1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * opal driver interface to hvc_console.c
4 *
5 * Copyright 2011 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
6 */
7
8 #undef DEBUG
9
10 #include <linux/types.h>
11 #include <linux/init.h>
12 #include <linux/delay.h>
13 #include <linux/slab.h>
14 #include <linux/console.h>
15 #include <linux/of.h>
16 #include <linux/of_platform.h>
17 #include <linux/export.h>
18 #include <linux/interrupt.h>
19
20 #include <asm/hvconsole.h>
21 #include <asm/prom.h>
22 #include <asm/firmware.h>
23 #include <asm/hvsi.h>
24 #include <asm/udbg.h>
25 #include <asm/opal.h>
26
27 #include "hvc_console.h"
28
29 static const char hvc_opal_name[] = "hvc_opal";
30
31 static const struct of_device_id hvc_opal_match[] = {
32 { .name = "serial", .compatible = "ibm,opal-console-raw" },
33 { .name = "serial", .compatible = "ibm,opal-console-hvsi" },
34 { },
35 };
36
37 typedef enum hv_protocol {
38 HV_PROTOCOL_RAW,
39 HV_PROTOCOL_HVSI
40 } hv_protocol_t;
41
42 struct hvc_opal_priv {
43 hv_protocol_t proto; /* Raw data or HVSI packets */
44 struct hvsi_priv hvsi; /* HVSI specific data */
45 };
46 static struct hvc_opal_priv *hvc_opal_privs[MAX_NR_HVC_CONSOLES];
47
48 /* For early boot console */
49 static struct hvc_opal_priv hvc_opal_boot_priv;
50 static u32 hvc_opal_boot_termno;
51
52 static const struct hv_ops hvc_opal_raw_ops = {
53 .get_chars = opal_get_chars,
54 .put_chars = opal_put_chars,
55 .flush = opal_flush_chars,
56 .notifier_add = notifier_add_irq,
57 .notifier_del = notifier_del_irq,
58 .notifier_hangup = notifier_hangup_irq,
59 };
60
hvc_opal_hvsi_get_chars(uint32_t vtermno,char * buf,int count)61 static int hvc_opal_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
62 {
63 struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
64
65 if (WARN_ON(!pv))
66 return -ENODEV;
67
68 return hvsilib_get_chars(&pv->hvsi, buf, count);
69 }
70
hvc_opal_hvsi_put_chars(uint32_t vtermno,const char * buf,int count)71 static int hvc_opal_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
72 {
73 struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
74
75 if (WARN_ON(!pv))
76 return -ENODEV;
77
78 return hvsilib_put_chars(&pv->hvsi, buf, count);
79 }
80
hvc_opal_hvsi_open(struct hvc_struct * hp,int data)81 static int hvc_opal_hvsi_open(struct hvc_struct *hp, int data)
82 {
83 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
84 int rc;
85
86 pr_devel("HVSI@%x: do open !\n", hp->vtermno);
87
88 rc = notifier_add_irq(hp, data);
89 if (rc)
90 return rc;
91
92 return hvsilib_open(&pv->hvsi, hp);
93 }
94
hvc_opal_hvsi_close(struct hvc_struct * hp,int data)95 static void hvc_opal_hvsi_close(struct hvc_struct *hp, int data)
96 {
97 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
98
99 pr_devel("HVSI@%x: do close !\n", hp->vtermno);
100
101 hvsilib_close(&pv->hvsi, hp);
102
103 notifier_del_irq(hp, data);
104 }
105
hvc_opal_hvsi_hangup(struct hvc_struct * hp,int data)106 void hvc_opal_hvsi_hangup(struct hvc_struct *hp, int data)
107 {
108 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
109
110 pr_devel("HVSI@%x: do hangup !\n", hp->vtermno);
111
112 hvsilib_close(&pv->hvsi, hp);
113
114 notifier_hangup_irq(hp, data);
115 }
116
hvc_opal_hvsi_tiocmget(struct hvc_struct * hp)117 static int hvc_opal_hvsi_tiocmget(struct hvc_struct *hp)
118 {
119 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
120
121 if (!pv)
122 return -EINVAL;
123 return pv->hvsi.mctrl;
124 }
125
hvc_opal_hvsi_tiocmset(struct hvc_struct * hp,unsigned int set,unsigned int clear)126 static int hvc_opal_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
127 unsigned int clear)
128 {
129 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
130
131 pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
132 hp->vtermno, set, clear);
133
134 if (set & TIOCM_DTR)
135 hvsilib_write_mctrl(&pv->hvsi, 1);
136 else if (clear & TIOCM_DTR)
137 hvsilib_write_mctrl(&pv->hvsi, 0);
138
139 return 0;
140 }
141
142 static const struct hv_ops hvc_opal_hvsi_ops = {
143 .get_chars = hvc_opal_hvsi_get_chars,
