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_irq.h>
17#include <linux/platform_device.h>
18#include <linux/export.h>
19#include <linux/interrupt.h>
20
21#include <asm/hvconsole.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
29static const char hvc_opal_name[] = "hvc_opal";
30
31static 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
37typedef enum hv_protocol {
38 HV_PROTOCOL_RAW,
39 HV_PROTOCOL_HVSI
40} hv_protocol_t;
41
42struct hvc_opal_priv {
43 hv_protocol_t proto; /* Raw data or HVSI packets */
44 struct hvsi_priv hvsi; /* HVSI specific data */
45};
46static struct hvc_opal_priv *hvc_opal_privs[MAX_NR_HVC_CONSOLES];
47
48/* For early boot console */
49static struct hvc_opal_priv hvc_opal_boot_priv;
50static u32 hvc_opal_boot_termno;
51
52static 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
61static ssize_t hvc_opal_hvsi_get_chars(uint32_t vtermno, u8 *buf, size_t 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
71static ssize_t hvc_opal_hvsi_put_chars(uint32_t vtermno, const u8 *buf,
72 size_t count)
73{
74 struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
75
76 if (WARN_ON(!pv))
77 return -ENODEV;
78
79 return hvsilib_put_chars(&pv->hvsi, buf, count);
80}
81
82static int hvc_opal_hvsi_open(struct hvc_struct *hp, int data)
83{
84 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
85 int rc;
86
87 pr_devel("HVSI@%x: do open !\n", hp->vtermno);
88
89 rc = notifier_add_irq(hp, data);
90 if (rc)
91 return rc;
92
93 return hvsilib_open(&pv->hvsi, hp);
94}
95
96static void hvc_opal_hvsi_close(struct hvc_struct *hp, int data)
97{
98 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
99
100 pr_devel("HVSI@%x: do close !\n", hp->vtermno);
101
102 hvsilib_close(&pv->hvsi, hp);
103
104 notifier_del_irq(hp, data);
105}
106
107static void hvc_opal_hvsi_hangup(struct hvc_struct *hp, int data)
108{
109 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
110
111 pr_devel("HVSI@%x: do hangup !\n", hp->vtermno);
112
113 hvsilib_close(&pv->hvsi, hp);
114
115 notifier_hangup_irq(hp, data);
116}
117
118static int hvc_opal_hvsi_tiocmget(struct hvc_struct *hp)
119{
120 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
121
122 if (!pv)
123 return -EINVAL;
124 return pv->hvsi.mctrl;
125}
126
127static int hvc_opal_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set,
128 unsigned int clear)
129{
130 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno];
131
132 pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n",
133 hp->vtermno, set, clear);
134
135 if (set & TIOCM_DTR)
136 hvsilib_write_mctrl(&pv->hvsi, 1);
137 else if (clear & TIOCM_DTR)
138 hvsilib_write_mctrl(&pv->hvsi, 0);
139
140 return 0;
141}
142
143static const struct hv_ops hvc_opal_hvsi_ops = {
144 .get_chars = hvc_opal_hvsi_get_chars,
145 .put_chars = hvc_opal_hvsi_put_chars,
146 .flush = opal_flush_chars,
147 .notifier_add = hvc_opal_hvsi_open,
148 .notifier_del = hvc_opal_hvsi_close,
149 .notifier_hangup = hvc_opal_hvsi_hangup,
150 .tiocmget = hvc_opal_hvsi_tiocmget,
151 .tiocmset = hvc_opal_hvsi_tiocmset,
152};
153
154static int hvc_opal_probe(struct platform_device *dev)
155{
156 const struct hv_ops *ops;
157 struct hvc_struct *hp;
158 struct hvc_opal_priv *pv;
159 hv_protocol_t proto;
160 unsigned int termno, irq, boot = 0;
161 const __be32 *reg;
162
163 if (of_device_is_compatible(device: dev->dev.of_node, "ibm,opal-console-raw")) {
164 proto = HV_PROTOCOL_RAW;
165 ops = &hvc_opal_raw_ops;
166 } else if (of_device_is_compatible(device: dev->dev.of_node,
167 "ibm,opal-console-hvsi")) {
168 proto = HV_PROTOCOL_HVSI;
169 ops = &hvc_opal_hvsi_ops;
170 } else {
171 pr_err("hvc_opal: Unknown protocol for %pOF\n",
172 dev->dev.of_node);
173 return -ENXIO;
174 }
175
176 reg = of_get_property(node: dev->dev.of_node, name: "reg", NULL);
177 termno = reg ? be32_to_cpup(p: reg) : 0;
178
179 /* Is it our boot one ? */
180 if (hvc_opal_privs[termno] == &hvc_opal_boot_priv) {
181 pv = hvc_opal_privs[termno];
182 boot = 1;
183 } else if (hvc_opal_privs[termno] == NULL) {
184 pv = kzalloc(size: sizeof(struct hvc_opal_priv), GFP_KERNEL);
185 if (!pv)
186 return -ENOMEM;
187 pv->proto = proto;
188 hvc_opal_privs[termno] = pv;
189 if (proto == HV_PROTOCOL_HVSI) {
190 /*
191 * We want put_chars to be atomic to avoid mangling of
192 * hvsi packets.
