1 /*
2  * Driver for the 98626/98644/internal serial interface on hp300/hp400
3  * (based on the National Semiconductor INS8250/NS16550AF/WD16C552 UARTs)
4  *
5  * Ported from 2.2 and modified to use the normal 8250 driver
6  * by Kars de Jong <jongk@linux-m68k.org>, May 2004.
7  */
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/string.h>
11 #include <linux/kernel.h>
12 #include <linux/serial.h>
13 #include <linux/serial_8250.h>
14 #include <linux/delay.h>
15 #include <linux/dio.h>
16 #include <linux/console.h>
17 #include <linux/slab.h>
18 #include <asm/io.h>
19 
20 #include "8250.h"
21 
22 #if !defined(CONFIG_HPDCA) && !defined(CONFIG_HPAPCI) && !defined(CONFIG_COMPILE_TEST)
23 #warning CONFIG_SERIAL_8250 defined but neither CONFIG_HPDCA nor CONFIG_HPAPCI defined, are you sure?
24 #endif
25 
26 #ifdef CONFIG_HPAPCI
27 struct hp300_port {
28 	struct hp300_port *next;	/* next port */
29 	int line;			/* line (tty) number */
30 };
31 
32 static struct hp300_port *hp300_ports;
33 #endif
34 
35 #ifdef CONFIG_HPDCA
36 
37 static int hpdca_init_one(struct dio_dev *d,
38 					const struct dio_device_id *ent);
39 static void hpdca_remove_one(struct dio_dev *d);
40 
41 static struct dio_device_id hpdca_dio_tbl[] = {
42 	{ DIO_ID_DCA0 },
43 	{ DIO_ID_DCA0REM },
44 	{ DIO_ID_DCA1 },
45 	{ DIO_ID_DCA1REM },
46 	{ 0 }
47 };
48 
49 static struct dio_driver hpdca_driver = {
50 	.name      = "hpdca",
51 	.id_table  = hpdca_dio_tbl,
52 	.probe     = hpdca_init_one,
53 	.remove    = hpdca_remove_one,
54 };
55 
56 #endif
57 
58 static unsigned int num_ports;
59 
60 extern int hp300_uart_scode;
61 
62 /* Offset to UART registers from base of DCA */
63 #define UART_OFFSET	17
64 
65 #define DCA_ID		0x01	/* ID (read), reset (write) */
66 #define DCA_IC		0x03	/* Interrupt control        */
67 
68 /* Interrupt control */
69 #define DCA_IC_IE	0x80	/* Master interrupt enable  */
70 
71 #define HPDCA_BAUD_BASE 153600
72 
73 /* Base address of the Frodo part */
74 #define FRODO_BASE	(0x41c000)
75 
76 /*
77  * Where we find the 8250-like APCI ports, and how far apart they are.
78  */
79 #define FRODO_APCIBASE		0x0
80 #define FRODO_APCISPACE		0x20
81 #define FRODO_APCI_OFFSET(x)	(FRODO_APCIBASE + ((x) * FRODO_APCISPACE))
82 
83 #define HPAPCI_BAUD_BASE 500400
84 
85 #ifdef CONFIG_SERIAL_8250_CONSOLE
86 /*
87  * Parse the bootinfo to find descriptions for headless console and
88  * debug serial ports and register them with the 8250 driver.
89  */
90 int __init hp300_setup_serial_console(void)
91 {
92 	int scode;
93 	struct uart_port port;
94 
95 	memset(&port, 0, sizeof(port));
96 
97 	if (hp300_uart_scode < 0 || hp300_uart_scode > DIO_SCMAX)
98 		return 0;
99 
100 	if (DIO_SCINHOLE(hp300_uart_scode))
101 		return 0;
102 
103 	scode = hp300_uart_scode;
104 
105 	/* Memory mapped I/O */
106 	port.iotype = UPIO_MEM;
107 	port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
108 	port.type = PORT_UNKNOWN;
109 
110 	/* Check for APCI console */
111 	if (scode == 256) {
112 #ifdef CONFIG_HPAPCI
113 		pr_info("Serial console is HP APCI 1\n");
114 
115 		port.uartclk = HPAPCI_BAUD_BASE * 16;
116 		port.mapbase = (FRODO_BASE + FRODO_APCI_OFFSET(1));
117 		port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
118 		port.regshift = 2;
119 		add_preferred_console("ttyS", port.line, "9600n8");
120 #else
121 		pr_warn("Serial console is APCI but support is disabled (CONFIG_HPAPCI)!\n");
122 		return 0;
123 #endif
124 	} else {
125 #ifdef CONFIG_HPDCA
126 		unsigned long pa = dio_scodetophysaddr(scode);
127 		if (!pa)
128 			return 0;
129 
130 		pr_info("Serial console is HP DCA at select code %d\n", scode);
131 
132 		port.uartclk = HPDCA_BAUD_BASE * 16;
133 		port.mapbase = (pa + UART_OFFSET);
134 		port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
135 		port.regshift = 1;
136 		port.irq = DIO_IPL(pa + DIO_VIRADDRBASE);
137 
138 		/* Enable board-interrupts */
139 		out_8(pa + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
140 
141 		if (DIO_ID(pa + DIO_VIRADDRBASE) & 0x80)
142 			add_preferred_console("ttyS", port.line, "9600n8");
143 #else
144 		pr_warn("Serial console is DCA but support is disabled (CONFIG_HPDCA)!\n");
145 		return 0;
146 #endif
147 	}
148 
149 	if (early_serial_setup(&port) < 0)
150 		pr_warn("%s: early_serial_setup() failed.\n", __func__);
151 	return 0;
152 }