144 .put_chars = hvc_opal_hvsi_put_chars,
145 .flush = opal_flush_chars,
146 .notifier_add = hvc_opal_hvsi_open,
147 .notifier_del = hvc_opal_hvsi_close,
148 .notifier_hangup = hvc_opal_hvsi_hangup,
149 .tiocmget = hvc_opal_hvsi_tiocmget,
150 .tiocmset = hvc_opal_hvsi_tiocmset,
151 };
152
hvc_opal_probe(struct platform_device * dev)153 static int hvc_opal_probe(struct platform_device *dev)
154 {
155 const struct hv_ops *ops;
156 struct hvc_struct *hp;
157 struct hvc_opal_priv *pv;
158 hv_protocol_t proto;
159 unsigned int termno, irq, boot = 0;
160 const __be32 *reg;
161
162 if (of_device_is_compatible(dev->dev.of_node, "ibm,opal-console-raw")) {
163 proto = HV_PROTOCOL_RAW;
164 ops = &hvc_opal_raw_ops;
165 } else if (of_device_is_compatible(dev->dev.of_node,
166 "ibm,opal-console-hvsi")) {
167 proto = HV_PROTOCOL_HVSI;
168 ops = &hvc_opal_hvsi_ops;
169 } else {
170 pr_err("hvc_opal: Unknown protocol for %pOF\n",
171 dev->dev.of_node);
172 return -ENXIO;
173 }
174
175 reg = of_get_property(dev->dev.of_node, "reg", NULL);
176 termno = reg ? be32_to_cpup(reg) : 0;
177
178 /* Is it our boot one ? */
179 if (hvc_opal_privs[termno] == &hvc_opal_boot_priv) {
180 pv = hvc_opal_privs[termno];
181 boot = 1;
182 } else if (hvc_opal_privs[termno] == NULL) {
183 pv = kzalloc(sizeof(struct hvc_opal_priv), GFP_KERNEL);
184 if (!pv)
185 return -ENOMEM;
186 pv->proto = proto;
187 hvc_opal_privs[termno] = pv;
188 if (proto == HV_PROTOCOL_HVSI) {
189 /*
190 * We want put_chars to be atomic to avoid mangling of
191 * hvsi packets.
192 */
193 hvsilib_init(&pv->hvsi,
194 opal_get_chars, opal_put_chars_atomic,
195 termno, 0);
196 }
197
198 /* Instanciate now to establish a mapping index==vtermno */
199 hvc_instantiate(termno, termno, ops);
200 } else {
201 pr_err("hvc_opal: Device %pOF has duplicate terminal number #%d\n",
202 dev->dev.of_node, termno);
203 return -ENXIO;
204 }
205
206 pr_info("hvc%d: %s protocol on %pOF%s\n", termno,
207 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi",
208 dev->dev.of_node,
209 boot ? " (boot console)" : "");
210
211 irq = irq_of_parse_and_map(dev->dev.of_node, 0);
212 if (!irq) {
213 pr_info("hvc%d: No interrupts property, using OPAL event\n",
214 termno);
215 irq = opal_event_request(ilog2(OPAL_EVENT_CONSOLE_INPUT));
216 }
217
218 if (!irq) {
219 pr_err("hvc_opal: Unable to map interrupt for device %pOF\n",
220 dev->dev.of_node);
221 return irq;
222 }
223
224 hp = hvc_alloc(termno, irq, ops, MAX_VIO_PUT_CHARS);
225 if (IS_ERR(hp))
226 return PTR_ERR(hp);
227
228 /* hvc consoles on powernv may need to share a single irq */
229 hp->flags = IRQF_SHARED;
230 dev_set_drvdata(&dev->dev, hp);
231
232 return 0;
233 }
234
hvc_opal_remove(struct platform_device * dev)235 static int hvc_opal_remove(struct platform_device *dev)
236 {
237 struct hvc_struct *hp = dev_get_drvdata(&dev->dev);
238 int rc, termno;
239
240 termno = hp->vtermno;
241 rc = hvc_remove(hp);
242 if (rc == 0) {
243 if (hvc_opal_privs[termno] != &hvc_opal_boot_priv)
244 kfree(hvc_opal_privs[termno]);
245 hvc_opal_privs[termno] = NULL;
246 }
247 return rc;
248 }
249
250 static struct platform_driver hvc_opal_driver = {
251 .probe = hvc_opal_probe,
252 .remove = hvc_opal_remove,
253 .driver = {
254 .name = hvc_opal_name,
255 .of_match_table = hvc_opal_match,
256 }
257 };
258
hvc_opal_init(void)259 static int __init hvc_opal_init(void)
260 {
261 if (!firmware_has_feature(FW_FEATURE_OPAL))
262 return -ENODEV;
263
264 /* Register as a vio device to receive callbacks */
265 return platform_driver_register(&hvc_opal_driver);
266 }
267 device_initcall(hvc_opal_init);
268
udbg_opal_putc(char c)269 static void udbg_opal_putc(char c)
270 {
271 unsigned int termno = hvc_opal_boot_termno;
272 int count = -1;
273
274 if (c == '\n')
275 udbg_opal_putc('\r');
276
277 do {
278 switch(hvc_opal_boot_priv.proto) {
279 case HV_PROTOCOL_RAW:
280 count = opal_put_chars(termno, &c, 1);
281 break;
282 case HV_PROTOCOL_HVSI:
283 count = hvc_opal_hvsi_put_chars(termno, &c, 1);
284 break;
285 }
286
287 /* This is needed for the cosole to flush
288 * when there aren't any interrupts.
