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1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Drivers for CSR SiRFprimaII onboard UARTs.
4  *
5  * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
6  */
7 #include <linux/bitops.h>
8 #include <linux/log2.h>
9 #include <linux/hrtimer.h>
10 struct sirfsoc_uart_param {
11 	const char *uart_name;
12 	const char *port_name;
13 };
14 
15 struct sirfsoc_register {
16 	/* hardware uart specific */
17 	u32 sirfsoc_line_ctrl;
18 	u32 sirfsoc_divisor;
19 	/* uart - usp common */
20 	u32 sirfsoc_tx_rx_en;
21 	u32 sirfsoc_int_en_reg;
22 	u32 sirfsoc_int_st_reg;
23 	u32 sirfsoc_int_en_clr_reg;
24 	u32 sirfsoc_tx_dma_io_ctrl;
25 	u32 sirfsoc_tx_dma_io_len;
26 	u32 sirfsoc_tx_fifo_ctrl;
27 	u32 sirfsoc_tx_fifo_level_chk;
28 	u32 sirfsoc_tx_fifo_op;
29 	u32 sirfsoc_tx_fifo_status;
30 	u32 sirfsoc_tx_fifo_data;
31 	u32 sirfsoc_rx_dma_io_ctrl;
32 	u32 sirfsoc_rx_dma_io_len;
33 	u32 sirfsoc_rx_fifo_ctrl;
34 	u32 sirfsoc_rx_fifo_level_chk;
35 	u32 sirfsoc_rx_fifo_op;
36 	u32 sirfsoc_rx_fifo_status;
37 	u32 sirfsoc_rx_fifo_data;
38 	u32 sirfsoc_afc_ctrl;
39 	u32 sirfsoc_swh_dma_io;
40 	/* hardware usp specific */
41 	u32 sirfsoc_mode1;
42 	u32 sirfsoc_mode2;
43 	u32 sirfsoc_tx_frame_ctrl;
44 	u32 sirfsoc_rx_frame_ctrl;
45 	u32 sirfsoc_async_param_reg;
46 };
47 
48 typedef u32 (*fifo_full_mask)(struct uart_port *port);
49 typedef u32 (*fifo_empty_mask)(struct uart_port *port);
50 
51 struct sirfsoc_fifo_status {
52 	fifo_full_mask ff_full;
53 	fifo_empty_mask ff_empty;
54 };
55 
56 struct sirfsoc_int_en {
57 	u32 sirfsoc_rx_done_en;
58 	u32 sirfsoc_tx_done_en;
59 	u32 sirfsoc_rx_oflow_en;
60 	u32 sirfsoc_tx_allout_en;
61 	u32 sirfsoc_rx_io_dma_en;
62 	u32 sirfsoc_tx_io_dma_en;
63 	u32 sirfsoc_rxfifo_full_en;
64 	u32 sirfsoc_txfifo_empty_en;
65 	u32 sirfsoc_rxfifo_thd_en;
66 	u32 sirfsoc_txfifo_thd_en;
67 	u32 sirfsoc_frm_err_en;
68 	u32 sirfsoc_rxd_brk_en;
69 	u32 sirfsoc_rx_timeout_en;
70 	u32 sirfsoc_parity_err_en;
71 	u32 sirfsoc_cts_en;
72 	u32 sirfsoc_rts_en;
73 };
74 
75 struct sirfsoc_int_status {
76 	u32 sirfsoc_rx_done;
77 	u32 sirfsoc_tx_done;
78 	u32 sirfsoc_rx_oflow;
79 	u32 sirfsoc_tx_allout;
80 	u32 sirfsoc_rx_io_dma;
81 	u32 sirfsoc_tx_io_dma;
82 	u32 sirfsoc_rxfifo_full;
83 	u32 sirfsoc_txfifo_empty;
84 	u32 sirfsoc_rxfifo_thd;
85 	u32 sirfsoc_txfifo_thd;
86 	u32 sirfsoc_frm_err;
87 	u32 sirfsoc_rxd_brk;
88 	u32 sirfsoc_rx_timeout;
89 	u32 sirfsoc_parity_err;
90 	u32 sirfsoc_cts;
91 	u32 sirfsoc_rts;
92 };
93 
94 enum sirfsoc_uart_type {
