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 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 71 static 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 82 static 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 96 static 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 } 106 107 static 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 } 117 118 static 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 } 126 127 static 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 } 142 143 static 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 }; 153 154 static 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(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(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(dev->dev.of_node, "reg", NULL); 177 termno = reg ? be32_to_cpup(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(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(termno, 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(dev->dev.of_node, 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(termno, irq, ops, MAX_VIO_PUT_CHARS); 226 if (IS_ERR(hp)) 227 return PTR_ERR(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, hp); 232 233 return 0; 234 } 235 236 static void hvc_opal_remove(struct platform_device *dev) 237 { 238 struct hvc_struct *hp = dev_get_drvdata(&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(hvc_opal_privs[termno]); 245 hvc_opal_privs[termno] = NULL; 246 } 247 248 static 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 }; 256 257 static 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 } 265 device_initcall(hvc_opal_init); 266 267 static 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('\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(termno, &c, 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 } 291 292 static 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(termno, &c, 1); 304 break; 305 } 306 if (!rc) 307 return -1; 308 return c; 309 } 310 311 static 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 } 320 321 static 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 } 327 328 void __init hvc_opal_init_early(void) 329 { 330 struct device_node *stdout_node = of_node_get(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("/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("/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, "serial")) { 355 stdout_node = np; 356 break; 357 } 358 } 359 of_node_put(opal); 360 } 361 if (!stdout_node) 362 return; 363 termno = of_get_property(stdout_node, "reg", NULL); 364 index = termno ? be32_to_cpup(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(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(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("hvc", index, NULL); 389 hvc_instantiate(index, index, ops); 390 out: 391 of_node_put(stdout_node); 392 } 393 394 #ifdef CONFIG_PPC_EARLY_DEBUG_OPAL_RAW 395 void __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 406 void __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