1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux foundation. All rights reserved.
3
4 #include <linux/clk.h>
5 #include <linux/console.h>
6 #include <linux/io.h>
7 #include <linux/iopoll.h>
8 #include <linux/module.h>
9 #include <linux/of.h>
10 #include <linux/of_device.h>
11 #include <linux/platform_device.h>
12 #include <linux/qcom-geni-se.h>
13 #include <linux/serial.h>
14 #include <linux/serial_core.h>
15 #include <linux/slab.h>
16 #include <linux/tty.h>
17 #include <linux/tty_flip.h>
18
19 /* UART specific GENI registers */
20 #define SE_UART_LOOPBACK_CFG 0x22c
21 #define SE_UART_TX_TRANS_CFG 0x25c
22 #define SE_UART_TX_WORD_LEN 0x268
23 #define SE_UART_TX_STOP_BIT_LEN 0x26c
24 #define SE_UART_TX_TRANS_LEN 0x270
25 #define SE_UART_RX_TRANS_CFG 0x280
26 #define SE_UART_RX_WORD_LEN 0x28c
27 #define SE_UART_RX_STALE_CNT 0x294
28 #define SE_UART_TX_PARITY_CFG 0x2a4
29 #define SE_UART_RX_PARITY_CFG 0x2a8
30 #define SE_UART_MANUAL_RFR 0x2ac
31
32 /* SE_UART_TRANS_CFG */
33 #define UART_TX_PAR_EN BIT(0)
34 #define UART_CTS_MASK BIT(1)
35
36 /* SE_UART_TX_WORD_LEN */
37 #define TX_WORD_LEN_MSK GENMASK(9, 0)
38
39 /* SE_UART_TX_STOP_BIT_LEN */
40 #define TX_STOP_BIT_LEN_MSK GENMASK(23, 0)
41 #define TX_STOP_BIT_LEN_1 0
42 #define TX_STOP_BIT_LEN_1_5 1
43 #define TX_STOP_BIT_LEN_2 2
44
45 /* SE_UART_TX_TRANS_LEN */
46 #define TX_TRANS_LEN_MSK GENMASK(23, 0)
47
48 /* SE_UART_RX_TRANS_CFG */
49 #define UART_RX_INS_STATUS_BIT BIT(2)
50 #define UART_RX_PAR_EN BIT(3)
51
52 /* SE_UART_RX_WORD_LEN */
53 #define RX_WORD_LEN_MASK GENMASK(9, 0)
54
55 /* SE_UART_RX_STALE_CNT */
56 #define RX_STALE_CNT GENMASK(23, 0)
57
58 /* SE_UART_TX_PARITY_CFG/RX_PARITY_CFG */
59 #define PAR_CALC_EN BIT(0)
60 #define PAR_MODE_MSK GENMASK(2, 1)
61 #define PAR_MODE_SHFT 1
62 #define PAR_EVEN 0x00
63 #define PAR_ODD 0x01
64 #define PAR_SPACE 0x10
65 #define PAR_MARK 0x11
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 #define UART_START_BREAK 0x4
75 #define UART_STOP_BREAK 0x5
76 /* UART S_CMD OP codes */
77 #define UART_START_READ 0x1
78 #define UART_PARAM 0x1
79
80 #define UART_OVERSAMPLING 32
81 #define STALE_TIMEOUT 16
82 #define DEFAULT_BITS_PER_CHAR 10
83 #define GENI_UART_CONS_PORTS 1
84 #define GENI_UART_PORTS 3
85 #define DEF_FIFO_DEPTH_WORDS 16
86 #define DEF_TX_WM 2
87 #define DEF_FIFO_WIDTH_BITS 32
88 #define UART_CONSOLE_RX_WM 2
89 #define MAX_LOOPBACK_CFG 3
90
91 #ifdef CONFIG_CONSOLE_POLL
92 #define RX_BYTES_PW 1
93 #else
94 #define RX_BYTES_PW 4
95 #endif
96
97 struct qcom_geni_serial_port {
98 struct uart_port uport;
99 struct geni_se se;
100 char name[20];
101 u32 tx_fifo_depth;
102 u32 tx_fifo_width;
103 u32 rx_fifo_depth;
104 u32 tx_wm;
105 u32 rx_wm;
106 u32 rx_rfr;
107 enum geni_se_xfer_mode xfer_mode;
108 bool setup;
109 int (*handle_rx)(struct uart_port *uport, u32 bytes, bool drop);
110 unsigned int baud;
111 unsigned int tx_bytes_pw;
112 unsigned int rx_bytes_pw;
113 u32 *rx_fifo;
114 u32 loopback;
115 bool brk;
116 };
117
118 static const struct uart_ops qcom_geni_console_pops;
119 static const struct uart_ops qcom_geni_uart_pops;
120 static struct uart_driver qcom_geni_console_driver;
121 static struct uart_driver qcom_geni_uart_driver;
122 static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop);
123 static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop);
124 static unsigned int qcom_geni_serial_tx_empty(struct uart_port *port);
125 static void qcom_geni_serial_stop_rx(struct uart_port *uport);
126
127 static const unsigned long root_freq[] = {7372800, 14745600, 19200000, 29491200,
128 32000000, 48000000, 64000000, 80000000,
129 96000000, 100000000, 102400000,
130 112000000, 120000000, 128000000};
131
132 #define to_dev_port(ptr, member) \
133 container_of(ptr, struct qcom_geni_serial_port, member)
134
135 static struct qcom_geni_serial_port qcom_geni_uart_ports[GENI_UART_PORTS] = {
136 [0] = {
137 .uport = {
138 .iotype = UPIO_MEM,
139 .ops = &qcom_geni_uart_pops,
140 .flags = UPF_BOOT_AUTOCONF,
141 .line = 0,
142 },
143 },
144 [1] = {
145 .uport = {
146 .iotype = UPIO_MEM,
147 .ops = &qcom_geni_uart_pops,
148 .flags = UPF_BOOT_AUTOCONF,
149 .line = 1,
150 },
151 },
152 [2] = {
153 .uport = {
154 .iotype = UPIO_MEM,
155 .ops = &qcom_geni_uart_pops,
156 .flags = UPF_BOOT_AUTOCONF,
157 .line = 2,
158 },
159 },
160 };
161
loopback_show(struct device * dev,struct device_attribute * attr,char * buf)162 static ssize_t loopback_show(struct device *dev,
163 struct device_attribute *attr, char *buf)
164 {
165 struct platform_device *pdev = to_platform_device(dev);
166 struct qcom_geni_serial_port *port = platform_get_drvdata(pdev);
167
168 return snprintf(buf, sizeof(u32), "%d\n", port->loopback);
169 }
170
loopback_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)171 static ssize_t loopback_store(struct device *dev,
172 struct device_attribute *attr, const char *buf,
173 size_t size)
174 {
175 struct platform_device *pdev = to_platform_device(dev);
176 struct qcom_geni_serial_port *port = platform_get_drvdata(pdev);
177 u32 loopback;
178
179 if (kstrtoint(buf, 0, &loopback) || loopback > MAX_LOOPBACK_CFG) {
180 dev_err(dev, "Invalid input\n");
181 return -EINVAL;
182 }
183 port->loopback = loopback;
184 return size;
185 }
186 static DEVICE_ATTR_RW(loopback);
187
188 static struct qcom_geni_serial_port qcom_geni_console_port = {
189 .uport = {
190 .iotype = UPIO_MEM,
191 .ops = &qcom_geni_console_pops,
192 .flags = UPF_BOOT_AUTOCONF,
193 .line = 0,
194 },
195 };
196
