1 /*
2  * Driver for CSR SiRFprimaII onboard UARTs.
3  *
4  * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
5  *
6  * Licensed under GPLv2 or later.
7  */
8 
9 #include <linux/module.h>
10 #include <linux/ioport.h>
11 #include <linux/platform_device.h>
12 #include <linux/init.h>
13 #include <linux/sysrq.h>
14 #include <linux/console.h>
15 #include <linux/tty.h>
16 #include <linux/tty_flip.h>
17 #include <linux/serial_core.h>
18 #include <linux/serial.h>
19 #include <linux/clk.h>
20 #include <linux/of.h>
21 #include <linux/slab.h>
22 #include <linux/io.h>
23 #include <linux/of_gpio.h>
24 #include <linux/dmaengine.h>
25 #include <linux/dma-direction.h>
26 #include <linux/dma-mapping.h>
27 #include <asm/irq.h>
28 #include <asm/mach/irq.h>
29 
30 #include "sirfsoc_uart.h"
31 
32 static unsigned int
33 sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port *sirfport, int count);
34 static unsigned int
35 sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count);
36 static struct uart_driver sirfsoc_uart_drv;
37 
38 static void sirfsoc_uart_tx_dma_complete_callback(void *param);
39 static const struct sirfsoc_baudrate_to_regv baudrate_to_regv[] = {
40 	{4000000, 2359296},
41 	{3500000, 1310721},
42 	{3000000, 1572865},
43 	{2500000, 1245186},
44 	{2000000, 1572866},
45 	{1500000, 1245188},
46 	{1152000, 1638404},
47 	{1000000, 1572869},
48 	{921600, 1114120},
49 	{576000, 1245196},
50 	{500000, 1245198},
51 	{460800, 1572876},
52 	{230400, 1310750},
53 	{115200, 1310781},
54 	{57600, 1310843},
55 	{38400, 1114328},
56 	{19200, 1114545},
57 	{9600, 1114979},
58 };
59 
60 static struct sirfsoc_uart_port *sirf_ports[SIRFSOC_UART_NR];
61 
to_sirfport(struct uart_port * port)62 static inline struct sirfsoc_uart_port *to_sirfport(struct uart_port *port)
63 {
64 	return container_of(port, struct sirfsoc_uart_port, port);
65 }
66 
sirfsoc_uart_tx_empty(struct uart_port * port)67 static inline unsigned int sirfsoc_uart_tx_empty(struct uart_port *port)
68 {
69 	unsigned long reg;
70 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
71 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
72 	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
73 	reg = rd_regl(port, ureg->sirfsoc_tx_fifo_status);
74 	return (reg & ufifo_st->ff_empty(port)) ? TIOCSER_TEMT : 0;
75 }
76 
sirfsoc_uart_get_mctrl(struct uart_port * port)77 static unsigned int sirfsoc_uart_get_mctrl(struct uart_port *port)
78 {
79 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
80 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
81 	if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
82 		goto cts_asserted;
83 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
84 		if (!(rd_regl(port, ureg->sirfsoc_afc_ctrl) &
85 						SIRFUART_AFC_CTS_STATUS))
86 			goto cts_asserted;
87 		else
88 			goto cts_deasserted;
89 	} else {
90 		if (!gpio_get_value(sirfport->cts_gpio))
91 			goto cts_asserted;
92 		else
93 			goto cts_deasserted;
94 	}
95 cts_deasserted:
96 	return TIOCM_CAR | TIOCM_DSR;
97 cts_asserted:
98 	return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
99 }
100 
sirfsoc_uart_set_mctrl(struct uart_port * port,unsigned int mctrl)101 static void sirfsoc_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
102 {
103 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
104 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
105 	unsigned int assert = mctrl & TIOCM_RTS;
106 	unsigned int val = assert ? SIRFUART_AFC_CTRL_RX_THD : 0x0;
107 	unsigned int current_val;
108 
109 	if (mctrl & TIOCM_LOOP) {
110 		if (sirfport->uart_reg->uart_type == SIRF_REAL_UART)
111 			wr_regl(port, ureg->sirfsoc_line_ctrl,
112 				rd_regl(port, ureg->sirfsoc_line_ctrl) |
113 				SIRFUART_LOOP_BACK);
114 		else
115 			wr_regl(port, ureg->sirfsoc_mode1,
116 				rd_regl(port, ureg->sirfsoc_mode1) |
117 				SIRFSOC_USP_LOOP_BACK_CTRL);
118 	} else {
119 		if (sirfport->uart_reg->uart_type == SIRF_REAL_UART)
120 			wr_regl(port, ureg->sirfsoc_line_ctrl,
121 				rd_regl(port, ureg->sirfsoc_line_ctrl) &
122 				~SIRFUART_LOOP_BACK);
123 		else
124 			wr_regl(port, ureg->sirfsoc_mode1,
125 				rd_regl(port, ureg->sirfsoc_mode1) &
126 				~SIRFSOC_USP_LOOP_BACK_CTRL);
127 	}
128 
129 	if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
130 		return;
131 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
132 		current_val = rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0xFF;
133 		val |= current_val;
134 		wr_regl(port, ureg->sirfsoc_afc_ctrl, val);
135 	} else {
136 		if (!val)
137 			gpio_set_value(sirfport->rts_gpio, 1);
138 		else
139 			gpio_set_value(sirfport->rts_gpio, 0);
140 	}
141 }
142 
sirfsoc_uart_stop_tx(struct uart_port * port)143 static void sirfsoc_uart_stop_tx(struct uart_port *port)
144 {
145 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
146 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
147 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
148 
149 	if (sirfport->tx_dma_chan) {
150 		if (sirfport->tx_dma_state == TX_DMA_RUNNING) {
151 			dmaengine_pause(sirfport->tx_dma_chan);
152 			sirfport->tx_dma_state = TX_DMA_PAUSE;
153 		} else {
154 			if (!sirfport->is_atlas7)
155 				wr_regl(port, ureg->sirfsoc_int_en_reg,
156 				rd_regl(port, ureg->sirfsoc_int_en_reg) &
157 				~uint_en->sirfsoc_txfifo_empty_en);
158 			else
159 				wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
160 				uint_en->sirfsoc_txfifo_empty_en);
161 		}
162 	} else {
163 		if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
164 			wr_regl(port, ureg->sirfsoc_tx_rx_en, rd_regl(port,
165 				ureg->sirfsoc_tx_rx_en) & ~SIRFUART_TX_EN);
166 		if (!sirfport->is_atlas7)
167 			wr_regl(port, ureg->sirfsoc_int_en_reg,
168 				rd_regl(port, ureg->sirfsoc_int_en_reg) &
169 				~uint_en->sirfsoc_txfifo_empty_en);
170 		else
171 			wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
172 				uint_en->sirfsoc_txfifo_empty_en);
173 	}
174 }
175 
sirfsoc_uart_tx_with_dma(struct sirfsoc_uart_port * sirfport)176 static void sirfsoc_uart_tx_with_dma(struct sirfsoc_uart_port *sirfport)
177 {
178 	struct uart_port *port = &sirfport->port;
179 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
180 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
181 	struct circ_buf *xmit = &port->state->xmit;
182 	unsigned long tran_size;
183 	unsigned long tran_start;
184 	unsigned long pio_tx_size;
185 
186 	tran_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
187 	tran_start = (unsigned long)(xmit->buf + xmit->tail);
188 	if (uart_circ_empty(xmit) || uart_tx_stopped(port) ||
189 			!tran_size)
190 		return;
191 	if (sirfport->tx_dma_state == TX_DMA_PAUSE) {
192 		dmaengine_resume(sirfport->tx_dma_chan);
193 		return;
194 	}
195 	if (sirfport->tx_dma_state == TX_DMA_RUNNING)
196 		return;
197 	if (!sirfport->is_atlas7)
198 		wr_regl(port, ureg->sirfsoc_int_en_reg,
199 				rd_regl(port, ureg->sirfsoc_int_en_reg)&
200 				~(uint_en->sirfsoc_txfifo_empty_en));
201 	else
202 		wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
203 				uint_en->sirfsoc_txfifo_empty_en);
204 	/*
