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 .notifier_add = notifier_add_irq, 56 .notifier_del = notifier_del_irq, 57 .notifier_hangup = notifier_hangup_irq, 58 }; 59 60 static int hvc_opal_hvsi_get_chars(uint32_t vtermno, char *buf, int count) 61 { 62 struct hvc_opal_priv *pv = hvc_opal_privs[vtermno]; 63 64 if (WARN_ON(!pv)) 65 return -ENODEV; 66 67 return hvsilib_get_chars(&pv->hvsi, buf, count); 68 } 69 70 static int hvc_opal_hvsi_put_chars(uint32_t vtermno, const char *buf, int count) 71 { 72 struct hvc_opal_priv *pv = hvc_opal_privs[vtermno]; 73 74 if (WARN_ON(!pv)) 75 return -ENODEV; 76 77 return hvsilib_put_chars(&pv->hvsi, buf, count); 78 } 79 80 static int hvc_opal_hvsi_open(struct hvc_struct *hp, int data) 81 { 82 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno]; 83 int rc; 84 85 pr_devel("HVSI@%x: do open !\n", hp->vtermno); 86 87 rc = notifier_add_irq(hp, data); 88 if (rc) 89 return rc; 90 91 return hvsilib_open(&pv->hvsi, hp); 92 } 93 94 static void hvc_opal_hvsi_close(struct hvc_struct *hp, int data) 95 { 96 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno]; 97 98 pr_devel("HVSI@%x: do close !\n", hp->vtermno); 99 100 hvsilib_close(&pv->hvsi, hp); 101 102 notifier_del_irq(hp, data); 103 } 104 105 void hvc_opal_hvsi_hangup(struct hvc_struct *hp, int data) 106 { 107 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno]; 108 109 pr_devel("HVSI@%x: do hangup !\n", hp->vtermno); 110 111 hvsilib_close(&pv->hvsi, hp); 112 113 notifier_hangup_irq(hp, data); 114 } 115 116 static int hvc_opal_hvsi_tiocmget(struct hvc_struct *hp) 117 { 118 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno]; 119 120 if (!pv) 121 return -EINVAL; 122 return pv->hvsi.mctrl; 123 } 124 125 static int hvc_opal_hvsi_tiocmset(struct hvc_struct *hp, unsigned int set, 126 unsigned int clear) 127 { 128 struct hvc_opal_priv *pv = hvc_opal_privs[hp->vtermno]; 129 130 pr_devel("HVSI@%x: Set modem control, set=%x,clr=%x\n", 131 hp->vtermno, set, clear); 132 133 if (set & TIOCM_DTR) 134 hvsilib_write_mctrl(&pv->hvsi, 1); 135 else if (clear & TIOCM_DTR) 136 hvsilib_write_mctrl(&pv->hvsi, 0); 137 138 return 0; 139 } 140 141 static const struct hv_ops hvc_opal_hvsi_ops = { 142 .get_chars = hvc_opal_hvsi_get_chars, 143 .put_chars = hvc_opal_hvsi_put_chars, 144 .notifier_add = hvc_opal_hvsi_open, 145 .notifier_del = hvc_opal_hvsi_close, 146 .notifier_hangup = hvc_opal_hvsi_hangup, 147 .tiocmget = hvc_opal_hvsi_tiocmget, 148 .tiocmset = hvc_opal_hvsi_tiocmset, 149 }; 150 151 static int hvc_opal_probe(struct platform_device *dev) 152 { 153 const struct hv_ops *ops; 154 struct hvc_struct *hp; 155 struct hvc_opal_priv *pv; 156 hv_protocol_t proto; 157 unsigned int termno, irq, boot = 0; 158 const __be32 *reg; 159 160 if (of_device_is_compatible(dev->dev.of_node, "ibm,opal-console-raw")) { 161 proto = HV_PROTOCOL_RAW; 162 ops = &hvc_opal_raw_ops; 163 } else if (of_device_is_compatible(dev->dev.of_node, 164 "ibm,opal-console-hvsi")) { 165 proto = HV_PROTOCOL_HVSI; 166 ops = &hvc_opal_hvsi_ops; 167 } else { 168 pr_err("hvc_opal: Unknown protocol for %pOF\n", 169 dev->dev.of_node); 170 return -ENXIO; 171 } 172 173 reg = of_get_property(dev->dev.of_node, "reg", NULL); 174 termno = reg ? be32_to_cpup(reg) : 