qcom_geni_serial_request_port(struct uart_port * uport)197 static int qcom_geni_serial_request_port(struct uart_port *uport)
198 {
199 struct platform_device *pdev = to_platform_device(uport->dev);
200 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
201 struct resource *res;
202
203 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
204 uport->membase = devm_ioremap_resource(&pdev->dev, res);
205 if (IS_ERR(uport->membase))
206 return PTR_ERR(uport->membase);
207 port->se.base = uport->membase;
208 return 0;
209 }
210
qcom_geni_serial_config_port(struct uart_port * uport,int cfg_flags)211 static void qcom_geni_serial_config_port(struct uart_port *uport, int cfg_flags)
212 {
213 if (cfg_flags & UART_CONFIG_TYPE) {
214 uport->type = PORT_MSM;
215 qcom_geni_serial_request_port(uport);
216 }
217 }
218
qcom_geni_serial_get_mctrl(struct uart_port * uport)219 static unsigned int qcom_geni_serial_get_mctrl(struct uart_port *uport)
220 {
221 unsigned int mctrl = TIOCM_DSR | TIOCM_CAR;
222 u32 geni_ios;
223
224 if (uart_console(uport) || !uart_cts_enabled(uport)) {
225 mctrl |= TIOCM_CTS;
226 } else {
227 geni_ios = readl_relaxed(uport->membase + SE_GENI_IOS);
228 if (!(geni_ios & IO2_DATA_IN))
229 mctrl |= TIOCM_CTS;
230 }
231
232 return mctrl;
233 }
234
qcom_geni_serial_set_mctrl(struct uart_port * uport,unsigned int mctrl)235 static void qcom_geni_serial_set_mctrl(struct uart_port *uport,
236 unsigned int mctrl)
237 {
238 u32 uart_manual_rfr = 0;
239
240 if (uart_console(uport) || !uart_cts_enabled(uport))
241 return;
242
243 if (!(mctrl & TIOCM_RTS))
244 uart_manual_rfr = UART_MANUAL_RFR_EN | UART_RFR_NOT_READY;
245 writel_relaxed(uart_manual_rfr, uport->membase + SE_UART_MANUAL_RFR);
246 }
247
qcom_geni_serial_get_type(struct uart_port * uport)248 static const char *qcom_geni_serial_get_type(struct uart_port *uport)
249 {
250 return "MSM";
251 }
252
get_port_from_line(int line,bool console)253 static struct qcom_geni_serial_port *get_port_from_line(int line, bool console)
254 {
255 struct qcom_geni_serial_port *port;
256 int nr_ports = console ? GENI_UART_CONS_PORTS : GENI_UART_PORTS;
257
258 if (line < 0 || line >= nr_ports)
259 return ERR_PTR(-ENXIO);
260
261 port = console ? &qcom_geni_console_port : &qcom_geni_uart_ports[line];
262 return port;
263 }
264
qcom_geni_serial_poll_bit(struct uart_port * uport,int offset,int field,bool set)265 static bool qcom_geni_serial_poll_bit(struct uart_port *uport,
266 int offset, int field, bool set)
267 {
268 u32 reg;
269 struct qcom_geni_serial_port *port;
270 unsigned int baud;
271 unsigned int fifo_bits;
272 unsigned long timeout_us = 20000;
273
274 /* Ensure polling is not re-ordered before the prior writes/reads */
275 mb();
276
277 if (uport->private_data) {
278 port = to_dev_port(uport, uport);
279 baud = port->baud;
280 if (!baud)
281 baud = 115200;
282 fifo_bits = port->tx_fifo_depth * port->tx_fifo_width;
283 /*
284 * Total polling iterations based on FIFO worth of bytes to be
285 * sent at current baud. Add a little fluff to the wait.
286 */
287 timeout_us = ((fifo_bits * USEC_PER_SEC) / baud) + 500;
288 }
289
290 /*
291 * Use custom implementation instead of readl_poll_atomic since ktimer
292 * is not ready at the time of early console.
293 */
294 timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10;
295 while (timeout_us) {
296 reg = readl_relaxed(uport->membase + offset);
297 if ((bool)(reg & field) == set)
298 return true;
299 udelay(10);
300 timeout_us -= 10;
301 }
302 return false;
303 }
304
qcom_geni_serial_setup_tx(struct uart_port * uport,u32 xmit_size)305 static void qcom_geni_serial_setup_tx(struct uart_port *uport, u32 xmit_size)
306 {
307 u32 m_cmd;
308
309 writel_relaxed(xmit_size, uport->membase + SE_UART_TX_TRANS_LEN);
310 m_cmd = UART_START_TX << M_OPCODE_SHFT;
311 writel(m_cmd, uport->membase + SE_GENI_M_CMD0);
312 }
313
qcom_geni_serial_poll_tx_done(struct uart_port * uport)314 static void qcom_geni_serial_poll_tx_done(struct uart_port *uport)
315 {
316 int done;
317 u32 irq_clear = M_CMD_DONE_EN;
318
319 done = qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
320 M_CMD_DONE_EN, true);
321 if (!done) {
322 writel_relaxed(M_GENI_CMD_ABORT, uport->membase +
323 SE_GENI_M_CMD_CTRL_REG);
324 irq_clear |= M_CMD_ABORT_EN;
325 qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
326 M_CMD_ABORT_EN, true);
327 }
328 writel_relaxed(irq_clear, uport->membase + SE_GENI_M_IRQ_CLEAR);
329 }
330
qcom_geni_serial_abort_rx(struct uart_port * uport)331 static void qcom_geni_serial_abort_rx(struct uart_port *uport)
332 {
333 u32 irq_clear = S_CMD_DONE_EN | S_CMD_ABORT_EN;
334
335 writel(S_GENI_CMD_ABORT, uport->membase + SE_GENI_S_CMD_CTRL_REG);
336 qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG,
337 S_GENI_CMD_ABORT, false);
338 writel_relaxed(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR);
339 writel_relaxed(FORCE_DEFAULT, uport->membase + GENI_FORCE_DEFAULT_REG);
340 }
341
342 #ifdef CONFIG_CONSOLE_POLL
qcom_geni_serial_get_char(struct uart_port * uport)343 static int qcom_geni_serial_get_char(struct uart_port *uport)
344 {
345 u32 rx_fifo;
346 u32 status;
347
348 status = readl_relaxed(uport->membase + SE_GENI_M_IRQ_STATUS);
349 writel_relaxed(status, uport->membase + SE_GENI_M_IRQ_CLEAR);
350
351 status = readl_relaxed(uport->membase + SE_GENI_S_IRQ_STATUS);
352 writel_relaxed(status, uport->membase + SE_GENI_S_IRQ_CLEAR);
353
354 /*
355 * Ensure the writes to clear interrupts is not re-ordered after
356 * reading the data.
