xref: /openbmc/linux/drivers/tty/serial/pch_uart.c (revision 1a59d1b8)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
4  */
5 #if defined(CONFIG_SERIAL_PCH_UART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
6 #define SUPPORT_SYSRQ
7 #endif
8 #include <linux/kernel.h>
9 #include <linux/serial_reg.h>
10 #include <linux/slab.h>
11 #include <linux/module.h>
12 #include <linux/pci.h>
13 #include <linux/console.h>
14 #include <linux/serial_core.h>
15 #include <linux/tty.h>
16 #include <linux/tty_flip.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/dmi.h>
20 #include <linux/nmi.h>
21 #include <linux/delay.h>
22 #include <linux/of.h>
23 
24 #include <linux/debugfs.h>
25 #include <linux/dmaengine.h>
26 #include <linux/pch_dma.h>
27 
28 enum {
29 	PCH_UART_HANDLED_RX_INT_SHIFT,
30 	PCH_UART_HANDLED_TX_INT_SHIFT,
31 	PCH_UART_HANDLED_RX_ERR_INT_SHIFT,
32 	PCH_UART_HANDLED_RX_TRG_INT_SHIFT,
33 	PCH_UART_HANDLED_MS_INT_SHIFT,
34 	PCH_UART_HANDLED_LS_INT_SHIFT,
35 };
36 
37 #define PCH_UART_DRIVER_DEVICE "ttyPCH"
38 
39 /* Set the max number of UART port
40  * Intel EG20T PCH: 4 port
41  * LAPIS Semiconductor ML7213 IOH: 3 port
42  * LAPIS Semiconductor ML7223 IOH: 2 port
43 */
44 #define PCH_UART_NR	4
45 
46 #define PCH_UART_HANDLED_RX_INT	(1<<((PCH_UART_HANDLED_RX_INT_SHIFT)<<1))
47 #define PCH_UART_HANDLED_TX_INT	(1<<((PCH_UART_HANDLED_TX_INT_SHIFT)<<1))
48 #define PCH_UART_HANDLED_RX_ERR_INT	(1<<((\
49 					PCH_UART_HANDLED_RX_ERR_INT_SHIFT)<<1))
50 #define PCH_UART_HANDLED_RX_TRG_INT	(1<<((\
51 					PCH_UART_HANDLED_RX_TRG_INT_SHIFT)<<1))
52 #define PCH_UART_HANDLED_MS_INT	(1<<((PCH_UART_HANDLED_MS_INT_SHIFT)<<1))
53 
54 #define PCH_UART_HANDLED_LS_INT	(1<<((PCH_UART_HANDLED_LS_INT_SHIFT)<<1))
55 
56 #define PCH_UART_RBR		0x00
57 #define PCH_UART_THR		0x00
58 
59 #define PCH_UART_IER_MASK	(PCH_UART_IER_ERBFI|PCH_UART_IER_ETBEI|\
60 				PCH_UART_IER_ELSI|PCH_UART_IER_EDSSI)
61 #define PCH_UART_IER_ERBFI	0x00000001
62 #define PCH_UART_IER_ETBEI	0x00000002
63 #define PCH_UART_IER_ELSI	0x00000004
64 #define PCH_UART_IER_EDSSI	0x00000008
65 
66 #define PCH_UART_IIR_IP			0x00000001
67 #define PCH_UART_IIR_IID		0x00000006
68 #define PCH_UART_IIR_MSI		0x00000000
69 #define PCH_UART_IIR_TRI		0x00000002
70 #define PCH_UART_IIR_RRI		0x00000004
71 #define PCH_UART_IIR_REI		0x00000006
72 #define PCH_UART_IIR_TOI		0x00000008
73 #define PCH_UART_IIR_FIFO256		0x00000020
74 #define PCH_UART_IIR_FIFO64		PCH_UART_IIR_FIFO256
75 #define PCH_UART_IIR_FE			0x000000C0
76 
77 #define PCH_UART_FCR_FIFOE		0x00000001
78 #define PCH_UART_FCR_RFR		0x00000002
79 #define PCH_UART_FCR_TFR		0x00000004
80 #define PCH_UART_FCR_DMS		0x00000008
81 #define PCH_UART_FCR_FIFO256		0x00000020
82 #define PCH_UART_FCR_RFTL		0x000000C0
83 
84 #define PCH_UART_FCR_RFTL1		0x00000000
85 #define PCH_UART_FCR_RFTL64		0x00000040
86 #define PCH_UART_FCR_RFTL128		0x00000080
87 #define PCH_UART_FCR_RFTL224		0x000000C0
88 #define PCH_UART_FCR_RFTL16		PCH_UART_FCR_RFTL64
89 #define PCH_UART_FCR_RFTL32		PCH_UART_FCR_RFTL128
90 #define PCH_UART_FCR_RFTL56		PCH_UART_FCR_RFTL224
91 #define PCH_UART_FCR_RFTL4		PCH_UART_FCR_RFTL64
92 #define PCH_UART_FCR_RFTL8		PCH_UART_FCR_RFTL128
93 #define PCH_UART_FCR_RFTL14		PCH_UART_FCR_RFTL224
94 #define PCH_UART_FCR_RFTL_SHIFT		6
95 
96 #define PCH_UART_LCR_WLS	0x00000003
97 #define PCH_UART_LCR_STB	0x00000004
98 #define PCH_UART_LCR_PEN	0x00000008
99 #define PCH_UART_LCR_EPS	0x00000010
100 #define PCH_UART_LCR_SP		0x00000020
101 #define PCH_UART_LCR_SB		0x00000040
102 #define PCH_UART_LCR_DLAB	0x00000080
103 #define PCH_UART_LCR_NP		0x00000000
104 #define PCH_UART_LCR_OP		PCH_UART_LCR_PEN
105 #define PCH_UART_LCR_EP		(PCH_UART_LCR_PEN | PCH_UART_LCR_EPS)
106 #define PCH_UART_LCR_1P		(PCH_UART_LCR_PEN | PCH_UART_LCR_SP)
107 #define PCH_UART_LCR_0P		(PCH_UART_LCR_PEN | PCH_UART_LCR_EPS |\
108 				PCH_UART_LCR_SP)
109 
110 #define PCH_UART_LCR_5BIT	0x00000000
111 #define PCH_UART_LCR_6BIT	0x00000001
112 #define PCH_UART_LCR_7BIT	0x00000002
113 #define PCH_UART_LCR_8BIT	0x00000003
114 
115 #define PCH_UART_MCR_DTR	0x00000001
116 #define PCH_UART_MCR_RTS	0x00000002
117 #define PCH_UART_MCR_OUT	0x0000000C
118 #define PCH_UART_MCR_LOOP	0x00000010
119 #define PCH_UART_MCR_AFE	0x00000020
120 
121 #define PCH_UART_LSR_DR		0x00000001
122 #define PCH_UART_LSR_ERR	(1<<7)
123 
124 #define PCH_UART_MSR_DCTS	0x00000001
125 #define PCH_UART_MSR_DDSR	0x00000002
126 #define PCH_UART_MSR_TERI	0x00000004
127 #define PCH_UART_MSR_DDCD	0x00000008
128 #define PCH_UART_MSR_CTS	0x00000010
129 #define PCH_UART_MSR_DSR	0x00000020
130 #define PCH_UART_MSR_RI		0x00000040
131 #define PCH_UART_MSR_DCD	0x00000080
132 #define PCH_UART_MSR_DELTA	(PCH_UART_MSR_DCTS | PCH_UART_MSR_DDSR |\
133 				PCH_UART_MSR_TERI | PCH_UART_MSR_DDCD)
134 
135 #define PCH_UART_DLL		0x00
136 #define PCH_UART_DLM		0x01
137 
138 #define PCH_UART_BRCSR		0x0E
139 
140 #define PCH_UART_IID_RLS	(PCH_UART_IIR_REI)
141 #define PCH_UART_IID_RDR	(PCH_UART_IIR_RRI)
142 #define PCH_UART_IID_RDR_TO	(PCH_UART_IIR_RRI | PCH_UART_IIR_TOI)
143 #define PCH_UART_IID_THRE	(PCH_UART_IIR_TRI)
144 #define PCH_UART_IID_MS		(PCH_UART_IIR_MSI)
145 
146 #define PCH_UART_HAL_PARITY_NONE	(PCH_UART_LCR_NP)
147 #define PCH_UART_HAL_PARITY_ODD		(PCH_UART_LCR_OP)
148 #define PCH_UART_HAL_PARITY_EVEN	(PCH_UART_LCR_EP)
149 #define PCH_UART_HAL_PARITY_FIX1	(PCH_UART_LCR_1P)
150 #define PCH_UART_HAL_PARITY_FIX0	(PCH_UART_LCR_0P)
151 #define PCH_UART_HAL_5BIT		(PCH_UART_LCR_5BIT)
152 #define PCH_UART_HAL_6BIT		(PCH_UART_LCR_6BIT)
153 #define PCH_UART_HAL_7BIT		(PCH_UART_LCR_7BIT)
154 #define PCH_UART_HAL_8BIT		(PCH_UART_LCR_8BIT)
155 #define PCH_UART_HAL_STB1		0
156 #define PCH_UART_HAL_STB2		(PCH_UART_LCR_STB)
157 
158 #define PCH_UART_HAL_CLR_TX_FIFO	(PCH_UART_FCR_TFR)
159 #define PCH_UART_HAL_CLR_RX_FIFO	(PCH_UART_FCR_RFR)
160 #define PCH_UART_HAL_CLR_ALL_FIFO	(PCH_UART_HAL_CLR_TX_FIFO | \
161 					PCH_UART_HAL_CLR_RX_FIFO)
162 
163 #define PCH_UART_HAL_DMA_MODE0		0
164 #define PCH_UART_HAL_FIFO_DIS		0
165 #define PCH_UART_HAL_FIFO16		(PCH_UART_FCR_FIFOE)
166 #define PCH_UART_HAL_FIFO256		(PCH_UART_FCR_FIFOE | \
167 					PCH_UART_FCR_FIFO256)
168 #define PCH_UART_HAL_FIFO64		(PCH_UART_HAL_FIFO256)
169 #define PCH_UART_HAL_TRIGGER1		(PCH_UART_FCR_RFTL1)
170 #define PCH_UART_HAL_TRIGGER64		(PCH_UART_FCR_RFTL64)
171 #define PCH_UART_HAL_TRIGGER128		(PCH_UART_FCR_RFTL128)
172 #define PCH_UART_HAL_TRIGGER224		(PCH_UART_FCR_RFTL224)
173 #define PCH_UART_HAL_TRIGGER16		(PCH_UART_FCR_RFTL16)
174 #define PCH_UART_HAL_TRIGGER32		(PCH_UART_FCR_RFTL32)
175 #define PCH_UART_HAL_TRIGGER56		(PCH_UART_FCR_RFTL56)
176 #define PCH_UART_HAL_TRIGGER4		(PCH_UART_FCR_RFTL4)
177 #define PCH_UART_HAL_TRIGGER8		(PCH_UART_FCR_RFTL8)
178 #define PCH_UART_HAL_TRIGGER14		(PCH_UART_FCR_RFTL14)
179 #define PCH_UART_HAL_TRIGGER_L		(PCH_UART_FCR_RFTL64)
180 #define PCH_UART_HAL_TRIGGER_M		(PCH_UART_FCR_RFTL128)
181 #define PCH_UART_HAL_TRIGGER_H		(PCH_UART_FCR_RFTL224)
182 
183 #define PCH_UART_HAL_RX_INT		(PCH_UART_IER_ERBFI)
184 #define PCH_UART_HAL_TX_INT		(PCH_UART_IER_ETBEI)
185 #define PCH_UART_HAL_RX_ERR_INT		(PCH_UART_IER_ELSI)
186 #define PCH_UART_HAL_MS_INT		(PCH_UART_IER_EDSSI)
187 #define PCH_UART_HAL_ALL_INT		(PCH_UART_IER_MASK)
188 
189 #define PCH_UART_HAL_DTR		(PCH_UART_MCR_DTR)
190 #define PCH_UART_HAL_RTS		(PCH_UART_MCR_RTS)
191 #define PCH_UART_HAL_OUT		(PCH_UART_MCR_OUT)
192 #define PCH_UART_HAL_LOOP		(PCH_UART_MCR_LOOP)
193 #define PCH_UART_HAL_AFE		(PCH_UART_MCR_AFE)
