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_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 __devinit hpdca_init_one(struct dio_dev *d,
40 					const struct dio_device_id *ent);
41 static void __devexit 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    = __devexit_p(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  * This function should be called before serial_console_init() is called
92  * to make sure the serial console will be available for use. IA-64 kernel
93  * calls this function from setup_arch() after the EFI and ACPI tables have
94  * been parsed.
95  */
hp300_setup_serial_console(void)96 int __init hp300_setup_serial_console(void)
97 {
98 	int scode;
99 	struct uart_port port;
100 
101 	memset(&port, 0, sizeof(port));
102 
103 	if (hp300_uart_scode < 0 || hp300_uart_scode > DIO_SCMAX)
104 		return 0;
105 
106 	if (DIO_SCINHOLE(hp300_uart_scode))
107 		return 0;
108 
109 	scode = hp300_uart_scode;
110 
111 	/* Memory mapped I/O */
112 	port.iotype = UPIO_MEM;
113 	port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
114 	port.type = PORT_UNKNOWN;
115 
116 	/* Check for APCI console */
117 	if (scode == 256) {
118 #ifdef CONFIG_HPAPCI
119 		printk(KERN_INFO "Serial console is HP APCI 1\n");
120 
121 		port.uartclk = HPAPCI_BAUD_BASE * 16;
122 		port.mapbase = (FRODO_BASE + FRODO_APCI_OFFSET(1));
123 		port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
124 		port.regshift = 2;
125 		add_preferred_console("ttyS", port.line, "9600n8");
126 #else
127 		printk(KERN_WARNING "Serial console is APCI but support is disabled (CONFIG_HPAPCI)!\n");
128 		return 0;
129 #endif
130 	} else {
131 #ifdef CONFIG_HPDCA
132 		unsigned long pa = dio_scodetophysaddr(scode);
133 		if (!pa)
134 			return 0;
135 
136 		printk(KERN_INFO "Serial console is HP DCA at select code %d\n", scode);
137 
138 		port.uartclk = HPDCA_BAUD_BASE * 16;
139 		port.mapbase = (pa + UART_OFFSET);
140 		port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
141 		port.regshift = 1;
142 		port.irq = DIO_IPL(pa + DIO_VIRADDRBASE);
143 
144 		/* Enable board-interrupts */
145 		out_8(pa + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
146 
147 		if (DIO_ID(pa + DIO_VIRADDRBASE) & 0x80)
148 			add_preferred_console("ttyS", port.line, "9600n8");
149 #else
150 		printk(KERN_WARNING "Serial console is DCA but support is disabled (CONFIG_HPDCA)!\n");
151 		return 0;
152 #endif
153 	}
154 
155 	if (early_serial_setup(&port) < 0)
156 		printk(KERN_WARNING "hp300_setup_serial_console(): early_serial_setup() failed.\n");
157 	return 0;
158 }
159 #endif /* CONFIG_SERIAL_8250_CONSOLE */
160 
161 #ifdef CONFIG_HPDCA
hpdca_init_one(struct dio_dev * d,const struct dio_device_id * ent)162 static int __devinit hpdca_init_one(struct dio_dev *d,
163 				const struct dio_device_id *ent)
164 {
165 	struct uart_port port;
166 	int line;
167 
168 #ifdef CONFIG_SERIAL_8250_CONSOLE
169 	if (hp300_uart_scode == d->scode) {
170 		/* Already got it. */
171 		return 0;
172 	}
173 #endif
174 	memset(&port, 0, sizeof(struct uart_port));
175 
176 	/* Memory mapped I/O */
177 	port.iotype = UPIO_MEM;
178 	port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
179 	port.irq = d->ipl;
180 	port.uartclk = HPDCA_BAUD_BASE * 16;
181 	port.mapbase = (d->resource.start + UART_OFFSET);
182 	port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
183 	port.regshift = 1;
184 	port.dev = &d->dev;
185 	line = serial8250_register_port(&port);
186 
187 	if (line < 0) {
188 		printk(KERN_NOTICE "8250_hp300: register_serial() DCA scode %d"
189 		       " irq %d failed\n", d->scode, port.irq);
190 		return -ENOMEM;
191 	}
192 
193 	/* Enable board-interrupts */
194 	out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
195 	dio_set_drvdata(d, (void *)line);
196 
197 	/* Reset the DCA */
198 	out_8(d->resource.start + DIO_VIRADDRBASE + DCA_ID, 0xff);
199 	udelay(100);
200 
201 	num_ports++;
202 
203 	return 0;
204 }
205 #endif
206 
hp300_8250_init(void)207 static int __init hp300_8250_init(void)
208 {
209 	static int called;
210 #ifdef CONFIG_HPAPCI
211 	int line;
212 	unsigned long base;
213 	struct uart_port uport;
214 	struct hp300_port *port;
215 	int i;
216 #endif
217 	if (called)
218 		return -ENODEV;
219 	called = 1;
220 
221 	if (!MACH_IS_HP300)
222 		return -ENODEV;
223 
224 #ifdef CONFIG_HPDCA
225 	dio_register_driver(&hpdca_driver);
226 #endif
227 #ifdef CONFIG_HPAPCI
228 	if (hp300_model < HP_400) {
229 		if (!num_ports)
230 			return -ENODEV;
231 		return 0;
232 	}
233 	/* These models have the Frodo chip.