153 #endif /* CONFIG_SERIAL_8250_CONSOLE */
154 
155 #ifdef CONFIG_HPDCA
156 static int hpdca_init_one(struct dio_dev *d,
157 				const struct dio_device_id *ent)
158 {
159 	struct uart_8250_port uart;
160 	int line;
161 
162 #ifdef CONFIG_SERIAL_8250_CONSOLE
163 	if (hp300_uart_scode == d->scode) {
164 		/* Already got it. */
165 		return 0;
166 	}
167 #endif
168 	memset(&uart, 0, sizeof(uart));
169 
170 	/* Memory mapped I/O */
171 	uart.port.iotype = UPIO_MEM;
172 	uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
173 	uart.port.irq = d->ipl;
174 	uart.port.uartclk = HPDCA_BAUD_BASE * 16;
175 	uart.port.mapbase = (d->resource.start + UART_OFFSET);
176 	uart.port.membase = (char *)(uart.port.mapbase + DIO_VIRADDRBASE);
177 	uart.port.regshift = 1;
178 	uart.port.dev = &d->dev;
179 	line = serial8250_register_8250_port(&uart);
180 
181 	if (line < 0) {
182 		dev_notice(&d->dev,
183 			  "8250_hp300: register_serial() DCA scode %d irq %d failed\n",
184 			  d->scode, uart.port.irq);
185 		return -ENOMEM;
186 	}
187 
188 	/* Enable board-interrupts */
189 	out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
190 	dio_set_drvdata(d, (void *)line);
191 
192 	/* Reset the DCA */
193 	out_8(d->resource.start + DIO_VIRADDRBASE + DCA_ID, 0xff);
194 	udelay(100);
195 
196 	num_ports++;
197 
198 	return 0;
199 }
200 #endif
201 
202 static int __init hp300_8250_init(void)
203 {
204 	static int called;
205 #ifdef CONFIG_HPAPCI
206 	int line;
207 	unsigned long base;
208 	struct uart_8250_port uart;
209 	struct hp300_port *port;
210 	int i;
211 #endif
212 	if (called)
213 		return -ENODEV;
214 	called = 1;
215 
216 	if (!MACH_IS_HP300)
217 		return -ENODEV;
218 
219 #ifdef CONFIG_HPDCA
220 	dio_register_driver(&hpdca_driver);
221 #endif
222 #ifdef CONFIG_HPAPCI
223 	if (hp300_model < HP_400) {
224 		if (!num_ports)
225 			return -ENODEV;
226 		return 0;
227 	}
228 	/* These models have the Frodo chip.
229 	 * Port 0 is reserved for the Apollo Domain keyboard.
230 	 * Port 1 is either the console or the DCA.
231 	 */
232 	for (i = 1; i < 4; i++) {
233 		/* Port 1 is the console on a 425e, on other machines it's
234 		 * mapped to DCA.
235 		 */
236 #ifdef CONFIG_SERIAL_8250_CONSOLE
237 		if (i == 1)
238 			continue;
239 #endif
240 
241 		/* Create new serial device */
242 		port = kmalloc(sizeof(struct hp300_port), GFP_KERNEL);
243 		if (!port)
244 			return -ENOMEM;
245 
246 		memset(&uart, 0, sizeof(uart));
247 
248 		base = (FRODO_BASE + FRODO_APCI_OFFSET(i));
249 
250 		/* Memory mapped I/O */
251 		uart.port.iotype = UPIO_MEM;
252 		uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ
253 				| UPF_BOOT_AUTOCONF;
254 		/* XXX - no interrupt support yet */
255 		uart.port.irq = 0;
256 		uart.port.uartclk = HPAPCI_BAUD_BASE * 16;
257 		uart.port.mapbase = base;
258 		uart.port.membase = (char *)(base + DIO_VIRADDRBASE);
259 		uart.port.regshift = 2;
260 
261 		line = serial8250_register_8250_port(&uart);
262 
263 		if (line < 0) {
264 			dev_notice(uart.port.dev,
265 				   "8250_hp300: register_serial() APCI %d irq %d failed\n",
266 				   i, uart.port.irq);
267 			kfree(port);
268 			continue;
269 		}
270 
271 		port->line = line;
272 		port->next = hp300_ports;
273 		hp300_ports = port;
274 
275 		num_ports++;
276 	}
277 #endif
278 
279 	/* Any boards found? */
280 	if (!num_ports)
281 		return -ENODEV;
282 
283 	return 0;
284 }
285 
286 #ifdef CONFIG_HPDCA
287 static void hpdca_remove_one(struct dio_dev *d)
288 {
289 	int line;
290 
291 	line = (int) dio_get_drvdata(d);
292 	if (d->resource.start) {
293 		/* Disable board-interrupts */
294 		out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, 0);
295 	}
296 	serial8250_unregister_port(line);
297 }
298 #endif
299 
300 static void __exit hp300_8250_exit(void)
301 {
302 #ifdef CONFIG_HPAPCI
303 	struct hp300_port *port, *to_free;
304 
305 	for (port = hp300_ports; port; ) {
306 		serial8250_unregister_port(port->line);
307 		to_free = port;
308 		port = port->next;
309 		kfree(to_free);
310 	}
311 
312 	hp300_ports = NULL;
313 #endif
314 #ifdef CONFIG_HPDCA
315 	dio_unregister_driver(&hpdca_driver);
316 #endif
317 }
318 
319 module_init(hp300_8250_init);
320 module_exit(hp300_8250_exit);
321 MODULE_DESCRIPTION("HP DCA/APCI serial driver");
322 MODULE_AUTHOR("Kars de Jong <jongk@linux-m68k.org>");
323 MODULE_LICENSE("GPL");
324