95 	SIRF_REAL_UART,
96 	SIRF_USP_UART,
97 };
98 
99 struct sirfsoc_uart_register {
100 	struct sirfsoc_register uart_reg;
101 	struct sirfsoc_int_en uart_int_en;
102 	struct sirfsoc_int_status uart_int_st;
103 	struct sirfsoc_fifo_status fifo_status;
104 	struct sirfsoc_uart_param uart_param;
105 	enum sirfsoc_uart_type uart_type;
106 };
107 
uart_usp_ff_full_mask(struct uart_port * port)108 static u32 uart_usp_ff_full_mask(struct uart_port *port)
109 {
110 	u32 full_bit;
111 
112 	full_bit = ilog2(port->fifosize);
113 	return (1 << full_bit);
114 }
115 
uart_usp_ff_empty_mask(struct uart_port * port)116 static u32 uart_usp_ff_empty_mask(struct uart_port *port)
117 {
118 	u32 empty_bit;
119 
120 	empty_bit = ilog2(port->fifosize) + 1;
121 	return (1 << empty_bit);
122 }
123 
124 static struct sirfsoc_uart_register sirfsoc_usp = {
125 	.uart_reg = {
126 		.sirfsoc_mode1		= 0x0000,
127 		.sirfsoc_mode2		= 0x0004,
128 		.sirfsoc_tx_frame_ctrl	= 0x0008,
129 		.sirfsoc_rx_frame_ctrl	= 0x000c,
130 		.sirfsoc_tx_rx_en	= 0x0010,
131 		.sirfsoc_int_en_reg	= 0x0014,
132 		.sirfsoc_int_st_reg	= 0x0018,
133 		.sirfsoc_async_param_reg = 0x0024,
134 		.sirfsoc_tx_dma_io_ctrl	= 0x0100,
135 		.sirfsoc_tx_dma_io_len	= 0x0104,
136 		.sirfsoc_tx_fifo_ctrl	= 0x0108,
137 		.sirfsoc_tx_fifo_level_chk = 0x010c,
138 		.sirfsoc_tx_fifo_op	= 0x0110,
139 		.sirfsoc_tx_fifo_status	= 0x0114,
140 		.sirfsoc_tx_fifo_data	= 0x0118,
141 		.sirfsoc_rx_dma_io_ctrl	= 0x0120,
142 		.sirfsoc_rx_dma_io_len	= 0x0124,
143 		.sirfsoc_rx_fifo_ctrl	= 0x0128,
144 		.sirfsoc_rx_fifo_level_chk = 0x012c,
145 		.sirfsoc_rx_fifo_op	= 0x0130,
146 		.sirfsoc_rx_fifo_status	= 0x0134,
147 		.sirfsoc_rx_fifo_data	= 0x0138,
148 		.sirfsoc_int_en_clr_reg = 0x140,
149 	},
150 	.uart_int_en = {
151 		.sirfsoc_rx_done_en	= BIT(0),
152 		.sirfsoc_tx_done_en	= BIT(1),
153 		.sirfsoc_rx_oflow_en	= BIT(2),
154 		.sirfsoc_tx_allout_en	= BIT(3),
155 		.sirfsoc_rx_io_dma_en	= BIT(4),
156 		.sirfsoc_tx_io_dma_en	= BIT(5),
157 		.sirfsoc_rxfifo_full_en	= BIT(6),
158 		.sirfsoc_txfifo_empty_en = BIT(7),
159 		.sirfsoc_rxfifo_thd_en	= BIT(8),
160 		.sirfsoc_txfifo_thd_en	= BIT(9),
161 		.sirfsoc_frm_err_en	= BIT(10),
162 		.sirfsoc_rx_timeout_en	= BIT(11),
163 		.sirfsoc_rxd_brk_en	= BIT(15),
164 	},
165 	.uart_int_st = {
166 		.sirfsoc_rx_done	= BIT(0),
167 		.sirfsoc_tx_done	= BIT(1),
168 		.sirfsoc_rx_oflow	= BIT(2),
169 		.sirfsoc_tx_allout	= BIT(3),
170 		.sirfsoc_rx_io_dma	= BIT(4),
171 		.sirfsoc_tx_io_dma	= BIT(5),
172 		.sirfsoc_rxfifo_full	= BIT(6),
