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1da177e4 | 1 | /* |
1da177e4 LT |
2 | * Driver for AMBA serial ports |
3 | * | |
4 | * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. | |
5 | * | |
6 | * Copyright 1999 ARM Limited | |
7 | * Copyright (C) 2000 Deep Blue Solutions Ltd. | |
68b65f73 | 8 | * Copyright (C) 2010 ST-Ericsson SA |
1da177e4 LT |
9 | * |
10 | * This program is free software; you can redistribute it and/or modify | |
11 | * it under the terms of the GNU General Public License as published by | |
12 | * the Free Software Foundation; either version 2 of the License, or | |
13 | * (at your option) any later version. | |
14 | * | |
15 | * This program is distributed in the hope that it will be useful, | |
16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
18 | * GNU General Public License for more details. | |
19 | * | |
20 | * You should have received a copy of the GNU General Public License | |
21 | * along with this program; if not, write to the Free Software | |
22 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
23 | * | |
1da177e4 LT |
24 | * This is a generic driver for ARM AMBA-type serial ports. They |
25 | * have a lot of 16550-like features, but are not register compatible. | |
26 | * Note that although they do have CTS, DCD and DSR inputs, they do | |
27 | * not have an RI input, nor do they have DTR or RTS outputs. If | |
28 | * required, these have to be supplied via some other means (eg, GPIO) | |
29 | * and hooked into this driver. | |
30 | */ | |
1da177e4 LT |
31 | |
32 | #if defined(CONFIG_SERIAL_AMBA_PL011_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) | |
33 | #define SUPPORT_SYSRQ | |
34 | #endif | |
35 | ||
36 | #include <linux/module.h> | |
37 | #include <linux/ioport.h> | |
38 | #include <linux/init.h> | |
39 | #include <linux/console.h> | |
40 | #include <linux/sysrq.h> | |
41 | #include <linux/device.h> | |
42 | #include <linux/tty.h> | |
43 | #include <linux/tty_flip.h> | |
44 | #include <linux/serial_core.h> | |
45 | #include <linux/serial.h> | |
a62c80e5 RK |
46 | #include <linux/amba/bus.h> |
47 | #include <linux/amba/serial.h> | |
f8ce2547 | 48 | #include <linux/clk.h> |
5a0e3ad6 | 49 | #include <linux/slab.h> |
68b65f73 RK |
50 | #include <linux/dmaengine.h> |
51 | #include <linux/dma-mapping.h> | |
52 | #include <linux/scatterlist.h> | |
c16d51a3 | 53 | #include <linux/delay.h> |
258aea76 | 54 | #include <linux/types.h> |
32614aad ML |
55 | #include <linux/of.h> |
56 | #include <linux/of_device.h> | |
258e0551 | 57 | #include <linux/pinctrl/consumer.h> |
cb70706c | 58 | #include <linux/sizes.h> |
de609582 | 59 | #include <linux/io.h> |
1da177e4 LT |
60 | |
61 | #define UART_NR 14 | |
62 | ||
63 | #define SERIAL_AMBA_MAJOR 204 | |
64 | #define SERIAL_AMBA_MINOR 64 | |
65 | #define SERIAL_AMBA_NR UART_NR | |
66 | ||
67 | #define AMBA_ISR_PASS_LIMIT 256 | |
68 | ||
b63d4f0f RK |
69 | #define UART_DR_ERROR (UART011_DR_OE|UART011_DR_BE|UART011_DR_PE|UART011_DR_FE) |
70 | #define UART_DUMMY_DR_RX (1 << 16) | |
1da177e4 | 71 | |
5926a295 AR |
72 | /* There is by now at least one vendor with differing details, so handle it */ |
73 | struct vendor_data { | |
74 | unsigned int ifls; | |
75 | unsigned int fifosize; | |
ec489aa8 LW |
76 | unsigned int lcrh_tx; |
77 | unsigned int lcrh_rx; | |
ac3e3fb4 | 78 | bool oversampling; |
38d62436 | 79 | bool dma_threshold; |
4fd0690b | 80 | bool cts_event_workaround; |
5926a295 AR |
81 | }; |
82 | ||
83 | static struct vendor_data vendor_arm = { | |
84 | .ifls = UART011_IFLS_RX4_8|UART011_IFLS_TX4_8, | |
85 | .fifosize = 16, | |
ec489aa8 LW |
86 | .lcrh_tx = UART011_LCRH, |
87 | .lcrh_rx = UART011_LCRH, | |
ac3e3fb4 | 88 | .oversampling = false, |
38d62436 | 89 | .dma_threshold = false, |
4fd0690b | 90 | .cts_event_workaround = false, |
5926a295 AR |
91 | }; |
92 | ||
93 | static struct vendor_data vendor_st = { | |
94 | .ifls = UART011_IFLS_RX_HALF|UART011_IFLS_TX_HALF, | |
95 | .fifosize = 64, | |
ec489aa8 LW |
96 | .lcrh_tx = ST_UART011_LCRH_TX, |
97 | .lcrh_rx = ST_UART011_LCRH_RX, | |
ac3e3fb4 | 98 | .oversampling = true, |
38d62436 | 99 | .dma_threshold = true, |
4fd0690b | 100 | .cts_event_workaround = true, |
1da177e4 LT |
101 | }; |
102 | ||
c16d51a3 SKS |
103 | static struct uart_amba_port *amba_ports[UART_NR]; |
104 | ||
68b65f73 | 105 | /* Deals with DMA transactions */ |
ead76f32 LW |
106 | |
107 | struct pl011_sgbuf { | |
108 | struct scatterlist sg; | |
109 | char *buf; | |
110 | }; | |
111 | ||
112 | struct pl011_dmarx_data { | |
113 | struct dma_chan *chan; | |
114 | struct completion complete; | |
115 | bool use_buf_b; | |
116 | struct pl011_sgbuf sgbuf_a; | |
117 | struct pl011_sgbuf sgbuf_b; | |
118 | dma_cookie_t cookie; | |
119 | bool running; | |
120 | }; | |
121 | ||
68b65f73 RK |
122 | struct pl011_dmatx_data { |
123 | struct dma_chan *chan; | |
124 | struct scatterlist sg; | |
125 | char *buf; | |
126 | bool queued; | |
127 | }; | |
128 | ||
c19f12b5 RK |
129 | /* |
130 | * We wrap our port structure around the generic uart_port. | |
131 | */ | |
132 | struct uart_amba_port { | |
133 | struct uart_port port; | |
134 | struct clk *clk; | |
78d80c5a LW |
135 | /* Two optional pin states - default & sleep */ |
136 | struct pinctrl *pinctrl; | |
137 | struct pinctrl_state *pins_default; | |
138 | struct pinctrl_state *pins_sleep; | |
c19f12b5 | 139 | const struct vendor_data *vendor; |
68b65f73 | 140 | unsigned int dmacr; /* dma control reg */ |
c19f12b5 RK |
141 | unsigned int im; /* interrupt mask */ |
142 | unsigned int old_status; | |
ffca2b11 | 143 | unsigned int fifosize; /* vendor-specific */ |
c19f12b5 RK |
144 | unsigned int lcrh_tx; /* vendor-specific */ |
145 | unsigned int lcrh_rx; /* vendor-specific */ | |
d8d8ffa4 | 146 | unsigned int old_cr; /* state during shutdown */ |
c19f12b5 RK |
147 | bool autorts; |
148 | char type[12]; | |
68b65f73 RK |
149 | #ifdef CONFIG_DMA_ENGINE |
150 | /* DMA stuff */ | |
ead76f32 LW |
151 | bool using_tx_dma; |
152 | bool using_rx_dma; | |
153 | struct pl011_dmarx_data dmarx; | |
68b65f73 RK |
154 | struct pl011_dmatx_data dmatx; |
155 | #endif | |
156 | }; | |
157 | ||
29772c4e LW |
158 | /* |
159 | * Reads up to 256 characters from the FIFO or until it's empty and | |
160 | * inserts them into the TTY layer. Returns the number of characters | |
161 | * read from the FIFO. | |
162 | */ | |
163 | static int pl011_fifo_to_tty(struct uart_amba_port *uap) | |
164 | { | |
165 | u16 status, ch; | |
166 | unsigned int flag, max_count = 256; | |
167 | int fifotaken = 0; | |
168 | ||
169 | while (max_count--) { | |
170 | status = readw(uap->port.membase + UART01x_FR); | |
171 | if (status & UART01x_FR_RXFE) | |
172 | break; | |
173 | ||
174 | /* Take chars from the FIFO and update status */ | |
175 | ch = readw(uap->port.membase + UART01x_DR) | | |
176 | UART_DUMMY_DR_RX; | |
177 | flag = TTY_NORMAL; | |
178 | uap->port.icount.rx++; | |
179 | fifotaken++; | |
180 | ||
181 | if (unlikely(ch & UART_DR_ERROR)) { | |
182 | if (ch & UART011_DR_BE) { | |
183 | ch &= ~(UART011_DR_FE | UART011_DR_PE); | |
184 | uap->port.icount.brk++; | |
185 | if (uart_handle_break(&uap->port)) | |
186 | continue; | |
187 | } else if (ch & UART011_DR_PE) | |
188 | uap->port.icount.parity++; | |
189 | else if (ch & UART011_DR_FE) | |
190 | uap->port.icount.frame++; | |
191 | if (ch & UART011_DR_OE) | |
192 | uap->port.icount.overrun++; | |
193 | ||
194 | ch &= uap->port.read_status_mask; | |
195 | ||
196 | if (ch & UART011_DR_BE) | |
197 | flag = TTY_BREAK; | |
198 | else if (ch & UART011_DR_PE) | |
199 | flag = TTY_PARITY; | |
200 | else if (ch & UART011_DR_FE) | |
201 | flag = TTY_FRAME; | |
202 | } | |
203 | ||
204 | if (uart_handle_sysrq_char(&uap->port, ch & 255)) | |
205 | continue; | |
206 | ||
207 | uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag); | |
208 | } | |
209 | ||
210 | return fifotaken; | |
211 | } | |
212 | ||
213 | ||
68b65f73 RK |
214 | /* |
215 | * All the DMA operation mode stuff goes inside this ifdef. | |
216 | * This assumes that you have a generic DMA device interface, | |
217 | * no custom DMA interfaces are supported. | |
218 | */ | |
219 | #ifdef CONFIG_DMA_ENGINE | |
220 | ||
221 | #define PL011_DMA_BUFFER_SIZE PAGE_SIZE | |
222 | ||
ead76f32 LW |
223 | static int pl011_sgbuf_init(struct dma_chan *chan, struct pl011_sgbuf *sg, |
224 | enum dma_data_direction dir) | |
225 | { | |
226 | sg->buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL); | |
227 | if (!sg->buf) | |
228 | return -ENOMEM; | |
229 | ||
230 | sg_init_one(&sg->sg, sg->buf, PL011_DMA_BUFFER_SIZE); | |
231 | ||
232 | if (dma_map_sg(chan->device->dev, &sg->sg, 1, dir) != 1) { | |
233 | kfree(sg->buf); | |
234 | return -EINVAL; | |
235 | } | |
236 | return 0; | |
237 | } | |
238 | ||
239 | static void pl011_sgbuf_free(struct dma_chan *chan, struct pl011_sgbuf *sg, | |
240 | enum dma_data_direction dir) | |
241 | { | |
242 | if (sg->buf) { | |
243 | dma_unmap_sg(chan->device->dev, &sg->sg, 1, dir); | |
244 | kfree(sg->buf); | |
245 | } | |
246 | } | |
247 | ||
68b65f73 RK |
248 | static void pl011_dma_probe_initcall(struct uart_amba_port *uap) |
249 | { | |
250 | /* DMA is the sole user of the platform data right now */ | |
251 | struct amba_pl011_data *plat = uap->port.dev->platform_data; | |
252 | struct dma_slave_config tx_conf = { | |
253 | .dst_addr = uap->port.mapbase + UART01x_DR, | |
254 | .dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, | |
a485df4b | 255 | .direction = DMA_MEM_TO_DEV, |
68b65f73 | 256 | .dst_maxburst = uap->fifosize >> 1, |
258aea76 | 257 | .device_fc = false, |
68b65f73 RK |
258 | }; |
259 | struct dma_chan *chan; | |
260 | dma_cap_mask_t mask; | |
261 | ||
262 | /* We need platform data */ | |
263 | if (!plat || !plat->dma_filter) { | |