357 */
358 mb();
359
360 status = readl_relaxed(uport->membase + SE_GENI_RX_FIFO_STATUS);
361 if (!(status & RX_FIFO_WC_MSK))
362 return NO_POLL_CHAR;
363
364 rx_fifo = readl(uport->membase + SE_GENI_RX_FIFOn);
365 return rx_fifo & 0xff;
366 }
367
qcom_geni_serial_poll_put_char(struct uart_port * uport,unsigned char c)368 static void qcom_geni_serial_poll_put_char(struct uart_port *uport,
369 unsigned char c)
370 {
371 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
372
373 writel_relaxed(port->tx_wm, uport->membase + SE_GENI_TX_WATERMARK_REG);
374 qcom_geni_serial_setup_tx(uport, 1);
375 WARN_ON(!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
376 M_TX_FIFO_WATERMARK_EN, true));
377 writel_relaxed(c, uport->membase + SE_GENI_TX_FIFOn);
378 writel_relaxed(M_TX_FIFO_WATERMARK_EN, uport->membase +
379 SE_GENI_M_IRQ_CLEAR);
380 qcom_geni_serial_poll_tx_done(uport);
381 }
382 #endif
383
384 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
qcom_geni_serial_wr_char(struct uart_port * uport,int ch)385 static void qcom_geni_serial_wr_char(struct uart_port *uport, int ch)
386 {
387 writel_relaxed(ch, uport->membase + SE_GENI_TX_FIFOn);
388 }
389
390 static void
__qcom_geni_serial_console_write(struct uart_port * uport,const char * s,unsigned int count)391 __qcom_geni_serial_console_write(struct uart_port *uport, const char *s,
392 unsigned int count)
393 {
394 int i;
395 u32 bytes_to_send = count;
396
397 for (i = 0; i < count; i++) {
398 /*
399 * uart_console_write() adds a carriage return for each newline.
400 * Account for additional bytes to be written.
401 */
402 if (s[i] == '\n')
403 bytes_to_send++;
404 }
405
406 writel_relaxed(DEF_TX_WM, uport->membase + SE_GENI_TX_WATERMARK_REG);
407 qcom_geni_serial_setup_tx(uport, bytes_to_send);
408 for (i = 0; i < count; ) {
409 size_t chars_to_write = 0;
410 size_t avail = DEF_FIFO_DEPTH_WORDS - DEF_TX_WM;
411
412 /*
413 * If the WM bit never set, then the Tx state machine is not
414 * in a valid state, so break, cancel/abort any existing
415 * command. Unfortunately the current data being written is
416 * lost.
417 */
418 if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
419 M_TX_FIFO_WATERMARK_EN, true))
420 break;
421 chars_to_write = min_t(size_t, count - i, avail / 2);
422 uart_console_write(uport, s + i, chars_to_write,
423 qcom_geni_serial_wr_char);
424 writel_relaxed(M_TX_FIFO_WATERMARK_EN, uport->membase +
425 SE_GENI_M_IRQ_CLEAR);
426 i += chars_to_write;
427 }
428 qcom_geni_serial_poll_tx_done(uport);
429 }
430
qcom_geni_serial_console_write(struct console * co,const char * s,unsigned int count)431 static void qcom_geni_serial_console_write(struct console *co, const char *s,
432 unsigned int count)
433 {
434 struct uart_port *uport;
435 struct qcom_geni_serial_port *port;
436 bool locked = true;
437 unsigned long flags;
438
439 WARN_ON(co->index < 0 || co->index >= GENI_UART_CONS_PORTS);
440
441 port = get_port_from_line(co->index, true);
442 if (IS_ERR(port))
443 return;
444
445 uport = &port->uport;
446 if (oops_in_progress)
447 locked = spin_trylock_irqsave(&uport->lock, flags);
448 else
449 spin_lock_irqsave(&uport->lock, flags);
450
451 /* Cancel the current write to log the fault */
452 if (!locked) {
453 geni_se_cancel_m_cmd(&port->se);
454 if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
455 M_CMD_CANCEL_EN, true)) {
456 geni_se_abort_m_cmd(&port->se);
457 qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
458 M_CMD_ABORT_EN, true);
459 writel_relaxed(M_CMD_ABORT_EN, uport->membase +
460 SE_GENI_M_IRQ_CLEAR);
461 }
462 writel_relaxed(M_CMD_CANCEL_EN, uport->membase +
463 SE_GENI_M_IRQ_CLEAR);
464 }
465
466 __qcom_geni_serial_console_write(uport, s, count);
467 if (locked)
468 spin_unlock_irqrestore(&uport->lock, flags);
469 }
470
handle_rx_console(struct uart_port * uport,u32 bytes,bool drop)471 static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
472 {
473 u32 i;
474 unsigned char buf[sizeof(u32)];
475 struct tty_port *tport;
476 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
477
478 tport = &uport->state->port;
479 for (i = 0; i < bytes; ) {
480 int c;
481 int chunk = min_t(int, bytes - i, port->rx_bytes_pw);
482
483 ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, buf, 1);
484 i += chunk;
485 if (drop)
486 continue;
487
488 for (c = 0; c < chunk; c++) {
489 int sysrq;
490
491 uport->icount.rx++;
492 if (port->brk && buf[c] == 0) {
493 port->brk = false;
494 if (uart_handle_break(uport))
495 continue;
496 }
497
498 sysrq = uart_handle_sysrq_char(uport, buf[c]);
499 if (!sysrq)
500 tty_insert_flip_char(tport, buf[c], TTY_NORMAL);
501 }
502 }
503 if (!drop)
504 tty_flip_buffer_push(tport);
505 return 0;
506 }
507 #else
handle_rx_console(struct uart_port * uport,u32 bytes,bool drop)508 static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop)
509 {
510 return -EPERM;
511 }
512
513 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
514
handle_rx_uart(struct uart_port * uport,u32 bytes,bool drop)515 static int handle_rx_uart(struct uart_port *uport, u32 bytes, bool drop)
516 {
517 unsigned char *buf;
518 struct tty_port *tport;
519 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
520 u32 num_bytes_pw = port->tx_fifo_width / BITS_PER_BYTE;
521 u32 words = ALIGN(bytes, num_bytes_pw) / num_bytes_pw;
522 int ret;
523
524 tport = &uport->state->port;
525 ioread32_rep(uport->membase + SE_GENI_RX_FIFOn, port->rx_fifo, words);
526 if (drop)
527 return 0;
528
529 buf = (unsigned char *)port->rx_fifo;
530 ret = tty_insert_flip_string(tport, buf, bytes);
531 if (ret != bytes) {
532 dev_err(uport->dev, "%s:Unable to push data ret %d_bytes %d\n",
533 __func__, ret, bytes);
534 WARN_ON_ONCE(1);
535 }
536 uport->icount.rx += ret;
537 tty_flip_buffer_push(tport);
538 return ret;
539 }
540
qcom_geni_serial_start_tx(struct uart_port * uport)541 static void qcom_geni_serial_start_tx(struct uart_port *uport)
542 {
543 u32 irq_en;
544 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
545 u32 status;
546
547 if (port->xfer_mode == GENI_SE_FIFO) {
548 /*
549 * readl ensures reading & writing of IRQ_EN register
550 * is not re-ordered before checking the status of the
551 * Serial Engine.