289 */
290 opal_flush_console(termno);
291 } while(count == 0 || count == -EAGAIN);
292 }
293
udbg_opal_getc_poll(void)294 static int udbg_opal_getc_poll(void)
295 {
296 unsigned int termno = hvc_opal_boot_termno;
297 int rc = 0;
298 char c;
299
300 switch(hvc_opal_boot_priv.proto) {
301 case HV_PROTOCOL_RAW:
302 rc = opal_get_chars(termno, &c, 1);
303 break;
304 case HV_PROTOCOL_HVSI:
305 rc = hvc_opal_hvsi_get_chars(termno, &c, 1);
306 break;
307 }
308 if (!rc)
309 return -1;
310 return c;
311 }
312
udbg_opal_getc(void)313 static int udbg_opal_getc(void)
314 {
315 int ch;
316 for (;;) {
317 ch = udbg_opal_getc_poll();
318 if (ch != -1)
319 return ch;
320 }
321 }
322
udbg_init_opal_common(void)323 static void udbg_init_opal_common(void)
324 {
325 udbg_putc = udbg_opal_putc;
326 udbg_getc = udbg_opal_getc;
327 udbg_getc_poll = udbg_opal_getc_poll;
328 }
329
hvc_opal_init_early(void)330 void __init hvc_opal_init_early(void)
331 {
332 struct device_node *stdout_node = of_node_get(of_stdout);
333 const __be32 *termno;
334 const struct hv_ops *ops;
335 u32 index;
336
337 /* If the console wasn't in /chosen, try /ibm,opal */
338 if (!stdout_node) {
339 struct device_node *opal, *np;
340
341 /* Current OPAL takeover doesn't provide the stdout
342 * path, so we hard wire it
343 */
344 opal = of_find_node_by_path("/ibm,opal/consoles");
345 if (opal)
346 pr_devel("hvc_opal: Found consoles in new location\n");
347 if (!opal) {
348 opal = of_find_node_by_path("/ibm,opal");
349 if (opal)
350 pr_devel("hvc_opal: "
351 "Found consoles in old location\n");
352 }
353 if (!opal)
354 return;
355 for_each_child_of_node(opal, np) {
356 if (!strcmp(np->name, "serial")) {
357 stdout_node = np;
358 break;
359 }
360 }
361 of_node_put(opal);
362 }
363 if (!stdout_node)
364 return;
365 termno = of_get_property(stdout_node, "reg", NULL);
366 index = termno ? be32_to_cpup(termno) : 0;
367 if (index >= MAX_NR_HVC_CONSOLES)
368 return;
369 hvc_opal_privs[index] = &hvc_opal_boot_priv;
370
371 /* Check the protocol */
372 if (of_device_is_compatible(stdout_node, "ibm,opal-console-raw")) {
373 hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
374 ops = &hvc_opal_raw_ops;
375 pr_devel("hvc_opal: Found RAW console\n");
376 }
377 else if (of_device_is_compatible(stdout_node,"ibm,opal-console-hvsi")) {
378 hvc_opal_boot_priv.proto = HV_PROTOCOL_HVSI;
379 ops = &hvc_opal_hvsi_ops;
380 hvsilib_init(&hvc_opal_boot_priv.hvsi,
381 opal_get_chars, opal_put_chars_atomic,
382 index, 1);
383 /* HVSI, perform the handshake now */
384 hvsilib_establish(&hvc_opal_boot_priv.hvsi);
385 pr_devel("hvc_opal: Found HVSI console\n");
386 } else
387 goto out;
388 hvc_opal_boot_termno = index;
389 udbg_init_opal_common();
390 add_preferred_console("hvc", index, NULL);
391 hvc_instantiate(index, index, ops);
392 out:
393 of_node_put(stdout_node);
394 }
395
396 #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW
udbg_init_debug_opal_raw(void)397 void __init udbg_init_debug_opal_raw(void)
398 {
399 u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
400 hvc_opal_privs[index] = &hvc_opal_boot_priv;
401 hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
402 hvc_opal_boot_termno = index;
403 udbg_init_opal_common();
404 }
405 #endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_RAW */
406
407 #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI
udbg_init_debug_opal_hvsi(void)408 void __init udbg_init_debug_opal_hvsi(void)
409 {
410 u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
411 hvc_opal_privs[index] = &hvc_opal_boot_priv;
412 hvc_opal_boot_termno = index;
413 udbg_init_opal_common();
414 hvsilib_init(&hvc_opal_boot_priv.hvsi,
415 opal_get_chars, opal_put_chars_atomic,
416 index, 1);
417 hvsilib_establish(&hvc_opal_boot_priv.hvsi);
418 }
419 #endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI */
420