264 | dev_info(uap->port.dev, "no DMA platform data\n"); | |
265 | return; | |
266 | } | |
267 | ||
ead76f32 | 268 | /* Try to acquire a generic DMA engine slave TX channel */ |
68b65f73 RK |
269 | dma_cap_zero(mask); |
270 | dma_cap_set(DMA_SLAVE, mask); | |
271 | ||
272 | chan = dma_request_channel(mask, plat->dma_filter, plat->dma_tx_param); | |
273 | if (!chan) { | |
274 | dev_err(uap->port.dev, "no TX DMA channel!\n"); | |
275 | return; | |
276 | } | |
277 | ||
278 | dmaengine_slave_config(chan, &tx_conf); | |
279 | uap->dmatx.chan = chan; | |
280 | ||
281 | dev_info(uap->port.dev, "DMA channel TX %s\n", | |
282 | dma_chan_name(uap->dmatx.chan)); | |
ead76f32 LW |
283 | |
284 | /* Optionally make use of an RX channel as well */ | |
285 | if (plat->dma_rx_param) { | |
286 | struct dma_slave_config rx_conf = { | |
287 | .src_addr = uap->port.mapbase + UART01x_DR, | |
288 | .src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, | |
a485df4b | 289 | .direction = DMA_DEV_TO_MEM, |
ead76f32 | 290 | .src_maxburst = uap->fifosize >> 1, |
258aea76 | 291 | .device_fc = false, |
ead76f32 LW |
292 | }; |
293 | ||
294 | chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param); | |
295 | if (!chan) { | |
296 | dev_err(uap->port.dev, "no RX DMA channel!\n"); | |
297 | return; | |
298 | } | |
299 | ||
300 | dmaengine_slave_config(chan, &rx_conf); | |
301 | uap->dmarx.chan = chan; | |
302 | ||
303 | dev_info(uap->port.dev, "DMA channel RX %s\n", | |
304 | dma_chan_name(uap->dmarx.chan)); | |
305 | } | |
68b65f73 RK |
306 | } |
307 | ||
308 | #ifndef MODULE | |
309 | /* | |
310 | * Stack up the UARTs and let the above initcall be done at device | |
311 | * initcall time, because the serial driver is called as an arch | |
312 | * initcall, and at this time the DMA subsystem is not yet registered. | |
313 | * At this point the driver will switch over to using DMA where desired. | |
314 | */ | |
315 | struct dma_uap { | |
316 | struct list_head node; | |
317 | struct uart_amba_port *uap; | |
c19f12b5 RK |
318 | }; |
319 | ||
68b65f73 RK |
320 | static LIST_HEAD(pl011_dma_uarts); |
321 | ||
322 | static int __init pl011_dma_initcall(void) | |
323 | { | |
324 | struct list_head *node, *tmp; | |
325 | ||
326 | list_for_each_safe(node, tmp, &pl011_dma_uarts) { | |
327 | struct dma_uap *dmau = list_entry(node, struct dma_uap, node); | |
328 | pl011_dma_probe_initcall(dmau->uap); | |
329 | list_del(node); | |
330 | kfree(dmau); | |
331 | } | |
332 | return 0; | |
333 | } | |
334 | ||
335 | device_initcall(pl011_dma_initcall); | |
336 | ||
337 | static void pl011_dma_probe(struct uart_amba_port *uap) | |
338 | { | |
339 | struct dma_uap *dmau = kzalloc(sizeof(struct dma_uap), GFP_KERNEL); | |
340 | if (dmau) { | |
341 | dmau->uap = uap; | |
342 | list_add_tail(&dmau->node, &pl011_dma_uarts); | |
343 | } | |
344 | } | |
345 | #else | |
346 | static void pl011_dma_probe(struct uart_amba_port *uap) | |
347 | { | |
348 | pl011_dma_probe_initcall(uap); | |
349 | } | |
350 | #endif | |
351 | ||
352 | static void pl011_dma_remove(struct uart_amba_port *uap) | |
353 | { | |
354 | /* TODO: remove the initcall if it has not yet executed */ | |
355 | if (uap->dmatx.chan) | |
356 | dma_release_channel(uap->dmatx.chan); | |
ead76f32 LW |
357 | if (uap->dmarx.chan) |
358 | dma_release_channel(uap->dmarx.chan); | |
68b65f73 RK |
359 | } |
360 | ||
68b65f73 RK |
361 | /* Forward declare this for the refill routine */ |
362 | static int pl011_dma_tx_refill(struct uart_amba_port *uap); | |
363 | ||
364 | /* | |
365 | * The current DMA TX buffer has been sent. | |
366 | * Try to queue up another DMA buffer. | |
367 | */ | |
368 | static void pl011_dma_tx_callback(void *data) | |
369 | { | |
370 | struct uart_amba_port *uap = data; | |
371 | struct pl011_dmatx_data *dmatx = &uap->dmatx; | |
372 | unsigned long flags; | |
373 | u16 dmacr; | |
374 | ||
375 | spin_lock_irqsave(&uap->port.lock, flags); | |
376 | if (uap->dmatx.queued) | |
377 | dma_unmap_sg(dmatx->chan->device->dev, &dmatx->sg, 1, | |
378 | DMA_TO_DEVICE); | |
379 | ||
380 | dmacr = uap->dmacr; | |
381 | uap->dmacr = dmacr & ~UART011_TXDMAE; | |
382 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
383 | ||
384 | /* | |
385 | * If TX DMA was disabled, it means that we've stopped the DMA for | |
386 | * some reason (eg, XOFF received, or we want to send an X-char.) | |
387 | * | |
388 | * Note: we need to be careful here of a potential race between DMA | |
389 | * and the rest of the driver - if the driver disables TX DMA while | |
390 | * a TX buffer completing, we must update the tx queued status to | |
391 | * get further refills (hence we check dmacr). | |
392 | */ | |
393 | if (!(dmacr & UART011_TXDMAE) || uart_tx_stopped(&uap->port) || | |
394 | uart_circ_empty(&uap->port.state->xmit)) { | |
395 | uap->dmatx.queued = false; | |
396 | spin_unlock_irqrestore(&uap->port.lock, flags); | |
397 | return; | |
398 | } | |
399 | ||
400 | if (pl011_dma_tx_refill(uap) <= 0) { | |
401 | /* | |
402 | * We didn't queue a DMA buffer for some reason, but we | |
403 | * have data pending to be sent. Re-enable the TX IRQ. | |
404 | */ | |
405 | uap->im |= UART011_TXIM; | |
406 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
407 | } | |
408 | spin_unlock_irqrestore(&uap->port.lock, flags); | |
409 | } | |
410 | ||
411 | /* | |
412 | * Try to refill the TX DMA buffer. | |
413 | * Locking: called with port lock held and IRQs disabled. | |
414 | * Returns: | |
415 | * 1 if we queued up a TX DMA buffer. | |
416 | * 0 if we didn't want to handle this by DMA | |
417 | * <0 on error | |
418 | */ | |
419 | static int pl011_dma_tx_refill(struct uart_amba_port *uap) | |
420 | { | |
421 | struct pl011_dmatx_data *dmatx = &uap->dmatx; | |
422 | struct dma_chan *chan = dmatx->chan; | |
423 | struct dma_device *dma_dev = chan->device; | |
424 | struct dma_async_tx_descriptor *desc; | |
425 | struct circ_buf *xmit = &uap->port.state->xmit; | |
426 | unsigned int count; | |
427 | ||
428 | /* | |
429 | * Try to avoid the overhead involved in using DMA if the | |
430 | * transaction fits in the first half of the FIFO, by using | |
431 | * the standard interrupt handling. This ensures that we | |
432 | * issue a uart_write_wakeup() at the appropriate time. | |
433 | */ | |
434 | count = uart_circ_chars_pending(xmit); | |
435 | if (count < (uap->fifosize >> 1)) { | |
436 | uap->dmatx.queued = false; | |
437 | return 0; | |
438 | } | |
439 | ||
440 | /* | |
441 | * Bodge: don't send the last character by DMA, as this | |
442 | * will prevent XON from notifying us to restart DMA. | |
443 | */ | |
444 | count -= 1; | |
445 | ||
446 | /* Else proceed to copy the TX chars to the DMA buffer and fire DMA */ | |
447 | if (count > PL011_DMA_BUFFER_SIZE) | |
448 | count = PL011_DMA_BUFFER_SIZE; | |
449 | ||
450 | if (xmit->tail < xmit->head) | |
451 | memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], count); | |
452 | else { | |
453 | size_t first = UART_XMIT_SIZE - xmit->tail; | |
454 | size_t second = xmit->head; | |
455 | ||
456 | memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], first); | |
457 | if (second) | |
458 | memcpy(&dmatx->buf[first], &xmit->buf[0], second); | |
459 | } | |
460 | ||
461 | dmatx->sg.length = count; | |
462 | ||
463 | if (dma_map_sg(dma_dev->dev, &dmatx->sg, 1, DMA_TO_DEVICE) != 1) { | |
464 | uap->dmatx.queued = false; | |
465 | dev_dbg(uap->port.dev, "unable to map TX DMA\n"); | |
466 | return -EBUSY; | |
467 | } | |
468 | ||
16052827 | 469 | desc = dmaengine_prep_slave_sg(chan, &dmatx->sg, 1, DMA_MEM_TO_DEV, |
68b65f73 RK |
470 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
471 | if (!desc) { | |
472 | dma_unmap_sg(dma_dev->dev, &dmatx->sg, 1, DMA_TO_DEVICE); | |
473 | uap->dmatx.queued = false; | |
474 | /* | |
475 | * If DMA cannot be used right now, we complete this | |
476 | * transaction via IRQ and let the TTY layer retry. | |
477 | */ | |
478 | dev_dbg(uap->port.dev, "TX DMA busy\n"); | |
479 | return -EBUSY; | |
480 | } | |
481 | ||
482 | /* Some data to go along to the callback */ | |
483 | desc->callback = pl011_dma_tx_callback; | |
484 | desc->callback_param = uap; | |
485 | ||
486 | /* All errors should happen at prepare time */ | |
487 | dmaengine_submit(desc); | |
488 | ||
489 | /* Fire the DMA transaction */ | |
490 | dma_dev->device_issue_pending(chan); | |
491 | ||
492 | uap->dmacr |= UART011_TXDMAE; | |
493 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
494 | uap->dmatx.queued = true; | |
495 | ||
496 | /* | |
497 | * Now we know that DMA will fire, so advance the ring buffer | |
498 | * with the stuff we just dispatched. | |
499 | */ | |
500 | xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1); | |
501 | uap->port.icount.tx += count; | |
502 | ||
503 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) | |
504 | uart_write_wakeup(&uap->port); | |
505 | ||
506 | return 1; | |
507 | } | |
508 | ||
509 | /* | |
510 | * We received a transmit interrupt without a pending X-char but with | |
511 | * pending characters. | |
512 | * Locking: called with port lock held and IRQs disabled. | |
513 | * Returns: | |
514 | * false if we want to use PIO to transmit | |
515 | * true if we queued a DMA buffer | |
516 | */ | |
517 | static bool pl011_dma_tx_irq(struct uart_amba_port *uap) | |
518 | { | |
ead76f32 | 519 | if (!uap->using_tx_dma) |
68b65f73 RK |
520 | return false; |
521 | ||
522 | /* | |
523 | * If we already have a TX buffer queued, but received a | |
524 | * TX interrupt, it will be because we've just sent an X-char. | |
525 | * Ensure the TX DMA is enabled and the TX IRQ is disabled. | |
526 | */ | |
527 | if (uap->dmatx.queued) { | |
528 | uap->dmacr |= UART011_TXDMAE; | |
529 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
530 | uap->im &= ~UART011_TXIM; | |