194 
195 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
196 
197 #define DEFAULT_UARTCLK   1843200 /*   1.8432 MHz */
198 #define CMITC_UARTCLK   192000000 /* 192.0000 MHz */
199 #define FRI2_64_UARTCLK  64000000 /*  64.0000 MHz */
200 #define FRI2_48_UARTCLK  48000000 /*  48.0000 MHz */
201 #define NTC1_UARTCLK     64000000 /*  64.0000 MHz */
202 #define MINNOW_UARTCLK   50000000 /*  50.0000 MHz */
203 
204 struct pch_uart_buffer {
205 	unsigned char *buf;
206 	int size;
207 };
208 
209 struct eg20t_port {
210 	struct uart_port port;
211 	int port_type;
212 	void __iomem *membase;
213 	resource_size_t mapbase;
214 	unsigned int iobase;
215 	struct pci_dev *pdev;
216 	int fifo_size;
217 	unsigned int uartclk;
218 	int start_tx;
219 	int start_rx;
220 	int tx_empty;
221 	int trigger;
222 	int trigger_level;
223 	struct pch_uart_buffer rxbuf;
224 	unsigned int dmsr;
225 	unsigned int fcr;
226 	unsigned int mcr;
227 	unsigned int use_dma;
228 	struct dma_async_tx_descriptor	*desc_tx;
229 	struct dma_async_tx_descriptor	*desc_rx;
230 	struct pch_dma_slave		param_tx;
231 	struct pch_dma_slave		param_rx;
232 	struct dma_chan			*chan_tx;
233 	struct dma_chan			*chan_rx;
234 	struct scatterlist		*sg_tx_p;
235 	int				nent;
236 	struct scatterlist		sg_rx;
237 	int				tx_dma_use;
238 	void				*rx_buf_virt;
239 	dma_addr_t			rx_buf_dma;
240 
241 	struct dentry	*debugfs;
242 #define IRQ_NAME_SIZE 17
243 	char				irq_name[IRQ_NAME_SIZE];
244 
245 	/* protect the eg20t_port private structure and io access to membase */
246 	spinlock_t lock;
247 };
248 
249 /**
250  * struct pch_uart_driver_data - private data structure for UART-DMA
251  * @port_type:			The type of UART port
252  * @line_no:			UART port line number (0, 1, 2...)
253  */
254 struct pch_uart_driver_data {
255 	int port_type;
256 	int line_no;
257 };
258 
259 enum pch_uart_num_t {
260 	pch_et20t_uart0 = 0,
261 	pch_et20t_uart1,
262 	pch_et20t_uart2,
263 	pch_et20t_uart3,
264 	pch_ml7213_uart0,
265 	pch_ml7213_uart1,
266 	pch_ml7213_uart2,
267 	pch_ml7223_uart0,
268 	pch_ml7223_uart1,
269 	pch_ml7831_uart0,
270 	pch_ml7831_uart1,
271 };
272 
273 static struct pch_uart_driver_data drv_dat[] = {
274 	[pch_et20t_uart0] = {PORT_PCH_8LINE, 0},
275 	[pch_et20t_uart1] = {PORT_PCH_2LINE, 1},
276 	[pch_et20t_uart2] = {PORT_PCH_2LINE, 2},
277 	[pch_et20t_uart3] = {PORT_PCH_2LINE, 3},
278 	[pch_ml7213_uart0] = {PORT_PCH_8LINE, 0},
279 	[pch_ml7213_uart1] = {PORT_PCH_2LINE, 1},
280 	[pch_ml7213_uart2] = {PORT_PCH_2LINE, 2},
281 	[pch_ml7223_uart0] = {PORT_PCH_8LINE, 0},
282 	[pch_ml7223_uart1] = {PORT_PCH_2LINE, 1},
283 	[pch_ml7831_uart0] = {PORT_PCH_8LINE, 0},
284 	[pch_ml7831_uart1] = {PORT_PCH_2LINE, 1},
285 };
286 
287 #ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
288 static struct eg20t_port *pch_uart_ports[PCH_UART_NR];
289 #endif
290 static unsigned int default_baud = 9600;
291 static unsigned int user_uartclk = 0;
292 static const int trigger_level_256[4] = { 1, 64, 128, 224 };
293 static const int trigger_level_64[4] = { 1, 16, 32, 56 };
294 static const int trigger_level_16[4] = { 1, 4, 8, 14 };
295 static const int trigger_level_1[4] = { 1, 1, 1, 1 };
296 
297 #ifdef CONFIG_DEBUG_FS
298 
299 #define PCH_REGS_BUFSIZE	1024
300 
301 
302 static ssize_t port_show_regs(struct file *file, char __user *user_buf,
303 				size_t count, loff_t *ppos)
304 {
305 	struct eg20t_port *priv = file->private_data;
306 	char *buf;
307 	u32 len = 0;
308 	ssize_t ret;
309 	unsigned char lcr;
310 
311 	buf = kzalloc(PCH_REGS_BUFSIZE, GFP_KERNEL);
312 	if (!buf)
313 		return 0;
314 
315 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
316 			"PCH EG20T port[%d] regs:\n", priv->port.line);
317 
318 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
319 			"=================================\n");
320 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
321 			"IER: \t0x%02x\n", ioread8(priv->membase + UART_IER));
322 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
323 			"IIR: \t0x%02x\n", ioread8(priv->membase + UART_IIR));
324 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
325 			"LCR: \t0x%02x\n", ioread8(priv->membase + UART_LCR));
326 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
327 			"MCR: \t0x%02x\n", ioread8(priv->membase + UART_MCR));
328 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
329 			"LSR: \t0x%02x\n", ioread8(priv->membase + UART_LSR));
330 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
331 			"MSR: \t0x%02x\n", ioread8(priv->membase + UART_MSR));
332 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
333 			"BRCSR: \t0x%02x\n",
334 			ioread8(priv->membase + PCH_UART_BRCSR));
335 
336 	lcr = ioread8(priv->membase + UART_LCR);
337 	iowrite8(PCH_UART_LCR_DLAB, priv->membase + UART_LCR);
338 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
339 			"DLL: \t0x%02x\n", ioread8(priv->membase + UART_DLL));
340 	len += snprintf(buf + len, PCH_REGS_BUFSIZE - len,
341 			"DLM: \t0x%02x\n", ioread8(priv->membase + UART_DLM));
342 	iowrite8(lcr, priv->membase + UART_LCR);
343 
344 	if (len > PCH_REGS_BUFSIZE)
345 		len = PCH_REGS_BUFSIZE;
346 
347 	ret =  simple_read_from_buffer(user_buf, count, ppos, buf, len);
348 	kfree(buf);
349 	return ret;
350 }
351 
352 static const struct file_operations port_regs_ops = {
353 	.owner		= THIS_MODULE,
354 	.open		= simple_open,
355 	.read		= port_show_regs,
356 	.llseek		= default_llseek,
357 };
358 #endif	/* CONFIG_DEBUG_FS */
359 
360 static const struct dmi_system_id pch_uart_dmi_table[] = {
361 	{
362 		.ident = "CM-iTC",
363 		{
364 			DMI_MATCH(DMI_BOARD_NAME, "CM-iTC"),
365 		},
366 		(void *)CMITC_UARTCLK,
367 	},
368 	{
369 		.ident = "FRI2",
370 		{
371 			DMI_MATCH(DMI_BIOS_VERSION, "FRI2"),
372 		},
373 		(void *)FRI2_64_UARTCLK,
374 	},
375 	{
376 		.ident = "Fish River Island II",
377 		{
378 			DMI_MATCH(DMI_PRODUCT_NAME, "Fish River Island II"),
379 		},
380 		(void *)FRI2_48_UARTCLK,
381 	},
382 	{
383 		.ident = "COMe-mTT",
384 		{
385 			DMI_MATCH(DMI_BOARD_NAME, "COMe-mTT"),
386 		},
387 		(void *)NTC1_UARTCLK,
388 	},
389 	{
390 		.ident = "nanoETXexpress-TT",
391 		{
392 			DMI_MATCH(DMI_BOARD_NAME, "nanoETXexpress-TT"),
393 		},
394 		(void *)NTC1_UARTCLK,
395 	},
396 	{
397 		.ident = "MinnowBoard",
398 		{
399 			DMI_MATCH(DMI_BOARD_NAME, "MinnowBoard"),
400 		},
401 		(void *)MINNOW_UARTCLK,
402 	},
403 	{ }
404 };
405 
406 /* Return UART clock, checking for board specific clocks. */
407 static unsigned int pch_uart_get_uartclk(void)
408 {
409 	const struct dmi_system_id *d;
410 
411 	if (user_uartclk)
412 		return user_uartclk;
413 
414 	d = dmi_first_match(pch_uart_dmi_table);
415 	if (d)
416 		return (unsigned long)d->driver_data;
417 
418 	return DEFAULT_UARTCLK;
419 }
420 
421 static void pch_uart_hal_enable_interrupt(struct eg20t_port *priv,
422 					  unsigned int flag)
423 {
424 	u8 ier = ioread8(priv->membase + UART_IER);
425 	ier |= flag & PCH_UART_IER_MASK;
426 	iowrite8(ier, priv->membase + UART_IER);
427 }
428 
429 static void pch_uart_hal_disable_interrupt(struct eg20t_port *priv,
430 					   unsigned int flag)
431 {
432 	u8 ier = ioread8(priv->membase + UART_IER);
433 	ier &= ~(flag & PCH_UART_IER_MASK);
434 	iowrite8(ier, priv->membase + UART_IER);
435 }
436 
437 static int pch_uart_hal_set_line(struct eg20t_port *priv, unsigned int baud,
438 				 unsigned int parity, unsigned int bits,
439 				 unsigned int stb)
440 {
441 	unsigned int dll, dlm, lcr;
442 	int div;