552 */
553 status = readl(uport->membase + SE_GENI_STATUS);
554 if (status & M_GENI_CMD_ACTIVE)
555 return;
556
557 if (!qcom_geni_serial_tx_empty(uport))
558 return;
559
560 irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN);
561 irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
562
563 writel_relaxed(port->tx_wm, uport->membase +
564 SE_GENI_TX_WATERMARK_REG);
565 writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
566 }
567 }
568
qcom_geni_serial_stop_tx(struct uart_port * uport)569 static void qcom_geni_serial_stop_tx(struct uart_port *uport)
570 {
571 u32 irq_en;
572 u32 status;
573 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
574
575 irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN);
576 irq_en &= ~M_CMD_DONE_EN;
577 if (port->xfer_mode == GENI_SE_FIFO) {
578 irq_en &= ~M_TX_FIFO_WATERMARK_EN;
579 writel_relaxed(0, uport->membase +
580 SE_GENI_TX_WATERMARK_REG);
581 }
582 writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
583 status = readl_relaxed(uport->membase + SE_GENI_STATUS);
584 /* Possible stop tx is called multiple times. */
585 if (!(status & M_GENI_CMD_ACTIVE))
586 return;
587
588 /*
589 * Ensure cancel command write is not re-ordered before checking
590 * the status of the Primary Sequencer.
591 */
592 mb();
593
594 geni_se_cancel_m_cmd(&port->se);
595 if (!qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
596 M_CMD_CANCEL_EN, true)) {
597 geni_se_abort_m_cmd(&port->se);
598 qcom_geni_serial_poll_bit(uport, SE_GENI_M_IRQ_STATUS,
599 M_CMD_ABORT_EN, true);
600 writel_relaxed(M_CMD_ABORT_EN, uport->membase +
601 SE_GENI_M_IRQ_CLEAR);
602 }
603 writel_relaxed(M_CMD_CANCEL_EN, uport->membase + SE_GENI_M_IRQ_CLEAR);
604 }
605
qcom_geni_serial_start_rx(struct uart_port * uport)606 static void qcom_geni_serial_start_rx(struct uart_port *uport)
607 {
608 u32 irq_en;
609 u32 status;
610 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
611
612 status = readl_relaxed(uport->membase + SE_GENI_STATUS);
613 if (status & S_GENI_CMD_ACTIVE)
614 qcom_geni_serial_stop_rx(uport);
615
616 /*
617 * Ensure setup command write is not re-ordered before checking
618 * the status of the Secondary Sequencer.
619 */
620 mb();
621
622 geni_se_setup_s_cmd(&port->se, UART_START_READ, 0);
623
624 if (port->xfer_mode == GENI_SE_FIFO) {
625 irq_en = readl_relaxed(uport->membase + SE_GENI_S_IRQ_EN);
626 irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN;
627 writel_relaxed(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
628
629 irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN);
630 irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
631 writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
632 }
633 }
634
qcom_geni_serial_stop_rx(struct uart_port * uport)635 static void qcom_geni_serial_stop_rx(struct uart_port *uport)
636 {
637 u32 irq_en;
638 u32 status;
639 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
640 u32 irq_clear = S_CMD_DONE_EN;
641
642 if (port->xfer_mode == GENI_SE_FIFO) {
643 irq_en = readl_relaxed(uport->membase + SE_GENI_S_IRQ_EN);
644 irq_en &= ~(S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN);
645 writel_relaxed(irq_en, uport->membase + SE_GENI_S_IRQ_EN);
646
647 irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN);
648 irq_en &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
649 writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
650 }
651
652 status = readl_relaxed(uport->membase + SE_GENI_STATUS);
653 /* Possible stop rx is called multiple times. */
654 if (!(status & S_GENI_CMD_ACTIVE))
655 return;
656
657 /*
658 * Ensure cancel command write is not re-ordered before checking
659 * the status of the Secondary Sequencer.
660 */
661 mb();
662
663 geni_se_cancel_s_cmd(&port->se);
664 qcom_geni_serial_poll_bit(uport, SE_GENI_S_CMD_CTRL_REG,
665 S_GENI_CMD_CANCEL, false);
666 status = readl_relaxed(uport->membase + SE_GENI_STATUS);
667 writel_relaxed(irq_clear, uport->membase + SE_GENI_S_IRQ_CLEAR);
668 if (status & S_GENI_CMD_ACTIVE)
669 qcom_geni_serial_abort_rx(uport);
670 }
671
qcom_geni_serial_handle_rx(struct uart_port * uport,bool drop)672 static void qcom_geni_serial_handle_rx(struct uart_port *uport, bool drop)
673 {
674 u32 status;
675 u32 word_cnt;
676 u32 last_word_byte_cnt;
677 u32 last_word_partial;
678 u32 total_bytes;
679 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
680
681 status = readl_relaxed(uport->membase + SE_GENI_RX_FIFO_STATUS);
682 word_cnt = status & RX_FIFO_WC_MSK;
683 last_word_partial = status & RX_LAST;
684 last_word_byte_cnt = (status & RX_LAST_BYTE_VALID_MSK) >>
685 RX_LAST_BYTE_VALID_SHFT;
686
687 if (!word_cnt)
688 return;
689 total_bytes = port->rx_bytes_pw * (word_cnt - 1);
690 if (last_word_partial && last_word_byte_cnt)
691 total_bytes += last_word_byte_cnt;
692 else
693 total_bytes += port->rx_bytes_pw;
694 port->handle_rx(uport, total_bytes, drop);
695 }
696
qcom_geni_serial_handle_tx(struct uart_port * uport)697 static void qcom_geni_serial_handle_tx(struct uart_port *uport)
698 {
699 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
700 struct circ_buf *xmit = &uport->state->xmit;
701 size_t avail;
702 size_t remaining;
703 int i;
