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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
32static unsigned int
33sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port *sirfport, int count);
34static unsigned int
35sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count);
36static struct uart_driver sirfsoc_uart_drv;
37
38static void sirfsoc_uart_tx_dma_complete_callback(void *param);
39static 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
60static struct sirfsoc_uart_port *sirf_ports[SIRFSOC_UART_NR];
61
62static inline struct sirfsoc_uart_port *to_sirfport(struct uart_port *port)
63{
64 return container_of(port, struct sirfsoc_uart_port, port);
65}
66
67static 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
77static 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 }
95cts_deasserted:
96 return TIOCM_CAR | TIOCM_DSR;
97cts_asserted:
98 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
99}
100
101static 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
143static 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
176static 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
262static 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
286static 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
319static 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
342static 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
354static 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
379static 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
393static unsigned int
394sirfsoc_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
421static unsigned int
422sirfsoc_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
444static 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
465static 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 }
508recv_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
592static void sirfsoc_uart_rx_dma_complete_callback(void *param)
593{
594}
595
596/* submit rx dma task into dmaengine */
597static 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
633static unsigned int
634sirfsoc_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
663static unsigned int
664sirfsoc_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
694static 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
885static 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
895static 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;
997init_rx_err:
998 free_irq(port->irq, sirfport);
999irq_err:
1000 return ret;
1001}
1002
1003static 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
1036static const char *sirfsoc_uart_type(struct uart_port *port)
1037{
1038 return port->type == SIRFSOC_PORT_TYPE ? SIRFUART_PORT_NAME : NULL;
1039}
1040
1041static 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
1051static void sirfsoc_uart_release_port(struct uart_port *port)
1052{
1053 release_mem_region(port->mapbase, SIRFUART_MAP_SIZE);
1054}
1055
1056static 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
1064static 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
1084static int __init
1085sirfsoc_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
1116static 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
1127static 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
1136static 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
1146static int __init sirfsoc_uart_console_init(void)
1147{
1148 register_console(&sirfsoc_uart_console);
1149 return 0;
1150}
1151console_initcall(sirfsoc_uart_console_init);
1152#endif
1153
1154static 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
1168static enum hrtimer_restart
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 }
1251next_hrt:
1252 hrtimer_forward_now(hrt, ns_to_ktime(sirfport->rx_period_time));
1253 return HRTIMER_RESTART;
1254}
1255