443 
444 	div = DIV_ROUND_CLOSEST(priv->uartclk / 16, baud);
445 	if (div < 0 || USHRT_MAX <= div) {
446 		dev_err(priv->port.dev, "Invalid Baud(div=0x%x)\n", div);
447 		return -EINVAL;
448 	}
449 
450 	dll = (unsigned int)div & 0x00FFU;
451 	dlm = ((unsigned int)div >> 8) & 0x00FFU;
452 
453 	if (parity & ~(PCH_UART_LCR_PEN | PCH_UART_LCR_EPS | PCH_UART_LCR_SP)) {
454 		dev_err(priv->port.dev, "Invalid parity(0x%x)\n", parity);
455 		return -EINVAL;
456 	}
457 
458 	if (bits & ~PCH_UART_LCR_WLS) {
459 		dev_err(priv->port.dev, "Invalid bits(0x%x)\n", bits);
460 		return -EINVAL;
461 	}
462 
463 	if (stb & ~PCH_UART_LCR_STB) {
464 		dev_err(priv->port.dev, "Invalid STB(0x%x)\n", stb);
465 		return -EINVAL;
466 	}
467 
468 	lcr = parity;
469 	lcr |= bits;
470 	lcr |= stb;
471 
472 	dev_dbg(priv->port.dev, "%s:baud = %u, div = %04x, lcr = %02x (%lu)\n",
473 		 __func__, baud, div, lcr, jiffies);
474 	iowrite8(PCH_UART_LCR_DLAB, priv->membase + UART_LCR);
475 	iowrite8(dll, priv->membase + PCH_UART_DLL);
476 	iowrite8(dlm, priv->membase + PCH_UART_DLM);
477 	iowrite8(lcr, priv->membase + UART_LCR);
478 
479 	return 0;
480 }
481 
482 static int pch_uart_hal_fifo_reset(struct eg20t_port *priv,
483 				    unsigned int flag)
484 {
485 	if (flag & ~(PCH_UART_FCR_TFR | PCH_UART_FCR_RFR)) {
486 		dev_err(priv->port.dev, "%s:Invalid flag(0x%x)\n",
487 			__func__, flag);
488 		return -EINVAL;
489 	}
490 
491 	iowrite8(PCH_UART_FCR_FIFOE | priv->fcr, priv->membase + UART_FCR);
492 	iowrite8(PCH_UART_FCR_FIFOE | priv->fcr | flag,
493 		 priv->membase + UART_FCR);
494 	iowrite8(priv->fcr, priv->membase + UART_FCR);
495 
496 	return 0;
497 }
498 
499 static int pch_uart_hal_set_fifo(struct eg20t_port *priv,
500 				 unsigned int dmamode,
501 				 unsigned int fifo_size, unsigned int trigger)
502 {
503 	u8 fcr;
504 
505 	if (dmamode & ~PCH_UART_FCR_DMS) {
506 		dev_err(priv->port.dev, "%s:Invalid DMA Mode(0x%x)\n",
507 			__func__, dmamode);
508 		return -EINVAL;
509 	}
510 
511 	if (fifo_size & ~(PCH_UART_FCR_FIFOE | PCH_UART_FCR_FIFO256)) {
512 		dev_err(priv->port.dev, "%s:Invalid FIFO SIZE(0x%x)\n",
513 			__func__, fifo_size);
514 		return -EINVAL;
515 	}
516 
517 	if (trigger & ~PCH_UART_FCR_RFTL) {
518 		dev_err(priv->port.dev, "%s:Invalid TRIGGER(0x%x)\n",
519 			__func__, trigger);
520 		return -EINVAL;
521 	}
522 
523 	switch (priv->fifo_size) {
524 	case 256:
525 		priv->trigger_level =
526 		    trigger_level_256[trigger >> PCH_UART_FCR_RFTL_SHIFT];
527 		break;
528 	case 64:
529 		priv->trigger_level =
530 		    trigger_level_64[trigger >> PCH_UART_FCR_RFTL_SHIFT];
531 		break;
532 	case 16:
533 		priv->trigger_level =
534 		    trigger_level_16[trigger >> PCH_UART_FCR_RFTL_SHIFT];
535 		break;
536 	default:
537 		priv->trigger_level =
538 		    trigger_level_1[trigger >> PCH_UART_FCR_RFTL_SHIFT];
539 		break;
540 	}
541 	fcr =
542 	    dmamode | fifo_size | trigger | PCH_UART_FCR_RFR | PCH_UART_FCR_TFR;
543 	iowrite8(PCH_UART_FCR_FIFOE, priv->membase + UART_FCR);
544 	iowrite8(PCH_UART_FCR_FIFOE | PCH_UART_FCR_RFR | PCH_UART_FCR_TFR,
545 		 priv->membase + UART_FCR);
546 	iowrite8(fcr, priv->membase + UART_FCR);
547 	priv->fcr = fcr;
548 
549 	return 0;
550 }
551 
552 static u8 pch_uart_hal_get_modem(struct eg20t_port *priv)
553 {
554 	unsigned int msr = ioread8(priv->membase + UART_MSR);
555 	priv->dmsr = msr & PCH_UART_MSR_DELTA;
556 	return (u8)msr;
557 }
558 
559 static void pch_uart_hal_write(struct eg20t_port *priv,
560 			      const unsigned char *buf, int tx_size)
561 {
562 	int i;
563 	unsigned int thr;
564 
565 	for (i = 0; i < tx_size;) {
566 		thr = buf[i++];
567 		iowrite8(thr, priv->membase + PCH_UART_THR);
568 	}
569 }
570 
571 static int pch_uart_hal_read(struct eg20t_port *priv, unsigned char *buf,
572 			     int rx_size)
573 {
574 	int i;
575 	u8 rbr, lsr;
576 	struct uart_port *port = &priv->port;
577 
578 	lsr = ioread8(priv->membase + UART_LSR);
579 	for (i = 0, lsr = ioread8(priv->membase + UART_LSR);
580 	     i < rx_size && lsr & (UART_LSR_DR | UART_LSR_BI);
581 	     lsr = ioread8(priv->membase + UART_LSR)) {
582 		rbr = ioread8(priv->membase + PCH_UART_RBR);
583 
584 		if (lsr & UART_LSR_BI) {
585 			port->icount.brk++;
586 			if (uart_handle_break(port))
587 				continue;
588 		}
589 #ifdef SUPPORT_SYSRQ
590 		if (port->sysrq) {
591 			if (uart_handle_sysrq_char(port, rbr))
592 				continue;
593 		}
594 #endif
595 
596 		buf[i++] = rbr;
597 	}
598 	return i;
599 }
600 
601 static unsigned char pch_uart_hal_get_iid(struct eg20t_port *priv)
602 {
603 	return ioread8(priv->membase + UART_IIR) &\
604 		      (PCH_UART_IIR_IID | PCH_UART_IIR_TOI | PCH_UART_IIR_IP);
605 }
606 
607 static u8 pch_uart_hal_get_line_status(struct eg20t_port *priv)
608 {
609 	return ioread8(priv->membase + UART_LSR);
610 }
611 
612 static void pch_uart_hal_set_break(struct eg20t_port *priv, int on)
613 {
614 	unsigned int lcr;
615 
616 	lcr = ioread8(priv->membase + UART_LCR);
617 	if (on)
618 		lcr |= PCH_UART_LCR_SB;
619 	else
620 		lcr &= ~PCH_UART_LCR_SB;
621 
622 	iowrite8(lcr, priv->membase + UART_LCR);
623 }
624 
625 static int push_rx(struct eg20t_port *priv, const unsigned char *buf,
626 		   int size)
627 {
628 	struct uart_port *port = &priv->port;
629 	struct tty_port *tport = &port->state->port;
630 
631 	tty_insert_flip_string(tport, buf, size);
632 	tty_flip_buffer_push(tport);
633 
634 	return 0;
635 }
636 
637 static int pop_tx_x(struct eg20t_port *priv, unsigned char *buf)
638 {
639 	int ret = 0;
640 	struct uart_port *port = &priv->port;
641 
642 	if (port->x_char) {
643 		dev_dbg(priv->port.dev, "%s:X character send %02x (%lu)\n",
644 			__func__, port->x_char, jiffies);
645 		buf[0] = port->x_char;
646 		port->x_char = 0;
647 		ret = 1;
648 	}
649 
650 	return ret;
651 }
652 
653 static int dma_push_rx(struct eg20t_port *priv, int size)
654 {
655 	int room;
656 	struct uart_port *port = &priv->port;
657 	struct tty_port *tport = &port->state->port;
658 
659 	room = tty_buffer_request_room(tport, size);
660 
661 	if (room < size)
662 		dev_warn(port->dev, "Rx overrun: dropping %u bytes\n",
663 			 size - room);
664 	if (!room)
665 		return 0;
666 
667 	tty_insert_flip_string(tport, sg_virt(&priv->sg_rx), size);
668 
669 	port->icount.rx += room;
670 
671 	return room;
672 }
673 
674 static void pch_free_dma(struct uart_port *port)
675 {
676 	struct eg20t_port *priv;
677 	priv = container_of(port, struct eg20t_port, port);
678 
679 	if (priv->chan_tx) {
680 		dma_release_channel(priv->chan_tx);
681 		priv->chan_tx = NULL;
682 	}
683 	if (priv->chan_rx) {
684 		dma_release_channel(priv->chan_rx);
685 		priv->chan_rx = NULL;
686 	}
687 
688 	if (priv->rx_buf_dma) {
689 		dma_free_coherent(port->dev, port->fifosize, priv->rx_buf_virt,
690 				  priv->rx_buf_dma);
691 		priv->rx_buf_virt = NULL;
692 		priv->rx_buf_dma = 0;
693 	}
694 
695 	return;
696 }
697 
698 static bool filter(struct dma_chan *chan, void *slave)
699 {
700 	struct pch_dma_slave *param = slave;
701 
702 	if ((chan->chan_id == param->chan_id) && (param->dma_dev ==
703 						  chan->device->dev)) {
704 		chan->private = param;
705 		return true;
706 	} else {
707 		return false;
708 	}
709 }
710 
711 static void pch_request_dma(struct uart_port *port)
712 {
713 	dma_cap_mask_t mask;
714 	struct dma_chan *chan;
715 	struct pci_dev *dma_dev;
716 	struct pch_dma_slave *param;
717 	struct eg20t_port *priv =
718 				container_of(port, struct eg20t_port, port);
