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_core.h>
14 #include <linux/serial_8250.h>
15 #include <linux/delay.h>
16 #include <linux/dio.h>
17 #include <linux/console.h>
18 #include <linux/slab.h>
19 #include <asm/io.h>
20 
21 #include "8250.h"
22 
23 #if !defined(CONFIG_HPDCA) && !defined(CONFIG_HPAPCI)
24 #warning CONFIG_SERIAL_8250 defined but neither CONFIG_HPDCA nor CONFIG_HPAPCI defined, are you sure?
25 #endif
26 
27 #ifdef CONFIG_HPAPCI
28 struct hp300_port
29 {
30 	struct hp300_port *next;	/* next port */
31 	int line;			/* line (tty) number */
32 };
33 
34 static struct hp300_port *hp300_ports;
35 #endif
36 
37 #ifdef CONFIG_HPDCA
38 
39 static int hpdca_init_one(struct dio_dev *d,
40 					const struct dio_device_id *ent);
41 static void hpdca_remove_one(struct dio_dev *d);
42 
43 static struct dio_device_id hpdca_dio_tbl[] = {
44 	{ DIO_ID_DCA0 },
45 	{ DIO_ID_DCA0REM },
46 	{ DIO_ID_DCA1 },
47 	{ DIO_ID_DCA1REM },
48 	{ 0 }
49 };
50 
51 static struct dio_driver hpdca_driver = {
52 	.name      = "hpdca",
53 	.id_table  = hpdca_dio_tbl,
54 	.probe     = hpdca_init_one,
55 	.remove    = hpdca_remove_one,
56 };
57 
58 #endif
59 
60 static unsigned int num_ports;
61 
62 extern int hp300_uart_scode;
63 
64 /* Offset to UART registers from base of DCA */
65 #define UART_OFFSET	17
66 
67 #define DCA_ID		0x01	/* ID (read), reset (write) */
68 #define DCA_IC		0x03	/* Interrupt control        */
69 
70 /* Interrupt control */
71 #define DCA_IC_IE	0x80	/* Master interrupt enable  */
72 
73 #define HPDCA_BAUD_BASE 153600
74 
75 /* Base address of the Frodo part */
76 #define FRODO_BASE	(0x41c000)
77 
78 /*
79  * Where we find the 8250-like APCI ports, and how far apart they are.
80  */
81 #define FRODO_APCIBASE		0x0
82 #define FRODO_APCISPACE		0x20
83 #define FRODO_APCI_OFFSET(x)	(FRODO_APCIBASE + ((x) * FRODO_APCISPACE))
84 
85 #define HPAPCI_BAUD_BASE 500400
86 
87 #ifdef CONFIG_SERIAL_8250_CONSOLE
88 /*
89  * Parse the bootinfo to find descriptions for headless console and
90  * debug serial ports and register them with the 8250 driver.
91  */
92 int __init hp300_setup_serial_console(void)
93 {
94 	int scode;
95 	struct uart_port port;
96 
97 	memset(&port, 0, sizeof(port));
98 
99 	if (hp300_uart_scode < 0 || hp300_uart_scode > DIO_SCMAX)
100 		return 0;
101 
102 	if (DIO_SCINHOLE(hp300_uart_scode))
103 		return 0;
104 
105 	scode = hp300_uart_scode;
106 
107 	/* Memory mapped I/O */
108 	port.iotype = UPIO_MEM;
109 	port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
110 	port.type = PORT_UNKNOWN;
111 
112 	/* Check for APCI console */
113 	if (scode == 256) {
114 #ifdef CONFIG_HPAPCI
115 		printk(KERN_INFO "Serial console is HP APCI 1\n");
116 
117 		port.uartclk = HPAPCI_BAUD_BASE * 16;
118 		port.mapbase = (FRODO_BASE + FRODO_APCI_OFFSET(1));
119 		port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
120 		port.regshift = 2;
121 		add_preferred_console("ttyS", port.line, "9600n8");
122 #else
123 		printk(KERN_WARNING "Serial console is APCI but support is disabled (CONFIG_HPAPCI)!\n");
124 		return 0;
125 #endif
126 	} else {
127 #ifdef CONFIG_HPDCA
128 		unsigned long pa = dio_scodetophysaddr(scode);
129 		if (!pa)
130 			return 0;
131 
132 		printk(KERN_INFO "Serial console is HP DCA at select code %d\n", scode);
133 
134 		port.uartclk = HPDCA_BAUD_BASE * 16;
135 		port.mapbase = (pa + UART_OFFSET);
136 		port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
137 		port.regshift = 1;
138 		port.irq = DIO_IPL(pa + DIO_VIRADDRBASE);
139 
140 		/* Enable board-interrupts */
