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 | |
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 | |
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 | |
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 | |
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 | |
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 | |
106 | static 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 | |
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 | |
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 | |
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(device: 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(device: 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(node: dev->dev.of_node, name: "reg" , NULL); |
176 | termno = reg ? be32_to_cpup(p: 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(size: 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(vtermno: termno, index: 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(node: dev->dev.of_node, index: 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(vtermno: termno, data: irq, ops, outbuf_size: MAX_VIO_PUT_CHARS); |
225 | if (IS_ERR(ptr: hp)) |
226 | return PTR_ERR(ptr: 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->dev, data: hp); |
231 | |
232 | return 0; |
233 | } |
234 | |
235 | static int hvc_opal_remove(struct platform_device *dev) |
236 | { |
237 | struct hvc_struct *hp = dev_get_drvdata(dev: &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(objp: 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 | |
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 | |
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(c: '\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(vtermno: termno, buf: &c, count: 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 | |
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(vtermno: termno, buf: &c, count: 1); |
306 | break; |
307 | } |
308 | if (!rc) |
309 | return -1; |
310 | return c; |
311 | } |
312 | |
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 | |
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 | |
330 | void __init hvc_opal_init_early(void) |
331 | { |
332 | struct device_node *stdout_node = of_node_get(node: 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(path: "/ibm,opal/consoles" ); |
345 | if (opal) { |
346 | pr_devel("hvc_opal: Found consoles in new location\n" ); |
347 | } else { |
348 | opal = of_find_node_by_path(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 (of_node_name_eq(np, name: "serial" )) { |
357 | stdout_node = np; |
358 | break; |
359 | } |
360 | } |
361 | of_node_put(node: opal); |
362 | } |
363 | if (!stdout_node) |
364 | return; |
365 | termno = of_get_property(node: stdout_node, name: "reg" , NULL); |
366 | index = termno ? be32_to_cpup(p: 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(device: 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(device: 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(name: "hvc" , idx: index, NULL); |
391 | hvc_instantiate(vtermno: index, index, ops); |
392 | out: |
393 | of_node_put(node: stdout_node); |
394 | } |
395 | |
396 | #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW |
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 |
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 | |