719 	dma_cap_zero(mask);
720 	dma_cap_set(DMA_SLAVE, mask);
721 
722 	/* Get DMA's dev information */
723 	dma_dev = pci_get_slot(priv->pdev->bus,
724 			PCI_DEVFN(PCI_SLOT(priv->pdev->devfn), 0));
725 
726 	/* Set Tx DMA */
727 	param = &priv->param_tx;
728 	param->dma_dev = &dma_dev->dev;
729 	param->chan_id = priv->port.line * 2; /* Tx = 0, 2, 4, ... */
730 
731 	param->tx_reg = port->mapbase + UART_TX;
732 	chan = dma_request_channel(mask, filter, param);
733 	if (!chan) {
734 		dev_err(priv->port.dev, "%s:dma_request_channel FAILS(Tx)\n",
735 			__func__);
736 		return;
737 	}
738 	priv->chan_tx = chan;
739 
740 	/* Set Rx DMA */
741 	param = &priv->param_rx;
742 	param->dma_dev = &dma_dev->dev;
743 	param->chan_id = priv->port.line * 2 + 1; /* Rx = Tx + 1 */
744 
745 	param->rx_reg = port->mapbase + UART_RX;
746 	chan = dma_request_channel(mask, filter, param);
747 	if (!chan) {
748 		dev_err(priv->port.dev, "%s:dma_request_channel FAILS(Rx)\n",
749 			__func__);
750 		dma_release_channel(priv->chan_tx);
751 		priv->chan_tx = NULL;
752 		return;
753 	}
754 
755 	/* Get Consistent memory for DMA */
756 	priv->rx_buf_virt = dma_alloc_coherent(port->dev, port->fifosize,
757 				    &priv->rx_buf_dma, GFP_KERNEL);
758 	priv->chan_rx = chan;
759 }
760 
761 static void pch_dma_rx_complete(void *arg)
762 {
763 	struct eg20t_port *priv = arg;
764 	struct uart_port *port = &priv->port;
765 	int count;
766 
767 	dma_sync_sg_for_cpu(port->dev, &priv->sg_rx, 1, DMA_FROM_DEVICE);
768 	count = dma_push_rx(priv, priv->trigger_level);
769 	if (count)
770 		tty_flip_buffer_push(&port->state->port);
771 	async_tx_ack(priv->desc_rx);
772 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT |
773 					    PCH_UART_HAL_RX_ERR_INT);
774 }
775 
776 static void pch_dma_tx_complete(void *arg)
777 {
778 	struct eg20t_port *priv = arg;
779 	struct uart_port *port = &priv->port;
780 	struct circ_buf *xmit = &port->state->xmit;
781 	struct scatterlist *sg = priv->sg_tx_p;
782 	int i;
783 
784 	for (i = 0; i < priv->nent; i++, sg++) {
785 		xmit->tail += sg_dma_len(sg);
786 		port->icount.tx += sg_dma_len(sg);
787 	}
788 	xmit->tail &= UART_XMIT_SIZE - 1;
789 	async_tx_ack(priv->desc_tx);
790 	dma_unmap_sg(port->dev, sg, priv->nent, DMA_TO_DEVICE);
791 	priv->tx_dma_use = 0;
792 	priv->nent = 0;
793 	kfree(priv->sg_tx_p);
794 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_TX_INT);
795 }
796 
797 static int pop_tx(struct eg20t_port *priv, int size)
798 {
799 	int count = 0;
800 	struct uart_port *port = &priv->port;
801 	struct circ_buf *xmit = &port->state->xmit;
802 
803 	if (uart_tx_stopped(port) || uart_circ_empty(xmit) || count >= size)
804 		goto pop_tx_end;
805 
806 	do {
807 		int cnt_to_end =
808 		    CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
809 		int sz = min(size - count, cnt_to_end);
810 		pch_uart_hal_write(priv, &xmit->buf[xmit->tail], sz);
811 		xmit->tail = (xmit->tail + sz) & (UART_XMIT_SIZE - 1);
812 		count += sz;
813 	} while (!uart_circ_empty(xmit) && count < size);
814 
815 pop_tx_end:
816 	dev_dbg(priv->port.dev, "%d characters. Remained %d characters.(%lu)\n",
817 		 count, size - count, jiffies);
818 
819 	return count;
820 }
821 
822 static int handle_rx_to(struct eg20t_port *priv)
823 {
824 	struct pch_uart_buffer *buf;
825 	int rx_size;
826 	int ret;
827 	if (!priv->start_rx) {
828 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT |
829 						     PCH_UART_HAL_RX_ERR_INT);
830 		return 0;
831 	}
832 	buf = &priv->rxbuf;
833 	do {
834 		rx_size = pch_uart_hal_read(priv, buf->buf, buf->size);
835 		ret = push_rx(priv, buf->buf, rx_size);
836 		if (ret)
837 			return 0;
838 	} while (rx_size == buf->size);
839 
840 	return PCH_UART_HANDLED_RX_INT;
841 }
842 
843 static int handle_rx(struct eg20t_port *priv)
844 {
845 	return handle_rx_to(priv);
846 }
847 
848 static int dma_handle_rx(struct eg20t_port *priv)
849 {
850 	struct uart_port *port = &priv->port;
851 	struct dma_async_tx_descriptor *desc;
852 	struct scatterlist *sg;
853 
854 	priv = container_of(port, struct eg20t_port, port);
855 	sg = &priv->sg_rx;
856 
857 	sg_init_table(&priv->sg_rx, 1); /* Initialize SG table */
858 
859 	sg_dma_len(sg) = priv->trigger_level;
860 
861 	sg_set_page(&priv->sg_rx, virt_to_page(priv->rx_buf_virt),
862 		     sg_dma_len(sg), offset_in_page(priv->rx_buf_virt));
863 
864 	sg_dma_address(sg) = priv->rx_buf_dma;
865 
866 	desc = dmaengine_prep_slave_sg(priv->chan_rx,
867 			sg, 1, DMA_DEV_TO_MEM,
868 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
869 
870 	if (!desc)
871 		return 0;
872 
873 	priv->desc_rx = desc;
874 	desc->callback = pch_dma_rx_complete;
875 	desc->callback_param = priv;
876 	desc->tx_submit(desc);
877 	dma_async_issue_pending(priv->chan_rx);
878 
879 	return PCH_UART_HANDLED_RX_INT;
880 }
881 
882 static unsigned int handle_tx(struct eg20t_port *priv)
883 {
884 	struct uart_port *port = &priv->port;
885 	struct circ_buf *xmit = &port->state->xmit;
886 	int fifo_size;
887 	int tx_size;
888 	int size;
889 	int tx_empty;
890 
891 	if (!priv->start_tx) {
892 		dev_info(priv->port.dev, "%s:Tx isn't started. (%lu)\n",
893 			__func__, jiffies);
894 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
895 		priv->tx_empty = 1;
896 		return 0;
897 	}
898 
899 	fifo_size = max(priv->fifo_size, 1);
900 	tx_empty = 1;
901 	if (pop_tx_x(priv, xmit->buf)) {
902 		pch_uart_hal_write(priv, xmit->buf, 1);
903 		port->icount.tx++;
904 		tx_empty = 0;
905 		fifo_size--;
906 	}
907 	size = min(xmit->head - xmit->tail, fifo_size);
908 	if (size < 0)
909 		size = fifo_size;
910 
911 	tx_size = pop_tx(priv, size);
912 	if (tx_size > 0) {
913 		port->icount.tx += tx_size;
914 		tx_empty = 0;
915 	}
916 
917 	priv->tx_empty = tx_empty;
918 
919 	if (tx_empty) {
920 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
921 		uart_write_wakeup(port);
922 	}
923 
924 	return PCH_UART_HANDLED_TX_INT;
925 }
926 
927 static unsigned int dma_handle_tx(struct eg20t_port *priv)
928 {
929 	struct uart_port *port = &priv->port;
930 	struct circ_buf *xmit = &port->state->xmit;
931 	struct scatterlist *sg;
932 	int nent;
933 	int fifo_size;
934 	struct dma_async_tx_descriptor *desc;
935 	int num;
936 	int i;
937 	int bytes;
938 	int size;
939 	int rem;
940 
941 	if (!priv->start_tx) {
942 		dev_info(priv->port.dev, "%s:Tx isn't started. (%lu)\n",
943 			__func__, jiffies);
944 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
945 		priv->tx_empty = 1;
946 		return 0;
947 	}
948 
949 	if (priv->tx_dma_use) {
950 		dev_dbg(priv->port.dev, "%s:Tx is not completed. (%lu)\n",
951 			__func__, jiffies);
952 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
953 		priv->tx_empty = 1;
954 		return 0;
955 	}
956 
957 	fifo_size = max(priv->fifo_size, 1);
958 	if (pop_tx_x(priv, xmit->buf)) {
959 		pch_uart_hal_write(priv, xmit->buf, 1);
960 		port->icount.tx++;
961 		fifo_size--;
962 	}
963 
964 	bytes = min((int)CIRC_CNT(xmit->head, xmit->tail,
965 			     UART_XMIT_SIZE), CIRC_CNT_TO_END(xmit->head,
966 			     xmit->tail, UART_XMIT_SIZE));
967 	if (!bytes) {
968 		dev_dbg(priv->port.dev, "%s 0 bytes return\n", __func__);
969 		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_TX_INT);
970 		uart_write_wakeup(port);
971 		return 0;
972 	}
973 
974 	if (bytes > fifo_size) {
975 		num = bytes / fifo_size + 1;
976 		size = fifo_size;
977 		rem = bytes % fifo_size;
978 	} else {
979 		num = 1;
980 		size = bytes;
981 		rem = bytes;
982 	}
983 