193 */
194 hvsilib_init(&pv->hvsi,
195 opal_get_chars, opal_put_chars_atomic,
196 termno, 0);
197 }
198
199 /* Instanciate now to establish a mapping index==vtermno */
200 hvc_instantiate(vtermno: termno, index: termno, ops);
201 } else {
202 pr_err("hvc_opal: Device %pOF has duplicate terminal number #%d\n",
203 dev->dev.of_node, termno);
204 return -ENXIO;
205 }
206
207 pr_info("hvc%d: %s protocol on %pOF%s\n", termno,
208 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi",
209 dev->dev.of_node,
210 boot ? " (boot console)" : "");
211
212 irq = irq_of_parse_and_map(node: dev->dev.of_node, index: 0);
213 if (!irq) {
214 pr_info("hvc%d: No interrupts property, using OPAL event\n",
215 termno);
216 irq = opal_event_request(ilog2(OPAL_EVENT_CONSOLE_INPUT));
217 }
218
219 if (!irq) {
220 pr_err("hvc_opal: Unable to map interrupt for device %pOF\n",
221 dev->dev.of_node);
222 return irq;
223 }
224
225 hp = hvc_alloc(vtermno: termno, data: irq, ops, outbuf_size: MAX_VIO_PUT_CHARS);
226 if (IS_ERR(ptr: hp))
227 return PTR_ERR(ptr: hp);
228
229 /* hvc consoles on powernv may need to share a single irq */
230 hp->flags = IRQF_SHARED;
231 dev_set_drvdata(dev: &dev->dev, data: hp);
232
233 return 0;
234}
235
236static void hvc_opal_remove(struct platform_device *dev)
237{
238 struct hvc_struct *hp = dev_get_drvdata(dev: &dev->dev);
239 int termno;
240
241 termno = hp->vtermno;
242 hvc_remove(hp);
243 if (hvc_opal_privs[termno] != &hvc_opal_boot_priv)
244 kfree(objp: hvc_opal_privs[termno]);
245 hvc_opal_privs[termno] = NULL;
246}
247
248static struct platform_driver hvc_opal_driver = {
249 .probe = hvc_opal_probe,
250 .remove_new = hvc_opal_remove,
251 .driver = {
252 .name = hvc_opal_name,
253 .of_match_table = hvc_opal_match,
254 }
255};
256
257static int __init hvc_opal_init(void)
258{
259 if (!firmware_has_feature(FW_FEATURE_OPAL))
260 return -ENODEV;
261
262 /* Register as a vio device to receive callbacks */
263 return platform_driver_register(&hvc_opal_driver);
264}
265device_initcall(hvc_opal_init);
266
267static void udbg_opal_putc(char c)
268{
269 unsigned int termno = hvc_opal_boot_termno;
270 int count = -1;
271
272 if (c == '\n')
273 udbg_opal_putc(c: '\r');
274
275 do {
276 switch(hvc_opal_boot_priv.proto) {
277 case HV_PROTOCOL_RAW:
278 count = opal_put_chars(termno, &c, 1);
279 break;
280 case HV_PROTOCOL_HVSI:
281 count = hvc_opal_hvsi_put_chars(vtermno: termno, buf: &c, count: 1);
282 break;
283 }
284
285 /* This is needed for the cosole to flush
286 * when there aren't any interrupts.
