);
522 	writel(rx_trans_cfg, base_address + SE_UART_RX_TRANS_CFG);
523 	writel(rx_parity_cfg, base_address + SE_UART_RX_PARITY_CFG);
524 	writel(bits_per_char, base_address + SE_UART_TX_WORD_LEN);
525 	writel(bits_per_char, base_address + SE_UART_RX_WORD_LEN);
526 	writel(stop_bit_len, base_address + SE_UART_TX_STOP_BIT_LEN);
527 }
528 
msm_serial_probe(struct udevice * dev)529 static int msm_serial_probe(struct udevice *dev)
530 {
531 	struct msm_serial_data *priv = dev_get_priv(dev);
532 
533 	/* No need to reinitialize the UART after relocation */
534 	if (gd->flags & GD_FLG_RELOC)
535 		return 0;
536 
537 	geni_serial_init(dev);
538 	msm_geni_serial_setup_rx(dev);
539 	qcom_geni_serial_start_rx(dev);
540 	qcom_geni_serial_start_tx(priv->base);
541 
542 	return 0;
543 }
544 
msm_serial_ofdata_to_platdata(struct udevice * dev)545 static int msm_serial_ofdata_to_platdata(struct udevice *dev)
546 {
547 	struct msm_serial_data *priv = dev_get_priv(dev);
548 
549 	priv->base = dev_read_addr(dev);
550 	if (priv->base == FDT_ADDR_T_NONE)
551 		return -EINVAL;
552 
553 	return 0;
554 }
555 
556 static const struct udevice_id msm_serial_ids[] = {
557 	{.compatible = "qcom,msm-geni-uart"}, {}};
558 
559 U_BOOT_DRIVER(serial_msm_geni) = {
560 	.name = "serial_msm_geni",
561 	.id = UCLASS_SERIAL,
562 	.of_match = msm_serial_ids,
563 	.of_to_plat = msm_serial_ofdata_to_platdata,
564 	.priv_auto = sizeof(struct msm_serial_data),
565 	.probe = msm_serial_probe,
566 	.ops = &msm_serial_ops,
567 };
568 
569 #ifdef CONFIG_DEBUG_UART_MSM_GENI
570 
571 static struct msm_serial_data init_serial_data = {
572 	.base = CONFIG_DEBUG_UART_BASE
573 };
574 
575 /* Serial dumb device, to reuse driver code */
576 static struct udevice init_dev = {
577 	.priv_ = &init_serial_data,
578 };
579 
580 #include <debug_uart.h>
581 
582 #define CLK_DIV (CONFIG_DEBUG_UART_CLOCK / \
583 					(CONFIG_BAUDRATE * UART_OVERSAMPLING))
584 #if (CONFIG_DEBUG_UART_CLOCK % (CONFIG_BAUDRATE * UART_OVERSAMPLING) > 0)
585 #error Clocks cannot be set at early debug. Change CONFIG_BAUDRATE
586 #endif
587 
_debug_uart_init(void)588 static inline void _debug_uart_init(void)
589 {
590 	phys_addr_t base = CONFIG_DEBUG_UART_BASE;
591 
592 	geni_serial_init(&init_dev);
593 	geni_serial_baud(base, CLK_DIV, CONFIG_BAUDRATE);
594 	qcom_geni_serial_start_tx(base);
595 }
596 
_debug_uart_putc(int ch)597 static inline void _debug_uart_putc(int ch)
598 {
599 	phys_addr_t base = CONFIG_DEBUG_UART_BASE;
600 
601 	writel(DEF_TX_WM, base + SE_GENI_TX_WATERMARK_REG);
602 	qcom_geni_serial_setup_tx(base, 1);
603 	qcom_geni_serial_poll_bit(&init_dev, SE_GENI_M_IRQ_STATUS,
604 				  M_TX_FIFO_WATERMARK_EN, true);
605 
606 	writel(ch, base + SE_GENI_TX_FIFOn);
607 	writel(M_TX_FIFO_WATERMARK_EN, base + SE_GENI_M_IRQ_CLEAR);
608 	qcom_geni_serial_poll_tx_done(&init_dev);
609 }
610 
611 DEBUG_UART_FUNCS
612 
613 #endif
614