205 	 * DMA requires buffer address and buffer length are both aligned with
206 	 * 4 bytes, so we use PIO for
207 	 * 1. if address is not aligned with 4bytes, use PIO for the first 1~3
208 	 * bytes, and move to DMA for the left part aligned with 4bytes
209 	 * 2. if buffer length is not aligned with 4bytes, use DMA for aligned
210 	 * part first, move to PIO for the left 1~3 bytes
211 	 */
212 	if (tran_size < 4 || BYTES_TO_ALIGN(tran_start)) {
213 		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
214 		wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
215 			rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl)|
216 			SIRFUART_IO_MODE);
217 		if (BYTES_TO_ALIGN(tran_start)) {
218 			pio_tx_size = sirfsoc_uart_pio_tx_chars(sirfport,
219 				BYTES_TO_ALIGN(tran_start));
220 			tran_size -= pio_tx_size;
221 		}
222 		if (tran_size < 4)
223 			sirfsoc_uart_pio_tx_chars(sirfport, tran_size);
224 		if (!sirfport->is_atlas7)
225 			wr_regl(port, ureg->sirfsoc_int_en_reg,
226 				rd_regl(port, ureg->sirfsoc_int_en_reg)|
227 				uint_en->sirfsoc_txfifo_empty_en);
228 		else
229 			wr_regl(port, ureg->sirfsoc_int_en_reg,
230 				uint_en->sirfsoc_txfifo_empty_en);
231 		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
232 	} else {
233 		/* tx transfer mode switch into dma mode */
234 		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
235 		wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
236 			rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl)&
237 			~SIRFUART_IO_MODE);
238 		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
239 		tran_size &= ~(0x3);
240 
241 		sirfport->tx_dma_addr = dma_map_single(port->dev,
242 			xmit->buf + xmit->tail,
243 			tran_size, DMA_TO_DEVICE);
244 		sirfport->tx_dma_desc = dmaengine_prep_slave_single(
245 			sirfport->tx_dma_chan, sirfport->tx_dma_addr,
246 			tran_size, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
247 		if (!sirfport->tx_dma_desc) {
248 			dev_err(port->dev, "DMA prep slave single fail\n");
249 			return;
250 		}
251 		sirfport->tx_dma_desc->callback =
252 			sirfsoc_uart_tx_dma_complete_callback;
253 		sirfport->tx_dma_desc->callback_param = (void *)sirfport;
254 		sirfport->transfer_size = tran_size;
255 
256 		dmaengine_submit(sirfport->tx_dma_desc);
257 		dma_async_issue_pending(sirfport->tx_dma_chan);
258 		sirfport->tx_dma_state = TX_DMA_RUNNING;
259 	}
260 }
261 
sirfsoc_uart_start_tx(struct uart_port * port)262 static void sirfsoc_uart_start_tx(struct uart_port *port)
263 {
264 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
265 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
266 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
267 	if (sirfport->tx_dma_chan)
268 		sirfsoc_uart_tx_with_dma(sirfport);
269 	else {
270 		if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
271 			wr_regl(port, ureg->sirfsoc_tx_rx_en, rd_regl(port,
272 				ureg->sirfsoc_tx_rx_en) | SIRFUART_TX_EN);
273 		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
274 		sirfsoc_uart_pio_tx_chars(sirfport, port->fifosize);
275 		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
276 		if (!sirfport->is_atlas7)
277 			wr_regl(port, ureg->sirfsoc_int_en_reg,
278 					rd_regl(port, ureg->sirfsoc_int_en_reg)|
279 					uint_en->sirfsoc_txfifo_empty_en);
280 		else
281 			wr_regl(port, ureg->sirfsoc_int_en_reg,
282 					uint_en->sirfsoc_txfifo_empty_en);
283 	}
284 }
285 
sirfsoc_uart_stop_rx(struct uart_port * port)286 static void sirfsoc_uart_stop_rx(struct uart_port *port)
287 {
288 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
289 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
290 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
291 
292 	wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
293 	if (sirfport->rx_dma_chan) {
294 		if (!sirfport->is_atlas7)
295 			wr_regl(port, ureg->sirfsoc_int_en_reg,
296 				rd_regl(port, ureg->sirfsoc_int_en_reg) &
297 				~(SIRFUART_RX_DMA_INT_EN(uint_en,
298 				sirfport->uart_reg->uart_type) |
299 				uint_en->sirfsoc_rx_done_en));
300 		else
301 			wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
302 				SIRFUART_RX_DMA_INT_EN(uint_en,
303 				sirfport->uart_reg->uart_type)|
304 				uint_en->sirfsoc_rx_done_en);
305 		dmaengine_terminate_all(sirfport->rx_dma_chan);
306 	} else {
307 		if (!sirfport->is_atlas7)
308 			wr_regl(port, ureg->sirfsoc_int_en_reg,
309 				rd_regl(port, ureg->sirfsoc_int_en_reg)&
310 				~(SIRFUART_RX_IO_INT_EN(uint_en,
311 				sirfport->uart_reg->uart_type)));
312 		else
313 			wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
314 				SIRFUART_RX_IO_INT_EN(uint_en,
315 				sirfport->uart_reg->uart_type));
316 	}
317 }
318 
sirfsoc_uart_disable_ms(struct uart_port * port)319 static void sirfsoc_uart_disable_ms(struct uart_port *port)
320 {
321 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
322 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
323 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
324 
325 	if (!sirfport->hw_flow_ctrl)
326 		return;
327 	sirfport->ms_enabled = false;
328 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
329 		wr_regl(port, ureg->sirfsoc_afc_ctrl,
330 				rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0x3FF);
331 		if (!sirfport->is_atlas7)
332 			wr_regl(port, ureg->sirfsoc_int_en_reg,
333 					rd_regl(port, ureg->sirfsoc_int_en_reg)&
334 					~uint_en->sirfsoc_cts_en);
335 		else
336 			wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
337 					uint_en->sirfsoc_cts_en);
338 	} else
339 		disable_irq(gpio_to_irq(sirfport->cts_gpio));
340 }
341 
sirfsoc_uart_usp_cts_handler(int irq,void * dev_id)342 static irqreturn_t sirfsoc_uart_usp_cts_handler(int irq, void *dev_id)
343 {
344 	struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)dev_id;
345 	struct uart_port *port = &sirfport->port;
346 	spin_lock(&port->lock);
347 	if (gpio_is_valid(sirfport->cts_gpio) && sirfport->ms_enabled)
348 		uart_handle_cts_change(port,
349 				!gpio_get_value(sirfport->cts_gpio));
350 	spin_unlock(&port->lock);
351 	return IRQ_HANDLED;
352 }
353 
sirfsoc_uart_enable_ms(struct uart_port * port)354 static void sirfsoc_uart_enable_ms(struct uart_port *port)
355 {
356 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
357 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
358 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
359 
360 	if (!sirfport->hw_flow_ctrl)
361 		return;
362 	sirfport->ms_enabled = true;
363 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
364 		wr_regl(port, ureg->sirfsoc_afc_ctrl,
365 				rd_regl(port, ureg->sirfsoc_afc_ctrl) |
366 				SIRFUART_AFC_TX_EN | SIRFUART_AFC_RX_EN |
367 				SIRFUART_AFC_CTRL_RX_THD);
368 		if (!sirfport->is_atlas7)
369 			wr_regl(port, ureg->sirfsoc_int_en_reg,
370 					rd_regl(port, ureg->sirfsoc_int_en_reg)
371 					| uint_en->sirfsoc_cts_en);
372 		else
373 			wr_regl(port, ureg->sirfsoc_int_en_reg,
374 					uint_en->sirfsoc_cts_en);
375 	} else
376 		enable_irq(gpio_to_irq(sirfport->cts_gpio));
377 }
378 
sirfsoc_uart_break_ctl(struct uart_port * port,int break_state)379 static void sirfsoc_uart_break_ctl(struct uart_port *port, int break_state)
