1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Driver for the 98626/98644/internal serial interface on hp300/hp400
4 * (based on the National Semiconductor INS8250/NS16550AF/WD16C552 UARTs)
5 *
6 * Ported from 2.2 and modified to use the normal 8250 driver
7 * by Kars de Jong <jongk@linux-m68k.org>, May 2004.
8 */
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/string.h>
12#include <linux/kernel.h>
13#include <linux/serial.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) && !defined(CONFIG_COMPILE_TEST)
24#warning CONFIG_SERIAL_8250 defined but neither CONFIG_HPDCA nor CONFIG_HPAPCI defined, are you sure?
25#endif
26
27#ifdef CONFIG_HPAPCI
28struct hp300_port {
29 struct hp300_port *next; /* next port */
30 int line; /* line (tty) number */
31};
32
33static struct hp300_port *hp300_ports;
34#endif
35
36#ifdef CONFIG_HPDCA
37
38static int hpdca_init_one(struct dio_dev *d,
39 const struct dio_device_id *ent);
40static void hpdca_remove_one(struct dio_dev *d);
41
42static struct dio_device_id hpdca_dio_tbl[] = {
43 { DIO_ID_DCA0 },
44 { DIO_ID_DCA0REM },
45 { DIO_ID_DCA1 },
46 { DIO_ID_DCA1REM },
47 { 0 }
48};
49
50static struct dio_driver hpdca_driver = {
51 .name = "hpdca",
52 .id_table = hpdca_dio_tbl,
53 .probe = hpdca_init_one,
54 .remove = hpdca_remove_one,
55};
56
57#endif
58
59static unsigned int num_ports;
60
61extern int hp300_uart_scode;
62
63/* Offset to UART registers from base of DCA */
64#define UART_OFFSET 17
65
66#define DCA_ID 0x01 /* ID (read), reset (write) */
67#define DCA_IC 0x03 /* Interrupt control */
68
69/* Interrupt control */
70#define DCA_IC_IE 0x80 /* Master interrupt enable */
71
72#define HPDCA_BAUD_BASE 153600
73
74/* Base address of the Frodo part */
75#define FRODO_BASE (0x41c000)
76
77/*
78 * Where we find the 8250-like APCI ports, and how far apart they are.
79 */
80#define FRODO_APCIBASE 0x0
81#define FRODO_APCISPACE 0x20
82#define FRODO_APCI_OFFSET(x) (FRODO_APCIBASE + ((x) * FRODO_APCISPACE))
83
84#define HPAPCI_BAUD_BASE 500400
85
86#ifdef CONFIG_SERIAL_8250_CONSOLE
87/*
88 * Parse the bootinfo to find descriptions for headless console and
89 * debug serial ports and register them with the 8250 driver.
90 */
91int __init hp300_setup_serial_console(void)
92{
93 int scode;
94 struct uart_port port;
95
96 memset(&port, 0, sizeof(port));
97
98 if (hp300_uart_scode < 0 || hp300_uart_scode > DIO_SCMAX)
99 return 0;
100
101 if (DIO_SCINHOLE(hp300_uart_scode))
102 return 0;
103
104 scode = hp300_uart_scode;
105
106 /* Memory mapped I/O */
107 port.iotype = UPIO_MEM;
108 port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
109 port.type = PORT_UNKNOWN;
110
111 /* Check for APCI console */
112 if (scode == 256) {
113#ifdef CONFIG_HPAPCI
114 pr_info("Serial console is HP APCI 1\n");
115
116 port.uartclk = HPAPCI_BAUD_BASE * 16;
117 port.mapbase = (FRODO_BASE + FRODO_APCI_OFFSET(1));
118 port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
119 port.regshift = 2;
120 add_preferred_console("ttyS", port.line, "9600n8");
121#else
122 pr_warn("Serial console is APCI but support is disabled (CONFIG_HPAPCI)!\n");
123 return 0;
124#endif
125 } else {
126#ifdef CONFIG_HPDCA