984 	dev_dbg(priv->port.dev, "%s num=%d size=%d rem=%d\n",
985 		__func__, num, size, rem);
986 
987 	priv->tx_dma_use = 1;
988 
989 	priv->sg_tx_p = kcalloc(num, sizeof(struct scatterlist), GFP_ATOMIC);
990 	if (!priv->sg_tx_p) {
991 		dev_err(priv->port.dev, "%s:kzalloc Failed\n", __func__);
992 		return 0;
993 	}
994 
995 	sg_init_table(priv->sg_tx_p, num); /* Initialize SG table */
996 	sg = priv->sg_tx_p;
997 
998 	for (i = 0; i < num; i++, sg++) {
999 		if (i == (num - 1))
1000 			sg_set_page(sg, virt_to_page(xmit->buf),
1001 				    rem, fifo_size * i);
1002 		else
1003 			sg_set_page(sg, virt_to_page(xmit->buf),
1004 				    size, fifo_size * i);
1005 	}
1006 
1007 	sg = priv->sg_tx_p;
1008 	nent = dma_map_sg(port->dev, sg, num, DMA_TO_DEVICE);
1009 	if (!nent) {
1010 		dev_err(priv->port.dev, "%s:dma_map_sg Failed\n", __func__);
1011 		return 0;
1012 	}
1013 	priv->nent = nent;
1014 
1015 	for (i = 0; i < nent; i++, sg++) {
1016 		sg->offset = (xmit->tail & (UART_XMIT_SIZE - 1)) +
1017 			      fifo_size * i;
1018 		sg_dma_address(sg) = (sg_dma_address(sg) &
1019 				    ~(UART_XMIT_SIZE - 1)) + sg->offset;
1020 		if (i == (nent - 1))
1021 			sg_dma_len(sg) = rem;
1022 		else
1023 			sg_dma_len(sg) = size;
1024 	}
1025 
1026 	desc = dmaengine_prep_slave_sg(priv->chan_tx,
1027 					priv->sg_tx_p, nent, DMA_MEM_TO_DEV,
1028 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1029 	if (!desc) {
1030 		dev_err(priv->port.dev, "%s:dmaengine_prep_slave_sg Failed\n",
1031 			__func__);
1032 		return 0;
1033 	}
1034 	dma_sync_sg_for_device(port->dev, priv->sg_tx_p, nent, DMA_TO_DEVICE);
1035 	priv->desc_tx = desc;
1036 	desc->callback = pch_dma_tx_complete;
1037 	desc->callback_param = priv;
1038 
1039 	desc->tx_submit(desc);
1040 
1041 	dma_async_issue_pending(priv->chan_tx);
1042 
1043 	return PCH_UART_HANDLED_TX_INT;
1044 }
1045 
1046 static void pch_uart_err_ir(struct eg20t_port *priv, unsigned int lsr)
1047 {
1048 	struct uart_port *port = &priv->port;
1049 	struct tty_struct *tty = tty_port_tty_get(&port->state->port);
1050 	char   *error_msg[5] = {};
1051 	int    i = 0;
1052 
1053 	if (lsr & PCH_UART_LSR_ERR)
1054 		error_msg[i++] = "Error data in FIFO\n";
1055 
1056 	if (lsr & UART_LSR_FE) {
1057 		port->icount.frame++;
1058 		error_msg[i++] = "  Framing Error\n";
1059 	}
1060 
1061 	if (lsr & UART_LSR_PE) {
1062 		port->icount.parity++;
1063 		error_msg[i++] = "  Parity Error\n";
1064 	}
1065 
1066 	if (lsr & UART_LSR_OE) {
1067 		port->icount.overrun++;
1068 		error_msg[i++] = "  Overrun Error\n";
1069 	}
1070 
1071 	if (tty == NULL) {
1072 		for (i = 0; error_msg[i] != NULL; i++)
1073 			dev_err(&priv->pdev->dev, error_msg[i]);
1074 	} else {
1075 		tty_kref_put(tty);
1076 	}
1077 }
1078 
1079 static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)
1080 {
1081 	struct eg20t_port *priv = dev_id;
1082 	unsigned int handled;
1083 	u8 lsr;
1084 	int ret = 0;
1085 	unsigned char iid;
1086 	unsigned long flags;
1087 	int next = 1;
1088 	u8 msr;
1089 
1090 	spin_lock_irqsave(&priv->lock, flags);
1091 	handled = 0;
1092 	while (next) {
1093 		iid = pch_uart_hal_get_iid(priv);
1094 		if (iid & PCH_UART_IIR_IP) /* No Interrupt */
1095 			break;
1096 		switch (iid) {
1097 		case PCH_UART_IID_RLS:	/* Receiver Line Status */
1098 			lsr = pch_uart_hal_get_line_status(priv);
1099 			if (lsr & (PCH_UART_LSR_ERR | UART_LSR_FE |
1100 						UART_LSR_PE | UART_LSR_OE)) {
1101 				pch_uart_err_ir(priv, lsr);
1102 				ret = PCH_UART_HANDLED_RX_ERR_INT;
1103 			} else {
1104 				ret = PCH_UART_HANDLED_LS_INT;
1105 			}
1106 			break;
1107 		case PCH_UART_IID_RDR:	/* Received Data Ready */
1108 			if (priv->use_dma) {
1109 				pch_uart_hal_disable_interrupt(priv,
1110 						PCH_UART_HAL_RX_INT |
1111 						PCH_UART_HAL_RX_ERR_INT);
1112 				ret = dma_handle_rx(priv);
1113 				if (!ret)
1114 					pch_uart_hal_enable_interrupt(priv,
1115 						PCH_UART_HAL_RX_INT |
1116 						PCH_UART_HAL_RX_ERR_INT);
1117 			} else {
1118 				ret = handle_rx(priv);
1119 			}
1120 			break;
1121 		case PCH_UART_IID_RDR_TO:	/* Received Data Ready
1122 						   (FIFO Timeout) */
1123 			ret = handle_rx_to(priv);
1124 			break;
1125 		case PCH_UART_IID_THRE:	/* Transmitter Holding Register
1126 						   Empty */
1127 			if (priv->use_dma)
1128 				ret = dma_handle_tx(priv);
1129 			else
1130 				ret = handle_tx(priv);
1131 			break;
1132 		case PCH_UART_IID_MS:	/* Modem Status */
1133 			msr = pch_uart_hal_get_modem(priv);
1134 			next = 0; /* MS ir prioirty is the lowest. So, MS ir
1135 				     means final interrupt */
1136 			if ((msr & UART_MSR_ANY_DELTA) == 0)
1137 				break;
1138 			ret |= PCH_UART_HANDLED_MS_INT;
1139 			break;
1140 		default:	/* Never junp to this label */
1141 			dev_err(priv->port.dev, "%s:iid=%02x (%lu)\n", __func__,
1142 				iid, jiffies);
1143 			ret = -1;
1144 			next = 0;
1145 			break;
1146 		}
1147 		handled |= (unsigned int)ret;
1148 	}
1149 
1150 	spin_unlock_irqrestore(&priv->lock, flags);
1151 	return IRQ_RETVAL(handled);
1152 }
1153 
1154 /* This function tests whether the transmitter fifo and shifter for the port
1155 						described by 'port' is empty. */
1156 static unsigned int pch_uart_tx_empty(struct uart_port *port)
1157 {
1158 	struct eg20t_port *priv;
1159 
1160 	priv = container_of(port, struct eg20t_port, port);
1161 	if (priv->tx_empty)
1162 		return TIOCSER_TEMT;
1163 	else
1164 		return 0;
1165 }
1166 
1167 /* Returns the current state of modem control inputs. */
1168 static unsigned int pch_uart_get_mctrl(struct uart_port *port)
1169 {
1170 	struct eg20t_port *priv;
1171 	u8 modem;
1172 	unsigned int ret = 0;
1173 
1174 	priv = container_of(port, struct eg20t_port, port);
1175 	modem = pch_uart_hal_get_modem(priv);
1176 
1177 	if (modem & UART_MSR_DCD)
1178 		ret |= TIOCM_CAR;
1179 
1180 	if (modem & UART_MSR_RI)
1181 		ret |= TIOCM_RNG;
1182 
1183 	if (modem & UART_MSR_DSR)
1184 		ret |= TIOCM_DSR;
1185 
1186 	if (modem & UART_MSR_CTS)
1187 		ret |= TIOCM_CTS;
1188 
1189 	return ret;
1190 }
1191 
1192 static void pch_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1193 {
1194 	u32 mcr = 0;
1195 	struct eg20t_port *priv = container_of(port, struct eg20t_port, port);
1196 
1197 	if (mctrl & TIOCM_DTR)
1198 		mcr |= UART_MCR_DTR;
1199 	if (mctrl & TIOCM_RTS)
1200 		mcr |= UART_MCR_RTS;
1201 	if (mctrl & TIOCM_LOOP)
1202 		mcr |= UART_MCR_LOOP;
1203 
1204 	if (priv->mcr & UART_MCR_AFE)
1205 		mcr |= UART_MCR_AFE;
1206 
1207 	if (mctrl)
1208 		iowrite8(mcr, priv->membase + UART_MCR);
1209 }
1210 
1211 static void pch_uart_stop_tx(struct uart_port *port)
1212 {
1213 	struct eg20t_port *priv;
1214 	priv = container_of(port, struct eg20t_port, port);
1215 	priv->start_tx = 0;
1216 	priv->tx_dma_use = 0;
1217 }
1218 
1219 static void pch_uart_start_tx(struct uart_port *port)
1220 {
1221 	struct eg20t_port *priv;
1222 
1223 	priv = container_of(port, struct eg20t_port, port);
1224 
1225 	if (priv->use_dma) {
1226 		if (priv->tx_dma_use) {
1227 			dev_dbg(priv->port.dev, "%s : Tx DMA is NOT empty.\n",
1228 				__func__);
1229 			return;
1230 		}
1231 	}
1232 
1233 	priv->start_tx = 1;
1234 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_TX_INT);
1235 }
1236 
1237 static void pch_uart_stop_rx(struct uart_port *port)
1238 {
1239 	struct eg20t_port *priv;
1240 	priv = container_of(port, struct eg20t_port, port);
1241 	priv->start_rx = 0;
1242 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT |
1243 					     PCH_UART_HAL_RX_ERR_INT);