380 {
381 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
382 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
383 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
384 		unsigned long ulcon = rd_regl(port, ureg->sirfsoc_line_ctrl);
385 		if (break_state)
386 			ulcon |= SIRFUART_SET_BREAK;
387 		else
388 			ulcon &= ~SIRFUART_SET_BREAK;
389 		wr_regl(port, ureg->sirfsoc_line_ctrl, ulcon);
390 	}
391 }
392 
393 static unsigned int
sirfsoc_uart_pio_rx_chars(struct uart_port * port,unsigned int max_rx_count)394 sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count)
395 {
396 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
397 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
398 	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
399 	unsigned int ch, rx_count = 0;
400 	struct tty_struct *tty;
401 	tty = tty_port_tty_get(&port->state->port);
402 	if (!tty)
403 		return -ENODEV;
404 	while (!(rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
405 					ufifo_st->ff_empty(port))) {
406 		ch = rd_regl(port, ureg->sirfsoc_rx_fifo_data) |
407 			SIRFUART_DUMMY_READ;
408 		if (unlikely(uart_handle_sysrq_char(port, ch)))
409 			continue;
410 		uart_insert_char(port, 0, 0, ch, TTY_NORMAL);
411 		rx_count++;
412 		if (rx_count >= max_rx_count)
413 			break;
414 	}
415 
416 	port->icount.rx += rx_count;
417 
418 	return rx_count;
419 }
420 
421 static unsigned int
sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port * sirfport,int count)422 sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port *sirfport, int count)
423 {
424 	struct uart_port *port = &sirfport->port;
425 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
426 	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
427 	struct circ_buf *xmit = &port->state->xmit;
428 	unsigned int num_tx = 0;
429 	while (!uart_circ_empty(xmit) &&
430 		!(rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
431 					ufifo_st->ff_full(port)) &&
432 		count--) {
433 		wr_regl(port, ureg->sirfsoc_tx_fifo_data,
434 				xmit->buf[xmit->tail]);
435 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
436 		port->icount.tx++;
437 		num_tx++;
438 	}
439 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
440 		uart_write_wakeup(port);
441 	return num_tx;
442 }
443 
sirfsoc_uart_tx_dma_complete_callback(void * param)444 static void sirfsoc_uart_tx_dma_complete_callback(void *param)
445 {
446 	struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
447 	struct uart_port *port = &sirfport->port;
448 	struct circ_buf *xmit = &port->state->xmit;
449 	unsigned long flags;
450 
451 	spin_lock_irqsave(&port->lock, flags);
452 	xmit->tail = (xmit->tail + sirfport->transfer_size) &
453 				(UART_XMIT_SIZE - 1);
454 	port->icount.tx += sirfport->transfer_size;
455 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
456 		uart_write_wakeup(port);
457 	if (sirfport->tx_dma_addr)
458 		dma_unmap_single(port->dev, sirfport->tx_dma_addr,
459 				sirfport->transfer_size, DMA_TO_DEVICE);
460 	sirfport->tx_dma_state = TX_DMA_IDLE;
461 	sirfsoc_uart_tx_with_dma(sirfport);
462 	spin_unlock_irqrestore(&port->lock, flags);
463 }
464 
sirfsoc_uart_isr(int irq,void * dev_id)465 static irqreturn_t sirfsoc_uart_isr(int irq, void *dev_id)
466 {
467 	unsigned long intr_status;
468 	unsigned long cts_status;
469 	unsigned long flag = TTY_NORMAL;
470 	struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)dev_id;
471 	struct uart_port *port = &sirfport->port;
472 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
473 	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
474 	struct sirfsoc_int_status *uint_st = &sirfport->uart_reg->uart_int_st;
475 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
476 	struct uart_state *state = port->state;
477 	struct circ_buf *xmit = &port->state->xmit;
478 	spin_lock(&port->lock);
479 	intr_status = rd_regl(port, ureg->sirfsoc_int_st_reg);
480 	wr_regl(port, ureg->sirfsoc_int_st_reg, intr_status);
481 	intr_status &= rd_regl(port, ureg->sirfsoc_int_en_reg);
482 	if (unlikely(intr_status & (SIRFUART_ERR_INT_STAT(uint_st,
483 				sirfport->uart_reg->uart_type)))) {
484 		if (intr_status & uint_st->sirfsoc_rxd_brk) {
485 			port->icount.brk++;
486 			if (uart_handle_break(port))
487 				goto recv_char;
488 		}
489 		if (intr_status & uint_st->sirfsoc_rx_oflow) {
490 			port->icount.overrun++;
491 			flag = TTY_OVERRUN;
492 		}
493 		if (intr_status & uint_st->sirfsoc_frm_err) {
494 			port->icount.frame++;
495 			flag = TTY_FRAME;
496 		}
497 		if (intr_status & uint_st->sirfsoc_parity_err) {
498 			port->icount.parity++;
499 			flag = TTY_PARITY;
500 		}
501 		wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
502 		wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
503 		wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
504 		intr_status &= port->read_status_mask;
505 		uart_insert_char(port, intr_status,
506 					uint_en->sirfsoc_rx_oflow_en, 0, flag);
507 	}
508 recv_char:
509 	if ((sirfport->uart_reg->uart_type == SIRF_REAL_UART) &&
510 			(intr_status & SIRFUART_CTS_INT_ST(uint_st)) &&
511 			!sirfport->tx_dma_state) {
512 		cts_status = rd_regl(port, ureg->sirfsoc_afc_ctrl) &
513 					SIRFUART_AFC_CTS_STATUS;
514 		if (cts_status != 0)
515 			cts_status = 0;
516 		else
517 			cts_status = 1;
518 		uart_handle_cts_change(port, cts_status);
519 		wake_up_interruptible(&state->port.delta_msr_wait);
520 	}
521 	if (!sirfport->rx_dma_chan &&
522 		(intr_status & SIRFUART_RX_IO_INT_ST(uint_st))) {
523 		/*
524 		 * chip will trigger continuous RX_TIMEOUT interrupt
525 		 * in RXFIFO empty and not trigger if RXFIFO recevice
526 		 * data in limit time, original method use RX_TIMEOUT
527 		 * will trigger lots of useless interrupt in RXFIFO
528 		 * empty.RXFIFO received one byte will trigger RX_DONE
529 		 * interrupt.use RX_DONE to wait for data received
530 		 * into RXFIFO, use RX_THD/RX_FULL for lots data receive
531 		 * and use RX_TIMEOUT for the last left data.
532 		 */
533 		if (intr_status & uint_st->sirfsoc_rx_done) {
534 			if (!sirfport->is_atlas7) {
535 				wr_regl(port, ureg->sirfsoc_int_en_reg,
536 					rd_regl(port, ureg->sirfsoc_int_en_reg)
537 					& ~(uint_en->sirfsoc_rx_done_en));
538 				wr_regl(port, ureg->sirfsoc_int_en_reg,
539 				rd_regl(port, ureg->sirfsoc_int_en_reg)
540 				| (uint_en->sirfsoc_rx_timeout_en));
541 			} else {
542 				wr_regl(port, ureg->sirfsoc_int_en_clr_reg,
543 					uint_en->sirfsoc_rx_done_en);
544 				wr_regl(port, ureg->sirfsoc_int_en_reg,
545 					uint_en->sirfsoc_rx_timeout_en);
546 			}
547 		} else {
548 			if (intr_status & uint_st->sirfsoc_rx_timeout) {
549 				if (!sirfport->is_atlas7) {
550 					wr_regl(port, ureg->sirfsoc_int_en_reg,
551 					rd_regl(port, ureg->sirfsoc_int_en_reg)
552 					& ~(uint_en->sirfsoc_rx_timeout_en));
553 					wr_regl(port, ureg->sirfsoc_int_en_reg,
554 					rd_regl(port, ureg->sirfsoc_int_en_reg)
555 					| (uint_en->sirfsoc_rx_done_en));
556 				} else {
557 					wr_regl(port,
558 						ureg->sirfsoc_int_en_clr_reg,