287 */
288 opal_flush_console(termno);
289 } while(count == 0 || count == -EAGAIN);
290}
291
292static int udbg_opal_getc_poll(void)
293{
294 unsigned int termno = hvc_opal_boot_termno;
295 int rc = 0;
296 char c;
297
298 switch(hvc_opal_boot_priv.proto) {
299 case HV_PROTOCOL_RAW:
300 rc = opal_get_chars(termno, &c, 1);
301 break;
302 case HV_PROTOCOL_HVSI:
303 rc = hvc_opal_hvsi_get_chars(vtermno: termno, buf: &c, count: 1);
304 break;
305 }
306 if (!rc)
307 return -1;
308 return c;
309}
310
311static int udbg_opal_getc(void)
312{
313 int ch;
314 for (;;) {
315 ch = udbg_opal_getc_poll();
316 if (ch != -1)
317 return ch;
318 }
319}
320
321static void udbg_init_opal_common(void)
322{
323 udbg_putc = udbg_opal_putc;
324 udbg_getc = udbg_opal_getc;
325 udbg_getc_poll = udbg_opal_getc_poll;
326}
327
328void __init hvc_opal_init_early(void)
329{
330 struct device_node *stdout_node = of_node_get(node: of_stdout);
331 const __be32 *termno;
332 const struct hv_ops *ops;
333 u32 index;
334
335 /* If the console wasn't in /chosen, try /ibm,opal */
336 if (!stdout_node) {
337 struct device_node *opal, *np;
338
339 /* Current OPAL takeover doesn't provide the stdout
340 * path, so we hard wire it
341 */
342 opal = of_find_node_by_path(path: "/ibm,opal/consoles");
343 if (opal) {
344 pr_devel("hvc_opal: Found consoles in new location\n");
345 } else {
346 opal = of_find_node_by_path(path: "/ibm,opal");
347 if (opal)
348 pr_devel("hvc_opal: "
349 "Found consoles in old location\n");
350 }
351 if (!opal)
352 return;
353 for_each_child_of_node(opal, np) {
354 if (of_node_name_eq(np, name: "serial")) {
355 stdout_node = np;
356 break;
357 }
358 }
359 of_node_put(node: opal);
360 }
361 if (!stdout_node)
362 return;
363 termno = of_get_property(node: stdout_node, name: "reg", NULL);
364 index = termno ? be32_to_cpup(p: termno) : 0;
365 if (index >= MAX_NR_HVC_CONSOLES)
366 return;
367 hvc_opal_privs[index] = &hvc_opal_boot_priv;
368
369 /* Check the protocol */
370 if (of_device_is_compatible(device: stdout_node, "ibm,opal-console-raw")) {
371 hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
372 ops = &hvc_opal_raw_ops;
373 pr_devel("hvc_opal: Found RAW console\n");
374 }
375 else if (of_device_is_compatible(device: stdout_node,"ibm,opal-console-hvsi")) {
376 hvc_opal_boot_priv.proto = HV_PROTOCOL_HVSI;
377 ops = &hvc_opal_hvsi_ops;
378 hvsilib_init(&hvc_opal_boot_priv.hvsi,
379 opal_get_chars, opal_put_chars_atomic,
380 index, 1);
381 /* HVSI, perform the handshake now */
382 hvsilib_establish(&hvc_opal_boot_priv.hvsi);
383 pr_devel("hvc_opal: Found HVSI console\n");
384 } else
385 goto out;
386 hvc_opal_boot_termno = index;
387 udbg_init_opal_common();
388 add_preferred_console(name: "hvc", idx: index, NULL);
389 hvc_instantiate(vtermno: index, index, ops);
390out:
391 of_node_put(node: stdout_node);
392}
393
394#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW
395void __init udbg_init_debug_opal_raw(void)
396{
397 u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
398 hvc_opal_privs[index] = &hvc_opal_boot_priv;
399 hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW;
400 hvc_opal_boot_termno = index;
401 udbg_init_opal_common();
402}
403#endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_RAW */
404
405#ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI
406void __init udbg_init_debug_opal_hvsi(void)
407{
408 u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO;
409 hvc_opal_privs[index] = &hvc_opal_boot_priv;
410 hvc_opal_boot_termno = index;
411 udbg_init_opal_common();
412 hvsilib_init(&hvc_opal_boot_priv.hvsi,
413 opal_get_chars, opal_put_chars_atomic,
414 index, 1);
415 hvsilib_establish(&hvc_opal_boot_priv.hvsi);
416}
417#endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI */
418

source code of linux/drivers/tty/hvc/hvc_opal.c