704 u32 status;
705 unsigned int chunk;
706 int tail;
707 u32 irq_en;
708
709 chunk = uart_circ_chars_pending(xmit);
710 status = readl_relaxed(uport->membase + SE_GENI_TX_FIFO_STATUS);
711 /* Both FIFO and framework buffer are drained */
712 if (!chunk && !status) {
713 qcom_geni_serial_stop_tx(uport);
714 goto out_write_wakeup;
715 }
716
717 if (!uart_console(uport)) {
718 irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN);
719 irq_en &= ~(M_TX_FIFO_WATERMARK_EN);
720 writel_relaxed(0, uport->membase + SE_GENI_TX_WATERMARK_REG);
721 writel_relaxed(irq_en, uport->membase + SE_GENI_M_IRQ_EN);
722 }
723
724 avail = (port->tx_fifo_depth - port->tx_wm) * port->tx_bytes_pw;
725 tail = xmit->tail;
726 chunk = min3((size_t)chunk, (size_t)(UART_XMIT_SIZE - tail), avail);
727 if (!chunk)
728 goto out_write_wakeup;
729
730 qcom_geni_serial_setup_tx(uport, chunk);
731
732 remaining = chunk;
733 for (i = 0; i < chunk; ) {
734 unsigned int tx_bytes;
735 u8 buf[sizeof(u32)];
736 int c;
737
738 memset(buf, 0, ARRAY_SIZE(buf));
739 tx_bytes = min_t(size_t, remaining, port->tx_bytes_pw);
740 for (c = 0; c < tx_bytes ; c++)
741 buf[c] = xmit->buf[tail + c];
742
743 iowrite32_rep(uport->membase + SE_GENI_TX_FIFOn, buf, 1);
744
745 i += tx_bytes;
746 tail += tx_bytes;
747 uport->icount.tx += tx_bytes;
748 remaining -= tx_bytes;
749 }
750
751 xmit->tail = tail & (UART_XMIT_SIZE - 1);
752 if (uart_console(uport))
753 qcom_geni_serial_poll_tx_done(uport);
754 out_write_wakeup:
755 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
756 uart_write_wakeup(uport);
757 }
758
qcom_geni_serial_isr(int isr,void * dev)759 static irqreturn_t qcom_geni_serial_isr(int isr, void *dev)
760 {
761 unsigned int m_irq_status;
762 unsigned int s_irq_status;
763 struct uart_port *uport = dev;
764 unsigned long flags;
765 unsigned int m_irq_en;
766 bool drop_rx = false;
767 struct tty_port *tport = &uport->state->port;
768 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
769
770 if (uport->suspended)
771 return IRQ_NONE;
772
773 spin_lock_irqsave(&uport->lock, flags);
774 m_irq_status = readl_relaxed(uport->membase + SE_GENI_M_IRQ_STATUS);
775 s_irq_status = readl_relaxed(uport->membase + SE_GENI_S_IRQ_STATUS);
776 m_irq_en = readl_relaxed(uport->membase + SE_GENI_M_IRQ_EN);
777 writel_relaxed(m_irq_status, uport->membase + SE_GENI_M_IRQ_CLEAR);
778 writel_relaxed(s_irq_status, uport->membase + SE_GENI_S_IRQ_CLEAR);
779
780 if (WARN_ON(m_irq_status & M_ILLEGAL_CMD_EN))
781 goto out_unlock;
782
783 if (s_irq_status & S_RX_FIFO_WR_ERR_EN) {
784 uport->icount.overrun++;
785 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
786 }
787
788 if (m_irq_status & (M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN) &&
789 m_irq_en & (M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN))
790 qcom_geni_serial_handle_tx(uport);
791
792 if (s_irq_status & S_GP_IRQ_0_EN || s_irq_status & S_GP_IRQ_1_EN) {
793 if (s_irq_status & S_GP_IRQ_0_EN)
794 uport->icount.parity++;
795 drop_rx = true;
796 } else if (s_irq_status & S_GP_IRQ_2_EN ||
797 s_irq_status & S_GP_IRQ_3_EN) {
798 uport->icount.brk++;
799 port->brk = true;
800 }
801
802 if (s_irq_status & S_RX_FIFO_WATERMARK_EN ||
803 s_irq_status & S_RX_FIFO_LAST_EN)
804 qcom_geni_serial_handle_rx(uport, drop_rx);
805
806 out_unlock:
807 spin_unlock_irqrestore(&uport->lock, flags);
808 return IRQ_HANDLED;
809 }
810
get_tx_fifo_size(struct qcom_geni_serial_port * port)811 static void get_tx_fifo_size(struct qcom_geni_serial_port *port)
812 {
813 struct uart_port *uport;
814
815 uport = &port->uport;
816 port->tx_fifo_depth = geni_se_get_tx_fifo_depth(&port->se);
817 port->tx_fifo_width = geni_se_get_tx_fifo_width(&port->se);
818 port->rx_fifo_depth = geni_se_get_rx_fifo_depth(&port->se);
819 uport->fifosize =
820 (port->tx_fifo_depth * port->tx_fifo_width) / BITS_PER_BYTE;
821 }
822
set_rfr_wm(struct qcom_geni_serial_port * port)823 static void set_rfr_wm(struct qcom_geni_serial_port *port)
824 {
825 /*
826 * Set RFR (Flow off) to FIFO_DEPTH - 2.
827 * RX WM level at 10% RX_FIFO_DEPTH.
828 * TX WM level at 10% TX_FIFO_DEPTH.
829 */
830 port->rx_rfr = port->rx_fifo_depth - 2;
831 port->rx_wm = UART_CONSOLE_RX_WM;
832 port->tx_wm = DEF_TX_WM;
833 }
834
qcom_geni_serial_shutdown(struct uart_port * uport)835 static void qcom_geni_serial_shutdown(struct uart_port *uport)
836 {
837 unsigned long flags;
838
839 /* Stop the console before stopping the current tx */
840 if (uart_console(uport))
841 console_stop(uport->cons);
842
843 free_irq(uport->irq, uport);
844 spin_lock_irqsave(&uport->lock, flags);
845 qcom_geni_serial_stop_tx(uport);
846 qcom_geni_serial_stop_rx(uport);
847 spin_unlock_irqrestore(&uport->lock, flags);
848 }
849
qcom_geni_serial_port_setup(struct uart_port * uport)850 static int qcom_geni_serial_port_setup(struct uart_port *uport)
851 {
852 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
853 unsigned int rxstale = DEFAULT_BITS_PER_CHAR * STALE_TIMEOUT;
854
855 set_rfr_wm(port);
856 writel_relaxed(rxstale, uport->membase + SE_UART_RX_STALE_CNT);
857 /*
858 * Make an unconditional cancel on the main sequencer to reset
859 * it else we could end up in data loss scenarios.