1244 }
1245 
1246 /* Enable the modem status interrupts. */
1247 static void pch_uart_enable_ms(struct uart_port *port)
1248 {
1249 	struct eg20t_port *priv;
1250 	priv = container_of(port, struct eg20t_port, port);
1251 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_MS_INT);
1252 }
1253 
1254 /* Control the transmission of a break signal. */
1255 static void pch_uart_break_ctl(struct uart_port *port, int ctl)
1256 {
1257 	struct eg20t_port *priv;
1258 	unsigned long flags;
1259 
1260 	priv = container_of(port, struct eg20t_port, port);
1261 	spin_lock_irqsave(&priv->lock, flags);
1262 	pch_uart_hal_set_break(priv, ctl);
1263 	spin_unlock_irqrestore(&priv->lock, flags);
1264 }
1265 
1266 /* Grab any interrupt resources and initialise any low level driver state. */
1267 static int pch_uart_startup(struct uart_port *port)
1268 {
1269 	struct eg20t_port *priv;
1270 	int ret;
1271 	int fifo_size;
1272 	int trigger_level;
1273 
1274 	priv = container_of(port, struct eg20t_port, port);
1275 	priv->tx_empty = 1;
1276 
1277 	if (port->uartclk)
1278 		priv->uartclk = port->uartclk;
1279 	else
1280 		port->uartclk = priv->uartclk;
1281 
1282 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT);
1283 	ret = pch_uart_hal_set_line(priv, default_baud,
1284 			      PCH_UART_HAL_PARITY_NONE, PCH_UART_HAL_8BIT,
1285 			      PCH_UART_HAL_STB1);
1286 	if (ret)
1287 		return ret;
1288 
1289 	switch (priv->fifo_size) {
1290 	case 256:
1291 		fifo_size = PCH_UART_HAL_FIFO256;
1292 		break;
1293 	case 64:
1294 		fifo_size = PCH_UART_HAL_FIFO64;
1295 		break;
1296 	case 16:
1297 		fifo_size = PCH_UART_HAL_FIFO16;
1298 		break;
1299 	case 1:
1300 	default:
1301 		fifo_size = PCH_UART_HAL_FIFO_DIS;
1302 		break;
1303 	}
1304 
1305 	switch (priv->trigger) {
1306 	case PCH_UART_HAL_TRIGGER1:
1307 		trigger_level = 1;
1308 		break;
1309 	case PCH_UART_HAL_TRIGGER_L:
1310 		trigger_level = priv->fifo_size / 4;
1311 		break;
1312 	case PCH_UART_HAL_TRIGGER_M:
1313 		trigger_level = priv->fifo_size / 2;
1314 		break;
1315 	case PCH_UART_HAL_TRIGGER_H:
1316 	default:
1317 		trigger_level = priv->fifo_size - (priv->fifo_size / 8);
1318 		break;
1319 	}
1320 
1321 	priv->trigger_level = trigger_level;
1322 	ret = pch_uart_hal_set_fifo(priv, PCH_UART_HAL_DMA_MODE0,
1323 				    fifo_size, priv->trigger);
1324 	if (ret < 0)
1325 		return ret;
1326 
1327 	ret = request_irq(priv->port.irq, pch_uart_interrupt, IRQF_SHARED,
1328 			priv->irq_name, priv);
1329 	if (ret < 0)
1330 		return ret;
1331 
1332 	if (priv->use_dma)
1333 		pch_request_dma(port);
1334 
1335 	priv->start_rx = 1;
1336 	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT |
1337 					    PCH_UART_HAL_RX_ERR_INT);
1338 	uart_update_timeout(port, CS8, default_baud);
1339 
1340 	return 0;
1341 }
1342 
1343 static void pch_uart_shutdown(struct uart_port *port)
1344 {
1345 	struct eg20t_port *priv;
1346 	int ret;
1347 
1348 	priv = container_of(port, struct eg20t_port, port);
1349 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT);
1350 	pch_uart_hal_fifo_reset(priv, PCH_UART_HAL_CLR_ALL_FIFO);
1351 	ret = pch_uart_hal_set_fifo(priv, PCH_UART_HAL_DMA_MODE0,
1352 			      PCH_UART_HAL_FIFO_DIS, PCH_UART_HAL_TRIGGER1);
1353 	if (ret)
1354 		dev_err(priv->port.dev,
1355 			"pch_uart_hal_set_fifo Failed(ret=%d)\n", ret);
1356 
1357 	pch_free_dma(port);
1358 
1359 	free_irq(priv->port.irq, priv);
1360 }
1361 
1362 /* Change the port parameters, including word length, parity, stop
1363  *bits.  Update read_status_mask and ignore_status_mask to indicate
1364  *the types of events we are interested in receiving.  */
1365 static void pch_uart_set_termios(struct uart_port *port,
1366 				 struct ktermios *termios, struct ktermios *old)
1367 {
1368 	int rtn;
1369 	unsigned int baud, parity, bits, stb;
1370 	struct eg20t_port *priv;
1371 	unsigned long flags;
1372 
1373 	priv = container_of(port, struct eg20t_port, port);
1374 	switch (termios->c_cflag & CSIZE) {
1375 	case CS5:
1376 		bits = PCH_UART_HAL_5BIT;
1377 		break;
1378 	case CS6:
1379 		bits = PCH_UART_HAL_6BIT;
1380 		break;
1381 	case CS7:
1382 		bits = PCH_UART_HAL_7BIT;
1383 		break;
1384 	default:		/* CS8 */
1385 		bits = PCH_UART_HAL_8BIT;
1386 		break;
1387 	}
1388 	if (termios->c_cflag & CSTOPB)
1389 		stb = PCH_UART_HAL_STB2;
1390 	else
1391 		stb = PCH_UART_HAL_STB1;
1392 
1393 	if (termios->c_cflag & PARENB) {
1394 		if (termios->c_cflag & PARODD)
1395 			parity = PCH_UART_HAL_PARITY_ODD;
1396 		else
1397 			parity = PCH_UART_HAL_PARITY_EVEN;
1398 
1399 	} else
1400 		parity = PCH_UART_HAL_PARITY_NONE;
1401 
1402 	/* Only UART0 has auto hardware flow function */
1403 	if ((termios->c_cflag & CRTSCTS) && (priv->fifo_size == 256))
1404 		priv->mcr |= UART_MCR_AFE;
1405 	else
1406 		priv->mcr &= ~UART_MCR_AFE;
1407 
1408 	termios->c_cflag &= ~CMSPAR; /* Mark/Space parity is not supported */
1409 
1410 	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk / 16);
1411 
1412 	spin_lock_irqsave(&priv->lock, flags);
1413 	spin_lock(&port->lock);
1414 
1415 	uart_update_timeout(port, termios->c_cflag, baud);
1416 	rtn = pch_uart_hal_set_line(priv, baud, parity, bits, stb);
1417 	if (rtn)
1418 		goto out;
1419 
1420 	pch_uart_set_mctrl(&priv->port, priv->port.mctrl);
1421 	/* Don't rewrite B0 */
1422 	if (tty_termios_baud_rate(termios))
1423 		tty_termios_encode_baud_rate(termios, baud, baud);
1424 
1425 out:
1426 	spin_unlock(&port->lock);
1427 	spin_unlock_irqrestore(&priv->lock, flags);
1428 }
1429 
1430 static const char *pch_uart_type(struct uart_port *port)
1431 {
1432 	return KBUILD_MODNAME;
1433 }
1434 
1435 static void pch_uart_release_port(struct uart_port *port)
1436 {
1437 	struct eg20t_port *priv;
1438 
1439 	priv = container_of(port, struct eg20t_port, port);
1440 	pci_iounmap(priv->pdev, priv->membase);
1441 	pci_release_regions(priv->pdev);
1442 }
1443 
1444 static int pch_uart_request_port(struct uart_port *port)
1445 {
1446 	struct eg20t_port *priv;
1447 	int ret;
1448 	void __iomem *membase;
1449 
1450 	priv = container_of(port, struct eg20t_port, port);
1451 	ret = pci_request_regions(priv->pdev, KBUILD_MODNAME);
1452 	if (ret < 0)
1453 		return -EBUSY;
1454 
1455 	membase = pci_iomap(priv->pdev, 1, 0);
1456 	if (!membase) {
1457 		pci_release_regions(priv->pdev);
1458 		return -EBUSY;
1459 	}
1460 	priv->membase = port->membase = membase;
1461 
1462 	return 0;
1463 }
1464 
1465 static void pch_uart_config_port(struct uart_port *port, int type)
1466 {
1467 	struct eg20t_port *priv;
1468 
1469 	priv = container_of(port, struct eg20t_port, port);
1470 	if (type & UART_CONFIG_TYPE) {
1471 		port->type = priv->port_type;
1472 		pch_uart_request_port(port);
1473 	}
1474 }
1475 
1476 static int pch_uart_verify_port(struct uart_port *port,
1477 				struct serial_struct *serinfo)
1478 {
1479 	struct eg20t_port *priv;
1480 
1481 	priv = container_of(port, struct eg20t_port, port);
1482 	if (serinfo->flags & UPF_LOW_LATENCY) {
1483 		dev_info(priv->port.dev,
1484 			"PCH UART : Use PIO Mode (without DMA)\n");
1485 		priv->use_dma = 0;
1486 		serinfo->flags &= ~UPF_LOW_LATENCY;
1487 	} else {
1488 #ifndef CONFIG_PCH_DMA
1489 		dev_err(priv->port.dev, "%s : PCH DMA is not Loaded.\n",
1490 			__func__);
1491 		return -EOPNOTSUPP;
1492 #endif
1493 		if (!priv->use_dma) {
1494 			pch_request_dma(port);
1495 			if (priv->chan_rx)
1496 				priv->use_dma = 1;
1497 		}
1498 		dev_info(priv->port.dev, "PCH UART: %s\n",
1499 				priv->use_dma ?