141 		out_8(pa + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
142 
143 		if (DIO_ID(pa + DIO_VIRADDRBASE) & 0x80)
144 			add_preferred_console("ttyS", port.line, "9600n8");
145 #else
146 		printk(KERN_WARNING "Serial console is DCA but support is disabled (CONFIG_HPDCA)!\n");
147 		return 0;
148 #endif
149 	}
150 
151 	if (early_serial_setup(&port) < 0)
152 		printk(KERN_WARNING "hp300_setup_serial_console(): early_serial_setup() failed.\n");
153 	return 0;
154 }
155 #endif /* CONFIG_SERIAL_8250_CONSOLE */
156 
157 #ifdef CONFIG_HPDCA
158 static int hpdca_init_one(struct dio_dev *d,
159 				const struct dio_device_id *ent)
160 {
161 	struct uart_8250_port uart;
162 	int line;
163 
164 #ifdef CONFIG_SERIAL_8250_CONSOLE
165 	if (hp300_uart_scode == d->scode) {
166 		/* Already got it. */
167 		return 0;
168 	}
169 #endif
170 	memset(&uart, 0, sizeof(uart));
171 
172 	/* Memory mapped I/O */
173 	uart.port.iotype = UPIO_MEM;
174 	uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
175 	uart.port.irq = d->ipl;
176 	uart.port.uartclk = HPDCA_BAUD_BASE * 16;
177 	uart.port.mapbase = (d->resource.start + UART_OFFSET);
178 	uart.port.membase = (char *)(uart.port.mapbase + DIO_VIRADDRBASE);
179 	uart.port.regshift = 1;
180 	uart.port.dev = &d->dev;
181 	line = serial8250_register_8250_port(&uart);
182 
183 	if (line < 0) {
184 		printk(KERN_NOTICE "8250_hp300: register_serial() DCA scode %d"
185 		       " irq %d failed\n", d->scode, uart.port.irq);
186 		return -ENOMEM;
187 	}
188 
189 	/* Enable board-interrupts */
190 	out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
191 	dio_set_drvdata(d, (void *)line);
192 
193 	/* Reset the DCA */
194 	out_8(d->resource.start + DIO_VIRADDRBASE + DCA_ID, 0xff);
195 	udelay(100);
196 
197 	num_ports++;
198 
199 	return 0;
200 }
201 #endif
202 
203 static int __init hp300_8250_init(void)
204 {
205 	static int called;
206 #ifdef CONFIG_HPAPCI
207 	int line;
208 	unsigned long base;
209 	struct uart_8250_port uart;
210 	struct hp300_port *port;
211 	int i;
212 #endif
213 	if (called)
214 		return -ENODEV;
215 	called = 1;
216 
217 	if (!MACH_IS_HP300)
218 		return -ENODEV;
219 
220 #ifdef CONFIG_HPDCA
221 	dio_register_driver(&hpdca_driver);
222 #endif
223 #ifdef CONFIG_HPAPCI
224 	if (hp300_model < HP_400) {
225 		if (!num_ports)
226 			return -ENODEV;
227 		return 0;
228 	}
229 	/* These models have the Frodo chip.
230 	 * Port 0 is reserved for the Apollo Domain keyboard.
231 	 * Port 1 is either the console or the DCA.
232 	 */
233 	for (i = 1; i < 4; i++) {
234 		/* Port 1 is the console on a 425e, on other machines it's
235 		 * mapped to DCA.
236 		 */
237 #ifdef CONFIG_SERIAL_8250_CONSOLE
238 		if (i == 1)
239 			continue;
240 #endif
241 
242 		/* Create new serial device */
243 		port = kmalloc(sizeof(struct hp300_port), GFP_KERNEL);
244 		if (!port)
245 			return -ENOMEM;
246 
247 		memset(&uart, 0, sizeof(uart));
248 
249 		base = (FRODO_BASE + FRODO_APCI_OFFSET(i));
250 
251 		/* Memory mapped I/O */
252 		uart.port.iotype = UPIO_MEM;
253 		uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ \
254 			      | UPF_BOOT_AUTOCONF;
255 		/* XXX - no interrupt support yet */
256 		uart.port.irq = 0;
257 		uart.port.uartclk = HPAPCI_BAUD_BASE * 16;
258 		uart.port.mapbase = base;
259 		uart.port.membase = (char *)(base + DIO_VIRADDRBASE);
260 		uart.port.regshift = 2;
261 
262 		line = serial8250_register_8250_port(&uart);
263 
264 		if (line < 0) {
265 			printk(KERN_NOTICE "8250_hp300: register_serial() APCI"
266 			       " %d irq %d failed\n", 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