860 */
861 port->xfer_mode = GENI_SE_FIFO;
862 if (uart_console(uport))
863 qcom_geni_serial_poll_tx_done(uport);
864 geni_se_config_packing(&port->se, BITS_PER_BYTE, port->tx_bytes_pw,
865 false, true, false);
866 geni_se_config_packing(&port->se, BITS_PER_BYTE, port->rx_bytes_pw,
867 false, false, true);
868 geni_se_init(&port->se, port->rx_wm, port->rx_rfr);
869 geni_se_select_mode(&port->se, port->xfer_mode);
870 if (!uart_console(uport)) {
871 port->rx_fifo = devm_kcalloc(uport->dev,
872 port->rx_fifo_depth, sizeof(u32), GFP_KERNEL);
873 if (!port->rx_fifo)
874 return -ENOMEM;
875 }
876 port->setup = true;
877 return 0;
878 }
879
qcom_geni_serial_startup(struct uart_port * uport)880 static int qcom_geni_serial_startup(struct uart_port *uport)
881 {
882 int ret;
883 u32 proto;
884 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
885
886 scnprintf(port->name, sizeof(port->name),
887 "qcom_serial_%s%d",
888 (uart_console(uport) ? "console" : "uart"), uport->line);
889
890 if (!uart_console(uport)) {
891 port->tx_bytes_pw = 4;
892 port->rx_bytes_pw = RX_BYTES_PW;
893 }
894 proto = geni_se_read_proto(&port->se);
895 if (proto != GENI_SE_UART) {
896 dev_err(uport->dev, "Invalid FW loaded, proto: %d\n", proto);
897 return -ENXIO;
898 }
899
900 get_tx_fifo_size(port);
901 if (!port->setup) {
902 ret = qcom_geni_serial_port_setup(uport);
903 if (ret)
904 return ret;
905 }
906
907 ret = request_irq(uport->irq, qcom_geni_serial_isr, IRQF_TRIGGER_HIGH,
908 port->name, uport);
909 if (ret)
910 dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret);
911 return ret;
912 }
913
get_clk_cfg(unsigned long clk_freq)914 static unsigned long get_clk_cfg(unsigned long clk_freq)
915 {
916 int i;
917
918 for (i = 0; i < ARRAY_SIZE(root_freq); i++) {
919 if (!(root_freq[i] % clk_freq))
920 return root_freq[i];
921 }
922 return 0;
923 }
924
get_clk_div_rate(unsigned int baud,unsigned int * clk_div)925 static unsigned long get_clk_div_rate(unsigned int baud, unsigned int *clk_div)
926 {
927 unsigned long ser_clk;
928 unsigned long desired_clk;
929
930 desired_clk = baud * UART_OVERSAMPLING;
931 ser_clk = get_clk_cfg(desired_clk);
932 if (!ser_clk) {
933 pr_err("%s: Can't find matching DFS entry for baud %d\n",
934 __func__, baud);
935 return ser_clk;
936 }
937
938 *clk_div = ser_clk / desired_clk;
939 return ser_clk;
940 }
941
qcom_geni_serial_set_termios(struct uart_port * uport,struct ktermios * termios,struct ktermios * old)942 static void qcom_geni_serial_set_termios(struct uart_port *uport,
943 struct ktermios *termios, struct ktermios *old)
944 {
945 unsigned int baud;
946 unsigned int bits_per_char;
947 unsigned int tx_trans_cfg;
948 unsigned int tx_parity_cfg;
949 unsigned int rx_trans_cfg;
950 unsigned int rx_parity_cfg;
951 unsigned int stop_bit_len;
952 unsigned int clk_div;
953 unsigned long ser_clk_cfg;
954 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
955 unsigned long clk_rate;
956
957 qcom_geni_serial_stop_rx(uport);
958 /* baud rate */
959 baud = uart_get_baud_rate(uport, termios, old, 300, 4000000);
960 port->baud = baud;
961 clk_rate = get_clk_div_rate(baud, &clk_div);
962 if (!clk_rate)
963 goto out_restart_rx;
964
965 uport->uartclk = clk_rate;
966 clk_set_rate(port->se.clk, clk_rate);
967 ser_clk_cfg = SER_CLK_EN;
968 ser_clk_cfg |= clk_div << CLK_DIV_SHFT;
969
970 /* parity */
971 tx_trans_cfg = readl_relaxed(uport->membase + SE_UART_TX_TRANS_CFG);
972 tx_parity_cfg = readl_relaxed(uport->membase + SE_UART_TX_PARITY_CFG);
973 rx_trans_cfg = readl_relaxed(uport->membase + SE_UART_RX_TRANS_CFG);
974 rx_parity_cfg = readl_relaxed(uport->membase + SE_UART_RX_PARITY_CFG);
975 if (termios->c_cflag & PARENB) {
976 tx_trans_cfg |= UART_TX_PAR_EN;
977 rx_trans_cfg |= UART_RX_PAR_EN;
978 tx_parity_cfg |= PAR_CALC_EN;
979 rx_parity_cfg |= PAR_CALC_EN;
980 if (termios->c_cflag & PARODD) {
981 tx_parity_cfg |= PAR_ODD;
982 rx_parity_cfg |= PAR_ODD;
983 } else if (termios->c_cflag & CMSPAR) {
984 tx_parity_cfg |= PAR_SPACE;
985 rx_parity_cfg |= PAR_SPACE;
986 } else {
987 tx_parity_cfg |= PAR_EVEN;
988 rx_parity_cfg |= PAR_EVEN;
989 }
990 } else {
991 tx_trans_cfg &= ~UART_TX_PAR_EN;
992 rx_trans_cfg &= ~UART_RX_PAR_EN;
993 tx_parity_cfg &= ~PAR_CALC_EN;
994 rx_parity_cfg &= ~PAR_CALC_EN;
995 }
996
997 /* bits per char */
998 switch (termios->c_cflag & CSIZE) {
999 case CS5:
1000 bits_per_char = 5;
1001 break;
1002 case CS6:
1003 bits_per_char = 6;
1004 break;
1005 case CS7:
1006 bits_per_char = 7;
1007 break;
1008 case CS8:
1009 default:
1010 bits_per_char = 8;
1011 break;
1012 }
1013
1014 /* stop bits */
1015 if (termios->c_cflag & CSTOPB)
1016 stop_bit_len = TX_STOP_BIT_LEN_2;
1017 else
1018 stop_bit_len = TX_STOP_BIT_LEN_1;
1019
1020 /* flow control, clear the CTS_MASK bit if using flow control. */
1021 if (termios->c_cflag & CRTSCTS)
1022 tx_trans_cfg &= ~UART_CTS_MASK;
1023 else
1024 tx_trans_cfg |= UART_CTS_MASK;
1025
1026 if (baud)
1027 uart_update_timeout(uport, termios->c_cflag, baud);
1028
1029 if (!uart_console(uport))
1030 writel_relaxed(port->loopback,
1031 uport->membase + SE_UART_LOOPBACK_CFG);
1032 writel_relaxed(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1033 writel_relaxed(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1034 writel_relaxed(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1035 writel_relaxed(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1036 writel_relaxed(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1037 writel_relaxed(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1038 writel_relaxed(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1039 writel_relaxed(ser_clk_cfg, uport->membase + GENI_SER_M_CLK_CFG);
1040 writel_relaxed(ser_clk_cfg, uport->membase + GENI_SER_S_CLK_CFG);
1041 out_restart_rx:
1042 qcom_geni_serial_start_rx(uport);
1043 }
1044
qcom_geni_serial_tx_empty(struct uart_port * uport)1045 static unsigned int qcom_geni_serial_tx_empty(struct uart_port *uport)
1046 {
1047 return !readl(uport->membase + SE_GENI_TX_FIFO_STATUS);
1048 }
1049
1050 #ifdef CONFIG_SERIAL_QCOM_GENI_CONSOLE
qcom_geni_console_setup(struct console * co,char * options)1051 static int __init qcom_geni_console_setup(struct console *co, char *options)
1052 {
1053 struct uart_port *uport;
1054 struct qcom_geni_serial_port *port;
1055 int baud;
1056 int bits = 8;
1057 int parity = 'n';
1058 int flow = 'n';
1059
1060 if (co->index >= GENI_UART_CONS_PORTS || co->index < 0)
1061 return -ENXIO;
1062
1063 port = get_port_from_line(co->index, true);
1064 if (IS_ERR(port)) {
1065 pr_err("Invalid line %d\n", co->index);
1066 return PTR_ERR(port);
1067 }
1068
1069 uport = &port->uport;
1070
1071 if (unlikely(!uport->membase))
1072 return -ENXIO;
1073
1074 if (geni_se_resources_on(&port->se)) {
1075 dev_err(port->se.dev, "Error turning on resources\n");
1076 return -ENXIO;
1077 }
1078
1079 if (unlikely(geni_se_read_proto(&port->se) != GENI_SE_UART)) {
1080 geni_se_resources_off(&port->se);
1081 return -ENXIO;
1082 }
1083
1084 if (!port->setup) {
1085 port->tx_bytes_pw = 1;
1086 port->rx_bytes_pw = RX_BYTES_PW;
1087 qcom_geni_serial_stop_rx(uport);
1088 qcom_geni_serial_port_setup(uport);
1089 }
1090
1091 if (options)
1092 uart_parse_options(options, &baud, &parity, &bits, &flow);
1093
1094 return uart_set_options(uport, co, baud, parity, bits, flow);
1095 }
1096
qcom_geni_serial_earlycon_write(struct console * con,const char * s,unsigned int n)1097 static void qcom_geni_serial_earlycon_write(struct console *con,
1098 const char *s, unsigned int n)
1099 {
1100 struct earlycon_device *dev = con->data;
1101
1102 __qcom_geni_serial_console_write(&dev->port, s, n);
1103 }
1104
qcom_geni_serial_earlycon_setup(struct earlycon_device * dev,const char * opt)1105 static int __init qcom_geni_serial_earlycon_setup(struct earlycon_device *dev,
1106 const char *opt)
1107 {
1108 struct uart_port *uport = &dev->port;
1109 u32 tx_trans_cfg;
1110 u32 tx_parity_cfg = 0; /* Disable Tx Parity */
1111 u32 rx_trans_cfg = 0;
1112 u32 rx_parity_cfg = 0; /* Disable Rx Parity */
1113 u32 stop_bit_len = 0; /* Default stop bit length - 1 bit */
1114 u32 bits_per_char;
1115 struct geni_se se;
1116
1117 if (!uport->membase)
1118 return -EINVAL;
1119
1120 memset(&se, 0, sizeof(se));
1121 se.base = uport->membase;
1122 if (geni_se_read_proto(&se) != GENI_SE_UART)
1123 return -ENXIO;
1124 /*
1125 * Ignore Flow control.