127 unsigned long pa = dio_scodetophysaddr(scode);
128 if (!pa)
129 return 0;
130
131 pr_info("Serial console is HP DCA at select code %d\n", scode);
132
133 port.uartclk = HPDCA_BAUD_BASE * 16;
134 port.mapbase = (pa + UART_OFFSET);
135 port.membase = (char *)(port.mapbase + DIO_VIRADDRBASE);
136 port.regshift = 1;
137 port.irq = DIO_IPL(pa + DIO_VIRADDRBASE);
138
139 /* Enable board-interrupts */
140 out_8(pa + DIO_VIRADDRBASE + DCA_IC, DCA_IC_IE);
141
142 if (DIO_ID(pa + DIO_VIRADDRBASE) & 0x80)
143 add_preferred_console("ttyS", port.line, "9600n8");
144#else
145 pr_warn("Serial console is DCA but support is disabled (CONFIG_HPDCA)!\n");
146 return 0;
147#endif
148 }
149
150 if (early_serial_setup(port: &port) < 0)
151 pr_warn("%s: early_serial_setup() failed.\n", __func__);
152 return 0;
153}
154#endif /* CONFIG_SERIAL_8250_CONSOLE */
155
156#ifdef CONFIG_HPDCA
157static int hpdca_init_one(struct dio_dev *d,
158 const struct dio_device_id *ent)
159{
160 struct uart_8250_port uart;
161 int line;
162
163#ifdef CONFIG_SERIAL_8250_CONSOLE
164 if (hp300_uart_scode == d->scode) {
165 /* Already got it. */
166 return 0;
167 }
168#endif
169 memset(&uart, 0, sizeof(uart));
170
171 /* Memory mapped I/O */
172 uart.port.iotype = UPIO_MEM;
173 uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF;
174 uart.port.irq = d->ipl;
175 uart.port.uartclk = HPDCA_BAUD_BASE * 16;
176 uart.port.mapbase = (d->resource.start + UART_OFFSET);
177 uart.port.membase = (char *)(uart.port.mapbase + DIO_VIRADDRBASE);
178 uart.port.regshift = 1;
179 uart.port.dev = &d->dev;
180 line = serial8250_register_8250_port(&uart);
181
182 if (line < 0) {
183 dev_notice(&d->dev,
184 "8250_hp300: register_serial() DCA scode %d irq %d failed\n",
185 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
203static 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 dev_notice(uart.port.dev,
266 "8250_hp300: register_serial() APCI %d irq %d failed\n",
267 i, uart.port.irq);
268 kfree(port);
269 continue;
270 }
271
272 port->line = line;
273 port->next = hp300_ports;
274 hp300_ports = port;
275
276 num_ports++;
277 }
278#endif
279
280 /* Any boards found? */
281 if (!num_ports)
282 return -ENODEV;
283
284 return 0;
285}
286
287#ifdef CONFIG_HPDCA
288static void hpdca_remove_one(struct dio_dev *d)
289{
290 int line;
291
292 line = (int) dio_get_drvdata(d);
293 if (d->resource.start) {
294 /* Disable board-interrupts */
295 out_8(d->resource.start + DIO_VIRADDRBASE + DCA_IC, 0);
296 }
297 serial8250_unregister_port(line);
298}
299#endif
300
301static void __exit hp300_8250_exit(void)
302{
303#ifdef CONFIG_HPAPCI
304 struct hp300_port *port, *to_free;
305
306 for (port = hp300_ports; port; ) {
307 serial8250_unregister_port(port->line);
308 to_free = port;
309 port = port->next;
310 kfree(to_free);
311 }
312
313 hp300_ports = NULL;
314#endif
315#ifdef CONFIG_HPDCA
316 dio_unregister_driver(&hpdca_driver);
317#endif
318}
319
320module_init(hp300_8250_init);
321module_exit(hp300_8250_exit);
322MODULE_DESCRIPTION("HP DCA/APCI serial driver");
323MODULE_AUTHOR("Kars de Jong <jongk@linux-m68k.org>");
324MODULE_LICENSE("GPL");
325

source code of linux/drivers/tty/serial/8250/8250_hp300.c