234 	 * Port 0 is reserved for the Apollo Domain keyboard.
235 	 * Port 1 is either the console or the DCA.
236 	 */
237 	for (i = 1; i < 4; i++) {
238 		/* Port 1 is the console on a 425e, on other machines it's
239 		 * mapped to DCA.
240 		 */
241 #ifdef CONFIG_SERIAL_8250_CONSOLE
242 		if (i == 1)
243 			continue;
244 #endif
245 
246 		/* Create new serial device */
247 		port = kmalloc(sizeof(struct hp300_port), GFP_KERNEL);
248 		if (!port)
249 			return -ENOMEM;
250 
251 		memset(&uport, 0, sizeof(struct uart_port));
252 
253 		base = (FRODO_BASE + FRODO_APCI_OFFSET(i));
254 
255 		/* Memory mapped I/O */
256 		uport.iotype = UPIO_MEM;
257 		uport.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ \
258 			      | UPF_BOOT_AUTOCONF;
259 		/* XXX - no interrupt support yet */
260 		uport.irq = 0;
261 		uport.uartclk = HPAPCI_BAUD_BASE * 16;
262 		uport.mapbase = base;
263 		uport.membase = (char *)(base + DIO_VIRADDRBASE);
264 		uport.regshift = 2;
265 
266 		line = serial8250_register_port(&uport);
267 
268 		if (line < 0) {
269 			printk(KERN_NOTICE "8250_hp300: register_serial() APCI"
270 			       " %d irq %d failed\n", i, uport.irq);
271 			kfree(port);
272 			continue;
273 		}
274 
275 		port->line = line;
276 		port->next = hp300_ports;
277 		hp300_ports = port;
278 
279 		num_ports++;
280 	}
281 #endif
282 
283 	/* Any boards found? */
284 	if (!num_ports)
285 		return -ENODEV;
286 
287 	return 0;
288 }
289 
290 #ifdef CONFIG_HPDCA
hpdca_remove_one(struct dio_dev * d)291 static void __devexit hpdca_remove_one(struct dio_dev *d)
292 {
293 	int line;
294 
295 	line = (int) dio_get_drvdata(d);
296 	if (d->resource.start) {
297 		/* Disable board-interrupts */
298 		out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, 0);
299 	}
300 	serial8250_unregister_port(line);
301 }
302 #endif
303 
hp300_8250_exit(void)304 static void __exit hp300_8250_exit(void)
305 {
306 #ifdef CONFIG_HPAPCI
307 	struct hp300_port *port, *to_free;
308 
309 	for (port = hp300_ports; port; ) {
310 		serial8250_unregister_port(port->line);
311 		to_free = port;
312 		port = port->next;
313 		kfree(to_free);
314 	}
315 
316 	hp300_ports = NULL;
317 #endif
318 #ifdef CONFIG_HPDCA
319 	dio_unregister_driver(&hpdca_driver);
320 #endif
321 }
322 
323 module_init(hp300_8250_init);
324 module_exit(hp300_8250_exit);
325 MODULE_DESCRIPTION("HP DCA/APCI serial driver");
326 MODULE_AUTHOR("Kars de Jong <jongk@linux-m68k.org>");
327 MODULE_LICENSE("GPL");
328