173 		.sirfsoc_txfifo_empty	= BIT(7),
174 		.sirfsoc_rxfifo_thd	= BIT(8),
175 		.sirfsoc_txfifo_thd	= BIT(9),
176 		.sirfsoc_frm_err	= BIT(10),
177 		.sirfsoc_rx_timeout	= BIT(11),
178 		.sirfsoc_rxd_brk	= BIT(15),
179 	},
180 	.fifo_status = {
181 		.ff_full		= uart_usp_ff_full_mask,
182 		.ff_empty		= uart_usp_ff_empty_mask,
183 	},
184 	.uart_param = {
185 		.uart_name = "ttySiRF",
186 		.port_name = "sirfsoc-uart",
187 	},
188 };
189 
190 static struct sirfsoc_uart_register sirfsoc_uart = {
191 	.uart_reg = {
192 		.sirfsoc_line_ctrl	= 0x0040,
193 		.sirfsoc_tx_rx_en	= 0x004c,
194 		.sirfsoc_divisor	= 0x0050,
195 		.sirfsoc_int_en_reg	= 0x0054,
196 		.sirfsoc_int_st_reg	= 0x0058,
197 		.sirfsoc_int_en_clr_reg	= 0x0060,
198 		.sirfsoc_tx_dma_io_ctrl	= 0x0100,
199 		.sirfsoc_tx_dma_io_len	= 0x0104,
200 		.sirfsoc_tx_fifo_ctrl	= 0x0108,
201 		.sirfsoc_tx_fifo_level_chk = 0x010c,
202 		.sirfsoc_tx_fifo_op	= 0x0110,
203 		.sirfsoc_tx_fifo_status	= 0x0114,
204 		.sirfsoc_tx_fifo_data	= 0x0118,
205 		.sirfsoc_rx_dma_io_ctrl	= 0x0120,
206 		.sirfsoc_rx_dma_io_len	= 0x0124,
207 		.sirfsoc_rx_fifo_ctrl	= 0x0128,
208 		.sirfsoc_rx_fifo_level_chk = 0x012c,
209 		.sirfsoc_rx_fifo_op	= 0x0130,
210 		.sirfsoc_rx_fifo_status	= 0x0134,
211 		.sirfsoc_rx_fifo_data	= 0x0138,
212 		.sirfsoc_afc_ctrl	= 0x0140,
213 		.sirfsoc_swh_dma_io	= 0x0148,
214 	},
215 	.uart_int_en = {
216 		.sirfsoc_rx_done_en	= BIT(0),
217 		.sirfsoc_tx_done_en	= BIT(1),
218 		.sirfsoc_rx_oflow_en	= BIT(2),
219 		.sirfsoc_tx_allout_en	= BIT(3),
220 		.sirfsoc_rx_io_dma_en	= BIT(4),
221 		.sirfsoc_tx_io_dma_en	= BIT(5),
222 		.sirfsoc_rxfifo_full_en	= BIT(6),
223 		.sirfsoc_txfifo_empty_en = BIT(7),
224 		.sirfsoc_rxfifo_thd_en	= BIT(8),
225 		.sirfsoc_txfifo_thd_en	= BIT(9),
226 		.sirfsoc_frm_err_en	= BIT(10),
227 		.sirfsoc_rxd_brk_en	= BIT(11),
228 		.sirfsoc_rx_timeout_en	= BIT(12),
229 		.sirfsoc_parity_err_en	= BIT(13),
230 		.sirfsoc_cts_en		= BIT(14),
231 		.sirfsoc_rts_en		= BIT(15),
232 	},
233 	.uart_int_st = {
234 		.sirfsoc_rx_done	= BIT(0),
235 		.sirfsoc_tx_done	= BIT(1),
236 		.sirfsoc_rx_oflow	= BIT(2),
237 		.sirfsoc_tx_allout	= BIT(3),
238 		.sirfsoc_rx_io_dma	= BIT(4),
239 		.sirfsoc_tx_io_dma	= BIT(5),
240 		.sirfsoc_rxfifo_full	= BIT(6),
241 		.sirfsoc_txfifo_empty	= BIT(7),
242 		.sirfsoc_rxfifo_thd	= BIT(8),
243 		.sirfsoc_txfifo_thd	= BIT(9),
244 		.sirfsoc_frm_err	= BIT(10),
245 		.sirfsoc_rxd_brk	= BIT(11),
246 		.sirfsoc_rx_timeout	= BIT(12),
247 		.sirfsoc_parity_err	= BIT(13),
248 		.sirfsoc_cts		= BIT(14),