531 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
532 | return true; | |
533 | } | |
534 | ||
535 | /* | |
536 | * We don't have a TX buffer queued, so try to queue one. | |
25985edc | 537 | * If we successfully queued a buffer, mask the TX IRQ. |
68b65f73 RK |
538 | */ |
539 | if (pl011_dma_tx_refill(uap) > 0) { | |
540 | uap->im &= ~UART011_TXIM; | |
541 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
542 | return true; | |
543 | } | |
544 | return false; | |
545 | } | |
546 | ||
547 | /* | |
548 | * Stop the DMA transmit (eg, due to received XOFF). | |
549 | * Locking: called with port lock held and IRQs disabled. | |
550 | */ | |
551 | static inline void pl011_dma_tx_stop(struct uart_amba_port *uap) | |
552 | { | |
553 | if (uap->dmatx.queued) { | |
554 | uap->dmacr &= ~UART011_TXDMAE; | |
555 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
556 | } | |
557 | } | |
558 | ||
559 | /* | |
560 | * Try to start a DMA transmit, or in the case of an XON/OFF | |
561 | * character queued for send, try to get that character out ASAP. | |
562 | * Locking: called with port lock held and IRQs disabled. | |
563 | * Returns: | |
564 | * false if we want the TX IRQ to be enabled | |
565 | * true if we have a buffer queued | |
566 | */ | |
567 | static inline bool pl011_dma_tx_start(struct uart_amba_port *uap) | |
568 | { | |
569 | u16 dmacr; | |
570 | ||
ead76f32 | 571 | if (!uap->using_tx_dma) |
68b65f73 RK |
572 | return false; |
573 | ||
574 | if (!uap->port.x_char) { | |
575 | /* no X-char, try to push chars out in DMA mode */ | |
576 | bool ret = true; | |
577 | ||
578 | if (!uap->dmatx.queued) { | |
579 | if (pl011_dma_tx_refill(uap) > 0) { | |
580 | uap->im &= ~UART011_TXIM; | |
581 | ret = true; | |
582 | } else { | |
583 | uap->im |= UART011_TXIM; | |
584 | ret = false; | |
585 | } | |
586 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
587 | } else if (!(uap->dmacr & UART011_TXDMAE)) { | |
588 | uap->dmacr |= UART011_TXDMAE; | |
589 | writew(uap->dmacr, | |
590 | uap->port.membase + UART011_DMACR); | |
591 | } | |
592 | return ret; | |
593 | } | |
594 | ||
595 | /* | |
596 | * We have an X-char to send. Disable DMA to prevent it loading | |
597 | * the TX fifo, and then see if we can stuff it into the FIFO. | |
598 | */ | |
599 | dmacr = uap->dmacr; | |
600 | uap->dmacr &= ~UART011_TXDMAE; | |
601 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
602 | ||
603 | if (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF) { | |
604 | /* | |
605 | * No space in the FIFO, so enable the transmit interrupt | |
606 | * so we know when there is space. Note that once we've | |
607 | * loaded the character, we should just re-enable DMA. | |
608 | */ | |
609 | return false; | |
610 | } | |
611 | ||
612 | writew(uap->port.x_char, uap->port.membase + UART01x_DR); | |
613 | uap->port.icount.tx++; | |
614 | uap->port.x_char = 0; | |
615 | ||
616 | /* Success - restore the DMA state */ | |
617 | uap->dmacr = dmacr; | |
618 | writew(dmacr, uap->port.membase + UART011_DMACR); | |
619 | ||
620 | return true; | |
621 | } | |
622 | ||
623 | /* | |
624 | * Flush the transmit buffer. | |
625 | * Locking: called with port lock held and IRQs disabled. | |
626 | */ | |
627 | static void pl011_dma_flush_buffer(struct uart_port *port) | |
628 | { | |
629 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
630 | ||
ead76f32 | 631 | if (!uap->using_tx_dma) |
68b65f73 RK |
632 | return; |
633 | ||
634 | /* Avoid deadlock with the DMA engine callback */ | |
635 | spin_unlock(&uap->port.lock); | |
636 | dmaengine_terminate_all(uap->dmatx.chan); | |
637 | spin_lock(&uap->port.lock); | |
638 | if (uap->dmatx.queued) { | |
639 | dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1, | |
640 | DMA_TO_DEVICE); | |
641 | uap->dmatx.queued = false; | |
642 | uap->dmacr &= ~UART011_TXDMAE; | |
643 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
644 | } | |
645 | } | |
646 | ||
ead76f32 LW |
647 | static void pl011_dma_rx_callback(void *data); |
648 | ||
649 | static int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap) | |
650 | { | |
651 | struct dma_chan *rxchan = uap->dmarx.chan; | |
ead76f32 LW |
652 | struct pl011_dmarx_data *dmarx = &uap->dmarx; |
653 | struct dma_async_tx_descriptor *desc; | |
654 | struct pl011_sgbuf *sgbuf; | |
655 | ||
656 | if (!rxchan) | |
657 | return -EIO; | |
658 | ||
659 | /* Start the RX DMA job */ | |
660 | sgbuf = uap->dmarx.use_buf_b ? | |
661 | &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a; | |
16052827 | 662 | desc = dmaengine_prep_slave_sg(rxchan, &sgbuf->sg, 1, |
a485df4b | 663 | DMA_DEV_TO_MEM, |
ead76f32 LW |
664 | DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
665 | /* | |
666 | * If the DMA engine is busy and cannot prepare a | |
667 | * channel, no big deal, the driver will fall back | |
668 | * to interrupt mode as a result of this error code. | |
669 | */ | |
670 | if (!desc) { | |
671 | uap->dmarx.running = false; | |
672 | dmaengine_terminate_all(rxchan); | |
673 | return -EBUSY; | |
674 | } | |
675 | ||
676 | /* Some data to go along to the callback */ | |
677 | desc->callback = pl011_dma_rx_callback; | |
678 | desc->callback_param = uap; | |
679 | dmarx->cookie = dmaengine_submit(desc); | |
680 | dma_async_issue_pending(rxchan); | |
681 | ||
682 | uap->dmacr |= UART011_RXDMAE; | |
683 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
684 | uap->dmarx.running = true; | |
685 | ||
686 | uap->im &= ~UART011_RXIM; | |
687 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
688 | ||
689 | return 0; | |
690 | } | |
691 | ||
692 | /* | |
693 | * This is called when either the DMA job is complete, or | |
694 | * the FIFO timeout interrupt occurred. This must be called | |
695 | * with the port spinlock uap->port.lock held. | |
696 | */ | |
697 | static void pl011_dma_rx_chars(struct uart_amba_port *uap, | |
698 | u32 pending, bool use_buf_b, | |
699 | bool readfifo) | |
700 | { | |
701 | struct tty_struct *tty = uap->port.state->port.tty; | |
702 | struct pl011_sgbuf *sgbuf = use_buf_b ? | |
703 | &uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a; | |
704 | struct device *dev = uap->dmarx.chan->device->dev; | |
ead76f32 LW |
705 | int dma_count = 0; |
706 | u32 fifotaken = 0; /* only used for vdbg() */ | |
707 | ||
708 | /* Pick everything from the DMA first */ | |
709 | if (pending) { | |
710 | /* Sync in buffer */ | |
711 | dma_sync_sg_for_cpu(dev, &sgbuf->sg, 1, DMA_FROM_DEVICE); | |
712 | ||
713 | /* | |
714 | * First take all chars in the DMA pipe, then look in the FIFO. | |
715 | * Note that tty_insert_flip_buf() tries to take as many chars | |
716 | * as it can. | |
717 | */ | |
718 | dma_count = tty_insert_flip_string(uap->port.state->port.tty, | |
719 | sgbuf->buf, pending); | |
720 | ||
721 | /* Return buffer to device */ | |
722 | dma_sync_sg_for_device(dev, &sgbuf->sg, 1, DMA_FROM_DEVICE); | |
723 | ||
724 | uap->port.icount.rx += dma_count; | |
725 | if (dma_count < pending) | |
726 | dev_warn(uap->port.dev, | |
727 | "couldn't insert all characters (TTY is full?)\n"); | |
728 | } | |
729 | ||
730 | /* | |
731 | * Only continue with trying to read the FIFO if all DMA chars have | |
732 | * been taken first. | |
733 | */ | |
734 | if (dma_count == pending && readfifo) { | |
735 | /* Clear any error flags */ | |
736 | writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS, | |
737 | uap->port.membase + UART011_ICR); | |
738 | ||
739 | /* | |
740 | * If we read all the DMA'd characters, and we had an | |
29772c4e LW |
741 | * incomplete buffer, that could be due to an rx error, or |
742 | * maybe we just timed out. Read any pending chars and check | |
743 | * the error status. | |
744 | * | |
745 | * Error conditions will only occur in the FIFO, these will | |
746 | * trigger an immediate interrupt and stop the DMA job, so we | |
747 | * will always find the error in the FIFO, never in the DMA | |
748 | * buffer. | |
ead76f32 | 749 | */ |
29772c4e | 750 | fifotaken = pl011_fifo_to_tty(uap); |
ead76f32 LW |
751 | } |
752 | ||
753 | spin_unlock(&uap->port.lock); | |
754 | dev_vdbg(uap->port.dev, | |
755 | "Took %d chars from DMA buffer and %d chars from the FIFO\n", | |
756 | dma_count, fifotaken); | |
757 | tty_flip_buffer_push(tty); | |
758 | spin_lock(&uap->port.lock); | |
759 | } | |
760 | ||
761 | static void pl011_dma_rx_irq(struct uart_amba_port *uap) | |
762 | { | |
763 | struct pl011_dmarx_data *dmarx = &uap->dmarx; | |
764 | struct dma_chan *rxchan = dmarx->chan; | |
765 | struct pl011_sgbuf *sgbuf = dmarx->use_buf_b ? | |
766 | &dmarx->sgbuf_b : &dmarx->sgbuf_a; | |
767 | size_t pending; | |
768 | struct dma_tx_state state; | |
769 | enum dma_status dmastat; | |
770 | ||
771 | /* | |
772 | * Pause the transfer so we can trust the current counter, | |
773 | * do this before we pause the PL011 block, else we may | |
774 | * overflow the FIFO. | |
775 | */ | |
776 | if (dmaengine_pause(rxchan)) | |
777 | dev_err(uap->port.dev, "unable to pause DMA transfer\n"); | |
778 | dmastat = rxchan->device->device_tx_status(rxchan, | |
779 | dmarx->cookie, &state); | |
780 | if (dmastat != DMA_PAUSED) | |
781 | dev_err(uap->port.dev, "unable to pause DMA transfer\n"); | |
782 | ||
783 | /* Disable RX DMA - incoming data will wait in the FIFO */ | |
784 | uap->dmacr &= ~UART011_RXDMAE; | |
785 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
786 | uap->dmarx.running = false; | |
787 | ||
788 | pending = sgbuf->sg.length - state.residue; | |
789 | BUG_ON(pending > PL011_DMA_BUFFER_SIZE); | |
790 | /* Then we terminate the transfer - we now know our residue */ | |
791 | dmaengine_terminate_all(rxchan); | |
792 | ||
793 | /* | |
794 | * This will take the chars we have so far and insert | |
795 | * into the framework. | |
796 | */ | |