559 						uint_en->sirfsoc_rx_timeout_en);
560 					wr_regl(port, ureg->sirfsoc_int_en_reg,
561 						uint_en->sirfsoc_rx_done_en);
562 				}
563 			}
564 			sirfsoc_uart_pio_rx_chars(port, port->fifosize);
565 		}
566 	}
567 	spin_unlock(&port->lock);
568 	tty_flip_buffer_push(&state->port);
569 	spin_lock(&port->lock);
570 	if (intr_status & uint_st->sirfsoc_txfifo_empty) {
571 		if (sirfport->tx_dma_chan)
572 			sirfsoc_uart_tx_with_dma(sirfport);
573 		else {
574 			if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
575 				spin_unlock(&port->lock);
576 				return IRQ_HANDLED;
577 			} else {
578 				sirfsoc_uart_pio_tx_chars(sirfport,
579 						port->fifosize);
580 				if ((uart_circ_empty(xmit)) &&
581 				(rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
582 				ufifo_st->ff_empty(port)))
583 					sirfsoc_uart_stop_tx(port);
584 			}
585 		}
586 	}
587 	spin_unlock(&port->lock);
588 
589 	return IRQ_HANDLED;
590 }
591 
sirfsoc_uart_rx_dma_complete_callback(void * param)592 static void sirfsoc_uart_rx_dma_complete_callback(void *param)
593 {
594 }
595 
596 /* submit rx dma task into dmaengine */
sirfsoc_uart_start_next_rx_dma(struct uart_port * port)597 static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port)
598 {
599 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
600 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
601 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
602 	wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
603 		rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
604 		~SIRFUART_IO_MODE);
605 	sirfport->rx_dma_items.xmit.tail =
606 		sirfport->rx_dma_items.xmit.head = 0;
607 	sirfport->rx_dma_items.desc =
608 		dmaengine_prep_dma_cyclic(sirfport->rx_dma_chan,
609 		sirfport->rx_dma_items.dma_addr, SIRFSOC_RX_DMA_BUF_SIZE,
610 		SIRFSOC_RX_DMA_BUF_SIZE / 2,
611 		DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
612 	if (IS_ERR_OR_NULL(sirfport->rx_dma_items.desc)) {
613 		dev_err(port->dev, "DMA slave single fail\n");
614 		return;
615 	}
616 	sirfport->rx_dma_items.desc->callback =
617 		sirfsoc_uart_rx_dma_complete_callback;
618 	sirfport->rx_dma_items.desc->callback_param = sirfport;
619 	sirfport->rx_dma_items.cookie =
620 		dmaengine_submit(sirfport->rx_dma_items.desc);
621 	dma_async_issue_pending(sirfport->rx_dma_chan);
622 	if (!sirfport->is_atlas7)
623 		wr_regl(port, ureg->sirfsoc_int_en_reg,
624 				rd_regl(port, ureg->sirfsoc_int_en_reg) |
625 				SIRFUART_RX_DMA_INT_EN(uint_en,
626 				sirfport->uart_reg->uart_type));
627 	else
628 		wr_regl(port, ureg->sirfsoc_int_en_reg,
629 				SIRFUART_RX_DMA_INT_EN(uint_en,
630 				sirfport->uart_reg->uart_type));
631 }
632 
633 static unsigned int
sirfsoc_usp_calc_sample_div(unsigned long set_rate,unsigned long ioclk_rate,unsigned long * sample_reg)634 sirfsoc_usp_calc_sample_div(unsigned long set_rate,
635 		unsigned long ioclk_rate, unsigned long *sample_reg)
636 {
637 	unsigned long min_delta = ~0UL;
638 	unsigned short sample_div;
639 	unsigned long ioclk_div = 0;
640 	unsigned long temp_delta;
641 
642 	for (sample_div = SIRF_USP_MIN_SAMPLE_DIV;
643 			sample_div <= SIRF_MAX_SAMPLE_DIV; sample_div++) {
644 		temp_delta = ioclk_rate -
645 		(ioclk_rate + (set_rate * sample_div) / 2)
646 		/ (set_rate * sample_div) * set_rate * sample_div;
647 
648 		temp_delta = (temp_delta > 0) ? temp_delta : -temp_delta;
649 		if (temp_delta < min_delta) {
650 			ioclk_div = (2 * ioclk_rate /
651 				(set_rate * sample_div) + 1) / 2 - 1;
652 			if (ioclk_div > SIRF_IOCLK_DIV_MAX)
653 				continue;
654 			min_delta = temp_delta;
655 			*sample_reg = sample_div;
656 			if (!temp_delta)
657 				break;
658 		}
659 	}
660 	return ioclk_div;
661 }
662 
663 static unsigned int
sirfsoc_uart_calc_sample_div(unsigned long baud_rate,unsigned long ioclk_rate,unsigned long * set_baud)664 sirfsoc_uart_calc_sample_div(unsigned long baud_rate,
665 			unsigned long ioclk_rate, unsigned long *set_baud)
666 {
667 	unsigned long min_delta = ~0UL;
668 	unsigned short sample_div;
669 	unsigned int regv = 0;
670 	unsigned long ioclk_div;
671 	unsigned long baud_tmp;
672 	int temp_delta;
673 
674 	for (sample_div = SIRF_MIN_SAMPLE_DIV;
675 			sample_div <= SIRF_MAX_SAMPLE_DIV; sample_div++) {
676 		ioclk_div = (ioclk_rate / (baud_rate * (sample_div + 1))) - 1;
677 		if (ioclk_div > SIRF_IOCLK_DIV_MAX)
678 			continue;
679 		baud_tmp = ioclk_rate / ((ioclk_div + 1) * (sample_div + 1));
680 		temp_delta = baud_tmp - baud_rate;
681 		temp_delta = (temp_delta > 0) ? temp_delta : -temp_delta;
682 		if (temp_delta < min_delta) {
683 			regv = regv & (~SIRF_IOCLK_DIV_MASK);
684 			regv = regv | ioclk_div;
685 			regv = regv & (~SIRF_SAMPLE_DIV_MASK);
686 			regv = regv | (sample_div << SIRF_SAMPLE_DIV_SHIFT);
687 			min_delta = temp_delta;
688 			*set_baud = baud_tmp;
689 		}
690 	}
691 	return regv;
692 }
693 
sirfsoc_uart_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)694 static void sirfsoc_uart_set_termios(struct uart_port *port,
695 				       struct ktermios *termios,
696 				       struct ktermios *old)
697 {
698 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
699 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
700 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
701 	unsigned long	config_reg = 0;
702 	unsigned long	baud_rate;
703 	unsigned long	set_baud;
704 	unsigned long	flags;
705 	unsigned long	ic;
706 	unsigned int	clk_div_reg = 0;
707 	unsigned long	txfifo_op_reg, ioclk_rate;
708 	unsigned long	rx_time_out;
709 	int		threshold_div;
710 	u32		data_bit_len, stop_bit_len, len_val;
711 	unsigned long	sample_div_reg = 0xf;
712 	ioclk_rate	= port->uartclk;
713 
714 	switch (termios->c_cflag & CSIZE) {
715 	default:
716 	case CS8:
717 		data_bit_len = 8;
718 		config_reg |= SIRFUART_DATA_BIT_LEN_8;
719 		break;
720 	case CS7:
721 		data_bit_len = 7;
722 		config_reg |= SIRFUART_DATA_BIT_LEN_7;
723 		break;
724 	case CS6:
725 		data_bit_len = 6;
726 		config_reg |= SIRFUART_DATA_BIT_LEN_6;
727 		break;
728 	case CS5:
729 		data_bit_len = 5;
730 		config_reg |= SIRFUART_DATA_BIT_LEN_5;
731 		break;
732 	}
733 	if (termios->c_cflag & CSTOPB) {
734 		config_reg |= SIRFUART_STOP_BIT_LEN_2;
735 		stop_bit_len = 2;
736 	} else
737 		stop_bit_len = 1;
738 
739 	spin_lock_irqsave(&port->lock, flags);
740 	port->read_status_mask = uint_en->sirfsoc_rx_oflow_en;
741 	port->ignore_status_mask = 0;
742 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
743 		if (termios->c_iflag & INPCK)
744 			port->read_status_mask |= uint_en->sirfsoc_frm_err_en |
745 				uint_en->sirfsoc_parity_err_en;
746 	} else {
747 		if (termios->c_iflag & INPCK)
748 			port->read_status_mask |= uint_en->sirfsoc_frm_err_en;
749 	}
750 	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
751 			port->read_status_mask |= uint_en->sirfsoc_rxd_brk_en;
752 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
753 		if (termios->c_iflag & IGNPAR)
754 			port->ignore_status_mask |=
755 				uint_en->sirfsoc_frm_err_en |
756 				uint_en->sirfsoc_parity_err_en;
757 		if (termios->c_cflag & PARENB) {