249 		.sirfsoc_rts		= BIT(15),
250 	},
251 	.fifo_status = {
252 		.ff_full		= uart_usp_ff_full_mask,
253 		.ff_empty		= uart_usp_ff_empty_mask,
254 	},
255 	.uart_param = {
256 		.uart_name = "ttySiRF",
257 		.port_name = "sirfsoc_uart",
258 	},
259 };
260 /* uart io ctrl */
261 #define SIRFUART_DATA_BIT_LEN_MASK		0x3
262 #define SIRFUART_DATA_BIT_LEN_5			BIT(0)
263 #define SIRFUART_DATA_BIT_LEN_6			1
264 #define SIRFUART_DATA_BIT_LEN_7			2
265 #define SIRFUART_DATA_BIT_LEN_8			3
266 #define SIRFUART_STOP_BIT_LEN_1			0
267 #define SIRFUART_STOP_BIT_LEN_2			BIT(2)
268 #define SIRFUART_PARITY_EN			BIT(3)
269 #define SIRFUART_EVEN_BIT			BIT(4)
270 #define SIRFUART_STICK_BIT_MASK			(7 << 3)
271 #define SIRFUART_STICK_BIT_NONE			(0 << 3)
272 #define SIRFUART_STICK_BIT_EVEN			BIT(3)
273 #define SIRFUART_STICK_BIT_ODD			(3 << 3)
274 #define SIRFUART_STICK_BIT_MARK			(5 << 3)
275 #define SIRFUART_STICK_BIT_SPACE		(7 << 3)
276 #define SIRFUART_SET_BREAK			BIT(6)
277 #define SIRFUART_LOOP_BACK			BIT(7)
278 #define SIRFUART_PARITY_MASK			(7 << 3)
279 #define SIRFUART_DUMMY_READ			BIT(16)
280 #define SIRFUART_AFC_CTRL_RX_THD		0x70
281 #define SIRFUART_AFC_RX_EN			BIT(8)
282 #define SIRFUART_AFC_TX_EN			BIT(9)
283 #define SIRFUART_AFC_CTS_CTRL			BIT(10)
284 #define SIRFUART_AFC_RTS_CTRL			BIT(11)
285 #define	SIRFUART_AFC_CTS_STATUS			BIT(12)
286 #define	SIRFUART_AFC_RTS_STATUS			BIT(13)
287 /* UART FIFO Register */
288 #define SIRFUART_FIFO_STOP			0x0
289 #define SIRFUART_FIFO_RESET			BIT(0)
290 #define SIRFUART_FIFO_START			BIT(1)
291 
292 #define SIRFUART_RX_EN				BIT(0)
293 #define SIRFUART_TX_EN				BIT(1)
294 
295 #define SIRFUART_IO_MODE			BIT(0)
296 #define SIRFUART_DMA_MODE			0x0
297 #define SIRFUART_RX_DMA_FLUSH			0x4
298 
299 #define SIRFUART_CLEAR_RX_ADDR_EN		0x2
300 /* Baud Rate Calculation */
301 #define SIRF_USP_MIN_SAMPLE_DIV			0x1
302 #define SIRF_MIN_SAMPLE_DIV			0xf
303 #define SIRF_MAX_SAMPLE_DIV			0x3f
304 #define SIRF_IOCLK_DIV_MAX			0xffff
305 #define SIRF_SAMPLE_DIV_SHIFT			16
306 #define SIRF_IOCLK_DIV_MASK			0xffff
307 #define SIRF_SAMPLE_DIV_MASK			0x3f0000
308 #define SIRF_BAUD_RATE_SUPPORT_NR		18
309 
310 /* USP SPEC */
311 #define SIRFSOC_USP_ENDIAN_CTRL_LSBF		BIT(4)
312 #define SIRFSOC_USP_EN				BIT(5)
313 #define SIRFSOC_USP_MODE2_RXD_DELAY_OFFSET	0
314 #define SIRFSOC_USP_MODE2_TXD_DELAY_OFFSET	8
315 #define SIRFSOC_USP_MODE2_CLK_DIVISOR_MASK	0x3ff
316 #define SIRFSOC_USP_MODE2_CLK_DIVISOR_OFFSET	21
317 #define SIRFSOC_USP_TX_DATA_LEN_OFFSET		0
318 #define SIRFSOC_USP_TX_SYNC_LEN_OFFSET		8