1256static 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};
1263MODULE_DEVICE_TABLE(of, sirfsoc_uart_ids);
1264
1265static int sirfsoc_uart_probe(struct platform_device *pdev)
1266{
1267 struct device_node *np = pdev->dev.of_node;
1268 struct sirfsoc_uart_port *sirfport;
1269 struct uart_port *port;
1270 struct resource *res;
1271 int ret;
1272 struct dma_slave_config slv_cfg = {
1273 .src_maxburst = 1,
1274 };
1275 struct dma_slave_config tx_slv_cfg = {
1276 .dst_maxburst = 2,
1277 };
1278 const struct of_device_id *match;
1279
1280 match = of_match_node(sirfsoc_uart_ids, np);
1281 sirfport = devm_kzalloc(&pdev->dev, sizeof(*sirfport), GFP_KERNEL);
1282 if (!sirfport) {
1283 ret = -ENOMEM;
1284 goto err;
1285 }
1286 sirfport->port.line = of_alias_get_id(np, "serial");
1287 sirf_ports[sirfport->port.line] = sirfport;
1288 sirfport->port.iotype = UPIO_MEM;
1289 sirfport->port.flags = UPF_BOOT_AUTOCONF;
1290 port = &sirfport->port;
1291 port->dev = &pdev->dev;
1292 port->private_data = sirfport;
1293 sirfport->uart_reg = (struct sirfsoc_uart_register *)match->data;
1294
1295 sirfport->hw_flow_ctrl =
1296 of_property_read_bool(np, "uart-has-rtscts") ||
1297 of_property_read_bool(np, "sirf,uart-has-rtscts") /* deprecated */;
1298 if (of_device_is_compatible(np, "sirf,prima2-uart") ||
1299 of_device_is_compatible(np, "sirf,atlas7-uart"))
1300 sirfport->uart_reg->uart_type = SIRF_REAL_UART;
1301 if (of_device_is_compatible(np, "sirf,prima2-usp-uart") ||
1302 of_device_is_compatible(np, "sirf,atlas7-usp-uart")) {
1303 sirfport->uart_reg->uart_type = SIRF_USP_UART;
1304 if (!sirfport->hw_flow_ctrl)
1305 goto usp_no_flow_control;
1306 if (of_find_property(np, "cts-gpios", NULL))
1307 sirfport->cts_gpio =
1308 of_get_named_gpio(np, "cts-gpios", 0);
1309 else
1310 sirfport->cts_gpio = -1;
1311 if (of_find_property(np, "rts-gpios", NULL))
1312 sirfport->rts_gpio =
1313 of_get_named_gpio(np, "rts-gpios", 0);
1314 else
1315 sirfport->rts_gpio = -1;
1316
1317 if ((!gpio_is_valid(sirfport->cts_gpio) ||
1318 !gpio_is_valid(sirfport->rts_gpio))) {
1319 ret = -EINVAL;
1320 dev_err(&pdev->dev,
1321 "Usp flow control must have cts and rts gpio");
1322 goto err;
1323 }
1324 ret = devm_gpio_request(&pdev->dev, sirfport->cts_gpio,
1325 "usp-cts-gpio");
1326 if (ret) {
1327 dev_err(&pdev->dev, "Unable request cts gpio");
1328 goto err;
1329 }
1330 gpio_direction_input(sirfport->cts_gpio);
1331 ret = devm_gpio_request(&pdev->dev, sirfport->rts_gpio,
1332 "usp-rts-gpio");
1333 if (ret) {
1334 dev_err(&pdev->dev, "Unable request rts gpio");
1335 goto err;
1336 }
1337 gpio_direction_output(sirfport->rts_gpio, 1);
1338 }
1339usp_no_flow_control:
1340 if (of_device_is_compatible(np, "sirf,atlas7-uart") ||
1341 of_device_is_compatible(np, "sirf,atlas7-usp-uart"))
1342 sirfport->is_atlas7 = true;
1343
1344 if (of_property_read_u32(np, "fifosize", &port->fifosize)) {
1345 dev_err(&pdev->dev,
1346 "Unable to find fifosize in uart node.\n");
1347 ret = -EFAULT;
1348 goto err;
1349 }
1350
1351 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1352 if (res == NULL) {
1353 dev_err(&pdev->dev, "Insufficient resources.\n");
1354 ret = -EFAULT;
1355 goto err;
1356 }
1357 port->mapbase = res->start;
1358 port->membase = devm_ioremap(&pdev->dev,
1359 res->start, resource_size(res));
1360 if (!port->membase) {
1361 dev_err(&pdev->dev, "Cannot remap resource.\n");
1362 ret = -ENOMEM;
1363 goto err;
1364 }
1365 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1366 if (res == NULL) {
1367 dev_err(&pdev->dev, "Insufficient resources.\n");
1368 ret = -EFAULT;
1369 goto err;
1370 }
1371 port->irq = res->start;
1372
1373 sirfport->clk = devm_clk_get(&pdev->dev, NULL);
1374 if (IS_ERR(sirfport->clk)) {
1375 ret = PTR_ERR(sirfport->clk);
1376 goto err;
1377 }
1378 port->uartclk = clk_get_rate(sirfport->clk);
1379
1380 port->ops = &sirfsoc_uart_ops;