758 			if (termios->c_cflag & CMSPAR) {
759 				if (termios->c_cflag & PARODD)
760 					config_reg |= SIRFUART_STICK_BIT_MARK;
761 				else
762 					config_reg |= SIRFUART_STICK_BIT_SPACE;
763 			} else {
764 				if (termios->c_cflag & PARODD)
765 					config_reg |= SIRFUART_STICK_BIT_ODD;
766 				else
767 					config_reg |= SIRFUART_STICK_BIT_EVEN;
768 			}
769 		}
770 	} else {
771 		if (termios->c_iflag & IGNPAR)
772 			port->ignore_status_mask |=
773 				uint_en->sirfsoc_frm_err_en;
774 		if (termios->c_cflag & PARENB)
775 			dev_warn(port->dev,
776 					"USP-UART not support parity err\n");
777 	}
778 	if (termios->c_iflag & IGNBRK) {
779 		port->ignore_status_mask |=
780 			uint_en->sirfsoc_rxd_brk_en;
781 		if (termios->c_iflag & IGNPAR)
782 			port->ignore_status_mask |=
783 				uint_en->sirfsoc_rx_oflow_en;
784 	}
785 	if ((termios->c_cflag & CREAD) == 0)
786 		port->ignore_status_mask |= SIRFUART_DUMMY_READ;
787 	/* Hardware Flow Control Settings */
788 	if (UART_ENABLE_MS(port, termios->c_cflag)) {
789 		if (!sirfport->ms_enabled)
790 			sirfsoc_uart_enable_ms(port);
791 	} else {
792 		if (sirfport->ms_enabled)
793 			sirfsoc_uart_disable_ms(port);
794 	}
795 	baud_rate = uart_get_baud_rate(port, termios, old, 0, 4000000);
796 	if (ioclk_rate == 150000000) {
797 		for (ic = 0; ic < SIRF_BAUD_RATE_SUPPORT_NR; ic++)
798 			if (baud_rate == baudrate_to_regv[ic].baud_rate)
799 				clk_div_reg = baudrate_to_regv[ic].reg_val;
800 	}
801 	set_baud = baud_rate;
802 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
803 		if (unlikely(clk_div_reg == 0))
804 			clk_div_reg = sirfsoc_uart_calc_sample_div(baud_rate,
805 					ioclk_rate, &set_baud);
806 		wr_regl(port, ureg->sirfsoc_divisor, clk_div_reg);
807 	} else {
808 		clk_div_reg = sirfsoc_usp_calc_sample_div(baud_rate,
809 				ioclk_rate, &sample_div_reg);
810 		sample_div_reg--;
811 		set_baud = ((ioclk_rate / (clk_div_reg+1) - 1) /
812 				(sample_div_reg + 1));
813 		/* setting usp mode 2 */
814 		len_val = ((1 << SIRFSOC_USP_MODE2_RXD_DELAY_OFFSET) |
815 				(1 << SIRFSOC_USP_MODE2_TXD_DELAY_OFFSET));
816 		len_val |= ((clk_div_reg & SIRFSOC_USP_MODE2_CLK_DIVISOR_MASK)
817 				<< SIRFSOC_USP_MODE2_CLK_DIVISOR_OFFSET);
818 		wr_regl(port, ureg->sirfsoc_mode2, len_val);
819 	}
820 	if (tty_termios_baud_rate(termios))
821 		tty_termios_encode_baud_rate(termios, set_baud, set_baud);
822 	/* set receive timeout && data bits len */
823 	rx_time_out = SIRFSOC_UART_RX_TIMEOUT(set_baud, 20000);
824 	rx_time_out = SIRFUART_RECV_TIMEOUT_VALUE(rx_time_out);
825 	txfifo_op_reg = rd_regl(port, ureg->sirfsoc_tx_fifo_op);
826 	wr_regl(port, ureg->sirfsoc_tx_fifo_op,
827 			(txfifo_op_reg & ~SIRFUART_FIFO_START));
828 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
829 		config_reg |= SIRFUART_UART_RECV_TIMEOUT(rx_time_out);
830 		wr_regl(port, ureg->sirfsoc_line_ctrl, config_reg);
831 	} else {
832 		/*tx frame ctrl*/
833 		len_val = (data_bit_len - 1) << SIRFSOC_USP_TX_DATA_LEN_OFFSET;
834 		len_val |= (data_bit_len + 1 + stop_bit_len - 1) <<
835 				SIRFSOC_USP_TX_FRAME_LEN_OFFSET;
836 		len_val |= ((data_bit_len - 1) <<
837 				SIRFSOC_USP_TX_SHIFTER_LEN_OFFSET);
838 		len_val |= (((clk_div_reg & 0xc00) >> 10) <<
839 				SIRFSOC_USP_TX_CLK_DIVISOR_OFFSET);
840 		wr_regl(port, ureg->sirfsoc_tx_frame_ctrl, len_val);
841 		/*rx frame ctrl*/
842 		len_val = (data_bit_len - 1) << SIRFSOC_USP_RX_DATA_LEN_OFFSET;
843 		len_val |= (data_bit_len + 1 + stop_bit_len - 1) <<
844 				SIRFSOC_USP_RX_FRAME_LEN_OFFSET;
845 		len_val |= (data_bit_len - 1) <<
846 				SIRFSOC_USP_RX_SHIFTER_LEN_OFFSET;
847 		len_val |= (((clk_div_reg & 0xf000) >> 12) <<
848 				SIRFSOC_USP_RX_CLK_DIVISOR_OFFSET);
849 		wr_regl(port, ureg->sirfsoc_rx_frame_ctrl, len_val);
850 		/*async param*/
851 		wr_regl(port, ureg->sirfsoc_async_param_reg,
852 			(SIRFUART_USP_RECV_TIMEOUT(rx_time_out)) |
853 			(sample_div_reg & SIRFSOC_USP_ASYNC_DIV2_MASK) <<
854 			SIRFSOC_USP_ASYNC_DIV2_OFFSET);
855 	}
856 	if (sirfport->tx_dma_chan)
857 		wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl, SIRFUART_DMA_MODE);
858 	else
859 		wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl, SIRFUART_IO_MODE);
860 	if (sirfport->rx_dma_chan)
861 		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
862 			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
863 			~SIRFUART_IO_MODE);
864 	else
865 		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
866 			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
867 			SIRFUART_IO_MODE);
868 	sirfport->rx_period_time = 20000000;
869 	/* Reset Rx/Tx FIFO Threshold level for proper baudrate */
870 	if (set_baud < 1000000)
871 		threshold_div = 1;
872 	else
873 		threshold_div = 2;
874 	wr_regl(port, ureg->sirfsoc_tx_fifo_ctrl,
875 				SIRFUART_FIFO_THD(port) / threshold_div);
876 	wr_regl(port, ureg->sirfsoc_rx_fifo_ctrl,
877 				SIRFUART_FIFO_THD(port) / threshold_div);
878 	txfifo_op_reg |= SIRFUART_FIFO_START;
879 	wr_regl(port, ureg->sirfsoc_tx_fifo_op, txfifo_op_reg);
880 	uart_update_timeout(port, termios->c_cflag, set_baud);
881 	wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_TX_EN | SIRFUART_RX_EN);
882 	spin_unlock_irqrestore(&port->lock, flags);
883 }
884 
sirfsoc_uart_pm(struct uart_port * port,unsigned int state,unsigned int oldstate)885 static void sirfsoc_uart_pm(struct uart_port *port, unsigned int state,
886 			      unsigned int oldstate)
887 {
888 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
889 	if (!state)
890 		clk_prepare_enable(sirfport->clk);
891 	else
892 		clk_disable_unprepare(sirfport->clk);
893 }
894 
sirfsoc_uart_startup(struct uart_port * port)895 static int sirfsoc_uart_startup(struct uart_port *port)
896 {
897 	struct sirfsoc_uart_port *sirfport	= to_sirfport(port);
898 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
899 	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
900 	unsigned int index			= port->line;
901 	int ret;
902 	irq_modify_status(port->irq, IRQ_NOREQUEST, IRQ_NOAUTOEN);
903 	ret = request_irq(port->irq,
904 				sirfsoc_uart_isr,
905 				0,
906 				SIRFUART_PORT_NAME,
907 				sirfport);
908 	if (ret != 0) {
909 		dev_err(port->dev, "UART%d request IRQ line (%d) failed.\n",
910 							index, port->irq);
911 		goto irq_err;
912 	}
913 	/* initial hardware settings */
914 	wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
915 		rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl) |
916 		SIRFUART_IO_MODE);
917 	wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
918 		rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
919 		SIRFUART_IO_MODE);
920 	wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
921 		rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
922 		~SIRFUART_RX_DMA_FLUSH);
923 	wr_regl(port, ureg->sirfsoc_tx_dma_io_len, 0);
924 	wr_regl(port, ureg->sirfsoc_rx_dma_io_len, 0);
925 	wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_RX_EN | SIRFUART_TX_EN);
926 	if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
927 		wr_regl(port, ureg->sirfsoc_mode1,
928 			SIRFSOC_USP_ENDIAN_CTRL_LSBF |
929 			SIRFSOC_USP_EN);