319 #define SIRFSOC_USP_TX_FRAME_LEN_OFFSET		16
320 #define SIRFSOC_USP_TX_SHIFTER_LEN_OFFSET	24
321 #define SIRFSOC_USP_TX_CLK_DIVISOR_OFFSET	30
322 #define SIRFSOC_USP_RX_DATA_LEN_OFFSET		0
323 #define SIRFSOC_USP_RX_FRAME_LEN_OFFSET		8
324 #define SIRFSOC_USP_RX_SHIFTER_LEN_OFFSET	16
325 #define SIRFSOC_USP_RX_CLK_DIVISOR_OFFSET	24
326 #define SIRFSOC_USP_ASYNC_DIV2_MASK		0x3f
327 #define SIRFSOC_USP_ASYNC_DIV2_OFFSET		16
328 #define SIRFSOC_USP_LOOP_BACK_CTRL		BIT(2)
329 #define SIRFSOC_USP_FRADDR_CLR_EN		BIT(1)
330 /* USP-UART Common */
331 #define SIRFSOC_UART_RX_TIMEOUT(br, to)	(((br) * (((to) + 999) / 1000)) / 1000)
332 #define SIRFUART_RECV_TIMEOUT_VALUE(x)	\
333 				(((x) > 0xFFFF) ? 0xFFFF : ((x) & 0xFFFF))
334 #define SIRFUART_USP_RECV_TIMEOUT(x)	(x & 0xFFFF)
335 #define SIRFUART_UART_RECV_TIMEOUT(x)	((x & 0xFFFF) << 16)
336 
337 #define SIRFUART_FIFO_THD(port)		(port->fifosize >> 1)
338 #define SIRFUART_ERR_INT_STAT(unit_st, uart_type)			\
339 				(uint_st->sirfsoc_rx_oflow |		\
340 				uint_st->sirfsoc_frm_err |		\
341 				uint_st->sirfsoc_rxd_brk |		\
342 				((uart_type != SIRF_REAL_UART) ? \
343 				 0 : uint_st->sirfsoc_parity_err))
344 #define SIRFUART_RX_IO_INT_EN(uint_en, uart_type)			\
345 				(uint_en->sirfsoc_rx_done_en |\
346 				 uint_en->sirfsoc_rxfifo_thd_en |\
347 				 uint_en->sirfsoc_rxfifo_full_en |\
348 				 uint_en->sirfsoc_frm_err_en |\
349 				 uint_en->sirfsoc_rx_oflow_en |\
350 				 uint_en->sirfsoc_rxd_brk_en |\
351 				((uart_type != SIRF_REAL_UART) ? \
352 				 0 : uint_en->sirfsoc_parity_err_en))
353 #define SIRFUART_RX_IO_INT_ST(uint_st)				\
354 				(uint_st->sirfsoc_rxfifo_thd |\
355 				 uint_st->sirfsoc_rxfifo_full|\
356 				 uint_st->sirfsoc_rx_done |\
357 				 uint_st->sirfsoc_rx_timeout)
358 #define SIRFUART_CTS_INT_ST(uint_st)	(uint_st->sirfsoc_cts)
359 #define SIRFUART_RX_DMA_INT_EN(uint_en, uart_type)		\
360 				(uint_en->sirfsoc_frm_err_en |\
361 				 uint_en->sirfsoc_rx_oflow_en |\
362 				 uint_en->sirfsoc_rxd_brk_en |\
363 				((uart_type != SIRF_REAL_UART) ? \
364 				 0 : uint_en->sirfsoc_parity_err_en))
365 /* Generic Definitions */
366 #define SIRFSOC_UART_NAME			"ttySiRF"
367 #define SIRFSOC_UART_MAJOR			0
368 #define SIRFSOC_UART_MINOR			0
369 #define SIRFUART_PORT_NAME			"sirfsoc-uart"
370 #define SIRFUART_MAP_SIZE			0x200
371 #define SIRFSOC_UART_NR				11
372 #define SIRFSOC_PORT_TYPE			0xa5
373 
374 /* Uart Common Use Macro*/
375 #define SIRFSOC_RX_DMA_BUF_SIZE		(1024 * 32)
376 #define BYTES_TO_ALIGN(dma_addr)	((unsigned long)(dma_addr) & 0x3)