1381 spin_lock_init(&port->lock);
1382
1383 platform_set_drvdata(pdev, sirfport);
1384 ret = uart_add_one_port(&sirfsoc_uart_drv, port);
1385 if (ret != 0) {
1386 dev_err(&pdev->dev, "Cannot add UART port(%d).\n", pdev->id);
1387 goto err;
1388 }
1389
1390 sirfport->rx_dma_chan = dma_request_slave_channel(port->dev, "rx");
1391 sirfport->rx_dma_items.xmit.buf =
1392 dma_alloc_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
1393 &sirfport->rx_dma_items.dma_addr, GFP_KERNEL);
1394 if (!sirfport->rx_dma_items.xmit.buf) {
1395 dev_err(port->dev, "Uart alloc bufa failed\n");
1396 ret = -ENOMEM;
1397 goto alloc_coherent_err;
1398 }
1399 sirfport->rx_dma_items.xmit.head =
1400 sirfport->rx_dma_items.xmit.tail = 0;
1401 if (sirfport->rx_dma_chan)
1402 dmaengine_slave_config(sirfport->rx_dma_chan, &slv_cfg);
1403 sirfport->tx_dma_chan = dma_request_slave_channel(port->dev, "tx");
1404 if (sirfport->tx_dma_chan)
1405 dmaengine_slave_config(sirfport->tx_dma_chan, &tx_slv_cfg);
1406 if (sirfport->rx_dma_chan) {
1407 hrtimer_init(&sirfport->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1408 sirfport->hrt.function = sirfsoc_uart_rx_dma_hrtimer_callback;
1409 sirfport->is_hrt_enabled = false;
1410 }
1411
1412 return 0;
1413alloc_coherent_err:
1414 dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
1415 sirfport->rx_dma_items.xmit.buf,
1416 sirfport->rx_dma_items.dma_addr);
1417 dma_release_channel(sirfport->rx_dma_chan);
1418err:
1419 return ret;
1420}
1421
1422static int sirfsoc_uart_remove(struct platform_device *pdev)
1423{
1424 struct sirfsoc_uart_port *sirfport = platform_get_drvdata(pdev);
1425 struct uart_port *port = &sirfport->port;
1426 uart_remove_one_port(&sirfsoc_uart_drv, port);
1427 if (sirfport->rx_dma_chan) {
1428 dmaengine_terminate_all(sirfport->rx_dma_chan);
1429 dma_release_channel(sirfport->rx_dma_chan);
1430 dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
1431 sirfport->rx_dma_items.xmit.buf,
1432 sirfport->rx_dma_items.dma_addr);
1433 }
1434 if (sirfport->tx_dma_chan) {
1435 dmaengine_terminate_all(sirfport->tx_dma_chan);
1436 dma_release_channel(sirfport->tx_dma_chan);
1437 }
1438 return 0;
1439}
1440
1441#ifdef CONFIG_PM_SLEEP
1442static int
1443sirfsoc_uart_suspend(struct device *pdev)
1444{
1445 struct sirfsoc_uart_port *sirfport = dev_get_drvdata(pdev);
1446 struct uart_port *port = &sirfport->port;
1447 uart_suspend_port(&sirfsoc_uart_drv, port);
1448 return 0;
1449}
1450
1451static int sirfsoc_uart_resume(struct device *pdev)
1452{
1453 struct sirfsoc_uart_port *sirfport = dev_get_drvdata(pdev);
1454 struct uart_port *port = &sirfport->port;
1455 uart_resume_port(&sirfsoc_uart_drv, port);
1456 return 0;
1457}
1458#endif
1459
1460static const struct dev_pm_ops sirfsoc_uart_pm_ops = {
1461 SET_SYSTEM_SLEEP_PM_OPS(sirfsoc_uart_suspend, sirfsoc_uart_resume)
1462};
1463
1464static struct platform_driver sirfsoc_uart_driver = {
1465 .probe = sirfsoc_uart_probe,
1466 .remove = sirfsoc_uart_remove,
1467 .driver = {
1468 .name = SIRFUART_PORT_NAME,
1469 .of_match_table = sirfsoc_uart_ids,
1470 .pm = &sirfsoc_uart_pm_ops,
1471 },
1472};
1473
1474static int __init sirfsoc_uart_init(void)
1475{
1476 int ret = 0;
1477
1478 ret = uart_register_driver(&sirfsoc_uart_drv);
1479 if (ret)
1480 goto out;
1481
1482 ret = platform_driver_register(&sirfsoc_uart_driver);
1483 if (ret)
1484 uart_unregister_driver(&sirfsoc_uart_drv);
1485out:
1486 return ret;
1487}
1488module_init(sirfsoc_uart_init);
1489
1490static void __exit sirfsoc_uart_exit(void)
1491{
1492 platform_driver_unregister(&sirfsoc_uart_driver);
1493 uart_unregister_driver(&sirfsoc_uart_drv);
1494}
1495module_exit(sirfsoc_uart_exit);
1496
1497MODULE_LICENSE("GPL v2");
1498MODULE_AUTHOR("Bin Shi <Bin.Shi@csr.com>, Rong Wang<Rong.Wang@csr.com>");
1499MODULE_DESCRIPTION("CSR SiRFprimaII Uart Driver");