930 	wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_RESET);
931 	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
932 	wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
933 	wr_regl(port, ureg->sirfsoc_tx_fifo_ctrl, SIRFUART_FIFO_THD(port));
934 	wr_regl(port, ureg->sirfsoc_rx_fifo_ctrl, SIRFUART_FIFO_THD(port));
935 	if (sirfport->rx_dma_chan)
936 		wr_regl(port, ureg->sirfsoc_rx_fifo_level_chk,
937 			SIRFUART_RX_FIFO_CHK_SC(port->line, 0x1) |
938 			SIRFUART_RX_FIFO_CHK_LC(port->line, 0x2) |
939 			SIRFUART_RX_FIFO_CHK_HC(port->line, 0x4));
940 	if (sirfport->tx_dma_chan) {
941 		sirfport->tx_dma_state = TX_DMA_IDLE;
942 		wr_regl(port, ureg->sirfsoc_tx_fifo_level_chk,
943 				SIRFUART_TX_FIFO_CHK_SC(port->line, 0x1b) |
944 				SIRFUART_TX_FIFO_CHK_LC(port->line, 0xe) |
945 				SIRFUART_TX_FIFO_CHK_HC(port->line, 0x4));
946 	}
947 	sirfport->ms_enabled = false;
948 	if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
949 		sirfport->hw_flow_ctrl) {
950 		irq_modify_status(gpio_to_irq(sirfport->cts_gpio),
951 			IRQ_NOREQUEST, IRQ_NOAUTOEN);
952 		ret = request_irq(gpio_to_irq(sirfport->cts_gpio),
953 			sirfsoc_uart_usp_cts_handler, IRQF_TRIGGER_FALLING |
954 			IRQF_TRIGGER_RISING, "usp_cts_irq", sirfport);
955 		if (ret != 0) {
956 			dev_err(port->dev, "UART-USP:request gpio irq fail\n");
957 			goto init_rx_err;
958 		}
959 	}
960 	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART &&
961 		sirfport->rx_dma_chan)
962 		wr_regl(port, ureg->sirfsoc_swh_dma_io,
963 			SIRFUART_CLEAR_RX_ADDR_EN);
964 	if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
965 			sirfport->rx_dma_chan)
966 		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
967 			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
968 			SIRFSOC_USP_FRADDR_CLR_EN);
969 	if (sirfport->rx_dma_chan && !sirfport->is_hrt_enabled) {
970 		sirfport->is_hrt_enabled = true;
971 		sirfport->rx_period_time = 20000000;
972 		sirfport->rx_last_pos = -1;
973 		sirfport->pio_fetch_cnt = 0;
974 		sirfport->rx_dma_items.xmit.tail =
975 			sirfport->rx_dma_items.xmit.head = 0;
976 		hrtimer_start(&sirfport->hrt,
977 			ns_to_ktime(sirfport->rx_period_time),
978 			HRTIMER_MODE_REL);
979 	}
980 	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
981 	if (sirfport->rx_dma_chan)
982 		sirfsoc_uart_start_next_rx_dma(port);
983 	else {
984 		if (!sirfport->is_atlas7)
985 			wr_regl(port, ureg->sirfsoc_int_en_reg,
986 				rd_regl(port, ureg->sirfsoc_int_en_reg) |
987 				SIRFUART_RX_IO_INT_EN(uint_en,
988 					sirfport->uart_reg->uart_type));
989 		else
990 			wr_regl(port, ureg->sirfsoc_int_en_reg,
991 				SIRFUART_RX_IO_INT_EN(uint_en,
992 					sirfport->uart_reg->uart_type));
993 	}
994 	enable_irq(port->irq);
995 
996 	return 0;
997 init_rx_err:
998 	free_irq(port->irq, sirfport);
999 irq_err:
1000 	return ret;
1001 }
1002 
sirfsoc_uart_shutdown(struct uart_port * port)1003 static void sirfsoc_uart_shutdown(struct uart_port *port)
1004 {
1005 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
1006 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
1007 	struct circ_buf *xmit;
1008 
1009 	xmit = &sirfport->rx_dma_items.xmit;
1010 	if (!sirfport->is_atlas7)
1011 		wr_regl(port, ureg->sirfsoc_int_en_reg, 0);
1012 	else
1013 		wr_regl(port, ureg->sirfsoc_int_en_clr_reg, ~0UL);
1014 
1015 	free_irq(port->irq, sirfport);
1016 	if (sirfport->ms_enabled)
1017 		sirfsoc_uart_disable_ms(port);
1018 	if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
1019 			sirfport->hw_flow_ctrl) {
1020 		gpio_set_value(sirfport->rts_gpio, 1);
1021 		free_irq(gpio_to_irq(sirfport->cts_gpio), sirfport);
1022 	}
1023 	if (sirfport->tx_dma_chan)
1024 		sirfport->tx_dma_state = TX_DMA_IDLE;
1025 	if (sirfport->rx_dma_chan && sirfport->is_hrt_enabled) {
1026 		while (((rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
1027 			SIRFUART_RX_FIFO_MASK) > sirfport->pio_fetch_cnt) &&
1028 			!CIRC_CNT(xmit->head, xmit->tail,
1029 			SIRFSOC_RX_DMA_BUF_SIZE))
1030 			;
1031 		sirfport->is_hrt_enabled = false;
1032 		hrtimer_cancel(&sirfport->hrt);
1033 	}
1034 }
1035 
sirfsoc_uart_type(struct uart_port * port)1036 static const char *sirfsoc_uart_type(struct uart_port *port)
1037 {
1038 	return port->type == SIRFSOC_PORT_TYPE ? SIRFUART_PORT_NAME : NULL;
1039 }
1040 
sirfsoc_uart_request_port(struct uart_port * port)1041 static int sirfsoc_uart_request_port(struct uart_port *port)
1042 {
1043 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
1044 	struct sirfsoc_uart_param *uart_param = &sirfport->uart_reg->uart_param;
1045 	void *ret;
1046 	ret = request_mem_region(port->mapbase,
1047 		SIRFUART_MAP_SIZE, uart_param->port_name);
1048 	return ret ? 0 : -EBUSY;
1049 }
1050 
sirfsoc_uart_release_port(struct uart_port * port)1051 static void sirfsoc_uart_release_port(struct uart_port *port)
1052 {
1053 	release_mem_region(port->mapbase, SIRFUART_MAP_SIZE);
1054 }
1055 
sirfsoc_uart_config_port(struct uart_port * port,int flags)1056 static void sirfsoc_uart_config_port(struct uart_port *port, int flags)
1057 {
1058 	if (flags & UART_CONFIG_TYPE) {
1059 		port->type = SIRFSOC_PORT_TYPE;
1060 		sirfsoc_uart_request_port(port);
1061 	}
1062 }
1063 
1064 static struct uart_ops sirfsoc_uart_ops = {
1065 	.tx_empty	= sirfsoc_uart_tx_empty,
1066 	.get_mctrl	= sirfsoc_uart_get_mctrl,
1067 	.set_mctrl	= sirfsoc_uart_set_mctrl,
1068 	.stop_tx	= sirfsoc_uart_stop_tx,
1069 	.start_tx	= sirfsoc_uart_start_tx,
1070 	.stop_rx	= sirfsoc_uart_stop_rx,
1071 	.enable_ms	= sirfsoc_uart_enable_ms,
1072 	.break_ctl	= sirfsoc_uart_break_ctl,
1073 	.startup	= sirfsoc_uart_startup,
1074 	.shutdown	= sirfsoc_uart_shutdown,
1075 	.set_termios	= sirfsoc_uart_set_termios,
1076 	.pm		= sirfsoc_uart_pm,
1077 	.type		= sirfsoc_uart_type,
1078 	.release_port	= sirfsoc_uart_release_port,
1079 	.request_port	= sirfsoc_uart_request_port,
1080 	.config_port	= sirfsoc_uart_config_port,
1081 };
1082 
1083 #ifdef CONFIG_SERIAL_SIRFSOC_CONSOLE
1084 static int __init
sirfsoc_uart_console_setup(struct console * co,char * options)1085 sirfsoc_uart_console_setup(struct console *co, char *options)
1086 {
1087 	unsigned int baud = 115200;
1088 	unsigned int bits = 8;
1089 	unsigned int parity = 'n';
1090 	unsigned int flow = 'n';
1091 	struct sirfsoc_uart_port *sirfport;
1092 	struct sirfsoc_register *ureg;
1093 	if (co->index < 0 || co->index >= SIRFSOC_UART_NR)
1094 		co->index = 1;
1095 	sirfport = sirf_ports[co->index];
1096 	if (!sirfport)
1097 		return -ENODEV;
1098 	ureg = &sirfport->uart_reg->uart_reg;
1099 	if (!sirfport->port.mapbase)
1100 		return -ENODEV;
1101 
1102 	/* enable usp in mode1 register */
1103 	if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
1104 		wr_regl(&sirfport->port, ureg->sirfsoc_mode1, SIRFSOC_USP_EN |
1105 				SIRFSOC_USP_ENDIAN_CTRL_LSBF);
1106 	if (options)
1107 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1108 	sirfport->port.cons = co;
1109 
1110 	/* default console tx/rx transfer using io mode */
1111 	sirfport->rx_dma_chan = NULL;
1112 	sirfport->tx_dma_chan = NULL;