1126 * n = 8.
1127 */
1128 tx_trans_cfg = UART_CTS_MASK;
1129 bits_per_char = BITS_PER_BYTE;
1130
1131 /*
1132 * Make an unconditional cancel on the main sequencer to reset
1133 * it else we could end up in data loss scenarios.
1134 */
1135 qcom_geni_serial_poll_tx_done(uport);
1136 qcom_geni_serial_abort_rx(uport);
1137 geni_se_config_packing(&se, BITS_PER_BYTE, 1, false, true, false);
1138 geni_se_init(&se, DEF_FIFO_DEPTH_WORDS / 2, DEF_FIFO_DEPTH_WORDS - 2);
1139 geni_se_select_mode(&se, GENI_SE_FIFO);
1140
1141 writel_relaxed(tx_trans_cfg, uport->membase + SE_UART_TX_TRANS_CFG);
1142 writel_relaxed(tx_parity_cfg, uport->membase + SE_UART_TX_PARITY_CFG);
1143 writel_relaxed(rx_trans_cfg, uport->membase + SE_UART_RX_TRANS_CFG);
1144 writel_relaxed(rx_parity_cfg, uport->membase + SE_UART_RX_PARITY_CFG);
1145 writel_relaxed(bits_per_char, uport->membase + SE_UART_TX_WORD_LEN);
1146 writel_relaxed(bits_per_char, uport->membase + SE_UART_RX_WORD_LEN);
1147 writel_relaxed(stop_bit_len, uport->membase + SE_UART_TX_STOP_BIT_LEN);
1148
1149 dev->con->write = qcom_geni_serial_earlycon_write;
1150 dev->con->setup = NULL;
1151 return 0;
1152 }
1153 OF_EARLYCON_DECLARE(qcom_geni, "qcom,geni-debug-uart",
1154 qcom_geni_serial_earlycon_setup);
1155
console_register(struct uart_driver * drv)1156 static int __init console_register(struct uart_driver *drv)
1157 {
1158 return uart_register_driver(drv);
1159 }
1160
console_unregister(struct uart_driver * drv)1161 static void console_unregister(struct uart_driver *drv)
1162 {
1163 uart_unregister_driver(drv);
1164 }
1165
1166 static struct console cons_ops = {
1167 .name = "ttyMSM",
1168 .write = qcom_geni_serial_console_write,
1169 .device = uart_console_device,
1170 .setup = qcom_geni_console_setup,
1171 .flags = CON_PRINTBUFFER,
1172 .index = -1,
1173 .data = &qcom_geni_console_driver,
1174 };
1175
1176 static struct uart_driver qcom_geni_console_driver = {
1177 .owner = THIS_MODULE,
1178 .driver_name = "qcom_geni_console",
1179 .dev_name = "ttyMSM",
1180 .nr = GENI_UART_CONS_PORTS,
1181 .cons = &cons_ops,
1182 };
1183 #else
console_register(struct uart_driver * drv)1184 static int console_register(struct uart_driver *drv)
1185 {
1186 return 0;
1187 }
1188
console_unregister(struct uart_driver * drv)1189 static void console_unregister(struct uart_driver *drv)
1190 {
1191 }
1192 #endif /* CONFIG_SERIAL_QCOM_GENI_CONSOLE */
1193
1194 static struct uart_driver qcom_geni_uart_driver = {
1195 .owner = THIS_MODULE,
1196 .driver_name = "qcom_geni_uart",
1197 .dev_name = "ttyHS",
1198 .nr = GENI_UART_PORTS,
1199 };
1200
qcom_geni_serial_pm(struct uart_port * uport,unsigned int new_state,unsigned int old_state)1201 static void qcom_geni_serial_pm(struct uart_port *uport,
1202 unsigned int new_state, unsigned int old_state)
1203 {
1204 struct qcom_geni_serial_port *port = to_dev_port(uport, uport);
1205
1206 if (new_state == UART_PM_STATE_ON && old_state == UART_PM_STATE_OFF)
1207 geni_se_resources_on(&port->se);
1208 else if (!uart_console(uport) && (new_state == UART_PM_STATE_ON &&
1209 old_state == UART_PM_STATE_UNDEFINED))
1210 geni_se_resources_on(&port->se);
1211 else if (new_state == UART_PM_STATE_OFF &&
1212 old_state == UART_PM_STATE_ON)
1213 geni_se_resources_off(&port->se);
1214 }
1215
1216 static const struct uart_ops qcom_geni_console_pops = {
1217 .tx_empty = qcom_geni_serial_tx_empty,
1218 .stop_tx = qcom_geni_serial_stop_tx,
1219 .start_tx = qcom_geni_serial_start_tx,
1220 .stop_rx = qcom_geni_serial_stop_rx,
1221 .set_termios = qcom_geni_serial_set_termios,
1222 .startup = qcom_geni_serial_startup,
1223 .request_port = qcom_geni_serial_request_port,
1224 .config_port = qcom_geni_serial_config_port,
1225 .shutdown = qcom_geni_serial_shutdown,
1226 .type = qcom_geni_serial_get_type,
1227 .set_mctrl = qcom_geni_serial_set_mctrl,
1228 .get_mctrl = qcom_geni_serial_get_mctrl,
1229 #ifdef CONFIG_CONSOLE_POLL
1230 .poll_get_char = qcom_geni_serial_get_char,
1231 .poll_put_char = qcom_geni_serial_poll_put_char,
1232 #endif
1233 .pm = qcom_geni_serial_pm,
1234 };
1235
1236 static const struct uart_ops qcom_geni_uart_pops = {
1237 .tx_empty = qcom_geni_serial_tx_empty,
1238 .stop_tx = qcom_geni_serial_stop_tx,
1239 .start_tx = qcom_geni_serial_start_tx,
1240 .stop_rx = qcom_geni_serial_stop_rx,
1241 .set_termios = qcom_geni_serial_set_termios,
1242 .startup = qcom_geni_serial_startup,
1243 .request_port = qcom_geni_serial_request_port,
1244 .config_port = qcom_geni_serial_config_port,
1245 .shutdown = qcom_geni_serial_shutdown,
1246 .type = qcom_geni_serial_get_type,
1247 .set_mctrl = qcom_geni_serial_set_mctrl,
1248 .get_mctrl = qcom_geni_serial_get_mctrl,
1249 .pm = qcom_geni_serial_pm,
1250 };
1251
qcom_geni_serial_probe(struct platform_device * pdev)1252 static int qcom_geni_serial_probe(struct platform_device *pdev)
1253 {
1254 int ret = 0;
1255 int line = -1;
1256 struct qcom_geni_serial_port *port;
1257 struct uart_port *uport;
1258 struct resource *res;
1259 int irq;
1260 bool console = false;
1261 struct uart_driver *drv;
1262
1263 if (of_device_is_compatible(pdev->dev.of_node, "qcom,geni-debug-uart"))
1264 console = true;
1265
1266 if (pdev->dev.of_node) {
1267 if (console) {