797 | pl011_dma_rx_chars(uap, pending, dmarx->use_buf_b, true); | |
798 | ||
799 | /* Switch buffer & re-trigger DMA job */ | |
800 | dmarx->use_buf_b = !dmarx->use_buf_b; | |
801 | if (pl011_dma_rx_trigger_dma(uap)) { | |
802 | dev_dbg(uap->port.dev, "could not retrigger RX DMA job " | |
803 | "fall back to interrupt mode\n"); | |
804 | uap->im |= UART011_RXIM; | |
805 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
806 | } | |
807 | } | |
808 | ||
809 | static void pl011_dma_rx_callback(void *data) | |
810 | { | |
811 | struct uart_amba_port *uap = data; | |
812 | struct pl011_dmarx_data *dmarx = &uap->dmarx; | |
6dc01aa6 | 813 | struct dma_chan *rxchan = dmarx->chan; |
ead76f32 | 814 | bool lastbuf = dmarx->use_buf_b; |
6dc01aa6 CM |
815 | struct pl011_sgbuf *sgbuf = dmarx->use_buf_b ? |
816 | &dmarx->sgbuf_b : &dmarx->sgbuf_a; | |
817 | size_t pending; | |
818 | struct dma_tx_state state; | |
ead76f32 LW |
819 | int ret; |
820 | ||
821 | /* | |
822 | * This completion interrupt occurs typically when the | |
823 | * RX buffer is totally stuffed but no timeout has yet | |
824 | * occurred. When that happens, we just want the RX | |
825 | * routine to flush out the secondary DMA buffer while | |
826 | * we immediately trigger the next DMA job. | |
827 | */ | |
828 | spin_lock_irq(&uap->port.lock); | |
6dc01aa6 CM |
829 | /* |
830 | * Rx data can be taken by the UART interrupts during | |
831 | * the DMA irq handler. So we check the residue here. | |
832 | */ | |
833 | rxchan->device->device_tx_status(rxchan, dmarx->cookie, &state); | |
834 | pending = sgbuf->sg.length - state.residue; | |
835 | BUG_ON(pending > PL011_DMA_BUFFER_SIZE); | |
836 | /* Then we terminate the transfer - we now know our residue */ | |
837 | dmaengine_terminate_all(rxchan); | |
838 | ||
ead76f32 LW |
839 | uap->dmarx.running = false; |
840 | dmarx->use_buf_b = !lastbuf; | |
841 | ret = pl011_dma_rx_trigger_dma(uap); | |
842 | ||
6dc01aa6 | 843 | pl011_dma_rx_chars(uap, pending, lastbuf, false); |
ead76f32 LW |
844 | spin_unlock_irq(&uap->port.lock); |
845 | /* | |
846 | * Do this check after we picked the DMA chars so we don't | |
847 | * get some IRQ immediately from RX. | |
848 | */ | |
849 | if (ret) { | |
850 | dev_dbg(uap->port.dev, "could not retrigger RX DMA job " | |
851 | "fall back to interrupt mode\n"); | |
852 | uap->im |= UART011_RXIM; | |
853 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
854 | } | |
855 | } | |
856 | ||
857 | /* | |
858 | * Stop accepting received characters, when we're shutting down or | |
859 | * suspending this port. | |
860 | * Locking: called with port lock held and IRQs disabled. | |
861 | */ | |
862 | static inline void pl011_dma_rx_stop(struct uart_amba_port *uap) | |
863 | { | |
864 | /* FIXME. Just disable the DMA enable */ | |
865 | uap->dmacr &= ~UART011_RXDMAE; | |
866 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
867 | } | |
68b65f73 RK |
868 | |
869 | static void pl011_dma_startup(struct uart_amba_port *uap) | |
870 | { | |
ead76f32 LW |
871 | int ret; |
872 | ||
68b65f73 RK |
873 | if (!uap->dmatx.chan) |
874 | return; | |
875 | ||
876 | uap->dmatx.buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL); | |
877 | if (!uap->dmatx.buf) { | |
878 | dev_err(uap->port.dev, "no memory for DMA TX buffer\n"); | |
879 | uap->port.fifosize = uap->fifosize; | |
880 | return; | |
881 | } | |
882 | ||
883 | sg_init_one(&uap->dmatx.sg, uap->dmatx.buf, PL011_DMA_BUFFER_SIZE); | |
884 | ||
885 | /* The DMA buffer is now the FIFO the TTY subsystem can use */ | |
886 | uap->port.fifosize = PL011_DMA_BUFFER_SIZE; | |
ead76f32 LW |
887 | uap->using_tx_dma = true; |
888 | ||
889 | if (!uap->dmarx.chan) | |
890 | goto skip_rx; | |
891 | ||
892 | /* Allocate and map DMA RX buffers */ | |
893 | ret = pl011_sgbuf_init(uap->dmarx.chan, &uap->dmarx.sgbuf_a, | |
894 | DMA_FROM_DEVICE); | |
895 | if (ret) { | |
896 | dev_err(uap->port.dev, "failed to init DMA %s: %d\n", | |
897 | "RX buffer A", ret); | |
898 | goto skip_rx; | |
899 | } | |
68b65f73 | 900 | |
ead76f32 LW |
901 | ret = pl011_sgbuf_init(uap->dmarx.chan, &uap->dmarx.sgbuf_b, |
902 | DMA_FROM_DEVICE); | |
903 | if (ret) { | |
904 | dev_err(uap->port.dev, "failed to init DMA %s: %d\n", | |
905 | "RX buffer B", ret); | |
906 | pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_a, | |
907 | DMA_FROM_DEVICE); | |
908 | goto skip_rx; | |
909 | } | |
910 | ||
911 | uap->using_rx_dma = true; | |
68b65f73 | 912 | |
ead76f32 | 913 | skip_rx: |
68b65f73 RK |
914 | /* Turn on DMA error (RX/TX will be enabled on demand) */ |
915 | uap->dmacr |= UART011_DMAONERR; | |
916 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
38d62436 RK |
917 | |
918 | /* | |
919 | * ST Micro variants has some specific dma burst threshold | |
920 | * compensation. Set this to 16 bytes, so burst will only | |
921 | * be issued above/below 16 bytes. | |
922 | */ | |
923 | if (uap->vendor->dma_threshold) | |
924 | writew(ST_UART011_DMAWM_RX_16 | ST_UART011_DMAWM_TX_16, | |
925 | uap->port.membase + ST_UART011_DMAWM); | |
ead76f32 LW |
926 | |
927 | if (uap->using_rx_dma) { | |
928 | if (pl011_dma_rx_trigger_dma(uap)) | |
929 | dev_dbg(uap->port.dev, "could not trigger initial " | |
930 | "RX DMA job, fall back to interrupt mode\n"); | |
931 | } | |
68b65f73 RK |
932 | } |
933 | ||
934 | static void pl011_dma_shutdown(struct uart_amba_port *uap) | |
935 | { | |
ead76f32 | 936 | if (!(uap->using_tx_dma || uap->using_rx_dma)) |
68b65f73 RK |
937 | return; |
938 | ||
939 | /* Disable RX and TX DMA */ | |
940 | while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY) | |
941 | barrier(); | |
942 | ||
943 | spin_lock_irq(&uap->port.lock); | |
944 | uap->dmacr &= ~(UART011_DMAONERR | UART011_RXDMAE | UART011_TXDMAE); | |
945 | writew(uap->dmacr, uap->port.membase + UART011_DMACR); | |
946 | spin_unlock_irq(&uap->port.lock); | |
947 | ||
ead76f32 LW |
948 | if (uap->using_tx_dma) { |
949 | /* In theory, this should already be done by pl011_dma_flush_buffer */ | |
950 | dmaengine_terminate_all(uap->dmatx.chan); | |
951 | if (uap->dmatx.queued) { | |
952 | dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1, | |
953 | DMA_TO_DEVICE); | |
954 | uap->dmatx.queued = false; | |
955 | } | |
956 | ||
957 | kfree(uap->dmatx.buf); | |
958 | uap->using_tx_dma = false; | |
68b65f73 RK |
959 | } |
960 | ||
ead76f32 LW |
961 | if (uap->using_rx_dma) { |
962 | dmaengine_terminate_all(uap->dmarx.chan); | |
963 | /* Clean up the RX DMA */ | |
964 | pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_a, DMA_FROM_DEVICE); | |
965 | pl011_sgbuf_free(uap->dmarx.chan, &uap->dmarx.sgbuf_b, DMA_FROM_DEVICE); | |
966 | uap->using_rx_dma = false; | |
967 | } | |
968 | } | |
68b65f73 | 969 | |
ead76f32 LW |
970 | static inline bool pl011_dma_rx_available(struct uart_amba_port *uap) |
971 | { | |
972 | return uap->using_rx_dma; | |
68b65f73 RK |
973 | } |
974 | ||
ead76f32 LW |
975 | static inline bool pl011_dma_rx_running(struct uart_amba_port *uap) |
976 | { | |
977 | return uap->using_rx_dma && uap->dmarx.running; | |
978 | } | |
979 | ||
980 | ||
68b65f73 RK |
981 | #else |
982 | /* Blank functions if the DMA engine is not available */ | |
983 | static inline void pl011_dma_probe(struct uart_amba_port *uap) | |
984 | { | |
985 | } | |
986 | ||
987 | static inline void pl011_dma_remove(struct uart_amba_port *uap) | |
988 | { | |
989 | } | |
990 | ||
991 | static inline void pl011_dma_startup(struct uart_amba_port *uap) | |
992 | { | |
993 | } | |
994 | ||
995 | static inline void pl011_dma_shutdown(struct uart_amba_port *uap) | |
996 | { | |
997 | } | |
998 | ||
999 | static inline bool pl011_dma_tx_irq(struct uart_amba_port *uap) | |
1000 | { | |
1001 | return false; | |
1002 | } | |
1003 | ||
1004 | static inline void pl011_dma_tx_stop(struct uart_amba_port *uap) | |
1005 | { | |
1006 | } | |
1007 | ||
1008 | static inline bool pl011_dma_tx_start(struct uart_amba_port *uap) | |
1009 | { | |
1010 | return false; | |
1011 | } | |
1012 | ||
ead76f32 LW |
1013 | static inline void pl011_dma_rx_irq(struct uart_amba_port *uap) |
1014 | { | |
1015 | } | |
1016 | ||
1017 | static inline void pl011_dma_rx_stop(struct uart_amba_port *uap) | |
1018 | { | |
1019 | } | |
1020 | ||
1021 | static inline int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap) | |
1022 | { | |
1023 | return -EIO; | |
1024 | } | |
1025 | ||
1026 | static inline bool pl011_dma_rx_available(struct uart_amba_port *uap) | |
1027 | { | |
1028 | return false; | |
1029 | } | |
1030 | ||
1031 | static inline bool pl011_dma_rx_running(struct uart_amba_port *uap) | |
1032 | { | |
1033 | return false; | |
1034 | } | |
1035 | ||
68b65f73 RK |
1036 | #define pl011_dma_flush_buffer NULL |
1037 | #endif | |
1038 | ||
b129a8cc | 1039 | static void pl011_stop_tx(struct uart_port *port) |
1da177e4 LT |
1040 | { |
1041 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1042 | ||
1043 | uap->im &= ~UART011_TXIM; | |
1044 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
68b65f73 | 1045 | pl011_dma_tx_stop(uap); |
1da177e4 LT |
1046 | } |
1047 | ||
b129a8cc | 1048 | static void pl011_start_tx(struct uart_port *port) |
1da177e4 LT |
1049 | { |
1050 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1051 | ||
68b65f73 RK |
1052 | if (!pl011_dma_tx_start(uap)) { |
1053 | uap->im |= UART011_TXIM; | |
1054 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
1055 | } | |
1da177e4 LT |
1056 | } |
1057 | ||
1058 | static void pl011_stop_rx(struct uart_port *port) | |
1059 | { | |
1060 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1061 | ||
1062 | uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM| | |
1063 | UART011_PEIM|UART011_BEIM|UART011_OEIM); | |
1064 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
ead76f32 LW |
1065 | |
1066 | pl011_dma_rx_stop(uap); | |