1113 	return uart_set_options(&sirfport->port, co, baud, parity, bits, flow);
1114 }
1115 
sirfsoc_uart_console_putchar(struct uart_port * port,int ch)1116 static void sirfsoc_uart_console_putchar(struct uart_port *port, int ch)
1117 {
1118 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
1119 	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
1120 	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
1121 	while (rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
1122 		ufifo_st->ff_full(port))
1123 		cpu_relax();
1124 	wr_regl(port, ureg->sirfsoc_tx_fifo_data, ch);
1125 }
1126 
sirfsoc_uart_console_write(struct console * co,const char * s,unsigned int count)1127 static void sirfsoc_uart_console_write(struct console *co, const char *s,
1128 							unsigned int count)
1129 {
1130 	struct sirfsoc_uart_port *sirfport = sirf_ports[co->index];
1131 
1132 	uart_console_write(&sirfport->port, s, count,
1133 			sirfsoc_uart_console_putchar);
1134 }
1135 
1136 static struct console sirfsoc_uart_console = {
1137 	.name		= SIRFSOC_UART_NAME,
1138 	.device		= uart_console_device,
1139 	.flags		= CON_PRINTBUFFER,
1140 	.index		= -1,
1141 	.write		= sirfsoc_uart_console_write,
1142 	.setup		= sirfsoc_uart_console_setup,
1143 	.data           = &sirfsoc_uart_drv,
1144 };
1145 
sirfsoc_uart_console_init(void)1146 static int __init sirfsoc_uart_console_init(void)
1147 {
1148 	register_console(&sirfsoc_uart_console);
1149 	return 0;
1150 }
1151 console_initcall(sirfsoc_uart_console_init);
1152 #endif
1153 
1154 static struct uart_driver sirfsoc_uart_drv = {
1155 	.owner		= THIS_MODULE,
1156 	.driver_name	= SIRFUART_PORT_NAME,
1157 	.nr		= SIRFSOC_UART_NR,
1158 	.dev_name	= SIRFSOC_UART_NAME,
1159 	.major		= SIRFSOC_UART_MAJOR,
1160 	.minor		= SIRFSOC_UART_MINOR,
1161 #ifdef CONFIG_SERIAL_SIRFSOC_CONSOLE
1162 	.cons			= &sirfsoc_uart_console,
1163 #else
1164 	.cons			= NULL,
1165 #endif
1166 };
1167 
1168 static enum hrtimer_restart
sirfsoc_uart_rx_dma_hrtimer_callback(struct hrtimer * hrt)1169 	sirfsoc_uart_rx_dma_hrtimer_callback(struct hrtimer *hrt)
1170 {
1171 	struct sirfsoc_uart_port *sirfport;
1172 	struct uart_port *port;
1173 	int count, inserted;
1174 	struct dma_tx_state tx_state;
1175 	struct tty_struct *tty;
1176 	struct sirfsoc_register *ureg;
1177 	struct circ_buf *xmit;
1178 	struct sirfsoc_fifo_status *ufifo_st;
1179 	int max_pio_cnt;
1180 
1181 	sirfport = container_of(hrt, struct sirfsoc_uart_port, hrt);
1182 	port = &sirfport->port;
1183 	inserted = 0;
1184 	tty = port->state->port.tty;
1185 	ureg = &sirfport->uart_reg->uart_reg;
1186 	xmit = &sirfport->rx_dma_items.xmit;
1187 	ufifo_st = &sirfport->uart_reg->fifo_status;
1188 
1189 	dmaengine_tx_status(sirfport->rx_dma_chan,
1190 			sirfport->rx_dma_items.cookie, &tx_state);
1191 	if (SIRFSOC_RX_DMA_BUF_SIZE - tx_state.residue !=
1192 		sirfport->rx_last_pos) {
1193 		xmit->head = SIRFSOC_RX_DMA_BUF_SIZE - tx_state.residue;
1194 		sirfport->rx_last_pos = xmit->head;
1195 		sirfport->pio_fetch_cnt = 0;
1196 	}
1197 	count = CIRC_CNT_TO_END(xmit->head, xmit->tail,
1198 			SIRFSOC_RX_DMA_BUF_SIZE);
1199 	while (count > 0) {
1200 		inserted = tty_insert_flip_string(tty->port,
1201 			(const unsigned char *)&xmit->buf[xmit->tail], count);
1202 		if (!inserted)
1203 			goto next_hrt;
1204 		port->icount.rx += inserted;
1205 		xmit->tail = (xmit->tail + inserted) &
1206 				(SIRFSOC_RX_DMA_BUF_SIZE - 1);
1207 		count = CIRC_CNT_TO_END(xmit->head, xmit->tail,
1208 				SIRFSOC_RX_DMA_BUF_SIZE);
1209 		tty_flip_buffer_push(tty->port);
1210 	}
1211 	/*
1212 	 * if RX DMA buffer data have all push into tty buffer, and there is
1213 	 * only little data(less than a dma transfer unit) left in rxfifo,
1214 	 * fetch it out in pio mode and switch back to dma immediately
1215 	 */
1216 	if (!inserted && !count &&
1217 		((rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
1218 		SIRFUART_RX_FIFO_MASK) > sirfport->pio_fetch_cnt)) {
1219 		dmaengine_pause(sirfport->rx_dma_chan);
1220 		/* switch to pio mode */
1221 		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
1222 			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
1223 			SIRFUART_IO_MODE);
1224 		/*
1225 		 * UART controller SWH_DMA_IO register have CLEAR_RX_ADDR_EN
1226 		 * When found changing I/O to DMA mode, it clears
1227 		 * two low bits of read point;
1228 		 * USP have similar FRADDR_CLR_EN bit in USP_RX_DMA_IO_CTRL.
1229 		 * Fetch data out from rxfifo into DMA buffer in PIO mode,
1230 		 * while switch back to DMA mode, the data fetched will override
1231 		 * by DMA, as hardware have a strange behaviour:
1232 		 * after switch back to DMA mode, check rxfifo status it will
1233 		 * be the number PIO fetched, so record the fetched data count
1234 		 * to avoid the repeated fetch
1235 		 */
1236 		max_pio_cnt = 3;
1237 		while (!(rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
1238 			ufifo_st->ff_empty(port)) && max_pio_cnt--) {
1239 			xmit->buf[xmit->head] =
1240 				rd_regl(port, ureg->sirfsoc_rx_fifo_data);
1241 			xmit->head = (xmit->head + 1) &
1242 					(SIRFSOC_RX_DMA_BUF_SIZE - 1);
1243 			sirfport->pio_fetch_cnt++;
1244 		}
1245 		/* switch back to dma mode */
1246 		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
1247 			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
1248 			~SIRFUART_IO_MODE);
1249 		dmaengine_resume(sirfport->rx_dma_chan);
1250 	}
1251 next_hrt:
1252 	hrtimer_forward_now(hrt, ns_to_ktime(sirfport->rx_period_time));
1253 	return HRTIMER_RESTART;
1254 }
1255 
1256 static struct of_device_id sirfsoc_uart_ids[] = {
1257 	{ .compatible = "sirf,prima2-uart", .data = &sirfsoc_uart,},
1258 	{ .compatible = "sirf,atlas7-uart", .data = &sirfsoc_uart},
1259 	{ .compatible = "sirf,prima2-usp-uart", .data = &sirfsoc_usp},
1260 	{ .compatible = "sirf,atlas7-usp-uart", .data = &sirfsoc_usp},
1261 	{}
1262 };
1263 MODULE_DEVICE_TABLE(of, sirfsoc_uart_ids);
1264 
sirfsoc_uart_probe(struct platform_device * pdev)1265 static int sirfsoc_uart_probe(struct platform_device *pdev)
1266 {
1267 	struct sirfsoc_uart_port *sirfport;
1268 	struct uart_port *port;
1269 	struct resource *res;
1270 	int ret;
1271 	struct dma_slave_config slv_cfg = {
1272 		.src_maxburst = 1,
1273 	};
1274 	struct dma_slave_config tx_slv_cfg = {
1275 		.dst_maxburst = 2,
1276 	};
1277 	const struct of_device_id *match;
1278 
1279 	match = of_match_node(sirfsoc_uart_ids, pdev->dev.of_node);
1280 	sirfport = devm_kzalloc(&pdev->dev, sizeof(*sirfport), GFP_KERNEL);
1281 	if (!sirfport) {
1282 		ret = -ENOMEM;
1283 		goto err;
1284 	}
1285 	sirfport->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
1286 	sirf_ports[sirfport->port.line] = sirfport;
1287 	sirfport->port.iotype = UPIO_MEM;
1288 	sirfport->port.flags = UPF_BOOT_AUTOCONF;
1289 	port = &sirfport->port;
1290 	port->dev = &pdev->dev;
1291 	port->private_data = sirfport;
1292 	sirfport->uart_reg = (struct sirfsoc_uart_register *)match->data;
1293 
1294 	sirfport->hw_flow_ctrl = of_property_read_bool(pdev->dev.of_node,
1295 		"sirf,uart-has-rtscts");
1296 	if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-uart") ||