377 /* Uart Fifo Level Chk */
378 #define SIRFUART_TX_FIFO_SC_OFFSET	0
379 #define SIRFUART_TX_FIFO_LC_OFFSET	10
380 #define SIRFUART_TX_FIFO_HC_OFFSET	20
381 #define SIRFUART_TX_FIFO_CHK_SC(line, value) ((((line) == 1) ? (value & 0x3) :\
382 				(value & 0x1f)) << SIRFUART_TX_FIFO_SC_OFFSET)
383 #define SIRFUART_TX_FIFO_CHK_LC(line, value) ((((line) == 1) ? (value & 0x3) :\
384 				(value & 0x1f)) << SIRFUART_TX_FIFO_LC_OFFSET)
385 #define SIRFUART_TX_FIFO_CHK_HC(line, value) ((((line) == 1) ? (value & 0x3) :\
386 				(value & 0x1f)) << SIRFUART_TX_FIFO_HC_OFFSET)
387 
388 #define SIRFUART_RX_FIFO_CHK_SC SIRFUART_TX_FIFO_CHK_SC
389 #define	SIRFUART_RX_FIFO_CHK_LC SIRFUART_TX_FIFO_CHK_LC
390 #define SIRFUART_RX_FIFO_CHK_HC SIRFUART_TX_FIFO_CHK_HC
391 #define SIRFUART_RX_FIFO_MASK 0x7f
392 /* Indicate how many buffers used */
393 
394 /* For Fast Baud Rate Calculation */
395 struct sirfsoc_baudrate_to_regv {
396 	unsigned int baud_rate;
397 	unsigned int reg_val;
398 };
399 
400 enum sirfsoc_tx_state {
401 	TX_DMA_IDLE,
402 	TX_DMA_RUNNING,
403 	TX_DMA_PAUSE,
404 };
405 
406 struct sirfsoc_rx_buffer {
407 	struct circ_buf			xmit;
408 	dma_cookie_t			cookie;
409 	struct dma_async_tx_descriptor	*desc;
410 	dma_addr_t			dma_addr;
411 };
412 
413 struct sirfsoc_uart_port {
414 	bool				hw_flow_ctrl;
415 	bool				ms_enabled;
416 
417 	struct uart_port		port;
418 	struct clk			*clk;
419 	/* for SiRFatlas7, there are SET/CLR for UART_INT_EN */
420 	bool				is_atlas7;
421 	struct sirfsoc_uart_register	*uart_reg;
422 	struct dma_chan			*rx_dma_chan;
423 	struct dma_chan			*tx_dma_chan;
424 	dma_addr_t			tx_dma_addr;
425 	struct dma_async_tx_descriptor	*tx_dma_desc;
426 	unsigned long			transfer_size;
427 	enum sirfsoc_tx_state		tx_dma_state;
428 	unsigned int			cts_gpio;
429 	unsigned int			rts_gpio;
430 
431 	struct sirfsoc_rx_buffer	rx_dma_items;
432 	struct hrtimer			hrt;
433 	bool				is_hrt_enabled;
434 	unsigned long			rx_period_time;
435 	unsigned long			rx_last_pos;
436 	unsigned long			pio_fetch_cnt;
437 };
438 
439 /* Register Access Control */
440 #define portaddr(port, reg)		((port)->membase + (reg))
441 #define rd_regl(port, reg)		(__raw_readl(portaddr(port, reg)))
442 #define wr_regl(port, reg, val)		__raw_writel(val, portaddr(port, reg))
443 
444 /* UART Port Mask */
445 #define SIRFUART_FIFOLEVEL_MASK(port)	((port->fifosize - 1) & 0xFFF)
446 #define SIRFUART_FIFOFULL_MASK(port)	(port->fifosize & 0xFFF)
447 #define SIRFUART_FIFOEMPTY_MASK(port)	((port->fifosize & 0xFFF) << 1)
448