1500 				"Use DMA Mode" : "No DMA");
1501 	}
1502 
1503 	return 0;
1504 }
1505 
1506 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_PCH_UART_CONSOLE)
1507 /*
1508  *	Wait for transmitter & holding register to empty
1509  */
1510 static void wait_for_xmitr(struct eg20t_port *up, int bits)
1511 {
1512 	unsigned int status, tmout = 10000;
1513 
1514 	/* Wait up to 10ms for the character(s) to be sent. */
1515 	for (;;) {
1516 		status = ioread8(up->membase + UART_LSR);
1517 
1518 		if ((status & bits) == bits)
1519 			break;
1520 		if (--tmout == 0)
1521 			break;
1522 		udelay(1);
1523 	}
1524 
1525 	/* Wait up to 1s for flow control if necessary */
1526 	if (up->port.flags & UPF_CONS_FLOW) {
1527 		unsigned int tmout;
1528 		for (tmout = 1000000; tmout; tmout--) {
1529 			unsigned int msr = ioread8(up->membase + UART_MSR);
1530 			if (msr & UART_MSR_CTS)
1531 				break;
1532 			udelay(1);
1533 			touch_nmi_watchdog();
1534 		}
1535 	}
1536 }
1537 #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_PCH_UART_CONSOLE */
1538 
1539 #ifdef CONFIG_CONSOLE_POLL
1540 /*
1541  * Console polling routines for communicate via uart while
1542  * in an interrupt or debug context.
1543  */
1544 static int pch_uart_get_poll_char(struct uart_port *port)
1545 {
1546 	struct eg20t_port *priv =
1547 		container_of(port, struct eg20t_port, port);
1548 	u8 lsr = ioread8(priv->membase + UART_LSR);
1549 
1550 	if (!(lsr & UART_LSR_DR))
1551 		return NO_POLL_CHAR;
1552 
1553 	return ioread8(priv->membase + PCH_UART_RBR);
1554 }
1555 
1556 
1557 static void pch_uart_put_poll_char(struct uart_port *port,
1558 			 unsigned char c)
1559 {
1560 	unsigned int ier;
1561 	struct eg20t_port *priv =
1562 		container_of(port, struct eg20t_port, port);
1563 
1564 	/*
1565 	 * First save the IER then disable the interrupts
1566 	 */
1567 	ier = ioread8(priv->membase + UART_IER);
1568 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT);
1569 
1570 	wait_for_xmitr(priv, UART_LSR_THRE);
1571 	/*
1572 	 * Send the character out.
1573 	 */
1574 	iowrite8(c, priv->membase + PCH_UART_THR);
1575 
1576 	/*
1577 	 * Finally, wait for transmitter to become empty
1578 	 * and restore the IER
1579 	 */
1580 	wait_for_xmitr(priv, BOTH_EMPTY);
1581 	iowrite8(ier, priv->membase + UART_IER);
1582 }
1583 #endif /* CONFIG_CONSOLE_POLL */
1584 
1585 static const struct uart_ops pch_uart_ops = {
1586 	.tx_empty = pch_uart_tx_empty,
1587 	.set_mctrl = pch_uart_set_mctrl,
1588 	.get_mctrl = pch_uart_get_mctrl,
1589 	.stop_tx = pch_uart_stop_tx,
1590 	.start_tx = pch_uart_start_tx,
1591 	.stop_rx = pch_uart_stop_rx,
1592 	.enable_ms = pch_uart_enable_ms,
1593 	.break_ctl = pch_uart_break_ctl,
1594 	.startup = pch_uart_startup,
1595 	.shutdown = pch_uart_shutdown,
1596 	.set_termios = pch_uart_set_termios,
1597 /*	.pm		= pch_uart_pm,		Not supported yet */
1598 	.type = pch_uart_type,
1599 	.release_port = pch_uart_release_port,
1600 	.request_port = pch_uart_request_port,
1601 	.config_port = pch_uart_config_port,
1602 	.verify_port = pch_uart_verify_port,
1603 #ifdef CONFIG_CONSOLE_POLL
1604 	.poll_get_char = pch_uart_get_poll_char,
1605 	.poll_put_char = pch_uart_put_poll_char,
1606 #endif
1607 };
1608 
1609 #ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
1610 
1611 static void pch_console_putchar(struct uart_port *port, int ch)
1612 {
1613 	struct eg20t_port *priv =
1614 		container_of(port, struct eg20t_port, port);
1615 
1616 	wait_for_xmitr(priv, UART_LSR_THRE);
1617 	iowrite8(ch, priv->membase + PCH_UART_THR);
1618 }
1619 
1620 /*
1621  *	Print a string to the serial port trying not to disturb
1622  *	any possible real use of the port...
1623  *
1624  *	The console_lock must be held when we get here.
1625  */
1626 static void
1627 pch_console_write(struct console *co, const char *s, unsigned int count)
1628 {
1629 	struct eg20t_port *priv;
1630 	unsigned long flags;
1631 	int priv_locked = 1;
1632 	int port_locked = 1;
1633 	u8 ier;
1634 
1635 	priv = pch_uart_ports[co->index];
1636 
1637 	touch_nmi_watchdog();
1638 
1639 	local_irq_save(flags);
1640 	if (priv->port.sysrq) {
1641 		/* call to uart_handle_sysrq_char already took the priv lock */
1642 		priv_locked = 0;
1643 		/* serial8250_handle_port() already took the port lock */
1644 		port_locked = 0;
1645 	} else if (oops_in_progress) {
1646 		priv_locked = spin_trylock(&priv->lock);
1647 		port_locked = spin_trylock(&priv->port.lock);
1648 	} else {
1649 		spin_lock(&priv->lock);
1650 		spin_lock(&priv->port.lock);
1651 	}
1652 
1653 	/*
1654 	 *	First save the IER then disable the interrupts
1655 	 */
1656 	ier = ioread8(priv->membase + UART_IER);
1657 
1658 	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_ALL_INT);
1659 
1660 	uart_console_write(&priv->port, s, count, pch_console_putchar);
1661 
1662 	/*
1663 	 *	Finally, wait for transmitter to become empty
1664 	 *	and restore the IER
1665 	 */
1666 	wait_for_xmitr(priv, BOTH_EMPTY);
1667 	iowrite8(ier, priv->membase + UART_IER);
1668 
1669 	if (port_locked)
1670 		spin_unlock(&priv->port.lock);
1671 	if (priv_locked)
1672 		spin_unlock(&priv->lock);
1673 	local_irq_restore(flags);
1674 }
1675 
1676 static int __init pch_console_setup(struct console *co, char *options)
1677 {
1678 	struct uart_port *port;
1679 	int baud = default_baud;
1680 	int bits = 8;
1681 	int parity = 'n';
1682 	int flow = 'n';
1683 
1684 	/*
1685 	 * Check whether an invalid uart number has been specified, and
1686 	 * if so, search for the first available port that does have
1687 	 * console support.