1da177e4 LT |
1067 | } |
1068 | ||
1069 | static void pl011_enable_ms(struct uart_port *port) | |
1070 | { | |
1071 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1072 | ||
1073 | uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM; | |
1074 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
1075 | } | |
1076 | ||
7d12e780 | 1077 | static void pl011_rx_chars(struct uart_amba_port *uap) |
1da177e4 | 1078 | { |
ebd2c8f6 | 1079 | struct tty_struct *tty = uap->port.state->port.tty; |
1da177e4 | 1080 | |
29772c4e | 1081 | pl011_fifo_to_tty(uap); |
1da177e4 | 1082 | |
2389b272 | 1083 | spin_unlock(&uap->port.lock); |
1da177e4 | 1084 | tty_flip_buffer_push(tty); |
ead76f32 LW |
1085 | /* |
1086 | * If we were temporarily out of DMA mode for a while, | |
1087 | * attempt to switch back to DMA mode again. | |
1088 | */ | |
1089 | if (pl011_dma_rx_available(uap)) { | |
1090 | if (pl011_dma_rx_trigger_dma(uap)) { | |
1091 | dev_dbg(uap->port.dev, "could not trigger RX DMA job " | |
1092 | "fall back to interrupt mode again\n"); | |
1093 | uap->im |= UART011_RXIM; | |
1094 | } else | |
1095 | uap->im &= ~UART011_RXIM; | |
1096 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
1097 | } | |
2389b272 | 1098 | spin_lock(&uap->port.lock); |
1da177e4 LT |
1099 | } |
1100 | ||
1101 | static void pl011_tx_chars(struct uart_amba_port *uap) | |
1102 | { | |
ebd2c8f6 | 1103 | struct circ_buf *xmit = &uap->port.state->xmit; |
1da177e4 LT |
1104 | int count; |
1105 | ||
1106 | if (uap->port.x_char) { | |
1107 | writew(uap->port.x_char, uap->port.membase + UART01x_DR); | |
1108 | uap->port.icount.tx++; | |
1109 | uap->port.x_char = 0; | |
1110 | return; | |
1111 | } | |
1112 | if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) { | |
b129a8cc | 1113 | pl011_stop_tx(&uap->port); |
1da177e4 LT |
1114 | return; |
1115 | } | |
1116 | ||
68b65f73 RK |
1117 | /* If we are using DMA mode, try to send some characters. */ |
1118 | if (pl011_dma_tx_irq(uap)) | |
1119 | return; | |
1120 | ||
ffca2b11 | 1121 | count = uap->fifosize >> 1; |
1da177e4 LT |
1122 | do { |
1123 | writew(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR); | |
1124 | xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); | |
1125 | uap->port.icount.tx++; | |
1126 | if (uart_circ_empty(xmit)) | |
1127 | break; | |
1128 | } while (--count > 0); | |
1129 | ||
1130 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) | |
1131 | uart_write_wakeup(&uap->port); | |
1132 | ||
1133 | if (uart_circ_empty(xmit)) | |
b129a8cc | 1134 | pl011_stop_tx(&uap->port); |
1da177e4 LT |
1135 | } |
1136 | ||
1137 | static void pl011_modem_status(struct uart_amba_port *uap) | |
1138 | { | |
1139 | unsigned int status, delta; | |
1140 | ||
1141 | status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY; | |
1142 | ||
1143 | delta = status ^ uap->old_status; | |
1144 | uap->old_status = status; | |
1145 | ||
1146 | if (!delta) | |
1147 | return; | |
1148 | ||
1149 | if (delta & UART01x_FR_DCD) | |
1150 | uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD); | |
1151 | ||
1152 | if (delta & UART01x_FR_DSR) | |
1153 | uap->port.icount.dsr++; | |
1154 | ||
1155 | if (delta & UART01x_FR_CTS) | |
1156 | uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS); | |
1157 | ||
bdc04e31 | 1158 | wake_up_interruptible(&uap->port.state->port.delta_msr_wait); |
1da177e4 LT |
1159 | } |
1160 | ||
7d12e780 | 1161 | static irqreturn_t pl011_int(int irq, void *dev_id) |
1da177e4 LT |
1162 | { |
1163 | struct uart_amba_port *uap = dev_id; | |
963cc981 | 1164 | unsigned long flags; |
1da177e4 LT |
1165 | unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT; |
1166 | int handled = 0; | |
4fd0690b | 1167 | unsigned int dummy_read; |
1da177e4 | 1168 | |
963cc981 | 1169 | spin_lock_irqsave(&uap->port.lock, flags); |
1da177e4 LT |
1170 | |
1171 | status = readw(uap->port.membase + UART011_MIS); | |
1172 | if (status) { | |
1173 | do { | |
4fd0690b R |
1174 | if (uap->vendor->cts_event_workaround) { |
1175 | /* workaround to make sure that all bits are unlocked.. */ | |
1176 | writew(0x00, uap->port.membase + UART011_ICR); | |
1177 | ||
1178 | /* | |
1179 | * WA: introduce 26ns(1 uart clk) delay before W1C; | |
1180 | * single apb access will incur 2 pclk(133.12Mhz) delay, | |
1181 | * so add 2 dummy reads | |
1182 | */ | |
1183 | dummy_read = readw(uap->port.membase + UART011_ICR); | |
1184 | dummy_read = readw(uap->port.membase + UART011_ICR); | |
1185 | } | |
1186 | ||
1da177e4 LT |
1187 | writew(status & ~(UART011_TXIS|UART011_RTIS| |
1188 | UART011_RXIS), | |
1189 | uap->port.membase + UART011_ICR); | |
1190 | ||
ead76f32 LW |
1191 | if (status & (UART011_RTIS|UART011_RXIS)) { |
1192 | if (pl011_dma_rx_running(uap)) | |
1193 | pl011_dma_rx_irq(uap); | |
1194 | else | |
1195 | pl011_rx_chars(uap); | |
1196 | } | |
1da177e4 LT |
1197 | if (status & (UART011_DSRMIS|UART011_DCDMIS| |
1198 | UART011_CTSMIS|UART011_RIMIS)) | |
1199 | pl011_modem_status(uap); | |
1200 | if (status & UART011_TXIS) | |
1201 | pl011_tx_chars(uap); | |
1202 | ||
4fd0690b | 1203 | if (pass_counter-- == 0) |
1da177e4 LT |
1204 | break; |
1205 | ||
1206 | status = readw(uap->port.membase + UART011_MIS); | |
1207 | } while (status != 0); | |
1208 | handled = 1; | |
1209 | } | |
1210 | ||
963cc981 | 1211 | spin_unlock_irqrestore(&uap->port.lock, flags); |
1da177e4 LT |
1212 | |
1213 | return IRQ_RETVAL(handled); | |
1214 | } | |
1215 | ||
e643f87f | 1216 | static unsigned int pl011_tx_empty(struct uart_port *port) |
1da177e4 LT |
1217 | { |
1218 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1219 | unsigned int status = readw(uap->port.membase + UART01x_FR); | |
1220 | return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT; | |
1221 | } | |
1222 | ||
e643f87f | 1223 | static unsigned int pl011_get_mctrl(struct uart_port *port) |
1da177e4 LT |
1224 | { |
1225 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1226 | unsigned int result = 0; | |
1227 | unsigned int status = readw(uap->port.membase + UART01x_FR); | |
1228 | ||
5159f407 | 1229 | #define TIOCMBIT(uartbit, tiocmbit) \ |
1da177e4 LT |
1230 | if (status & uartbit) \ |
1231 | result |= tiocmbit | |
1232 | ||
5159f407 JS |
1233 | TIOCMBIT(UART01x_FR_DCD, TIOCM_CAR); |
1234 | TIOCMBIT(UART01x_FR_DSR, TIOCM_DSR); | |
1235 | TIOCMBIT(UART01x_FR_CTS, TIOCM_CTS); | |
1236 | TIOCMBIT(UART011_FR_RI, TIOCM_RNG); | |
1237 | #undef TIOCMBIT | |
1da177e4 LT |
1238 | return result; |
1239 | } | |
1240 | ||
1241 | static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl) | |
1242 | { | |
1243 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1244 | unsigned int cr; | |
1245 | ||
1246 | cr = readw(uap->port.membase + UART011_CR); | |
1247 | ||
5159f407 | 1248 | #define TIOCMBIT(tiocmbit, uartbit) \ |
1da177e4 LT |
1249 | if (mctrl & tiocmbit) \ |
1250 | cr |= uartbit; \ | |
1251 | else \ | |
1252 | cr &= ~uartbit | |
1253 | ||
5159f407 JS |
1254 | TIOCMBIT(TIOCM_RTS, UART011_CR_RTS); |
1255 | TIOCMBIT(TIOCM_DTR, UART011_CR_DTR); | |
1256 | TIOCMBIT(TIOCM_OUT1, UART011_CR_OUT1); | |
1257 | TIOCMBIT(TIOCM_OUT2, UART011_CR_OUT2); | |
1258 | TIOCMBIT(TIOCM_LOOP, UART011_CR_LBE); | |
3b43816f RV |
1259 | |
1260 | if (uap->autorts) { | |
1261 | /* We need to disable auto-RTS if we want to turn RTS off */ | |
1262 | TIOCMBIT(TIOCM_RTS, UART011_CR_RTSEN); | |
1263 | } | |
5159f407 | 1264 | #undef TIOCMBIT |
1da177e4 LT |
1265 | |
1266 | writew(cr, uap->port.membase + UART011_CR); | |
1267 | } | |
1268 | ||
1269 | static void pl011_break_ctl(struct uart_port *port, int break_state) | |
1270 | { | |
1271 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1272 | unsigned long flags; | |
1273 | unsigned int lcr_h; | |
1274 | ||
1275 | spin_lock_irqsave(&uap->port.lock, flags); | |
ec489aa8 | 1276 | lcr_h = readw(uap->port.membase + uap->lcrh_tx); |
1da177e4 LT |
1277 | if (break_state == -1) |
1278 | lcr_h |= UART01x_LCRH_BRK; | |
1279 | else | |
1280 | lcr_h &= ~UART01x_LCRH_BRK; | |
ec489aa8 | 1281 | writew(lcr_h, uap->port.membase + uap->lcrh_tx); |
1da177e4 LT |
1282 | spin_unlock_irqrestore(&uap->port.lock, flags); |
1283 | } | |
1284 | ||
84b5ae15 | 1285 | #ifdef CONFIG_CONSOLE_POLL |
5c8124a0 AV |
1286 | |
1287 | static void pl011_quiesce_irqs(struct uart_port *port) | |
1288 | { | |
1289 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1290 | unsigned char __iomem *regs = uap->port.membase; | |
1291 | ||
1292 | writew(readw(regs + UART011_MIS), regs + UART011_ICR); | |
1293 | /* | |
1294 | * There is no way to clear TXIM as this is "ready to transmit IRQ", so | |
1295 | * we simply mask it. start_tx() will unmask it. | |
1296 | * | |
1297 | * Note we can race with start_tx(), and if the race happens, the | |
1298 | * polling user might get another interrupt just after we clear it. | |
1299 | * But it should be OK and can happen even w/o the race, e.g. | |
1300 | * controller immediately got some new data and raised the IRQ. | |
1301 | * | |
1302 | * And whoever uses polling routines assumes that it manages the device | |
1303 | * (including tx queue), so we're also fine with start_tx()'s caller | |
1304 | * side. | |
1305 | */ | |
1306 | writew(readw(regs + UART011_IMSC) & ~UART011_TXIM, regs + UART011_IMSC); | |
1307 | } | |
1308 | ||
e643f87f | 1309 | static int pl011_get_poll_char(struct uart_port *port) |
84b5ae15 JW |
1310 | { |
1311 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1312 | unsigned int status; | |
1313 | ||
5c8124a0 AV |
1314 | /* |
1315 | * The caller might need IRQs lowered, e.g. if used with KDB NMI | |
1316 | * debugger. | |
1317 | */ | |
1318 | pl011_quiesce_irqs(port); | |
1319 | ||
f5316b4a JW |
1320 | status = readw(uap->port.membase + UART01x_FR); |
1321 | if (status & UART01x_FR_RXFE) | |
1322 | return NO_POLL_CHAR; | |