0; 175 176 /* Is it our boot one ? */ 177 if (hvc_opal_privs[termno] == &hvc_opal_boot_priv) { 178 pv = hvc_opal_privs[termno]; 179 boot = 1; 180 } else if (hvc_opal_privs[termno] == NULL) { 181 pv = kzalloc(sizeof(struct hvc_opal_priv), GFP_KERNEL); 182 if (!pv) 183 return -ENOMEM; 184 pv->proto = proto; 185 hvc_opal_privs[termno] = pv; 186 if (proto == HV_PROTOCOL_HVSI) 187 hvsilib_init(&pv->hvsi, opal_get_chars, opal_put_chars, 188 termno, 0); 189 190 /* Instanciate now to establish a mapping index==vtermno */ 191 hvc_instantiate(termno, termno, ops); 192 } else { 193 pr_err("hvc_opal: Device %pOF has duplicate terminal number #%d\n", 194 dev->dev.of_node, termno); 195 return -ENXIO; 196 } 197 198 pr_info("hvc%d: %s protocol on %pOF%s\n", termno, 199 proto == HV_PROTOCOL_RAW ? "raw" : "hvsi", 200 dev->dev.of_node, 201 boot ? " (boot console)" : ""); 202 203 irq = irq_of_parse_and_map(dev->dev.of_node, 0); 204 if (!irq) { 205 pr_info("hvc%d: No interrupts property, using OPAL event\n", 206 termno); 207 irq = opal_event_request(ilog2(OPAL_EVENT_CONSOLE_INPUT)); 208 } 209 210 if (!irq) { 211 pr_err("hvc_opal: Unable to map interrupt for device %pOF\n", 212 dev->dev.of_node); 213 return irq; 214 } 215 216 hp = hvc_alloc(termno, irq, ops, MAX_VIO_PUT_CHARS); 217 if (IS_ERR(hp)) 218 return PTR_ERR(hp); 219 220 /* hvc consoles on powernv may need to share a single irq */ 221 hp->flags = IRQF_SHARED; 222 dev_set_drvdata(&dev->dev, hp); 223 224 return 0; 225 } 226 227 static int hvc_opal_remove(struct platform_device *dev) 228 { 229 struct hvc_struct *hp = dev_get_drvdata(&dev->dev); 230 int rc, termno; 231 232 termno = hp->vtermno; 233 rc = hvc_remove(hp); 234 if (rc == 0) { 235 if (hvc_opal_privs[termno] != &hvc_opal_boot_priv) 236 kfree(hvc_opal_privs[termno]); 237 hvc_opal_privs[termno] = NULL; 238 } 239 return rc; 240 } 241 242 static struct platform_driver hvc_opal_driver = { 243 .probe = hvc_opal_probe, 244 .remove = hvc_opal_remove, 245 .driver = { 246 .name = hvc_opal_name, 247 .of_match_table = hvc_opal_match, 248 } 249 }; 250 251 static int __init hvc_opal_init(void) 252 { 253 if (!firmware_has_feature(FW_FEATURE_OPAL)) 254 return -ENODEV; 255 256 /* Register as a vio device to receive callbacks */ 257 return platform_driver_register(&hvc_opal_driver); 258 } 259 device_initcall(hvc_opal_init); 260 261 static void udbg_opal_putc(char c) 262 { 263 unsigned int termno = hvc_opal_boot_termno; 264 int count = -1; 265 266 if (c == '\n') 267 udbg_opal_putc('\r'); 268 269 do { 270 switch(hvc_opal_boot_priv.proto) { 271 case HV_PROTOCOL_RAW: 272 count = opal_put_chars(termno, &c, 1); 273 break; 274 case HV_PROTOCOL_HVSI: 275 count = hvc_opal_hvsi_put_chars(termno, &c, 1); 276 break; 277 } 278 } while(count == 0 || count == -EAGAIN); 279 } 280 281 static int udbg_opal_getc_poll(void) 282 { 283 unsigned int termno = hvc_opal_boot_termno; 284 int rc = 0; 285 char c; 286 287 switch(hvc_opal_boot_priv.proto) { 288 case HV_PROTOCOL_RAW: 289 rc = opal_get_chars(termno, &c, 1); 290 break; 291 case HV_PROTOCOL_HVSI: 292 rc = hvc_opal_hvsi_get_chars(termno, &c, 1); 293 break; 294 } 295 if (!rc) 296 return -1; 297 return c; 298 } 299 300 static int udbg_opal_getc(void) 301 { 302 int ch; 303 for (;;) { 304 ch = udbg_opal_getc_poll(); 305 if (ch == -1) { 306 /* This shouldn't be needed...but... */ 307 volatile unsigned long delay; 308 for (delay=0; delay < 2000000; delay++) 309 ; 310 } else { 311 return ch; 312 } 313 } 314 } 315 316 static void udbg_init_opal_common(void) 317 { 318 udbg_putc = udbg_opal_putc; 319 udbg_getc = udbg_opal_getc; 320 udbg_getc_poll = udbg_opal_getc_poll; 321 } 322 323 void __init hvc_opal_init_early(void) 324 { 325 struct device_node *stdout_node = of_node_get(of_stdout); 326 const __be32 *termno; 327 const struct hv_ops *ops; 328 u32 index; 329 330 /* If the console wasn't in /chosen, try /ibm,opal */ 331 if (!stdout_node) { 332 struct device_node *opal, *np; 333 334 /* Current OPAL takeover doesn't provide the stdout 335 * path, so we hard wire it 336 */ 337 opal = of_find_node_by_path("/ibm,opal/consoles"); 338 if (opal) 339 pr_devel("hvc_opal: Found consoles in new location\n"); 340 if (!opal) { 341 opal = of_find_node_by_path("/ibm,opal"); 342 if (opal) 343 pr_devel("hvc_opal: " 344 "Found consoles in old location\n"); 345 } 346 if (!opal) 347 return; 348 for_each_child_of_node(opal, np) { 349 if (!strcmp(np->name, "serial")) { 350 stdout_node = np; 351 break; 352 } 353 } 354 of_node_put(opal); 355 } 356 if (!stdout_node) 357 return; 358 termno = of_get_property(stdout_node, "reg", NULL); 359 index = termno ? be32_to_cpup(termno) : 0; 360 if (index >= MAX_NR_HVC_CONSOLES) 361 return; 362 hvc_opal_privs[index] = &hvc_opal_boot_priv; 363 364 /* Check the protocol */ 365 if (of_device_is_compatible(stdout_node, "ibm,opal-console-raw")) { 366 hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW; 367 ops = &hvc_opal_raw_ops; 368 pr_devel("hvc_opal: Found RAW console\n"); 369 } 370 else if (of_device_is_compatible(stdout_node,"ibm,opal-console-hvsi")) { 371 hvc_opal_boot_priv.proto = HV_PROTOCOL_HVSI; 372 ops = &hvc_opal_hvsi_ops; 373 hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars, 374 opal_put_chars, index, 1); 375 /* HVSI, perform the handshake now */ 376 hvsilib_establish(&hvc_opal_boot_priv.hvsi); 377 pr_devel("hvc_opal: Found HVSI console\n"); 378 } else 379 goto out; 380 hvc_opal_boot_termno = index; 381 udbg_init_opal_common(); 382 add_preferred_console("hvc", index, NULL); 383 hvc_instantiate(index, index, ops); 384 out: 385 of_node_put(stdout_node); 386 } 387 388 #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW 389 void __init udbg_init_debug_opal_raw(void) 390 { 391 u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO; 392 hvc_opal_privs[index] = &hvc_opal_boot_priv; 393 hvc_opal_boot_priv.proto = HV_PROTOCOL_RAW; 394 hvc_opal_boot_termno = index; 395 udbg_init_opal_common(); 396 } 397 #endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_RAW */ 398 399 #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI 400 void __init udbg_init_debug_opal_hvsi(void) 401 { 402 u32 index = CONFIG_PPC_EARLY_DEBUG_OPAL_VTERMNO; 403 hvc_opal_privs[index] = &hvc_opal_boot_priv; 404 hvc_opal_boot_termno = index; 405 udbg_init_opal_common(); 406 hvsilib_init(&hvc_opal_boot_priv.hvsi, opal_get_chars, opal_put_chars, 407 index, 1); 408 hvsilib_establish(&hvc_opal_boot_priv.hvsi); 409 } 410 #endif /* CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI */ 411