1268 drv = &qcom_geni_console_driver;
1269 line = of_alias_get_id(pdev->dev.of_node, "serial");
1270 } else {
1271 drv = &qcom_geni_uart_driver;
1272 line = of_alias_get_id(pdev->dev.of_node, "hsuart");
1273 }
1274 }
1275
1276 port = get_port_from_line(line, console);
1277 if (IS_ERR(port)) {
1278 dev_err(&pdev->dev, "Invalid line %d\n", line);
1279 return PTR_ERR(port);
1280 }
1281
1282 uport = &port->uport;
1283 /* Don't allow 2 drivers to access the same port */
1284 if (uport->private_data)
1285 return -ENODEV;
1286
1287 uport->dev = &pdev->dev;
1288 port->se.dev = &pdev->dev;
1289 port->se.wrapper = dev_get_drvdata(pdev->dev.parent);
1290 port->se.clk = devm_clk_get(&pdev->dev, "se");
1291 if (IS_ERR(port->se.clk)) {
1292 ret = PTR_ERR(port->se.clk);
1293 dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret);
1294 return ret;
1295 }
1296
1297 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1298 if (!res)
1299 return -EINVAL;
1300 uport->mapbase = res->start;
1301
1302 port->tx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1303 port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
1304 port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;
1305
1306 irq = platform_get_irq(pdev, 0);
1307 if (irq < 0) {
1308 dev_err(&pdev->dev, "Failed to get IRQ %d\n", irq);
1309 return irq;
1310 }
1311 uport->irq = irq;
1312
1313 uport->private_data = drv;
1314 platform_set_drvdata(pdev, port);
1315 port->handle_rx = console ? handle_rx_console : handle_rx_uart;
1316 if (!console)
1317 device_create_file(uport->dev, &dev_attr_loopback);
1318 return uart_add_one_port(drv, uport);
1319 }
1320
qcom_geni_serial_remove(struct platform_device * pdev)1321 static int qcom_geni_serial_remove(struct platform_device *pdev)
1322 {
1323 struct qcom_geni_serial_port *port = platform_get_drvdata(pdev);
1324 struct uart_driver *drv = port->uport.private_data;
1325
1326 uart_remove_one_port(drv, &port->uport);
1327 return 0;
1328 }
1329
qcom_geni_serial_sys_suspend_noirq(struct device * dev)1330 static int __maybe_unused qcom_geni_serial_sys_suspend_noirq(struct device *dev)
1331 {
1332 struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1333 struct uart_port *uport = &port->uport;
1334
1335 if (uart_console(uport)) {
1336 uart_suspend_port(uport->private_data, uport);
1337 } else {
1338 struct uart_state *state = uport->state;
1339 /*
1340 * If the port is open, deny system suspend.
1341 */
1342 if (state->pm_state == UART_PM_STATE_ON)
1343 return -EBUSY;
1344 }
1345
1346 return 0;
1347 }
1348
qcom_geni_serial_sys_resume_noirq(struct device * dev)1349 static int __maybe_unused qcom_geni_serial_sys_resume_noirq(struct device *dev)
1350 {
1351 struct qcom_geni_serial_port *port = dev_get_drvdata(dev);
1352 struct uart_port *uport = &port->uport;
1353
1354 if (uart_console(uport) &&
1355 console_suspend_enabled && uport->suspended) {
1356 uart_resume_port(uport->private_data, uport);
1357 /*
1358 * uart_suspend_port() invokes port shutdown which in turn
1359 * frees the irq. uart_resume_port invokes port startup which
1360 * performs request_irq. The request_irq auto-enables the IRQ.
1361 * In addition, resume_noirq implicitly enables the IRQ and
1362 * leads to an unbalanced IRQ enable warning. Disable the IRQ
1363 * before returning so that the warning is suppressed.
1364 */
1365 disable_irq(uport->irq);
1366 }
1367 return 0;
1368 }
1369
1370 static const struct dev_pm_ops qcom_geni_serial_pm_ops = {
1371 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(qcom_geni_serial_sys_suspend_noirq,
1372 qcom_geni_serial_sys_resume_noirq)
1373 };
1374
1375 static const struct of_device_id qcom_geni_serial_match_table[] = {
1376 { .compatible = "qcom,geni-debug-uart", },
1377 { .compatible = "qcom,geni-uart", },
1378 {}
1379 };
1380 MODULE_DEVICE_TABLE(of, qcom_geni_serial_match_table);
1381
1382 static struct platform_driver qcom_geni_serial_platform_driver = {
1383 .remove = qcom_geni_serial_remove,
1384 .probe = qcom_geni_serial_probe,
1385 .driver = {
1386 .name = "qcom_geni_serial",
1387 .of_match_table = qcom_geni_serial_match_table,
1388 .pm = &qcom_geni_serial_pm_ops,
1389 },
1390 };
1391
qcom_geni_serial_init(void)1392 static int __init qcom_geni_serial_init(void)
1393 {
1394 int ret;
1395
1396 ret = console_register(&qcom_geni_console_driver);
1397 if (ret)
1398 return ret;
1399
1400 ret = uart_register_driver(&qcom_geni_uart_driver);
1401 if (ret) {
1402 console_unregister(&qcom_geni_console_driver);
1403 return ret;
1404 }
1405
1406 ret = platform_driver_register(&qcom_geni_serial_platform_driver);
1407 if (ret) {
1408 console_unregister(&qcom_geni_console_driver);
1409 uart_unregister_driver(&qcom_geni_uart_driver);
1410 }
1411 return ret;
1412 }
1413 module_init(qcom_geni_serial_init);
1414
qcom_geni_serial_exit(void)1415 static void __exit qcom_geni_serial_exit(void)
1416 {
1417 platform_driver_unregister(&qcom_geni_serial_platform_driver);
1418 console_unregister(&qcom_geni_console_driver);
1419 uart_unregister_driver(&qcom_geni_uart_driver);
1420 }
1421 module_exit(qcom_geni_serial_exit);
1422
1423 MODULE_DESCRIPTION("Serial driver for GENI based QUP cores");
1424 MODULE_LICENSE("GPL v2");
1425