84b5ae15 JW |
1323 | |
1324 | return readw(uap->port.membase + UART01x_DR); | |
1325 | } | |
1326 | ||
e643f87f | 1327 | static void pl011_put_poll_char(struct uart_port *port, |
84b5ae15 JW |
1328 | unsigned char ch) |
1329 | { | |
1330 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1331 | ||
1332 | while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF) | |
1333 | barrier(); | |
1334 | ||
1335 | writew(ch, uap->port.membase + UART01x_DR); | |
1336 | } | |
1337 | ||
1338 | #endif /* CONFIG_CONSOLE_POLL */ | |
1339 | ||
b3564c2c | 1340 | static int pl011_hwinit(struct uart_port *port) |
1da177e4 LT |
1341 | { |
1342 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1da177e4 LT |
1343 | int retval; |
1344 | ||
78d80c5a LW |
1345 | /* Optionaly enable pins to be muxed in and configured */ |
1346 | if (!IS_ERR(uap->pins_default)) { | |
1347 | retval = pinctrl_select_state(uap->pinctrl, uap->pins_default); | |
1348 | if (retval) | |
1349 | dev_err(port->dev, | |
1350 | "could not set default pins\n"); | |
1351 | } | |
1352 | ||
1da177e4 LT |
1353 | /* |
1354 | * Try to enable the clock producer. | |
1355 | */ | |
1c4c4394 | 1356 | retval = clk_prepare_enable(uap->clk); |
1da177e4 | 1357 | if (retval) |
1c4c4394 | 1358 | goto out; |
1da177e4 LT |
1359 | |
1360 | uap->port.uartclk = clk_get_rate(uap->clk); | |
1361 | ||
9b96fbac LW |
1362 | /* Clear pending error and receive interrupts */ |
1363 | writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS | | |
1364 | UART011_RTIS | UART011_RXIS, uap->port.membase + UART011_ICR); | |
1365 | ||
b3564c2c AV |
1366 | /* |
1367 | * Save interrupts enable mask, and enable RX interrupts in case if | |
1368 | * the interrupt is used for NMI entry. | |
1369 | */ | |
1370 | uap->im = readw(uap->port.membase + UART011_IMSC); | |
1371 | writew(UART011_RTIM | UART011_RXIM, uap->port.membase + UART011_IMSC); | |
1372 | ||
1373 | if (uap->port.dev->platform_data) { | |
1374 | struct amba_pl011_data *plat; | |
1375 | ||
1376 | plat = uap->port.dev->platform_data; | |
1377 | if (plat->init) | |
1378 | plat->init(); | |
1379 | } | |
1380 | return 0; | |
1381 | out: | |
1382 | return retval; | |
1383 | } | |
1384 | ||
1385 | static int pl011_startup(struct uart_port *port) | |
1386 | { | |
1387 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
1388 | unsigned int cr; | |
1389 | int retval; | |
1390 | ||
1391 | retval = pl011_hwinit(port); | |
1392 | if (retval) | |
1393 | goto clk_dis; | |
1394 | ||
1395 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
1396 | ||
1da177e4 LT |
1397 | /* |
1398 | * Allocate the IRQ | |
1399 | */ | |
1400 | retval = request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap); | |
1401 | if (retval) | |
1402 | goto clk_dis; | |
1403 | ||
c19f12b5 | 1404 | writew(uap->vendor->ifls, uap->port.membase + UART011_IFLS); |
1da177e4 LT |
1405 | |
1406 | /* | |
1407 | * Provoke TX FIFO interrupt into asserting. | |
1408 | */ | |
1409 | cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE; | |
1410 | writew(cr, uap->port.membase + UART011_CR); | |
1411 | writew(0, uap->port.membase + UART011_FBRD); | |
1412 | writew(1, uap->port.membase + UART011_IBRD); | |
ec489aa8 LW |
1413 | writew(0, uap->port.membase + uap->lcrh_rx); |
1414 | if (uap->lcrh_tx != uap->lcrh_rx) { | |
1415 | int i; | |
1416 | /* | |
1417 | * Wait 10 PCLKs before writing LCRH_TX register, | |
1418 | * to get this delay write read only register 10 times | |
1419 | */ | |
1420 | for (i = 0; i < 10; ++i) | |
1421 | writew(0xff, uap->port.membase + UART011_MIS); | |
1422 | writew(0, uap->port.membase + uap->lcrh_tx); | |
1423 | } | |
1da177e4 LT |
1424 | writew(0, uap->port.membase + UART01x_DR); |
1425 | while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY) | |
1426 | barrier(); | |
1427 | ||
d8d8ffa4 SKS |
1428 | /* restore RTS and DTR */ |
1429 | cr = uap->old_cr & (UART011_CR_RTS | UART011_CR_DTR); | |
1430 | cr |= UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE; | |
1da177e4 LT |
1431 | writew(cr, uap->port.membase + UART011_CR); |
1432 | ||
1433 | /* | |
1434 | * initialise the old status of the modem signals | |
1435 | */ | |
1436 | uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY; | |
1437 | ||
68b65f73 RK |
1438 | /* Startup DMA */ |
1439 | pl011_dma_startup(uap); | |
1440 | ||
1da177e4 | 1441 | /* |
ead76f32 LW |
1442 | * Finally, enable interrupts, only timeouts when using DMA |
1443 | * if initial RX DMA job failed, start in interrupt mode | |
1444 | * as well. | |
1da177e4 LT |
1445 | */ |
1446 | spin_lock_irq(&uap->port.lock); | |
9b96fbac LW |
1447 | /* Clear out any spuriously appearing RX interrupts */ |
1448 | writew(UART011_RTIS | UART011_RXIS, | |
1449 | uap->port.membase + UART011_ICR); | |
ead76f32 LW |
1450 | uap->im = UART011_RTIM; |
1451 | if (!pl011_dma_rx_running(uap)) | |
1452 | uap->im |= UART011_RXIM; | |
1da177e4 LT |
1453 | writew(uap->im, uap->port.membase + UART011_IMSC); |
1454 | spin_unlock_irq(&uap->port.lock); | |
1455 | ||
1456 | return 0; | |
1457 | ||
1458 | clk_dis: | |
1c4c4394 | 1459 | clk_disable_unprepare(uap->clk); |
1da177e4 LT |
1460 | return retval; |
1461 | } | |
1462 | ||
ec489aa8 LW |
1463 | static void pl011_shutdown_channel(struct uart_amba_port *uap, |
1464 | unsigned int lcrh) | |
1465 | { | |
1466 | unsigned long val; | |
1467 | ||
1468 | val = readw(uap->port.membase + lcrh); | |
1469 | val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN); | |
1470 | writew(val, uap->port.membase + lcrh); | |
1471 | } | |
1472 | ||
1da177e4 LT |
1473 | static void pl011_shutdown(struct uart_port *port) |
1474 | { | |
1475 | struct uart_amba_port *uap = (struct uart_amba_port *)port; | |
d8d8ffa4 | 1476 | unsigned int cr; |
78d80c5a | 1477 | int retval; |
1da177e4 LT |
1478 | |
1479 | /* | |
1480 | * disable all interrupts | |
1481 | */ | |
1482 | spin_lock_irq(&uap->port.lock); | |
1483 | uap->im = 0; | |
1484 | writew(uap->im, uap->port.membase + UART011_IMSC); | |
1485 | writew(0xffff, uap->port.membase + UART011_ICR); | |
1486 | spin_unlock_irq(&uap->port.lock); | |
1487 | ||
68b65f73 RK |
1488 | pl011_dma_shutdown(uap); |
1489 | ||
1da177e4 LT |
1490 | /* |
1491 | * Free the interrupt | |
1492 | */ | |
1493 | free_irq(uap->port.irq, uap); | |
1494 | ||
1495 | /* | |
1496 | * disable the port | |
d8d8ffa4 SKS |
1497 | * disable the port. It should not disable RTS and DTR. |
1498 | * Also RTS and DTR state should be preserved to restore | |
1499 | * it during startup(). | |
1da177e4 | 1500 | */ |
3b43816f | 1501 | uap->autorts = false; |
d8d8ffa4 SKS |
1502 | cr = readw(uap->port.membase + UART011_CR); |
1503 | uap->old_cr = cr; | |
1504 | cr &= UART011_CR_RTS | UART011_CR_DTR; | |
1505 | cr |= UART01x_CR_UARTEN | UART011_CR_TXE; | |
1506 | writew(cr, uap->port.membase + UART011_CR); | |
1da177e4 LT |
1507 | |
1508 | /* | |
1509 | * disable break condition and fifos | |
1510 | */ | |
ec489aa8 LW |
1511 | pl011_shutdown_channel(uap, uap->lcrh_rx); |
1512 | if (uap->lcrh_rx != uap->lcrh_tx) | |
1513 | pl011_shutdown_channel(uap, uap->lcrh_tx); | |
1da177e4 LT |
1514 | |
1515 | /* | |
1516 | * Shut down the clock producer | |
1517 | */ | |
1c4c4394 | 1518 | clk_disable_unprepare(uap->clk); |
78d80c5a LW |
1519 | /* Optionally let pins go into sleep states */ |
1520 | if (!IS_ERR(uap->pins_sleep)) { | |
1521 | retval = pinctrl_select_state(uap->pinctrl, uap->pins_sleep); | |
1522 | if (retval) | |
1523 | dev_err(port->dev, | |
1524 | "could not set pins to sleep state\n"); | |
1525 | } | |
1526 | ||
c16d51a3 SKS |
1527 | |
1528 | if (uap->port.dev->platform_data) { | |
1529 | struct amba_pl011_data *plat; | |
1530 | ||
1531 | plat = uap->port.dev->platform_data; | |
1532 | if (plat->exit) | |
1533 | plat->exit(); | |
1534 | } | |
1535 | ||
1da177e4 LT |
1536 | } |
1537 | ||
1538 | static void | |
606d099c AC |
1539 | pl011_set_termios(struct uart_port *port, struct ktermios *termios, |
1540 | struct ktermios *old) | |
1da177e4 | 1541 | { |
3b43816f | 1542 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
1da177e4 LT |
1543 | unsigned int lcr_h, old_cr; |
1544 | unsigned long flags; | |
c19f12b5 RK |
1545 | unsigned int baud, quot, clkdiv; |
1546 | ||
1547 | if (uap->vendor->oversampling) | |
1548 | clkdiv = 8; | |
1549 | else | |
1550 | clkdiv = 16; | |
1da177e4 LT |
1551 | |
1552 | /* | |
1553 | * Ask the core to calculate the divisor for us. | |
1554 | */ | |
ac3e3fb4 | 1555 | baud = uart_get_baud_rate(port, termios, old, 0, |
c19f12b5 | 1556 | port->uartclk / clkdiv); |
ac3e3fb4 LW |
1557 | |
1558 | if (baud > port->uartclk/16) | |
1559 | quot = DIV_ROUND_CLOSEST(port->uartclk * 8, baud); | |
1560 | else | |
1561 | quot = DIV_ROUND_CLOSEST(port->uartclk * 4, baud); | |
1da177e4 LT |
1562 | |
1563 | switch (termios->c_cflag & CSIZE) { | |
1564 | case CS5: | |
1565 | lcr_h = UART01x_LCRH_WLEN_5; | |
1566 | break; | |
1567 | case CS6: | |
1568 | lcr_h = UART01x_LCRH_WLEN_6; | |
1569 | break; | |
1570 | case CS7: | |
1571 | lcr_h = UART01x_LCRH_WLEN_7; | |
1572 | break; | |
1573 | default: // CS8 | |
1574 | lcr_h = UART01x_LCRH_WLEN_8; | |
1575 | break; | |
1576 | } | |
1577 | if (termios->c_cflag & CSTOPB) | |
1578 | lcr_h |= UART01x_LCRH_STP2; | |
1579 | if (termios->c_cflag & PARENB) { | |
1580 | lcr_h |= UART01x_LCRH_PEN; | |
1581 | if (!(termios->c_cflag & PARODD)) | |
1582 | lcr_h |= UART01x_LCRH_EPS; | |
1583 | } | |
ffca2b11 | 1584 | if (uap->fifosize > 1) |
1da177e4 LT |
1585 | lcr_h |= UART01x_LCRH_FEN; |
1586 | ||
1587 | spin_lock_irqsave(&port->lock, flags); | |
1588 | ||
1589 | /* | |
1590 | * Update the per-port timeout. | |
1591 | */ | |
1592 | uart_update_timeout(port, termios->c_cflag, baud); | |
1593 | ||
b63d4f0f | 1594 | port->read_status_mask = UART011_DR_OE | 255; |
1da177e4 | 1595 | if (termios->c_iflag & INPCK) |