1297 		of_device_is_compatible(pdev->dev.of_node, "sirf,atlas7-uart"))
1298 		sirfport->uart_reg->uart_type = SIRF_REAL_UART;
1299 	if (of_device_is_compatible(pdev->dev.of_node,
1300 		"sirf,prima2-usp-uart") || of_device_is_compatible(
1301 		pdev->dev.of_node, "sirf,atlas7-usp-uart")) {
1302 		sirfport->uart_reg->uart_type =	SIRF_USP_UART;
1303 		if (!sirfport->hw_flow_ctrl)
1304 			goto usp_no_flow_control;
1305 		if (of_find_property(pdev->dev.of_node, "cts-gpios", NULL))
1306 			sirfport->cts_gpio = of_get_named_gpio(
1307 					pdev->dev.of_node, "cts-gpios", 0);
1308 		else
1309 			sirfport->cts_gpio = -1;
1310 		if (of_find_property(pdev->dev.of_node, "rts-gpios", NULL))
1311 			sirfport->rts_gpio = of_get_named_gpio(
1312 					pdev->dev.of_node, "rts-gpios", 0);
1313 		else
1314 			sirfport->rts_gpio = -1;
1315 
1316 		if ((!gpio_is_valid(sirfport->cts_gpio) ||
1317 			 !gpio_is_valid(sirfport->rts_gpio))) {
1318 			ret = -EINVAL;
1319 			dev_err(&pdev->dev,
1320 				"Usp flow control must have cts and rts gpio");
1321 			goto err;
1322 		}
1323 		ret = devm_gpio_request(&pdev->dev, sirfport->cts_gpio,
1324 				"usp-cts-gpio");
1325 		if (ret) {
1326 			dev_err(&pdev->dev, "Unable request cts gpio");
1327 			goto err;
1328 		}
1329 		gpio_direction_input(sirfport->cts_gpio);
1330 		ret = devm_gpio_request(&pdev->dev, sirfport->rts_gpio,
1331 				"usp-rts-gpio");
1332 		if (ret) {
1333 			dev_err(&pdev->dev, "Unable request rts gpio");
1334 			goto err;
1335 		}
1336 		gpio_direction_output(sirfport->rts_gpio, 1);
1337 	}
1338 usp_no_flow_control:
1339 	if (of_device_is_compatible(pdev->dev.of_node, "sirf,atlas7-uart") ||
1340 	    of_device_is_compatible(pdev->dev.of_node, "sirf,atlas7-usp-uart"))
1341 		sirfport->is_atlas7 = true;
1342 
1343 	if (of_property_read_u32(pdev->dev.of_node,
1344 			"fifosize",
1345 			&port->fifosize)) {
1346 		dev_err(&pdev->dev,
1347 			"Unable to find fifosize in uart node.\n");
1348 		ret = -EFAULT;
1349 		goto err;
1350 	}
1351 
1352 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1353 	if (res == NULL) {
1354 		dev_err(&pdev->dev, "Insufficient resources.\n");
1355 		ret = -EFAULT;
1356 		goto err;
1357 	}
1358 	port->mapbase = res->start;
1359 	port->membase = devm_ioremap(&pdev->dev,
1360 			res->start, resource_size(res));
1361 	if (!port->membase) {
1362 		dev_err(&pdev->dev, "Cannot remap resource.\n");
1363 		ret = -ENOMEM;
1364 		goto err;
1365 	}
1366 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1367 	if (res == NULL) {
1368 		dev_err(&pdev->dev, "Insufficient resources.\n");
1369 		ret = -EFAULT;
1370 		goto err;
1371 	}
1372 	port->irq = res->start;
1373 
1374 	sirfport->clk = devm_clk_get(&pdev->dev, NULL);
1375 	if (IS_ERR(sirfport->clk)) {
1376 		ret = PTR_ERR(sirfport->clk);
1377 		goto err;
1378 	}
1379 	port->uartclk = clk_get_rate(sirfport->clk);
1380 
1381 	port->ops = &sirfsoc_uart_ops;
1382 	spin_lock_init(&port->lock);
1383 
1384 	platform_set_drvdata(pdev, sirfport);
1385 	ret = uart_add_one_port(&sirfsoc_uart_drv, port);
1386 	if (ret != 0) {
1387 		dev_err(&pdev->dev, "Cannot add UART port(%d).\n", pdev->id);
1388 		goto err;
1389 	}
1390 
1391 	sirfport->rx_dma_chan = dma_request_slave_channel(port->dev, "rx");
1392 	sirfport->rx_dma_items.xmit.buf =
1393 		dma_alloc_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
1394 		&sirfport->rx_dma_items.dma_addr, GFP_KERNEL);
1395 	if (!sirfport->rx_dma_items.xmit.buf) {
1396 		dev_err(port->dev, "Uart alloc bufa failed\n");
1397 		ret = -ENOMEM;
1398 		goto alloc_coherent_err;
1399 	}
1400 	sirfport->rx_dma_items.xmit.head =
1401 		sirfport->rx_dma_items.xmit.tail = 0;
1402 	if (sirfport->rx_dma_chan)
1403 		dmaengine_slave_config(sirfport->rx_dma_chan, &slv_cfg);
1404 	sirfport->tx_dma_chan = dma_request_slave_channel(port->dev, "tx");
1405 	if (sirfport->tx_dma_chan)
1406 		dmaengine_slave_config(sirfport->tx_dma_chan, &tx_slv_cfg);
1407 	if (sirfport->rx_dma_chan) {
1408 		hrtimer_init(&sirfport->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1409 		sirfport->hrt.function = sirfsoc_uart_rx_dma_hrtimer_callback;
1410 		sirfport->is_hrt_enabled = false;
1411 	}
1412 
1413 	return 0;
1414 alloc_coherent_err:
1415 	dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
1416 			sirfport->rx_dma_items.xmit.buf,
1417 			sirfport->rx_dma_items.dma_addr);
1418 	dma_release_channel(sirfport->rx_dma_chan);
1419 err:
1420 	return ret;
1421 }
1422 
sirfsoc_uart_remove(struct platform_device * pdev)1423 static int sirfsoc_uart_remove(struct platform_device *pdev)
1424 {
1425 	struct sirfsoc_uart_port *sirfport = platform_get_drvdata(pdev);
1426 	struct uart_port *port = &sirfport->port;
1427 	uart_remove_one_port(&sirfsoc_uart_drv, port);
1428 	if (sirfport->rx_dma_chan) {
1429 		dmaengine_terminate_all(sirfport->rx_dma_chan);
1430 		dma_release_channel(sirfport->rx_dma_chan);
1431 		dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
1432 				sirfport->rx_dma_items.xmit.buf,
1433 				sirfport->rx_dma_items.dma_addr);
1434 	}
1435 	if (sirfport->tx_dma_chan) {
1436 		dmaengine_terminate_all(sirfport->tx_dma_chan);
1437 		dma_release_channel(sirfport->tx_dma_chan);
1438 	}
1439 	return 0;
1440 }
1441 
1442 #ifdef CONFIG_PM_SLEEP
1443 static int
sirfsoc_uart_suspend(struct device * pdev)1444 sirfsoc_uart_suspend(struct device *pdev)
1445 {
1446 	struct sirfsoc_uart_port *sirfport = dev_get_drvdata(pdev);
1447 	struct uart_port *port = &sirfport->port;
1448 	uart_suspend_port(&sirfsoc_uart_drv, port);
1449 	return 0;
1450 }
1451 
sirfsoc_uart_resume(struct device * pdev)1452 static int sirfsoc_uart_resume(struct device *pdev)
1453 {
1454 	struct sirfsoc_uart_port *sirfport = dev_get_drvdata(pdev);
1455 	struct uart_port *port = &sirfport->port;
1456 	uart_resume_port(&sirfsoc_uart_drv, port);
1457 	return 0;
1458 }
1459 #endif
1460 
1461 static const struct dev_pm_ops sirfsoc_uart_pm_ops = {
1462 	SET_SYSTEM_SLEEP_PM_OPS(sirfsoc_uart_suspend, sirfsoc_uart_resume)
1463 };
1464 
1465 static struct platform_driver sirfsoc_uart_driver = {
1466 	.probe		= sirfsoc_uart_probe,
1467 	.remove		= sirfsoc_uart_remove,
1468 	.driver		= {
1469 		.name	= SIRFUART_PORT_NAME,
1470 		.of_match_table = sirfsoc_uart_ids,
1471 		.pm	= &sirfsoc_uart_pm_ops,
1472 	},
1473 };
1474 
sirfsoc_uart_init(void)1475 static int __init sirfsoc_uart_init(void)
1476 {
1477 	int ret = 0;
1478 
1479 	ret = uart_register_driver(&sirfsoc_uart_drv);
1480 	if (ret)
1481 		goto out;
1482 
1483 	ret = platform_driver_register(&sirfsoc_uart_driver);
1484 	if (ret)
1485 		uart_unregister_driver(&sirfsoc_uart_drv);
1486 out:
1487 	return ret;
1488 }
1489 module_init(sirfsoc_uart_init);
1490 
sirfsoc_uart_exit(void)1491 static void __exit sirfsoc_uart_exit(void)
1492 {
1493 	platform_driver_unregister(&sirfsoc_uart_driver);
1494 	uart_unregister_driver(&sirfsoc_uart_drv);
1495 }
1496 module_exit(sirfsoc_uart_exit);
1497 
1498 MODULE_LICENSE("GPL v2");
1499 MODULE_AUTHOR("Bin Shi <Bin.Shi@csr.com>, Rong Wang<Rong.Wang@csr.com>");
1500 MODULE_DESCRIPTION("CSR SiRFprimaII Uart Driver");
1501