1688 	 */
1689 	if (co->index >= PCH_UART_NR)
1690 		co->index = 0;
1691 	port = &pch_uart_ports[co->index]->port;
1692 
1693 	if (!port || (!port->iobase && !port->membase))
1694 		return -ENODEV;
1695 
1696 	port->uartclk = pch_uart_get_uartclk();
1697 
1698 	if (options)
1699 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1700 
1701 	return uart_set_options(port, co, baud, parity, bits, flow);
1702 }
1703 
1704 static struct uart_driver pch_uart_driver;
1705 
1706 static struct console pch_console = {
1707 	.name		= PCH_UART_DRIVER_DEVICE,
1708 	.write		= pch_console_write,
1709 	.device		= uart_console_device,
1710 	.setup		= pch_console_setup,
1711 	.flags		= CON_PRINTBUFFER | CON_ANYTIME,
1712 	.index		= -1,
1713 	.data		= &pch_uart_driver,
1714 };
1715 
1716 #define PCH_CONSOLE	(&pch_console)
1717 #else
1718 #define PCH_CONSOLE	NULL
1719 #endif	/* CONFIG_SERIAL_PCH_UART_CONSOLE */
1720 
1721 static struct uart_driver pch_uart_driver = {
1722 	.owner = THIS_MODULE,
1723 	.driver_name = KBUILD_MODNAME,
1724 	.dev_name = PCH_UART_DRIVER_DEVICE,
1725 	.major = 0,
1726 	.minor = 0,
1727 	.nr = PCH_UART_NR,
1728 	.cons = PCH_CONSOLE,
1729 };
1730 
1731 static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
1732 					     const struct pci_device_id *id)
1733 {
1734 	struct eg20t_port *priv;
1735 	int ret;
1736 	unsigned int iobase;
1737 	unsigned int mapbase;
1738 	unsigned char *rxbuf;
1739 	int fifosize;
1740 	int port_type;
1741 	struct pch_uart_driver_data *board;
1742 #ifdef CONFIG_DEBUG_FS
1743 	char name[32];	/* for debugfs file name */
1744 #endif
1745 
1746 	board = &drv_dat[id->driver_data];
1747 	port_type = board->port_type;
1748 
1749 	priv = kzalloc(sizeof(struct eg20t_port), GFP_KERNEL);
1750 	if (priv == NULL)
1751 		goto init_port_alloc_err;
1752 
1753 	rxbuf = (unsigned char *)__get_free_page(GFP_KERNEL);
1754 	if (!rxbuf)
1755 		goto init_port_free_txbuf;
1756 
1757 	switch (port_type) {
1758 	case PORT_PCH_8LINE:
1759 		fifosize = 256; /* EG20T/ML7213: UART0 */
1760 		break;
1761 	case PORT_PCH_2LINE:
1762 		fifosize = 64; /* EG20T:UART1~3  ML7213: UART1~2*/
1763 		break;
1764 	default:
1765 		dev_err(&pdev->dev, "Invalid Port Type(=%d)\n", port_type);
1766 		goto init_port_hal_free;
1767 	}
1768 
1769 	pci_enable_msi(pdev);
1770 	pci_set_master(pdev);
1771 
1772 	spin_lock_init(&priv->lock);
1773 
1774 	iobase = pci_resource_start(pdev, 0);
1775 	mapbase = pci_resource_start(pdev, 1);
1776 	priv->mapbase = mapbase;
1777 	priv->iobase = iobase;
1778 	priv->pdev = pdev;
1779 	priv->tx_empty = 1;
1780 	priv->rxbuf.buf = rxbuf;
1781 	priv->rxbuf.size = PAGE_SIZE;
1782 
1783 	priv->fifo_size = fifosize;
1784 	priv->uartclk = pch_uart_get_uartclk();
1785 	priv->port_type = port_type;
1786 	priv->port.dev = &pdev->dev;
1787 	priv->port.iobase = iobase;
1788 	priv->port.membase = NULL;
1789 	priv->port.mapbase = mapbase;
1790 	priv->port.irq = pdev->irq;
1791 	priv->port.iotype = UPIO_PORT;
1792 	priv->port.ops = &pch_uart_ops;
1793 	priv->port.flags = UPF_BOOT_AUTOCONF;
1794 	priv->port.fifosize = fifosize;
1795 	priv->port.line = board->line_no;
1796 	priv->trigger = PCH_UART_HAL_TRIGGER_M;
1797 
1798 	snprintf(priv->irq_name, IRQ_NAME_SIZE,
1799 		 KBUILD_MODNAME ":" PCH_UART_DRIVER_DEVICE "%d",
1800 		 priv->port.line);
1801 
1802 	spin_lock_init(&priv->port.lock);
1803 
1804 	pci_set_drvdata(pdev, priv);
1805 	priv->trigger_level = 1;
1806 	priv->fcr = 0;
1807 
1808 	if (pdev->dev.of_node)
1809 		of_property_read_u32(pdev->dev.of_node, "clock-frequency"
1810 					 , &user_uartclk);
1811 
1812 #ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
1813 	pch_uart_ports[board->line_no] = priv;
1814 #endif
1815 	ret = uart_add_one_port(&pch_uart_driver, &priv->port);
1816 	if (ret < 0)
1817 		goto init_port_hal_free;
1818 
1819 #ifdef CONFIG_DEBUG_FS
1820 	snprintf(name, sizeof(name), "uart%d_regs", board->line_no);
1821 	priv->debugfs = debugfs_create_file(name, S_IFREG | S_IRUGO,
1822 				NULL, priv, &port_regs_ops);
1823 #endif
1824 
1825 	return priv;
1826 
1827 init_port_hal_free:
1828 #ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
1829 	pch_uart_ports[board->line_no] = NULL;
1830 #endif
1831 	free_page((unsigned long)rxbuf);
1832 init_port_free_txbuf:
1833 	kfree(priv);
1834 init_port_alloc_err:
1835 
1836 	return NULL;
1837 }
1838 
1839 static void pch_uart_exit_port(struct eg20t_port *priv)
1840 {
1841 
1842 #ifdef CONFIG_DEBUG_FS
1843 	debugfs_remove(priv->debugfs);
1844 #endif
1845 	uart_remove_one_port(&pch_uart_driver, &priv->port);
1846 	free_page((unsigned long)priv->rxbuf.buf);
1847 }
1848 
1849 static void pch_uart_pci_remove(struct pci_dev *pdev)
1850 {
1851 	struct eg20t_port *priv = pci_get_drvdata(pdev);
1852 
1853 	pci_disable_msi(pdev);
1854 
1855 #ifdef CONFIG_SERIAL_PCH_UART_CONSOLE
1856 	pch_uart_ports[priv->port.line] = NULL;
1857 #endif
1858 	pch_uart_exit_port(priv);
1859 	pci_disable_device(pdev);
1860 	kfree(priv);
1861 	return;
1862 }
1863 #ifdef CONFIG_PM
1864 static int pch_uart_pci_suspend(struct pci_dev *pdev, pm_message_t state)
1865 {
1866 	struct eg20t_port *priv = pci_get_drvdata(pdev);
1867 
1868 	uart_suspend_port(&pch_uart_driver, &priv->port);
1869 
1870 	pci_save_state(pdev);
1871 	pci_set_power_state(pdev, pci_choose_state(pdev, state));
1872 	return 0;
1873 }
1874 
1875 static int pch_uart_pci_resume(struct pci_dev *pdev)
1876 {
1877 	struct eg20t_port *priv = pci_get_drvdata(pdev);
1878 	int ret;
1879 
1880 	pci_set_power_state(pdev, PCI_D0);
1881 	pci_restore_state(pdev);
1882 
1883 	ret = pci_enable_device(pdev);
1884 	if (ret) {
1885 		dev_err(&pdev->dev,
1886 		"%s-pci_enable_device failed(ret=%d) ", __func__, ret);
1887 		return ret;
1888 	}
1889 
1890 	uart_resume_port(&pch_uart_driver, &priv->port);
1891 
1892 	return 0;
1893 }
1894 #else
1895 #define pch_uart_pci_suspend NULL
1896 #define pch_uart_pci_resume NULL
1897 #endif
1898 
1899 static const struct pci_device_id pch_uart_pci_id[] = {
1900 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8811),
1901 	 .driver_data = pch_et20t_uart0},
1902 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8812),
1903 	 .driver_data = pch_et20t_uart1},
1904 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8813),
1905 	 .driver_data = pch_et20t_uart2},
1906 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8814),
1907 	 .driver_data = pch_et20t_uart3},
1908 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8027),
1909 	 .driver_data = pch_ml7213_uart0},
1910 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8028),
1911 	 .driver_data = pch_ml7213_uart1},
1912 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8029),
1913 	 .driver_data = pch_ml7213_uart2},
1914 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x800C),
1915 	 .driver_data = pch_ml7223_uart0},
1916 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x800D),
1917 	 .driver_data = pch_ml7223_uart1},
1918 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8811),
1919 	 .driver_data = pch_ml7831_uart0},
1920 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8812),
1921 	 .driver_data = pch_ml7831_uart1},
1922 	{0,},
1923 };
1924 
1925 static int pch_uart_pci_probe(struct pci_dev *pdev,
1926 					const struct pci_device_id *id)
1927 {
1928 	int ret;
1929 	struct eg20t_port *priv;
1930 
1931 	ret = pci_enable_device(pdev);
1932 	if (ret < 0)
1933 		goto probe_error;
1934 
1935 	priv = pch_uart_init_port(pdev, id);
1936 	if (!priv) {
1937 		ret = -EBUSY;
1938 		goto probe_disable_device;
1939 	}
1940 	pci_set_drvdata(pdev, priv);
1941 
1942 	return ret;
1943 
1944 probe_disable_device:
1945 	pci_disable_msi(pdev);
1946 	pci_disable_device(pdev);
1947 probe_error:
1948 	return ret;
1949 }
1950 
1951 static struct pci_driver pch_uart_pci_driver = {
1952 	.name = "pch_uart",
1953 	.id_table = pch_uart_pci_id,
1954 	.probe = pch_uart_pci_probe,
1955 	.remove = pch_uart_pci_remove,
1956 	.suspend = pch_uart_pci_suspend,
1957 	.resume = pch_uart_pci_resume,
1958 };
1959 
1960 static int __init pch_uart_module_init(void)
1961 {
1962 	int ret;
1963 
1964 	/* register as UART driver */
1965 	ret = uart_register_driver(&pch_uart_driver);
1966 	if (ret < 0)
1967 		return ret;
1968 
1969 	/* register as PCI driver */
1970 	ret = pci_register_driver(&pch_uart_pci_driver);
1971 	if (ret < 0)
1972 		uart_unregister_driver(&pch_uart_driver);
1973 
1974 	return ret;
1975 }
1976 module_init(pch_uart_module_init);
1977 
1978 static void __exit pch_uart_module_exit(void)
1979 {
1980 	pci_unregister_driver(&pch_uart_pci_driver);
1981 	uart_unregister_driver(&pch_uart_driver);
1982 }
1983 module_exit(pch_uart_module_exit);
1984 
1985 MODULE_LICENSE("GPL v2");
1986 MODULE_DESCRIPTION("Intel EG20T PCH UART PCI Driver");
1987 MODULE_DEVICE_TABLE(pci, pch_uart_pci_id);
1988 
1989 module_param(default_baud, uint, S_IRUGO);
1990 MODULE_PARM_DESC(default_baud,
1991                  "Default BAUD for initial driver state and console (default 9600)");
1992 module_param(user_uartclk, uint, S_IRUGO);
1993 MODULE_PARM_DESC(user_uartclk,
1994                  "Override UART default or board specific UART clock");
1995