b63d4f0f | 1596 | port->read_status_mask |= UART011_DR_FE | UART011_DR_PE; |
1da177e4 | 1597 | if (termios->c_iflag & (BRKINT | PARMRK)) |
b63d4f0f | 1598 | port->read_status_mask |= UART011_DR_BE; |
1da177e4 LT |
1599 | |
1600 | /* | |
1601 | * Characters to ignore | |
1602 | */ | |
1603 | port->ignore_status_mask = 0; | |
1604 | if (termios->c_iflag & IGNPAR) | |
b63d4f0f | 1605 | port->ignore_status_mask |= UART011_DR_FE | UART011_DR_PE; |
1da177e4 | 1606 | if (termios->c_iflag & IGNBRK) { |
b63d4f0f | 1607 | port->ignore_status_mask |= UART011_DR_BE; |
1da177e4 LT |
1608 | /* |
1609 | * If we're ignoring parity and break indicators, | |
1610 | * ignore overruns too (for real raw support). | |
1611 | */ | |
1612 | if (termios->c_iflag & IGNPAR) | |
b63d4f0f | 1613 | port->ignore_status_mask |= UART011_DR_OE; |
1da177e4 LT |
1614 | } |
1615 | ||
1616 | /* | |
1617 | * Ignore all characters if CREAD is not set. | |
1618 | */ | |
1619 | if ((termios->c_cflag & CREAD) == 0) | |
b63d4f0f | 1620 | port->ignore_status_mask |= UART_DUMMY_DR_RX; |
1da177e4 LT |
1621 | |
1622 | if (UART_ENABLE_MS(port, termios->c_cflag)) | |
1623 | pl011_enable_ms(port); | |
1624 | ||
1625 | /* first, disable everything */ | |
1626 | old_cr = readw(port->membase + UART011_CR); | |
1627 | writew(0, port->membase + UART011_CR); | |
1628 | ||
3b43816f RV |
1629 | if (termios->c_cflag & CRTSCTS) { |
1630 | if (old_cr & UART011_CR_RTS) | |
1631 | old_cr |= UART011_CR_RTSEN; | |
1632 | ||
1633 | old_cr |= UART011_CR_CTSEN; | |
1634 | uap->autorts = true; | |
1635 | } else { | |
1636 | old_cr &= ~(UART011_CR_CTSEN | UART011_CR_RTSEN); | |
1637 | uap->autorts = false; | |
1638 | } | |
1639 | ||
c19f12b5 RK |
1640 | if (uap->vendor->oversampling) { |
1641 | if (baud > port->uartclk / 16) | |
ac3e3fb4 LW |
1642 | old_cr |= ST_UART011_CR_OVSFACT; |
1643 | else | |
1644 | old_cr &= ~ST_UART011_CR_OVSFACT; | |
1645 | } | |
1646 | ||
c5dd553b LW |
1647 | /* |
1648 | * Workaround for the ST Micro oversampling variants to | |
1649 | * increase the bitrate slightly, by lowering the divisor, | |
1650 | * to avoid delayed sampling of start bit at high speeds, | |
1651 | * else we see data corruption. | |
1652 | */ | |
1653 | if (uap->vendor->oversampling) { | |
1654 | if ((baud >= 3000000) && (baud < 3250000) && (quot > 1)) | |
1655 | quot -= 1; | |
1656 | else if ((baud > 3250000) && (quot > 2)) | |
1657 | quot -= 2; | |
1658 | } | |
1da177e4 LT |
1659 | /* Set baud rate */ |
1660 | writew(quot & 0x3f, port->membase + UART011_FBRD); | |
1661 | writew(quot >> 6, port->membase + UART011_IBRD); | |
1662 | ||
1663 | /* | |
1664 | * ----------v----------v----------v----------v----- | |
c5dd553b LW |
1665 | * NOTE: lcrh_tx and lcrh_rx MUST BE WRITTEN AFTER |
1666 | * UART011_FBRD & UART011_IBRD. | |
1da177e4 LT |
1667 | * ----------^----------^----------^----------^----- |
1668 | */ | |
ec489aa8 LW |
1669 | writew(lcr_h, port->membase + uap->lcrh_rx); |
1670 | if (uap->lcrh_rx != uap->lcrh_tx) { | |
1671 | int i; | |
1672 | /* | |
1673 | * Wait 10 PCLKs before writing LCRH_TX register, | |
1674 | * to get this delay write read only register 10 times | |
1675 | */ | |
1676 | for (i = 0; i < 10; ++i) | |
1677 | writew(0xff, uap->port.membase + UART011_MIS); | |
1678 | writew(lcr_h, port->membase + uap->lcrh_tx); | |
1679 | } | |
1da177e4 LT |
1680 | writew(old_cr, port->membase + UART011_CR); |
1681 | ||
1682 | spin_unlock_irqrestore(&port->lock, flags); | |
1683 | } | |
1684 | ||
1685 | static const char *pl011_type(struct uart_port *port) | |
1686 | { | |
e8a7ba86 RK |
1687 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
1688 | return uap->port.type == PORT_AMBA ? uap->type : NULL; | |
1da177e4 LT |
1689 | } |
1690 | ||
1691 | /* | |
1692 | * Release the memory region(s) being used by 'port' | |
1693 | */ | |
e643f87f | 1694 | static void pl011_release_port(struct uart_port *port) |
1da177e4 LT |
1695 | { |
1696 | release_mem_region(port->mapbase, SZ_4K); | |
1697 | } | |
1698 | ||
1699 | /* | |
1700 | * Request the memory region(s) being used by 'port' | |
1701 | */ | |
e643f87f | 1702 | static int pl011_request_port(struct uart_port *port) |
1da177e4 LT |
1703 | { |
1704 | return request_mem_region(port->mapbase, SZ_4K, "uart-pl011") | |
1705 | != NULL ? 0 : -EBUSY; | |
1706 | } | |
1707 | ||
1708 | /* | |
1709 | * Configure/autoconfigure the port. | |
1710 | */ | |
e643f87f | 1711 | static void pl011_config_port(struct uart_port *port, int flags) |
1da177e4 LT |
1712 | { |
1713 | if (flags & UART_CONFIG_TYPE) { | |
1714 | port->type = PORT_AMBA; | |
e643f87f | 1715 | pl011_request_port(port); |
1da177e4 LT |
1716 | } |
1717 | } | |
1718 | ||
1719 | /* | |
1720 | * verify the new serial_struct (for TIOCSSERIAL). | |
1721 | */ | |
e643f87f | 1722 | static int pl011_verify_port(struct uart_port *port, struct serial_struct *ser) |
1da177e4 LT |
1723 | { |
1724 | int ret = 0; | |
1725 | if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA) | |
1726 | ret = -EINVAL; | |
a62c4133 | 1727 | if (ser->irq < 0 || ser->irq >= nr_irqs) |
1da177e4 LT |
1728 | ret = -EINVAL; |
1729 | if (ser->baud_base < 9600) | |
1730 | ret = -EINVAL; | |
1731 | return ret; | |
1732 | } | |
1733 | ||
1734 | static struct uart_ops amba_pl011_pops = { | |
e643f87f | 1735 | .tx_empty = pl011_tx_empty, |
1da177e4 | 1736 | .set_mctrl = pl011_set_mctrl, |
e643f87f | 1737 | .get_mctrl = pl011_get_mctrl, |
1da177e4 LT |
1738 | .stop_tx = pl011_stop_tx, |
1739 | .start_tx = pl011_start_tx, | |
1740 | .stop_rx = pl011_stop_rx, | |
1741 | .enable_ms = pl011_enable_ms, | |
1742 | .break_ctl = pl011_break_ctl, | |
1743 | .startup = pl011_startup, | |
1744 | .shutdown = pl011_shutdown, | |
68b65f73 | 1745 | .flush_buffer = pl011_dma_flush_buffer, |
1da177e4 LT |
1746 | .set_termios = pl011_set_termios, |
1747 | .type = pl011_type, | |
e643f87f LW |
1748 | .release_port = pl011_release_port, |
1749 | .request_port = pl011_request_port, | |
1750 | .config_port = pl011_config_port, | |
1751 | .verify_port = pl011_verify_port, | |
84b5ae15 | 1752 | #ifdef CONFIG_CONSOLE_POLL |
b3564c2c | 1753 | .poll_init = pl011_hwinit, |
e643f87f LW |
1754 | .poll_get_char = pl011_get_poll_char, |
1755 | .poll_put_char = pl011_put_poll_char, | |
84b5ae15 | 1756 | #endif |
1da177e4 LT |
1757 | }; |
1758 | ||
1759 | static struct uart_amba_port *amba_ports[UART_NR]; | |
1760 | ||
1761 | #ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE | |
1762 | ||
d358788f | 1763 | static void pl011_console_putchar(struct uart_port *port, int ch) |
1da177e4 | 1764 | { |
d358788f | 1765 | struct uart_amba_port *uap = (struct uart_amba_port *)port; |
1da177e4 | 1766 | |
d358788f RK |
1767 | while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF) |
1768 | barrier(); | |
1da177e4 LT |
1769 | writew(ch, uap->port.membase + UART01x_DR); |
1770 | } | |
1771 | ||
1772 | static void | |
1773 | pl011_console_write(struct console *co, const char *s, unsigned int count) | |
1774 | { | |
1775 | struct uart_amba_port *uap = amba_ports[co->index]; | |
1776 | unsigned int status, old_cr, new_cr; | |
ef605fdb RV |
1777 | unsigned long flags; |
1778 | int locked = 1; | |
1da177e4 LT |
1779 | |
1780 | clk_enable(uap->clk); | |
1781 | ||
ef605fdb RV |
1782 | local_irq_save(flags); |
1783 | if (uap->port.sysrq) | |
1784 | locked = 0; | |
1785 | else if (oops_in_progress) | |
1786 | locked = spin_trylock(&uap->port.lock); | |
1787 | else | |
1788 | spin_lock(&uap->port.lock); | |
1789 | ||
1da177e4 LT |
1790 | /* |
1791 | * First save the CR then disable the interrupts | |
1792 | */ | |
1793 | old_cr = readw(uap->port.membase + UART011_CR); | |
1794 | new_cr = old_cr & ~UART011_CR_CTSEN; | |
1795 | new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE; | |
1796 | writew(new_cr, uap->port.membase + UART011_CR); | |
1797 | ||
d358788f | 1798 | uart_console_write(&uap->port, s, count, pl011_console_putchar); |
1da177e4 LT |
1799 | |
1800 | /* | |
1801 | * Finally, wait for transmitter to become empty | |
1802 | * and restore the TCR | |
1803 | */ | |
1804 | do { | |
1805 | status = readw(uap->port.membase + UART01x_FR); | |
1806 | } while (status & UART01x_FR_BUSY); | |
1807 | writew(old_cr, uap->port.membase + UART011_CR); | |
1808 | ||
ef605fdb RV |
1809 | if (locked) |
1810 | spin_unlock(&uap->port.lock); | |
1811 | local_irq_restore(flags); | |
1812 | ||
1da177e4 LT |
1813 | clk_disable(uap->clk); |
1814 | } | |
1815 | ||
1816 | static void __init | |
1817 | pl011_console_get_options(struct uart_amba_port *uap, int *baud, | |
1818 | int *parity, int *bits) | |
1819 | { | |
1820 | if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) { | |
1821 | unsigned int lcr_h, ibrd, fbrd; | |
1822 | ||
ec489aa8 | 1823 | lcr_h = readw(uap->port.membase + uap->lcrh_tx); |
1da177e4 LT |
1824 | |
1825 | *parity = 'n'; | |
1826 | if (lcr_h & UART01x_LCRH_PEN) { | |
1827 | if (lcr_h & UART01x_LCRH_EPS) | |
1828 | *parity = 'e'; | |
1829 | else | |
1830 | *parity = 'o'; | |
1831 | } | |
1832 | ||
1833 | if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7) | |
1834 | *bits = 7; | |
1835 | else | |
1836 | *bits = 8; | |
1837 | ||
1838 | ibrd = readw(uap->port.membase + UART011_IBRD); | |
1839 | fbrd = readw(uap->port.membase + UART011_FBRD); | |
1840 | ||
1841 | *baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd); | |
ac3e3fb4 | 1842 | |
c19f12b5 | 1843 | if (uap->vendor->oversampling) { |
ac3e3fb4 LW |
1844 | if (readw(uap->port.membase + UART011_CR) |
1845 | & ST_UART011_CR_OVSFACT) | |
1846 | *baud *= 2; | |
1847 | } | |
1da177e4 LT |
1848 | } |
1849 | } | |
1850 | ||
1851 | static int __init pl011_console_setup(struct console *co, char *options) | |
1852 | { | |
1853 | struct uart_amba_port *uap; | |
1854 | int baud = 38400; | |
1855 | int bits = 8; | |
1856 | int parity = 'n'; | |
1857 | int flow = 'n'; | |
4b4851c6 | 1858 | int ret; |
1da177e4 LT |
1859 | |
1860 | /* | |
1861 | * Check whether an invalid uart number has been specified, and | |
1862 | * if so, search for the first available port that does have | |
1863 | * console support. | |
1864 | */ | |
1865 | if (co->index >= UART_NR) | |
1866 | co->index = 0; | |
1867 | uap = amba_ports[co->index]; | |
d28122a5 RK |
1868 | if (!uap) |
1869 | return -ENODEV; | |
1da177e4 | 1870 | |
78d80c5a LW |
1871 | /* Allow pins to be muxed in and configured */ |
1872 | if (!IS_ERR(uap->pins_default)) { | |
1873 | ret = pinctrl_select_state(uap->pinctrl, uap->pins_default); | |
1874 | if (ret) | |
1875 | dev_err(uap->port.dev, | |
1876 | "could not set default pins\n"); | |
1877 | } | |
1878 | ||
4b4851c6 RK |
1879 | ret = clk_prepare(uap->clk); |
1880 | if (ret) | |
1881 | return ret; | |
1882 | ||
c16d51a3 SKS |
1883 | if (uap->port.dev->platform_data) { |
1884 | struct amba_pl011_data *plat; | |
1885 | ||
1886 | plat = uap->port.dev->platform_data; | |
1887 | if (plat->init) | |
1888 | plat->init(); | |
1889 | } | |
1890 | ||
1da177e4 LT |
1891 | uap->port.uartclk = clk_get_rate(uap->clk); |
1892 | ||
1893 | if (options) | |
1894 | uart_parse_options(options, &baud, &parity, &bits, &flow); | |
1895 | else | |
1896 | pl011_console_get_options(uap, &baud, &parity, &bits); | |
1897 | ||
1898 | return uart_set_options(&uap->port, co, baud, parity, bits, flow); | |
1899 | } | |
1900 | ||
2d93486c | 1901 | static struct uart_driver amba_reg; |
1da177e4 LT |
1902 | static struct console amba_console = { |
1903 | .name = "ttyAMA", | |
1904 | .write = pl011_console_write, | |
1905 | .device = uart_console_device, | |
1906 | .setup = pl011_console_setup, | |
1907 | .flags = CON_PRINTBUFFER, | |
1908 | .index = -1, | |
1909 | .data = &amba_reg, | |
1910 | }; | |
1911 | ||
1912 | #define AMBA_CONSOLE (&amba_console) | |
1913 | #else | |
1914 | #define AMBA_CONSOLE NULL | |
1915 | #endif | |
1916 | ||
1917 | static struct uart_driver amba_reg = { | |
1918 | .owner = THIS_MODULE, | |
1919 | .driver_name = "ttyAMA", | |
1920 | .dev_name = "ttyAMA", | |
1921 | .major = SERIAL_AMBA_MAJOR, | |
1922 | .minor = SERIAL_AMBA_MINOR, | |
1923 | .nr = UART_NR, | |
1924 | .cons = AMBA_CONSOLE, | |
1925 | }; | |
1926 | ||
32614aad ML |
1927 | static int pl011_probe_dt_alias(int index, struct device *dev) |
1928 | { | |
1929 | struct device_node *np; | |
1930 | static bool seen_dev_with_alias = false; | |
1931 | static bool seen_dev_without_alias = false; | |
1932 | int ret = index; | |
1933 | ||
1934 | if (!IS_ENABLED(CONFIG_OF)) | |
1935 | return ret; | |
1936 | ||
1937 | np = dev->of_node; | |
1938 | if (!np) | |
1939 | return ret; | |
1940 | ||
1941 | ret = of_alias_get_id(np, "serial"); | |
1942 | if (IS_ERR_VALUE(ret)) { | |
1943 | seen_dev_without_alias = true; | |
1944 | ret = index; | |
1945 | } else { | |
1946 | seen_dev_with_alias = true; | |
1947 | if (ret >= ARRAY_SIZE(amba_ports) || amba_ports[ret] != NULL) { | |
1948 | dev_warn(dev, "requested serial port %d not available.\n", ret); | |
1949 | ret = index; | |
1950 | } | |
1951 | } | |
1952 | ||
1953 | if (seen_dev_with_alias && seen_dev_without_alias) | |
1954 | dev_warn(dev, "aliased and non-aliased serial devices found in device tree. Serial port enumeration may be unpredictable.\n"); | |
1955 | ||
1956 | return ret; | |
1957 | } | |
1958 | ||
aa25afad | 1959 | static int pl011_probe(struct amba_device *dev, const struct amba_id *id) |
1da177e4 LT |
1960 | { |
1961 | struct uart_amba_port *uap; | |
5926a295 | 1962 | struct vendor_data *vendor = id->data; |
1da177e4 LT |
1963 | void __iomem *base; |
1964 | int i, ret; | |
1965 | ||
1966 | for (i = 0; i < ARRAY_SIZE(amba_ports); i++) | |
1967 | if (amba_ports[i] == NULL) | |
1968 | break; | |
1969 | ||
1970 | if (i == ARRAY_SIZE(amba_ports)) { | |
1971 | ret = -EBUSY; | |
1972 | goto out; | |
1973 | } | |
1974 | ||
de609582 LW |
1975 | uap = devm_kzalloc(&dev->dev, sizeof(struct uart_amba_port), |
1976 | GFP_KERNEL); | |
1da177e4 LT |
1977 | if (uap == NULL) { |
1978 | ret = -ENOMEM; | |
1979 | goto out; | |
1980 | } | |
1981 | ||
32614aad ML |
1982 | i = pl011_probe_dt_alias(i, &dev->dev); |
1983 | ||
de609582 LW |
1984 | base = devm_ioremap(&dev->dev, dev->res.start, |
1985 | resource_size(&dev->res)); | |
1da177e4 LT |
1986 | if (!base) { |
1987 | ret = -ENOMEM; | |
de609582 | 1988 | goto out; |
1da177e4 LT |
1989 | } |
1990 | ||
78d80c5a LW |
1991 | uap->pinctrl = devm_pinctrl_get(&dev->dev); |
1992 | if (IS_ERR(uap->pinctrl)) { | |
1993 | ret = PTR_ERR(uap->pinctrl); | |
de609582 | 1994 | goto out; |
258e0551 | 1995 | } |
78d80c5a LW |
1996 | uap->pins_default = pinctrl_lookup_state(uap->pinctrl, |
1997 | PINCTRL_STATE_DEFAULT); | |
1998 | if (IS_ERR(uap->pins_default)) | |
1999 | dev_err(&dev->dev, "could not get default pinstate\n"); | |
2000 | ||
2001 | uap->pins_sleep = pinctrl_lookup_state(uap->pinctrl, | |
2002 | PINCTRL_STATE_SLEEP); | |
2003 | if (IS_ERR(uap->pins_sleep)) | |
2004 | dev_dbg(&dev->dev, "could not get sleep pinstate\n"); | |
258e0551 | 2005 | |
de609582 | 2006 | uap->clk = devm_clk_get(&dev->dev, NULL); |
1da177e4 LT |
2007 | if (IS_ERR(uap->clk)) { |
2008 | ret = PTR_ERR(uap->clk); | |
de609582 | 2009 | goto out; |
1da177e4 LT |
2010 | } |
2011 | ||
c19f12b5 | 2012 | uap->vendor = vendor; |
ec489aa8 LW |
2013 | uap->lcrh_rx = vendor->lcrh_rx; |
2014 | uap->lcrh_tx = vendor->lcrh_tx; | |
d8d8ffa4 | 2015 | uap->old_cr = 0; |
ffca2b11 | 2016 | uap->fifosize = vendor->fifosize; |
1da177e4 LT |
2017 | uap->port.dev = &dev->dev; |
2018 | uap->port.mapbase = dev->res.start; | |
2019 | uap->port.membase = base; | |
2020 | uap->port.iotype = UPIO_MEM; | |
2021 | uap->port.irq = dev->irq[0]; | |
ffca2b11 | 2022 | uap->port.fifosize = uap->fifosize; |
1da177e4 LT |
2023 | uap->port.ops = &amba_pl011_pops; |
2024 | uap->port.flags = UPF_BOOT_AUTOCONF; | |
2025 | uap->port.line = i; | |
68b65f73 | 2026 | pl011_dma_probe(uap); |
1da177e4 | 2027 | |
c3d8b76f LW |
2028 | /* Ensure interrupts from this UART are masked and cleared */ |
2029 | writew(0, uap->port.membase + UART011_IMSC); | |
2030 | writew(0xffff, uap->port.membase + UART011_ICR); | |
2031 | ||
e8a7ba86 RK |
2032 | snprintf(uap->type, sizeof(uap->type), "PL011 rev%u", amba_rev(dev)); |
2033 | ||
1da177e4 LT |
2034 | amba_ports[i] = uap; |
2035 | ||
2036 | amba_set_drvdata(dev, uap); | |
2037 | ret = uart_add_one_port(&amba_reg, &uap->port); | |
2038 | if (ret) { | |
2039 | amba_set_drvdata(dev, NULL); | |
2040 | amba_ports[i] = NULL; | |
68b65f73 | 2041 | pl011_dma_remove(uap); |
1da177e4 LT |
2042 | } |
2043 | out: | |
2044 | return ret; | |
2045 | } | |
2046 | ||
2047 | static int pl011_remove(struct amba_device *dev) | |
2048 | { | |
2049 | struct uart_amba_port *uap = amba_get_drvdata(dev); | |
2050 | int i; | |
2051 | ||
2052 | amba_set_drvdata(dev, NULL); | |
2053 | ||
2054 | uart_remove_one_port(&amba_reg, &uap->port); | |
2055 | ||
2056 | for (i = 0; i < ARRAY_SIZE(amba_ports); i++) | |
2057 | if (amba_ports[i] == uap) | |
2058 | amba_ports[i] = NULL; | |
2059 | ||
68b65f73 | 2060 | pl011_dma_remove(uap); |
1da177e4 LT |
2061 | return 0; |
2062 | } | |
2063 | ||
b736b89f LC |
2064 | #ifdef CONFIG_PM |
2065 | static int pl011_suspend(struct amba_device *dev, pm_message_t state) | |
2066 | { | |
2067 | struct uart_amba_port *uap = amba_get_drvdata(dev); | |
2068 | ||
2069 | if (!uap) | |
2070 | return -EINVAL; | |
2071 | ||
2072 | return uart_suspend_port(&amba_reg, &uap->port); | |
2073 | } | |
2074 | ||
2075 | static int pl011_resume(struct amba_device *dev) | |
2076 | { | |
2077 | struct uart_amba_port *uap = amba_get_drvdata(dev); | |
2078 | ||
2079 | if (!uap) | |
2080 | return -EINVAL; | |
2081 | ||
2082 | return uart_resume_port(&amba_reg, &uap->port); | |
2083 | } | |
2084 | #endif | |
2085 | ||
2c39c9e1 | 2086 | static struct amba_id pl011_ids[] = { |
1da177e4 LT |
2087 | { |
2088 | .id = 0x00041011, | |
2089 | .mask = 0x000fffff, | |
5926a295 AR |
2090 | .data = &vendor_arm, |
2091 | }, | |
2092 | { | |
2093 | .id = 0x00380802, | |
2094 | .mask = 0x00ffffff, | |
2095 | .data = &vendor_st, | |
1da177e4 LT |
2096 | }, |
2097 | { 0, 0 }, | |
2098 | }; | |
2099 | ||
60f7a33b DM |
2100 | MODULE_DEVICE_TABLE(amba, pl011_ids); |
2101 | ||
1da177e4 LT |
2102 | static struct amba_driver pl011_driver = { |
2103 | .drv = { | |
2104 | .name = "uart-pl011", | |
2105 | }, | |
2106 | .id_table = pl011_ids, | |
2107 | .probe = pl011_probe, | |
2108 | .remove = pl011_remove, | |
b736b89f LC |
2109 | #ifdef CONFIG_PM |
2110 | .suspend = pl011_suspend, | |
2111 | .resume = pl011_resume, | |
2112 | #endif | |
1da177e4 LT |
2113 | }; |
2114 | ||
2115 | static int __init pl011_init(void) | |
2116 | { | |
2117 | int ret; | |
2118 | printk(KERN_INFO "Serial: AMBA PL011 UART driver\n"); | |
2119 | ||
2120 | ret = uart_register_driver(&amba_reg); | |
2121 | if (ret == 0) { | |
2122 | ret = amba_driver_register(&pl011_driver); | |
2123 | if (ret) | |
2124 | uart_unregister_driver(&amba_reg); | |
2125 | } | |
2126 | return ret; | |
2127 | } | |
2128 | ||
2129 | static void __exit pl011_exit(void) | |
2130 | { | |
2131 | amba_driver_unregister(&pl011_driver); | |
2132 | uart_unregister_driver(&amba_reg); | |
2133 | } | |
2134 | ||
4dd9e742 AR |
2135 | /* |
2136 | * While this can be a module, if builtin it's most likely the console | |
2137 | * So let's leave module_exit but move module_init to an earlier place | |
2138 | */ | |
2139 | arch_initcall(pl011_init); | |
1da177e4 LT |
2140 | module_exit(pl011_exit); |
2141 | ||
2142 | MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd"); | |
2143 | MODULE_DESCRIPTION("ARM AMBA serial port driver"); | |
2144 | MODULE_LICENSE("GPL"); |